By employing a novel nitrogen-doped porous carbon material researchers have dramatically improved the charging speed of lithium-sulfur batteries, addressing their slow charging speeds that has hindered their widespread commercialization.
In addition to slow charging rates, sulfur-lithium battery is often degraded by the formation and migration of lithium polysulfides during the discharge process. To address these compounds batteries have been developed that incorporates sulfur in porous carbon structures, however they have yet to achieve the performance necessary for commercialization.
To address these concerns researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST) synthesized a highly graphitic multiparous carbon material doped with nitrogen that was applied to lithium-sulfur battery cathodes. During their testing, which is published in ACS Nano, the batteries which utilized this multifunctional carbon material achieved a capacity of 705 mAh g⁻¹, a 1.6 fold increase over conventional batteries. Additionally, by doping the carbon surface with nitrogen, lithium polysulfide migration was effectively reduced allowing for an 82% capacity retention even after 1,000 charge discharge cycles.
"This research focused on improving the charging speed of lithium–sulfur batteries using a simple synthesis method involving magnesium. We hope this study will accelerate the commercialization of lithium–sulfur batteries," concluded Professor Jong-sung Yu of DGIST.