Aging Mechanisms of Lithium-ion Batteries

Modern society is making numerous efforts to reduce reliance on carbon-based energy systems. A notable solution in this transition is the adoption of lithium-ion batteries (LIBs) as potent energy sources, owing to their high energy and power densities. Driven by growing environmental challenges, the application scope of LIBs has expanded from their initial prevalence in portable electronic devices to include electric vehicles (EVs) and energy storage systems (ESSs). Accordingly, LIBs must exhibit long-lasting cyclability and high energy storage capacities to facilitate prolonged device usage, thereby offering a potential alternative to conventional sources like fossil fuels. Enhancing the durability of LIBs hinges on a comprehensive understanding of the reasons behind their performance decline. Therefore, comprehending the degradation mechanism, which includes detrimental chemical and mechanical phenomena in the components of LIBs, is an essential step in resolving cycle life issues. The LIB systems presently being commercialized and developed predominantly employ graphite anode and layered oxide cathode materials. A significant portion of the degradation process in LIB systems takes place during the electrochemical reactions involving these electrodes. In this review, we explore and organize the aging mechanisms of LIBs, especially those with graphite anodes and layered oxide cathodes.