Polymer coating lightens the load for Li batteriesS. Himmelstein | December 08, 2023
Lithium-sulfur (Li-S) batteries are highly efficient, delivering more energy per gram than Li-ion batteries. However, the need to extract and transport Li incurs a significant environmental footprint and highlights the desirability of reducing the amount of this metal required in a single battery. A new design developed by researchers in Australia addresses these issues with a nanoporous polymer-coated Li foil anode that cuts the amount of Li needed in a battery that delivers a longer service life.
Researchers from Monash University and RMIT University demonstrated that the thin poly(trimethylsilyl)propyne polymer coating applied directly to the Li foil anode significantly improved the number of times the battery could be cycled. Treated anodes were characterized by 5.7 times more dense Li over controls and increased the capacity retention responsible for improved cycling performance.
The coating also serves as a scaffold for Li, and helps it charge and discharge repeatedly. The polymer contains tiny holes less than a nanometer in size to allow Li ions to move freely while blocking other chemicals that would strain or degrade the metal. The redesigned battery maintained a capacity in excess of 660 mAh/mg during more than 250 cycles and a S loading of 4 mg/cm2.
This sustainable Li-S battery design is described in Advanced Sustainable Systems.