硅酸盐学报2025，Vol.53Issue(6)：1764-1776,13.DOI:10.14062/j.issn.0454-5648.20250145
固态电池富锂锰基层状氧化物正极材料研究进展
Li-Rich Mn-Based Layered Oxide Cathodes for Solid-State Rechargeable Batteries
摘要
Abstract
Solid-state batteries(SSBs)are a promising next-generation secondary battery due to their potential for high energy density and enhanced safety,offering solutions to the problems inherent in conventional lithium-ion batteries(LIBs)with organic liquid electrolytes(i.e.,flammability,corrosion susceptibility,and high-voltage instability).In the construction of SSBs,the selection of the cathode materials is critical to achieving a high energy density,particularly when coupled with lithium metal anodes.However,conventional cathodes often affect the energy density of SSBs due to their constrained specific capacities.It is thus crucial for achieving substantial improvements in the energy density of SSBs to develop high specific capacity cathodes.The Li-rich Mn-based layered oxide(LRMO)is a promising cathode material for SSBs for energy densities of above 600 W·h·kg-1 due to their high discharge specific capacities.Furthermore,LRMO cathodes offer some additional advantages,i.e.,reduction of Co and Ni content,leverage of the abundance of Mn to achieve lower materials costs and improved safety.Their application in SSBs also mitigates the dissolution of TM-ions into the electrolyte,thereby enhancing the structural stability and capacity retention during long-term cycling progress.In addition,the resource-efficient composition of LRMO cathodes also align with environmentally friendly and sustainable development goals. This review represents that the LRMO cathode materials are characterized by a composite crystal structure comprising two key components,i.e.,Li2MnO3 phase and LiMO2(M=Mn,Ni,Co)phase.Li2MnO3 phase can be considered as a superlattice-structured variant of LiMO2,formulated as Li[LixMn1-x]O2.This superlattice-structured introduces unique unhybridized O 2p states,arising from Li—O—Li configurations.These unique oxygen states enable the participation of oxygen in charge compensation processes.Consequently,the high capacity in LRMO cathodes is attributed to the synergistic contributions of both TM cations and oxygen redox reactions. LRMO cathodes,while exhibiting a distinctive biphasic structure,encounter significantly some challenges in SSBs.Specifically,the application of LRMO cathodes in SSBs is hindered by two primary issues.Firstly,the inherent incompatibility between Li2MnO3 phase and SEs interfaces results in sluggish reaction kinetics,severely restricting the activation of oxygen redox activity and consequently reducing the associated capacity contribution.Secondly,a chemical potential mismatch between SEs and LRMO cathodes drives spontaneous reactions at the composite cathode interfaces.These reactions lead to the formation of mixed ionic/electronic conductive CEI.Furthermore,irreversible oxygen escape further oxidizes the SEs interface,generating the passivation layers.These passivation layers increase interfacial impedance and imped ion transport,ultimately hindering practical advancements in SSBs technology. LRMO cathodes hold a significant promise for SSBs,as evidenced by research progress across various SEs,including sulfides,halides,polymers,and oxides.To fully realize this potential,some strategies addressing the inherent incompatibility between LRMO cathodes and SEs are crucial.These strategies encompass bulk/interfacial structure design,nanostructured particle engineering,and the construction of stable Li+/e-transport pathways.These approaches can suppress oxygen escape,enhance the high-voltage stability of solid-solid interfaces,and ultimately stabilize oxygen redox while optimizing interfacial dynamics.Consequently,the implementation of these strategies leads to a significant enhancement in the electrochemical performance of LRMO-based SSBs. Summary and prospects LRMO cathodes have attracted considerable attention for SSBs due to their high discharge specific capacity and energy density.Advancements in SSBs utilizing sulfide,halide,polymer,and oxide SEs demonstrate a potential of LRMO cathodes to overcome limitations currently hindering their industrial applications in liquid electrolyte systems.These limitations include gas evolution,TM dissolution,and voltage decay.However,the practical application of LRMO cathodes in SSBs faces some challenges stemming from their inherent properties,such as poor electronic conductivity attributed to their biphasic structure,sluggish interfacial charge transfer kinetics,oxygen escape,high-voltage interfacial instability,and electrochemical-mechanical degradation.Consequently,a comprehensive understanding of failure mechanisms and the development of advanced modification strategies for LRMO cathodes in SSBs are urgently needed.This necessitates several key research directions.Firstly,optimizing large-scale synthesis techniques for single-crystal LRMO cathodes is crucial,coupled with systematic investigation into their degradation mechanisms within SSBs.Such studies should elucidate the complex interplay of mechanical,electrical,and chemical coupling within SSBs.Secondly,the development of zero-strain LRMO cathodes,designed to maintain structural integrity with minimal volume changes during cycling,can effectively mitigate mechanical stress,suppress crack formation(both intergranular and intragranular),and significantly improve long-term cycling stability.Furthermore,machine learning-driven multiscale modeling offers an effective tool for the rational design of bulk/interfacial structures,facilitating superior compatibility and high-voltage stability at the solid-solid interfaces.Finally,the exploration of high-voltage-tolerant SEs specifically tailored for LRMO cathodes,alongside innovations in scalable fabrication processes for ultrathin electrolyte membranes and electrode films,is essential.The synergistic convergence of materials innovation,interfacial engineering and scalable manufacturing offers a transformative potential for realizing the full capabilities of LRMO cathodes.This convergence is crucial for advancing SSBs toward unprecedented levels of energy density,reliability and sustainability.Specifically,these combined efforts will facilitate the production of large-format batteries at the A·h-level,ultimately enabling the large-scale commercialization of SSBs incorporating LRMO cathodes.关键词
固态电池/富锂锰基正极材料/能量密度/阴离子氧化还原反应/高电压界面Key words
solid-state batteries/lithium-rich manganese-based cathode materials/energy density/oxygen redox/high-voltage interface分类
动力与电气工程引用本文复制引用
孔伟进,沈亮,赵辰孜,乐翼成,顾一凡,胡江奎,张强..固态电池富锂锰基层状氧化物正极材料研究进展[J].硅酸盐学报,2025,53(6):1764-1776,13.基金项目
国家重点研发计划(2021YFB2500300) （2021YFB2500300）
国家自然科学基金(22409113,22393904,22393900,22393903) （22409113,22393904,22393900,22393903）
中国博士后科学基金面上项目(2023M731864) （2023M731864）
华能集团科技项目(HNKJ23-H71) （HNKJ23-H71）
清华大学自主科研经费 （）
新基石科学基金会 （）
清华大学"水木学者"资助计划. （）
