Improvement in Rate Capabilities of Hybrid Cathodes with Through‐Holed Layers of Cathode Material and Activated Carbon on Each Side of a Current Collector in Lithium‐Ion Batteries.

Abstract

This study was conducted to improve the rate capability and cyclability of cathodes for lithium‐ion batteries (LIBs) with a hybrid cathode structure. The through‐holed LIB cathode material and activated carbon layers formed on each side of a current collector were drilled with a picosecond pulsed laser beam to prepare the cathode structure. The hybrid cathodes exhibited excellent rate capabilities of 93 % capacity retention at 100 C. The results were dependent on the weight percentage of the activated carbon relative to the total weight of the active materials and on the difference in discharge/charge voltages between the LIB cathode and activated carbon materials. The cathode had cycle stability at 50 C during 100 cycles. The performance characteristics of the hybrid cathode, the through‐holed and nontreated LIB cathodes, and the nontreated activated carbon cathodes were compared. In the Ragone plot, the hybrid cathode was located in the region where conventional through‐holed and nontreated cathodes would not be located.