JPS60186551A - Electrically-conductive composite material - Google Patents

Abstract

PURPOSE:A composite material useful as an electrode having corrosion resistance to electrolyte, dispersion resistance to electrolyte, and permeability resistance to electrolyte, obtained by blending a mixture consisting of high-density polyethylene, carbon black and graphite with a high polymer compound having ability to adsorb an electrolyte. CONSTITUTION:A mixture consisting of high-density polyethylene and carbon black or high-density polyethylene, carbon black and graphite is blended with a polymer to provide and ion or a molecule as a dopant in an electrolyte. A polymer selected from trans-polyacetylene, cis-polyacetylene, poly(para-phenylene), poly(meta-phenylene), poly(para-phenylenevinylene), and poly(para-phenylene oxide) is used as the polymer, and an amount of it used is an amount to give a ratio to the high-density polyethylene of 4.8-1.6(by weight).

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a conductive composite material that has improved corrosion resistance and electrical conductivity against an electrolytic solution, as well as improved diffusion resistance and permeation resistance of the electrolytic solution.

[Technical background]

Conductive composite materials made by dispersing conductive carbon particles such as carbon black (CB), Grapheye (Gr), fine metal powder, or short fibers in resin can be produced relatively easily. can be imparted with conductivity;
It has good moldability, excellent properties such as corrosion resistance, light weight, and chemical resistance, and it is also possible to control conductivity. It can be used in a wide variety of applications, such as electrostatic and antistatic materials, various resistors, battery electrode materials, and plating materials.

From the viewpoint of energy saving and effective use of resources, the emergence of batteries that can extract large amounts of power is desired.
As development efforts progress, carbon-plastic conductive composite materials (carbon/ Studies on polymer-based conductive composite materials are progressing further. This method not only has high electrical conductivity of the material, but also has insufficient corrosion resistance against the electrolyte, and also has the disadvantage that the ITM liquid permeates through the electrode plate, resulting in a decrease in energy efficiency during long-term use of the battery. Furthermore, it has been desired to reduce the liquid diffusivity of conductive materials.

[Purpose of the invention]

The present invention provides a conductive composite material capable of fully meeting the various demands described above, particularly a conductive composite material with improved corrosion resistance and permeation resistance against electrolytes. The purpose is to

[Summary of the invention]

Hereinafter, a description will be given using a plastic electrode as an application example of the conductive composite material.

Plastic I1. As the material used to improve the conductivity of the electrode, at least one fence selected from the group of carbon blank (CB), carbon fiber, carbon cloth, graphite (Gr) powder, etc. is used. .

When using these conductivity imparting materials, e.g.
In the case of powder like Pon black, the surface area is 9
Preferable results can be obtained by using particles with an average particle diameter of about 00'/ or more, and in the case of graphite, about 10 #tn or less.

Further, as the electrode body, high-density polyethylene (hereinafter abbreviated as HDPE) is particularly used among polyolefins which have good acid resistance, are available at low cost, and have excellent processability.

The present invention is characterized in that, in addition to these blending components, a polymer compound having an electrolyte adsorption function is used in combination to reduce the diffusion of the electrolyte.

Since the molecules or ions in the electrolyte are considered to be electron-accepting dopants, in this case a sufficient initial effect can be obtained by using a substance with adsorption ability.

Polymers used for this purpose include trans-polyacetylene, cis-polyacetylene, poly(para-phenylene), poly(methane-phenylene), HoIJ (hala-phenylene vinylene), and poly(hala-phenylene sulfide). , poly(meta-phenylene sulfide), poly(para-phenylene oxide), etc.

The following table shows the molar ratio of the dopant to the polymer (molar ratio to the polymer and its electrical conductivity (λ)) when ASF, which is a typical dopant material, is used.

In addition, let's assume that the dopant is 7, and this is brNa.
lK etc. can be used.

As can be clearly seen from the table, even though there are differences in the degree of dopant concentration depending on the type of polymer, it is found that it is possible to maintain a considerable degree of dopant concentration in any of the polymers.

The proportions (perforation) of each component in the conductive composite material formed according to the present invention are as follows.

High density polyethylene 45-50%, carbon black 1
0-25 zigura 7ite 0-64 thi, polymer 5-50
It is Chi.

[Embodiments of the invention]

Using poly(paraphenylene sulfite) (abbreviated as PPS), which has a high electrolyte adsorption capacity, that is, a high dopant concentration, a test piece was prepared with the formulation shown in the table below, and the introduction rate (λ
) and the amount of electrolyte permeation (D) after 200 hours in song 1.
A table of results was obtained.

The molding conditions for making the test C were as follows: Each composition was heated to 200°C and placed in a 1 ton pressure kneader.
After kneading for about 60 minutes, a sheet was formed using a press molding machine at 200°C. (In case of sheeting by roll 15
It was prepared at 0°C. )Also? ! , f, %l'7 The measurement of the amount of liquid permeation was carried out using an apparatus as shown in FIG.

In Fig. 1, 1 is a test piece with a constant value of -11≠well, and the liquid mill contact area is 20 cm in diameter and 1 in thickness. 6-layer bromine-free electrolyte 7
(ZnBr25 mat/aqueous solution) is a bromine-free electrolytic container containing 25-, 4 is a bromine-containing electrolyte 6 (
ZnBr23 mol/l + Br2' 5mot/
2 is a bank, 5Fi tightening bolt, and 8Fi electrolyte evaporation prevention lid.

Next, in order to carry out actual determination using this measuring device, first place the test piece 1 into a bromine-free defroster solution container 6, place the backing 2, and then tighten the bromine-containing electrolyte solution container 4 with bolts 5.
Tighten so that there is no leakage. Bromine-containing electrolyte with
6 and bromine-free electrolyte 7 at the same level (eliminate water head difference)
After a certain period of time, the amount of bromine Br2 in the bromine-containing electrolyte 6 that has penetrated and diffused into the bromine-free electrolyte is determined by iodometric titration.

〔Effect of the invention〕

The conductive composite material constructed according to the present invention can reduce the amount of diffusion of the electrolyte because it contains a polymer that is a dopant for ions or molecules in the electrolyte. It is stable and can be used for a long period of time when used as such.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of 'tJL solution solution diffusion solution diffusion 6111. 1... 11 constant samples, 6... bromine-free powder liquid container, 4... liquid containing electrolyte liquid container. Agent - YP Physician Sanro Kiyoshi Figure 1 19 Car fl display % original [J 1977. '41935 Conductive Composite Material)', Eve) 1, l, , (610) Meidensha Co., Ltd. 4,
Agent (1) Amend "(λ)" in page 7, line 5 of the specification to "(c)".

Claims (1)

[Claims] 1. A compound consisting of high-density polyethylene and carbon black or high-density polyethylene, carbon black and graphite is characterized by adding and mixing a polymer for doping ions or molecules in liquid M. 2. Trans-polyacetylene, cis-polyacetylene, poly(para-phenylene), poly(meta-phenylene), poly(hala-phenylenevinylene), poly(rose-phenylene),
phenylene oxide) as a dopant polymer;
[J, l/Jl Derivation of the first clay description] ゛sexual compound Paulowniaceae. 6. The compounding ratio of the dopant polymer to the high-density polyethylene is 4.8 to 1.6, with a heavy weight of 4.8 to 1.6. The conductive composite material described in Tll'1.