JPH0384870A - Manufacture of solid secondary cell - Google Patents

Abstract

PURPOSE:To improve the close contact of an electrolyte layer and electrode 2 layers by containing the side including just more electrolyte to the core member as the center in the electrolyte layer, to a positive electrode layer, and the side including more electrode material in the electrode layers, to the electrolyte layer, and unifying them. CONSTITUTION:When a core member is provided in an electrolyte layer, the side including more electrolyte to the core as the center is contacted to a positive electrode layer and unified. And when a porous core material is provided in an electrode layer, the side including more electrode material to the core as the center is contacted to the electrolyte layer and unified. And, finally, when two electrolyte layers are provided and unified, the sides including more electrolyte to the core members as the centers are contacted to the electrode layer respectively and unified. Consequently, the close contact of the electrode layer or layers and the electrode layers can be improved.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a method for manufacturing so-called solid-state secondary batteries whose constituent materials are all solid.Prior art The present invention relates to a method for manufacturing so-called solid-state secondary batteries whose constituent materials are all solid. Certain so-called solid-state batteries are attracting attention as both primary and secondary batteries because they do not leak, are expected to be highly reliable, and can be made smaller and lighter.Currently, they are mainly considered for memory backup in various devices. ing.

In this solid-state battery, a solid electrolyte for moving ions within the battery is particularly important, and Li0 ion conductive solid electrolytes such as LiI and LiN, RbA g
Ag'' ion conductive solid electrolyte such as AgI-Agg○, AgI-MOO3, H+ ion conductive solid electrolyte, and Rb Cu4I s, 5C1s, s.

Cu" ion conductive solid electrolytes such as CuI-CuaO-Mo03 are being discussed. As cathode materials, Cus, +TiS2, Ag@
, +Ti5g, Cut, +Nb5a, Ag@, +NbS
*, W Os, and CuvMo@s*-zs Fe
Chevrel phase compounds such as vMosS*-2 are mentioned;
Although attempts have been made to use i+, 5WOs, and Chevrel phase compounds similar to those used for positive electrodes, the structure of these batteries is similar to other batteries, with active electrodes as positive and negative electrodes on both sides of the electrolyte layer, which mainly consists of an electrolyte and a binder. It is common practice to arrange an electrode layer consisting mainly of a substance and a binder. Porous core materials such as screens are used for the electrode layer and electrolyte layer in order to facilitate handling and simplify the manufacturing process. It is preferable to use such a porous core material and to form a sheet using a binder.For batteries using solid electrolytes, contact between the electrolyte layer and the electrode layer is particularly important. From this point of view, the problem that the present invention aims to solve is that when a sheet is formed using such a core material, it is industrially difficult to place the core material exactly in the center of the electrode layer or electrolyte layer. Although it is impossible in mass production, if no consideration is given to the uneven distribution of the core material, variations in the adhesion between the electrolyte layer and the electrode layer will occur. When a porous core material is placed on the electrode layer (the side with more electrolyte is in contact with the positive electrode layer) First, the side with more electrode material is in contact with the electrolyte layer, but when finally placing two electrolyte layers and integrating them, (centering on the core material of each electrolyte layer, the side with more electrolyte is placed in contact with the electrolyte layer. In the electrolyte layer, the side with as much electrolyte layer as possible around the core material should be in contact with the positive electrode layer, and in the electrode layer, the side with more electrode material should be in contact with the electrolyte and integrated. As a result, it was possible to improve the adhesion between the electrolyte layer and the electrode layer, and the reliability was improved compared to the case without such considerations.Example: Copper Chevrel (CuaMos30) was used as a material for electrodes at 1100CJ. 1.X, with RbCu4 as an electrolyte
Using 1g of I+, sC, and s, add 500g of this powder and mix while heating to 200℃.To the mixed powder obtained in this way, add 5g of commercially available acrylic resin as a binder.
Add the acetone solution and stir thoroughly to obtain a paste so that the acetone solution is 50% by weight.An electrode sheet with an average thickness of 350μm is made using the well-known doctor blade method using a 50-mesh polypropylene screen with a wire diameter of 100μrrL as the core material. When we examined the cross-sections on both sides of this core material, we found that one side had an extra layer of 10 to 20 μm, so we found that it was not correct.
For both negative electrode sheets, set this side to be in contact with the electrolyte sheet, and use RbCu4I+, sc Ia, and s as the electrolyte.L%
As a binder, 10wt% of acrylic resin is used.
Add the acetone solution and stir thoroughly to obtain a paste. An electrolyte sheet with an average thickness of 0.10 mm is prepared by the well-known doctor blade method using a 50-mesh polypropylene screen with a wire diameter of 100 μm as a core material. In this case as well, we examined the cross sections on both sides of this core material and found that one side had an extra layer of 5 to 10 μm.This side was placed on the positive electrode sheet side, and the negative electrode sheet and the electrolyte were removed in this way. Sheet 3
The layers were integrated under pressure at 120° C. and 600 kg/am2. Then, a commercially available carbon film in which fine carbon black powder was dispersed in rubber was applied as a current collector to both sides of the battery element thus obtained. Furthermore, a Cu plate with a thickness of 0.3 m and a diameter of 26 mm was placed on the outside.
0t, 500kg/cm" pressurization integrated and t
1. Construct the battery by painting the area around the battery with room temperature curing epoxy resin. This battery is referred to as A.Next, for comparison, we will design a battery in which the electrolyte sheet and the electrode sheet are integrated without paying any consideration to the uneven distribution of the core material regarding the electrode sheet and electrolyte sheet.
Using 20 cells each of A and B batteries with t and t as above,
First, compare the discharge voltage and capacity during normal charging and discharging.
, charging up to 0.57V at 1.0mA! -2,5mA
When discharging to 0.3V at &A, the flat voltage was 0.48+0. OI V, discharge capacity 19.8±0.2
mAh, whereas in B it was 0.47±
0.02 V and 19.5 ± 4 mAh, and there was little variation in A in each case.9 Therefore, we next investigated the life characteristics of each battery under these charging and discharging conditions.
Use fQ for each cell, set the ambient temperature to 25°C, and f.
The number of cycles at which the viscosity discharge capacity deteriorates to 60% of its initial value was 1100 ± 50 cycles for A, while it was 950 ± 130 cycles for B. It is clear from this result that A Effects of the Invention In the manufacturing method of solid-state secondary batteries, in the electrolyte layer, the core material is centered, and the side with as much electrolyte layer as possible is in contact with the positive electrode layer, and in the electrode layer, the electrode material is By integrating the side with the larger amount in contact with the electrolyte, it is possible to suppress the increase in internal resistance during charging and discharging of the battery, reducing variations in discharge performance,
Even if longer life can be achieved

Claims (1)

[Scope of Claims] (1) When integrating an electrolyte layer having a porous core material and an electrolyte layer mainly consisting of a binder by disposing an electrode layer mainly consisting of an electrode material and a binder on both sides of the electrolyte layer having a porous core material and an electrolyte layer mainly consisting of a binder. A method for producing a solid secondary battery, characterized in that the core material of the electrolyte layer is integrated with the electrolyte-rich side thereof being in contact with the positive electrode layer. (2) When integrating an electrode layer mainly consisting of an electrode material having a porous core material and a binder on both sides of an electrolyte layer mainly consisting of an electrolyte and a binder, 1. A method for manufacturing a solid-state secondary battery, which comprises integrating a core material with the side containing more electrode material in contact with an electrolyte layer. (3) When integrating an electrolyte layer with a porous core material and an electrolyte layer mainly with a binder by disposing an electrode layer mainly with an electrode material with a porous core material and a binder on both sides of the electrolyte layer with a porous core material and a binder. The electrode layer is integrated so that the side with more electrode material around the core material is in contact with the electrolyte layer, and the side with more electrolyte around the core material of the electrolyte layer is in contact with the positive electrode layer. A method for manufacturing a solid-state secondary battery characterized by: (4) Arranging two electrolyte layers consisting mainly of an electrolyte with a porous core material and a binder, and integrating electrode layers mainly consisting of an electrode material and a binder on both sides of these electrolyte layers. A method for manufacturing a solid-state secondary battery, characterized in that each electrolyte layer is integrated with the core material in such a manner that the side containing more electrolyte is in contact with each electrode layer.