Solid electrolyte interphase(SEI)plays a critical role in stabilizing zinc batteries,yet insufficient attention has been given to its in-situ growth kinetics and the post-stripping morphology of zinc anodes,both affec...Solid electrolyte interphase(SEI)plays a critical role in stabilizing zinc batteries,yet insufficient attention has been given to its in-situ growth kinetics and the post-stripping morphology of zinc anodes,both affecting the SEI-forming quality.Herein,we showcase a synergistic effect between uniform Zn stripping and rapid SEI formation through introducing tetramethylurea(TMU)into Zn(BF_(4))_(2)-based electrolytes.TMU participates in the Zn^(2+)solvation structure and reshapes the electrolyte hydrogen-bond network,enabling a water-poor electric double layer that mitigates the corrosion-induced stripping inhomogeneity.Subsequently,a multi-component and inorganic-rich SEI with high uniformity is rapidly deposited during the plating process.This SEI with abundant zincophilic sites activates instantaneous nucleation and hence guides dense and uniform Zn deposition.With enhanced Zn stripping/plating symmetry,the long-term effectiveness of SEI is guaranteed,contributing to the high reversibility over 3200 h at 1 mA cm^(-2)/2 mAh cm^(-2).Impressively,the Zn//NaV_(3)O_(8)full cell(4.43 mAh cm^(-2))can be steadily cycled at 0.1 A g^(-1)under an intermittent-rest protocol.The stable operation of an Ah-level pouch cell over 100 cycles further demonstrates the scalability of this strategy and highlights the significance of achieving high stripping/plating symmetry and a long-term effective SEI toward practical zinc batteries.展开更多
Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevit...Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevitable,and even worse,due to a trend of big-size cell design,typically such as 4680 and blade cells,which accelerated a battery failure during repeat lithiation and delithiation of cathodes.Inspire by that,two big-size pouch cells with big sizes,herein,are selected to reveal the ion-diffusion dependency of the cathodes at different locations.Interestingly,we find that the LiCoO_(2) pouch cell exhibits ~5 A h loss after 120 charge-discharge cycles,but a 15 A h loss is verified in a LiNixMnyCO_(1-x)-yO_(2)(NCM) cell.Synchrotron-based imaging analysis indicates that higher ion-diffusion rates in the LiCoO_(2)than that in the LiNixMnyCO_(1-x)-yO_(2)is the determined factor for the anisotropic cathode fading,which is responsible for a severe mechanical issue of particle damage,such as cracks and even pulverization,in the cathode materials.Meanwhile,we verify the different locations at the near-tab and bottom of the electrode make it worse due to the ion-diffusion kinetics and temperature,inducing a spatially uneven electrochemistry in the big-size pouch cell.The findings give an in-depth insight into pouch cell failure and make a guideline for high-energy cell design and development.展开更多
基金supported by the National Natural Science Foundation of China(52372252)the Science and Technology Innovation Program of Hunan Province(2024RC1022)+1 种基金the Hunan Provincial Natural Science Foundation of China(2025JJ60356)the Changsha Municipal Natural Science Foundation(kq2502024).
文摘Solid electrolyte interphase(SEI)plays a critical role in stabilizing zinc batteries,yet insufficient attention has been given to its in-situ growth kinetics and the post-stripping morphology of zinc anodes,both affecting the SEI-forming quality.Herein,we showcase a synergistic effect between uniform Zn stripping and rapid SEI formation through introducing tetramethylurea(TMU)into Zn(BF_(4))_(2)-based electrolytes.TMU participates in the Zn^(2+)solvation structure and reshapes the electrolyte hydrogen-bond network,enabling a water-poor electric double layer that mitigates the corrosion-induced stripping inhomogeneity.Subsequently,a multi-component and inorganic-rich SEI with high uniformity is rapidly deposited during the plating process.This SEI with abundant zincophilic sites activates instantaneous nucleation and hence guides dense and uniform Zn deposition.With enhanced Zn stripping/plating symmetry,the long-term effectiveness of SEI is guaranteed,contributing to the high reversibility over 3200 h at 1 mA cm^(-2)/2 mAh cm^(-2).Impressively,the Zn//NaV_(3)O_(8)full cell(4.43 mAh cm^(-2))can be steadily cycled at 0.1 A g^(-1)under an intermittent-rest protocol.The stable operation of an Ah-level pouch cell over 100 cycles further demonstrates the scalability of this strategy and highlights the significance of achieving high stripping/plating symmetry and a long-term effective SEI toward practical zinc batteries.
基金supported by the Natural Science Foundation of Heilongjiang Province (LH2021E031)National Key Research and Development Program of China (2021YFB2011200)funds from Chongqing Research Institute of HIT。
文摘Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevitable,and even worse,due to a trend of big-size cell design,typically such as 4680 and blade cells,which accelerated a battery failure during repeat lithiation and delithiation of cathodes.Inspire by that,two big-size pouch cells with big sizes,herein,are selected to reveal the ion-diffusion dependency of the cathodes at different locations.Interestingly,we find that the LiCoO_(2) pouch cell exhibits ~5 A h loss after 120 charge-discharge cycles,but a 15 A h loss is verified in a LiNixMnyCO_(1-x)-yO_(2)(NCM) cell.Synchrotron-based imaging analysis indicates that higher ion-diffusion rates in the LiCoO_(2)than that in the LiNixMnyCO_(1-x)-yO_(2)is the determined factor for the anisotropic cathode fading,which is responsible for a severe mechanical issue of particle damage,such as cracks and even pulverization,in the cathode materials.Meanwhile,we verify the different locations at the near-tab and bottom of the electrode make it worse due to the ion-diffusion kinetics and temperature,inducing a spatially uneven electrochemistry in the big-size pouch cell.The findings give an in-depth insight into pouch cell failure and make a guideline for high-energy cell design and development.
