Ordered layered honeycomb structures are crucial for the unique redox mechanism in Co-free Li-rich oxide materials(LMNO).However,oxygen release and irreversible cation migration originating from this distinctive struc...Ordered layered honeycomb structures are crucial for the unique redox mechanism in Co-free Li-rich oxide materials(LMNO).However,oxygen release and irreversible cation migration originating from this distinctive structure during cycling have hindered the further commercialization of LMNO.Herein,we report a strategy to modulate the nanoscale atomic arrangement and electronic band structures by deliberately introducing an integrated short-range disorder in the Li-rich structure with Ce/F dual-doping(denoted as LMNO-CFSD).This work explicitly reveals the induction of this disordered structure and comprehensively investigates its effects on the lattice stability.As a result,the LMNO-CFSD cathode exhibits a high energy density of 934.8 Wh kg_(cathode)^(-1),and achieves a remarkable lifespan of 800 cycles with 70.1%capacity retention at 1 C in LMNO-CFSD||graphite full cells.Spectroscopic studies corroborated by first-principles calculations reveal that this integrated short-range disorder with dual-doping effectively modulates the formation energy of oxygen vacancies.It also tailors the crystal and anionic band structure in the Li-rich phase,fundamentally mitigating detrimental oxygen release and transition metal migration during Li^(+)(de)intercalation.Our findings illuminate the crucial role of correlated disorder in enhancing the electrochemical properties of Li-rich layered oxides,thereby offering new design principles for high-performance cathode materials in next-generation lithium batteries.展开更多
Polymer electrolytes featuring flexibility,processability,and compatibility with large-scale roll-to-roll fabrication processes have emerged as promising candidates for solid-state lithium metal batteries.Herein,we ha...Polymer electrolytes featuring flexibility,processability,and compatibility with large-scale roll-to-roll fabrication processes have emerged as promising candidates for solid-state lithium metal batteries.Herein,we have designed and synthesized an all-in-one free-standing acrylate-grafted cellulose separator polymer electrolyte(ACSPE)through the copolymerization of acrylate-grafted cellulose separator(ACS).This synthetic strategy leverages the abundant hydroxyl groups in the cellulose separator,which are substituted with acryloyl chloride to form an acrylate-grafted separator.The resulting ACSPE exhibits a high ionic conductivity of 1.78×10^(-3) S·cm^(-1) at room temperature,improved oxidation stability(5.57 V),and enhanced mechanical strength(10.0 MPa),indicating its high compatibility with high-voltage cathode,Li metal anode,and scalable roll-to-roll production processes.Li|ACSPE|LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cells exhibit a long stable cycle life of 1000 cycles at 0.5 C/1 C with capacity retention of 75.6%,achieving stable performance across a wide temperature range from 0 to 60℃.Furthermore,when paired with a 50μm thin Li foil,full cells using NCM811 cathode with a mass loading of 6 mg·cm^(-2) exhibit a high discharge capacity of 191.0 mAh·g^(-1) at 0.1 C and maintain excellent cycling stability with a retention rate of 93.3% after 100 cycles.This study provides valuable insights into the chemical modification and design strategies for improving the processability and performance of polymer-based solid-state batteries.展开更多
基金supported by the National Natural Science Foundation of China(NSFC,52090034)the National Key R&D Program of China(2020YFA0711500)。
文摘Ordered layered honeycomb structures are crucial for the unique redox mechanism in Co-free Li-rich oxide materials(LMNO).However,oxygen release and irreversible cation migration originating from this distinctive structure during cycling have hindered the further commercialization of LMNO.Herein,we report a strategy to modulate the nanoscale atomic arrangement and electronic band structures by deliberately introducing an integrated short-range disorder in the Li-rich structure with Ce/F dual-doping(denoted as LMNO-CFSD).This work explicitly reveals the induction of this disordered structure and comprehensively investigates its effects on the lattice stability.As a result,the LMNO-CFSD cathode exhibits a high energy density of 934.8 Wh kg_(cathode)^(-1),and achieves a remarkable lifespan of 800 cycles with 70.1%capacity retention at 1 C in LMNO-CFSD||graphite full cells.Spectroscopic studies corroborated by first-principles calculations reveal that this integrated short-range disorder with dual-doping effectively modulates the formation energy of oxygen vacancies.It also tailors the crystal and anionic band structure in the Li-rich phase,fundamentally mitigating detrimental oxygen release and transition metal migration during Li^(+)(de)intercalation.Our findings illuminate the crucial role of correlated disorder in enhancing the electrochemical properties of Li-rich layered oxides,thereby offering new design principles for high-performance cathode materials in next-generation lithium batteries.
基金the National Natural Science Foundation of China(No.52090034)the National Key R&D Program of China(No.2020YFA0711500)the Beijing-Tianjin-Hebei Basic Research Cooperation Project(No.B24JCZXJC00360).
文摘Polymer electrolytes featuring flexibility,processability,and compatibility with large-scale roll-to-roll fabrication processes have emerged as promising candidates for solid-state lithium metal batteries.Herein,we have designed and synthesized an all-in-one free-standing acrylate-grafted cellulose separator polymer electrolyte(ACSPE)through the copolymerization of acrylate-grafted cellulose separator(ACS).This synthetic strategy leverages the abundant hydroxyl groups in the cellulose separator,which are substituted with acryloyl chloride to form an acrylate-grafted separator.The resulting ACSPE exhibits a high ionic conductivity of 1.78×10^(-3) S·cm^(-1) at room temperature,improved oxidation stability(5.57 V),and enhanced mechanical strength(10.0 MPa),indicating its high compatibility with high-voltage cathode,Li metal anode,and scalable roll-to-roll production processes.Li|ACSPE|LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cells exhibit a long stable cycle life of 1000 cycles at 0.5 C/1 C with capacity retention of 75.6%,achieving stable performance across a wide temperature range from 0 to 60℃.Furthermore,when paired with a 50μm thin Li foil,full cells using NCM811 cathode with a mass loading of 6 mg·cm^(-2) exhibit a high discharge capacity of 191.0 mAh·g^(-1) at 0.1 C and maintain excellent cycling stability with a retention rate of 93.3% after 100 cycles.This study provides valuable insights into the chemical modification and design strategies for improving the processability and performance of polymer-based solid-state batteries.
