中国科学技术大学季恒星团队报道了石墨阳极上富集Li₃PO₄的SEI促进Li⁺脱溶剂，实现快速充电和低温锂离子电池。相关研究成果于2024年3月14日发表在《德国应用化学》。

固体电解质界面（SEI）-电解质界面的Li⁺去溶剂化，是限制锂离子电池（LIBs）快速充电能力和低温性能的关键步骤。作为阳极材料界面结构的设计原则，解开SEI中促进Li⁺去溶剂化的关键成分的贡献并破译其机制仍然是一个挑战。

该文中，研究人员对SEI中发现的各种无机成分（Li₂CO₃、LiF、Li₃PO₄）在促进Li⁺脱溶剂化中的作用进行了系统的探索。研究结果强调，富含Li₃PO₄的SEI由于其减弱Li⁺-溶剂相互作用的能力而有效地降低了脱溶剂化能量，从而加快了脱溶剂过程。

在此基础上，研究人员通过简单的固相涂层在石墨（LPO-Gr）阳极上设计了Li₃PO₄界面，促进了Li⁺的脱溶剂化，并构建了富含无机物的SEI，从而加速了Li⁺穿过电极界面和界面的传输。使用LPO-Gr阳极的全电池可以在6.5分钟内补充80%的容量，即使在-20°C的温度下仍能保持70%的室温容量。

该策略建立了SEI组分的去溶剂化特性与高性能LIBs阳极材料的界面设计之间的联系。

附：英文原文

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

Author: Chaonan Wang, Yuansen Xie, Yingshan Huang, Shaoyun Zhou, Huanyu Xie, Hongchang Jin, Hengxing Ji

Issue&Volume: 2024-03-14

Abstract: Li+ 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 interphasial structure of anode materials, is still a challenge. Herein, we embark on 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 interphasial design of anode materials for high performance LIBs.

DOI: 10.1002/anie.202402301

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202402301