The repeated volume variation of lithium(Li)metal anode(LMA)upon Li^(+) plating/stripping,the volatile interface between Li and the electrolyte,and the incessant growth of Li dendrites on Li metal surface have severel...The repeated volume variation of lithium(Li)metal anode(LMA)upon Li^(+) plating/stripping,the volatile interface between Li and the electrolyte,and the incessant growth of Li dendrites on Li metal surface have severely hindered the practical application of Li in constructing high energy-density Li metal batteries(LMBs).Herein,a novel Li host(3D ZnO/CNTs/Cu)featuring ordered microchannels and lithiophilic ZnO species on the inner walls of the microchannels is introduced,which induces the uniform Li^(+) deposition into the microchannels and finally suppresses the formation of Li dendrites.The stable structure of the fabricated 3D Li host can adapt to volume variations upon Li^(+) plating/stripping,thereby enhancing electrochemical performances.Symmetric cells with the 3D ZnO/CNTs/Cu@Li anode exhibited long cycle stability at areal current densities of 0.5 and 2 mA cm^(-2);Full cells maintained a reversible discharge capacity of 105 mAh g^(-1) after 400 cycles at 1C with a capacity retention of 70%.Meanwhile,ex-situ SEM observations proved that the 3D ZnO/CNTs/Cu@Li anode can keep the structural integrity during charging/discharging(or plating/stripping).This work suggested that lithiophilic nanochannels in the Li host can significantly improve the electrochemical performance and safety of LMBs.展开更多
Lithium/sulfur （Li/S） cells have great potential to become mainstream secondary batteries due to their ultra-high theoretical specific energy. The major challenge for Li/S cells is the unstable cycling performance c...Lithium/sulfur （Li/S） cells have great potential to become mainstream secondary batteries due to their ultra-high theoretical specific energy. The major challenge for Li/S cells is the unstable cycling performance caused by the sulfur＇s insulating nature and the high-solubility of the intermediate polysulfide products. Several years of efforts to develop various fancy carbon nanostructures, trying to physically encapsulate the polysulfides, did not yet push the cell＇s cycle life long enough to compete with current Li ion cells. The focus of this review is on the recent progress in chemical bonding strategy for trapping polysulfides through employing functional groups and additives in carbon matrix. Research results on understanding the working mechanism of chemical interaction between polysulfides and functional groups （e.g. 0-, B-, N- and S-） in carbon matrix, metal-based additives, or polymer additives during charge/discharge are discussed.展开更多
基金supported by the Science Foundation of Zhejiang Sci-Tech University(18062299-Y)。
文摘The repeated volume variation of lithium(Li)metal anode(LMA)upon Li^(+) plating/stripping,the volatile interface between Li and the electrolyte,and the incessant growth of Li dendrites on Li metal surface have severely hindered the practical application of Li in constructing high energy-density Li metal batteries(LMBs).Herein,a novel Li host(3D ZnO/CNTs/Cu)featuring ordered microchannels and lithiophilic ZnO species on the inner walls of the microchannels is introduced,which induces the uniform Li^(+) deposition into the microchannels and finally suppresses the formation of Li dendrites.The stable structure of the fabricated 3D Li host can adapt to volume variations upon Li^(+) plating/stripping,thereby enhancing electrochemical performances.Symmetric cells with the 3D ZnO/CNTs/Cu@Li anode exhibited long cycle stability at areal current densities of 0.5 and 2 mA cm^(-2);Full cells maintained a reversible discharge capacity of 105 mAh g^(-1) after 400 cycles at 1C with a capacity retention of 70%.Meanwhile,ex-situ SEM observations proved that the 3D ZnO/CNTs/Cu@Li anode can keep the structural integrity during charging/discharging(or plating/stripping).This work suggested that lithiophilic nanochannels in the Li host can significantly improve the electrochemical performance and safety of LMBs.
文摘Lithium/sulfur （Li/S） cells have great potential to become mainstream secondary batteries due to their ultra-high theoretical specific energy. The major challenge for Li/S cells is the unstable cycling performance caused by the sulfur＇s insulating nature and the high-solubility of the intermediate polysulfide products. Several years of efforts to develop various fancy carbon nanostructures, trying to physically encapsulate the polysulfides, did not yet push the cell＇s cycle life long enough to compete with current Li ion cells. The focus of this review is on the recent progress in chemical bonding strategy for trapping polysulfides through employing functional groups and additives in carbon matrix. Research results on understanding the working mechanism of chemical interaction between polysulfides and functional groups （e.g. 0-, B-, N- and S-） in carbon matrix, metal-based additives, or polymer additives during charge/discharge are discussed.
