Enabling safer, ultralong lifespan all-solid-state Li-organic batteries

Abstract

Organic cathode materials have attracted widespread attention due to their diverse structures, abundant raw materials, low cost, and eco-friendliness. However, their practical applications are restricted because of the poor cycling stability and lifespan owing to the dissolution and shuttle effect of the organic cathode in the liquid electrolyte. In this work, a novel all-solid-state Li-organic battery with ultralong lifespan is developed by using perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as the organic cathode, composite solid polymer electrolyte (hybrid polymer-LiTFSI-LLZTO, HLL) as the electrolyte, and Li metal as the anode. The as-prepared HLL electrolyte exhibits high ionic conductivity (1.46 × 10-4 S cm−1 at 30 °C), superior thermal stability (~202 °C), outstanding electrode/electrolyte interfacial compatibility, and significant suppression to the dissolution/shuttle of PTCDA and the growth of Li dendrite. Ascribing to these advantages, the solid-state PTCDA|HLL|Li battery delivers a reversible capacity of 60 mAh g−1 after 1000 cycles at a high current density of 500 mA g−1, corresponding to an outstanding capacity retention of 91%. Moreover, the solid-state PTCDA|Li battery presents an elevated thermal stable window (178 °C) and less heat release (430 J g−1) compared with the analogous battery using liquid electrolyte (151 °C and 486 J g−1). Furthermore, the solid-state battery exhibits desirable flexibility and satisfactory safety under various abuse conditions (bending, cutting, and punching), demonstrating its outstanding safety in practical environments. This work offers a new pathway toward safer, longer lifespan solid-state Li-organic batteries.