NANOHYDROCHEM LLC — Department of Energy SBIR Phase II: C54-14a

Description

The development of next-generation materials for Li-ion batteries is a highly significant problem and opportunity with far-reaching implications for the future of energy storage and electrification. Graphite is a known suboptimal anode material due to low charge rates and limited specific capacity. While replacing graphite with silicon increases the specific energy density (Wh/kg) by a maximum of 50%, unstructured silicon suffers from fast degradation due to volume expansion. Therefore, a new class of high-capacity engineered anode material that is scalable and low-cost is urgently needed. NanoHydroChem LLC is developing silicon-dominant anodes for lithium-ion batteries that outperform graphite in lithium storage capacity while managing volume changes during charging by encapsulating silicon nanoparticles in a protective carbon shell. The result is an energy-dense, fast-charging, yet highly scalable solution to reduce the cost of production per watt-hour (Wh) while increasing the range and performance of electric vehicles. A key feature of this technology is that it is 100% drop-in, with no alteration to battery cell manufacturing lines needed to adopt the new chemistry. If successfully developed, the result will be a battery of the same size but with 1.5X the capacity, fast charging capability, and a capacity cost of below $100/kWh, which is on par with the target of automakers and regulatory bodies for 2030. During the Phase I project and in earlier work, NanoHydroChem demonstrated the performance increase and scalability of its production process. A proprietary nanoparticle synthesis process followed by a carbon encapsulation step was developed to produce structured silicon nanoparticles approaching industrial scales. The structured silicon demonstrated a specific capacity 4x that of graphite. Our main objective in this phase II project is to deliver complete Li-ion batteries with a minimum capacity of 2Ah to DoE using our silicon-dominant anode material paired with commercially available cathodes. Based on the lessons learned in the Phase I project, we must accomplish four main tasks to achieve this goal. First, improve our anode active material by passivating the silicon surface and decreasing the carbon layer tortuosity. Second, increase the anode electrode loading by lowering the porosity and binder content. Third, increase the cycle/calendar life by optimizing the electrolyte formulation, formation cycles, and pre-lithiation. Fourth, validate commercial reactors for kilogram-scale production. This work will advance our technology to the stage of commercial investment and the formation of strategic partnerships with the goal of breaking into the $60B electric vehicle (EV) battery market.