JPH0789497B2 - Energy storage - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light energy storage device, and more particularly to an energy storage device having a portion for photoelectrically converting light energy and a portion for temporarily storing the obtained electric energy. It relates to a storage device.

2. Description of the Related Art Conventionally, when light energy such as sunlight is used as electric energy, two methods have been mainly used. That is, the first method is an element having a photoelectric conversion capability such as a solar cell, which converts light energy into electric energy and supplies the obtained electric energy directly to a load as a power source. The second method is an element having a photoelectric conversion capability, such as a solar cell, which converts light energy into electric energy and temporarily stores the obtained electric energy in an energy storage device such as a capacitor or a secondary battery. It is a method of supplying electric energy to a load.

Problems to be Solved by the Invention In the former method, since electric energy obtained by photoelectric conversion is immediately used, when the light source becomes weak or disappears, the electromotive force becomes weak in response to this. The voltage stability cannot be guaranteed at all, and the stability of voltage cannot be guaranteed at all, and further, it is completely unsuitable for strong discharge.
In the latter method, the problems like the former are overcome, and the voltage stability and the stability against strong discharge are obtained, but
A solar cell and a capacitor or a battery have to be connected together for use, the size of the device has become large, and the connection between the two has become a new complication.

The present invention overcomes the drawbacks of the conventional methods as described above, and is intended to obtain a small-sized energy storage device in which a photoelectric conversion unit and an energy storage unit are integrated, and is stable against strong discharge. The present invention provides an energy storage device that provides a fixed voltage output.

Means for Solving the Problems The energy storage device of the present invention comprises a metal plate carrying a so-called solar cell having a photovoltaic power on one surface as one current collector, and comprising a polarizable electrode, a separator, a counter electrode and an electrolyte solution. The energy storage unit is configured to have a flat plate shape.

Effect According to the present invention, the conductive substrate carrying a so-called solar cell having a photovoltaic function serves as one current collector, and a pair of polarizable electrodes or a non-separable part of the polarizable electrode is brought into contact with the current collector. Since the polar electrode is installed via the separator and the portion having photovoltaic power and the portion for storing electric energy are combined into an integral shape, a small and thin energy storage device can be obtained, and The stability of the output voltage against discharge is also excellent.

Here, the energy storage unit is sealed by the conductive base body, the conductive base body that constitutes the current collector of the other electrode, and the insulating sealing material interposed between the peripheral portions of both conductive base bodies. It is preferable that it is configured to be.

A polarizable electrode or a non-polarizable electrode is used as the counter electrode of the energy storage unit. The polarizable electrode is typically one using activated carbon. On the other hand, a lithium electrode is used as the non-polarizable electrode. This may be made of metallic lithium, but it is preferable to use a wood alloy or the like that reversibly occludes and releases lithium by charging and discharging.

Examples Hereinafter, specific examples of the present invention will be described in detail.

Example 1 As shown in FIG. 2, an insulating resin layer 2 is applied to one surface of a stainless steel plate 1 having a size of 15 mm × 50 mm and a thickness of 0.1 mm, followed by firing. As shown in the same figure, a plurality of electrodes 3, a continuous amorphous silicon layer 4, and a transparent electrode 5 are provided on the insulating resin layer 2 to form a solar cell 6 in which four cells are connected in series. Stainless steel substrate 1 having this solar cell
Using the back surface of the above as a collector, a polarizable electrode 8 having a conductive collector electrode 7, a separator 9, another polarizable electrode 11 having a conductive electrode 10, and a stainless steel plate collector 12 are combined. The polarizable electrodes 7 and 12 each have a size of 10 mm × 45 mm, and each is impregnated with an electrolytic solution in which tetraethylammonium perchlorate is dissolved in propylene carbonate.
First, the above-described components are provided together with the insulating sealing member 13.
Assemble in the configuration shown. The insulating sealing member 13 is a polypropylene film (thickness 0.8 mm), and is bonded to the two stainless steel plates 1 and 12 by heat fusion, so that the plates 1 and 12 and the insulating sealing member are
The space surrounded by 13 and is sealed. The conductive electrode
Reference numerals 7 and 10 denote aluminum layers (thickness 100 μm) formed on one surface of the polarizable electrodes 8 and 11 by plasma spraying.

The two stainless steel plates 1 and 12 are connected in parallel with the output leads 3a and 3b of the solar cell and the broken lines 14 and 15 by a method described later.

In the energy storage device having the above configuration, a device was prototyped by applying the following types of polarizable electrodes.

[A]

Activated carbon fiber cloth (weight per unit area 140 g / m ² , thickness 0.9 mm) obtained by directly carbonizing and activating cloth woven with phenol resin type fibers (Kynol fiber manufactured by Nippon Kynol Co., Ltd.).

[B]

The same phenolic resin fibers as above were activated by carbonization, which was cut into chops, mixed with natural pulp and made into paper (paper unit weight 70 g / m ² , thickness 0.4 mm, activated carbon fibers And the mixing ratio of natural pulp to the weight ratio of 7: 3).

[C]

The same phenolic resin fiber as above was activated by carbonization, this was cut into chops, mixed with tetrafluoroethylene resin powder, and compression molded (weight of molded product 70 g / m ² , thickness 0.5 m
In m, the mixing ratio of activated carbon fiber and resin powder is 100: 5 by weight.
The one you chose).

[D]

Oga charcoal-based powder activated carbon (particle size that passes through a 100-mesh sieve) and tetrafluoroethylene resin powder are mixed together, dissolved in methanol, and dispersed, which is applied to the surface of an aluminum foil with a thickness of 100 μm and dried (this In the example, an aluminum foil is used as the conductive material 7, 10 instead of the aluminum sprayed layer of FIG. 1).

(Example 2) Of the structure described in A of Example 1, the polarizable electrode of FIG.
11. Instead of the conductive electrode 10, an electrode that electrochemically occludes lithium in a Sn—Pb alloy plate, that is, an electrode that reversibly occludes and releases lithium by charging and discharging is used. As the electrolytic solution, propylene carbonate in which lithium perchlorate is dissolved is used.

(Example 3) In A of Example 1, nickel plates of the same size are used instead of the two stainless steel plates 1 and 12. In addition, the conductive electrode 7,
10 uses a sprayed nickel film, and the electrolytic solution is made of caustic potassium.
A 25% by weight aqueous solution is used.

Various characteristics of the energy storage device obtained by the above examples are shown in the following table.

Next, an example of a method of connecting the solar cell and the energy storage element will be described.

As described above, the photoelectric conversion unit and the capacitor or the battery unit are connected in parallel, and a concrete example is shown in FIGS.

FIG. 3 shows that the stainless steel plate 1 which is the substrate of the solar cell 6 is in direct contact with one output terminal 3b of the solar cell in series, and the other output terminal 3a is used for vapor deposition, plasma spraying, coating, etc. This is an example in which a conductor layer 16 formed by the method is connected to the facing stainless steel plate 12. Reference numeral 17 is an insulating layer such as resin.

In FIG. 4, the length of the facing stainless steel plate 12 is made longer than that of the stainless steel substrate 1, and the conductor layer 19 is provided at the end of this plate 12 via the insulating layer 18 by a method such as vapor deposition, and the output terminal This is an example in which 3a and the metal plate 12 are connected.

FIG. 5 shows a circuit configuration for preventing overcharging of a capacitor or a battery from a solar cell and a reverse current from flowing. Solar cell 20 and capacitor or battery 21, load 2
By disposing the diodes 23 and 24 between them and 2 can be prevented overcharge.

EFFECTS OF THE INVENTION As described above, according to the present invention, the photoelectric conversion unit and the energy storage unit are integrally configured via the substrate, so that a very small and thin energy generation and storage device is realized. . It has great utility as a semi-permanent maintenance-free power supply for backup power supplies for watches and various electronic devices.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a constitutional example of an energy storage device according to the present invention, FIG. 2 is an exploded perspective view thereof, FIG. 3 and FIG.
FIG. 5 is a perspective view of a main part showing a specific sequence of connections between the photoelectric conversion part and the energy storage part, and FIG. 5 is a circuit diagram showing a connection example of the photoelectric conversion part, the energy storage part, and the load. 1,12 …… Metal plate, 6 …… Solar cell, 8 …… Polarizable electrode,
9 …… Separator, 11 …… Counter electrode, 13 …… Sealant.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location H01L 31/042 H01M 10/40 Z 10/46 H01G 9/20 (72) Inventor Ichiro Tanahashi Osaka Prefecture Kadoma City Kadoma 1006, Matsushita Electric Industrial Co., Ltd. (56) Reference JP 59-214215 (JP, A) JP 59-48917 (JP, A) Actual development 57-66868 (JP, U) Actual development Sho 57-66561 (JP, U) Actual opening Sho-57-104551 (JP, U) Actual opening Sho-59-115378 (JP, U)

Claims (1)

[Claims] 1. An energy storage unit composed of a pair of polarizable electrodes and an electrolytic solution, which are opposed to each other with a separator interposed therebetween, a metal plate constituting a current collector of the one electrode, and a metal plate supported on one surface of the metal plate. Further, a flat plate-shaped energy storage device comprising a solar cell having the metal plate as one electrode, and the energy storage section and the solar cell are connected in parallel.