Y.X. Ma ‡, D.K. Jin ‡, H.D. Shi *, R. Li, Y.T. Niu, Y.Y. Xu, C. Dong, Y.Y. Liu, R. Yang, G.M. Zhong, C.Y. Wang, Z.Z. Zhang, Z.Q. Peng and Z.-S. Wu *

ACS Energy Letters, 2025, 10.

DOI: 10.1021/acsenergylett.4c03115 [PDF]

Li6PS5I based solid-state electrolytes (SSEs) show promising interface compatibility for all-solid-state batteries (ASSBs), but still suffer from limited ionic conductivity. Herein, a superionic conductor lithium argyrodite sulfide, Li7-x(GeSi)(1-x)/2SbxS5I, was developed by multi-cation substitution of Ge, Si, and Sb for P, increasing configurational entropy of the Li6PS5I. This approach enhanced Li+ content and anion site disorder, leading to a low activation energy of 0.17 eV for Li+ migration, and consequently a high cold-pressed ionic conductivity of 12.7 mS cm-1, and a record value of 32.2 mS cm-1 after hot-pressing. When incorporating Li3InCl6 as the catholyte and interlayer, the LiNi0.8Co0.1Mn0.1O2@Li3InCl6|Li3InCl6|Li20/3(GeSiSb)1/3S5I|Li-In ASSBs exhibited a high capacity of 219 mAh g-1 at 0.1 C, and a notable capacity of 135 mAh g-1 with 84.4% retention at 1 C after 550 cycles. Our ASSBs attained stable cycling across -20 to 60 °C, and operated well at an ultrahigh cathode loading of 100 mg cm-2. These findings advance sulfide SSEs in high-performance and wide-temperature ASSBs.