Liu Yu, Peng Hongling, Su Han, Zhong Yu, Wang Xiuli, Xia Xinhui, Gu Changdong, Tu Jiangping
State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
CCTEG Chongqing Research Institute, Chongqing, 400039, China.
Adv Mater. 2022 Jan;34(3):e2107346. doi: 10.1002/adma.202107346. Epub 2021 Nov 21.
Lithium argyrodites are one of the most promising sulfide electrolytes due to their high ionic conductivity and ductile feature. Among them, Li PS I (LPSI) exhibits better stability against Li metal but a rather low ionic conductivity (only ≈10 S cm ) because of the absence of S /I disorder. Herein, argyrodite Li PS I glass-ceramic electrolytes with high iodine content are synthesized using ultimate-energy mechanical alloying method. S /I disorder is successfully introduced into the system by doping LiI during this one-pot process. Determined by Li magic angle spinning nuclear magnetic resonance and ab initio molecular dynamics simulations, the introduction of iodine promotes Li inter-cage jumps, leading to an enhanced long-range Li conducting. The Li PS I glass-ceramic electrolyte (LPSI -gc) possesses high ionic conductivity (2.04 mS cm ) and excellent stability against Li metal. The Li symmetric cell with the LPSI -gc electrolyte demonstrates ultralong cycling stability over 3200 h at 0.2 mA cm . LiCoO /Li PS Cl/Li all-solid-state battery applying LPSI -gc as the anode interlayer also presents prominent cycling and rate performance. This work provides a novel type of electrolyte with high ionic conductivity and stability against Li metal.
锂硫银锗矿是最具前景的硫化物电解质之一，因其具有高离子电导率和可延展特性。其中，Li₂PS₃I（LPSI）对锂金属表现出较好的稳定性，但由于不存在S/I无序，其离子电导率相当低（仅约10⁻⁵ S cm⁻¹）。在此，采用高能机械合金化方法合成了高碘含量的硫银锗矿Li₂PS₃I玻璃陶瓷电解质。在这一锅法过程中，通过掺杂LiI成功将S/I无序引入该体系。通过锂魔角旋转核磁共振和从头算分子动力学模拟确定，碘的引入促进了锂在笼间的跳跃，导致长程锂传导增强。Li₂PS₃I玻璃陶瓷电解质（LPSI -gc）具有高离子电导率（2.04 mS cm⁻¹）和对锂金属优异的稳定性。采用LPSI -gc电解质的锂对称电池在0.2 mA cm⁻²下展示了超过3200 h的超长循环稳定性。将LPSI -gc用作阳极中间层的LiCoO₂/Li₂PS₃Cl/Li全固态电池也表现出卓越的循环和倍率性能。这项工作提供了一种具有高离子电导率和对锂金属稳定性的新型电解质。
