Embossed aluminum as a current collector for high-rate lithium cathode performance

Al foil carefully prepared via an anodization process followed by chromate-phosphate treatment is evaluated for use as a current collector for a cathode powder prepared by the conventional electrode coating method. The formation of an embossed surface on the current collector imparts hydrophilic properties, thereby enhancing the adhesion capabilities of the cathode active material. In Li-ion cells where LiCoO2 is employed as the active cathode material, the embossed Al foil is an electrochemically stable current collector when in contact with other cell components during the charge discharge processes. This also produces a notable decrease in the polarization associated with the electrical disconnection between the active material and the Al current collector, which ultimately results in a stable cycle life at high current densities.