JPH07176331A - Organic electrolyte secondary battery and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Object] To provide an organic electrolyte secondary battery that is safe, has a long cycle life, and is inexpensive, and a method for manufacturing the same. A positive electrode plate 2 in a discharged state is formed by a positive electrode active material made of lead dioxide in which lithium ions are intercalated, and a negative electrode plate 3 in a discharged state is formed by a negative electrode active material made of graphite. An organic electrolyte secondary battery is assembled in a discharged state using the positive electrode plate 2 and the negative electrode plate 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electrolyte secondary battery, and more particularly to a lithium ion battery and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, various organic electrolyte secondary batteries using metallic lithium as a negative electrode active material have been developed. For example, Electrochimica Acta, Vol.22, pp.1141-114
5 discloses a lithium secondary battery using a lead compound as a positive electrode active material and metallic lithium as a negative electrode active material. Also, Journal of Power Sources 45 (199
3), pp.209-217 discloses a lithium secondary battery using lead dioxide as a positive electrode active material and metallic lithium as a negative electrode active material. In this lithium secondary battery,
Plate-shaped stainless steel is used as the positive electrode current collector.

Since lithium metal has the lowest density and the highest electrode potential among solid elements, the lithium secondary battery has the advantage of high battery voltage and energy density.

[0004]

However, in a lithium secondary battery using lithium metal as a negative electrode active material, dendrite of lithium is deposited during charging, which may cause an internal short circuit. Therefore, there is a problem in terms of safety, and there is a drawback that the life is short at about 150 cycles. Further, since expensive metallic lithium is used as the negative electrode active material, there is a problem that the material cost becomes high and the battery becomes expensive. Further, the stainless steel of the positive electrode current collector is also relatively expensive.

Recently, a lithium ion battery using a LiCo compound as a positive electrode active material and a carbon material as a negative electrode active material has been proposed. In this lithium-ion battery, LiCoO ₂ or LiCo is used as the positive electrode active material.
_1-x Sn _x O ₂ is used. In such a lithium-ion battery, since lithium dendrites do not deposit during charging, an internal short circuit does not occur and the cycle life is long. Further, this lithium-ion battery has the advantages that the volume energy density and the weight energy density are very high and the output voltage is also high.

However, LiCo is used as the positive electrode active material.
In a lithium-ion battery that uses a system-based compound, the raw material lithium carbonate and cobalt oxide are rare metals with few reserves worldwide, so the supply of materials becomes unstable,
There is a problem that the material cost is also high. In particular, when forming a large secondary battery used in an electric vehicle or the like, the problem of material cost becomes serious.

Therefore, an object of the present invention is to provide an organic electrolyte secondary battery which is safe, has a long cycle life, and can be manufactured at a low cost, and a manufacturing method thereof.

[0008]

The organic electrolyte secondary battery according to the first invention comprises a positive electrode active material made of a lead compound in which lithium ions are intercalated and a negative electrode active material made of a carbon material. .

The organic electrolyte secondary battery according to the second invention is
A positive electrode active material consisting of a lead compound in which lithium ions are intercalated in a discharged state, a lead compound in a charged state, and a carbon material in a discharged state, and a lithium ion intercalated carbon material in a charged state. And a negative electrode active material.

The organic electrolyte secondary battery according to the third invention is
A positive electrode active material made of a lead compound in which lithium ions are intercalated, a negative electrode active material made of a carbon material, and a positive electrode current collector made of lead or a lead alloy attached to the positive electrode active material are provided.

The organic electrolyte secondary battery according to the fourth invention is
In the organic electrolyte secondary battery according to the first aspect of the present invention, the lead compound is lead dioxide.

In the method for manufacturing an organic electrolyte secondary battery according to the fifth aspect of the invention, a positive electrode active material in a discharged state is formed by intercalating lithium ions into a lead compound, and a negative electrode active material in a discharged state is formed by a carbon material. A material is formed and a battery is assembled in a discharged state using the positive electrode active material and the negative electrode active material.

In the method of manufacturing an organic electrolyte secondary battery according to the sixth aspect of the invention, a positive electrode active material in a discharged state is formed by intercalating lithium ions in a lead compound, and a negative electrode active material in a discharged state is formed by a carbon material. A material is formed, a positive electrode current collector made of lead or a lead alloy is attached to the positive electrode active material, and a battery is assembled in a discharged state using the positive electrode active material and the negative electrode active material.

[0014]

In the organic electrolyte secondary batteries according to the first to fourth aspects of the invention, the positive electrode active material is made of a lead compound in which lithium ions are intercalated in a discharged state, and the negative electrode active material is made of a carbon material. When this secondary battery is charged, lithium ions are deintercalated from the lead compound of the positive electrode active material, and lithium ions are intercalated into the carbon material of the negative electrode active material. On the contrary, when this secondary battery is discharged, lithium ions are deintercalated from the carbon material of the negative electrode active material, and lithium ions are intercalated into the lead compound of the positive electrode active material.

In this organic electrolyte secondary battery, since lithium dendride does not deposit during charging, an internal short circuit does not occur and the life is long at about 2000 cycles. Also,
Since a cheap lead compound is used as the positive electrode active material and a cheap and long-life carbon material is used as the negative electrode active material, the material cost is low.

Particularly, in the organic electrolyte secondary battery according to the third aspect of the present invention, since the positive electrode current collector made of inexpensive lead or lead alloy is used, the material cost is further reduced.

In the method for manufacturing an organic electrolyte secondary battery according to the fifth and sixth aspects of the invention, a positive electrode active material in a discharged state made of a lead compound in which lithium ions are intercalated and a negative electrode in a discharged state made of a carbon material are used. A battery is assembled using the active material. A carbon material in which lithium ions are intercalated is unstable in the air, whereas a lead compound in which lithium ions are intercalated is stable in the air. In the manufacturing method according to the fifth and sixth aspects of the invention, it is not necessary to use an unstable material, and therefore the manufacturing process becomes easy. Moreover, since the positive electrode active material is made of an inexpensive lead compound and the negative electrode active material is made of a carbon material which is inexpensive and has a long life, the manufacturing cost is reduced.

Particularly, in the method for manufacturing an organic electrolyte secondary battery according to the sixth aspect of the invention, the positive electrode current collector is made of inexpensive lead or lead alloy, so that the manufacturing cost is further reduced.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view of organic electrolyte secondary batteries applied to the first to fourth examples described below.

In FIG. 1, positive electrode plates 2 and negative electrode plates 3 are alternately arranged in a battery case 1 made of stainless steel with a separator 4 made of polypropylene interposed therebetween. Battery case 1
The insulating plate 5 is inserted on the side surface and the bottom surface inside the.
A positive electrode terminal 7 and a negative electrode terminal 8 are attached to the battery cover 6. The positive electrode terminal 7 and the negative electrode terminal 8 are insulated from the battery cover 6 by the insulating material 9. The positive electrode plate 2 is connected to the positive electrode terminal 7, and the negative electrode plate 3 is connected to the negative electrode terminal 8. A battery cover 6 is attached to the top of the battery case 1. Lithium perchlorate LiClO 2 as an organic electrolyte through an inlet 10 provided at the center of the battery cover 6.
Inject propylene carbonate in which ₄ is dissolved. This lithium ion battery is assembled in a discharged state.

A lead compound in which lithium ions are intercalated is used as the positive electrode active material. Lead compounds capable of intercalating lithium ions include lead oxides PbO ₂ , PbO, Pb ₃ O ₄ and lead fluoride PbF.
₃ , PbF ₂ , complex oxide PbCrO ₄ of lead and chromium
and so on.

As a method for intercalating lithium ions into lead oxide, there is a method in which lithium carbonate and lead carbonate are weighed in suitable proportions, well mixed and heat treated. Further, as a method of intercalating lithium ions into a lead compound, there is also a method in which n-butyllithium dissolved in hexane and the lead compound are put in a closed container for a long period of time, for example, 14 days, and stirred.

In addition to the above lead compounds, Pb
₄ O ₅ , Pb ₅ O ₆ , Pb ₅ O ₇ , Pb ₅ O ₈ , Pb ₂
It is also possible to intercalate lithium ions into lead oxide such as O ₃ .

(1) First Example In the first example, lead oxide in which lithium ions are intercalated is used as the positive electrode active material. Here, for example, lead dioxide Li _x PbO ₂ (0.5 ≦ x ≦ 4) in which lithium ions are intercalated is used. Further, powder graphite C is used as the negative electrode active material.

[0025] those of lithium ion was added and mixed intercalation dioxide lead Li _x PbO ₂ in a suitable binder and coated on a positive electrode current collector made of nickel, to form a positive electrode plate 2 discharged state. Further, a mixture of powder graphite and a binder is mixed and applied to a negative electrode current collector made of copper to form a negative electrode plate 3 in a discharged state. The positive electrode plate 2 and the negative electrode plate 3 in the discharged state are used to assemble the organic electrolyte secondary battery shown in FIG.

The charge / discharge reaction formula of the organic electrolyte secondary battery of this example is shown in Chemical formula 1.

[Chemical 1] As shown in Chemical formula 1, when this secondary battery is charged, lithium ions are deintercalated from lead dioxide PbO ₂ and intercalated into graphite.
On the contrary, when this secondary battery is discharged, lithium ions are deintercalated from graphite and intercalated into lead dioxide PbO ₂ .

Other lead oxides Li _y PbO, Li intercalated with lithium ions are used as the positive electrode active material.
may be used _z Pb ₃ O _4. The charge / discharge reaction formulas in this case are shown in Chemical formulas 2 and 3.

[Chemical 2]

[Chemical 3]

In the charge / discharge reaction formulas of Chemical formulas 2 and 3, during the charging, lithium ions are converted into lead oxides PbO and Pb.
It is deintercalated from ₃ O ₄ and intercalated into graphite. During discharge, lithium ions are deintercalated from graphite and intercalated into lead oxides PbO and Pb ₃ O ₄ .

(2) Second Example In the second example, lead fluoride obtained by intercalating lithium ions is used as the positive electrode active material. Here, for example, lead trifluoride Li _u PbF _{3 in} which lithium ions are intercalated is used. Further, powder graphite is used as the negative electrode active material.

Also in this embodiment, similarly to the first embodiment, the positive electrode plate 2 in the discharged state and the negative electrode plate 3 in the discharged state are formed, and the positive electrode plate 2 and the negative electrode plate 3 in the discharged state are used. The organic electrolyte secondary battery shown in FIG. 1 is assembled.

The charge / discharge reaction formula of the organic electrolyte secondary battery of this example is shown in Chemical formula 4.

[Chemical 4]

As shown in Chemical formula 4, when this secondary battery is charged, lithium ions are deintercalated from lead trifluoride PbF ₃ and intercalated into graphite. On the contrary, when this secondary battery is discharged, lithium ions are deintercalated from graphite and intercalated into lead trifluoride PbF ₃ .

As the positive electrode active material, other lead difluoride Li _v PbF ₂ intercalated with lithium ions may be used. The charge / discharge reaction formula in this case is shown in Chemical formula 5.

[Chemical 5]

In the charge-discharge reaction formula of Chemical formula 5, during charging, lithium ions are deintercalated from lead difluoride PbF ₂ and intercalated into graphite. During discharge, lithium ions are deintercalated from graphite and lead difluoride PbF
Intercalated to ₂ .

(3) Third Example In the third example, a composite oxide L of lead and chromium in which lithium ions were intercalated as a positive electrode active material was used.
i _w PbCrO ₄ is used. Further, powder graphite is used as the negative electrode active material.

Also in this embodiment, similarly to the first embodiment, the positive electrode plate 2 in the discharged state and the negative electrode plate 3 in the discharged state are formed, and the positive electrode plate 2 and the negative electrode plate 3 in the discharged state are used. The organic electrolyte secondary battery shown in FIG. 1 is assembled.

The charge / discharge reaction formula of the organic electrolyte secondary battery of this example is shown in Chemical formula 6.

[Chemical 6]

As shown in Chemical formula 6, when this secondary battery is charged, lithium ions are converted into a complex oxide Pb of lead and chromium, Pb.
It is deintercalated from CrO ₄ and intercalated into graphite. On the contrary, when this secondary battery is discharged, lithium ions are deintercalated from the graphite, and the composite oxide P of lead and chromium P
Intercalated into bCrO ₄ .

In the above Chemical Formulas 1 to 6, x, y, z,
The values of u, v, and w vary depending on the type of lead compound and the charging conditions.

In the first to third embodiments, since the inexpensive lead compound is used as the positive electrode active material and the inexpensive and long-life graphite is used as the negative electrode active material, the inexpensive and long-life organic electrolyte secondary solution is used. A battery is obtained.

As the positive electrode active material, another lead oxide Pb in which lithium ions are intercalated is used.
₄ O ₅ , Pb ₅ O ₆ , Pb ₅ O ₇ , Pb ₅ O ₈ , Pb ₂
O ₃ or the like may be used. Further, other carbon materials such as carbon fiber and acetylene black may be used as the negative electrode active material.

(4) Fourth Example In the fourth example, lead dioxide Li _x PbO ₂ intercalated with lithium ions is used as the positive electrode active material. Further, powder graphite is used as the negative electrode active material. Further, a lead grid formed by casting lead or a lead alloy is used as the positive electrode current collector. The configuration of the other parts is similar to that of the first embodiment. The charge / discharge reaction formula of this organic electrolyte secondary battery is similar to the reaction formula shown in Chemical formula 1.

As the positive electrode current collector, an expanded grid or a lead plate or a lead alloy plate formed by cutting and pulling a lead plate or a lead alloy plate may be used.

In the fourth embodiment, since the positive electrode current collector is made of inexpensive lead or lead alloy, an even cheaper organic electrolyte secondary battery can be obtained.

As the positive electrode active material, lead oxide in which lithium ions are intercalated, lead fluoride, or a composite oxide of lead and chromium may be used as in the first to third embodiments. Further, other carbon materials such as carbon fiber and acetylene black may be used as the negative electrode active material.

Although the above-described embodiments are applied to large-sized secondary batteries used in, for example, electric vehicles, the present invention is not limited to large-sized secondary batteries, but is applicable to all types of organic electrolyte secondary batteries. It is possible.

[0047]

According to the first to sixth aspects of the invention, an inexpensive lead compound is used as the positive electrode active material and an inexpensive and long-life carbon material is used as the negative electrode active material. The next battery is obtained. Further, since dendrite of lithium does not deposit during charging, it is safe and has a long cycle life. Furthermore, since the battery can be assembled in a discharged state, the manufacturing process is simplified.

In particular, according to the third and fourth inventions, since inexpensive lead or lead alloy is used as the positive electrode current collector, an even cheaper organic electrolyte secondary battery can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an organic electrolyte secondary battery applied to an example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery case 2 Positive electrode plate 3 Negative electrode plate 4 Separator 5 Insulating plate 6 Battery cover 7 Positive electrode terminal 8 Negative electrode terminal 11 Organic electrolyte

Claims (6)

[Claims] 1. An organic electrolyte secondary battery comprising a positive electrode active material made of a lead compound in which lithium ions are intercalated and a negative electrode active material made of a carbon material. 2. A positive electrode active material composed of a lead compound in which lithium ions are intercalated in a discharged state, a lead compound in a charged state, and a carbon material in a discharged state, and lithium ions are intercalated in a charged state. Electrolyte secondary battery comprising a negative electrode active material made of the above-mentioned carbon material. 3. A positive electrode active material made of a lead compound in which lithium ions are intercalated, a negative electrode active material made of a carbon material, and a positive electrode current collector made of lead or a lead alloy attached to the positive electrode active material. An organic electrolyte secondary battery comprising. 4. The lead compound is lead dioxide.
The organic electrolyte secondary battery described. 5. A positive electrode active material in a discharged state is formed by intercalating lithium ions in a lead compound, and a negative electrode active material in a discharged state is formed by a carbon material, and the positive electrode active material and the negative electrode active material are A method of manufacturing an organic electrolyte secondary battery, which comprises using the secondary battery in a discharged state. 6. A positive electrode active material in a discharged state is formed by intercalating lithium ions in a lead compound, and a negative electrode active material in a discharged state is formed by a carbon material, and the positive electrode active material is made of lead or a lead alloy. A method of manufacturing an organic electrolyte secondary battery, comprising: mounting a positive electrode current collector of the above, and assembling a secondary battery in a discharged state using the positive electrode active material and the negative electrode active material.