High Rate, Long Cycle Life Lithium Sulfur Batteries
Navy SBIR FY2015.2


Sol No.: Navy SBIR FY2015.2
Topic No.: N152-093
Topic Title: High Rate, Long Cycle Life Lithium Sulfur Batteries
Proposal No.: N152-093-0526
Firm: Navitas Advanced Solutions Group
4880 Venture Drive
Ann Arbor, Michigan 48108-2240
Contact: Qingliu Wu
Phone: (734) 205-1403
Abstract: Low cost and high capacity make lithium sulfur batteries (LSB) the next generation of lithium ion batteries. Practical application of LSBs remains limited by low utilization of sulfur and fast capacity fading of sulfur cathodes. The root causes are poor electronic conductivity of the cathode combined with high solubility of intermediate polysulfide products formed during cycling. To overcome these limitations Navitas proposes a new conductive nano-porous ceramic host material for LSB cathodes. This novel composition will provide high affinity to both non-polar sulfur and polar polysulfides. To enhance LSB performance and life: (1) nanoporous structure accommodates sulfur volume change during cycling; (2) mechanical strength and conductivity enables high utilization of sulfur; and (3) high affinity to both sulfur and polysulfides minimizes sulfur dissolution. Phase I will validate the cathode in laboratory prototype full cells. In Phase II, pilot scale electrode coating and cell assembly will be developed to support delivery of at least five prismatic pouch cells >6Ah and >600 Wh/kg. The proposed LSB technology will reduce battery size and cost by 50% vs lithium ion. Applications include most military and consumer devices operating on lithium ion batteries. With improved safety characteristics, aviation applications will be the initial target market.
Benefits: The Navitas LSB cathode technology will provide a competitive advantage to end users through improved battery energy density and cost, reducing the battery size and price vs. established lithium ion batteries. The primary customer will be defense and civilian aircraft in which there is a premium value on battery weight, safety and total cost of ownership. Early adopters will include soldier portable, small unmanned aerial systems and consumer electronics manufacturers who put a premium value on weight or run-time and will accept modest cycle life. As LSB cycle life is extended and costs are reduced through scale-up, the technology will ultimately capture a share of the electric vehicle battery market.

Return