华中科技大学谢佳团队近日实现了植酸钠稳定高镍氧化物阴极中的晶格氧，用于热失控抑制和高压操作。相关论文于2025年5月29日发表在《科学通报》杂志上。

富镍层状氧化物阴极（LiNi_xCo_yMn_1-x-yO₂，NCM）释放的活性氧（O*）是引发锂离子电池（LIB）热失控（TR）的原因。具体而言，NCM中从过渡金属（TM）3d到氧（O）2p的电荷补偿在O*释放中起着关键作用。 

受植酸钠（PN）对TM的强螯合作用的启发，研究组采用PN作为阴极添加剂与镍配位，从而削弱了LiNi_0.8Co_0.1Mn_0.1O₂（NCM811）表面TM 3d对O 2p的电荷补偿，最终提高了电池的安全性。结果表明，螯合成功地稳定了晶格氧并抑制了O*的释放，防止了NCM811中的有害相变，并减少了O*相关串扰反应的热量产生。

因此，带有PN的NCM811袋式电池的TR触发温度（T_tr）从125.9°C升高到184.8°C，而最高温度（T_max）从543.7°C降低到319.7°C。此外，PN衍生的改性层允许NCM811在4.6 V下保持超过700次循环的卓越循环稳定性。该策略为稳定NCM中的晶格氧、抑制O*触发的TR和提高高压性能提供了一种简便的方法。

附：英文原文

Title: Sodium phytate stabilizing lattice oxygen in high-nickel oxide cathodes for thermal runaway inhibition and high voltage operation

Author: Ziqi Zeng a, Jia Xie a

Issue&Volume: 2025/05/29

Abstract: The reactive oxygen species (O*) released from the nickel-rich layered oxide cathodes (LiNixCoyMn1xyO2, NCM) are responsible for triggering thermal runaway (TR) in lithium-ion batteries (LIBs). Specifically, the charge compensation from transition metal (TM) 3d to oxygen (O) 2p in NCM plays a pivotal role in O* release. Here, inspired by the strong chelating effect of sodium phytate (PN) on TM, we employ PN as a cathode additive to coordinate with nickel, thereby weakening the charge compensation of TM 3d to O 2p on the surface of LiNi0.8Co0.1Mn0.1O2 (NCM811) and ultimately enhancing battery safety. It is shown that the chelation successfully stabilizes lattice oxygen and suppresses the release of O*, preventing detrimental phase transitions in NCM811 and reducing heat generation from O* related crosstalk reactions. Consequently, the TR trigger temperature (Ttr) of NCM811 pouch cell with PN elevates from 125.9 to 184.8 °C, while the maximum temperature (Tmax) decreases from 543.7 to 319.7 °C. Moreover, the PN-derived modification layer allows NCM811 to maintain exceptional cycling stability for over 700 cycles at 4.6 V. This strategy provides a facile method for stabilizing lattice oxygen in NCM, inhibiting O*-triggered TR, and enhancing high-voltage performance.

DOI: 10.1016/j.scib.2025.05.035

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927325005754