High-Performance Cobalt-Free Nickel-Rich Layered Li[Ni_0.9Mn_0.1]O₂ Cathode Materials

Abstract

With growing demands for low-cost, large-format lithium-ion batteries mainly for electric vehicles (EVs) and energy storage system (ESS), escalating price and unsustainable supply of cobalt have become increasingly acute.1 Moreover, owing to the toxic nature and an increasing concern for child labor used in ore mining, significant research is being devoted to decrease the share or completely removing cobalt from the current cathode families, particularly in high-capacity Ni-rich layered cathodes which have sufficiently high potential for commercialization.2-5 This study involves a systematic investigation on the Ni-rich Li[Ni0.9Co0.1-xMnx]O2 (x = 0, 0.05, and 0.1) layered cathodes by variation of the Mn to Co content. Remarkably, Co-free Li[Ni0.9Mn0.1]O2 (NM90) exhibits outstanding mechanical and microstructural stability resulted in excellent cycling performance, which outperformed its Co-containing Li[Ni0.9Co0.1]O2 and Li[Ni0.9Co0.05Mn0.05]O2 counterparts. Alongside observations of high voltage and high-temperature stability, Co-free NM90 demonstrate substantially higher capacity retention, increasing the attractiveness of this material for practical application. To elucidate the impact of the Mn content in Ni-rich cathodes, the characterization techniques such as in-situ XRD, TEM and micro-compression analysis as well as electrochemical measurements have conducted and provided valuable information regarding the intrinsic properties of individual cathode components and their effects on electrochemical performance of the cathode materials. References Y.-K. Sun, D. J. Lee, Y. J. Lee, Z. Chen and S.-T. Myung, ACS Appl. Mater. Interfaces 2013, 5, 11434. U.‐H. Kim, D.‐W. Jun, K.‐J. Park, Q. Zhang, P. Kaghazchi, D. Aurbach, D. T. Major, G. Goobes, M. Dixit, N. Leifer, C. M. Wang, P. Yan, D. Ahn, K.‐H. Kim, C. S. Yoon and Y.‐K. Sun, Energy Environ. Sci. 2018, 11, 1271. K.-J. Park, M.-J. Choi, F. Maglia, S.-J. Kim, K.-H. Kim, C. S. Yoon and Y.-K. Sun, Adv. Energy Mater. 2018, 8, 1703612. U.‐H. Kim, H.‐H. Ryu, J.‐H. Kim, R. Mücke, P. Kaghazchi, C. S. Yoon and Y.‐K. Sun, Adv. Energy Mater. 2019, 9, 1803902. U.‐H. Kim, L.-Y. Kuo, P. Kaghazchi, C.S. Yoon and Y.-K. Sun, ACS Energy Lett. 2019, 4, 576.