Recent progress and prospects of pitch-based carbon anodes for alkali metal-ion (Li/Na/K) batteries

Abstract

Pitch-based carbon materials (PBCMs) are considered as one of the most promising anodes for alkali metal-ion (Li/Na/K) batteries due to their low cost, high carbon yield, resource availability, and environmental friendliness. However, PBCMs tend to be soft carbon with low layer spacing at high temperatures, resulting in undesirable reversible capacity and poor cycling stability during repeated charging and discharging cycles, which limit their applicability to energy storage systems. To date, many studies have focused on modifying PBCMs to achieve excellent alkali metal-ion storage performance. In this review, the operating mechanisms and corresponding microstructural characteristics of PBCMs used in alkali metal-ion batteries are discussed. Additionally, the design and optimization strategies of PBCMs are summarized and discussed in detail, including morphology adjustment, heteroatom doping, composite modification, pre-oxidation, and coating strategies. Furthermore, the current research status and development prospects of PBCMs are presented, including a perspective on future research directions.