Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practic...Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practical application of lithium metal battery(LMB) is largely retarded by the instable interfaces, uncontrolled dendrites, and rapid capacity deterioration. Herein, we present a comprehensive overview towards the working principles and inherent challenges of LMAs. Firstly, we diligently summarize the intrinsic mechanism of Li stripping and plating process. The recent advances in atomic and mesoscale simulations which are crucial in guiding mechanism study and material design are also summarized. Furthermore, the advanced engineering strategies which have been proved effective in protecting LMAs are systematically reviewed, including electrolyte optimization, artificial interface, composite/alloy anodes and so on. Finally, we highlight the current limitations and promising research directions of LMAs. This review sheds new lights on deeply understanding the intrinsic mechanism of LMAs, and calls for more endeavors to realize practical Li metal batteries.展开更多
Solid electrolyte interphase(SEI)has been widely recognized as the most important and the least understood component in lithium batteries.Considering the intrinsic instability in both chemical and mechanical,the failu...Solid electrolyte interphase(SEI)has been widely recognized as the most important and the least understood component in lithium batteries.Considering the intrinsic instability in both chemical and mechanical,the failure of SEI is inevitable and strongly associated with the performance decay of practical working batteries.In this Review,the failure mechanisms and the corresponding regulation strategies of SEI are focused.Firstly,the fundamental properties of SEI,including the formation principles,and the typical composition and structures are briefly introduced.Moreover,the common SEI failure modes involving thermal failure,chemical failure,and mechanical failure are classified and discussed,respectively.Beyond that,the regulation strategies of SEI with respect to different failure modes are further concluded.Finally,the future endeavor in further disclosing the mysteries of SEI is prospected.展开更多
Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactiv...Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactive lithium metal result in the severe safety risks and the short lifespan for highenergy-density rechargeable batteries.Here,we demonstrate a hydrophobic and ionically conductive ethylene-vinyl acetate(EVA)copolymer layer can not only endow lithium metal anodes with an air-stable and anti-water surface,but also efficiently suppress the lithium-dendrites growth during the electrochemical cycling process.Therefore,the introduction of the EVA copolymer as a bifunctional protection layer simultaneously improves the anti-water/air performance and electrochemical cycling stability of lithium metal anode.展开更多
Lithium (Li) metal attributes to the promising anode but endures the low Columbic efficiency (CE) and safety issues from the inactive Li accumulation. The metallic Li which is isolated from the lithium anode (named de...Lithium (Li) metal attributes to the promising anode but endures the low Columbic efficiency (CE) and safety issues from the inactive Li accumulation. The metallic Li which is isolated from the lithium anode (named dead Li^(0)) consists the major component of the inactive Li. We systematically and meticulously investigated the formation and evaluation of dead Li^(0) during stripping process from electron transfer, the oxidation of Li^(0) to Li^(+) and the diffusion of Li^(+) through solid electrolyte interphase (SEI). The above-mentioned processes were regulated by adjusting the contact sites of electron channels, the dynamic rate of conversion from Li^(0) to Li^(+), and the structure as well as components of SEI. The design principles for achieving less dead Li^(0) and higher CE are proposed as a proof of concept in lithium metal batteries. This new insight sheds a comprehensive light on dead Li^(0) formation and guides the next-generation safe batteries for future application.展开更多
A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in p...A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in pouch-type Li metal batteries is probed. The thermal runaway temperatures of Li metal batteries obtained by accelerating rate calorimeter are reduced from 211 ℃ for Li foil to 111 ℃ for cycled Li.The initial exothermic temperature is reduced from 194 ℃ for routine Li foil to 142 ℃ for 49.5 m~2g^(-1) dendrite. Li with different specific surface areas can regulate the reaction routes during the temperature range from 50 to 300 ℃. The mass percent of Li foil and highly dendritic Li reacting with ethylene carbonate is higher than that of moderately dendritic Li. This contribution can strengthen the understanding of the thermal runaway mechanism and shed fresh light on the rational design of safe Li metal batteries.展开更多
基金supported by National Key Research and Development Program (2021YFB2400300)Beijing Natural Science Foundation (JQ20004)+1 种基金the National Natural Science Foundation of China (22109011, U1801257)Scientific and Technological Key Project of Shanxi Province (20191102003)。
文摘Lithium metal anode(LMA) is a promising candidate for achieving next-generation high-energy-density batteries due to its ultrahigh theoretical capacity and most negative electrochemical potential. However, the practical application of lithium metal battery(LMB) is largely retarded by the instable interfaces, uncontrolled dendrites, and rapid capacity deterioration. Herein, we present a comprehensive overview towards the working principles and inherent challenges of LMAs. Firstly, we diligently summarize the intrinsic mechanism of Li stripping and plating process. The recent advances in atomic and mesoscale simulations which are crucial in guiding mechanism study and material design are also summarized. Furthermore, the advanced engineering strategies which have been proved effective in protecting LMAs are systematically reviewed, including electrolyte optimization, artificial interface, composite/alloy anodes and so on. Finally, we highlight the current limitations and promising research directions of LMAs. This review sheds new lights on deeply understanding the intrinsic mechanism of LMAs, and calls for more endeavors to realize practical Li metal batteries.
基金supported by the Beijing Natural Science Foundation(JQ20004,L182021)the National Natural Science Foundation of China(21808124)the National Key Research and Development Program(2016YFA0202500)。
文摘Solid electrolyte interphase(SEI)has been widely recognized as the most important and the least understood component in lithium batteries.Considering the intrinsic instability in both chemical and mechanical,the failure of SEI is inevitable and strongly associated with the performance decay of practical working batteries.In this Review,the failure mechanisms and the corresponding regulation strategies of SEI are focused.Firstly,the fundamental properties of SEI,including the formation principles,and the typical composition and structures are briefly introduced.Moreover,the common SEI failure modes involving thermal failure,chemical failure,and mechanical failure are classified and discussed,respectively.Beyond that,the regulation strategies of SEI with respect to different failure modes are further concluded.Finally,the future endeavor in further disclosing the mysteries of SEI is prospected.
基金supported by the National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019,21808124,51972121)+1 种基金Tip-top Scientific and Technical Innovative Youth Talents of Guangdong Special Support Program(2017TQ04C419)Beijing Natural Science Foundation(L182021)。
文摘Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactive lithium metal result in the severe safety risks and the short lifespan for highenergy-density rechargeable batteries.Here,we demonstrate a hydrophobic and ionically conductive ethylene-vinyl acetate(EVA)copolymer layer can not only endow lithium metal anodes with an air-stable and anti-water surface,but also efficiently suppress the lithium-dendrites growth during the electrochemical cycling process.Therefore,the introduction of the EVA copolymer as a bifunctional protection layer simultaneously improves the anti-water/air performance and electrochemical cycling stability of lithium metal anode.
基金This work was supported by the Beijing Municipal Natural Science Foundation(Z20J00043)the National Natural Science Foundation of China(21825501)+1 种基金the National Key Research and Development Program(2016YFA0202500)the Tsinghua University Initiative Scientific Research Program.
文摘Lithium (Li) metal attributes to the promising anode but endures the low Columbic efficiency (CE) and safety issues from the inactive Li accumulation. The metallic Li which is isolated from the lithium anode (named dead Li^(0)) consists the major component of the inactive Li. We systematically and meticulously investigated the formation and evaluation of dead Li^(0) during stripping process from electron transfer, the oxidation of Li^(0) to Li^(+) and the diffusion of Li^(+) through solid electrolyte interphase (SEI). The above-mentioned processes were regulated by adjusting the contact sites of electron channels, the dynamic rate of conversion from Li^(0) to Li^(+), and the structure as well as components of SEI. The design principles for achieving less dead Li^(0) and higher CE are proposed as a proof of concept in lithium metal batteries. This new insight sheds a comprehensive light on dead Li^(0) formation and guides the next-generation safe batteries for future application.
基金supported by the National Key Research and Development Program(2021YFB2500300)the National Natural Science Foundation of China(22179070,22109084,22075029,and U1932220)+1 种基金the China Postdoctoral Science Foundation(2021TQ0161 and 2021M691709)the Beijing Natural Science Foundation(JQ20004)。
文摘A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in pouch-type Li metal batteries is probed. The thermal runaway temperatures of Li metal batteries obtained by accelerating rate calorimeter are reduced from 211 ℃ for Li foil to 111 ℃ for cycled Li.The initial exothermic temperature is reduced from 194 ℃ for routine Li foil to 142 ℃ for 49.5 m~2g^(-1) dendrite. Li with different specific surface areas can regulate the reaction routes during the temperature range from 50 to 300 ℃. The mass percent of Li foil and highly dendritic Li reacting with ethylene carbonate is higher than that of moderately dendritic Li. This contribution can strengthen the understanding of the thermal runaway mechanism and shed fresh light on the rational design of safe Li metal batteries.
基金This work was supported by National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019)Beijing Natural Science Foundation(L182021).
