Constructing a multi-functional polymer network for ultra-stable and safe Li-metal batteries

Gao, Shilun; Li, Zhenxi; Zhang, Zhen; Li, Bingrui; Chen, Xi Chelsea; Yang, Guang; Saito, Tomonori; Tian, Ming; Yang, Huabin; Cao, Peng-Fei

doi:10.1016/j.ensm.2022.11.049

DOE OSTI · 1907219

Constructing a multi-functional polymer network for ultra-stable and safe Li-metal batteries

Gao, Shilun·Li, Zhenxi·Zhang, Zhen·Li, Bingrui·Chen, Xi Chelsea·Yang, Guang·Saito, Tomonori·Tian, Ming·Yang, Huabin·Cao, Peng-Fei

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Abstract

We report the practical application of lithium (Li) metal electrodes is impeded by Li dendrite growth and unstable solid electrolyte interphase (SEI). Herein, a multi-grafting polymer network, poly(dimethyl siloxane)-g-[poly(poly(ethylene glycol) methyl ether methacrylate)-r-sodium poly(p-styrene sulfonate)] (PPS), is chemically synthesized from reversible addition-fragmentation chain transfer (RAFT) polymerization. With integrated stretchability, ionic conductivity, and mechanical robustness, it serves a dual role to stabilize the Li electrode. As artificial SEI layer, the PPS enables superior electrochemical performance in half cells, symmetric cells, and full cells (PPS@Li/LiFePO 4 , capacity retention of >70% after 600 cycles). Utilized as solid polymer electrolyte (SPE), the all-solid-state Li/SPE/LiFePO 4 full cell delivers excellent cycling performance with an unprecedented capacity retention of 90% over 1,700 cycles at 0.5 C and 81% over 1,000 cycles at 1.0 C. With high-voltage LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) as cathode, the Li/SPE/NMC811 cell exhibits an initial discharge capacity of 162.2 mAh g -1 with a capacity retention of 72% after 200 cycles. The assembled solid-state Li/SPE/LiFePO4 pouch cell with SPE exhibits stable cycling performance over 200 cycles with a capacity retention of 75% and still operates well even after curling, folding, and cutting, demonstrating great potential for achieving ultra-safe and high energy density batteries.

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25 ENERGY STORAGE artificial solid electrolyte interphase elastic polymer network lithium-metal batteries solid polymer electrolyte

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Gao, Shilun, Li, Zhenxi, Zhang, Zhen, Li, Bingrui, Chen, Xi Chelsea, Yang, Guang, Saito, Tomonori, Tian, Ming, Yang, Huabin, Cao, Peng-Fei. 2022-11-28. Constructing a multi-functional polymer network for ultra-stable and safe Li-metal batteries. https://doi.org/10.1016/j.ensm.2022.11.049

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