Cai Wenlong, Yan Chong, Yao Yu-Xing, Xu Lei, Chen Xiao-Ru, Huang Jia-Qi, Zhang Qiang
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing, 100081, China.
Angew Chem Int Ed Engl. 2021 Jun 1;60(23):13007-13012. doi: 10.1002/anie.202102593. Epub 2021 May 5.
Uncontrolled Li plating in graphite electrodes endangers battery life and safety, driving tremendous efforts aiming to eliminate Li plating. Herein we systematically investigate the boundary of Li plating in graphite electrode for safe lithium-ion batteries. The cell exhibits superior safety performance than that with Li dendrites by defining the endurable amount of uniform Li plating in graphite anode. The presence of "dead Li" can be eliminated owing to the uniform distribution of Li plating, and the average Coulombic efficiency for deposited Li during reversible plating/stripping process is decoupled as high as about 99.5 %. Attributing to the limited Li plating with superior Coulombic efficiency, the LiNi Mn Co O | graphite cell achieves a high capacity retention of 80.2 % over 500 cycles. This work sheds a different light on further improving the fast-charging capability, low-temperature performance, and energy density of practical lithium-ion batteries.
石墨电极中不受控制的锂金属沉积会危及电池寿命和安全,促使人们为消除锂金属沉积付出巨大努力。在此,我们系统地研究了用于安全锂离子电池的石墨电极中锂金属沉积的边界。通过定义石墨阳极中可承受的均匀锂金属沉积量,该电池展现出比有锂枝晶的电池更优越的安全性能。由于锂金属沉积的均匀分布,“死锂”的存在得以消除,并且在可逆沉积/剥离过程中,沉积锂的平均库仑效率解耦高达约99.5%。得益于具有卓越库仑效率的有限锂金属沉积,LiNiMnCoO|石墨电池在500次循环中实现了80.2%的高容量保持率。这项工作为进一步提高实用锂离子电池的快充能力、低温性能和能量密度提供了新的思路。