JPS58111275A - Organic electrolyte secondary battery - Google Patents

Abstract

PURPOSE:To improve conductivity to lower voltage in an initial stage of charge and enable to charge at constant current by mixing a conductive mass to polyacethylene which forms positive and negative eledctrodes. CONSTITUTION:90pts.wt. polyacethylene powder and 10pts.wt. graphite of a conductive mass are mixed and compressed to form a positive electrode and a negative electrode. These electrodes are combined with an organic eledtrolyte prepared by dissolving lithium perchlorete in an equal volume mixture solvent of polypropylene carbonate and 1, 2 dimethoxy ethane to form a secondary battery. Therefore, when the battery is charged, part of lithium ion is doped in graphite, and this lithium ion is used in discharge. Thereby conductivity is increased to lower voltage in an initial stage of charge and enable to charge at constant current.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an organic electrolyte secondary battery. Generally, this type of battery has a negative electrode made of a light metal such as lithium or sodium, and an organic solvent such as propylene carbonate or γ-butyl lactone. Lithium chlorate (btcloa)
), an organic electrolyte in which a solute such as lithium difluorosulfide (LiBF4) is dissolved, and a positive electrode containing molybdenum trioxide, vanadium pentoxide, etc. as an active material.

In recent years, for example, Japanese Patent Application Laid-Open No. 56-13646
9, a new secondary battery has been proposed in which the positive and negative electrodes are composed of polyacetylene and lithium perchlorate is used as the solute. Polyacetylene ((CH)χ) itself is 10-'
It has an electrical conductivity of Ω-1.3-1 to 100.1; however, when doping with ionic species,
The electrical conduction fr! 10. The charge/discharge reaction mechanism of this battery is expressed by the following equation.The problem with this battery is that the polyacetylene before doping with ion species T Because of its low electrical conductivity, the battery voltage at the beginning of charging is high (
(See Figure IIE1), it is difficult to charge the current, and the organic solvent is decomposed (usually the decomposition voltage is about 5.0V), which leads to problems.

The present invention has been made to solve the above problems,
The gist of this is to tag the positive and negative electrodes with polyacetylene that can be mixed with a conductive agent to improve electrical conductivity.

Examples of the present invention will be described in detail below. Example 1 A mixture of 90 parts by weight of polyacetylene powder and 10 parts by weight of graphite as a conductive agent was pressure molded. Positive and negative electrodes were used. Organic electrolyte was Lithium perchlorate is dissolved in a mixed solvent of equal volumes of 1a carbonate and 1.2 dimethoxyethane, and the separate part is made using a polypropylene non-woven tube with a diameter of 24cm and a height of 5°. battery (A)t-
Created Example 2 In Example 1, when copper powder is used as the conductive agent,
Except for this, the battery was otherwise the same as in Example 1 (Illt was prepared by a friend@).For comparison purposes, a comparative cell Ak (C) was prepared using positive and negative electrodes composed of polyacetylene alone without the conductive agent tS.

These batteries were charged with a photoelectric current of 1L 2 mA for 20 hours and discharged with a discharge current of fi 2 mm. Fig. 1 shows a charging characteristic diagram, and Fig. 2 shows a discharging characteristic diagram.

Figure 1 19 In the battery (C) used, the battery voltage is high at the initial stage of charging, and the voltage charging must be carried out only in the initial stage, and the decomposition voltage of the normal aSS medium ( On the other hand, in the battery of the present invention (~(S), the electrical type conductivity of the positive and negative electrodes is improved. Also, referring to Figure 2, it can be seen that the capacity increases when graphite is used as a conductive agent.This is because graphite is an intercalation compound, so some of the L
Graphite is doped with l ions or ClO4 ions, and this L1 ion or C4r)a ion is also utilized for discharge.

In addition to the lithium perchlorate shown in the examples, lithium borofluoride (1, IB
F4), lithium phosphorus hexafluoride (LiPF4), lithium phosphorus hexafluoride (Liloa4), lithium aluminum tetrachloride (Limu1cla), etc. can also be used. As detailed above, the present invention can be applied to polyacetylene. This relates to an organic electrolyte secondary battery with positive and negative electrodes, and combining polyacetylene with a conductive agent tS improves electrical conduction ft, suppresses the battery voltage at the initial stage of charging by 1it, and makes foot-shaped I51 photoelectricity possible. In addition, if graphite is used as a conductive agent, it is possible to increase the battery capacity in addition to the above effects, which greatly contributes to the performance of this type of battery. It is.

[Brief explanation of the drawing]

Figure II is a comparison diagram of the characteristics of the present invention battery and the comparative battery. Figure 1!11 shows the charging characteristics, and Figure II2 shows the discharge characteristics. )... Comparative battery 0 Applicant Sanyo Electric Co., Ltd. Kinsha

Claims (1)

[Scope of Claim] An organic electrolyte secondary battery characterized in that the pressure negative electrode is composed of polyacetylene mixed with a conductive agent. (2) The organic electrolyte secondary battery according to claim (1), characterized in that the conductive agent is graphite.