National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, and Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin, 150080, China.
MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150080, China.
Angew Chem Int Ed Engl. 2023 Jun 5;62(23):e202301073. doi: 10.1002/anie.202301073. Epub 2023 Apr 26.
Without excess Li, anode-free Li-metal batteries (AFLMBs) have been proposed as the most likely solution to realizing highly-safe and cost-effective Li-metal batteries. Nevertheless, short cyclic life puzzles conventional AFLMBs due to anodic dead Li accumulation with a local current concentration induced by irreversible electrolyte depletion, insufficient active Li reservoir and slow Li transfer at the solid electrolyte interphase (SEI). Herein, SrI is introduced into carbon paper (CP) current collector to effectively suppress dead Li through synergistic mechanisms including reversible I /I redox reaction to reactivate dead Li, dielectric SEI surface with SrF and LiF to prevent electrolyte decomposition and highly ionic conductive (3.488 mS cm ) inner layer of SEI with abundant LiI to enable efficient Li transfer inside. With the SrI -modified current collector, the NCM532/CP cell delivers unprecedented cyclic performances with a capacity of 129.2 mAh g after 200 cycles.
无过量锂的情况下，无负极锂金属电池（AFLMB）被认为是实现高安全性和高性价比锂金属电池的最有希望的解决方案。然而，由于不可逆的电解质消耗导致的局部电流集中而使阳极中死锂积累，活性锂储备不足以及固体电解质界面（SEI）处的 Li 转移缓慢，常规的 AFLMB 存在循环寿命短的问题。在此，将 SrI 引入到碳纸（CP）集流器中，通过包括可逆的 I/I 氧化还原反应在内的协同机制来有效抑制死锂，重新激活死锂，通过 SrF 和 LiF 形成具有介电性质的 SEI 表面，防止电解质分解，并在 SEI 内部形成具有丰富 LiI 的高离子传导性（3.488 mS cm）内层，从而实现 Li 的高效传输。采用 SrI 修饰的集流器，NCM532/CP 电池在 200 次循环后具有 129.2 mAh g 的容量，表现出前所未有的循环性能。
