EMD热处理温度对锂锰电池放电性能的影响  

Effect of EMD heat treatment temperature on discharge performance of Li-MnO_(2) battery

作　　者：潘汉殿 李新周 余佑锋[1] 常海涛[1] PAN Han-dian;LI Xin-zhou;YU You-feng;CHANG Hai-tao(R&D Division,Fujian Nanping Nanfu Battery Co.,Ltd.,Nanping,Fujian 353000,China)

机构地区：[1]福建南平南孚电池有限公司研究开发部,福建南平353000

出　　处：《电池》2022年第4期433-436,共4页Battery Bimonthly

摘　　要：为优化电解二氧化锰(EMD)热处理工艺,提高二氧化锰(MnO_(2))作为锂-二氧化锰(锂锰)电池正极材料的整体性能,将EMD在340~420℃进行梯度烧结,并将烧结后的EMD制成锂锰电池,采用大电流、高截止电压放电条件进行放电。EMD样品在不同温度下烧结后,比容量、放电电压平台等发生了较大变化。锰含量及孔径数据分析表明,烧结温度为340~380℃时,杂质水的去除及孔径的增大降低了扩散电阻,提高了活性MnO_(2)含量,使电化学性能得到提升,比容量可达250.2 mAh/g(20 mA恒流放电5 s,静止55 s,循环放电至截止电压2.2 V);在400~420℃下烧结,由于反应生成的O_(2)溢出,降低了活性MnO_(2)含量,且BET比表面积降低导致电化学反应活性位点减少,样品的比容量降低,电化学性能变差。In order to optimize the electrolytic manganese dioxide(EMD)heat treatment process and improve the overall performance of manganese dioxide(MnO_(2))as cathode material of lithium-manganese dioxide(Li-MnO_(2))battery,EMD was gradient sintered in 340-420℃,the sintered EMD was made into Li-MnO_(2) battery,which was discharged under the condition of high current and high cut-off voltage.After the EMD samples were sintered at different temperatures,the specific capacity and discharge voltage platform had changed greatly.The manganese content and pore size data analysis indicated that the removal of impurity water and the increase of pore size at the sintering temperature of 340-380℃reduced the diffusion resistance and increased the active MnO_(2) content,which led to the improvement of the electrochemical performance,the specific capacity could reach 250.2 mAh/g(galvanostatic discharging for 5 s at 20 mA,standing for 55 s,cycle to cut-off voltage of 2.2 V).Sintering at 400-420℃,the active MnO_(2) content was reduced due to the overflow of O_(2) generated by the reaction,the reduction of the BET specific surface area reduced the active sites of the electrochemical reaction,which caused the specific capacity of sample to decrease and the electrochemical performance to deteriorate.

关 键 词：热处理 电解二氧化锰(EMD) 锂-二氧化锰(锂锰)电池 放电性能 烧结温度 

分 类 号：TM911.41[电气工程—电力电子与电力传动]