热处理对电解二氧化锰阴极性能的影响

THE EFFECT OF HEATING TREATMENT ON PERFORMANCE OF ELECTROLYTIC MANGANESE DIOXIDE CATHODE

经不同温度处理的电解MnO_2具有不同的电性能.当处理温度等于(或低于)100℃时,MnO_2与Zn组成的碱性电池开路电压和工作电压(在电流强度为77～308μA/cm^2时放电)几乎不变,但放电曲线较陡.当处理温度等于(或高于)200℃时,电池的上述电压均随处理温度的上升而逐渐下降,但放电曲线较平坦,且随放电深度增加,极化变化较大.处理温度200℃为电性能的转交温度.在不同的处理温度中,以经200℃处理过的电解MnO_2的放电容量为最大.这些电性能的变化与电解MnO_2的吸附水和晶型变化有关.

The electrolytic manganese dioxide(EMD)has different electric performances through treatment with different temperatures, when the treating temperature is equal or lower than 100℃, the open circuit voltage(OCV) and the operating voltage(OV) of the alkaline batteries consisting of Zn anode are nearly unchanged and their discharging curves are steep. When the treating temperature is equal or higher than 200℃, their OCV and OV are lower than above mentioned values, they are decline with temperature rising, and their discharging curves are not steep. The shifts of the potential of reducing peaks are consistent with the variances of OCV and OV. 200℃ is the transforming temperature of its performance. The capacity of EMD treated with 200℃ is the largest. These electric performance may have relations to the absorbed water and the crystalline changes of EMD.