Balancing Electrolyte Donicity and Cathode Adsorption Capacity for High‐Performance LiS Batteries. Issue 23 (9th May 2022)

• Record Type: Journal Article
• Authors: Kim, Kiwon; Kim, Taeyoung; Moon, Jun Hyuk
• Is Part Of: Small. Volume 18:Issue 23(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-09
• Subjects: density functional theory calculations -- high donicity electorolytes -- lithium polysulfide adsorption -- lithium sulfide growth -- lithium sulfur batteries; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202201416
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: LiS batteries with high theoretical capacity are attracting attention as next‐generation energy storage systems. Much effort has been devoted to the introduction of cathode materials with strong adsorption to sulfide species, but it is presented that this selection should be refined in the application of high donicity electrolytes. The oxides with different adsorption capacities are explored while controlling the electrolyte donicity, confirming the trade‐off effect between the donicity and the adsorption capacity for sulfur conversion. Specifically, a cathode substrate containing oxide nanoparticles of MgO, NiO, Fe2 O3, Co3 O4, and V2 O5 is prepared with spectra in adsorption capacity as well as low and high donicity electrolytes by controlling the concentration of LiNO3 salt. Strong adsorbent oxides such as Co3 O4 and V2 O5 cause competitive adsorption of electrolyte salts in high donicity electrolytes, resulting in poor cell performance. High cell performance is achieved on weakly adsorbing oxides of MgO or NiO with high donicity electrolytes; the MgO‐containing cathode cell delivers a high discharge capacity of 1394 mAh g −1 at 0.2 C. It is believed that understanding the interactions between electrolytes and adsorbent substrates will be the cornerstone of high‐performance LiS batteries. Abstract : Oxides with different lithium polysulfide adsorption capacities are explored while controlling the electrolyte donicity to confirm their interaction. Strong adsorbing oxides such as Co3 O4 or V2 O5 cause competitive adsorption of electrolyte salts in high‐donicity electrolytes, which degrades cell performance. Weakly adsorbing oxides such as MgO or NiO with high donicity electrolytes lead to high cell performance.