This PFI: AIR Technology Translation project focuses on translating low-cost and high energy density lithium-sulfur (Li-S) batteries to fill the need for developing a mass-production method of a key material, a sponge-like carbon nanotube (CNT) bulk, which is called a CNT sponge in this research. The invented Li-S batteries are important because they can deliver up to five times higher energy density compared to current commercial Li-ion batteries that have over 90% market share in various applications including computers, tablets, phones, drones, and electric vehicles. Furthermore, the invented Li-S batteries can be charged and discharged 800 times with high (80~90%) capacity retention, and the price of the raw material (sulfur) is at least 300 times lower than that of cobalt-containing active materials used in Li-ion batteries. Since modern life includes various electronic/electrical devices that have made electrical energy storage indispensable, potential impacts from high energy density and low-cost rechargeable batteries are important. The most important unique feature of the invented Li-S batteries is a high sulfur (active material) loading in the sponge cathode, which allows for storing a large amount of energy in actual battery packs.  The project will result in a continuous bulk-manufacturing method of the sponge for commercial mass-production as well as optimum synthesis conditions to control the pore size and morphology of the sponge.
This project addresses the technology gaps related to mass-production as it translates from research discovery toward commercial application. The high sulfur loading is enabled by the sponge-like porous bulk, serving as an excellent electron transport channel and polysulfide reservoir. The covalently connected CNTs not only provide excellent electron transport channels, but also completely eliminate insulating binders (inactive materials) that are used in typical Li-ion batteries to hold powdery raw materials. To mass-produce the CNT sponge, the researchers will investigate a method of continuously delivering the catalyst to the reaction zone as well as optimum reaction conditions for continuous bulk manufacturing. Then the pore size and surface condition of the CNT will be optimized to maximally accommodate sulfur loadings for higher performances. Finally battery prototypes will be fabricated for testing and comparison with the current commercial Li-ion batteries.
This project will provide graduate students with unique opportunities in the process of technology transfer in addition to technology development such as engaging the students in lab-to-market processes as well as educating how to deliver technical information to business and non-technical consumers. The project engages the Texas A&M Technology Commercialization as well as the Texas A&M Engineering Experiment Station (TEES) Commercialization and Entrepreneurship and TEES Industrial Relations groups to seek licensees and investors for manufacturing commercial products out of the research outcomes.
