Strategies for improving electrochemical reaction kinetics of cathode materials for subzero-temperature Li-ion batteries: A review

Lithium-ion batteries (LIBs) have been widely used as the main power sources for consumer electronics and electric vehicles. However, LIBs are usually suffered from serious reduction in energy and cruising ability when operated below 0 °C, owing to the sluggish Li+ion transport kinetics in the bulk electrodes, electrolyte, and their interfaces. In this review, the recent important advances in improving the electrochemical reaction kinetics for the subzero operations of LIBs based on the cathode perspective are summarized. Firstly, we mainly discussed the influences of subzero temperatures on the electrochemical reaction kinetics for several typical cathode materials, including olivine LiFePO4 (LFP) and Li3V2(PO4)3 (LVP) phosphates, layered LiCoO2 (LCO), Ni-rich LiNi1-x-yCoxMnyO2 (NCM) and LiNi1-x-yCoxAlyO2 (NCA) oxides, as well as Li- and Mn-rich Li1-xNi1-x-y-zCoyMnzO2 (LMR) oxides. Then, various strategies developed for enhancing the interfacial and internal electrochemical reaction kinetics for these typical cathode materials under subzero temperatures are detailly discussed in detail. Subsequently, a short comparison and overview of studies and related properties of the LFP, LVP, NCM and LMR cathode materials are provided. Finally, the specific suggestions and ideas for dealing with the challenges of the slow kinetics for cathode materials under subzero temperatures are put forward, inspiring the further developments of LIBs and other devices for subzero-temperature applications.