Zeta Energy and Huntsman Corporation announced today that they have demonstrated an advanced lithium-sulfur battery that requires no copper or aluminum as current collectors, thus enabling further enhancement in energy and power density. This is an important innovation as both the U.S. Department of Energy and the World Materials Forum have designated copper as a "critical material" based on its importance to energy technologies, known reserves, and risk of supply chain disruption.
Zeta Energy's lithium-sulfur batteries had already eliminated the use of recognized critical materials nickel and graphite, manganese, and cobalt (a critical material with extreme socio-political hazards as well as volatility in supply and price). This cooperative development by Zeta Energy and Huntsman is thus a major step forward in sustainable battery production.
Notably, by replacing copper or aluminum foil with carbon-based current collectors, this lithium-sulfur battery can further increase the energy density achieved by Zeta Energy's lithium-sulfur batteries. Management at Zeta Energy indicated that at this time the copper-free batteries would be designed for special purpose applications, but that the technology portends the possibility of entirely metal-free batteries in the future.
"On the anode side, we can grow vertically aligned carbon nanotubes without a metal current collector and deposit lithium over and between the carbon nanotubes", said Chief Technology Officer Abdul Raji. "We can also make the sulfurized carbon cathode without a metal current collector."
MIRALON® carbon nanotube materials are known as lightweight and effective current collectors, but the Zeta Energy team was pleased by additional benefits the Huntsman product brought to the project. "The initial purpose of incorporating carbon-based current collectors was further weight reduction in the cells, however, these materials additionally emerged as a promising solution for other unique advantages for Li-S batteries, therefore extending the scope of its applications. This metal-free current collector technology serves as a key enabler for cells with energy density exceeding 500 Wh/kg as part of our development program." says Chief Science Officer Rodrigo Salvatierra.
Huntsman's MIRALON® Commercial Director John Fraser added, "Huntsman is excited to be part of this innovative and critical metal-free battery development and look forward to supporting Zeta Energy in growing their lightweight, high energy-density offering for the battery market."