EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Lithium-metal solid‐state batteries based on solid polymer electrolytes are at the forefront of the candidates to face energy density and safety issues encountered by conventional Li-ion batteries. Dry solid electrolytes have been developed for several decades [1] but still face several challenges to be compatible at high voltages [2] and versus Li metal [3] at the same time. The combination of different organic polymer layers within the same electrochemical device may bring remarkable benefits towards high-performance solid-state batteries. Ideally, the selection of the polymers must be done according to their compatibility with the negative electrode (Li0) and the positive active material. However, this approach is not straightforward, and requires a thorough understanding to attain performing devices. In this work, two common dry polymers have been combined within the same device to assemble Li-metal solid-state batteries. The success of such approach relies on the in-depth understanding on the thermodynamics of the polymer mixture. For this purpose, Nuclear Magnetic Resonance (NMR), Electrochemical Impedance Spectroscopy (EIS) and galvanostatic cycling have been applied as powerful techniques to provide insights on the kinetics, compatibility between materials, ion transport phenomena, interfacial kinetics and electrochemical performance. Following this approach, solid-state cells using LiFePO4 and NMC active materials were successfully studied. The present work will illustrate the importance on the choice of materials on the rational design and development of Li-metal solid-state batteries.

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2. López-Aranguren P, Judez X, Chakir M, Armand M, Buannic L. JournalofTheElectrochemical Society. 2020 Jan 31;167(2)
3. Golozar M, Paolella A, Demers H, Bessette S, Lagacé M, Bouchard P, et al. Communications Chemistry. 2019 Nov 15;2(1).