电力储能用磷酸锰铁锂锂离子电池的性能  

Performance of LiMn_(x)Fe_(1-x)PO_(4)Li-ion battery for grid energy storage

作　　者：郑建明 ZHENG Jianming(Xiamen Key Laboratory of Lithium Battery Energy Storage Application Materials and Safety,Xiamen Hithium Energy Storage Technology Co.,Ltd.,Xiamen 361000,Fujian,China)

机构地区：[1]厦门海辰储能科技股份有限公司,厦门市锂电池储能应用材料与安全重点实验室,福建厦门361000

出　　处：《电池》2025年第1期92-98,共7页Battery Bimonthly

基　　金：2023年厦门市重大科技项目(未来产业领域)(3502Z20231057)。

摘　　要：磷酸锰铁锂(LiMn_(x)Fe_(1-x)PO_(4))相比磷酸铁锂(LiFePO_(4)),具有更高的电压平台和能量密度,但在储能应用场景的研究还不够充分。研究LiMn_(x)Fe_(1-x)PO_(4)(x=0.4、0.5和0.6)与LiFePO_(4)正极材料在电力储能应用场景下的性能差异。随着Mn比例的增加,LiMn_(x)Fe_(1-x)PO_(4)电池的内阻增大,倍率充电性能降低,放电容量降低。在0.50 P恒功率模式下,相比LiFePO_(4)(2.50~3.65 V),LiMn0.4Fe0.6PO_(4)(2.50~4.30 V)的容量损失可达到17.8%。x=0.4、0.5和0.6时,LiMn_(x)Fe_(1-x)PO_(4)的能量效率分别为95.3%、95.1%和94.8%,低于LiFePO_(4)的96.2%。在45℃、1.00 P的条件下,经过950次循环后,LiMn_(0.6)Fe_(0.4)PO_(4)电池容量保持率较LiFePO_(4)降低约1.7个百分点。电池拆解分析表明,Fe/Mn元素溶解沉积到石墨负极,加速活性Li+的消耗。Compared with lithium iron phosphate(LiFePO_(4)),lithium iron manganese phosphate(LiMn_(x)Fe_(1-x)PO_(4))has a higher voltage platform and energy density,however it is not well investigated for energy storage application scenarios.The performance difference of LiMn_(x)Fe_(1-x)PO_(4)(x=0.4,0.5,0.6)and LiFePO_(4)cathode materials in grid energy storage application is studied.As the ratio of Mn increases,the resistance of LiMn_(x)Fe_(1-x)PO_(4)battery increases,the charge rate capability declines and discharge capacity decreases.At a constant power mode of 0.50 P,in comparison with LiFePO_(4)(2.50-3.65 V),the capacity loss of LiMn_(0.4)Fe_(0.6)PO_(4)(2.50-4.30 V)is 17.8%.When x is 0.4,0.5 and 0.6,the energy efficiencies of LiMn_(x)Fe_(1-x)PO_(4)are 95.3%,95.1%and 94.8%,respectively,which is lower than that(96.2%)of LiFePO_(4).After 950 cycles at the condition of 45℃with 1.00 P,the capacity retention of LiMn_(0.6)Fe_(0.4)PO_(4)battery is about 1.7 percentage points lower than that of LiFePO_(4).The disassembled batteries further show that Fe and Mn elements dissolve and deposit on graphite anode,which accelerates the active Li+consumption.

关 键 词：锂离子电池 正极材料 磷酸锰铁锂(LiMn_(x)Fe_(1-x)PO_(4)) 锰铁比 储能电池 电力储能 恒功率 

分 类 号：TM912.9[电气工程—电力电子与电力传动] TD98[矿业工程—选矿]