Senior Power Electronics Engineer, Energy Storage

About Redwood Materials Redwood Materials was founded in 2017 by JB Straubel, co-founder and former CTO of Tesla, on a simple but radical idea: the critical minerals powering the energy transition already exist. They just need to come back. Today Redwood is the largest lithium-ion battery recycler in North America — recovering, refining, and redeploying critical minerals from end-of-life batteries back into the supply chain. On the energy side, Redwood has deployed the largest second-life battery project in the world, delivering power to AI data centers in months rather than years using proprietary energy architecture engineered entirely in-house. The company is profitable, the market it operates in is projected to grow 20 to 50 times over the next decade, and Redwood is the only company with the supply chain, the technology, and the operational scale to lead it. As a Power Electronics Engineer for Energy Storage, you will develop Redwood’s next-generation Battery Energy Storage Systems (BESS). In this role, you will design advanced power converters that interface with battery packs, battery modules, photovoltaic (PV) systems, and the grid for large-scale energy storage applications, including AI datacenters. This role involves solving practical circuit- and system-level challenges in converter topology, power-stage component selection (e.g., MOSFETs and magnetics), PCB/PCBA design, thermal analysis, integration, and validation. In addition, you will work with a variety of cross-functional teams such as ME, FW/Control, System, Compliance, Supply Chain, and Manufacturing teams. At Redwood, we build high-efficiency, high-reliability, and low-cost BESS solutions using repurposed batteries, creative engineering approaches, and vertical integration. This creates a unique and rewarding set of technical challenges for engineers who enjoy solving complex power electronics problems. Responsibilities Design high-voltage (800V–1.5kVdc, 480–800Vac) and high-power (10kW–200kW) converters tailored for utility-scale BESS and industrial infrastructure. Conduct comprehensive topology comparison and trade-off analyses evaluating efficiency, power density, cost, and manufacturability. Perform power-stage component sizing and Si/SiC MOSFET selection based on loss modeling and thermal management. Design robust gate driver circuits and dedicated gate driver power supplies to ensure safe, high-frequency switching operations. Lead the design, modeling, and specification of custom magnetic components, including transformers and inductors utilizing Litz-wire or PCB-winding architectures. Architect the low-voltage (LV) subsystem, including auxiliary power supplies, sensing circuitry (voltage/current/temperature), and hardware-level protection. Design and optimize EMI filters, including differential-mode and common-mode inductors, X/Y-caps, and damping elements. Drive high-voltage, high-power PCB/PCBA layout design, ensuring clearance/creepage…