Direct carbon-black coating on LiCoO 2 cathode using surfactant for high-density Li-ion cell

Abstract

Direct carbon-black coating of the cathode material using a surfactant increases the capacity of a Li-ion cell by ∼10% compared with using bare LiCoO 2. The coating method comprises two steps: (i) dispersion of aggregated carbon black using orotan ®—a polyacrylate dispersant; (ii) carbon-black coating of the cathode material using a gelatin—an amphoteric surfactant. This technology reduces the carbon content in the electrode without sacrificing the cycle-life performance of the cell, and also improves the rate capability of the Li-ion cell. Moreover, the direct carbon-black-coated cathode exhibits excellent capacity recovery and restricted expansion of the cell thickness compared with a bare cathode during storage at 85 °C.