The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project advances battery technologies for electric vehicles and related applications. The proposed project advances beyond the current Lithium-ion (Li-ion batteries by demonstrating a cost-effective and scalable process to manufacture high-purity, defect-free Lithium (Li) metal electrodes with superior cycle life. Lithium metal batteries promise substantially higher energy density than Li-ion batteries, and have a compelling value proposition for electric vehicles and portable electronics applications. The proposed technology addresses so-called "range anxiety" in electric vehicles, enabling use of these batteries for ranges exceeding 300 miles. This SBIR Phase I project proposes to investigate large area Li-metal thin films deposition with high microstructural and compositional uniformity by overcoming Li-ion concentration gradients in the electrolyte. The project proposes to develop superior Li-metal anodes with the aid of an electrochemical flow reactor to overcome the electrolyte-phase mass transfer limitations. Though reproducibility and uniformity of the thin film anodes is not a concern at electrode areas less than 3-cm2, scaling up to areas exceeding 25 cm2 for commercial pouch cell format can lead to non-uniform and dendritic/mossy morphology, resulting in capacity loss and poor cycling life. A large-area electrochemical flow reactor will be assembled and the process parameters for high-performance Li thin film anodes will be established, producing films with high purity (> 99.99%) and controllable thickness (5-50 micron) with a form factor greater than 25 cm2. The key innovation is an electrochemical flow reactor to produce high-performance lithium metal electrodes using low-cost water-based mineral feedstocks at a commercially viable scale. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.