Thermal behavior of overcharged Ni/MH battery is studied with microcalorimeter. The battery is in-stalled in a special device in a microcalorimeter with a quartz frequency thermometer. Quantity of heat and heat capaci...Thermal behavior of overcharged Ni/MH battery is studied with microcalorimeter. The battery is in-stalled in a special device in a microcalorimeter with a quartz frequency thermometer. Quantity of heat and heat capacity of the battery charged at different state of charge (SOC) at different rates are meas-ured by the microcalorimeter. Based on a series of assumputions, heat transfer equation is set up. Ex-pression of heat generation is attained by curve fitting instead of theoretical calculation. Thermal model is used to simulate thermal behavior of the battery in charging period , results of calculation and ex-periment match very well. The temperature distribution is non-uniform because the poor conductivity limits the heat transfer during charging process. It is difficult to greatly improve the heat conductivity of the battery because it is related to materials inside the battery including electrodes, separators and so on. Therefore, high rate charge should be avoided in actual use. It may cause some damage to the battery.展开更多
基金Supported by the National Key Basic Research and Development Program of China (Grant No. 2002CB211800)
文摘Thermal behavior of overcharged Ni/MH battery is studied with microcalorimeter. The battery is in-stalled in a special device in a microcalorimeter with a quartz frequency thermometer. Quantity of heat and heat capacity of the battery charged at different state of charge (SOC) at different rates are meas-ured by the microcalorimeter. Based on a series of assumputions, heat transfer equation is set up. Ex-pression of heat generation is attained by curve fitting instead of theoretical calculation. Thermal model is used to simulate thermal behavior of the battery in charging period , results of calculation and ex-periment match very well. The temperature distribution is non-uniform because the poor conductivity limits the heat transfer during charging process. It is difficult to greatly improve the heat conductivity of the battery because it is related to materials inside the battery including electrodes, separators and so on. Therefore, high rate charge should be avoided in actual use. It may cause some damage to the battery.
