Traditional pyrometallurgy and hydrometallurgy processes primarily focus on the recovery of valuable metals(Co,Ni,etc.)from spent lithium-ion batteries.However,these methods are not economical for recycling cheap LiFe...Traditional pyrometallurgy and hydrometallurgy processes primarily focus on the recovery of valuable metals(Co,Ni,etc.)from spent lithium-ion batteries.However,these methods are not economical for recycling cheap LiFePO_(4).Herein,a synergistic thermal-decomposition and electric-drive strategy is proposed to recover the whole spent LiFePO_(4)electrode by in-situ recovering the inactive lithium(dead lithium and trapped interlayer lithium).Firstly,the organic components in the dense solid electrolyte interface(SEI)are effectively decomposed through thermal-decomposition processing,exposing the dead lithium encapsulated within the SEI and recovering the electron channels between the dead lithium and graphite.Leveraging the difference between the Gibbs free energy of the dead lithium and graphite as the driving force facilitates the dead lithium inserting into the anode.Then,fully utilizing the remaining discharge capacity of the spent LiFePO_(4)cell,the inactive lithium is reinserted into LiFePO_(4)lattice during the electric-drive process.Consequently,the reactivated lithium content increases by more than 16%,reaching a capacity of 134.2 mA h g^(-1)compared to 115.2 mA h g^(-1)from degraded LiFePO_(4),allowing for effective participation in the subsequent cycling.This work provides new perspectives on highly profitable cycles with low energy and material consumption and a low carbon footprint.展开更多
Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of e...Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of easy electrode collapse due to large volume expansion during charge and discharge and low active materials utilization caused by the severe shuttle effect of lithium polysulfides(LiPSs).Therefore,in this work,ramie gum(RG)was extracted from ramie fiber degumming liquid and used as the functional binder to address the above problems and improve the Li-S battery’s performance for the first time.Surprisingly,the sulfur cathode using RG binder illustrates a high initial capacity of 1152.2 mAh/g,and a reversible capacity of 644.6 mAh/g after 500 cycles at 0.5 C,far better than the sulfur cathode using polyvinylidene fluoride(PVDF)and sodium carboxymethyl cellulose(CMC)binder.More importantly,even if the active materials loading increased to as high as 4.30 mg/cm^(2),the area capacity is still around 3.1 mAh/cm^(2)after 200 cycles.Such excellent performances could be attributed to the abundant oxygen-and nitrogen-containing functional groups of RG that can effectively inhibit the shuttle effect of LiPSs,as well as the excellent viscosity and mechanical properties that can maintain electrode integrity during long-term charging/discharging.This work verifies the feasibility of RG as an eco-friendly and high-performance Li-S battery binder and provides a new idea for the utilization of agricultural biomass resources.展开更多
High-nickel cathode LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)could enable lithium-ion batteries(LIBs)with high energy density.However,excessive decomposition of the electrolyte would happen in the high operating voltage...High-nickel cathode LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)could enable lithium-ion batteries(LIBs)with high energy density.However,excessive decomposition of the electrolyte would happen in the high operating voltage range.In addition,the utilization of flammable organic solvents would increase safety risks in the high temperature environment.Herein,an electrolyte consisting of flame-retardant solvents with lower highest occupied molecular orbital(HOMO)level and LiDFOB salt is proposed to address above two issues.As a result,a thin and robust cathode-electrolyte interface containing rich LiF and Li-B-O compounds is formed on the cathode to effectively suppress electrolyte decomposition in the high operating voltage.The NCM811||Li cell paired with this designed electrolyte possesses a capacity retention of 72%after 300 cycles at 55℃.This work provides insights into developing electrolyte for stable high-nickel cathode operated in the high temperature.展开更多
The shortage of fresh water in the world has brought upon a serious crisis to human health and economic development.Solar‐driven interfacial photothermal conversion water evaporation including evaporating seawater,la...The shortage of fresh water in the world has brought upon a serious crisis to human health and economic development.Solar‐driven interfacial photothermal conversion water evaporation including evaporating seawater,lake water,or river water has been recognized as an environmentally friendly process for obtaining clean water in a low‐cost way.However,water transport is restricted by itself by solar energy absorption capacity's limits,especially for finite evaporation rates and insufficient working life.Therefore,it is important to seek photothermal conversion materials that can efficiently absorb solar energy and reasonably design solar‐driven interfacial photothermal conversion water evaporation devices.This paper reviews the research progress of carbon‐based photothermal conversion materials and the mechanism for solar‐driven interfacial photothermal conversion water evaporation,as well as the summary of the design and development of the devices.Based on the research progress and achievements of photothermal conversion materials and devices in the fields of seawater desalination and photothermal electric energy generation in recent years,the challenges and opportunities faced by carbon‐based photothermal conversion materials and devices are discussed.The prospect of the practical application of solar‐driven interfacial photothermal conversion evaporation technology is foreseen,and theoretical guidance is provided for the further development of this technology.展开更多
Uniform lithium(Li)deposition in all-solid-state Li metal batteries is greatly influenced by the anode/electrolyte interface.Herein,a Mg-modified interface was constructed via the simple in-situ electrochemical reduct...Uniform lithium(Li)deposition in all-solid-state Li metal batteries is greatly influenced by the anode/electrolyte interface.Herein,a Mg-modified interface was constructed via the simple in-situ electrochemical reduction of Mg^(2+)from Mg(TFSI)_(2) in polyethylene oxide(PEO)and a Li bis(trifluoromethane)sulfoni mide(Li TFSI)formulae.As confirmed by cryogenic transmission electron microscopy,the anode/electrolyte interface exhibited hybrids consisting of crystalline Mg,Li_(2)O,and Li dots embedded in an amorphous polymer electrolyte.The crystalline Mg dots guided the uniform Li nucleation and growth,inducing a smoother anode/electrolyte interface compared with the pristine electrolyte.With 1 wt%Mg(TFSI)_(2) in the PEO-Li TFSI electrolyte,the Mg-modified electrolyte enabled the Li/Li symmetric cells with cycling performance of over 1700 and 1400 h at current densities of 0.1 and 0.2 m A cm^(-2),respectively.Moreover,the full LFP/Li cells using the novel Mg-modified electrolyte delivered a cycling lifespan of over 450 cycles with negligible capacity loss.展开更多
All-solid-state lithium(Li)metal batteries(ASSLMBs)are considered one of the most promising secondary batteries due to their high theoretical capacity and high safety performance.However,low room-temperature ionic con...All-solid-state lithium(Li)metal batteries(ASSLMBs)are considered one of the most promising secondary batteries due to their high theoretical capacity and high safety performance.However,low room-temperature ionic conductivity and poor interfacial stability are two key factors affecting the practical application of ASSLMBs,and our understanding of the mechanisms behind these key problems from microscopic perspective is still limited.In this review,the mechanisms and advanced characterization techniques of ASSLMBs are summarized to correlate the microstructures and properties.Firstly,we summarize the challenges faced by solid polymer electrolytes(SPEs)in ASSLMBs,such as the low roomtemperature ionic conductivity and the poor interfacial stability.Secondly,several typical improvement methods of polymer ASSLMBs are discussed,including composite SPEs,ultra-thin SPEs,SPEs surface modification and Li anode surface modification.Finally,we conclude the characterizations for correlating the microstructures and the properties of SPEs,with emphasis on the use of emerging advanced techniques(e.g.,cryo-transmission electron microscopy)for in-depth analyzing ASSLMBs.The influence of the microstructures on the properties is very important.Until now,it has been difficult for us to understand the microstructures of batteries.However,some recent studies have demonstrated that we have a better understanding of the microstructures of batteries.Then we suggest that in situ characterization,nondestructive characterization and sub-angstrom resolution are the key technologies to help us further understand the batteries'microstructures and promote the development of batteries.And potential investigations to understand the microstructures evolution and the batteries behaviors are also prospected to expect further reasonable theoretical guidance for the design of ASSLMBs with ideal performance.展开更多
On account of the high theoretical capacity, high corrosion resistance, environmental benignity, abundant availability and low cost, the research on a-Fe_2O_3 has been gradually fastened on as promising anodes materia...On account of the high theoretical capacity, high corrosion resistance, environmental benignity, abundant availability and low cost, the research on a-Fe_2O_3 has been gradually fastened on as promising anodes materials toward lithium-ion batteries(LIBs). A high-performance anode for LIBs based on α-Fe_2O_3 nanoplates have been selectively prepared. The α-Fe_2O_3 nanoplates can be synthesized with iron ionbased ionic liquid as iron source and template. The α-Fe_2O_3 nanoplates as the anode of LIBs can display high capacity of around1950 mAh g^(-1) at 0.5 A g^(-1) which have exceeded the theoretical capacity of α-Fe_2O_3. On account of unique nanoplate structures and gum arabic as binder, the α-Fe_2O_3 nanoplates also exhibit high rate capability and excellent cycling performance.展开更多
In order to solve the problem of poor conductivity of traditional LiFePO_(4)cathode binders,we developed sodium alginate-Congo red copolymers(SA-CR)as water-soluble electrically conductive and mechanically robust comp...In order to solve the problem of poor conductivity of traditional LiFePO_(4)cathode binders,we developed sodium alginate-Congo red copolymers(SA-CR)as water-soluble electrically conductive and mechanically robust composite binder.Unlike most other electrically conductive polymer binders,the procedure is straightforward and low-cost to prepare SA-CR binder.Various SA-CR copolymers were prepared with different degree of compounding of CR to investigate the effect of CR on the electrochemical and physical properties of the prepared electrodes.The copolymer whose composition was filled with a mixture of SA and CR at a 3:1 mass ratio showed the best cell performance,due to the well-balanced electrical conductivity and mechanical properties.It exhibited a specific capacity of 118.8 m Ah/g at the 100th cycle with 92.1%capacity retention,significantly better than the 108.5 m Ah/g of conventional acetylene black electrodes.CR as a conduction-promoting agent in water-soluble composite binder favors the formation of continuous and homogenous conducting bridges throughout the electrode and increases the compaction density of electrode by reducing the conducting agent content of acetylene black and thus the improvement of electrode performance is realized.展开更多
Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applicat...Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applications.Herein,a perovskite LiTaO_(3) strengthening network along the grain boundaries is designed to enhance the mechanical and structural stability of polycrystalline LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) by suppressing the anisotropic volume variation and retard the internal strain.Notably,the perovskite-modified LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode material exhibits significantly improved cyclability and rate capacity.Such enhanced electrochemical behavior can be ascribed not merely to the compacted particle,where the LiTaO_(3) interface effectively inhibits electrolyte infiltration,but also to the structural stability in terms of inhibiting lattice oxygen release through the introduction of strong Ta-O bonds,thereby restraining interfacial side reactions and surface phase transitions.This work provides precise control over grain boundaries to suppress the inter-strain,taking care of the crystal structure and interface properties.展开更多
Sodium(Na)ion batteries(SIBs)promise low-cost energy storage systems but are still restricted by insufficient energy density.Introducing oxygen(O)redox into the design of the Na-storage cathode is presently considered...Sodium(Na)ion batteries(SIBs)promise low-cost energy storage systems but are still restricted by insufficient energy density.Introducing oxygen(O)redox into the design of the Na-storage cathode is presently considered an effective avenue to generate extra capacity in solving the energy density bottleneck.The succeeding issues are how to overcome the irreversible electrochemical behavior accompanied by O release.Meanwhile,the O redox chemistry and subsequent structural evolution remain ambiguous so far.Here,we deliberate on the O redox mechanism in Na-storage transition metal oxides.Challenges associated with the reaction irreversibility and structural collapse are summarized by virtue of the advanced characterization techniques.Beyond that,strategies that potentially enhance the electrochemical properties of O redox and future research perspectives on exploring useable O redox cathode materials are outlined.展开更多
Lithium-ion batteries(LIBs)have been in a dominant position in the new energy industry because of their excellent comprehensive performance.The performance of LIBs highly depends on the microstructures of the material...Lithium-ion batteries(LIBs)have been in a dominant position in the new energy industry because of their excellent comprehensive performance.The performance of LIBs highly depends on the microstructures of the materials that constitute LIBs.Particularly,the relatively“weak”molecular interactions instead of the common-discussed strong chemical-bonding always affect the structures and the consequent properties of the components in LIBs.As a typical example,the hydrogen bonds,which widely exist inside LIBs,greatly improved the mechanical strength,lithium ion(Li^(+))transport rate and the intrinsic stabilities towards boosting performance of LIBs.This review starts from the interaction force between molecules,and especially summarizes the correlation between the formation of hydrogen bonds and the properties of the typical components in LIBs(cathode,anode,electrolyte,separator).In addition,how the formation of hydrogen bonds affects the performance of LIBs components is discussed.Finally,the strategies of combining hydrogen bonds with LIBs components in the future are prospected,which provide guidance for the rational design of high-performance LIBs.展开更多
基金supported by the Key Technologies R&D Program of Xiamen(No.3502Z20231057)the Natural Science Foundation of Fujian Province,China(No.2024J011210,No.2021J011214,No.2021J01685)+5 种基金the High-Level Talent Start-Up Foundation of Xiamen Institute of Technology for financial support(No.YKJ23017R)the Industry Leading Key Projects of Fujian Province(No.2022H0057)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(2020R01002)the Fujian Young and Middle-aged Teachers Teacher Education Research Project(Science and Technology)(No.JAT200461)2023 Xiamen Overseas Students Scientific Research Project(Start-up)the National Natural Science Foundation of China(No.21975212,No.22101242,No.52002352,No.52071295)。
文摘Traditional pyrometallurgy and hydrometallurgy processes primarily focus on the recovery of valuable metals(Co,Ni,etc.)from spent lithium-ion batteries.However,these methods are not economical for recycling cheap LiFePO_(4).Herein,a synergistic thermal-decomposition and electric-drive strategy is proposed to recover the whole spent LiFePO_(4)electrode by in-situ recovering the inactive lithium(dead lithium and trapped interlayer lithium).Firstly,the organic components in the dense solid electrolyte interface(SEI)are effectively decomposed through thermal-decomposition processing,exposing the dead lithium encapsulated within the SEI and recovering the electron channels between the dead lithium and graphite.Leveraging the difference between the Gibbs free energy of the dead lithium and graphite as the driving force facilitates the dead lithium inserting into the anode.Then,fully utilizing the remaining discharge capacity of the spent LiFePO_(4)cell,the inactive lithium is reinserted into LiFePO_(4)lattice during the electric-drive process.Consequently,the reactivated lithium content increases by more than 16%,reaching a capacity of 134.2 mA h g^(-1)compared to 115.2 mA h g^(-1)from degraded LiFePO_(4),allowing for effective participation in the subsequent cycling.This work provides new perspectives on highly profitable cycles with low energy and material consumption and a low carbon footprint.
基金supported by the National Natural Science Foundation of China(Nos.51902036,52071295,52002352)Natural Science Foundation of Chongqing Science&Technology Commission(Nos.cstc2019jcyj-msxm1407 and CSTB2022NSCQ-MSX0828)+2 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(No.CX2021046)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJZDK202300802)Research Project of Innovative Talent Training Engineering Program of Chongqing Primary and Secondary School(No.CY230801).
文摘Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of easy electrode collapse due to large volume expansion during charge and discharge and low active materials utilization caused by the severe shuttle effect of lithium polysulfides(LiPSs).Therefore,in this work,ramie gum(RG)was extracted from ramie fiber degumming liquid and used as the functional binder to address the above problems and improve the Li-S battery’s performance for the first time.Surprisingly,the sulfur cathode using RG binder illustrates a high initial capacity of 1152.2 mAh/g,and a reversible capacity of 644.6 mAh/g after 500 cycles at 0.5 C,far better than the sulfur cathode using polyvinylidene fluoride(PVDF)and sodium carboxymethyl cellulose(CMC)binder.More importantly,even if the active materials loading increased to as high as 4.30 mg/cm^(2),the area capacity is still around 3.1 mAh/cm^(2)after 200 cycles.Such excellent performances could be attributed to the abundant oxygen-and nitrogen-containing functional groups of RG that can effectively inhibit the shuttle effect of LiPSs,as well as the excellent viscosity and mechanical properties that can maintain electrode integrity during long-term charging/discharging.This work verifies the feasibility of RG as an eco-friendly and high-performance Li-S battery binder and provides a new idea for the utilization of agricultural biomass resources.
基金supported by the National Key Research and Development Program of China(2022YFB3803400)。
文摘High-nickel cathode LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)could enable lithium-ion batteries(LIBs)with high energy density.However,excessive decomposition of the electrolyte would happen in the high operating voltage range.In addition,the utilization of flammable organic solvents would increase safety risks in the high temperature environment.Herein,an electrolyte consisting of flame-retardant solvents with lower highest occupied molecular orbital(HOMO)level and LiDFOB salt is proposed to address above two issues.As a result,a thin and robust cathode-electrolyte interface containing rich LiF and Li-B-O compounds is formed on the cathode to effectively suppress electrolyte decomposition in the high operating voltage.The NCM811||Li cell paired with this designed electrolyte possesses a capacity retention of 72%after 300 cycles at 55℃.This work provides insights into developing electrolyte for stable high-nickel cathode operated in the high temperature.
基金Natural Science Foundation of Shandong Province,Grant/Award Number:ZR2019MB019National Natural Science Foundation of China,Grant/Award Numbers:22075122,52071295Research Foundation for Talented Scholars of Linyi University,Grant/Award Number:Z6122010。
文摘The shortage of fresh water in the world has brought upon a serious crisis to human health and economic development.Solar‐driven interfacial photothermal conversion water evaporation including evaporating seawater,lake water,or river water has been recognized as an environmentally friendly process for obtaining clean water in a low‐cost way.However,water transport is restricted by itself by solar energy absorption capacity's limits,especially for finite evaporation rates and insufficient working life.Therefore,it is important to seek photothermal conversion materials that can efficiently absorb solar energy and reasonably design solar‐driven interfacial photothermal conversion water evaporation devices.This paper reviews the research progress of carbon‐based photothermal conversion materials and the mechanism for solar‐driven interfacial photothermal conversion water evaporation,as well as the summary of the design and development of the devices.Based on the research progress and achievements of photothermal conversion materials and devices in the fields of seawater desalination and photothermal electric energy generation in recent years,the challenges and opportunities faced by carbon‐based photothermal conversion materials and devices are discussed.The prospect of the practical application of solar‐driven interfacial photothermal conversion evaporation technology is foreseen,and theoretical guidance is provided for the further development of this technology.
基金financial support from the National Natural Science Foundation of China(Grant no.51722210,51972285,U1802254,11904317,and 21902144)the Natural Science Foundation of Zhejiang Province(Grant no.LY17E020010 and LD18E020003)the Innovation Fund of the Zhejiang Kechuang New Materials Research Institute(Grant no.ZKN-18P05)。
文摘Uniform lithium(Li)deposition in all-solid-state Li metal batteries is greatly influenced by the anode/electrolyte interface.Herein,a Mg-modified interface was constructed via the simple in-situ electrochemical reduction of Mg^(2+)from Mg(TFSI)_(2) in polyethylene oxide(PEO)and a Li bis(trifluoromethane)sulfoni mide(Li TFSI)formulae.As confirmed by cryogenic transmission electron microscopy,the anode/electrolyte interface exhibited hybrids consisting of crystalline Mg,Li_(2)O,and Li dots embedded in an amorphous polymer electrolyte.The crystalline Mg dots guided the uniform Li nucleation and growth,inducing a smoother anode/electrolyte interface compared with the pristine electrolyte.With 1 wt%Mg(TFSI)_(2) in the PEO-Li TFSI electrolyte,the Mg-modified electrolyte enabled the Li/Li symmetric cells with cycling performance of over 1700 and 1400 h at current densities of 0.1 and 0.2 m A cm^(-2),respectively.Moreover,the full LFP/Li cells using the novel Mg-modified electrolyte delivered a cycling lifespan of over 450 cycles with negligible capacity loss.
基金financial support from the National Key R&D Program of China (grant 2022YFB3807700)the National Natural Science Foundation of China (grants 52171225,52102314,52225208,51972285 and U21A20174)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang (grant 2020R01002)。
文摘All-solid-state lithium(Li)metal batteries(ASSLMBs)are considered one of the most promising secondary batteries due to their high theoretical capacity and high safety performance.However,low room-temperature ionic conductivity and poor interfacial stability are two key factors affecting the practical application of ASSLMBs,and our understanding of the mechanisms behind these key problems from microscopic perspective is still limited.In this review,the mechanisms and advanced characterization techniques of ASSLMBs are summarized to correlate the microstructures and properties.Firstly,we summarize the challenges faced by solid polymer electrolytes(SPEs)in ASSLMBs,such as the low roomtemperature ionic conductivity and the poor interfacial stability.Secondly,several typical improvement methods of polymer ASSLMBs are discussed,including composite SPEs,ultra-thin SPEs,SPEs surface modification and Li anode surface modification.Finally,we conclude the characterizations for correlating the microstructures and the properties of SPEs,with emphasis on the use of emerging advanced techniques(e.g.,cryo-transmission electron microscopy)for in-depth analyzing ASSLMBs.The influence of the microstructures on the properties is very important.Until now,it has been difficult for us to understand the microstructures of batteries.However,some recent studies have demonstrated that we have a better understanding of the microstructures of batteries.Then we suggest that in situ characterization,nondestructive characterization and sub-angstrom resolution are the key technologies to help us further understand the batteries'microstructures and promote the development of batteries.And potential investigations to understand the microstructures evolution and the batteries behaviors are also prospected to expect further reasonable theoretical guidance for the design of ASSLMBs with ideal performance.
基金financially supported by the National Natural Science Foundation of China (No.21506081,21506077)Jiangsu University Scientific Research Funding (15JDG048)+1 种基金Chinese Postdoctoral Foundation (2016M590420)Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘On account of the high theoretical capacity, high corrosion resistance, environmental benignity, abundant availability and low cost, the research on a-Fe_2O_3 has been gradually fastened on as promising anodes materials toward lithium-ion batteries(LIBs). A high-performance anode for LIBs based on α-Fe_2O_3 nanoplates have been selectively prepared. The α-Fe_2O_3 nanoplates can be synthesized with iron ionbased ionic liquid as iron source and template. The α-Fe_2O_3 nanoplates as the anode of LIBs can display high capacity of around1950 mAh g^(-1) at 0.5 A g^(-1) which have exceeded the theoretical capacity of α-Fe_2O_3. On account of unique nanoplate structures and gum arabic as binder, the α-Fe_2O_3 nanoplates also exhibit high rate capability and excellent cycling performance.
基金financial support by the National Key R&D Program of China(No.2022YFB2502000)National Natural Science Foundation of China(Nos.52225208,52002352,U21A20174 and 52071295)Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2020R01002)。
文摘In order to solve the problem of poor conductivity of traditional LiFePO_(4)cathode binders,we developed sodium alginate-Congo red copolymers(SA-CR)as water-soluble electrically conductive and mechanically robust composite binder.Unlike most other electrically conductive polymer binders,the procedure is straightforward and low-cost to prepare SA-CR binder.Various SA-CR copolymers were prepared with different degree of compounding of CR to investigate the effect of CR on the electrochemical and physical properties of the prepared electrodes.The copolymer whose composition was filled with a mixture of SA and CR at a 3:1 mass ratio showed the best cell performance,due to the well-balanced electrical conductivity and mechanical properties.It exhibited a specific capacity of 118.8 m Ah/g at the 100th cycle with 92.1%capacity retention,significantly better than the 108.5 m Ah/g of conventional acetylene black electrodes.CR as a conduction-promoting agent in water-soluble composite binder favors the formation of continuous and homogenous conducting bridges throughout the electrode and increases the compaction density of electrode by reducing the conducting agent content of acetylene black and thus the improvement of electrode performance is realized.
基金supported by the National Natural Science Foundation of China [NSFC, grant numbers U22A20113 and 52261135543]。
文摘Ni-rich layered oxides are promising cathodes for high-energy lithium-ion batteries,but the chemoelectro-mechanical deterioration of polycrystalline particles caused by intergranular microcracks hinders their applications.Herein,a perovskite LiTaO_(3) strengthening network along the grain boundaries is designed to enhance the mechanical and structural stability of polycrystalline LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) by suppressing the anisotropic volume variation and retard the internal strain.Notably,the perovskite-modified LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode material exhibits significantly improved cyclability and rate capacity.Such enhanced electrochemical behavior can be ascribed not merely to the compacted particle,where the LiTaO_(3) interface effectively inhibits electrolyte infiltration,but also to the structural stability in terms of inhibiting lattice oxygen release through the introduction of strong Ta-O bonds,thereby restraining interfacial side reactions and surface phase transitions.This work provides precise control over grain boundaries to suppress the inter-strain,taking care of the crystal structure and interface properties.
基金National Natural Science Foundation of China,Grant/Award Numbers:52002352,52071295。
文摘Sodium(Na)ion batteries(SIBs)promise low-cost energy storage systems but are still restricted by insufficient energy density.Introducing oxygen(O)redox into the design of the Na-storage cathode is presently considered an effective avenue to generate extra capacity in solving the energy density bottleneck.The succeeding issues are how to overcome the irreversible electrochemical behavior accompanied by O release.Meanwhile,the O redox chemistry and subsequent structural evolution remain ambiguous so far.Here,we deliberate on the O redox mechanism in Na-storage transition metal oxides.Challenges associated with the reaction irreversibility and structural collapse are summarized by virtue of the advanced characterization techniques.Beyond that,strategies that potentially enhance the electrochemical properties of O redox and future research perspectives on exploring useable O redox cathode materials are outlined.
基金supported by the National Key Research and Development Program of China(2022YFB3807700)the National Natural Science Foundation of China(52171225,52102314,52225208,51972285,U21A20174)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(2020R01002)
文摘Lithium-ion batteries(LIBs)have been in a dominant position in the new energy industry because of their excellent comprehensive performance.The performance of LIBs highly depends on the microstructures of the materials that constitute LIBs.Particularly,the relatively“weak”molecular interactions instead of the common-discussed strong chemical-bonding always affect the structures and the consequent properties of the components in LIBs.As a typical example,the hydrogen bonds,which widely exist inside LIBs,greatly improved the mechanical strength,lithium ion(Li^(+))transport rate and the intrinsic stabilities towards boosting performance of LIBs.This review starts from the interaction force between molecules,and especially summarizes the correlation between the formation of hydrogen bonds and the properties of the typical components in LIBs(cathode,anode,electrolyte,separator).In addition,how the formation of hydrogen bonds affects the performance of LIBs components is discussed.Finally,the strategies of combining hydrogen bonds with LIBs components in the future are prospected,which provide guidance for the rational design of high-performance LIBs.
