A Novel Solid State Polymer Electrolyte for All Solid State Lithium Batteries

Abstract

All-solid-state lithium batteries (ASSLBs) have gained enormous interest due to their potential high energy density, high performance, and inherent safety characteristics for advanced energy storage systems. 1 Currently, solid-state ceramic (inorganic) electrolytes (SSCEs), solid-state polymer electrolytes (SSPEs), and a combination of the two (e.g., SSCE fillers in SSPEs) are being developed for ASSLBs. 2 Although SSCEs have high ionic conductivity and high electrochemical stability, 3 they experience some significant drawbacks, such as poor electrolyte/electrode interfacial properties and poor mechanical characteristics (brittle, fragile), 4 which can hinder their adoption to commercialization. Typically, SSCE-based ASSLBs require high cell stack pressures exerted by heavy fixtures for regular operations, which can reduce the energy density of the overall battery packages. 5 One promising solution to circumvent the aforementioned issues of SSCE-based ASSLBs is to develop SSPE-based AASLBs, since SSPEs can provide inherently good interfacial contacts with the electrodes that do not require high cell stack pressures. In addition, SSPEs are advantageous in making flexible batteries due to their elastic nature. 6 In this study, a novel method was developed to prepare a high-performance SSPE-based ASSLB, where a π-conjugated polymer was incorporated into a baseline polymer backbone, resulting in an improvement in ionic conductivity, thermal stability, and electrochemical stability. The novel SSPE demonstrated a superior electrochemical performance than the baseline when used in ASSLBs. The strategy developed in this study may lead to a new direction for the research and development of next-generation SSPE-based ASSLBs. References: (1) Chiu, K.-C.; Chang, J.-K.; Su, Y.-S. Recent Configurational Advances for Solid-State Lithium Batteries Featuring Conversion-Type Cathodes. Molecules 2023 , 28 (12), 4579. (2) Chen, A.; Qu, C.; Shi, Y.; Shi, F. Manufacturing strategies for solid electrolyte in batteries. Frontiers in Energy Research 2020 , 8 , 571440. (3) Li, S.; Zhang, S. Q.; Shen, L.; Liu, Q.; Ma, J. B.; Lv, W.; He, Y. B.; Yang, Q. H. Progress and perspective of ceramic/polymer composite solid electrolytes for lithium batteries. Advanced Science 2020 , 7 (5), 1903088. (4) Yu, X.; Manthiram, A. A review of composite polymer-ceramic electrolytes for lithium batteries. Energy Storage Materials 2021 , 34 , 282-300. (5) Hayashi, A.; Sakuda, A.; Tatsumisago, M. Development of sulfide solid electrolytes and interface formation processes for bulk-type all-solid-state Li and Na batteries. Frontiers in Energy Research 2016 , 4 , 25. (6) Jiang, Y.; Yan, X.; Ma, Z.; Mei, P.; Xiao, W.; You, Q.; Zhang, Y. Development of the PEO based solid polymer electrolytes for all-solid state lithium ion batteries. Polymers 2018 , 10 (11), 1237. Acknowledgment This work was supported by the Larry and Linda Pearson Endowed Chair at the Department of Mechanical Engineering, South Dakoda School of Mines and Technology and by the South Dakota Governor’s Research Center for Electrochemical Energy Storage.