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[Display omitted] Polyvinylidene difluoride (PVDF) is one of the most attractive electrolyte materials for solid-state batteries due to its high ionic conductivity, however, the battery performance is limited by the high electrolyte–electrode interfacial resistance. Herein, PVDF polymer mixed with ceramic Li 7 La 3 Zr 2 O 12 is coated on cellulose support membrane (PLCSM) through a simple slurry-casting method. The ionic transport of PLCSM is originated from dimethyl formamide (DMF)-Li+ solvation structure, which plays a critical role in conducting lithium ions. β-PVDF after dehydrofluorination offers a high dielectric constant and enhances the dissociation of lithium salt. As a result, PLCSM with a total thickness of 85 µm presents an oxidation voltage of 4.9 V. Li-Li symmetric cells by employing PLCSM reveal that the critical current density (CCD) is increased to 1 mA cm−2. A full cell of LiFePO 4 |PLCSM |Li with high mass loading (1.2 mA h cm−2) shows a first-cycle discharge capacity of 160 mA h g−1. With LiNi 0.6 Mn 0.2 Co 0.2 O 2 as the cathode, the initial discharge capacity is 153 mA h g−1, and the capacity retention after 80 cycles is 80 %. The sandwiched PLCSM provides an effective strategy to achieve high-performance dendrite-free Li metal batteries. [ABSTRACT FROM AUTHOR]

The low coulombic efficiency and poor cycle performance deriving from uncontrolled growth of dendrites have caused a serious obstacle to the practical application of lithium metal. Herein we propose a bifunctional regular-random dual cross-linking network solid polymer electrolyte (RRa-SPE) for dendrite-free all-solid-state lithium metal batteries. Under the synergistic effect of regular polymerization skeleton and random cross-linking network, the RRa-SPE effectively regulates the lithium deposition and facilitates the generation of a highly homogeneous and robust solid-electrolyte interphase (SEI) layer on lithium metal. Besides, this RRa-SPE shows benign ionic conductivity of 4.36 × 10−4 S cm−1 (at 30 °C), high lithium ion transference number of 0.76 and enhanced mechanical strength. The Li/RRa-SPE/Li symmetric cell maintains low and stable voltage polarization (0.15 V) after circulating for 1200 h at 0.5 mA cm−2. Improved LiFePO 4 /RRa-SPE/Li cell exhibits excellent rate capability and prominent cycle performance with a capacity retention of 99.6% after 240 cycles at 0.5 C at 30 °C. Image 1 The SPE is prepared via a facile UV-derived dual-reaction. With bifunctional network, the SPE effectively regulates the lithium deposition. The SPE shows enhanced ionic conductivity of 4.36 × 10−4 S cm−1 at 30 °C. The SPE exhibits high lithium ion transference number of 0.76. [ABSTRACT FROM AUTHOR]