WO2023097469A1 - 电池单体及其制造方法和制造系统、电池以及用电装置 - Google Patents

电池单体及其制造方法和制造系统、电池以及用电装置 Download PDF

Info

Publication number
WO2023097469A1
WO2023097469A1 PCT/CN2021/134485 CN2021134485W WO2023097469A1 WO 2023097469 A1 WO2023097469 A1 WO 2023097469A1 CN 2021134485 W CN2021134485 W CN 2021134485W WO 2023097469 A1 WO2023097469 A1 WO 2023097469A1
Authority
WO
WIPO (PCT)
Prior art keywords
battery cell
electrode assembly
main body
recess
internal pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2021/134485
Other languages
English (en)
French (fr)
Inventor
周文林
李全坤
王鹏
金海族
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Contemporary Amperex Technology Co Ltd
Original Assignee
Contemporary Amperex Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Contemporary Amperex Technology Co Ltd filed Critical Contemporary Amperex Technology Co Ltd
Priority to CN202180089712.3A priority Critical patent/CN116711142A/zh
Priority to EP21965910.9A priority patent/EP4432444A4/en
Priority to PCT/CN2021/134485 priority patent/WO2023097469A1/zh
Publication of WO2023097469A1 publication Critical patent/WO2023097469A1/zh
Priority to US18/669,179 priority patent/US20240313338A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/103—Primary casings; Jackets or wrappings characterised by their shape or physical structure prismatic or rectangular
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/04—Construction or manufacture in general
    • H01M10/0404—Machines for assembling batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/131—Primary casings; Jackets or wrappings characterised by physical properties, e.g. gas permeability, size or heat resistance
    • H01M50/133—Thickness
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/30—Arrangements for facilitating escape of gases
    • H01M50/342—Non-re-sealable arrangements
    • H01M50/3425—Non-re-sealable arrangements in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present application relates to the field of battery technology, and more specifically, to a battery cell, a manufacturing method and system thereof, a battery, and an electrical device.
  • Battery cells are widely used in electronic equipment, such as mobile phones, laptop computers, battery cars, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.
  • the battery cells may include nickel-cadmium battery cells, nickel-hydrogen battery cells, lithium-ion battery cells, secondary alkaline zinc-manganese battery cells, and the like.
  • the present application provides a battery cell, a manufacturing method and a manufacturing system thereof, a battery and an electrical device, which can improve the safety of the battery cell.
  • an embodiment of the present application provides a battery cell, including a case and an electrode assembly accommodated in the case.
  • the shell includes a wall portion, the wall portion includes a main body portion, a connecting portion and a reinforcing portion, the connecting portion surrounds the outer side of the reinforcing portion, and the main body portion surrounds the outer side of the connecting portion.
  • the connecting portion is provided with a weakened area, and the battery cell is configured to rupture along the weakened area to release the internal pressure when the internal pressure of the battery cell reaches a threshold value.
  • the maximum thickness of the reinforcing part is greater than that of the main body, so as to reduce the deformation of the reinforcing part under the action of internal pressure.
  • the walls are deformed by the internal pressure.
  • the main body portion has a smaller thickness than the reinforcing portion, so under the action of internal pressure, the main body portion is more likely to be deformed relative to the reinforcing portion.
  • the stress is transmitted to the connection part, and because the thickness of the reinforcement part is large and not easily deformed, it is difficult for the reinforcement part to release the stress on the connection part through deformation. In this way, the weak area must bear the stress and the internal pressure at the same time role, it is more likely to break.
  • the above scheme can increase the thickness of the weak area without changing the internal pressure required for the weak area to rupture, thereby reducing the risk of the weak area rupture during normal use and prolonging the battery life.
  • the service life of the battery cell is improved, and the safety of the battery cell is improved.
  • the wall portion includes a first recess, and the first recess is recessed from a side of the wall portion away from the electrode assembly in a direction facing the electrode assembly.
  • the reinforcing part includes a first protrusion protruding from the bottom surface of the first recess, and at least part of the first protrusion is accommodated in the first recess.
  • the connecting portion is formed in a region corresponding to the bottom surface of the first concave portion.
  • the above solution reduces the thickness of the connecting portion by opening the first recess on the wall portion, thereby reducing the strength of the weakened area, so that the weakened area can rupture when the internal pressure of the battery cell reaches a threshold.
  • the first protrusion is entirely contained within the first recess.
  • the first concave part can completely accommodate the first convex part, which can prevent the first convex part from increasing the maximum dimension of the shell in the thickness direction and improve the energy density of the battery cell.
  • the reinforcing part protrudes from the surface of the main body facing the electrode assembly.
  • the above solution makes the reinforcing part protrude toward the electrode assembly, so as to increase the thickness and strength of the reinforcing part.
  • the wall portion further includes a second concave portion, which is recessed from a side of the wall portion facing the electrode assembly in a direction away from the electrode assembly.
  • the connecting portion is formed between the bottom surface of the first recess and the bottom surface of the second recess.
  • the reinforcement part further includes a second protrusion protruding from the bottom surface of the second recess, and at least part of the second protrusion is accommodated in the second recess.
  • the connecting portion is formed by opening the first concave portion and the second concave portion, which can reduce the depth requirements of the first concave portion and the second concave portion, and reduce the difficulty of forming.
  • the thickness of the reinforcing part can be further increased by providing the second convex part.
  • the main body portion includes a body portion, the body portion includes an inner surface and an outer surface disposed oppositely, the inner surface faces the electrode assembly, and the first recess is recessed from the outer surface in a direction facing the electrode assembly.
  • the second protrusion protrudes from the inner surface.
  • the second convex portion protrudes from the inner surface, so that the maximum thickness of the reinforcement portion is greater than the maximum thickness of the main body portion.
  • the main body further includes a third protrusion protruding from the inner surface, the second recess is recessed from the top surface of the third protrusion in a direction away from the electrode assembly, and the third protrusion surrounds the second recess outside.
  • the third convex part can not only play a reinforcing role in the position of the wall where the second concave part is formed, but also increase the depth of the second concave part to provide more material for the reinforcing part.
  • the second protrusion is entirely accommodated within the second recess.
  • the second concave part can completely accommodate the second convex part, which can reduce the risk of the second convex part interfering with other structures inside the battery cell.
  • the top surface of the second protrusion is flush with the top surface of the third protrusion.
  • the bottom surface of the second concave portion is closer to the electrode assembly than the inner surface in the thickness direction of the wall portion.
  • the above solution makes the bottom surface of the second concave part closer to the electrode assembly than the inner surface, so as to increase the distance between the bottom surface of the first concave part and the outer surface, reduce the risk of the weak area of the connecting part being damaged by external components, and improve the safety of the battery cell and service life.
  • the reinforcing part is provided with a third concave part, and the third concave part extends from the top end surface of the second convex part in a direction away from the electrode assembly. In the thickness direction of the wall portion, the distance between the bottom surface of the third concave portion and the top end surface of the first convex portion is greater than the maximum thickness of the main body portion.
  • the internal space of the battery cell can be increased by opening the third recess, so that more electrolyte can be accommodated inside the casing, and the performance of the battery cell can be improved.
  • the thickness of the part of the reinforcing part between the bottom surface of the third concave part and the top surface of the first convex part is greater than the maximum thickness of the main part, so as to ensure that the strength of the reinforcing part meets the requirements.
  • the depth of the third concave portion is smaller than the dimension of the second convex portion protruding from the bottom surface of the second concave portion.
  • the above solution controls the depth of the third recess so that the thickness of the portion of the reinforcement between the bottom surface of the third recess and the top end of the first protrusion is greater than the maximum thickness of the main body to ensure that the strength of the reinforcement meets the requirements.
  • the connecting portion is provided with a groove, so as to form a weakened area in a region corresponding to the groove.
  • a groove is provided on the connecting portion to form a weakened area on the connecting portion, so that the strength of the weakened area is lower than that of other regions of the connecting portion.
  • the wall portion further includes: a bent portion surrounding the outer side of the main body portion and extending in a direction facing the electrode assembly, so as to form a fourth concave portion on a side of the main body portion facing the electrode assembly; and a plate body portion , surrounding the outer side of the bent portion, the fourth concave portion is recessed relative to the surface of the plate body facing the electrode assembly.
  • the fourth recess by providing the fourth recess, the internal space of the battery cell can be increased, and the capacity of the battery cell can be increased.
  • the fourth recess can also provide a space for the reinforcing part, so that the reinforcing part has sufficient thickness.
  • the housing includes a housing and an end cover, the housing has an opening, and the end cover is used to cover the opening of the housing.
  • the end cap is the wall portion.
  • the end cap is a unitary structure.
  • the connection part and the reinforcement part with pressure relief function are integrated on the end cover, so as to simplify the structure of the battery cell.
  • an embodiment of the present application provides a battery, including a plurality of battery cells in any embodiment of the first aspect.
  • an embodiment of the present application provides an electrical device, including the battery cell in any embodiment of the first aspect, and the battery cell is used to provide electric energy.
  • the embodiment of the present application provides a method for manufacturing a battery cell, including:
  • a housing includes a wall portion, the wall portion includes a main body portion, a connection portion and a reinforcement portion, the connection portion surrounds the outside of the reinforcement portion, and the main body portion surrounds the outside of the connection portion;
  • connection part is provided with a weak area, and the battery cell is configured to rupture along the weak area when the internal pressure of the battery cell reaches a threshold value, so as to release the internal pressure; the maximum thickness of the reinforcement part is greater than the maximum thickness of the main part to reduce the pressure. Deformation of small reinforcements under internal pressure.
  • the embodiment of the present application provides a battery cell manufacturing system, including:
  • the second providing device is used to provide the shell, the shell includes a wall, the wall includes a main body, a connecting portion and a reinforcing portion, the connecting portion surrounds the outer side of the reinforcing portion, and the main body surrounds the outer side of the connecting portion;
  • connection part is provided with a weak area, and the battery cell is configured to rupture along the weak area when the internal pressure of the battery cell reaches a threshold value, so as to release the internal pressure; the maximum thickness of the reinforcement part is greater than the maximum thickness of the main part to reduce the pressure. Deformation of small reinforcements under internal pressure.
  • Fig. 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application.
  • Fig. 2 is a schematic explosion diagram of a battery provided by some embodiments of the present application.
  • FIG. 3 is an explosion schematic diagram of the battery module shown in FIG. 2;
  • Fig. 4 is a schematic explosion diagram of a battery cell provided by some embodiments of the present application.
  • Fig. 5 is a schematic structural view of the end cap shown in Fig. 4;
  • Fig. 6 is a schematic cross-sectional view of the end cap shown in Fig. 5;
  • Fig. 7 is an enlarged schematic view of the end cap shown in Fig. 6 at the circle frame A;
  • Fig. 8 is a partial cross-sectional view of an end cap of a battery cell provided by another embodiment of the present application.
  • FIG. 9 is a schematic flowchart of a method for manufacturing a battery cell provided in some embodiments of the present application.
  • Fig. 10 is a schematic block diagram of a battery cell manufacturing system provided by some embodiments of the present application.
  • connection In the description of this application, it should be noted that, unless otherwise clearly stipulated and limited, the terms “installation”, “connection”, “connection” and “attachment” should be understood in a broad sense, for example, it may be a fixed connection, It can also be detachably connected or integrally connected; it can be directly connected or indirectly connected through an intermediary, and it can be internal communication between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application according to specific situations.
  • “Plurality” in this application refers to two or more (including two).
  • the battery cells may include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, etc.
  • the embodiment of the present application does not limit this.
  • the battery cell can be in the form of a cylinder, a flat body, a cuboid or other shapes, which is not limited in this embodiment of the present application.
  • the battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.
  • the battery mentioned in this application may include a battery module or a battery pack, and the like.
  • Batteries generally include a case for enclosing one or more battery cells. The box can prevent liquid or other foreign objects from affecting the charging or discharging of the battery cells.
  • the battery cell includes an electrode assembly and an electrolyte, and the electrode assembly includes a positive pole piece, a negative pole piece and a separator.
  • a battery cell works primarily by moving metal ions between the positive and negative pole pieces.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode current collector; the positive electrode current collector includes a positive electrode coating area and a positive electrode tab connected to the positive electrode coating area, and the positive electrode coating area It is coated with a positive electrode active material layer, and the positive electrode tab is not coated with a positive electrode active material layer.
  • the material of the positive electrode current collector can be aluminum
  • the positive electrode active material layer includes the positive electrode active material
  • the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate.
  • the negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector;
  • the negative electrode current collector includes a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area, and the negative electrode coating area The negative electrode active material layer is coated, and the negative electrode tab is not coated with the negative electrode active material layer.
  • the material of the negative electrode current collector may be copper, the negative electrode active material layer includes the negative electrode active material, and the negative electrode active material may be carbon or silicon.
  • the material of the spacer can be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene).
  • the battery cell also includes a casing, and an accommodating cavity for accommodating the electrode assembly is formed inside the casing.
  • the casing can protect the electrode assembly from the outside, so as to prevent external foreign matter from affecting the charging or discharging of the electrode assembly.
  • the pressure relief mechanism on the battery cell has an important impact on the safety of the battery cell. For example, when a short circuit, overcharge, etc. occur, it may cause thermal runaway inside the battery cell and a sudden increase in pressure. In this case, the internal pressure can be released outward by actuating the pressure relief mechanism to prevent the battery cells from exploding and igniting.
  • the pressure relief mechanism refers to an element or part that is activated to release the internal pressure when the internal pressure of the battery cell reaches a predetermined threshold.
  • the threshold design varies according to design requirements. The threshold may depend on the materials of one or more of the positive pole piece, the negative pole piece, the electrolyte and the separator in the battery cell.
  • the pressure relief mechanism can take the form of an explosion-proof valve, gas valve, pressure relief valve or safety valve, etc., and can specifically adopt a pressure sensitive element or structure, that is, when the internal pressure of the battery cell reaches a predetermined threshold, the pressure relief mechanism executes The action or the weakened area in the pressure relief mechanism ruptures, thereby forming an opening or passage for the internal pressure to escape.
  • the "activation" mentioned in this application means that the pressure relief mechanism is activated or activated to a certain state, so that the internal pressure of the battery cell can be released. Actions by the pressure relief mechanism may include, but are not limited to, at least a portion of the pressure relief mechanism rupture, shatter, be torn, or open, among others.
  • the pressure relief mechanism When the pressure relief mechanism is actuated, the high-temperature and high-pressure material inside the battery cell will be discharged from the actuated part as discharge. In this manner, the battery cells can be depressurized under controllable pressure, thereby avoiding potential more serious accidents.
  • the emissions from battery cells mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrodes, fragments of separators, high-temperature and high-pressure gases generated by reactions, flames, etc.
  • the inventors tried to integrate the pressure relief mechanism into the casing.
  • the inventors formed a weakened area on the casing for rupture to release the internal pressure of the battery cell when the internal pressure reaches a threshold value.
  • a short circuit, overcharge, etc. it may cause thermal runaway inside the battery cell and a sudden increase in pressure.
  • the rupture of the weak area forms a channel to release the internal pressure, reducing the risk of explosion and fire of the battery cell. , thereby improving security.
  • the thickness of the weakened zone is directly related to the internal pressure required for the actuation of the weakened zone (hereinafter simply referred to as the actuation pressure).
  • the inventors have found through research that in order to enable the weak zone to rupture under the actuation pressure, the weak zone usually has a small thickness; in the later stage of the battery cell cycle, the weak zone is easily broken due to the long-term corrosion of the electrolyte, thereby causing electrolysis Liquid leakage, causing safety risks; the strength of the weak area is low, and when the battery cell is subjected to external impact, the weak area is also easy to rupture, resulting in the failure of the battery cell; the smaller the thickness of the weak area, the uniformity of its thickness during the molding process The resistance is also worse, which affects the consistency of the actuation pressure in different parts of the weakened zone.
  • the embodiment of the present application provides a technical solution, in which the battery cell includes a casing and an electrode assembly accommodated in the casing.
  • the shell includes a wall portion, the wall portion includes a main body portion, a connecting portion and a reinforcing portion, the connecting portion surrounds the outer side of the reinforcing portion, and the main body portion surrounds the outer side of the connecting portion.
  • the connecting portion is provided with a weakened area, and the battery cell is configured to rupture along the weakened area to release the internal pressure when the internal pressure of the battery cell reaches a threshold value.
  • the maximum thickness of the reinforcing part is greater than that of the main body, so as to reduce the deformation of the reinforcing part under the action of internal pressure.
  • Electric devices can be vehicles, mobile phones, portable devices, notebook computers, ships, spacecraft, electric toys and electric tools, and so on.
  • Vehicles can be fuel vehicles, gas vehicles or new energy vehicles, and new energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles;
  • spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.;
  • electric toys include fixed Type or mobile electric toys, such as game consoles, electric car toys, electric boat toys and electric airplane toys, etc.;
  • electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, for example, Electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, electric planers, and more.
  • the embodiments of the present application do not impose special limitations on the above-mentioned electrical devices.
  • the electric device is taken as an example for description.
  • Fig. 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application.
  • a battery 2 is arranged inside the vehicle 1 , and the battery 2 can be arranged at the bottom, head or tail of the vehicle 1 .
  • the battery 2 can be used for power supply of the vehicle 1 , for example, the battery 2 can be used as an operating power source of the vehicle 1 .
  • the vehicle 1 may further include a controller 3 and a motor 4 , the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements for starting, navigating, and driving of the vehicle 1 .
  • the battery 2 can not only be used as an operating power source for the vehicle 1 , but can also be used as a driving power source for the vehicle 1 to provide driving power for the vehicle 1 instead of or partially replacing fuel oil or natural gas.
  • Fig. 2 is a schematic explosion diagram of a battery provided by some embodiments of the present application.
  • the battery 2 includes a case body 5 and battery cells (not shown), and the battery cells are housed in the case body 5 .
  • the box body 5 is used to accommodate the battery cells, and the box body 5 may have various structures.
  • the box body 5 may include a first box body part 5a and a second box body part 5b, the first box body part 5a and the second box body part 5b cover each other, the first box body part 5a and the second box body part 5a
  • the two box parts 5b jointly define an accommodating space 5c for accommodating the battery cells.
  • the second box body part 5b can be a hollow structure with one end open, the first box body part 5a is a plate-shaped structure, and the first box body part 5a covers the opening side of the second box body part 5b to form an accommodating space 5c
  • the box body 5; the first box body portion 5a and the second box body portion 5b also can be a hollow structure with one side opening, and the opening side of the first box body portion 5a is covered on the opening side of the second box body portion 5b , to form a box body 5 with an accommodating space 5c.
  • the first box body part 5a and the second box body part 5b can be in various shapes, such as a cylinder, a cuboid, and the like.
  • a sealant such as sealant, sealing ring, etc.
  • a sealant can also be arranged between the first box body part 5a and the second box body part 5b.
  • the first box part 5a covers the top of the second box part 5b
  • the first box part 5a can also be called an upper box cover
  • the second box part 5b can also be called a lower box.
  • the battery 2 there may be one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, in parallel or in parallel.
  • the hybrid connection means that there are both series and parallel connections among the multiple battery cells.
  • a plurality of battery cells can be directly connected in series or in parallel or mixed together, and then the whole composed of a plurality of battery cells is accommodated in the box 5; of course, it is also possible to first connect a plurality of battery cells in series or parallel or
  • the battery modules 6 are formed by parallel connection, and multiple battery modules 6 are connected in series or in parallel or in series to form a whole, and are housed in the box body 5 .
  • FIG. 3 is an exploded schematic diagram of the battery module shown in FIG. 2 .
  • FIG. 3 there are multiple battery cells 7 , and the multiple battery cells 7 are connected in series, in parallel, or in parallel to form a battery module 6 .
  • a plurality of battery modules 6 are connected in series, in parallel or in parallel to form a whole, and accommodated in the box.
  • the plurality of battery cells 7 in the battery module 6 can be electrically connected through a confluence component, so as to realize parallel connection, series connection or mixed connection of the plurality of battery cells 7 in the battery module 6 .
  • Fig. 4 is a schematic exploded view of a battery cell provided by some embodiments of the present application.
  • the battery cell 7 includes a case 20 and an electrode assembly 10 accommodated in the case 20 .
  • the electrode assembly 10 is the core component for the battery cell 7 to realize the charge and discharge function, and it includes a positive pole piece, a negative pole piece and a separator.
  • the polarity of the positive pole piece and the negative pole piece is opposite, and the separator is used to connect the positive pole piece
  • the negative pole piece is insulated and isolated.
  • the electrode assembly 10 mainly relies on the movement of metal ions between the positive pole piece and the negative pole piece to work.
  • Electrode assembly 10 There can be one electrode assembly 10 or a plurality of them. When there are multiple electrode assemblies 10, the plurality of electrode assemblies 10 may be stacked. Exemplarily, as shown in FIG. 4 , there are four electrode assemblies 10 .
  • the casing 20 is a hollow structure, and an accommodating cavity for accommodating the electrode assembly 10 and electrolyte is formed inside.
  • the housing 20 can be in various shapes, such as cylinder, cuboid and so on.
  • the shape of the casing 20 may be determined according to the specific shape of the electrode assembly 10 . For example, if the electrode assembly 10 has a cylindrical structure, a cylindrical shell can be selected; if the electrode assembly 10 has a rectangular parallelepiped structure, a rectangular parallelepiped shell can be selected.
  • the housing 20 includes a casing 21 and an end cover 22 , the casing 21 has an opening, and the end cover 22 covers the opening.
  • the housing 21 can be a structure with one side opening, and the end cover 22 is provided as one and covers the opening of the housing 21 .
  • the housing 21 can also be a structure with openings on both sides, and there are two end caps 22 , and the two end caps 22 respectively cover the two openings of the housing 21 .
  • the end cover 22 is connected to the housing 21 by welding, bonding, clamping or other means.
  • the housing 21 has a structure with one side open and includes a bottom wall and at least one side wall connected to the bottom wall, and the side wall surrounds the bottom wall.
  • the housing 21 is a cylindrical housing.
  • the casing 21 includes a cylindrical side wall, one end of the side wall is connected to the bottom wall, and the other end encloses an opening opposite to the bottom wall.
  • the casing 21 is a cuboid casing. Specifically, the casing 21 includes four flat sidewalls, and the four sidewalls enclose an opening opposite to the bottom wall.
  • the battery cell 7 further includes two electrode terminals 30 , and the two electrode terminals 30 may be disposed on the end cap 22 .
  • the two electrode terminals 30 are a positive electrode terminal and a negative electrode terminal, respectively.
  • the positive electrode terminal is used for electrical connection with the positive pole piece of the electrode assembly 10
  • the negative electrode terminal is used for electrical connection with the negative pole piece, so as to lead out the electric energy generated by the electrode assembly 10 to the outside of the shell 20 .
  • each electrode terminal 30 is provided with a corresponding connecting member 40, or also called a current collecting member, which is located between the end cap 22 and the electrode assembly 10, and is used to connect the electrode terminal 30 to the corresponding pole. chip electrical connection.
  • FIG. 5 is a schematic structural view of the end cap shown in FIG. 4;
  • FIG. 6 is a schematic cross-sectional view of the end cap shown in FIG. 5;
  • FIG. 7 is an enlarged schematic view of the end cap shown in FIG.
  • the battery cell 7 provided by the embodiment of the present application includes a casing 20 and an electrode assembly 10 housed in the casing 20 .
  • the housing 20 includes a wall portion, the wall portion includes a main body portion 23 , a connecting portion 24 and a reinforcing portion 25 , the connecting portion 24 surrounds the reinforcing portion 25 outside, and the main body portion 23 surrounds the connecting portion 24 outside.
  • the connection part 24 is provided with a weakened area 241, and the battery cell 7 is configured to burst along the weak area 241 when the internal pressure of the battery cell 7 reaches a threshold value, so as to release the internal pressure.
  • the maximum thickness of the reinforcement part 25 is greater than the maximum thickness of the main body part 23 to reduce the deformation of the reinforcement part 25 under the action of internal pressure.
  • the wall portion may be an end cap 22 .
  • the wall portion may be a part of the housing 21 , for example, the wall portion may be a side wall of the housing 21 or a bottom wall of the housing 21 .
  • the connecting portion 24 is an annular structure and is connected between the main body portion 23 and the reinforcement portion 25 .
  • the inner end of the connection part 24 is connected to the reinforcement part 25 , and the outer end is connected to the main body part 23 .
  • the strength of the weakened area 241 is lower than the strength of the main body portion 23 , the reinforcement portion 25 and other regions of the connecting portion 24 .
  • the thickness of the weakened area 241 is smaller than the thickness of the main body portion 23 , the reinforcement portion 25 and other regions of the connection portion 24 .
  • the thickness and strength of the weak region 241 can be reduced by providing structures such as grooves and notches on the connecting portion 24 , so that the weak region 241 can rupture when the internal pressure of the battery cell 7 reaches a threshold.
  • the thickness of the reinforcement part 25 refers to the dimension of the reinforcement part 25 in the thickness direction Z of the wall part
  • the thickness of the main body part 23 refers to the dimension of the main part 23 in the thickness direction Z of the wall part. In the description of the embodiments of the present application, the thickness refers to the dimension of the solid part along the thickness direction Z.
  • the connecting portion 24 and the reinforcing portion 25 constitute a pressure relief mechanism for the battery cell 7 .
  • the reinforcing part 25 can be completely separated from the main part 23 under the action of internal pressure, or can be kept connected with the main part 23 and folded outward.
  • the walls are deformed by the internal pressure.
  • the main body portion 23 has a smaller thickness than the reinforcing portion 25 , so under the action of internal pressure, the main body portion 23 is more likely to deform relative to the reinforcing portion 25 .
  • the stress is transmitted to the connecting part 24, and because the thickness of the reinforcing part 25 is relatively large and not easily deformed, it is difficult for the reinforcing part 25 to release the stress on the connecting part 24 through deformation. As a result of this stress and internal pressure, it is more likely to rupture.
  • this embodiment can increase the thickness of the weakened region 241 without changing the internal pressure required for the rupture of the weakened region 241, thereby reducing the risk of the weakened region 241 being ruptured during normal use. risk, prolong the service life of the battery cell 7, and improve the safety of the battery cell 7.
  • this embodiment can increase the thickness of the weak zone 241, which simplifies the molding process of the weak zone 241, improves the uniformity of its thickness during the molding process, and ensures that different parts of the weak zone 241 are broken. The consistency of the internal pressure.
  • the wall portion includes a first concave portion 26 , and the first concave portion 26 is recessed from a side of the wall portion away from the electrode assembly 10 in a direction facing the electrode assembly 10 .
  • the reinforcement part 25 includes a first protrusion 251 protruding from the bottom surface of the first recess 26 , and at least part of the first protrusion 251 is accommodated in the first recess 26 .
  • the connecting portion 24 is formed in a region corresponding to the bottom surface of the first concave portion 26 .
  • the first recess 26 is opened at an end facing away from the electrode assembly 10 .
  • the first protrusion 251 may be entirely accommodated within the first recess 26 . In some other examples, the first protrusion 251 may also protrude out of the first recess 26 , and the first protrusion 251 is only partially accommodated in the first recess 26 .
  • At least part of the bottom surface of the first concave portion 26 is a surface of the connection portion 24 facing away from the electrode assembly 10 .
  • the thickness of the connecting portion 24 is reduced by opening the first concave portion 26 on the wall, thereby reducing the strength of the weakened region 241 so that the weakened region 241 can rupture when the internal pressure of the battery cell 7 reaches a threshold.
  • the first recess 26 may be formed by extruding a wall portion. During extrusion molding, a part of the material of the wall part flows to the reinforcement part 25 to increase the thickness and strength of the reinforcement part 25 .
  • the bottom surface of the first concave portion 26 is a plane perpendicular to the thickness direction Z.
  • the first protrusion 251 is entirely accommodated in the first recess 26 .
  • the first concave portion 26 can completely accommodate the first convex portion 251 , which can prevent the first convex portion 251 from increasing the maximum dimension of the casing 20 in the thickness direction Z and increase the energy density of the battery cell 7 .
  • the depth of the first concave portion 26 is equal to the dimension by which the first protrusion 251 protrudes from the bottom surface of the first concave portion 26 .
  • the wall portion further includes a second concave portion 27 , which is recessed from a side of the wall portion facing the electrode assembly 10 in a direction away from the electrode assembly 10 .
  • the connecting portion 24 is formed between the bottom surface of the first concave portion 26 and the bottom surface of the second concave portion 27.
  • the reinforcement part 25 further includes a second protrusion 252 protruding from the bottom surface of the second recess 27 , and at least part of the second protrusion 252 is accommodated in the second recess 27 .
  • the second recess 27 is opened at one end facing the electrode assembly 10 .
  • the second convex portion 252 may be entirely accommodated in the second concave portion 27 .
  • the second protrusion 252 may also protrude out of the second recess 27 , and the second protrusion 252 is only partially accommodated in the second recess 27 .
  • the connecting portion 24 is formed by opening the first concave portion 26 and the second concave portion 27 , which can reduce the requirement for the depth of the first concave portion 26 and the second concave portion 27 and reduce the difficulty of forming.
  • the thickness of the reinforcing part 25 can be further increased by providing the second convex part 252 .
  • the second recess 27 is formed by extruding the wall. During extrusion molding, a part of the material of the wall part flows to the reinforcement part 25 to increase the thickness and strength of the reinforcement part 25 .
  • the main body portion 23 includes a body portion 231, the body portion 231 includes an inner surface 231a and an outer surface 231b oppositely disposed, the inner surface 231a faces the electrode assembly 10, and the first concave portion 26 faces the electrode assembly 10 along the outer surface 231b.
  • the second protrusion 252 protrudes from the inner surface 231a.
  • the inner surface 231 a and the outer surface 231 b are oppositely disposed along the thickness direction Z, the inner surface 231 a faces the electrode assembly 10 and the outer surface 231 b faces away from the electrode assembly 10 .
  • both the inner surface 231 a and the outer surface 231 b are planes perpendicular to the thickness direction Z, and the distance between the inner surface 231 a and the outer surface 231 b is the thickness of the main body portion 231 .
  • the second convex portion 252 protrudes from the inner surface 231 a, so that the maximum thickness of the reinforcement portion 25 is greater than the maximum thickness of the main body portion 231 .
  • the first protrusion 251 does not protrude from the outer surface 231b; for example, the outer surface 231b is flush with the top surface of the first protrusion 251 .
  • the main body portion 23 further includes a third convex portion 232 protruding from the inner surface 231a, the second concave portion 27 is recessed from the top surface of the third convex portion 232 in a direction away from the electrode assembly 10, and the third convex portion The portion 232 surrounds the outside of the second concave portion 27 .
  • the third convex portion 232 can not only play a reinforcing role in the position where the second concave portion 27 is formed on the wall, but also increase the depth of the second concave portion 27 to provide more material for the reinforcing portion 25 .
  • the second convex portion 252 is entirely accommodated in the second concave portion 27 .
  • the second concave portion 27 can completely accommodate the second convex portion 252 , which can reduce the risk of the second convex portion 252 interfering with other structures inside the battery cell 7 .
  • the top surface of the second protrusion 252 is flush with the top surface of the third protrusion 232 .
  • both the top end surface of the second protrusion 252 and the top end surface of the third protrusion 232 are planes perpendicular to the thickness direction Z.
  • the thickness of the reinforcing portion 25 can be increased as much as possible without increasing the maximum dimension of the wall portion along the thickness direction Z.
  • the bottom surface of the second concave portion 27 is closer to the electrode assembly 10 than the inner surface 231a.
  • the bottom surface of the second concave portion 27 is closer to the electrode assembly 10 than the inner surface 231a, so as to increase the distance between the bottom surface of the first concave portion 26 and the outer surface 231b, and reduce the risk of the weak region 241 of the connecting portion 24 being damaged by external components , improving the safety and service life of the battery cell 7 .
  • the reinforcing part 25 is provided with a third concave part 253 , and the third concave part 253 extends from the top surface of the second convex part 252 in a direction away from the electrode assembly 10 .
  • the distance between the bottom surface of the third concave portion 253 and the top end surface of the first convex portion 251 is greater than the maximum thickness of the main body portion 23 .
  • the bottom surface of the third concave portion 253 is parallel to the top surface of the first convex portion 251 .
  • the internal space of the battery cell 7 can be increased by opening the third recess 253 , so that more electrolyte can be accommodated inside the casing 20 and the performance of the battery cell 7 can be improved.
  • the thickness of the reinforcement part 25 between the bottom surface of the third concave part 253 and the top surface of the first convex part 251 is greater than the maximum thickness of the main body part 23 to ensure that the strength of the reinforcement part 25 meets the requirement.
  • the third recess 253 may be formed by pressing the reinforcing part 25 . During the extrusion molding process, a part of the material of the reinforcement part 25 moves and gathers to the part around the third concave part 253 , so as to increase the maximum thickness and strength of the reinforcement part 25 locally.
  • the depth of the third concave portion 253 is smaller than the dimension of the second convex portion 252 protruding from the bottom surface of the second concave portion 27 .
  • the thickness of the part of the reinforcement portion 25 between the bottom surface of the third concave portion 253 and the top end surface of the first convex portion 251 is greater than the maximum thickness of the main body portion 23 to ensure reinforcement.
  • the strength of the portion 25 meets the requirements.
  • the connecting portion 24 is provided with a groove 242 to form a weakened area 241 in a region corresponding to the groove 242 .
  • the groove 242 can be provided on the surface of the connection part 24 facing the electrode assembly 10 , or can be provided on the surface of the connection part 24 facing away from the electrode assembly 10 .
  • the weakened area 241 and the groove 242 are correspondingly arranged.
  • a machining method may be used to remove material on the connecting portion 24 to form the groove 242 , which is beneficial to reduce processing cost and processing difficulty.
  • the groove 242 may also be formed by extruding the connecting portion 24 .
  • a groove 242 is provided on the connecting portion 24 to form a weakened region 241 on the connecting portion 24 , so that the strength of the weakened region 241 is lower than that of other regions of the connecting portion 24 .
  • the wall portion further includes a bent portion 28 and a plate portion 29 .
  • the bent portion 28 surrounds the outer side of the main body 23 and extends along a direction facing the electrode assembly 10 to form a fourth concave portion 29 a on a side of the main body 23 facing the electrode assembly 10 .
  • the plate body portion 29 surrounds the outer side of the bent portion 28 , and the fourth concave portion 29 a is recessed relative to the surface of the plate body portion 29 facing the electrode assembly 10 .
  • the wall portion is an end cap 22
  • the plate body portion 29 is used to connect to the housing 21 .
  • the fourth concave portion 29 a by providing the fourth concave portion 29 a, the internal space of the battery cell 7 can be increased, and the capacity of the battery cell 7 can be increased.
  • the fourth concave portion 29 a can also provide a space for the reinforcement portion 25 , so that the reinforcement portion 25 has sufficient thickness.
  • the maximum thickness of the reinforcement part 25 is greater than the maximum thickness of the plate body part 29 and the maximum thickness of the bending part 28 .
  • the housing 20 includes a housing 21 and an end cover 22 , the housing 21 has an opening, and the end cover 22 is used to cover the opening of the housing 21 .
  • the end cap 22 is a wall.
  • the end cap 22 is a unitary structure.
  • connection part 24 and the reinforcement part 25 with pressure relief function are integrated on the end cover 22 to simplify the structure of the battery cell 7 .
  • Fig. 8 is a partial cross-sectional view of an end cover of a battery cell provided by another embodiment of the present application.
  • the reinforcement part 25 protrudes from the surface of the main body part 23 facing the electrode assembly 10 .
  • the reinforcing part 25 protrudes toward the electrode assembly 10 to increase the thickness and strength of the reinforcing part 25 .
  • the surface of the main body part 23 facing the electrode assembly 10 and the surface of the connection part 24 facing the electrode assembly 10 are flush.
  • FIG. 9 is a schematic flowchart of a method for manufacturing a battery cell provided by some embodiments of the present application.
  • the manufacturing method of the battery cell in the embodiment of the present application includes:
  • the casing includes a wall, the wall includes a main body, a connecting portion, and a reinforcing portion, the connecting portion surrounds the outer side of the reinforcing portion, and the main body surrounds the outer side of the connecting portion;
  • connection part is provided with a weak area, and the battery cell is configured to rupture along the weak area when the internal pressure of the battery cell reaches a threshold value, so as to release the internal pressure; the maximum thickness of the reinforcement part is greater than the maximum thickness of the main part to reduce the pressure. Deformation of small reinforcements under internal pressure.
  • Fig. 10 is a schematic block diagram of a battery cell manufacturing system provided by some embodiments of the present application.
  • the battery cell manufacturing system 90 of the embodiment of the present application includes a first providing device 91 , a second providing device 92 and an assembling device 93 .
  • the first providing device 91 is used to provide the electrode assembly;
  • the second providing device 92 is used to provide the casing, the casing includes a wall, the wall includes a main body, a connecting part and a reinforcing part, the connecting part surrounds the outer side of the reinforcing part, and the main part surrounds On the outside of the connection part;
  • the assembly device 93 is used to install the electrode assembly into the casing.
  • connection part is provided with a weak area, and the battery cell is configured to rupture along the weak area when the internal pressure of the battery cell reaches a threshold value to release the internal pressure; the maximum thickness of the reinforcement part is greater than the maximum thickness of the main part to reduce the reinforcement The deformation of the part under the action of internal pressure.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Sealing Battery Cases Or Jackets (AREA)

Abstract

本申请实施例提供一种电池单体及其制造方法和制造系统、电池以及用电装置。电池单体包括外壳和容纳于外壳内的电极组件。外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧。连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力。加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。本申请能够降低薄弱区在正常使用过程中破裂的风险，延长电池单体的使用寿命，提高电池单体的安全性。

Description

电池单体及其制造方法和制造系统、电池以及用电装置 技术领域
本申请涉及电池技术领域，并且更具体地，涉及一种电池单体及其制造方法和制造系统、电池以及用电装置。
背景技术
电池单体广泛用于电子设备，例如手机、笔记本电脑、电瓶车、电动汽车、电动飞机、电动轮船、电动玩具汽车、电动玩具轮船、电动玩具飞机和电动工具等等。电池单体可以包括镉镍电池单体、氢镍电池单体、锂离子电池单体和二次碱性锌锰电池单体等。
在电池技术的发展中，除了提高电池单体的性能外，安全问题也是一个不可忽视的问题。如果电池单体的安全问题不能保证，那该电池单体就无法使用。因此，如何增强电池单体的安全性，是电池技术中一个亟待解决的技术问题。
发明内容
本申请提供了一种电池单体及其制造方法和制造系统、电池以及用电装置，其能提高电池单体的安全性。
第一方面，本申请实施例提供了一种电池单体，包括外壳和容纳于外壳内的电极组件。外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧。连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力。加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。
在电池单体出现热失控时，壁部在内部压力的作用下变形。在上述方案中，主体部相对于加强部的具有较小的厚度，所以在内部压力的作用下，主体部相对于加强部更容易发生变形。主体部变形时应力传递到连接部上，而由于加强部的厚度较大且不易变形，所以加强部难以通过变形来释放连接部上的应力，这样，薄弱区要同时承 受该应力和内部压力的作用，其更容易破裂。因此，相对于传统的泄压机构，上述方案能够在不改变薄弱区破裂所需的内部压力的前提下，增大薄弱区的厚度，从而降低薄弱区在正常使用过程中破裂的风险，延长电池单体的使用寿命，提高电池单体的安全性。
在一些实施例中，壁部包括第一凹部，第一凹部从壁部背离电极组件的一侧沿面向电极组件的方向凹陷。加强部包括凸出于第一凹部的底面的第一凸部，第一凸部的至少部分容纳于第一凹部内。连接部形成于与第一凹部的底面相对应的区域。
上述方案通过在壁部上开设第一凹部来减小连接部的厚度，进而减小薄弱区的强度，以使薄弱区能够在电池单体的内部压力达到阈值时破裂。
在一些实施例中，第一凸部整体容纳于第一凹部内。第一凹部可以完全容纳第一凸部，这样可以避免第一凸部增大外壳在厚度方向上的最大尺寸，提高电池单体的能量密度。
在一些实施例中，加强部凸出于主体部面向电极组件的表面。上述方案使加强部面向电极组件凸出，以增大加强部的厚度和强度。
在一些实施例中，壁部还包括第二凹部，第二凹部从壁部面向电极组件的一侧沿背离电极组件的方向凹陷。连接部形成于第一凹部的底面和第二凹部的底面之间。加强部还包括凸出于第二凹部的底面的第二凸部，第二凸部的至少部分容纳于第二凹部内。
在连接部的厚度一定时，如果仅在连接部的一侧设置第一凹部，那么第一凹部的深度较大，第一凹部成型的难度较大。上述方案通过开设第一凹部和第二凹部来形成连接部，这样可以减小第一凹部和第二凹部对深度的要求，降低成型难度。上述方案通过设置第二凸部可以进一步增大加强部的厚度。
在一些实施例中，主体部包括本体部，本体部包括相对设置的内表面和外表面，内表面面向电极组件，第一凹部从外表面沿面向电极组件的方向凹陷。第二凸部凸出于内表面。上述方案的第二凸部凸出于内表面，以使加强部的最大厚度大于本体部的最大厚度。
在一些实施例中，主体部还包括凸出于内表面的第三凸部，第二凹部从第三凸部的顶端面沿背离电极组件的方向凹陷，且第三凸部环绕在第二凹部的外侧。
在上述方案中，第三凸部既可以在壁部的形成第二凹部的位置起到加强作用， 还可增大第二凹部凹陷的深度，为加强部提供更多的材料。
在一些实施例中，第二凸部整体容纳于第二凹部内。第二凹部可以完全容纳第二凸部，这样可以降低第二凸部与电池单体内部的其它结构干涉的风险。
在一些实施例中，第二凸部的顶端面和第三凸部的顶端面齐平。上述方案能够在不增大壁部沿厚度方向的最大尺寸的前提下，尽可能地增大加强部的厚度。
在一些实施例中，在壁部的厚度方向上，第二凹部的底面比内表面更靠近电极组件。
在连接部的厚度一定的前提下，第二凹部的底面越靠近电极组件，第一凹部的底面也就越靠近电极组件。上述方案使第二凹部的底面比内表面更靠近电极组件，以增大第一凹部的底面和外表面的距离，减小连接部的薄弱区被外部构件损伤的风险，提高电池单体的安全性和使用寿命。
在一些实施例中，加强部设有第三凹部，第三凹部从第二凸部的顶端面沿背离电极组件的方向延伸。在壁部的厚度方向上，第三凹部的底面和第一凸部的顶端面之间的距离大于主体部的最大厚度。
在上述方案中，通过开设第三凹部可以增大电池单体的内部空间，以使外壳内部能够容纳更多的电解液，改善电池单体的性能。加强部的位于第三凹部的底面和第一凸部的顶端面之间的部分的厚度大于主体部的最大厚度，以保证加强部的强度满足要求。
在一些实施例中，在壁部的厚度方向上，第三凹部的深度小于第二凸部凸出于第二凹部的底面的尺寸。
上述方案通过控制第三凹部的深度，以使加强部的位于第三凹部的底面和第一凸部的顶端面之间的部分的厚度大于主体部的最大厚度，保证加强部的强度满足要求。
在一些实施例中，连接部设有凹槽，以在与凹槽相对应的区域形成薄弱区。
上述方案通过在连接部上开设凹槽，以在连接部上形成薄弱区，使薄弱区的强度小于连接部的其它区域的强度。
在一些实施例中，壁部还包括：弯折部,环绕在主体部的外侧并沿面向电极组件的方向延伸，以在主体部的面向电极组件的一侧形成第四凹部；以及板体部，环绕在弯折部的外侧，第四凹部相对于板体部的面向电极组件的表面凹陷。
上述方案通过设置第四凹部，可以增大电池单体的内部空间，提高电池单体的 容量。同时，第四凹部还能够为加强部提供空间，使加强部具有足够的厚度。
在一些实施例中，外壳包括壳体和端盖，壳体具有开口，端盖用于盖合于壳体的开口。端盖为壁部。
在一些实施例中，端盖为一体形成结构。上述方案将具有泄压功能的连接部和加强部集成在端盖上，以简化电池单体的结构。
第二方面，本申请实施例提供了一种电池，包括多个第一方面任一实施例的电池单体。
第三方面，本申请实施例提供了一种用电装置，包括第一方面任一实施例的电池单体，电池单体用于提供电能。
第四方面，本申请实施例提供了一种电池单体的制造方法，包括：
提供电极组件；
提供外壳，外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧；
将电极组件安装到外壳内；
其中，连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力；加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。
第五方面，本申请实施例提供了一种电池单体的制造系统，包括：
第一提供装置，用于提供电极组件；
第二提供装置，用于提供外壳，外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧；
组装装置，用于将电极组件安装到外壳内；
其中，连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力；加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施例中所需要使用的附图作简单地介绍，显而易见地，下面所描述的附图仅仅是本申请的一些实施 例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
图1为本申请一些实施例提供的车辆的结构示意图；
图2为本申请一些实施例提供的电池的爆炸示意图；
图3为图2所示的电池模块的爆炸示意图；
图4为本申请一些实施例提供的电池单体的爆炸示意图；
图5为图4所示的端盖的结构示意图；
图6为图5所示的端盖的剖视示意图；
图7为图6所示的端盖在圆框A处的放大示意图；
图8为本申请另一些实施例提供的电池单体的端盖的局部剖视图；
图9为本申请一些实施例提供的电池单体的制造方法的流程示意图；
图10为本申请一些实施例提供的电池单体的制造系统的示意性框图。
在附图中，附图并未按照实际的比例绘制。
具体实施方式
为使本申请实施例的目的、技术方案和优点更加清楚，下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚地描述，显然，所描述的实施例是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
除非另有定义，本申请所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同；本申请中在申请的说明书中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本申请；本申请的说明书和权利要求书及上述附图说明中的术语“包括”和“具有”以及它们的任何变形，意图在于覆盖不排他的包含。本申请的说明书和权利要求书或上述附图中的术语“第一”、“第二”等是用于区别不同对象，而不是用于描述特定顺序或主次关系。
在本申请中提及“实施例”意味着，结合实施例描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其它实施例互斥的独立的或备选的实施例。
在本申请的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”、“附接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请中的具体含义。
本申请中术语“和/或”，仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本申请中字符“/”，一般表示前后关联对象是一种“或”的关系。
在本申请的实施例中，相同的附图标记表示相同的部件，并且为了简洁，在不同实施例中，省略对相同部件的详细说明。应理解，附图示出的本申请实施例中的各种部件的厚度、长宽等尺寸，以及集成装置的整体厚度、长宽等尺寸仅为示例性说明，而不应对本申请构成任何限定。
本申请中出现的“多个”指的是两个以上(包括两个)。
本申请中，电池单体可以包括锂离子二次电池单体、锂离子一次电池单体、锂硫电池单体、钠锂离子电池单体、钠离子电池单体或镁离子电池单体等，本申请实施例对此并不限定。电池单体可呈圆柱体、扁平体、长方体或其它形状等，本申请实施例对此也不限定。
本申请的实施例所提到的电池是指包括一个或多个电池单体以提供更高的电压和容量的单一的物理模块。例如，本申请中所提到的电池可以包括电池模块或电池包等。电池一般包括用于封装一个或多个电池单体的箱体。箱体可以避免液体或其他异物影响电池单体的充电或放电。
电池单体包括电极组件和电解液，电极组件包括正极极片、负极极片和隔离件。电池单体主要依靠金属离子在正极极片和负极极片之间移动来工作。正极极片包括正极集流体和正极活性物质层，正极活性物质层涂覆于正极集流体的表面；正极集流体包括正极涂覆区和连接于正极涂覆区的正极极耳，正极涂覆区涂覆有正极活性物质层，正极极耳未涂覆正极活性物质层。以锂离子电池单体为例，正极集流体的材料可以为铝，正极活性物质层包括正极活性物质，正极活性物质可以为钴酸锂、磷酸铁锂、三元锂或锰酸锂等。负极极片包括负极集流体和负极活性物质层，负极活性物质层涂覆于负极集流体的表面；负极集流体包括负极涂覆区和连接于负极涂覆区的负极极耳， 负极涂覆区涂覆有负极活性物质层，负极极耳未涂覆负极活性物质层。负极集流体的材料可以为铜，负极活性物质层包括负极活性物质，负极活性物质可以为碳或硅等。隔离件的材质可以为PP(polypropylene，聚丙烯)或PE(polyethylene，聚乙烯)等。
电池单体还包括外壳，外壳内部形成用于容纳电极组件的容纳腔。外壳可以从外侧保护电极组件，以避免外部的异物影响电极组件的充电或放电。
电池技术的发展要同时考虑多方面的设计因素，例如，能量密度、循环寿命、放电容量、充放电倍率等性能参数，另外，还需要考虑电池的安全性。
电池单体上的泄压机构对电池单体的安全性有着重要影响。例如，当发生短路、过充等现象时，可能会导致电池单体内部发生热失控从而压力骤升。这种情况下通过泄压机构致动可以将内部压力向外释放，以防止电池单体爆炸、起火。
泄压机构是指在电池单体的内部压力达到预定阈值时致动以泄放内部压力的元件或部件。该阈值设计根据设计需求不同而不同。该阈值可能取决于电池单体中的正极极片、负极极片、电解液和隔离件中一种或几种的材料。
泄压机构可以采用诸如防爆阀、气阀、泄压阀或安全阀等的形式，并可以具体采用压敏元件或构造，即，当电池单体的内部压力达到预定阈值时，泄压机构执行动作或者泄压机构中设有的薄弱区破裂，从而形成可供内部压力泄放的开口或通道。
本申请中所提到的“致动”是指泄压机构产生动作或被激活至一定的状态，从而使得电池单体的内部压力得以被泄放。泄压机构产生的动作可以包括但不限于：泄压机构中的至少一部分破裂、破碎、被撕裂或者打开，等等。泄压机构在致动时，电池单体的内部的高温高压物质作为排放物会从致动的部位向外排出。以此方式能够在可控压力的情况下使电池单体发生泄压，从而避免潜在的更严重的事故发生。
本申请中所提到的来自电池单体的排放物包括但不限于：电解液、被溶解或分裂的正负极极片、隔离件的碎片、反应产生的高温高压气体、火焰，等等。
为了简化电池单体的结构，发明人尝试将泄压机构集成到外壳上。例如，发明人在外壳上形成薄弱区，薄弱区用于在电池单体的内部压力达到阈值时破裂以泄放内部压力。当发生短路、过充等现象时，可能会导致电池单体内部发生热失控从而压力骤升，这种情况下通过薄弱区的破裂形成释放内部压力的通道，降低电池单体爆炸、起火的风险，从而提高安全性。
薄弱区的厚度和薄弱区致动所需的内部压力(以下简称为致动压力)直接相关联。发明人经过研究发现，为了使薄弱区能够在致动压力下破裂，薄弱区通常具有较小的厚度；在电池单体循环的后期，薄弱区因电解液的长期腐蚀而容易破裂，从而造成电解液泄露，引发安全风险；薄弱区的强度较低，在电池单体受到外部冲击时，薄弱区也容易破裂，导致电池单体失效；薄弱区的厚度越小，其在成型过程中厚度的均一性也就越差，这会影响薄弱区的不同部分的致动压力的一致性。
鉴于此，本申请实施例提供了一种技术方案，在该技术方案中，电池单体包括外壳和容纳于外壳内的电极组件。外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧。连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力。加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。本技术方案能够在不改变薄弱区破裂所需的内部压力的前提下，增大薄弱区的厚度，以降低薄弱区在正常使用过程中破裂的风险，延长电池单体的使用寿命，提高电池单体的安全性。
本申请实施例描述的技术方案适用于电池以及使用电池的用电装置。
用电装置可以是车辆、手机、便携式设备、笔记本电脑、轮船、航天器、电动玩具和电动工具等等。车辆可以是燃油汽车、燃气汽车或新能源汽车，新能源汽车可以是纯电动汽车、混合动力汽车或增程式汽车等；航天器包括飞机、火箭、航天飞机和宇宙飞船等等；电动玩具包括固定式或移动式的电动玩具，例如，游戏机、电动汽车玩具、电动轮船玩具和电动飞机玩具等等；电动工具包括金属切削电动工具、研磨电动工具、装配电动工具和铁道用电动工具，例如，电钻、电动砂轮机、电动扳手、电动螺丝刀、电锤、冲击电钻、混凝土振动器和电刨等等。本申请实施例对上述用电装置不做特殊限制。
以下实施例为了方便说明，以用电装置为车辆为例进行说明。
图1为本申请一些实施例提供的车辆的结构示意图。
如图1所示，车辆1的内部设置有电池2，电池2可以设置在车辆1的底部或头部或尾部。电池2可以用于车辆1的供电，例如，电池2可以作为车辆1的操作电源。
车辆1还可以包括控制器3和马达4，控制器3用来控制电池2为马达4供电， 例如，用于车辆1的启动、导航和行驶时的工作用电需求。
在本申请一些实施例中，电池2不仅仅可以作为车辆1的操作电源，还可以作为车辆1的驱动电源，代替或部分地代替燃油或天然气为车辆1提供驱动动力。
图2为本申请一些实施例提供的电池的爆炸示意图。
如图2所示，电池2包括箱体5和电池单体(未示出)，电池单体容纳于箱体5内。
箱体5用于容纳电池单体，箱体5可以是多种结构。在一些实施例中，箱体5可以包括第一箱体部5a和第二箱体部5b，第一箱体部5a与第二箱体部5b相互盖合，第一箱体部5a和第二箱体部5b共同限定出用于容纳电池单体的容纳空间5c。第二箱体部5b可以是一端开口的空心结构，第一箱体部5a为板状结构，第一箱体部5a盖合于第二箱体部5b的开口侧，以形成具有容纳空间5c的箱体5；第一箱体部5a和第二箱体部5b也均可以是一侧开口的空心结构，第一箱体部5a的开口侧盖合于第二箱体部5b的开口侧，以形成具有容纳空间5c的箱体5。当然，第一箱体部5a和第二箱体部5b可以是多种形状，比如，圆柱体、长方体等。
为提高第一箱体部5a与第二箱体部5b连接后的密封性，第一箱体部5a与第二箱体部5b之间也可以设置密封件，比如，密封胶、密封圈等。
假设第一箱体部5a盖合于第二箱体部5b的顶部，第一箱体部5a亦可称之为上箱盖，第二箱体部5b亦可称之为下箱体。
在电池2中，电池单体可以是一个，也可以是多个。若电池单体为多个，多个电池单体之间可串联或并联或混联，混联是指多个电池单体中既有串联又有并联。多个电池单体之间可直接串联或并联或混联在一起，再将多个电池单体构成的整体容纳于箱体5内；当然，也可以是多个电池单体先串联或并联或混联组成电池模块6，多个电池模块6再串联或并联或混联形成一个整体，并容纳于箱体5内。
图3为图2所示的电池模块的爆炸示意图。
在一些实施例中，如图3所示，电池单体7为多个，多个电池单体7先串联或并联或混联组成电池模块6。多个电池模块6再串联或并联或混联形成一个整体，并容纳于箱体内。
电池模块6中的多个电池单体7之间可通过汇流部件实现电连接，以实现电池模块6中的多个电池单体7的并联或串联或混联。
图4为本申请一些实施例提供的电池单体的爆炸示意图。
如图4所示，电池单体7包括外壳20和容纳于外壳20内的电极组件10。
电极组件10为电池单体7实现充放电功能的核心部件，其包括正极极片、负极极片和隔离件，正极极片和负极极片的极性相反，隔离件用于将正极极片和负极极片绝缘隔离。电极组件10主要依靠金属离子在正极极片和负极极片之间移动来工作。
电极组件10可以为一个，也可以为多个。当电极组件10为多个时，多个电极组件10可以层叠布置。示例性地，如图4所示，电极组件10为四个。
外壳20为空心结构，其内部形成用于容纳电极组件10和电解液的容纳腔。外壳20可以是多种形状，比如，圆柱体、长方体等。外壳20的形状可根据电极组件10的具体形状来确定。比如，若电极组件10为圆柱体结构，则可选用为圆柱体外壳；若电极组件10为长方体结构，则可选用长方体外壳。
在一些实施例中，外壳20包括壳体21和端盖22，壳体21具有开口，端盖22盖合于开口。
壳体21可为一侧开口的结构，端盖22设置为一个并盖合于壳体21的开口。可替代地，壳体21也可为两侧开口的结构，端盖22设置为两个，两个端盖22分别盖合于壳体21的两个开口。
示例性地，端盖22通过焊接、粘接、卡接或其它方式连接于壳体21。
在一些实施例中，壳体21为一侧开口的结构且包括底壁和连接于底壁的至少一个侧壁，且侧壁围设在底壁的周围。
在一些示例中，壳体21为圆柱状壳体。具体地，壳体21包括一个圆筒状的侧壁，侧壁的一端与底壁连接，另一端围成与底壁相对的开口。
在另一些示例中，壳体21为长方体状壳体。具体地，壳体21包括四个平板状的侧壁，四个侧壁围成与底壁相对的开口。
在一些实施例中，电池单体7还包括两个电极端子30，两个电极端子30可以设置在端盖22上。两个电极端子30分别为正电极端子和负电极端子。正电极端子用于与电极组件10的正极极片电连接，负电极端子用于与负极极片电连接，以将电极组件10产生的电能引出到外壳20外。
在一些实施例中，每个电极端子30各对应设置一个连接构件40，或者也可以称为集流构件，其位于端盖22与电极组件10之间，用于将电极端子30和对应的极片 电连接。
图5为图4所示的端盖的结构示意图；图6为图5所示的端盖的剖视示意图；图7为图6所示的端盖在圆框A处的放大示意图。
参照图4至图7，本申请实施例提供的电池单体7包括外壳20和容纳于外壳20内的电极组件10。外壳20包括壁部，壁部包括主体部23、连接部24和加强部25，连接部24环绕在加强部25的外侧，主体部23环绕在连接部24的外侧。连接部24设置有薄弱区241，电池单体7被配置为在电池单体7的内部压力达到阈值时沿薄弱区241破裂，以泄放内部压力。加强部25的最大厚度大于主体部23的最大厚度，以减小加强部25在内部压力的作用下的变形。
在本申请的一些示例中，壁部可以是端盖22。在另一些示例中，壁部可以是壳体21的一部分，例如，壁部既可以是壳体21的侧壁，也可以是壳体21的底壁。
为了描述简洁，附图和下面的描述均以端盖22为壁部进行说明。应理解，本申请描述的壁部并不局限于端盖22。
连接部24为环状结构且连接于主体部23和加强部25之间。连接部24的内端连接于加强部25，其外端连接于主体部23。
薄弱区241的强度小于主体部23的强度、加强部25的强度以及连接部24的其它区域的强度。示例性地，薄弱区241的厚度小于主体部23的厚度、加强部25的厚度以及连接部24的其它区域的厚度。本申请实施例可通过在连接部24上开设凹槽、刻痕等结构来减小薄弱区241的厚度和强度，以使薄弱区241能够在电池单体7的内部压力达到阈值时破裂。
加强部25的厚度是指加强部25在壁部的厚度方向Z上的尺寸，主体部23的厚度是指主体部23在壁部的厚度方向Z上的尺寸。在本申请实施例的描述中，厚度是指实体部分沿厚度方向Z的尺寸。
连接部24和加强部25组成电池单体7的泄压机构。示例性地，在薄弱区241破裂之后，加强部25可以在内部压力的作用下完全脱离主体部23，也可以与主体部23保持连接并向外翻折。
在电池单体7出现热失控时，壁部在内部压力的作用下变形。在本实施例中，主体部23相对于加强部25的具有较小的厚度，所以在内部压力的作用下，主体部23相对于加强部25更容易发生变形。主体部23变形时应力传递到连接部24上，而由于 加强部25的厚度较大且不易变形，所以加强部25难以通过变形来释放连接部24上的应力，这样，薄弱区241要同时承受该应力和内部压力的作用，其更容易破裂。因此，相对于传统的泄压机构，本实施例能够在不改变薄弱区241破裂所需的内部压力的前提下，增大薄弱区241的厚度，从而降低薄弱区241在正常使用过程中破裂的风险，延长电池单体7的使用寿命，提高电池单体7的安全性。
相对于传统的泄压机构，本实施例能够增大薄弱区241的厚度，这样简化薄弱区241的成型工艺，改善其在成型过程中厚度的均一性，保证薄弱区241的不同部分破裂所需的内部压力的一致性。
在一些实施例中，壁部包括第一凹部26，第一凹部26从壁部背离电极组件10的一侧沿面向电极组件10的方向凹陷。加强部25包括凸出于第一凹部26的底面的第一凸部251，第一凸部251的至少部分容纳于第一凹部26内。连接部24形成于与第一凹部26的底面相对应的区域。
第一凹部26在背离电极组件10的一端开口。
在一些示例中，第一凸部251可以整体容纳于第一凹部26内。在另一些示例中，第一凸部251也可以凸出到第一凹部26外，第一凸部251仅部分容纳于第一凹部26内。
第一凹部26的底面的至少部分为连接部24的背离电极组件10的表面。
本实施例通过在壁部上开设第一凹部26来减小连接部24的厚度，进而减小薄弱区241的强度，以使薄弱区241能够在电池单体7的内部压力达到阈值时破裂。
在一些实施例中，第一凹部26可通过挤压壁部形成。在挤压成型的过程中，壁部的一部分材料流动到加强部25，以增大加强部25的厚度和强度。
在一些实施例中，第一凹部26的底面为垂直于厚度方向Z的平面。
在一些实施例中，第一凸部251整体容纳于第一凹部26内。
在本实施例中，第一凹部26可以完全容纳第一凸部251，这样可以避免第一凸部251增大外壳20在厚度方向Z上的最大尺寸，提高电池单体7的能量密度。
在一些实施例中，在厚度方向Z上，第一凹部26的深度等于第一凸部251凸出第一凹部26的底面的尺寸。
在一些实施例中，壁部还包括第二凹部27，第二凹部27从壁部面向电极组件10的一侧沿背离电极组件10的方向凹陷。连接部24形成于第一凹部26的底面和第二 凹部27的底面之间。加强部25还包括凸出于第二凹部27的底面的第二凸部252，第二凸部252的至少部分容纳于第二凹部27内。
第二凹部27在面向电极组件10的一端开口。
在一些示例中，第二凸部252可以整体容纳于第二凹部27内。在另一些示例中，第二凸部252也可以凸出到第二凹部27外，第二凸部252仅部分容纳于第二凹部27内。
在连接部24的厚度一定时，如果仅在连接部24的一侧设置第一凹部26，那么第一凹部26的深度较大，第一凹部26成型的难度较大。本实施例通过开设第一凹部26和第二凹部27来形成连接部24，这样可以减小第一凹部26和第二凹部27对深度的要求，降低成型难度。本实施例通过设置第二凸部252可以进一步增大加强部25的厚度。
在一些实施例中，第二凹部27通过挤压壁部形成。在挤压成型的过程中，壁部的一部分材料流动到加强部25，以增大加强部25的厚度和强度。
在一些实施例中，主体部23包括本体部231，本体部231包括相对设置的内表面231a和外表面231b，内表面231a面向电极组件10，第一凹部26从外表面231b沿面向电极组件10的方向凹陷。第二凸部252凸出于内表面231a。
内表面231a和外表面231b沿厚度方向Z相对设置，内表面231a面向电极组件10而外表面231b背离电极组件10。示例性地，内表面231a和外表面231b均为垂直于厚度方向Z的平面，内表面231a和外表面231b的间距为本体部231的厚度。
本实施例的第二凸部252凸出于内表面231a，以使加强部25的最大厚度大于本体部231的最大厚度。
在一些实施例中，第一凸部251不凸出外表面231b；示例性地，外表面231b和第一凸部251的顶端面齐平。
在一些实施例中，主体部23还包括凸出于内表面231a的第三凸部232，第二凹部27从第三凸部232的顶端面沿背离电极组件10的方向凹陷，且第三凸部232环绕在第二凹部27的外侧。
在本实施例中，第三凸部232既可以在壁部的形成第二凹部27的位置起到加强作用，还可增大第二凹部27凹陷的深度，为加强部25提供更多的材料。
在一些实施例中，第二凸部252整体容纳于第二凹部27内。
在本实施例中，第二凹部27可以完全容纳第二凸部252，这样可以降低第二凸部252与电池单体7内部的其它结构干涉的风险。
在一些实施例中，第二凸部252的顶端面和第三凸部232的顶端面齐平。
示例性地，第二凸部252的顶端面和第三凸部232的顶端面均为垂直于厚度方向Z的平面。
本实施例能够在不增大壁部沿厚度方向Z的最大尺寸的前提下，尽可能地增大加强部25的厚度。
在一些实施例中，在壁部的厚度方向Z上，第二凹部27的底面比内表面231a更靠近电极组件10。
在连接部24的厚度一定的前提下，第二凹部27的底面越靠近电极组件10，第一凹部26的底面也就越靠近电极组件10。本实施例使第二凹部27的底面比内表面231a更靠近电极组件10，以增大第一凹部26的底面和外表面231b的距离，减小连接部24的薄弱区241被外部构件损伤的风险，提高电池单体7的安全性和使用寿命。
在一些实施例中，加强部25设有第三凹部253，第三凹部253从第二凸部252的顶端面沿背离电极组件10的方向延伸。在壁部的厚度方向Z上，第三凹部253的底面和第一凸部251的顶端面之间的距离大于主体部23的最大厚度。
示例性地，第三凹部253的底面和第一凸部251的顶端面平行设置。
在本实施例中，通过开设第三凹部253可以增大电池单体7的内部空间，以使外壳20内部能够容纳更多的电解液，改善电池单体7的性能。加强部25的位于第三凹部253的底面和第一凸部251的顶端面之间的部分的厚度大于主体部23的最大厚度，以保证加强部25的强度满足要求。
在一些实施例中，第三凹部253可通过挤压加强部25形成。在挤压成型的过程中，加强部25的一部分材料向第三凹部253周围的部分移动、聚集，以增大加强部25局部的最大厚度和强度。
在一些实施例中，在壁部的厚度方向Z上，第三凹部253的深度小于第二凸部252凸出于第二凹部27的底面的尺寸。
本实施例通过控制第三凹部253的深度，以使加强部25的位于第三凹部253的底面和第一凸部251的顶端面之间的部分的厚度大于主体部23的最大厚度，保证加强部25的强度满足要求。
在一些实施例中，连接部24设有凹槽242，以在与凹槽242相对应的区域形成薄弱区241。
凹槽242可以设置于连接部24的面向电极组件10的表面，也可以设置于连接部24的背离电极组件10的表面。沿壁部的厚度方向Z，薄弱区241和凹槽242对应设置。
示例性地，可以采用机加工方式在连接部24上去除材料以形成凹槽242，有利于降低加工成本和加工难度。可替代地，凹槽242也可通过挤压连接部24的方式形成。
本实施例通过在连接部24上开设凹槽242，以在连接部24上形成薄弱区241，使薄弱区241的强度小于连接部24的其它区域的强度。
在一些实施例中，壁部还包括弯折部28和板体部29。弯折部28环绕在主体部23的外侧并沿面向电极组件10的方向延伸，以在主体部23的面向电极组件10的一侧形成第四凹部29a。板体部29环绕在弯折部28的外侧，第四凹部29a相对于板体部29的面向电极组件10的表面凹陷。
示例性地，壁部为端盖22，板体部29用于连接到壳体21。
本实施例通过设置第四凹部29a，可以增大电池单体7的内部空间，提高电池单体7的容量。同时，第四凹部29a还能够为加强部25提供空间，使加强部25具有足够的厚度。
在一些实施例中，加强部25的最大厚度大于板体部29的最大厚度和弯折部28的最大厚度。
在一些实施例中，外壳20包括壳体21和端盖22，壳体21具有开口，端盖22用于盖合于壳体21的开口。端盖22为壁部。
相对于壳体21，端盖22上更容易形成加强部25和连接部24等结构。
在一些实施例中，端盖22为一体形成结构。
本实施例将具有泄压功能的连接部24和加强部25集成在端盖22上，以简化电池单体7的结构。
图8为本申请另一些实施例提供的电池单体的端盖的局部剖视图。
如图8所示，在一些实施例中，加强部25凸出于主体部23面向电极组件10的表面。本实施例使加强部25面向电极组件10凸出，以增大加强部25的厚度和强度。
在一些实施例中，主体部23的面向电极组件10的表面和连接部24的面向电极 组件10的表面齐平。
图9为本申请一些实施例提供的电池单体的制造方法的流程示意图。
如图9所示，本申请实施例的电池单体的制造方法包括：
S100、提供电极组件；
S200、提供外壳，外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧；
S300、将电极组件安装到外壳内；
其中，连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力；加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。
需要说明的是，通过上述电池单体的制造方法制造出的电池单体的相关结构，可参见上述各实施例提供的电池单体。
在基于上述的电池单体的制造方法制造电池单体时，不必按照上述步骤依次进行，也就是说，可以按照实施例中提及的顺序执行步骤，也可以不同于实施例中提及的顺序执行步骤，或者若干步骤同时执行。例如，步骤S100、S200的执行不分先后，也可以同时进行。
图10为本申请一些实施例提供的电池单体的制造系统的示意性框图。
如图10所示，本申请实施例的电池单体的制造系统90包括第一提供装置91、第二提供装置92和组装装置93。第一提供装置91用于提供电极组件；第二提供装置92用于提供外壳，外壳包括壁部，壁部包括主体部、连接部和加强部，连接部环绕在加强部的外侧，主体部环绕在连接部的外侧；组装装置93用于将电极组件安装到外壳内。连接部设置有薄弱区，电池单体被配置为在电池单体的内部压力达到阈值时沿薄弱区破裂，以泄放内部压力；加强部的最大厚度大于主体部的最大厚度，以减小加强部在内部压力的作用下的变形。
通过上述制造系统制造出的电池单体的相关结构，可参见上述各实施例提供的电池单体。
需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。
最后应说明的是：以上实施例仅用以说明本申请的技术方案，而非对其限制； 尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换，但这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的精神和范围。

Claims (20)

  1. 一种电池单体，包括外壳和容纳于所述外壳内的电极组件；
    所述外壳包括壁部，所述壁部包括主体部、连接部和加强部，所述连接部环绕在所述加强部的外侧，所述主体部环绕在所述连接部的外侧；
    所述连接部设置有薄弱区，所述电池单体被配置为在所述电池单体的内部压力达到阈值时沿所述薄弱区破裂，以泄放所述内部压力；
    所述加强部的最大厚度大于主体部的最大厚度，以减小所述加强部在所述内部压力的作用下的变形。
  2. 根据权利要求1所述的电池单体，其中，所述壁部包括第一凹部，所述第一凹部从所述壁部背离所述电极组件的一侧沿面向所述电极组件的方向凹陷；
    所述加强部包括凸出于所述第一凹部的底面的第一凸部，所述第一凸部的至少部分容纳于所述第一凹部内；
    所述连接部形成于与所述第一凹部的底面相对应的区域。
  3. 根据权利要求2所述的电池单体，其中，所述第一凸部整体容纳于所述第一凹部内。
  4. 根据权利要求2或3所述的电池单体，其中，所述加强部凸出于所述主体部面向所述电极组件的表面。
  5. 根据权利要求2或3所述的电池单体，其中，所述壁部还包括第二凹部，所述第二凹部从所述壁部面向所述电极组件的一侧沿背离所述电极组件的方向凹陷；
    所述连接部形成于所述第一凹部的底面和所述第二凹部的底面之间；
    所述加强部还包括凸出于所述第二凹部的底面的第二凸部，所述第二凸部的至少部分容纳于所述第二凹部内。
  6. 根据权利要求5所述的电池单体，其中，所述主体部包括本体部，所述本体部包括相对设置的内表面和外表面，所述内表面面向所述电极组件，所述第一凹部从所述外表面沿面向所述电极组件的方向凹陷；
    所述第二凸部凸出于所述内表面。
  7. 根据权利要求6所述的电池单体，其中，所述主体部还包括凸出于所述内表面的第三凸部，所述第二凹部从所述第三凸部的顶端面沿背离所述电极组件的方向凹陷， 且所述第三凸部环绕在所述第二凹部的外侧。
  8. 根据权利要求7所述的电池单体，其中，所述第二凸部整体容纳于所述第二凹部内。
  9. 根据权利要求8所述的电池单体，其中，所述第二凸部的顶端面和所述第三凸部的顶端面齐平。
  10. 根据权利要求7-9任一项所述的电池单体，其中，在所述壁部的厚度方向上，所述第二凹部的底面比所述内表面更靠近所述电极组件。
  11. 根据权利要求5-10任一项所述的电池单体，其中，所述加强部设有第三凹部，所述第三凹部从所述第二凸部的顶端面沿背离所述电极组件的方向延伸；
    在所述壁部的厚度方向上，所述第三凹部的底面和所述第一凸部的顶端面之间的距离大于所述主体部的最大厚度。
  12. 根据权利要求11所述的电池单体，其中，在所述壁部的厚度方向上，所述第三凹部的深度小于所述第二凸部凸出于所述第二凹部的底面的尺寸。
  13. 根据权利要求1-12任一项所述的电池单体，其中，所述连接部设有凹槽，以在与所述凹槽相对应的区域形成所述薄弱区。
  14. 根据权利要求1-13任一项所述的电池单体，其中，所述壁部还包括：
    弯折部,环绕在所述主体部的外侧并沿面向所述电极组件的方向延伸，以在所述主体部的面向所述电极组件的一侧形成第四凹部；以及
    板体部，环绕在所述弯折部的外侧，所述第四凹部相对于所述板体部的面向所述电极组件的表面凹陷。
  15. 根据权利要求1-14任一项所述的电池单体，其中，所述外壳包括壳体和端盖，所述壳体具有开口，所述端盖用于盖合于所述壳体的开口；
    所述端盖为所述壁部。
  16. 根据权利要求15所述的电池单体，其中，所述端盖为一体形成结构。
  17. 一种电池，包括多个根据权利要求1-16中任一项所述的电池单体。
  18. 一种用电装置，包括根据权利要求1-16中任一项所述的电池单体，所述电池单体用于提供电能。
  19. 一种电池单体的制造方法，包括：
    提供电极组件；
    提供外壳，所述外壳包括壁部，所述壁部包括主体部、连接部和加强部，所述连接部环绕在所述加强部的外侧，所述主体部环绕在所述连接部的外侧；
    将所述电极组件安装到所述外壳内；
    其中，所述连接部设置有薄弱区，所述电池单体被配置为在所述电池单体的内部压力达到阈值时沿所述薄弱区破裂，以泄放所述内部压力；所述加强部的最大厚度大于主体部的最大厚度，以减小所述加强部在所述内部压力的作用下的变形。
  20. 一种电池单体的制造系统，包括：
    第一提供装置，用于提供电极组件；
    第二提供装置，用于提供外壳，所述外壳包括壁部，所述壁部包括主体部、连接部和加强部，所述连接部环绕在所述加强部的外侧，所述主体部环绕在所述连接部的外侧；
    组装装置，用于将所述电极组件安装到所述外壳内；
    其中，所述连接部设置有薄弱区，所述电池单体被配置为在所述电池单体的内部压力达到阈值时沿所述薄弱区破裂，以泄放所述内部压力；所述加强部的最大厚度大于主体部的最大厚度，以减小所述加强部在所述内部压力的作用下的变形。
PCT/CN2021/134485 2021-11-30 2021-11-30 电池单体及其制造方法和制造系统、电池以及用电装置 Ceased WO2023097469A1 (zh)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CN202180089712.3A CN116711142A (zh) 2021-11-30 2021-11-30 电池单体及其制造方法和制造系统、电池以及用电装置
EP21965910.9A EP4432444A4 (en) 2021-11-30 2021-11-30 Battery cell and manufacturing method and manufacturing system therefor, battery and electrical device
PCT/CN2021/134485 WO2023097469A1 (zh) 2021-11-30 2021-11-30 电池单体及其制造方法和制造系统、电池以及用电装置
US18/669,179 US20240313338A1 (en) 2021-11-30 2024-05-20 Battery cell, method and system for manufacture same, battery, and power consuming device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2021/134485 WO2023097469A1 (zh) 2021-11-30 2021-11-30 电池单体及其制造方法和制造系统、电池以及用电装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/669,179 Continuation US20240313338A1 (en) 2021-11-30 2024-05-20 Battery cell, method and system for manufacture same, battery, and power consuming device

Publications (1)

Publication Number Publication Date
WO2023097469A1 true WO2023097469A1 (zh) 2023-06-08

Family

ID=86611350

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/134485 Ceased WO2023097469A1 (zh) 2021-11-30 2021-11-30 电池单体及其制造方法和制造系统、电池以及用电装置

Country Status (4)

Country Link
US (1) US20240313338A1 (zh)
EP (1) EP4432444A4 (zh)
CN (1) CN116711142A (zh)
WO (1) WO2023097469A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025010831A1 (zh) * 2023-07-13 2025-01-16 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备
WO2025015680A1 (zh) * 2023-07-18 2025-01-23 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备
WO2025091671A1 (zh) * 2023-11-03 2025-05-08 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN221994648U (zh) * 2023-10-20 2024-11-12 宁德时代新能源科技股份有限公司 电池单体、电池及用电装置
WO2025107153A1 (zh) * 2023-11-21 2025-05-30 宁德时代新能源科技股份有限公司 电池单体、电池以及用电装置

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016051656A (ja) * 2014-09-01 2016-04-11 株式会社豊田自動織機 蓄電装置
CN205582984U (zh) * 2016-05-12 2016-09-14 宁德时代新能源科技股份有限公司 二次电池顶盖
CN207542310U (zh) * 2017-12-14 2018-06-26 江苏塔菲尔新能源科技股份有限公司 一种动力电池顶盖防爆结构
CN108461665A (zh) * 2018-05-31 2018-08-28 东莞百思利新能源科技有限公司 二次电池顶盖及其二次电池
CN208460852U (zh) * 2018-03-30 2019-02-01 宁德时代新能源科技股份有限公司 防爆膜及二次电池顶盖
CN110797478A (zh) * 2018-08-01 2020-02-14 宁德时代新能源科技股份有限公司 二次电池
CN212136565U (zh) * 2020-06-24 2020-12-11 中航锂电（洛阳）有限公司 防爆膜、动力电池盖板结构及电池
CN212277340U (zh) * 2020-07-10 2021-01-01 荣盛盟固利新能源科技有限公司 防爆阀、动力电池盖板及动力电池
CN213026310U (zh) * 2020-07-10 2021-04-20 宁德时代新能源科技股份有限公司 电池盒、电池单体、电池和用电设备

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101323036B1 (ko) * 2009-05-25 2013-10-29 도요타지도샤가부시키가이샤 전지 팩, 그 전지 팩을 탑재한 차량 및 기기
JP6963964B2 (ja) * 2017-01-27 2021-11-10 株式会社Ｇｓユアサ 破裂弁および蓄電素子
JP7225110B2 (ja) * 2017-10-23 2023-02-20 三洋電機株式会社 円筒形電池
JP7792615B2 (ja) * 2021-03-18 2025-12-26 パナソニックＩｐマネジメント株式会社 封口板およびそれを用いた蓄電装置

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016051656A (ja) * 2014-09-01 2016-04-11 株式会社豊田自動織機 蓄電装置
CN205582984U (zh) * 2016-05-12 2016-09-14 宁德时代新能源科技股份有限公司 二次电池顶盖
CN207542310U (zh) * 2017-12-14 2018-06-26 江苏塔菲尔新能源科技股份有限公司 一种动力电池顶盖防爆结构
CN208460852U (zh) * 2018-03-30 2019-02-01 宁德时代新能源科技股份有限公司 防爆膜及二次电池顶盖
CN108461665A (zh) * 2018-05-31 2018-08-28 东莞百思利新能源科技有限公司 二次电池顶盖及其二次电池
CN110797478A (zh) * 2018-08-01 2020-02-14 宁德时代新能源科技股份有限公司 二次电池
CN212136565U (zh) * 2020-06-24 2020-12-11 中航锂电（洛阳）有限公司 防爆膜、动力电池盖板结构及电池
CN212277340U (zh) * 2020-07-10 2021-01-01 荣盛盟固利新能源科技有限公司 防爆阀、动力电池盖板及动力电池
CN213026310U (zh) * 2020-07-10 2021-04-20 宁德时代新能源科技股份有限公司 电池盒、电池单体、电池和用电设备

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4432444A4 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025010831A1 (zh) * 2023-07-13 2025-01-16 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备
WO2025015680A1 (zh) * 2023-07-18 2025-01-23 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备
WO2025091671A1 (zh) * 2023-11-03 2025-05-08 宁德时代新能源科技股份有限公司 电池单体、电池及用电设备

Also Published As

Publication number Publication date
EP4432444A1 (en) 2024-09-18
US20240313338A1 (en) 2024-09-19
EP4432444A4 (en) 2025-06-18
CN116711142A (zh) 2023-09-05

Similar Documents

Publication Publication Date Title
CN216354620U (zh) 电池单体、电池以及用电装置
CN216354617U (zh) 电池单体、电池以及用电装置
CN116325329B (zh) 电池单体及其制造方法和制造系统、电池以及用电装置
US20240079693A1 (en) End cover assembly, battery cell, battery, and electrical apparatus
CN216085200U (zh) 电池单体、电池以及用电装置
CN216213727U (zh) 电池单体、电池以及用电装置
US20240097298A1 (en) Box of battery, battery, power consumption device, and method and apparatus for producing box
US20230261312A1 (en) End cover assembly, battery cell, battery, and electrical apparatus
CN116438702A (zh) 泄压装置、电池单体、电池及用电设备
CN217788606U (zh) 电池单体、电池及用电设备
WO2023056719A1 (zh) 端盖、电池单体、电池以及用电装置
US20240372207A1 (en) Box of battery, battery, power consumption apparatus, and method and apparatus for producing battery
WO2023097469A1 (zh) 电池单体及其制造方法和制造系统、电池以及用电装置
WO2022252010A1 (zh) 电池单体及其制造方法和制造系统、电池以及用电装置
CN116529941A (zh) 电池单体及其制造方法和制造系统、电池以及用电装置
EP4145612B1 (en) Battery cell and manufacturing method and manufacturing system therefor, battery, and electrical device
WO2023050278A1 (zh) 电池单体及其制造方法和制造系统、电池以及用电装置
CN117941134A (zh) 电池单体的端盖组件、电池单体、电池以及用电装置
WO2023133855A1 (zh) 电池、用电设备及电池的制备方法和制备装置
CN217158410U (zh) 电池单体、电池以及用电装置
WO2023245430A1 (zh) 电池单体、电池及用电设备
WO2023141902A1 (zh) 端盖组件、电池单体、电池以及用电装置
WO2023141842A1 (zh) 泄压装置、电池单体、电池及用电设备
CN219553748U (zh) 电池单体、电池以及用电装置
US20250337096A1 (en) Battery cell, battery, and electric apparatus

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 202180089712.3

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21965910

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2021965910

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2021965910

Country of ref document: EP

Effective date: 20240614

NENP Non-entry into the national phase

Ref country code: DE