High-Energy-Density, Long-Life Li-Metal Batteries via Application of External Pressure

Abstract

Theapplication of commercially available carbonate-basedelectrolytesto Li-metal batteries (LMBs) is challenging because of the uncontrollableside reactions of the electrolytes with Li anodes. Herein, a practicalcarbonate-electrolyte-based LMB with a high areal capacity and longcycle life is proposed. The cycling stability of the proposed LMBis established by applying an external compressive pressure (1200kPa) and a boehmite-coated separator to prevent the short circuitof the electrodes. The external pressure drives the growth of theLi metal as a dense uniform layer instead of dendrites and mitigatesthe formation of microcracks in the charged Ni-rich layered cathode.The unprecedented cycling stability of the stacked LMB with a Ni-richlayered cathode, retaining 82.0% of its initial capacity after 500cycles, can prove instrumental in realizing practical high-energy-densityLMBs, thus demonstrating the possibility of employing cell compressionto increase the life and energy density of LMBs.