| Autor: |
Burns DA; Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States., Baumann AE; Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States., Bennett KJ; Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States., Díaz JC; Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States., Thoi VS; Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States.; Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States. |
| Abstrakt: |
Demands for energy storage and delivery continue to rise worldwide, making it imperative that reliable performance is achievable in diverse climates. Lithium-sulfur (Li-S) batteries offer a promising alternative to lithium-ion batteries owing to their substantially higher specific capacity and energy density. However, improvements to Li-S systems are still needed in low-temperature environments where polysulfide clustering and solubility limitations prohibit complete charge/discharge cycles. We address these issues by introducing thiophosphate-functionalized metal-organic frameworks (MOFs), capable of tethering polysulfides, into the cathode architecture. Compared to cells with the parent MOFs, cells containing the functionalized MOFs exhibit greater capacity delivery and decreased polarization for a range of temperatures down to -10 °C. We conduct thorough electrochemical analyses to ascertain the origins of performance differences and report an altered Li-S redox mechanism enabled by the thiophosphate moiety. This investigation is the first low-temperature Li-S study using MOF additives and represents a promising direction in enabling energy storage in extreme environments. |
