Review on modification strategy of layered transition metal oxide for sodium ion battery cathode material

Sodium-ion batteries (SIBs) are undergoing a significant resurgence to either complement or substitute the costly lithium-ion batteries (LIBs) in electrical energy storage systems and other applications. However, the development of SIBs is hindered by issues such as low energy density, short cycle life, and the large ionic radius of sodium. Therefore, developing high performance cathode materials is crucial for enhancing the overall performance of SIBs. Among various cathode materials, layered transition metal oxides (LTMO) have attracted significant attention due to their advantages, including low cost, simple preparation process, and dense structure. Nevertheless, LTMO materials face challenges such as complex phase transitions, sluggish ion transport kinetics, and interface issues between the electrode and electrolyte during charge and discharge process, making their modification necessary. This paper reviews recent advances in the modification strategies of LTMO materials such as doping, morphology control, and surface coating. It also discusses future development directions, aiming to accelerate the application of LTMO in SIBs and promote their early commercialization.