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 D50 of 1.92 fan, specific surface area of 11.4 m2/g,cathode surface density of 2.8 g/dm2 and conductive agent amount of 4.0% had better processing performance 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 smell 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.%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1.92 μm,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；5.00 C充电和15.00 C放电时的表面温升很小.在2.0～3.8 V充放电,优化后的20.00 C、30.00 C放电容量分别为1.00 C时的96.6％、86.1％,1.00C充电、10.00 C放电,第300次循环的容量保持率为86.3％.
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