Modified anodes for lithium metal batteries

FERNANDO P. COMETTO; GUADALUPE PEÑARANDA; C. ANDREA CALDERÓN; M. VICTORIA BRACAMONTE

Buenos Aires

Simposio; VIII Symposium on Hydrogen, Fuel Cells and Advanced Batteries; 2022

Comision Nacional de Energía Atómica

Lithium metal anode represents the ?holy grail? of battery research since its high theoretical specific capacity (3860 mA h g−1) and lowest redox potential (−3.04 V vs. the standard hydrogen electrode). However, there are some problems due the huge reactivity of lithium that need to be addressed. It is known that, during cell assembling, when the electrolyte comes into contact with metallic lithium it decomposes forming a solid electrolyte interface (SEI) that is chemically stable and Li+ ions conductor. During successive lithium dissolution/deposition ions diffuse through the SEI, due to inhomogeneities on the surface cracks and holes are formed in the interface, favoring formation of high surface area lithium (HSAL) [1]. This causes continuous consumption of lithium and electrolyte, decrease in coulombic efficiency and safety problems due to internal short circuits. One strategy to solve this problem is the modification of the metal surface to improve the deposition and dissolution of lithium process [2,3]. In this work we use the two-dimensional hexagonal boron nitride (hBN) to modify the surface of lithium electrode and to improve cyclability of the cell.[1] Eastwood, D. S., Bayley, P.M., Chang, H.J.,  Taiwo, O., Vila-Comamala, J., Brett, D., Rau, C., Withers, P.J., Shearing, P.R., Grey, C.P.,  Lee, P.D. Three-dimensional characterization of electrodeposited lithium microstructures using synchrotron X-ray phase contrast imaging. Chem. Commun. 12, 161?175 (2018).[2] Placke, T., Kloepsch, R., Dühnen, S. & Winter, M. Advances in Interfaces between Li Metal Anode and Electrolyte. Adv. Mater. Interfaces. 5, 1701097?1701116 (2018).[3] Calderón, C.A., Vizintin, A., Bobnar, J., Barraco, D.E., Leiva, E., Visintin, A., Fantini, S., Fischer, F., Dominko, R. Lithium Metal Protection by a Cross-Linked Polymer Ionic Liquid and Its Application in Lithium Battery. ACS Appl. Energy Mater. 3, 2020?2027 (2020).