快离子导体助剂对石墨低温性能的影响  

Influence of fast ionic conductor additives on low temperature properties of graphite

作　　者：李纾黎 陈士朋 张伶俐 LI Shuli;CHEN Shipeng;ZHANG Lingli(Guangzhou Penghui Energy Technology Co.,Ltd.,Guangzhou Guangdong 511483,China)

机构地区：[1]广州鹏辉能源科技股份有限公司,广东广州511483

出　　处：《电源技术》2025年第4期720-726,共7页Chinese Journal of Power Sources

摘　　要：固态电解质界面(SEI)的Li^(+)脱溶剂化是制约锂离子电池快速充电和低温性能的关键步骤。通过液相包覆在石墨负极上分别设计了Li_(3)P、LiF、Li_(3)PO_(4)界面相,促进了Li+的脱溶剂化并构建了富无机SEI膜,从而加速了Li^(+)在电极界面和界面间的传输。由EIS阻抗可以明显发现,相比于常规石墨,添加助剂LiF后,低温内阻明显降低。使用PHG-Q阳极的电池可以在−20℃@0.2 C保证充电容量占比49.57%,在−40℃@0.2 C,与常规石墨充电容量占比提升7.29%。低温−40℃@0.05 C循环LiF助剂有利于Li^(+)脱溶剂化作用,循环800次容量保持率可以保持93.95%。Li^(+)de-solvation at the solid electrolyte interphase(SEI)is a critical step governing the fast charging and low-temperature performance of lithium-ion batteries.The Li_(3)P,LiF,and Li_(3)PO_(4) interfacial phases were designed on graphite anode by liquid-phase coating,respectively,which promoted the de-solvation of Li^(+)and constructed an inorganic-rich SEI membrane,thus accelerating the Li+transport at the electrode interfaces and between the interfaces.From the EIS impedance,it can be clearly found that the low-temperature internal resistance is significantly reduced with the addition of the additive LiF compared with conventional graphite.The battery using PHG-Q anode can guarantee 49.57%charging capacity share at-20℃@0.2 C.At-40℃@0.2 C,the charging capacity share is improved by 7.29%with conventional graphite.Cycling LiF additives at low temperature-40℃@0.05 C facilitates Li^(+)de-solvation effect,and the capacity retention rate can be maintained at 93.95%for 800 cycles.

关 键 词：锂离子电池 快离子导体助剂 低温性能 负极材料 

分 类 号：TM912[电气工程—电力电子与电力传动]