High–Speed electron beam curing of thick electrode for high energy density Li-ion batteries

Abstract

Electron beam curing is demonstrated as a promising method for high speed, low cost and environmentally friendly battery electrode manufacturing. This work reports transfer of this process to pilot scale equipment and evaluation of electrochemical performance in prototype 1.5 Ah pouch cells. Thick LiNi0.5Mn0.3Co0.2O2 (NMC532) composite electrodes with an areal loading of 25 mg cm−2 (∼4 mAh cm−2) are successfully cured at a line speed of 500 feet per minute at 275 keV. Compared to the NMC532 cathode processed via a conventional coating method, the electron beam cured electrodes show higher capacity fade in the first 100 cycles, but similar fade rate afterwards. Further improvement strategies are proposed and discussed. This work demonstrates that electron beam curing is a promising method for manufacturing thick battery electrodes at high speeds and low capital/operation cost. Keywords: Electron beam curing, Li-ion batteries, Thick electrode