JPH0393170A - Actuation of solid secondary battery and power supply device - Google Patents

Abstract

PURPOSE:To maintain high capacity at high temperature by performing constant- potential charging at the higher potential at the higher temperature of a temperature condition at a working time in a solid secondary battery for a cycle service wherein a copper chevrel phase compound is used as a material for a positive electrode and a negative electrode while an Rb ion conductive solid electrolyte is used as a solid electrolyte. CONSTITUTION:In a solid secondary battery for a cycle service, wherein a composition of a copper chevrel phase compound Cu2Mo0S3 is used for both electrodes as a material for a positive electrode and a negative electrode, while an Rb ion conductive solid electrolyte is used as a solid electrolyte, the potential of the positive electrode is but a little shifted to the higher side when a surrounding temperature rises. Since accordingly charge is little by little short at low set potential equally to a room temperature, the set potential is raised little by little according to a rise of a temperature. Lack of charge is thereby suppressed at a high temperature to attain a long life.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of operating a solid-state secondary battery for cycle service whose constituent materials are all solid and to a power supply device.

Conventional technology Among the batteries used as various power sources, so-called solid-state batteries, whose constituent materials are all solid, have no leakage, are expected to be highly reliable, and can be made smaller and lighter, so they are used as primary and secondary batteries. Both batteries have been attracting attention. Currently, it is mainly being considered for memory backup of various devices.

The electrolytes in this solid battery include LI" ion conductive solid electrolyte, Ag◆ ion conductive solid electrolyte, H ion conductive solid electrolyte, and R b Cu a I+.
sCls. Cu such as s, CuI-Cu20-MoO*
4-ion conductive solid electrolytes are featured.

In addition, examples of positive electrode materials include CuTi, AgTi nails, and Sheprell phase compounds such as CuvMQ@S#-z and FewMoaS*-z.
u% A g, L i +. Although Chevrel phase compounds similar to those for positive electrodes have been tried in the sWO book, among these, steel Chevrel phase compounds are preferred for positive and negative electrodes.Especially, using the combination of Cu*Mo●S● for both electrodes and using Rb as a solid electrolyte. A solid secondary battery using an ion conductive solid electrolyte {1) Compared to other systems, it is capable of rapid charging and discharging, has a long life, and has good overdischarge characteristics, so it is suitable as a secondary battery for cycle service. Although it is superior to other solid-state systems, constant voltage charging may be considered as a general charging method during actual use. 0.50~0 to avoid deterioration,
Problems to be solved by the invention with the upper limit of 60V/cell Selecting a copper Sheprel phase compound with excellent reversibility as the material for the positive and negative electrodes.In particular, using the combination of Cu Mo@S● for both electrodes as a solid electrolyte. RbC11 a l I
．． sc ] s. Solid secondary batteries for service cycles using Rb-based ion-conductive solid electrolytes such as When used at high temperatures, some batteries show a decrease in discharge capacity after a relatively small number of cycles even when charged at constant voltage.Means for solving the problem Copper Chevrel phase compounds, especially Cu-elevation Mo●S, are used as materials for the positive and negative electrodes. Select the set of ● and use R as the solid electrolyte.
bcuaf. sc Is. s, etc. 77) A solid secondary battery for cycle service using an Rb-based ion-conductive solid electrolyte, characterized in that constant potential charging is performed in which the potential during charging is increased as the temperature increases. Copper Sheprel is used as a material for the positive and negative electrodes in a power supply device for a solid-state secondary battery for cycle service, which is equipped with a constant-potential charger that performs constant-potential charging. Phase compound Cu
A solid secondary battery for cycle service using a combination of Shun Mo●S● for both electrodes and an Rb-based ion-conductive solid electrolyte as the solid electrolyte. .5 6 V/cell is considered as the upper limit for charging. In this case, lower is better1,
However, it turns out that as the ambient temperature rises, the potential of the positive electrode shifts to a higher side, albeit slightly. Therefore, if the set potential is as low as at room temperature, charging will gradually become insufficient. Although it is possible to achieve a long life by suppressing insufficient charging at high temperatures by gradually increasing the temperature, copper Chevrell (Cu*Mo●S●) is used as the material for the positive electrode in this embodiment.In addition, RbCu4I+ is used as the electrolyte. sCII1
20wtK A positive electrode sheet with a thickness of 300 μm was prepared using commercially available polyethylene as a binder at 6wt%.4-X Copper Sheprel (Cu*Mo@S●) was also used for the negative electrode. The same electrolyte R as in the positive electrode
bCu4I+. sC 1s. 20 wt% of s and a binder (
A similar negative electrode sheet was prepared using R bCu4I+.6wt%) as the electrolyte. sCl*. Polyethylene was added to 13 wt% as a binder to prepare an electrolyte sheet with a thickness of 100 μm.Next, each sheet was heated to 160°C in the order of positive electrode electrolyte and negative electrode. 500kg/cm with press machine
Next, conductive carbon paper bonded with a commercially available binder was applied to both sides of the battery element thus obtained for 130'tl. A 0.2 mm thick laminate sheet made of aluminum with a polyethylene film placed only around the battery, which had been integrated under a pressure of 400 kg/cm', was placed on both sides of the battery element with polyethylene on the inside and heated to 140°C. Using a heated roller press, the battery element is placed under heat and pressure is applied to the area around the battery to a pressure of 300 kg/cm. Through this operation, the battery element is pressurized, and the polyethylene is welded around the battery to complete the sealing. Regarding the lead plate, in this example, the size of the battery with the Cu thin plate taken out to the outside is 15 x 30 mm.
After completing the test, this battery is 0.54V at 20℃ and 65℃.
0.56VS at 100℃ 0.58Vl. : This battery was charged with a constant voltage charger controlled so that A
Tosumo Naho Discharging is performed at a constant current of 0.5 mA to 0.3 V at the same temperature as charging.For comparison, all 0.
．． 54V constant voltage charged battery & all 0
, 5 6 V as α, 0.58 V as D, and using 9 or more A-D batteries, 20°C and 65°C --. −
．． /"- and 100℃ to check its lifespan?Q.The results are as shown in Tables 1 to 3.9Table 1 is 2.
The cycle and capacity (mAh) at 0°C are shown.As is clear from these results, increasing the set voltage increases the initial capacity, but the life is slightly shorter.
At the next temperature of 65℃ (as shown in Table 2 above, if the set voltage is low like B, the discharge capacity will be small from the beginning of the cycle). Finally, at 100°C, as shown in Table 3, when the set voltage is low as in &C, the discharge capacity is small and the decrease due to cycles is also slight. Select a combination of Mo@S●R as a solid electrolyte
b Cu a I +. sC 1 m. R such as s
In solid secondary batteries that require cycle characteristics using b-type ion conductive solid electrolytes, the higher the temperature conditions during use, the higher the potential.
It is possible to maintain high capacity, especially at high temperatures.

Claims (3)

[Claims] (1) A copper Chevrel phase compound is used as the material for the positive electrode and the negative electrode, and RbCu_4I_1_. _5C
l_3_. Operation of a solid secondary battery using an Rb-based ion conductive solid electrolyte such as __6, characterized in that the higher the temperature condition during use, the higher the constant potential charging is performed. Law. (2) A copper Chevrel phase compound is used as the material for the positive electrode and the negative electrode, and RbCu_4I_1_. _5C
l_3_. A solid secondary battery using an Rb-based ion-conductive solid electrolyte such as _5 is equipped with a constant-potential charger that performs constant-potential charging at a higher potential as the temperature condition during use becomes higher. A solid-state secondary battery power supply device. (3) The method of operating a solid secondary battery according to claim 1, wherein the set potential is about 0.52 to 0.56 V near room temperature and about 0.56 to 0.6 V at about 100°C.