Cyclability Investigation of Anode-Free Lithium-Metal Batteries

Abstract

Lithium (Li) is a sought-after element for thrift, and considerable effort is being invested in conserving, reusing, and optimizing its chemical capabilities as a key material for energy storage systems. Anode-free lithium-metal batteries (AFLMB) provide the ability to utilize the exact amount of Li in the battery, thereby increasing both the specific capacity and safety of the battery. AFLMBs are widely recognized and investigated due to their promised benefits but have not yet become commercial, primarily because they suffer from uneven Li deposition. This issue results in Li dendrite formation, electrolyte consumption due to poor solid electrolyte interphase properties, and, generally, safety concerns. Overcoming these challenges would bring humanity one step closer to a desirable zero-carbon emission future, as more energy could be stored in less volume and weight. In this study, we examined an AFLMB system and investigated different physical and electrochemical factors to understand their effects on the nature of Li deposition/dissolution processes and on the cyclability of the battery. The effects of electrode architecture, cycling temperature, current density in the first charge, and salt composition on the battery were investigated using electrochemical impedance spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy.