Modulating NCM622 electrode to efficiently boost the lithium storage and thermal safety of its full batteries

High-energy-density lithium-ion batteries (LIBs) based on LiNixCoyMn1-x-yO2 cathodes necessitate a cost-effective and straightforward electrode modification technique to enhance both lithium storage capacity and thermal safety performance in industrial settings. This paper introduces an economically viable, convenient, and industrially feasible approach: the integration of minute quantities of TiO2 and TiN additives into the LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode, aimed at enhancing the performance of NCM622-TT||Graphite pouch full batteries, particularly in terms of lithium storage and thermal safety. Remarkably, under testing conditions of 45 °C and 1C rate, the TiO2&TiN-modified pouch full battery demonstrated a capacity retention rate of 82.6 % after 1000 cycles, representing a substantial improvement of over 53 % compared to the pure NCM622|| graphite pouch full battery. Furthermore, needling tests revealed a notable reduction of 12.4 °C in the average temperature increase during thermal runaway in the modified LIB, indicating a significant enhancement in safety. Comprehensive characterization and mechanistic analysis suggest that the incorporation of TiO2 and TiN enhances interfacial compatibility and stability, mitigates side reactions during cycling, and indirectly improves ion transport kinetics. Unlike traditional approaches involving electrode material modifications and battery structural design, modulating the NCM electrode offers a promising avenue for advancing the research and development of nickel-rich NCM LIBs, with considerable practical implications for industrial applications.