JPH01283765A - Organic electrolyte cell - Google Patents

Abstract

PURPOSE:To make it possible to obtain an organic electrolyte cell with a low inner resistance during the discharge and an excellent pulse property by loading an aluminum foaming substance on the reaction surface of a negative electrode lithium. CONSTITUTION:An aluminum foaming substance 6 is loaded at the reaction surface side of lithium 3 to be buried partially in a lithium metal 3 by applying a pressure. As a result, the electrolyte is permeated in the aluminum foaming substance 6, and the reduction os the electrolyte is prevented to prevent the deterioration of reaction efficiency. Moreover, in the aluminum foaming substance 6, the surface area is increased compared with a normal plate-form or a foilform aluminum. As a result, the alloying speed of the aluminum and the lithium is increased, and an even and minute particle-form of alloy layer can be obtained. Consequently, even when the aluminum layer is made thick, the aluminum part not alloyed is never generated, and a low resistance, an excellent pulse discharge performance, and a stable discharge property can be obtained.

Description

[Detailed description of the invention] Industrial applications The present invention relates to improvements in organic electrolyte batteries.

BACKGROUND OF THE INVENTION Organic electrolyte batteries using lithium as an active material have high energy density and are attracting attention as power sources for various small electronic devices including electronic watches. However, since metallic lithium is very active, the internal resistance increases due to the formation of a lithium compound film on the lithium surface, and furthermore, as the discharge progresses, the internal resistance increases due to a decrease in the lithium surface area. For this reason, when an electronic watch or the like performs full pulse discharge, the drop in closed circuit voltage increases, making it impossible to use the battery capacity effectively to the end.

In order to eliminate these drawbacks, a proposal has been made to attach aluminum foil to the lithium surface and increase the surface area of the negative electrode through the miniaturization and wrinkles of the negative electrode caused by the formation of a 1-alloy layer, thereby lowering the internal resistance. There is.

Problems to be Solved by the Invention However, 1. If ordinary aluminum foil is used, the electrolyte will be reduced by the volume of the aluminum foil, which will not only reduce the reaction efficiency of the battery and cause a decrease in capacity, but also cause the pulse discharge characteristics to deteriorate at the end of discharge. A decrease occurs. In addition, with ordinary aluminum foil, the contact area with lithium is small, so alloying does not proceed uniformly, and the alloy layer on the surface facing the positive electrode has coarse particles, and the increase in the negative electrode surface area is small, so the pulse characteristics are also satisfactory. I can't get anything. Furthermore, when the thickness of the aluminum foil becomes thicker, there is a problem that aluminum remains unalloyed, inhibits the reaction of lithium, and reduces the discharge capacity.

It is an object of the present invention to solve the above-mentioned problems, to provide an organic electrolyte battery that reduces the loss of electrolyte solution, uniformly forms a single alloy, has low internal resistance, and is excellent in pulse discharge.

Means for Solving the Problems In order to solve these problems, the present invention constructs a battery by placing an aluminum foam on the lithium reaction surface of the negative electrode.

Function: By constructing a battery using this aluminum foam, the electrolyte permeates into the aluminum foam, preventing the electrolyte from decreasing and reducing reaction efficiency. Moreover, the surface area of aluminum foam is larger than that of ordinary plate-shaped or foil-shaped aluminum. Therefore, the speed of alloying of aluminum and lithium is fast.

A uniform, finely grained alloy layer can be obtained.

Even when the aluminum layer is made thicker, there are no aluminum parts that are not alloyed, resulting in low internal resistance and excellent pulse discharge characteristics.

It becomes possible to obtain stable discharge characteristics.

Example The present invention will be explained in detail below.

FIG. 1 shows a button-type organic electrolyte battery based on lithium-copper oxide. In Figure 1, 1 is a positive electrode case made by punching a stainless steel plate with a thickness of 02 mm and nickel plated on one side, 2 is a stainless steel sealing plate with a thickness of 0.2 mm and nickel plated on one side, and 3 is a negative electrode active material. The metal lithium is crimped and fixed to the uneven portion of the inner surface of the sealing plate 2. 4 is formed by mixing an active material containing copper oxide as a main component with graphite as a conductive material and a binder, placing this in a positive electrode case, and pressurizing it together with a stainless steel positive electrode ring 6 having an angular cross section. The deposited positive electrode 6 was an aluminum foam according to the present invention having a thickness of 100 μm, and was placed on the lithium reaction surface side under pressure so that a portion of the positive electrode was buried in the lithium metal. 7 is a polypropylene separator, 8
ij: Polypropylene gasket. The electrolyte used was a solution in which lithium perchlorate was dissolved in a mixed organic solvent of propylene carbonate and 1-2 dimethoxyethane, and the battery size was 9.5 ff in outer diameter and 2.7 mm in height. .

Figure 2 shows a battery of the above size with a resistance of 30 Ω at a temperature of 20'C.
This shows the characteristics when a load is connected and discharged. In the figure, M is a battery using the aluminum foam of the present invention, B is a battery using a normal aluminum foil, and C is a discharge curve of a battery using no aluminum foil.

Figure 3 shows a load of 6 Ω at 7.8 m/s at -10°C.
The closed-circuit voltage after 72 hours of 5s・C is shown by depth of discharge. It is a battery that does not use.

In the examples, an example was described in which copper oxide was used as the positive electrode active material, but similar effects were obtained when carbon fluoride, manganese dioxide, iron sulfide, bismuth oxide, etc. were used in the positive electrode.

Effects of the Invention As described above, by placing an aluminum foam on the reaction surface of the lithium negative electrode, an organic electrolyte battery with low internal resistance during discharge and excellent pulse characteristics was obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an organic electrolyte battery according to an embodiment of the present invention, FIG. 2 is a diagram showing a discharge curve, and FIG. 3 is a diagram showing closed circuit voltage depending on the depth of discharge. 1...Positive electrode case, 2...Sealing plate, 3
・・・・・・Negative electrode. 4...Positive electrode, 6...Positive electrode ring, 6.
... Aluminum foam, 7 ... Separator, 8 ... Gasket. Name of agent: Patent attorney Toshio Nakao and 1 other person1-
--Case 2--One side T carpet 5・-Original i lithog E---Aluminum: Tsu 4 Tei 55 Hamamoto 7---Ha'''L-ta 8-11' insert, To 3rd Tuhoi Uma Cliff (Tears)

Claims (1)

[Claims] An organic electrolyte battery comprising a negative electrode containing lithium as an active material, an organic electrolyte, and a positive electrode, characterized in that an aluminum foam is placed on the reaction side surface of the negative electrode.