Investigating dopants to improve sintered LiMn2O4 spinel electrode electrochemical cycling limitations

Lithium-ion batteries have become prevalent for portable energy storage. Towards continuing to increase the energy density of batteries, engineering the electrode structure can provide improvements with regards to energy and power density. Sintered electrodes, which have no inactive additives, can achieve high areal loadings of over 150 mg electroactive material cm(-2), however, they have electronic and/or ionic transport resistance limitations as the electrode loadings and thicknesses increase. Herein, LiMn2O4 was investigated as a sintered electrode cathode material. LiMn2O4 is attractive as a relatively low cost and Co-free cathode option, but its relatively low electronic conductivity and fading due to Jahn-Teller distortion and/or manganese dissolution pose challenges that are exacerbated in sintered electrodes relative to composites. Thus the incorporation of dopants LiMn2-xMxO4, where M = Cu or Al (in isolation or combination) and x ranged from 0 to 0.15, were investigated to understand how modifications to the material electronic conductivity and structural stability would impact sintered electrodes comprised of these materials. Improvement in sintered electrode electrochemical outcomes was observed for incorporation of both dopants. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

To increase the energy and power density of batteries, engineering the electrode structure can provide improvements. Sintered electrodes can achieve high areal loadings, but may face electronic and/or ionic transport limitations as loadings and thicknesses increase.