Yu-Sheng's talk at ECS 222nd PRiME meeting - Li-S Batteries
Introduction
Faced with the reality of limited fossil fuel resourcesand their environmental consequences, use of lithium-ionbatteries as the onboard energy storage for vehicles isdrawing much attention. However, the high cost, safetyconcerns, and limited energy density associated with thecurrently available insertion-compound electrodes remainto be an impediment to adopt them. Development ofalternative low-cost cathode materials with high energyand power densities is critical for successfully utilizingthe lithium-ion technology for vehicle applications.Rechargeable lithium-sulfur batteries are attractive inthis regard as sulfur is abundant and exhibits an order ofmagnitude higher theoretical capacity (1675 mAh g-1)compared to the currently used cathodes. However, pooractive material utilization, rate capability, and cyclabilityresulting from the high electrical resistivity of sulfur anddissolution of intermediate polysulfides (Li2Sx with 2 < x≤ 8) into the electrolyte during cycling remain to be majorobstacles to employ the Li-S batteries. With thisperspective, we present here a self-weaving sulfur/multiwallcarbon nanotube (MWCNT) composite cathodeswith unique structural/morphological features andoutstanding performance advantages for high-raterechargeable lithium-sulfur batteries.
