Advancements in high voltage, high-energy density, lithium-ion cathode materials: A focused review

High-voltage and high-energy-density cathode materials play a pivotal role in advancing lithium-ion battery (LIB) technology, addressing the increasing demand for efficient energy storage in electric vehicles (EVs) and grid-scale applications. This review comprehensively explores cathode materials with operational voltages ranging from 4.5 V to 5.6 V and theoretical capacities between 60.5 mAh/g and 327.2 mAh/g, providing an in-depth analysis of their synthesis methods, electrochemical performance, and structural characteristics. Recent advancements, including surface coatings, bulk doping strategies, and morphology engineering, have significantly enhanced the stability and energy retention of these materials. Computational modeling has emerged as a powerful tool for predicting electrochemical behavior, accelerating material discovery, and optimizing structural modifications. However, key challenges such as capacity fading, cation disorder, and electrolyte compatibility remain obstacles to commercialization. This review also discusses the emergence of new cathode families, including spinels, fluorophosphates, sulfates, and disordered rock-salt oxides, which offer promising high-voltage performance while addressing some of the limitations of traditional layered oxides. The transition toward next-generation cathode materials necessitates the development of high-voltage-compatible electrolytes, enhanced cycle stability, and scalable, cost-effective synthesis techniques. Future innovations in nano-structuring, defect engineering, and hybrid electrolyte systems will be instrumental in overcoming these challenges. In the near future, advancements in high-voltage cathodes are expected to revolutionize LIB technology, extending the driving range of EVs, improving safety, and supporting the global transition toward sustainable energy solutions.