Ahn Heeju, Park Yeonju, Nam Kwan Woo
Department of Chemical Engineering and Materials Science, and Graduate Program in System Health and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea.
ChemSusChem. 2025 Jan 14;18(2):e202400823. doi: 10.1002/cssc.202400823. Epub 2024 Oct 23.
Lithium-ion batteries have gained widespread use in various applications, including portable devices, electric vehicles, and energy storage systems. High Ni cathode, LiNiCoMnO (NCM, x≥0.8, x+y+z=1), have garnered significant attention owing to their high energy density. However, the limited Li-ion transfer rate and transition metal cross-talk to anode pose obstacles to further improvement of electrochemical performance. To tackle these challenges, metal-organic frameworks (MOFs) with chelating agents are employed as additive materials for electrode. MOFs with chelating agents offer three key attributes: (1) Effective mitigation of transition metal cross-talk to the anode, (2) Partial desolvation of Li ions through MOF pores, and (3) Immobilization of anions via metal sites in the MOF. Leveraging these advantages, the chelating MOF-modified NCM cathode demonstrates reduced charge transfer resistance, both in their pristine and cycled states. In addition, they exhibit significantly improved the Li-ion diffusion coefficients after 100 cycles. These findings underscore the potential of MOFs with chelating agents as promising additive materials for enhancing the performance of LIBs.
锂离子电池已在包括便携式设备、电动汽车和储能系统在内的各种应用中得到广泛使用。高镍阴极LiNiCoMnO（NCM，x≥0.8，x+y+z=1）因其高能量密度而备受关注。然而，锂离子传输速率有限以及过渡金属与阳极之间的串扰给电化学性能的进一步提升带来了障碍。为应对这些挑战，带有螯合剂的金属有机框架（MOF）被用作电极的添加剂材料。带有螯合剂的MOF具有三个关键特性：（1）有效减轻过渡金属与阳极之间的串扰；（2）通过MOF孔隙使锂离子部分去溶剂化；（3）通过MOF中的金属位点固定阴离子。利用这些优势，螯合MOF修饰的NCM阴极在其原始状态和循环状态下均显示出降低的电荷转移电阻。此外，它们在100次循环后锂离子扩散系数显著提高。这些发现突出了带有螯合剂的MOF作为有望提高锂离子电池性能的添加剂材料的潜力。
