Co-free gradient lithium-rich cathode for high-energy batteries with optimized cyclability

Yang, Haotian [Beijing University of Technology (China)]; Wang, Lihang [Beijing University of Technology (China)]; Li, Yuqiang [Beijing University of Technology (China)]; Zhuo, Zengqing [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)]; Wu, Tianhao [Beijing University of Technology (China)]; Liu, Jie [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)]; Xu, Ligang [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)]; Du, Haozhe [Beijing University of Technology (China)]; Liu, Shiqi [Beijing University of Technology (China)]; Wu, Lingqiao [Beijing University of Technology (China)]; Zhao, Shu [Beijing University of Technology (China)]; Tang, Mingxue [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)] (ORCID:0000000158195048); Yang, Wanli [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000306668063); Yu, Haijun [Beijing University of Technology (China)] (ORCID:0000000302049943)

doi:10.1073/pnas.2412460121

DOE OSTI · 2566386

Co-free gradient lithium-rich cathode for high-energy batteries with optimized cyclability

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Abstract

Lithium-rich layered oxides (LLOs) hold the promise for high-energy battery cathodes. However, its application has been hindered by voltage decay associated with irreversible reactions at high voltages despite decades of intensive efforts. Here, we first theoretically studied the molecular orbitals of Mn-based Li-rich configurations. We found that the π-bond ring formed within the LiMn 6 structure could participate in stable redox reactions as one unit, but Co could disrupt its symmetry. We thus designed and synthesized Co-free concentration-gradient LLOs (CF-CG-LLOs) materials. The combination of concentration gradient and Co removal leads to exceptional capacity retention without any fading over 100 cycles of the pouch cell. More importantly, it exhibits an extraordinarily low voltage decay of 0.15 mV/cycle, accompanied by a high Coulombic efficiency of 99.86%. This concept and demonstration of CF-CG-LLO cathodes reveal a viable avenue toward low-cost, high-energy-density battery cathodes.

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25 ENERGY STORAGE battery cathode concentration gradient lithium ion batteries lithium-rich layered oxides redox mechanism

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Yang, Haotian [Beijing University of Technology (China)], Wang, Lihang [Beijing University of Technology (China)], Li, Yuqiang [Beijing University of Technology (China)], Zhuo, Zengqing [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)], Wu, Tianhao [Beijing University of Technology (China)], Liu, Jie [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)], Xu, Ligang [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)], Du, Haozhe [Beijing University of Technology (China)], Liu, Shiqi [Beijing University of Technology (China)], Wu, Lingqiao [Beijing University of Technology (China)], Zhao, Shu [Beijing University of Technology (China)], Tang, Mingxue [Center for High Pressure Science and Technology Advanced Research (China); University of Science and Technology Beijing (China)] (ORCID:0000000158195048), Yang, Wanli [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000306668063), Yu, Haijun [Beijing University of Technology (China)] (ORCID:0000000302049943). 2024-12-04. Co-free gradient lithium-rich cathode for high-energy batteries with optimized cyclability. https://doi.org/10.1073/pnas.2412460121

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