Li3PO4‐Enriched SEI on Graphite Anode Boosts Li+ De‐Solvation Enabling Fast‐Charging and Low‐Temperature Lithium‐Ion Batteries

Abstract

AbstractLi+ de‐solvation at solid‐electrolyte interphase (SEI)‐electrolyte interface stands as a pivotal step that imposes limitations on the fast‐charging capability and low‐temperature performance of lithium‐ion batteries (LIBs). Unraveling the contributions of key constituents in the SEI that facilitate Li+ de‐solvation and deciphering their mechanisms, as a design principle for the interfacial structure of anode materials, is still a challenge. Herein, we conducted a systematic exploration of the influence exerted by various inorganic components (Li2CO3, LiF, Li3PO4) found in the SEI on their role in promoting the Li+ de‐solvation. The findings highlight that Li3PO4‐enriched SEI effectively reduces the de‐solvation energy due to its ability to attenuate the Li+‐solvent interaction, thereby expediting the de‐solvation process. Building on this, we engineer Li3PO4 interphase on graphite (LPO−Gr) anode via a simple solid‐phase coating, facilitating the Li+ de‐solvation and building an inorganic‐rich SEI, resulting in accelerated Li+ transport crossing the electrode interfaces and interphases. Full cells using the LPO−Gr anode can replenish its 80 % capacity in 6.5 minutes, while still retaining 70 % of the room temperature capacity even at −20 °C. Our strategy establishes connection between the de‐solvation characteristics of the SEI components and the interfacial structure design of anode materials for high performance LIBs.