Breaking the Mold: an Unusual Choice of Material Yields Incredibly Long-lasting Batteries
upstart writes in with an IRC submission:
Breaking the mold: An unusual choice of material yields incredibly long-lasting batteries:
The tremendous increase in the use of mobile technology, wearable electronics, and a wide range of portable devices in general over the past few decades, has driven scientists worldwide to seek out the next breakthrough in rechargeable batteries. Lithium-sulfur batteries (LSBs)-composed of a sulfur-based cathode and lithium anode submerged in a liquid electrolyte-are promising candidates to replace the ubiquitous lithium-ion battery because of their low cost and the non-toxicity and abundance of sulfur.
However, using sulfur in batteries is tricky for two reasons. First, during the "discharge" cycle, soluble lithium polysulfides (LiPS) form at the cathode, diffuse into the electrolyte, and easily reach the anode, where they progressively degrade the capacity of the battery. Second, sulfur is non-conducting. Thus, a conductive and porous host material is required to accommodate sulfur and simultaneously trap LiPS at the cathode. In the recent past, carbon-based host structures have been explored because of their conductivity. However, carbon-based hosts cannot trap LiPS.
In a recent study published in Advanced Energy Materials, scientists from the Daegu Gyeongbuk Institute of Science and Technology proposed a novel host structure called "platelet ordered mesoporous silica (pOMS)." What is unusual about their choice is that silica, a low-cost metal oxide, is actually non-conducting. However, silica is highly polar and attracts other polar molecules such as LiPS.
[...] Yet, all this considered, perhaps the most important insight to derive from this study is that host structures for LSBs need not be as conductive as was previously thought. Prof Yu says, "Our results are surprising, as no one might have ever thought that non-conductive silica could be a highly efficient sulfur host and even outperform state-of-the-art carbon hosts." This study broadens the selection of host materials for LSBs and could lead to a paradigm shift in realizing next-generation sulfur batteries.
More information: ByongJune Lee et al, Revisiting the Role of Conductivity and Polarity of Host Materials for LongLife Lithium-Sulfur Battery, Advanced Energy Materials (2020). DOI: 10.1002/aenm.201903934
Read more of this story at SoylentNews.