Overcoming Key Challenges for a Viable Lithium-Sulfur Transportation Battery

The lithium-sulfur electrochemistry is viewed as an attractive electrical energy storage system for transportation applications because of projections of system level energy density and specific energy in excess of state-of-the-art lithium ion technology. The current lack of a low cost ($100/kWh), high performance (400 Wh/L, 1000 cycle) Li-S battery technology is the consequence of limits imposed by several key materials science challenges that must be overcome to move this technology forward. A recent material-to-system analysis demonstrates that the most direct path to increased energy density and low cost is through the reduction of the electrolyte volume fraction (with respect to sulfur) and a reduction in excess metallic lithium [1]. Reduced electrolyte volume fraction requires developing knowledge of how sulfur redox chemistry is altered under lean or starved electrolyte conditions; including electrochemical limits to capacity, the spatial distribution and properties of solid discharge products, and occlusion of sulfur. Reduced Li metal excess requires science informed strategies for protecting the anode against parasitic reaction and maintaining dimensional control during Li electrodeposition and dissolution. The Joint Center for Energy Storage Research (JCESR) has assembled a multidisciplinary team to conduct the necessary science, translate this knowledge to test platforms, develop data fed performance models, and demonstrate progress through cell prototypes [2]. The goal of this presentation is to communicate JCESR’s current progress on these challenges and to provide perspective on where achievable performance will likely be pinned by select fundamental limits.

This work was supported as part of the Joint Center for Energy Storage Research, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences. Sandia is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. DOE’s NNSA under contract DE-AC04-94AL85000.

 

1. D. Eroglu, K.R. Zavadil, K.G. Gallagher, “Critical Link between Materials Chemistry and Cell-Level Design for High Energy Density and Low Cost Lithium-Sulfur Transportation Battery,” J. Electrochem. Soc., 2015, 162 (6), A982-A990.

2. G. Crabtree, “The Joint Center for Energy Storage Research: A New Paradigm for Battery Research and Development”, AIP Conf. Proc., 2015, 1652, 112-128.