锂离子电池正极补锂技术研究进展

The formation of a solid electrolyte interface (SEI) on the surface of anodes leads to the irreversible consumption of the active lithium in lithium-ion battery systems during the first charge. This results in capacity fading and cycle life decay, particularly in the case of high-energy-density battery designs. Compensation of active lithium can be an effective way to solve such problems. The recent prelithiation strategies can be mainly divided into cathode and anode prelithiation based on the process method. Notably, cathode prelithiation technology has attracted wide attention because of its safety and high compatibility with battery-manufacturing processes. Cathode prelithiation technology mainly refers to adding lithium-containing compounds with high irreversible capacity into cathodes; in other words, cathode lithium additives are used. The main cathode lithium supplement additives are binary lithium-containing compounds, ternary lithium-containing compounds, and organic lithium-containing compounds. In addition, the active lithium replenishment of cathodes can be achieved by designing over-lithiated cathode materials. This study summarizes the research progress of cathode prelithiation strategies for improving the initial efficiency, energy density, and cycle life of lithium ion batteries. Different strategies are compared. The prospect for further commercialization of cathode prelithiation strategies is also predicted.