JPS6155745B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a non-aqueous electrolyte battery using a metal oxide as a positive electrode active material, and particularly relates to a method for manufacturing a positive electrode. Various materials have already been proposed as positive electrode active materials for this type of battery, but metal oxides are particularly stable;
Moreover, it is considered to be a promising method because of its ease of handling. However, a single component of metal oxide cannot sufficiently satisfy both discharge capacity and operating voltage, and as an improvement method, the present inventors developed a two-component compound of metal oxide and vanadium pentoxide as a positive electrode. It has already been proposed to use it as an active material. The present invention is a positive electrode active material made of the above two-component compound that is further improved. That is, although the above-mentioned two-component compound can improve discharge capacity and operating voltage, it is not satisfactory in terms of uniformity of discharge voltage. Therefore, as a result of studies, the flatness of the discharge voltage is improved by using a three-component compound obtained by adding tungsten trioxide to the above-mentioned two-component compound as the positive electrode active material. Examples thereof will be described below. Example 1 For the positive electrode, 160 g of cupric oxide (CuO), 180 g of vanadium pentoxide (V ₂ O ₅ ), and 130 g of tungsten trioxide (WO ₃ ) were mixed in a mortar, and the mixture was heated in an electric furnace. Bake at 800℃ for 5 hours. Through this firing, various compounds are produced according to the reaction formula shown below, and a fired product containing a mixture of these compounds is obtained. 2CuO＋V ₂ O ₅ →Cu ₂ V ₂ O ₇ … CuO＋WO ₃ →CuWO ₄ … 10V ₂ O ₅ ＋12WO ₃ →4W ₃ V ₅ O ₂₀ +3O ₂ … Then, this fired product was crushed, and carbon powder was added to 80 g of powder after 200 mesh passes. 15 g and 5 g of fluororesin were added and mixed, and the mixture was pressure-molded at a pressure of 2.5 ton/cm ² to an outer diameter of 20 mm and a thickness of 1.3 mm, followed by heat treatment at 300°C. The negative electrode was a rolled lithium plate punched into a predetermined shape, and the electrolyte was prepared by dissolving 1 molar concentration of lithium perchlorate in a mixed solvent of propylene carbonate and 1.2 dimethoxyethane in an equal volume ratio. Create battery A with a diameter of 24.5 mm and a height of 2.8 mm. For comparison, cupric oxide (CuO)
A battery A′ using a vanadium pentoxide (V ₂ O ₅ )-based positive electrode active material was created. Example 2 Composition of positive electrode active material: 290 g of molybdenum trioxide (M ₀ O ₃ ), 180 g of vanadium pentoxide [V ₂ O ₅ )
g, using 230 g of tungsten trioxide (WO ₃ ),
These three components were mixed in a mortar, and the mixture was fired at 800° C. for 5 hours in an electric furnace. Through this firing, various compounds are produced according to the reaction formula shown below, and a fired product containing these compounds is obtained. 10V ₂ O ₅ +12WO ₃ →4W ₃ V ₅ O ₂₀ +3O ₂ … 3M ₀ O ₃ +2WO ₃ →5MO ₀ . ₆ W ₀ . ₄ O ₃ … M ₀ O ₃ +V ₂ O ₅ →M ₀ V ₂ O ₈ … Next, after pulverizing this fired product, Battery B was produced in the same manner as in Example 1. For comparison, a battery B' was prepared using a molybdenum trioxide (M ₀ O ₃ )-vanadium pentoxide (V ₂ O ₅ ) positive electrode active material. The figure shows the 1KΩ constant resistance discharge characteristics of these batteries, and from this characteristic diagram, A and B of the batteries of the present invention are shown.
It can be seen that the discharge curve of the battery has improved flatness and operating voltage compared to batteries A' and B' which use a binary compound of metal oxide and vanadium pentoxide as the positive electrode active material. In addition, Tables 1 and 2 show the flatness of discharge capacity and discharge pressure when changing the mixing ratio in each ternary system. ) - Vanadium pentoxide (V ₂ O ₅ ) - Tungsten trioxide (WO ₃ ) is excellent at a mixing ratio of 0.2 to 1.0 mol of V ₂ O ₅ and 0.1 to 0.5 mol of WO ₃ to 1 mol of CuO. Also, from Table 2, in the case of molybdenum trioxide (M ₀ O ₃ )-vanadium pentoxide (V ₂ O ₅ )-tungsten trioxide (WO ₃ ),
For ₃₁ mol of M ₀ O, V ₂ O ₅ is 0.2 to 1.0 mol, and WO ₃ is
It can be seen that excellent properties are exhibited at a mixing ratio of 0.2 to 1.0 mol.

【table】

【table】

[Table] Note that when a mixture of the three-component system of the present invention is simply mixed without firing, the characteristics of the flatness of the discharge voltage may not be satisfactory due to the influence of the inherent potential of each component. I couldn't get it. As described above, the method for producing a positive electrode according to the present invention involves mixing the three components of cupric oxide or molybdenum trioxide, vanadium pentoxide, and tungsten trioxide as positive electrode active materials (preferably 1 mol of cupric oxide). The mixing ratio is 0.2 to 1.0 mole of vanadium pentoxide and 0.1 to 0.5 mole of tungsten trioxide, or 0.2 to 1.0 mole of vanadium pentoxide and 0.2 to 0.2 mole of tungsten trioxide to 1 mole of molybdenum trioxide.
1.0 mol of the mixture (mixing ratio of 1.0 mol), and using a fired mixture, it is possible to improve the discharge capacity and operating voltage of a non-aqueous electrolyte battery, and also to improve the flatness of the discharge pressure. There is, and its industrial value is extremely large.

[Brief explanation of the drawing]

The drawing is a discharge characteristic diagram of a battery of the present invention using a positive electrode made of a ternary compound of metal oxide, vanadium pentoxide, and tungsten trioxide.

Claims (1)

[Claims] 1. A method for producing a positive electrode for a non-aqueous electrolyte battery, in which the three components of cupric oxide or molybdenum trioxide, vanadium pentoxide, and tungsten trioxide are mixed and the mixture is fired and used as an active material.