1. Rapid Thermal Shutdown of Deep-Eutectic-Polymer Electrolyte Enabling Overheating Self-Protection of Lithium Metal Batteries.
- Author
-
Zhang Z, Li G, Du X, Huang L, Kang G, Zhang J, Cui Z, Liu T, Ni L, Jin Y, and Cui G
- Abstract
Safety concerns and uncontrollable dendrite growths have severely impeded the advancement of lithium-metal batteries. Herein, a safe deep-eutectic-polymer electrolyte with built-in thermal shutdown capability is proposed by utilizing hydrophobic association of methylcellulose within a novel deep-eutectic-solvent. Specifically, at elevated temperatures, methylcellulose chains aggregate to form dense polymer networks due to hydrophobic association and break the solvation structure equilibrium inside the deep-eutectic system through encapsulating Li
+ in polymer matrix, leading to quick solidification of the electrolyte. The solidified electrolyte obstructs Li+ transports and terminates electrochemical processes, protecting LMBs from unstoppable exothermic chain reactions. The accelerating rate calorimeter tests of 1 Ah pouch cells demonstrate that the as-prepared electrolyte significantly improves the onset self-heating temperature from 73 °C for conventional electrolytes to 172 °C and prolongs the thermal runaway waiting time more than 20 hours. More impressively, benefiting from its favorable electrochemical performance, this polymer electrolyte enables LiNi0.8 Mn0.1 Co0.1 O2 ||Li batteries to retain 92% capacity over 200 cycles and LiFePO4 ||Li batteries to maintain 90% capacity after 500 cycles. This research paves a promising avenue for enhancing both the safety and electrochemical performance of high-energy-density LMBs., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)- Published
- 2024
- Full Text
- View/download PDF