Lithium-plating suppressed graphite enables fast and low-temperature charging capability for safe lithium-ion pouch cell
Graphite-based Li-ion batteries (LIBs) can pose safety risks under harsh conditions due to undesired Li plating, involving sluggish Li + desolvation and diffusion through SEI, which is strongly determined by interfacial solvation structure. Here, we develop a kilogram-level preparation of lithium-plating suppressed graphite (LPSG) by incorporating a defective N and Co-doped carbon layer, which can induce low-solvent coordination Li + solvation structure in the inner Helmholtz plane. The underlying nanoscale interfacial solvation structure and interface chemistry regulation mechanism is revealed. The Co and N in the coating layer can generate local electron deviation, thus preferentially absorbing anions and making more anions participate in the first solvation sheath. Combined with facilitating P-F bond breaking, an inorganic-rich SEI is prompted to form, which enhances ion transport and achieves lithium-plating suppressed. Notably, the 5 Ah LFP||LPSG pouch cell demonstrates an extremely fast-charging capability (10C-rate constant current charging for 90.4 % of the 1C-rate capacity in less than 6 min). When charging at −20℃ and 0.5 C, the capacity retention of the pouch cell with LPSG improves nearly 20 times more than pristine graphite. More impressively, the LPSG enables the cell to exhibit a significant increase in thermal runaway trigger temperature (195.3℃ vs. 152.3℃) after being charged fully at 10 C. This work provides a novel insight into regulating the interfacial solvation structure and interface chemistry based on the electrode surface structure for high-safety LIBs.
危险品化学品经营许可证（带存储）