Three-dimensional conductive network formed by carbon nanotubes in aqueous processed NMC electrode

Aqueous processing of lithium nickel manganese cobalt oxide (LiNi0.5Mn0.3Co0.2O2, NMC 532) cathodes was investigated by incorporating carbon nanotubes (CNTs) as the conductive additive. Morphology observation showed CNTs evenly disperse across the electrode, uniformly covering each primary particle, and form three-dimensional electronic pathways. A resistance measurement indicated the CNTs can improve the electronic conductivity of the composite electrode by an order of magnitude compared to carbon black. CNTs based electrodes showed higher rate performance, lower hysteresis, and better cycling performance with 99.4% capacity retention after 200 cycles in full pouch cells compared to 94.6% for carbon black based electrode. Meanwhile, the content of active materials in the electrode was increased from 90 wt% to 96 wt% and the energy density was increased by 11.7%. This research demonstrates an effective combined approach for achieving aqueous processed cathodes with enhanced durability while simultaneously achieving higher energy density by reducing the content of inactive components. (c) 2018 Elsevier Ltd. All rights reserved.