Technology

Today's growing need for energy storage as related to renewables, electric/hybrid vehicles, consumer products, and government applications drives the requirement for a radical change in battery design and production. In order to achieve such critical requirements in lithium battery performance, researchers in the Department of Chemistry at Colorado State University have designed a revolutionary battery architecture intended to address the slow diffusion of lithium ions (Li+) into and between the anode and cathode. This patent-pending architecture is designed around a nanowire array of anodes, conformally coated by an ultra-thin polymer electrolyte and then surrounded by a cathode matrix. The result is a three-dimensionally structured lithium-ion battery composed of interpenetrating, nanometer scale electrodes with extremely short Li+ diffusion distances and a power density that is orders of magnitude greater than comparable two-dimensional architectures in use today, and under development for future applications. Furthermore, the use of copper antimonide (Cu₂Sb) nanowires lends an unprecedented degree of stability to the anode and has already demonstrated virtually no loss of capacity over extensive cycling - a dramatic improvement over other anode materials. Such materials, and the underlying technologies described herein readily lend themselves to low cost manufacturing and production scale-up.

The realization of this sophisticated battery required the development of myriad cutting-edge enabling technologies. At the heart of this product is a patent-pending technology for the fabrication of the Cu2Sb nanowires. Using a novel electrodeposition method, Cu2Sb may be directly deposited as polycrystalline, intermetallic nanowires without the costly requirement of further annealing or other post-treatments. Additionally, this technique ensures continuous electrical contact throughout the 3D anode. Similarly, the fabrication of the electrolyte layer is accomplished through an electrochemical polymerization method - specifically designed to uniformly encapsulate the entire conductive surface of the anode. The electrolyte is kept extremely thin to allow for the subsequent interpenetration into the structure by the cathode material and is anticipated to be extraordinarily insulating and pin-hole free. The strict demands on the electrolyte form the basis for additional intellectual property protection.