JPH01106473A - Light emitting secondary cell - Google Patents

Abstract

PURPOSE:To enable a cell to be produced compactly and to allow it to be stable thermally by using Chevrel compound for cell active substance which is a constituting element of secondary cell part and by using a solid electrolyte as an electrolyte. CONSTITUTION:With a positive-polarity layer 7 and a negative-polarity layer 9, each powder body of copper Chevrel compound and solid electrolyte is blended in a weight ratio of 8:2 beforehand and is subject to press mold at a pressure of 3ton/cm<2>. Then, it is annealed and then is crashed into powder. After this, blended agent 100 weight part is blended with a toluene solution 10 weight part to create a blended agent slurry and it is screen-printed. Also, with the solid electrolyte layer 7, the solid electrolyte powder 100 weight part is blended with the toluene solution 10 weight part to create solid electrolyte slurry and then it is screen-printed. Then, the positive-polarity pyroelectric layer 10 which is the same as a negative pyroelectric layer 6 is created and it is conjugated with a transparent electrode 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an all-solid-state photovoltaic secondary battery consisting of a solar cell and an all-solid-state secondary battery, and particularly to a photovoltaic secondary battery that functions as a driving power source for various power consumption devices. Regarding the next battery.

Conventional Technology A number of power supply devices have been proposed to date that integrate solar cells and secondary batteries, store the electricity generated by the solar cells in the secondary battery, and can be used as a power source regardless of the power source (
Masao Kaneko Electronics P97-104, 1988
).

Problems to be Solved by the Invention However, in most conventional batteries, a liquid electrolyte was used as a component of the secondary battery. Since Hama uses a liquid electrolyte, it is difficult to integrate it with a solar cell due to liquid leakage, and when countermeasures were taken, the structure became complicated and large. There are also examples of using non-solvent electrolytes to solve this problem.

However, when using a non-solution electrolyte, in order to obtain a large charge/discharge current, the electrolyte itself must first have high ionic conductivity, and at the same time, the active material of the secondary battery must be It can be fully charged without overcharging with the electromotive voltage generated by the solar cell, and the charge/discharge reaction is highly reversible and has low reaction resistance.In addition, the solar cell is exposed to direct sunlight and is not affected by thermal effects. It must have excellent heat resistance as it will be exposed to a lot of heat. Until now, there has been no combination of electrolyte and active material that satisfies all of these conditions.

Means for Solving the Problems In view of the above problems, the present invention uses a Chevrel compound as a battery active material, which is a component of the secondary battery part, and uses a solid electrolyte as an electrolyte.

Function As described above, if a solid substance is used as the stain solute, there is no fear of liquid leakage, and therefore the structure becomes simple and miniaturization becomes easy. In addition, secondary batteries using Chevrel compounds as active materials have excellent reversibility during battery charging and discharging reactions, and can be fully charged at o and e (V) without overcharging. As a solar cell having this photovoltaic voltage, silicon or the like may be used (patent application No. 61
-26459).

In addition, Chevrel compound and solid electrolyte each have 100%
Since it is extremely thermally stable up to 0° C. and 150″c, it satisfies all the requirements for an all-solid-state photovoltaic battery as pointed out in the above-mentioned problems.

Example (Example 1) FIG. 1 is a sectional view showing the structure of a photovoltaic secondary battery that is an example of the present invention. Size 20 x 20ff, thickness 1H
A p-type S1 layer 3 is formed by CVD on a transparent current collector 2 in which In2O3 is deposited on a glass substrate 1 of 0.1 μm in thickness.
formation, and then continuously by the above-mentioned CVD method to form l-type Si[4
and n jJ S i layers 6 each having a thickness of 0.1 μm are formed. Next, a negative electrode current collector layer 6 mainly composed of carbon is formed on the n-type Si layer 5 by a screen printing method, and then a copper Chevrel compound C is formed by the screen printing method.
Negative electrode layer 7 mainly composed of u 4Mo e Sa, Rb
Cu a I *, 5 C41' 3.5. Solid electrolyte layer 8, copper Chevrel compound Cu 2Mo
A positive electrode layer 9 mainly composed of e S 7 and B was sequentially formed. The thickness of the three layers mentioned above is approximately 111M. The above-mentioned positive electrode layer 7 and negative electrode layer 9 were prepared by mixing the above-mentioned copper Chevrel compound and the above-mentioned solid electrolyte powders in advance at a weight ratio of 8:2, press-molding them under a pressure of 3 ton/cd, and then heating them at 200°C. Anneal for 17 hours and then grind. Furthermore, 100 parts by weight of this mixture was added to 1 part of toluene solution.
0 parts by weight to prepare a mixture slurry, which was screen printed. The solid electrolyte layer 7 was created by mixing 10 parts by weight of the solid electrolyte powder with 10 parts by weight of a toluene solution to create a solid electrolyte slurry, which was screen printed. Next, a positive electrode current collector layer 10 identical to the negative electrode current collector layer 6 was formed on the positive electrode layer s, and this was bonded to the transparent electrode 2. Reference numerals 11 and 12 are lead terminals, and finally the whole was sealed with a sealed package 13 made of epoxy resin to create a photovoltaic secondary battery A.

The charging/discharging reaction of the photovoltaic secondary battery thus produced is as shown below.

When the silicon layer forming the p-1-n junction is irradiated with light, electrons excited from the valence band pass through the conduction band and are collected at the negative current collecting electrode 6. (Cu++e-)→Cu4
+, induces the reaction indicated by Mo6S8. In line with this, in the positive electrode 9, Cu2Mo6S7.8 → Cu2-, Mo687.80X
A reaction represented by (Cu++e-) occurs, and electrons generated by this reaction flow through the positive electrode current collector 1o and from the transparent electrode 2 into the p-type S1 layer 3, forming a flow of electrons.

This is the current in a photovoltaic reaction. Then, after a certain period of time, the secondary battery part becomes fully charged, and the copper Chevrel compound that is the battery active material is MO at the positive electrode.
s S s, and the negative electrode has a composition of Cu6Mo6S8. When fully charged, the electromotive force generated in the solar cell is M Oe, S 7. s and Cu s MO68
The potential difference with s cancels out the charge, and charging automatically stops.

Further, discharge is performed through lead terminals 11 and 12.

In a copper Chevrel compound, the lower the Cu composition ratio, the higher the electrical energy, and when the lead terminals 11 and 12 are joined, the positive electrode 9 becomes MoeS 7. s 1X (Cu”+e −) →Cu,
MoeS 7. a In the negative electrode 7, Cu, Mo6S8-+Cu6-! Mo6S8+X(Cu
A reaction indicated by ``+e-'' occurs naturally. This is a discharge reaction. Note that a diode is formed between the electrode 2 and the electrode 6 by a p-1-n junction of silicon, so the direction of discharge is No current flows and there is no need to worry about internal short circuits.

The following charge/discharge cycle measurements were performed on the photovoltaic secondary battery A.

First, a resistor of Ω is connected to lead terminals 11 and 12 as an external load. On the other hand, after irradiating it with sunlight for 1 hour to generate photovoltaic power, it was left in a dark place for 1 hour to perform constant resistance discharge. Figure 2 shows the voltage applied to the load resistance measured when this operation was repeated. The vertical axis shows voltage, and the horizontal axis shows elapsed time. Further, FIG. 3 shows the cycle characteristics of the terminal voltage at the end of discharge during the above operation. As can be seen from FIG. 3, the performance has hardly deteriorated even after 1000 photodischarge cycles.

Further, in order to confirm the thermal stability of the battery A, the cycle characteristic test was conducted at 100°C. The results are shown in FIG. As can be seen, the battery according to this example also exhibits excellent thermal characteristics.

(Example 2) A photovoltaic secondary battery having flexibility as a whole was created. Its cross-sectional structure is the same as that in FIG. 1 of Example 1. On a transparent current collector 2, In2O3 was deposited on a polyimide film 1 with a size of 20x20m and a thickness of 0.1jl11,
The p-type St layer 3 is formed to a thickness of 0.1 μm by the CVD method, and then continuously by the CVD method described above! An lli-type St layer 4 and an n-type Si layer 6 were each formed to have a thickness of 0.1 μm. Next, a negative electrode current collector layer 6 mainly made of carbon is placed on the n-type T layer 5.
The copper Chevrel compound Cu4Mo638 was formed by the screen printing method, and then the copper Chevrel compound Cu4Mo638 was formed by the screen printing method.
Negative electrode layer 7 mainly composed of RbCu411.6C13,5
Solid electrolyte layer 8 represented by copper Chevrel compound Cu
A positive electrode layer 9 mainly composed of 2 M Ocs S -r,s was sequentially formed. The film thicknesses of the five layers mentioned above were all approximately 1 MII. The method for producing the positive electrode layer 7 and the negative electrode layer 9 is to prepare powders of the copper Chevrel compound and the solid electrolyte.
After pre-mixing at a weight ratio of = 2 and press molding under a pressure of 3 ton/crI, annealing was performed at 2oo°C for 17 hours, and then the mixture was pulverized. Further, 10 parts by weight of this mixture and 1 part by weight of the styrene-ethylene-butadiene-styrene copolymer were mixed with 10 parts by weight of a toluene solution to prepare a mixture slurry, which was screen printed. The solid electrolyte layer 7 was created by mixing 10 parts by weight of the solid electrolyte powder and 1 part by weight of the styrene-ethylene-butadiene-styrene copolymer with 10 parts by weight of a toluene solution to create a solid electrolyte slurry, which was screened. Printed.

Next, a positive electrode current collector layer 1o identical to the negative electrode current collector layer 6 was formed on the positive electrode layer 9, and this was bonded to the transparent electrode 2.

Reference numerals 11 and 12 are lead terminals, and finally the whole was sealed with a sealed package 13 made of epoxy resin to create a photovoltaic secondary battery B.

FIGS. 4 and 4 show the results of the same charge-discharge cycle characteristic test as in Example 1 for this photovoltaic secondary battery B. It can be seen that the photovoltaic secondary battery B of Example 2 also has substantially the same performance as the photovoltaic secondary battery A of Example 1.

(Example 3) One of the features of the photovoltaic secondary battery according to the present invention is that the manufacturing method is easy. In other words, it is completed by electrically connecting the all-solid-state secondary battery part to the solar cell that has been created in advance and integrating it from the back. According to this manufacturing method, the solid secondary battery portion can be attached to any solar cell from the back side, regardless of the electromotive voltage of the solar cell used. This will be explained below using this example.

A PN junction St solar cell shown in FIG. 7 was prepared in advance. 21 is a resin printed circuit board with external dimensions of 27.5 x 29.51111, 22 is an A4 electrode, 23 is a P-N junction solar cell element, 24 is a transparent electrode, 26 is a sealed package, and the operating voltage is 1.6 volts. It is. .

Next, a solid secondary battery portion 39 is placed on the back side of the printed circuit board 3o.
A solar cell portion 31 was created on the other side.

The solid-state secondary battery element has 3 cells connected in series, and this
As shown in the figure. 32 is a positive electrode terminal, 33 is a positive electrode layer, 34 is a solid electrolyte layer, 36 is a negative electrode layer, 36 is a connection lead, 37 is a negative electrode terminal, 38 is a resin sealed package, and the material, thickness, and All the manufacturing methods were the same as those for the battery of Example 1.

FIGS. 9 and 10 show the results of the same charge-discharge cycle characteristic test as in Example 1 for Battery C of this example prepared in this manner. It can be seen that the all-solid-state photovoltaic secondary battery of Example 3 also has the same performance as the photovoltaic secondary battery of Example 1 and #1.

As described above, according to the present invention, a product with excellent thermal stability can be obtained.
A small and thin all-solid-state photovoltaic secondary battery can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an all-solid-state photovoltaic secondary battery according to an embodiment of the present invention, FIGS. 2, 3, and 4 are characteristic diagrams of the same photovoltaic secondary battery, and FIGS. FIG. 6 is a characteristic diagram of a photovoltaic secondary battery according to another embodiment of the present invention, FIG. 7 is a configuration diagram of a solar cell portion of a photovoltaic secondary battery according to another embodiment of the present invention, and FIG. 7 is an overall configuration diagram of a photovoltaic secondary battery having the solar cell portion shown in FIG. 7 as a component, and FIGS. 9 and 10 are characteristic diagrams of the photovoltaic secondary battery shown in FIG. 8. 1...Supporting base, 2...Transparent electrode, 3
...p-type Si, 4...i-type Si, s.
...N-type st, e...Collector electrode, 7...
...Negative electrode, 8...Solid electrolyte, 9...
...Positive electrode, 10...Collecting electrode, 11...
・Positive lead terminal, 12...Negative lead terminal,
13... Sealed package. Name of agent: Patent attorney Toshio Nakao and 1 other person/-
--Support base 7 Negative electrode 2-itQ iUi & 8 Solid avzs page 3-f
”is, l q correct a4=- 3L
// Work Type I Each 1st Figure 5-7L i
Toad i 12 Electrical lead terminal 4, /θ---collection t,
T-t! j ts t, lamp cage ts2 diagram passing time (hours) Fig. 3 / 6120 /θρ0 number of cycles (hundreds) Fig. 4 number of cycles per cycle (times) Fig. 5 θ / 234 time to open (time) 6th Fig. 19ρ l〃θ Length angle number (rm) Fig. 7 Fig. 8 Fig. 9 Fig. 9 0 / 2 3 4 Pressing time (time closed)

Claims (3)

[Claims] (1) An all-solid-state secondary battery formed by sequentially laminating a positive electrode molded body layer mainly composed of a Chevrel compound, a solid electrolyte molded body layer, and a negative electrode molded body layer mainly composed of a Chevrel compound; A photovoltaic secondary battery characterized in that it is integrally configured by electrically connecting a solar cell formed with a photoelectric conversion film interposed between electrodes. (2) The positive electrode molded body layer and the negative electrode molded body layer are a mixture consisting of at least each electrode main material and a plastic binder, and the solid electrolyte molded body layer is a solid consisting of a solid electrolyte, a plastic binder, and, if necessary, a core material. Claim 1 is characterized in that the electrolyte molded body is an all-solid-state secondary battery formed from the electrolyte molded body, and is electrically connected to a photoelectric conversion element on a flexible transparent resin substrate. photovoltaic secondary battery. (3) The Chevrel compound is a copper Chevrel compound or a silver Chevrel compound, and correspondingly, the solid electrolyte is a copper ion conductive solid electrolyte or a silver ion conductive solid electrolyte, respectively. The photovoltaic secondary battery according to item 1 or 2.