Lithium sulfur battery （LSB） offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of t...Lithium sulfur battery （LSB） offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the dissolution of reaction intermediates, lithium polysulfides, into the electrolyte. To solve this limitation, there are many studies using graphene-based materials due to their excellent mechanical strength and high conductivity. Compared with graphene, graphene oxide （GO） contains various oxygen functional groups, which enhance the reaction with lithium polysulfides. Here, we investigated the positive effect of using GO mixed with carbon black on the performance of cathode in LSB. We have observed a smaller drop of capacity in GO mixed sulfur cathode. We further demonstrate that the mechanistic origin of reversibility improvement, as confirmed through CV and Raman spectra, can be explained by the stabilization of sulfur in lithium polysulfide intermediates by oxygen functional groups of GO to prevent dissolution. Our findings suggest that the use of graphene oxide-based cathode is a promising route to significantly improve the reversibility of current LSB.展开更多
CONSPECTUS:Sulfur,being lightweight,cost-effective,and offering a remarkably high lithium-ion storage capacity,has positioned lithium−sulfur(Li−S)batteries as promising candidates for applications that demand high ene...CONSPECTUS:Sulfur,being lightweight,cost-effective,and offering a remarkably high lithium-ion storage capacity,has positioned lithium−sulfur(Li−S)batteries as promising candidates for applications that demand high energy density.These range from electric vehicles(EVs)to urban air mobility(UAM)systems.Despite this potential,Li−S batteries still face significant performance challenges,limiting their practical application.Chief among these challenges are the limited lifespan and low charge−discharge efficiency,predominantly caused by the dissolution of lithium polysulfide intermediate products formed during battery cycling in ether-based electrolytes.Moreover,sulfur and lithium sulfide,which constitute the active material in the cathode,are intrinsically insulating,complicating efforts to increase the active material content in the cathode and fabricate thick cathodes with high conductivity.These issues have long stood in the way of Li−S batteries achieving commercial viability.Overcoming these obstacles requires a multifaceted approach that focuses on modifications at the level of the cathode materials such as the active material,conductive agents,binders,and additives.This Account delves into these key challenges and presents a comprehensive overview of research strategies aimed at enhancing the performance of Li−S batteries with a particular focus on the sulfur cathode.First,the Account addresses practical challenges in Li−S batteries,such as the complex composition of the cathode,the low sulfur utilization efficiency,suboptimal electrolyte-to-sulfur ratios,and nonuniform sulfur conversion reactions.Strategies to overcome these barriers include the design of advanced cathode architectures that promote high sulfur utilization and an improved energy density.Modifications to the components of the cathode and the adjoining materials,such as the incorporation of conductive additives,help mitigate the insulating nature of sulfur.Additionally,the Account places particular emphasis on the innovative use of pelletizing techniques in sulfur cathode fabrication,which has demonstrated notable improvements in the cathode performance.One of the Account’s highlights is the discussion of lowtemperature operation strategies for Li−S batteries,which is a critical area for real-world application,especially in aerospace and cold-environment operations.There are significant performance differences when transitioning from lab-scale coin cells to larger pouch cells,underscoring the importance of considering cell geometries and their impact on the scalability and performance.Finally,the Account explores the development of all-solid-state Li−S batteries,a promising approach that could fundamentally address the issue of lithium polysulfide dissolution by eliminating the use of liquid electrolytes altogether.The inherent drawbacks of Li−S batteries,such as the insulating nature of sulfur and the challenges of high sulfur loading,can be strategically addressed to pave the way for their commercialization.In doing so,Li−S batteries offer a clear pathway beyond the limitations of conventional lithium-ion batteries,making them a highly attractive option for applications requiring high gravimetric and volumetric energy densities.展开更多
基金supported by the Core Technology Development Program for Next-Generation Energy Storage of the Research Institute for Solar and Sustainable Energies (RISE) at GISTthe DOST UPD ERDT Faculty Development Program
文摘Lithium sulfur battery （LSB） offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the dissolution of reaction intermediates, lithium polysulfides, into the electrolyte. To solve this limitation, there are many studies using graphene-based materials due to their excellent mechanical strength and high conductivity. Compared with graphene, graphene oxide （GO） contains various oxygen functional groups, which enhance the reaction with lithium polysulfides. Here, we investigated the positive effect of using GO mixed with carbon black on the performance of cathode in LSB. We have observed a smaller drop of capacity in GO mixed sulfur cathode. We further demonstrate that the mechanistic origin of reversibility improvement, as confirmed through CV and Raman spectra, can be explained by the stabilization of sulfur in lithium polysulfide intermediates by oxygen functional groups of GO to prevent dissolution. Our findings suggest that the use of graphene oxide-based cathode is a promising route to significantly improve the reversibility of current LSB.
基金supported by the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.GTL24011-000)supported by Nano·Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(RS-2024-00455177).
文摘CONSPECTUS:Sulfur,being lightweight,cost-effective,and offering a remarkably high lithium-ion storage capacity,has positioned lithium−sulfur(Li−S)batteries as promising candidates for applications that demand high energy density.These range from electric vehicles(EVs)to urban air mobility(UAM)systems.Despite this potential,Li−S batteries still face significant performance challenges,limiting their practical application.Chief among these challenges are the limited lifespan and low charge−discharge efficiency,predominantly caused by the dissolution of lithium polysulfide intermediate products formed during battery cycling in ether-based electrolytes.Moreover,sulfur and lithium sulfide,which constitute the active material in the cathode,are intrinsically insulating,complicating efforts to increase the active material content in the cathode and fabricate thick cathodes with high conductivity.These issues have long stood in the way of Li−S batteries achieving commercial viability.Overcoming these obstacles requires a multifaceted approach that focuses on modifications at the level of the cathode materials such as the active material,conductive agents,binders,and additives.This Account delves into these key challenges and presents a comprehensive overview of research strategies aimed at enhancing the performance of Li−S batteries with a particular focus on the sulfur cathode.First,the Account addresses practical challenges in Li−S batteries,such as the complex composition of the cathode,the low sulfur utilization efficiency,suboptimal electrolyte-to-sulfur ratios,and nonuniform sulfur conversion reactions.Strategies to overcome these barriers include the design of advanced cathode architectures that promote high sulfur utilization and an improved energy density.Modifications to the components of the cathode and the adjoining materials,such as the incorporation of conductive additives,help mitigate the insulating nature of sulfur.Additionally,the Account places particular emphasis on the innovative use of pelletizing techniques in sulfur cathode fabrication,which has demonstrated notable improvements in the cathode performance.One of the Account’s highlights is the discussion of lowtemperature operation strategies for Li−S batteries,which is a critical area for real-world application,especially in aerospace and cold-environment operations.There are significant performance differences when transitioning from lab-scale coin cells to larger pouch cells,underscoring the importance of considering cell geometries and their impact on the scalability and performance.Finally,the Account explores the development of all-solid-state Li−S batteries,a promising approach that could fundamentally address the issue of lithium polysulfide dissolution by eliminating the use of liquid electrolytes altogether.The inherent drawbacks of Li−S batteries,such as the insulating nature of sulfur and the challenges of high sulfur loading,can be strategically addressed to pave the way for their commercialization.In doing so,Li−S batteries offer a clear pathway beyond the limitations of conventional lithium-ion batteries,making them a highly attractive option for applications requiring high gravimetric and volumetric energy densities.
