JPS5947433B2 - battery - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a primary battery that is small in size and has a large discharge capacity.
More specifically, the present invention relates to a primary battery using lithium as a negative active material.

Many proposals have been made for high energy density batteries that use lithium as a negative electrode active material. For example, halogens such as Br2 and 12, CuF22AgF2, AgF, NiF2, cUct, etc., have been proposed as positive electrode active materials.
23Agct2, Nict23C0F3, CrF3,
MnF3, SbF3, CdF23AsF32HgF2C
Metal halides such as uBr, CbCt2, PbCt2 and c0ct2, AgSCN, CuSCN and N
i(SCN) nasal metal halide, Noo2,
Cr2O3, Ri2o5, sno2, pbo2, TiO2
, Bl02, Cr02, Fe304, NiO, AgO,
HgO, Cl12O, ClI.

, Ag2W04 etc., NiSX, Ag
Metal sulfides such as BS, CIIBS, Pb2B2S5 and MnB4S4, layered compounds such as TaS2, NbSe and WS2, graphite fluoride, as well as organic compounds such as benzoquinones, dinitrobenzene, and spot3.
Batteries using oxyhalides such as 2soct2 and so4ct2 have been proposed. Specifically, for example, batteries are known that use graphite and fluorine intercalation compounds as positive electrode active materials, and lithium metal as negative electrode active materials (U.S. Pat.
514337), a lithium battery (manufactured by Matsushita Electric Co., Ltd.) using fluorinated graphite as a positive electrode active material, and a lithium battery (manufactured by Sanyo Electric Co., Ltd.) using manganese dioxide as a positive electrode active material are already commercially available.

In addition, batteries using sulfides, selenides, and tellurides of titanium, zirconium, hafnium, niobium, tantalum, and vanadium as positive electrode active materials (US Patent No. 4009
052 specification) and batteries using chromium oxide, niobium selenide, etc. [J, Ele, 1ctrochem
, SoclVol, 124, Xx7, pp. 968 and 3
25 (1977), etc. However, these batteries could not necessarily be said to be sufficient due to their battery characteristics. i The present invention has been made in view of the current situation, and its purpose is to miniaturize!
This means that we can provide a primary battery with excellent characteristics.

To summarize the present invention, in the primary battery of the present invention, the positive electrode active material is an oxide of a metal selected from the group consisting of ruthenium, rhodium, palladium, mono-osmium, iridium, and rhenium, and the negative electrode The active material is lithium, and the electrolyte material is chemically stable with respect to oxides of the metal and lithium, and is a substance that allows lithium ions to move for an electrochemical reaction with the oxide of the metal. It is characterized by: The terms positive electrode and negative electrode in this specification refer to a positive electrode and a negative electrode when configured as a battery, and in other documents, these may be expressed as a negative electrode and an anode, respectively.

When the above-mentioned metal oxides as the positive electrode active material in the present invention are used as a positive electrode, the positive electrode is prepared by forming a powder of these metal oxides or a mixture of the same and a binder powder into a film on a support such as nickel or copper. Pressure molding or mixing carbon powder to impart conductivity to these metal oxide powders,
It is formed by means K, such as placing this mixture in a metal container, or mixing the mixture with a binder solution, coating it on a support such as nickel or copper, and drying and forming it into a film.

Lithium, which is the negative electrode active material, is formed into a sheet like that of a general lithium battery, or the sheet is pressed onto a nickel or copper mesh to form the negative electrode. As an electrolyte, propylene carbonate, ethylene carbonate,
Aprotic organic solvents such as γ-butyrolactone, dimethylsulfoquinde, acetonitrile, formamide, dimethylformamide, nitromethane and LiCtO4, Li
Known electrolytes that are generally used in batteries that use lithium as a negative electrode active material can be used, such as combinations with lithium salts such as AtCt4, LiBF4, and Lict, or solid electrolytes or molten salts using Li+ as a conductor. .

Further, if necessary due to the battery structure, a diaphragm made of porous polypropylene or the like may be used.

Next, the present invention will be explained with reference to Examples, but the present invention is not limited to these in any way.

In the Examples, the battery was manufactured under a dry argon gas atmosphere. Example 1 FIG. 1 is a schematic cross-sectional view showing the configuration of a button-type battery that is a specific example of the present invention, in which 1 is a stainless steel container, 2 is a stainless steel container, and 2 is a stainless steel container.
is a lithium negative electrode, 2 is a porous polypropylene diaphragm, 4 is a lithium negative electrode,
5 indicates a felt made of carbon fiber, 5 indicates a positive electrode mixture, and 6 indicates a nylon packing.

A primary battery was manufactured using the battery configuration shown in the first drawing.
The diameter of the battery cell was 20WB, and the height was 4u. As the electrolytic solution, a 1 mol/t solution of dehydrated Licto4 dissolved in distilled dehydrated propylene carbonate was used, and was used by impregnating the diaphragm and the felt 4 made of carbon fiber.
The positive electrode mixture 5 consists of 0.5ff) Rh2O3 powder and 0.1t.
Acetylene black was formed by mixing with the above electrolyte. A lithium sheet was used as the lithium negative electrode 2 with a porous polypropylene diaphragm 3 in between. The open circuit voltage of the battery thus produced was 3.7V.

When constant current discharge was performed at 1 mA/d, the initial voltage was 3.
．． 35V, average electromotive force 1.7V until the voltage becomes 1V
Similarly, the discharge capacity was 101 Ahr/Kfl and the energy density was 170 WhrA.

FIG. 2 shows the discharge curve of the primary battery of this example. Possible reactions include, but if the valence of other Rh changes from 3 to 0
, 2→1, 2→0, 1→0.

Also, 2.55, 2.62V, 2.56V12.
It is difficult to distinguish reactions based only on EO as the voltage is close to 50V. However, the initial potential was about 3.3, (1
), (2) and other reactions that involve a change in the valence of Rh are unlikely to occur at the initial stage, and it is unlikely that a reaction involving a change in the valence of Rh occurs in the initial stage.
It is thought that a topochemical reaction of the following formula is occurring.
The initial voltage decreases linearly until about 3.5 hours.

These are probably considered to be an increase in internal resistance due to reaction products, and about 1 V decreases due to internal resistance. The flat part seen after 5 hours of discharge is about 1.4V, but if the internal resistance is taken into account, it will be about 2.4V, and here (1),
It is thought that a reaction corresponding to equation (2) etc. is occurring.

Assuming the reaction of equation (1), 5
The utilization rate will be 0%. , Example 2 As positive electrode mixture 5, 0.5ff) PdO powder and 0.1v
The primary battery shown in FIG. 1 was prepared in the same manner as in Example 1, except that the acetylene black was mixed with the same electrolyte as in Example 1.

The open circuit voltage of the battery thus produced was 3.35.

1mA/C! When constant current discharge was performed at 1t, the average electromotive force 1 until the initial voltage 2.6V1 voltage decreased to 1
．． 5V, discharge capacity 389Ahr/1cf, and energy density 690Whr/Kg.

FIG. 3 shows the discharge curve of the primary battery of this example. is possible.

In the structure of PdO, oxygen coordinates a block of Pd in a slightly distorted square, and the oxygen is surrounded by Rd in the form of a tetrahedron. The discharge curve becomes flat near 1.5V, and is significantly different from the theoretical electromotive force in equation (4).

When formula (8) is assumed, the utilization rate reaches 100% in 69.7 hours, and it can be said from experiments that RdO is an anode active material with a high utilization rate. As positive electrode mixture 5, 0.5ff)0s
The primary battery shown in FIG. 1 was produced in the same manner as in Example 1, except that 0.04 powder and 0.1 t of acetylene black were mixed and formed with the same electrolyte as in Example 1.

The open circuit voltage of the battery thus produced was 3.2V. When constant current discharge was carried out at 1 mA/Cd, the initial voltage was 2.9 V, the average electromotive force was 2.4 V until the voltage decreased to 1 V, and the discharge capacity was 19 Ahr/ICf, and the energy density was 46 Whr/Kg. The discharge curve of the example primary battery is shown in FIG.

As a reaction, there is 7 at the first flat part of the discharge.
It is thought that the reaction of formula is proceeding.

- The rate is very low, and the utilization rate is 3% after 2 hours of discharge, assuming equation (5). Example 4 Positive electrode mixture 5 and 0.5ff) Ir2O3 powder and 0.5ff)
The first step was carried out in the same manner as in Example 1, except that 1 t of acetylene black was mixed and formed with the same electrolyte as in Example 1.
The primary battery shown in the figure was manufactured.

The open circuit voltage of this battery was 3.95V. Also, 1mA
/c! When constant current discharge was performed in step 11, the initial voltage was 3.
, 6V, average electromotive force 2.1V until the voltage drops to 1,
Same discharge capacity 150Ahr/Kf, energy density 3
It was 40Whr/Kg. FIG. 5 shows the discharge curve of the secondary battery of this example. There is a reaction. However, this theoretical electromotive force EO is too small compared to the experimental value. Ir2
Although the structure of O3 is unknown, it is thought that in this case as well, a topochemical reaction occurs at the beginning of the discharge as shown in the following equation. Pipe number Ik number. Assuming the reaction of @-1P●tube^8, the discharge efficiency will be 5.0% in 29.6 hours.

Example 5 As a positive electrode mixture, 0.5ff) PtO2 powder and 0.1f
The primary battery shown in FIG. 1 was produced in the same manner as in Example 1, except that the acetylene black was mixed with the same electrolyte as in Example 1.

The circuit voltage of this battery was 3.35V.

When constant current discharge was performed at 1 mA/Cd, the initial voltage was 2.7 V, and the average electromotive force was 1.8 until the voltage decreased to 1 V.
Similarly, the discharge capacity was 333 Ahr/Kg, and the energy density was 670 Whr/ICII.

The discharge curve of the negative battery of this example is shown in the sixth tooth. The following reactions can be considered. 1JV2●VV!
Rod→ Judging from the electromotive force, it seems that the above reaction is occurring.

The utilization rate of PtO2 is large, and assuming the reaction of equation l,
The utilization rate is 75% after 56.4 hours of discharge. Example
6 As positive electrode mixture 5, 0.5rf) Re2O7 and 0.14
The primary battery shown in FIG. 1 was prepared in the same manner as in Example 1, except that the acetylene black of Example 1 was mixed with the same electrolyte as in Example 1.

The open circuit voltage of this battery was 4.1V. 1mA/Cd
When performing constant current discharge, the initial voltage was 4.0V, and until the voltage decreased to 1V, the average electromotive force was 2.9V, the discharge capacity was 58Ahr/Kg, and the energy density was 173Wh.
/Kf.

FIG. 7 shows the discharge curve of the primary battery of this example. As a reaction, this is considered, but the actual initial electromotive force is as large as about 4V.

This is probably due to a topochemical reaction occurring between Re2O7 and Li←. As is clear from the above description, the battery of the present invention has the advantage that it can be used in various fields as a small, high energy density battery with a large electromotive force and discharge capacity.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the structure of a button-type battery that is a specific example of the present invention. 2 to 7 are graphs showing discharge curves of primary batteries of Examples 1 to 6 of the present invention, respectively. 1...
・Stainless steel container, 2...Lithium negative electrode, 3
...Porous polypropylene diaphragm, 4 carbs,
Felt made of fiber, 5... Positive electrode mixture, 6.
...Nylon packing.

Claims (1)

[Claims] 1 The positive electrode active materials are ruthenium, rhodium, palladium,
It is an oxide of a metal selected from the group consisting of osmium, iridium, platinum, and rhenium, the negative electrode active material is lithium, and the electrolyte material is chemically stable with respect to the metal oxide and lithium and contains lithium ions. is a substance that moves to perform an electrochemical reaction with the oxide of the metal.