NiCl_(2)作为添加剂对热电池NiF_(2)正极材料倍率性能的影响

Effect of NiCl_(2)as additive on the rate capability of NiF_(2)cathode material in thermal battery

与硫化物相比,氟化物作为热电池正极材料,具有较高的理论放电电压和放电比容量。其中,NiF_(2)正极材料的理论放电电压为2.96 V,理论放电比容量为554 mAh/g。然而,由于NiF_(2)本征的离子电导率较低,导致其作为热电池正极材料时倍率性能较差,在1 A/cm^(2)电流密度下出现明显的容量衰减现象;另外,NiF_(2)的实际放电电压也远低于理论值。NiCl2正极材料的倍率性能较为优异,将其作为添加剂与NiF_(2)正极材料进行复合,可以显著改善NiF_(2)正极材料在大电流密度下的极化现象,延长热电池的放电时间。

Compared with sulfide,fluoride as cathode material for thermal battery,possessing high theoretical discharge voltage and specific discharge capacity.Among them,the theoretical discharge voltage of NiF_(2)cathode material is 2.96 V,and the specific discharge capacity is 554 mAh/g.However,due to the low intrinsic conductivity of NiF_(2),the rate capability is poor,and the capacity attenuation phenomenon appears obviously at the current density of 1A/cm^(2);in addition,the actual discharge voltage of NiF_(2)is much lower than the theoretical value.NiCl2 cathode material has excellent rate per‐formance,when it is combined with NiF_(2)as additive,the polarization phenomenon of NiF_(2)can be sig‐nificantly improved under high current density,and the discharge time of thermal battery can be pro‐longed.