摘要
金属锂具有极高的理论容量(3 860 mAh/g)与极低的还原电位(-3.04 V),作为负极材料将使电池能量密度大大提升,有望实现大于400 Wh/kg的目标,并使新能源汽车续航里程大大延长。然而,金属锂负极与电解液的不断反应在消耗电解液的同时,亦会增大电池内阻。在实验中,采用添加人工固体电解质膜的方法,在抑制金属锂与电解液反应的同时,氮化锂的高离子电导率亦能实现金属锂表面的锂离子的快速传输,使电池具有较低的内阻。得益于氮化锂固体电解质膜的缓冲作用,所组装的锂/锂对称电池可在0.4 mA/cm~2电流密度下稳定循环1 000 h,临界电流密度达到1.8 mA/cm~2;钴酸锂/金属锂软包半电池1 C条件下循环300圈后,容量保持率可达93.1%。
Possessing a super high theoretical capacity(3 860 mAh/g) and an ultra-low reduction potential(-3.04 V), metal lithium is promising anode for present secondary batteries, leading to much higher energy density, achieving the aim of over 400 Wh/kg and prolonging the endurance for new energy vehicle. However, the continuous reaction between the lithium anode and electrolyte consumes the electrolyte and also increases the impedance of the battery. In this study, the artificial solid-state interphase to inhibit the reaction between lithium metal and electrolyte were integrated. The high ion conductivity of lithium nitride can also achieve the fast transfer of lithium ions on the surface of lithium metal, thus lowing the impedance of the battery. Due to the buffer layer of the lithium nitride solid-state interphase, the assembled lithium/lithium symmetric battery is able to cycle for 1 000 h at a current density of 0.4 mA/cm~2, and with a critical current density of 1.8 mA/cm~2. After300 cycles at 1 C, the capacity retention rate of the lithium cobalt/lithium metal pouch half battery is as high as93.1%.
作者
彭亮
赵明
PENG Liang;ZHAO Ming(College of Automotive Engineering,Shanxi Vocational University of Engineering Science and Technology,Jinzhong 030600,China;Tianeng Battery Group Co.LTD,Huzhou 313100,China)
出处
《粉末冶金工业》
CAS
北大核心
2023年第6期94-100,共7页
Powder Metallurgy Industry
基金
浙江省重点研发计划资助项目(2020A01006)。
关键词
金属锂负极
人工固体电解质膜
氮化锂
离子电导率
电解液
lithium anode
artificial solid-state interphase
lithium nitride
ionic conductivity
electrolyte
