LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA)secondary particles with high tap density have a great potential for high volumetric energy density lithium(Li)-ion power bat-tery.However,the ionic conductivity mechanism of NCA ...LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA)secondary particles with high tap density have a great potential for high volumetric energy density lithium(Li)-ion power bat-tery.However,the ionic conductivity mechanism of NCA with compact structure is still a suspense,especially the function of grain boundaries.Herein,we sys-tematically investigate the Li-ion transport behavior in both the primitive NCA(PNCA)secondary sphere densely grown by single-crystal primary grains and ball-milled NCA(MNCA)nanosized particle to reveal the role of grain bound-aries for Li-ion transport.The PNCA and MNCA have comparable Li-ion dif-fusion coefficients and rate performance.Moreover,the graphene nanosheet conductive additive only mildly affects the Li-ion diffusion in PNCA cathode,while which severely blocks the Li-ion transport in MNCA cathode.Through high-resolution transmission electron microscopy and electron energy loss spec-troscopy,we clearly observe Li-ion depletion at lower state of charge(SOC)and Li-ion aggregation at high SOC along the grain boundaries of PNCA secondary particles during high-rate lithiation process.The grain boundaries can construct an interconnected Li-ion transport network for highly efficient Li-ion transport,which contributes to excellent high-rate performance of compact PNCA sec-ondary particles.These findings present new strategy and deep insight in design-ing compact materials with excellent high-rate performance.展开更多
The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of SOFCs.This has stimulated a substantial materials research effort in developi...The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of SOFCs.This has stimulated a substantial materials research effort in developing high oxide-ion conductivity in the electrolyte layer of SOFCs.In this context,for the first time,a dielectric material,CaCu_(3)Ti_(4)O_(12)(CCTO)is designed for LT-SOFCs electrolyte application in this study.Both individual CCTO and its heterostructure materials with a p-type Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ)(NCAL)semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550℃.The single cell with the individual CCTO electrolyte exhibits a power output of approximately 263 mW cm^(-2) and an open-circuit voltage(OCV)of 0.95 V at 550℃,while the cell with the CCTO–NCAL heterostructure electrolyte capably delivers an improved power output of approximately 605 mW cm^(-2) along with a higher OCV over 1.0 V,which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell performance rather than inducing any potential short-circuiting risk.It is found that these promising outcomes are due to the interplay of the dielectric material,its structure,and overall properties that led to improve electrochemical mechanism in CCTO–NCAL.Furthermore,density functional theory calculations provide the detailed information about the electronic and structural properties of the CCTO and NCAL and their heterostructure CCTO–NCAL.Our study thus provides a new approach for developing new advanced electrolytes for LT-SOFCs.展开更多
LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA) is a promising cathode for sulfide-based solid-state lithium batteries(ASSLBs)profiting from its high specific capacity and voltage plateau, which yielding high energy density. H...LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA) is a promising cathode for sulfide-based solid-state lithium batteries(ASSLBs)profiting from its high specific capacity and voltage plateau, which yielding high energy density. However, the inferior interfacial stability between the bare NCA and sulfides limits its electrochemical performance. Hereien, the dual-electrolyte layer is proposed to mitigate this effect and enhance the battery performances of NCA-based ASSLIBs. The Li_(3)InCl_6 wih high conductivity and excellent electrochemcial stability act both as an ion additives to promote Li-ion diffusion across the interface in the cathode and as a buffer layer between the cathode layer and the solid electrolyte layer to avoid side reactions and improve the interface stability. The corresponding battery exhibits high discharge capacities and superior cyclabilities at both room and elevated temperatures. It exhibits discharge performance of 237.04 and216.07 m Ah/g at 0.1 and 0.5 C, respectively, when cycled at 60 ℃, and sustains 95.9% of the capacity after100 cycles at 0.5 C. The work demonstrates a simple strategy to ensure the superior performances of NCA in sulfide-based ASSLBs.展开更多
基金National Natural Science Founda-tion of China,Grant/Award Number:U2001220Local Innovative Research Teams Project of Guangdong Pearl River Talents Program,Grant/Award Number:2017BT01N111+2 种基金Shenzhen Technical Plan Project,Grant/Award Numbers:JCYJ20180508152135822,JCYJ20180508152210821,JCYJ20170412170706047Shenzhen graphene manufacturing innova-tion center,Grant/Award Number:201901161513Shenzhen All-Solid-State Lithium Battery Electrolyte Engineering Research Center,Grant/Award Number:XMHT20200203006。
文摘LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA)secondary particles with high tap density have a great potential for high volumetric energy density lithium(Li)-ion power bat-tery.However,the ionic conductivity mechanism of NCA with compact structure is still a suspense,especially the function of grain boundaries.Herein,we sys-tematically investigate the Li-ion transport behavior in both the primitive NCA(PNCA)secondary sphere densely grown by single-crystal primary grains and ball-milled NCA(MNCA)nanosized particle to reveal the role of grain bound-aries for Li-ion transport.The PNCA and MNCA have comparable Li-ion dif-fusion coefficients and rate performance.Moreover,the graphene nanosheet conductive additive only mildly affects the Li-ion diffusion in PNCA cathode,while which severely blocks the Li-ion transport in MNCA cathode.Through high-resolution transmission electron microscopy and electron energy loss spec-troscopy,we clearly observe Li-ion depletion at lower state of charge(SOC)and Li-ion aggregation at high SOC along the grain boundaries of PNCA secondary particles during high-rate lithiation process.The grain boundaries can construct an interconnected Li-ion transport network for highly efficient Li-ion transport,which contributes to excellent high-rate performance of compact PNCA sec-ondary particles.These findings present new strategy and deep insight in design-ing compact materials with excellent high-rate performance.
基金National Natural Science Foundation of China(NSFC)supported this work under Grant No.32250410309,11674086,51736006,and 51772080funding from Science and Technology Department of Jiangsu Province under Grant No.BE2022029Shenzhen University under Grant No.86902/000248 also supported part of this work.
文摘The development of low-temperature solid oxide fuel cells(LT-SOFCs)is of significant importance for realizing the widespread application of SOFCs.This has stimulated a substantial materials research effort in developing high oxide-ion conductivity in the electrolyte layer of SOFCs.In this context,for the first time,a dielectric material,CaCu_(3)Ti_(4)O_(12)(CCTO)is designed for LT-SOFCs electrolyte application in this study.Both individual CCTO and its heterostructure materials with a p-type Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2−δ)(NCAL)semiconductor are evaluated as alternative electrolytes in LT-SOFC at 450–550℃.The single cell with the individual CCTO electrolyte exhibits a power output of approximately 263 mW cm^(-2) and an open-circuit voltage(OCV)of 0.95 V at 550℃,while the cell with the CCTO–NCAL heterostructure electrolyte capably delivers an improved power output of approximately 605 mW cm^(-2) along with a higher OCV over 1.0 V,which indicates the introduction of high hole-conducting NCAL into the CCTO could enhance the cell performance rather than inducing any potential short-circuiting risk.It is found that these promising outcomes are due to the interplay of the dielectric material,its structure,and overall properties that led to improve electrochemical mechanism in CCTO–NCAL.Furthermore,density functional theory calculations provide the detailed information about the electronic and structural properties of the CCTO and NCAL and their heterostructure CCTO–NCAL.Our study thus provides a new approach for developing new advanced electrolytes for LT-SOFCs.
基金supported by the National Key Research and Development Program (No.2021YFB2500200)the National Natural Science Foundation of China (No.52177214)supported by China Fujian Energy Devices Science and Technology Innovation Laboratory Open Fund (No.21C-OP202211)。
文摘LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)(NCA) is a promising cathode for sulfide-based solid-state lithium batteries(ASSLBs)profiting from its high specific capacity and voltage plateau, which yielding high energy density. However, the inferior interfacial stability between the bare NCA and sulfides limits its electrochemical performance. Hereien, the dual-electrolyte layer is proposed to mitigate this effect and enhance the battery performances of NCA-based ASSLIBs. The Li_(3)InCl_6 wih high conductivity and excellent electrochemcial stability act both as an ion additives to promote Li-ion diffusion across the interface in the cathode and as a buffer layer between the cathode layer and the solid electrolyte layer to avoid side reactions and improve the interface stability. The corresponding battery exhibits high discharge capacities and superior cyclabilities at both room and elevated temperatures. It exhibits discharge performance of 237.04 and216.07 m Ah/g at 0.1 and 0.5 C, respectively, when cycled at 60 ℃, and sustains 95.9% of the capacity after100 cycles at 0.5 C. The work demonstrates a simple strategy to ensure the superior performances of NCA in sulfide-based ASSLBs.
