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DOE OSTI · 1874098

Synergistic Effect of High Sulfur Loading Layered Cathode, Ceramic Separator and Gel Electrolyte

Zamani, Somayeh·Yi, Caspar·Gao, Xiaosi·Joo, Yong Lak (ORCID:0000000246461625)
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Abstract

Lithium sulfur (Li-S) batteries are promising candidates for next-generation energy storage devices as they are capable of providing higher energy density and lower cost in comparison to the state of the art Li-ion batteries. To gain these characteristics, there are challenges such as polysulfide crossover, large volume changes during cycling, and deposition of insulating lithium sulfide that need to be alleviated. A popular approach to address these issues is to control the structure and properties of the carbon cathode in order to influence the transport of polysulfides, surface area for reaction, and lithium sulfide deposition. Ceramic separators on the other hand can drastically affect ion diffusion and overall battery performance. Safety concerns regarding the flammable liquid electrolyte can be reduced by deploying gel electrolyte. Towards this direction, we developed a layer-on-layer cathode structure with sulfur-impregnated activated carbon alternating with graphene layer, which was fabricated by Air-assisted electrospray. A much higher sulfur loading compared to slurry cast cathodes can be provided in this method. Combining the new cathode with gel electrolyte can offer higher safety of the battery and capacity retention. Ceramic separator would compensate the reduced ion conductivity of the gel electrolyte and the combination of these variables will be very promising in improvement of battery performance and safety.

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25 ENERGY STORAGEGel ElectrolyteHighly Loaded CathodeHybrid SeparatorLi-Sulfur Battery

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Zamani, Somayeh, Yi, Caspar, Gao, Xiaosi, Joo, Yong Lak (ORCID:0000000246461625). 2020-11-20. Synergistic Effect of High Sulfur Loading Layered Cathode, Ceramic Separator and Gel Electrolyte. https://doi.org/10.2172/1874098

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