An Overview on the Advances of LiCoO₂ Cathodes for Lithium‐Ion Batteries

TLDR

LiCoO₂, discovered in 1980, remains the dominant cathode for portable electronics because of its high density, energy density, cycle life, and reliability, yet raising its cutoff voltage above 4.2 V to meet energy demands introduces surface degradation, phase‑transition damage, and inhomogeneous reactions that accelerate capacity loss. This review surveys the history and recent advances of LiCoO₂, with a dedicated section on its fundamental failure mechanisms at voltages above 4.2 V. The authors discuss industry‑level modification strategies and developments for LiCoO₂‑based LIBs to mitigate high‑voltage degradation.

Abstract

Abstract LiCoO 2 , discovered as a lithium‐ion intercalation material in 1980 by Prof. John B. Goodenough, is still the dominant cathode for lithium‐ion batteries (LIBs) in the portable electronics market due to its high compacted density, high energy density, excellent cycle life and reliability. In order to satisfy the increasing energy demand of portable electronics such as smartphones and laptops, the upper cutoff voltage of LiCoO 2 ‐based batteries has been continuously raised for achieving higher energy density. However, several detrimental issues including surface degradation, damages induced by destructive phase transitions, and inhomogeneous reactions could emerge as charging to a high voltage (>4.2 V vs Li/Li + ), which leads to the rapid decay of capacity, efficiency, and cycle life. In this review, the history and recent advances of LiCoO 2 are introduced, and a significant section is dedicated to the fundamental failure mechanisms of LiCoO 2 at high voltages (>4.2 V vs Li/Li + ). Meanwhile, the modification strategies and the development of LiCoO 2 ‐based LIBs in industry are also discussed.