Hu Ding, Zhu Guo-Rui, Zhang Ying-Ying, Yu Jia-Ling, Chen Si-Chong, Wu Gang, Wang Yu-Zhong
Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Advanced Polymeric Materials, College of Chemistry, Sichuan University, Chengdu, 610064, China.
Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Materials Science and Engineering, Sichuan University, Chengdu, 610064, China.
Small. 2025 Sep 5:e06784. doi: 10.1002/smll.202506784.
The LiAlTi(PO) (LATP)-polymer composite solid electrolyte offers environmental stability and safety for high-energy lithium metal batteries (LMBs), yet suffers from interfacial instability and high interfacial resistance. Herein, a Janus self-supporting skeleton (J-SSK) is engineered via multi-scale coupling of poly(vinylidene fluoride-trifluorethylene) (PVDF-TrFE), LATP, 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl) ureido) ethyl methacrylate (UPyMA) monomer, where intermolecular multiple hydrogen bonds reinforce mechanical robustness while the Janus structure isolates LATP from direct Li contact. In situ copolymerizing vinylene carbonate (VC) and UPyMA monomer in J-SSK to construct Janus composite quasi-solid electrolyte (J-CQSE) achieves seamless integration of electrode/electrolyte interfaces and establishes hierarchical coupling across J-SSK, polymer matrix, and lithium salts. The resultant J-CQSE demonstrates exceptional flame retardancy, high room-temperature ionic conductivity (1.2 mS cm), and superior Li transference number (0.75). The trade-off of its multi-scale coupling and competitive hydrogen bonding is realized, contributing to stable LiF/LiN-rich solid electrolyte interphase (SEI) and Li plating/stripping with persistent dendrite suppression. After 1000 cycles at room temperature, the LiFePO/Li full cell delivers capacity retentions of 89.5% at 1C, 98.9% at 4C, and 75.2% at 10C, respectively. The LiNiCoMnO/Li cell retains 72.9% capacity over 100 cycles at 0.2C. Importantly, the LFP/J-CQSE/Li pouch cell passes rigorous mechanical/thermal abuse and combustion tests, validating its practical viability for advanced safe LMBs.
锂铝钛（磷酸）（LATP）-聚合物复合固体电解质为高能锂金属电池（LMBs）提供了环境稳定性和安全性，但存在界面不稳定性和高界面电阻问题。在此，通过聚（偏二氟乙烯-三氟乙烯）（PVDF-TrFE）、LATP、2-（3-（6-甲基-4-氧代-1,4-二氢嘧啶-2-基）脲基）甲基丙烯酸乙酯（UPyMA）单体的多尺度耦合设计了一种Janus自支撑骨架（J-SSK），其中分子间多个氢键增强了机械强度，而Janus结构使LATP与锂直接接触隔离开来。在J-SSK中原位共聚碳酸亚乙烯酯（VC）和UPyMA单体以构建Janus复合准固体电解质（J-CQSE），实现了电极/电解质界面的无缝集成，并在J-SSK、聚合物基体和锂盐之间建立了分级耦合。所得的J-CQSE表现出优异的阻燃性、高室温离子电导率（1.2 mS cm）和优异的锂迁移数（0.75）。实现了其多尺度耦合和竞争性氢键的权衡，有助于形成稳定的富含LiF/LiN的固体电解质界面（SEI）以及抑制枝晶生长的锂电镀/剥离。在室温下进行1000次循环后，LiFePO/Li全电池在1C、4C和10C下的容量保持率分别为89.5%、98.9%和75.2%。LiNiCoMnO/Li电池在0.2C下经过100次循环后保持72.9%的容量。重要的是，LFP/J-CQSE/Li软包电池通过了严格的机械/热滥用和燃烧测试，验证了其在先进安全LMBs中的实际可行性。
