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锂离子电池在便携式电子设备、电动汽车等领域得到了广泛应用,随着对电池能量密度需求的日益增加,高比能、高稳定正极材料的开发成为相关研究的重点和难点.而正极材料比能量的提升又同时伴随着其自身结构稳定性和循环稳定性的挑战,使得锂离子电池的稳定性、安全性成为制约其应用的关键挑战.本文以高比能正极材料为研究对象,对影响正极材料结构稳定性、电化学稳定性等一系列因素进行介绍和分析,再从目前改善材料结构稳定性的有效策略入手,对表面限域掺杂这一特殊稳定策略的实现途径、稳定机制进行了总结和分析,并结合现有不同表面修饰方法进行分析和评述,对高比能正极稳定性提升的可能策略及方向进行了展望.“,”Lithium ion batteries(LIBs)have broad applications in a wide variety of a fields pertaining to energy storage devices.In line with the increasing demand in emerging areas such as long-range electric vehicles and smart grids,there is a continuous effort to achieve high energy by maximizing the reversible capacity of electrode materials,particularly cathode materials.However,in recent years,with the continuous enhancement of battery energy density,safety issues have increasingly attracted the attention of researchers,becoming a non-negligible factor in determining whether the electric vehicle industry has a foothold.The key issue in the development of battery systems with high specific energies is the intrinsic instability of the cathode,with the accompanying question of safety.The failure mechanism and stability of high-specific-capacity cathode materials for the next generation of LIBs,including nickel-rich cathodes,high-voltage spinel cathodes,and lithium-rich layered cathodes,have attracted extensive research attention.Systematic studies related to the intrinsic physical and chemical properties of different cathodes are crucial to elucidate the instability mechanisms of positive active materials.Factors that these studies must address include the stability under extended electrochemical cycles with respect to dissolution of metal ions in LiPF6-based electrolytes due to HF corrosion of the electrode;cation mixing due to the similarity in radius between Li+and Ni2+;oxygen evolution when the cathode is charged to a high voltage;the origin of cracks generated during repeated charge/discharge processes arising from the anisotropy of the cell parameters;and electrolyte decomposition when traces of water are present.Regulating the surface nanostructure and bulk crystal lattice of electrode materials is an effective way to meet the demand for cathode materials with high energy density and outstanding stability.Surface modification treatment of positive active materials can slow side reactions and the loss of active material,thereby extending the life of the cathode material and improving the safety of the battery.This review is targeted at the failure mechanisms related to the electrochemical cycle,and a synthetic strategy to ameliorate the properties of cathode surface locations,with the electrochemical performance optimized by accurate surface control.From the perspective of the main stability and safety issues of high-energy cathode materials during the electrochemical cycle,a detailed discussion is presented on the current understanding of the mechanism of performance failure.It is crucial to seek out favorable strategies in response to the failures.Considering the surface structure of the cathode in relation to the stability issue,a newly developed protocol,known as surface-localized doping,which can exist in different states to modify the surface properties of high-energy cathodes,is discussed as a means of ensuring significantly improved stability and safety.Finally,we envision the future challenges and possible research directions related to the stability control of next-generation high-energy cathode materials.