EKC2023

Solid-State Polymer Electrolytes for Lithium-Metal Batteries

Aug 16, 2023, 2:10 PM

20m

Venus 1

Chemical Engineering and Material Science [CM1] Advancements in Battery Technology: From Materials to Applications

Speaker

Unho JUNG (Helmholtz Institute Ulm (Karlsruhe Institute of Technology))

Description

Lithium-metal batteries (LMBs) are among the most promising next-generation energy storage systems. In such systems, the anode is composed of lithium (Li) metal, ideally originating from the cathode active material in order to avoid the initial presence of metallic lithium when assembling the cells (also referred to as “zero excess” LMBs). Generally, Li metal offers a high theoretical capacity of 3860 mAhg-1 and a very low reduction potential of -3.040 V vs. the standard hydrogen electrode, rendering it an excellent anode material candidate for higher energy density batteries (i.e., > 500 Wh kg-1). Nonetheless, the continuous degradation of commonly used liquid electrolytes at the interface with Li metal leads to a severe decrease in Coulombic Efficiency, especially in absence of an initial lithium reservoir, and dendritic Li deposition, which can potentially cause cell failure and accidental short-circuiting.1,2,3
Several strategies to improve the stability of the initially formed interphase have been proposed, including tailored electrolyte compositions, the application of artificial interphases, the use of 3D host matrices for the lithium deposition, and the replacement of conventional liquid electrolytes by solid-state electrolytes.4,5,6,7 Concerning the latter, polymer electrolytes (PEs), especially poly(ethylene oxide) (PEO) based ones, are characterized by several attractive properties, e.g., high flexibility, low cost, adhesive interfacial contact to the electrodes, light weight, and reasonable ionic conductivity at slightly elevated temperatures.8,9 However, the interfacial contact in “zero-excess” cell configurations remains a great challenge.
Herein, we report on our progress regarding the development of advanced current collectors with modified surfaces to achieve enhanced lithium deposition kinetics, greater reversibility, and improved Coulombic efficiency for “zero-excess” LMBs.

References

1. Horstmann, B. et al. Strategies towards enabling lithium metal in batteries: Interphases and electrodes. Energy and Environmental Science 14 5289–5314 Preprint at https://doi.org/10.1039/d1ee00767j (2021).
2. Adenusi, H., Chass, G. A., Passerini, S., Tian, K. v. & Chen, G. Lithium Batteries and the Solid Electrolyte Interphase (SEI)—Progress and Outlook. Advanced Energy Materials Preprint at https://doi.org/10.1002/aenm.202203307 (2023).
3. He, X., Bresser, D., Passerini, S. et al. The passivity of lithium electrodes in liquid electrolytes for secondary batteries. Nat Rev Mater 6, 1036–1052 (2021).
4. Tong, Z., Bazri, B., Hu, S. F. & Liu, R. S. Interfacial chemistry in anode-free batteries: challenges and strategies. Journal of Materials Chemistry A vol. 9 7396–7406 Preprint at https://doi.org/10.1039/d1ta00419k (2021).
5. Kim, S. et al. Lithium Metal Batteries: From Fundamental Research to Industrialization. Advanced Materials Preprint at https://doi.org/10.1002/adma.202206625 (2023).
6. Mayer, A. et al. Influence of Polymer Backbone Fluorination on the Electrochemical Behavior of Single-Ion Conducting Multiblock Copolymer Electrolytes. ACS Macro Lett 11, 982–990 (2022).
7. Liang, H-P. et al. Polysiloxane-Based Single-Ion Conducting Polymer Blend Electrolyte Comprising Small-Molecule Organic Carbonates for High-Energy and High-Power Lithium-Metal Batteries. Adv. Energy Mater. 12, 16 (2022)
8. Yusim, Y. et al. Evaluation and Improvement of the Stability of Poly(ethylene oxide)-based Solid-state Batteries with High-Voltage Cathodes. Angew. Chem. Int. Ed. 62, 12 (2023)
9. Chen, Y-H. et al. Towards All-Solid-State Polymer Batteries: Going Beyond PEO with Hybrid Concepts. Adv. Funct. Mater. 2300501 (2023)