General New Energy (GNE) announced a new prototype of a lithium-sulfur (Li-S) battery with an energy density of 700Wh/kg. This development marks a considerable increase in energy density compared to standard lithium-ion batteries. According to GNE, this new Li-S battery offers improvements in both mileage and safety.
Li-S batteries use sulfur as the cathode and lithium metal as the anode. Theoretically, Li-S batteries have an energy density potential of up to 2,600Wh/kg, which is more than five times that of lithium-ion batteries. The use of sulfur is also advantageous because it is abundant, inexpensive, and environmentally friendly, making Li-S batteries a potentially more sustainable option.
Technical challenges have slowed the development of Li-S batteries. One issue is sulfur’s low electrical conductivity, which affects high-rate performance. Another challenge, known as the “shuttle effect,” occurs when lithium polysulfides dissolve into the electrolyte. This causes changes in electrolyte viscosity, reduces ion conductivity, and accelerates the battery’s capacity decay. Additionally, the density difference between sulfur and lithium sulfide leads to volume shrinkage during charge-discharge cycles, which impacts the structural stability of the battery.
Using innovative designs and materials, the GNE team has made progress in addressing these technical issues. They have improved sulfur’s conductivity and ion transport by applying nano-material coatings and adding specific electrolyte additives to reduce the shuttle effect. They have also developed new electrolyte materials that improve both the battery’s lifespan and safety.
