LiFePO_4锂离子电池的高倍率充放电性能  

High rate charge-discharge performance of LiFePO_4 Li-ion battery

作　　者：钟海江[1,2] 唐有根[1] 卢周广[1] 张军 

机构地区：[1]中南大学化学化工学院,湖南长沙410083 [2]湖南格林新能源有限公司,湖南湘潭411101

出　　处：《电池》2012年第3期142-145,共4页Battery Bimonthly

基　　金：国家自然科学基金(21001117)

摘　　要：研究了正极材料、正极面密度、导电剂含量及电极结构对18650型LiFePO4锂离子电池高倍率充放电性能的影响。当D50为1.92μm,比表面积为11.4 m2/g,正极面密度为2.8 g/dm2,导电剂含量为4.0%时,电池具有较好的加工性能和倍率性能。相比于单极耳结构,双极耳结构电池的内阻减小了50%,为14 mΩ左右,且分布集中;5.00C充电和15.00C放电时的表面温升很小。在2.0～3.8 V充放电,优化后的20.00C、30.00C放电容量分别为1.00C时的96.6%、86.1%,1.00C充电、10.00C放电,第300次循环的容量保持率为86.3%。The effects of cathode materials, cathode surface density, conductive agent amount and electrode structure on high rate charge-discharge performance of 18650 type LiFePO4 Li-ion battery were studied. The battery with the Ds0 of 1.92 μm, specific surface area of 11.4 m2/g, cathode surface density of 2.8 g/dm^2 and conductive agent amount of 4.0% had better processing per- formance and rate capability probably. The internal resistance of battery with the structure of bipolar reduced 50% to about 14 mΩ compared to the structure of unipolar,its distribution was centralized, the surface temperature rise was very small under the charge at 5. 00 C and discharge at 15.00 C. After optimization, when charged-discharged in 2.0 - 3.8 V, the discharge capacity at 20. 00 C and 30.00 C was 96.6%, 86.1% of that at 1.00 C rate, respectively, the capacity retention rate was 86.3% at the 300th cycle of 1.00 C charge and 10.00 C discharge.

关 键 词：磷酸铁锂(LiFePO4) 锂离子电池 高倍率 充放电性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]