Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operati...Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.展开更多
In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with ...In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.展开更多
文摘Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.
文摘In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.