近日，中山大学王成新团队通过聚合物辅助形成独特的界面，促进锂离子的均匀传输，实现稳定的4.7 V锂金属电池。该项研究成果发表在2025年5月10日出版的《国家科学评论》上。

由于界面不稳定和锂离子传输不均匀，导致枝晶形成和阴极退化，实现锂金属电池（LMB）在高压下的稳定循环是一个重大挑战。构建促进快速均匀离子传输的固体电解质界面（SEI）对于提高电极结构的稳定性至关重要。然而，目前的研究主要集中在界面不稳定性上，而忽视了更为关键的不均匀离子输运。

研究组通过将乙醇铝（Al（EtO）₃）、氟代碳酸乙烯酯（FEC）和五氟环三磷腈（PFPN）掺入碳酸盐基电解质中，开发了一种新型电解质体系（PAFE）。 Al（EtO）₃作为交联剂，有助于形成三维聚合物网络，促进无机成分如LiF、Li₃N、Li₃P和Al₂O₃在SEI和阴极电解质界面（CEI）内的均匀沉积。这些均匀的界面降低了锂离子传输的活化能，从而确保了一致的离子流动并降低了电极内的内应力。因此，具有PAFE的LiNi_0.8Co_0.1Mn_0.1O₂（NCM811）电池表现出卓越的循环稳定性，在4.7的高截止电压下，在140次循环中保持了80%的容量?V.此外，1?Ah袋式电池表现出优异的循环性能，突显了这种电解质系统在实际高能量密度LMB应用中的潜力。

附：英文原文

Title: Facilitating uniform lithium-ion transport via polymer-assisted formation of unique interfaces to achieve stable 4.7 V Li metal battery

Author: Li, Xinqi, Li, Zhaojie, Li, Chuang, Tian, Fei, Qiao, Zhengping, Lei, Danni, Wang, Chengxin

Issue&Volume: 2025-05-10

Abstract: Achieving stable cycling of lithium metal batteries (LMBs) at high voltages presents a significant challenge due to interfacial instability and uneven lithium-ion transport, leading to dendrite formation and cathode degradation. Constructing a solid-electrolyte interphase (SEI) that facilitates fast and uniform ion transport is crucial for enhancing the stability of electrode structures. However, current research mainly focuses on interfacial instability while neglecting uneven ion transport, which is even more critical. In this study, we develop a novel electrolyte system (PAFE) by incorporating aluminum ethoxide (Al(EtO)3), fluoroethylene carbonate (FEC), and pentafluorocyclotriphosphazene (PFPN) into a carbonate-based electrolyte. Al(EtO)3 serves as a crosslinking agent, facilitating the formation of a three-dimensional polymer network that promotes the uniform deposition of inorganic components such as LiF, Li3N, Li3P and Al2O3 within the SEI and cathode-electrolyte interphase (CEI). These uniform interphases lower the activation energy for lithium-ion transport, thereby ensuring consistent ion flow and reducing internal stress within the electrodes. As a result, Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) cells with PAFE exhibit exceptional cycling stability, retaining 80% capacity over 140 cycles at a high cut-off voltage of 4.7V. Furthermore, 1Ah pouch cells demonstrate excellent cycling performance, highlighting the potential of this electrolyte system for practical high-energy-density LMBs applications.

DOI: 10.1093/nsr/nwaf182

Source: https://dx.doi.org/10.1093/nsr/nwaf182