Power Electronics Lead, Battery System

QuantumScape; San Jose (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

QuantumScape in San Jose, CA is seeking a Power Electronics Lead to own the end-to-end power conversion architecture for a solid-state battery platform. You will be the chief engineer for the power stage and the technical decision-maker whose topology choices cascade to every other discipline.

You will define efficiency targets, design magnetics and select semiconductors, guide digital control loops with firmware, and collaborate with battery and PCB teams to ensure EMI-conscious layouts and

Qualifications

• 10+ years designing multi-kW AC-DC or DC-DC power converters that shipped in volume.
• Bachelor’s degree plus 12+ years experience or Master’s degree plus 10+ years or PhD with 8+ years.
• Deep expertise in LLC, PSFB, DAB, CLLC, or equivalent.
• Hands-on magnetics design experience (core selection, winding strategy, loss modeling).
• Experience with digital power control (DSP/MCU-based compensators).
• Track record in server PSU, telecom rectifier, EV onboard charger, or comparable high-density power product.
• Proficiency with simulation tools (PLECS, LTspice, Simplis, PSIM, or equivalent).
• Comfortable leading technical direction and mentoring a cross-functional team.

Responsibilities

• Architect end-to-end power conversion topology (AC-DC front end, intermediate bus, DC-DC output stage, bidirectional battery converter path).
• Lead topology trade-off analysis: LLC resonant, phase-shifted full bridge, hybrid approaches, inline vs parallel sidecar integration.
• Design magnetics (planar transformers, coupled inductors) and select power semiconductors with thermal derating analysis.
• Define and drive efficiency targets and power density goals within a rack/shelf envelope.
• Collaborate closely with firmware/embedded engineer on digital control loop implementation.
• Work with the battery systems engineer to define the charge/discharge path, voltage window, and current limits.
• Design protection circuits and fault response behavior.
• Bring up and validate prototype power stages, perform thermal characterization and efficiency optimization.
• Interface with PCB layout contractor to ensure EMI-conscious layout and power plane integrity.

Skills

Power converters design

Topologies expertise

Magnetics design

Digital power control

High-density power products

Circuit simulation

Team leadership

Education

Bachelor’s degree + 12+ years

Master’s degree + 10+ years

Ph.D. + 8+ years

Tools

PLECS

LTspice

PSIM

Simplis

Typhoon HIL

Job description

QuantumScape is on a mission to transform energy storage with solid-state lithium-metal battery technology. The company’s next-generation batteries are designed to enable greater energy density, faster charging and enhanced safety to support the transition away from legacy energy sources toward a lower carbon future.

About the role:

As Power Electronics Lead, you will own the complete power conversion architecture - from AC mains or 48V DC bus input through regulated output rails, including the bidirectional charge/discharge path for the integrated solid-state battery pack. You are the chief engineer for the power stage and the technical decision-maker whose topology choices cascade to every other discipline on the team.

Why this role matters:

Your architecture decisions define the entire product. Whether the battery sits in-line or on a sidecar bus, whether you go GaN at 48V or Si at 12V, whether the hold-up transfer is sub-millisecond or requires a brief interruption - every downstream engineer builds on top of your choices. This is a rare opportunity to design a power platform from a blank sheet with a technology (solid-state batteries) that fundamentally changes what's possible at rack level.

What you’ll do:

• Architect the end-to-end power conversion topology (AC-DC front end, intermediate bus, DC-DC output stage, bidirectional battery converter path)
• Lead topology trade-off analysis: LLC resonant, phase-shifted full bridge, hybrid approaches, in-line vs. parallel sidecar battery integration
• Design magnetics (planar transformers, coupled inductors) and select power semiconductors (GaN/SiC FETs, diodes) with thermal derating analysis
• Define and drive efficiency targets (97%+ titanium-class at rack load) and power density goals within a lOU or 20U shelf envelope
• Collaborate closely with the firmware/embedded engineer on digital control loop implementation (voltage/current mode compensation, loop bandwidth, phase margin)
• Work with the battery systems engineer to define the charge/discharge power path, voltage window, and current limits for solid-state cells
• Design protection circuits (OCP, OVP, OTP, short-circuit) and define fault response behavior
• Bring up and validate prototype power stages on the bench, iterating through bringup, thermal characterization, and efficiency optimization
• Interface with the PCB layout contractor to ensure EMI-conscious layout, proper creepage/clearance, and power plane integrity

Skills you’ll need:

• 10+ years designing multi-kW AC-DC or DC-DC power converters that shipped in volume
• Relevant Bachelor’s degree plus a minimum of 12+ years of experience or a relevant Master’s degree and 10+ years of experience or a relevant Ph.D. and a minimum of 8+ years
• Deep expertise in at least two converter topologies (LLC, PSFB, DAB, CLLC, or equivalent)
• Hands-on magnetics design experience (core selection, winding strategy, loss modeling)
• Experience with digital power control (working with DSP/MCU-based compensators, not just analog)
• Track record in server PSU, telecom rectifier, EVonboard charger, or comparable high-density power product
• Proficiency with simulation tools (PLECS, LTspice, Simplis, PSIM, or equivalent)
• Comfortable leading technical direction and mentoring a small cross-functional team

Nice to have:

• Familiarity with 48V or high-voltage DC bus architectures
• Experience with bidirectional power converters (critical for integrated battery path)
• Knowledge of OCP Open Rack/ ORv3 power delivery specs
• Prior exposure to battery charging systems (CC-CV profiles, temperature-dependent rate limits)
• Experience with hardware-in-the-loop testing (Typhoon HIL, PLECS RT Box)

ONSITE:

This position is required to work onsite 5 days per week to meet the minimum essential duties and requirements of this position. As an on-site R&D and manufacturing operations organization, in-person face to face interaction is essential to building authentic relationships, trust, teamwork, and collaboration.