JP3161310B2 - Battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a battery sealing material and a battery using the sealing material.

[0002]

2. Description of the Related Art In sealing a battery, an insulating sealing member such as nylon or polypropylene is disposed between a metal container which also functions as a positive electrode terminal and a negative electrode terminal, and the sealing member is pressed against the positive electrode and the negative electrode container. Prevents liquid leakage. In addition, in some types of battery systems, there are many electronic components that are used for a long time under severe environmental conditions as a power source for memory backup, and in such a battery system, the positive and negative electrodes containing power generation elements are used. There has been an attempt to interpose a sealing material having a pitch as a main component, as described in JP-A-56-57254, between a metal container and an insulating sealing body.

[0003]

The pitch-based sealing material has better adhesion to metal than other organic and inorganic sealing materials.
Alternatively, it is excellent for alkaline and acidic organic and inorganic electrolytes, but when the battery is used under severe environmental conditions for a long period of time, the initial excellence due to fluidization of the sealing material or deterioration due to the electrolyte solution The physical properties changed and were not sufficient. In addition, the water repellency of the electrolytic solution was not sufficient, and the resistance to the creeping characteristics peculiar to the alkaline electrolytic solution was poor.

[0004]

SUMMARY OF THE INVENTION In order to solve these problems, the present invention provides a method for sealing a carbon atom (C) between a positive / negative metal container accommodating a power generating element and an insulating sealing member.
And fluorine atom (F) having an atomic ratio F / C of 0.5 to 1.8.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The use of pitch fluoride having an atomic ratio F / C of carbon atom (C) to fluorine atom (F) of 0.5 to 1.8 is performed when the atomic ratio F / C is 0. If it is less than 0.5, the softening point of the fluorinated pitch becomes about 150 ° C., and the fluidity in a high-temperature atmosphere becomes high, which is not preferable. Atomic ratio F / C
Is more than 1.8, the property becomes a viscous liquid state, and the compatibility with other organic solvents deteriorates.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to a button-type zinc-air battery.

FIG. 1 is a longitudinal sectional view of a button-type zinc-air battery. In FIG. 1, reference numeral 1 denotes a negative electrode container made of a clad material in which a SUS material and a copper material having a thickness of 0.3 mm are bonded together, 2 denotes a negative electrode mixture made of zinc powder, 3 denotes an insulating sealing member made of 6.6 nylon, Is a separator made of a microporous film, 5 is an air electrode mainly composed of manganese oxide, 6 is a water-repellent film made of an unsintered fluororesin film, 7 is an air diffusion paper, and 8 is a 0.3 mm thick iron material. A positive electrode container 9 whose surface is subjected to corrosion-resistant nickel plating, and 9 is an air hole. As the electrolyte, a 35% solution of potassium hydroxide in which zinc oxide is dissolved is used.

[0008] PR44 (diameter: 11.4 mm, height: 5.4 mm) was constructed as a button-type zinc-air battery having the above configuration, and an evaluation test was performed.

First, a carbon atom (C) and a fluorine atom (F)
Of fluorinated pitch having an atomic ratio F / C of 0.7 to a fluorine-based dispersion solvent, in this case, a dichlorofluoroethane solution,
The dispersion dispersed in a concentration of weight% was applied to the joint of the negative electrode container, and then heat-treated at 90 ° C. for 1 hour, and applied to the joint of the negative electrode container. This was coupled with a sealing body to form a battery, which is referred to as a battery A. A conventional battery that does not perform any processing is referred to as a battery B. The batteries using a solution in which a pitch having a penetration of 20 was dissolved in toluene at a concentration of 30% by weight as a sealing material were designated as C, and these batteries A,
B and C were examined for the number of leaked liquids after storage for 6 weeks and 9 weeks in an environment at a temperature of 45 ° C. and a humidity of 90% RH. The number of samples was 50 in each case. Table 1 shows the results.

[0010]

[Table 1]

In another embodiment, a cylindrical manganese dioxide in which fluorinated lithium salt is used as an electrolyte in a mixed solvent of polypropylene carbonate and dimethoxyethane as an electrolytic solution, manganese dioxide is used in a positive electrode, and metallic lithium is used in a negative electrode. Lithium battery, CR123A (diameter 17m
m, height 34 mm, electric capacity 1300 mAh), using the same sealing material as A, B, C,
100 pieces of E and F were prepared at a temperature of 60 ° C. and a relative humidity of 9
The number of leaked liquids when stored in a 0% atmosphere for 1, 3, 6 months was examined. The number of samples was 50 in each case. Table 2 shows the results.

[0012]

[Table 2]

As can be seen from Tables 1 and 2, the batteries A and D using the pitch fluoride of the present invention have sufficient leakage resistance.

As an example, a pitch fluoride having an atomic ratio F / C of carbon atom (C) to fluorine atom (F) of 0.7 was used. Similar results are obtained when the atomic ratio F / C is 0.5 to 1.8. Further, as the dispersion solvent other than the examples as the dispersion solvent of the pitch fluoride, monofluorotrifluoromethane, monochlorodifluoromethane, trichlorotrifluoroethane, monochloropentafluoroethane, a single fluorinated solvent such as perfluoroalkylamine, or a mixture thereof was used. Anything can be used.

Such a fluorinated pitch can be obtained by fluorinating the pitch with a fluorine gas at a temperature lower than the softening point of the pitch, specifically at a temperature lower than 350 ° C. In this case, the pitch material is a petroleum distillation residue, a naphtha distillation residue, an isotropic pitch obtained by distilling petroleum or coal heavy oil such as coal tar, a mesophase pitch, a hydrogenated mesophase pitch, and a mesocarbon microbead.

[0016]

As described above, according to the present invention, the pitch resistance is significantly improved by interposing the fluoride fluoride between the positive and negative metal containers accommodating the power generating element and the insulating sealing body. It is to let. This is considered to be because the chemical resistance and environmental resistance of the pitch fluoride to the electrolytic solution are excellent, and the water repellency is much higher than that of the conventional sealing material. By the way, when comparing the contact angle with water as the above parameter for comparing the water repellency, polytetrafluoroethylene is 105 ° as a typical material having a high contact angle, while the pitch fluoride is in the range of 120 to 150 °. It is.
As described above, the pitch fluoride shows strong water repellency to the electrolytic solution and prevents leakage of the electrolytic solution.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a button-type zinc-air battery of the present invention.

[Explanation of symbols]

 Reference Signs List 1 negative electrode container 2 negative electrode mixture 3 insulating sealing member 4 separator 5 air electrode 6 water repellent film 7 air diffusion paper 8 positive electrode container 9 air hole 10 sealing material

Claims (3)

(57) [Claims] 1. A battery comprising a sealing material disposed between positive and negative metal containers accommodating a power generating element and an insulating sealing body,
A battery, wherein the sealing material is a pitch fluoride obtained by reacting the pitch with a fluorine gas. 2. The battery according to claim 1, wherein the pitch is any one of isotropic pitch, mesophase pitch, hydrogenated mesophase pitch, and mesocarbon microbeads. 3. The battery according to claim 1, wherein the atomic ratio F / C of carbon atoms (C) to fluorine atoms (F) of the fluorinated pitch is 0.5 to 1.8.