Test Automation Engineer Intern - Fall 2026

Redwood Materials•San Francisco, CA

4d•$41 - $48

About The Position

Redwood Materials is localizing a global battery supply chain that seamlessly integrates recovery, reuse, and recycling — keeping critical minerals in circulation and driving the energy transition. Founded in 2017, we’re delivering low-cost and large-scale energy storage and producing battery materials in the U.S. for the first time, all from batteries we already have. Redwood Energy is building some of the fastest, lowest-cost energy storage in the U.S. from both new battery modules and second-life EV packs. Second-life hardware arrives with a history — different chemistries, capacities, and states of health — and every unit has to be proven safe and reliable before it ships. That proof comes from test: the automated systems that exercise the firmware and electronics inside our products and decide whether they're ready for the field. Our test engineering team builds those systems — the test stands on the production floor, the hardware-in-the-loop benches that validate firmware releases, and the CI pipelines that tie them together. As a Test Automation Engineering Intern, you'll work alongside our engineers building the next generation of this test capability. You'll write Python that drives real instruments and real battery hardware, help bring up new test stands from the bench up, and debug failures where the root cause could live in the test code, the firmware, or the unit under test. This is a great opportunity to apply what you've learned in coursework to production test systems, with mentorship from experienced engineers along the way.

Requirements

Currently pursuing a BS or MS in Electrical Engineering, Computer Engineering, Computer Science, Mechatronics, or a related field.
Working proficiency in Python, including comfort reading and modifying a codebase you did not write.
Experience writing automated tests with pytest or a comparable framework, from coursework, projects, or prior internships.
Experience with Git and a pull-request-based development workflow.
Solid grasp of circuit basics — voltage, current, resistance, and power, and how they relate — sufficient to predict what a measurement should read and recognize when it doesn't.
Able to read a schematic, wiring diagram, or datasheet and act on it; hands-on experience working safely around energized equipment — power supplies, loads, or battery hardware — from lab work, projects, or prior internships.
A safety-conscious mindset, strong attention to detail, and eagerness to learn how production test systems are built.

Nice To Haves

Familiarity with CAN, Modbus, SCPI, or other instrument and industrial protocols is a plus, even if only from classwork or personal projects.
Familiarity with the Linux command line is a plus.

Responsibilities

Write and maintain Python test automation for firmware and hardware validation, using pytest and our internal test frameworks.
Develop drivers and tooling for programmable power supplies, electronic loads, data acquisition, and switching hardware over protocols like SCPI, CAN, and Modbus.
Help bring up new test stands — from fixtures and wiring through the software that sequences them — as we expand our validation capability.
Investigate real failures on real equipment, using CAN traces, instrument logs, and bench tools to determine whether the fault lies in the test code, the fixture, or the unit under test.
Add regression coverage to our CI pipelines so firmware changes are validated automatically rather than by hand.
Contribute to documentation and test processes that support taking test systems from prototype toward production.
Own a scoped project end to end and present your results to the engineering team at the close of the internship.