An Hanwen, Li Menglu, Liu Qingsong, Song Yajie, Liu Jiaxuan, Yu Zhihang, Liu Xingjiang, Deng Biao, Wang Jiajun
MOE Engineering Research Center for Electrochemical Energy Storage and Carbon Neutrality in Cold Regions, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, PR China.
National Key Laboratory of Chemical and Physical Power Sources, Tianjin Institute of Power Sources, Tianjin, PR China.
Nat Commun. 2024 Oct 23;15(1):9150. doi: 10.1038/s41467-024-53094-8.
Polyethylene oxide (PEO) based electrolytes critically govern the security and energy density of solid-state batteries, but typically suffer from poor oxidation resistance at high voltages, which limits the energy density of batteries. Here, we report a Lewis-acid coordinated strategy to significantly improve the cyclic stability of 4.8 V-class PEO-based battery. The introduced Mg and Al with strong electron-withdrawing capability weaken the electron density of ether oxygen (EO) chains via chelation in the coordination structure, resulting in a locally limited interaction between the EO chains and the surface of cathodes at high state of charge. The batteries using Lewis-acid coordinated electrolytes and Ni-rich cathodes achieve high voltage stability of 4.8 V over 300 cycles. Further, the realization of industrial-scale electrolyte membranes, and Ah-level pouch cells over 586 Wh kg with good cyclic stability, suggests the potential of our strategy in practical applications of all-solid-state batteries.
基于聚环氧乙烷（PEO）的电解质对固态电池的安全性和能量密度起着关键作用，但通常在高电压下抗氧化性较差，这限制了电池的能量密度。在此，我们报道一种路易斯酸配位策略，可显著提高基于PEO的4.8V级电池的循环稳定性。引入的具有强吸电子能力的镁和铝通过配位结构中的螯合作用削弱了醚氧（EO）链的电子密度，导致在高充电状态下EO链与阴极表面之间的局部相互作用受限。使用路易斯酸配位电解质和富镍阴极的电池在300次循环中实现了4.8V的高电压稳定性。此外，工业规模电解质膜的实现以及超过586 Wh kg且具有良好循环稳定性的Ah级软包电池表明了我们的策略在全固态电池实际应用中的潜力。
