Senior Battery Systems Engineer

At Relativity Space, we’re building rockets to serve today’s needs and tomorrow’s breakthroughs. Our Terran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launch capacity. But that’s just the start. Achieving commercial success with Terran R will unlock new opportunities to advance science, exploration, and innovation, pioneering progress that reaches beyond the known.

Joining Relativity means becoming part of something where autonomy, ownership, and impact exist at every level. Here, you're not just executing tasks; you're solving problems that haven’t been solved before, helping develop a rocket, a factory, and a business from the ground up. Whether you’re in propulsion, manufacturing, software, avionics, or a corporate function, you’ll collaborate across teams, shape decisions, and see your work come to life in record time.

Relativity is a place where creativity and technical rigor go hand in hand, and your voice will help define the stories we’re writing together. Now is a unique moment in time where it’s early enough to leave your mark on the product, the process, and the culture, but far enough along that Terran R is tangible and picking up momentum.

The most meaningful work of your career is waiting. Join us.

About the Team:
The Avionics team is responsible for the full lifecycle of Terran R's nervous system — designing, building, testing, installing, and operating the hardware that connects and controls every major electrical system on the vehicle and ground. Engineers are deeply embedded into other functions within Relativity, working closely with propulsion, GNC, fluids, and stage engineering teams to ensure seamless integration and operation.

As a Staff Engineer, you'll help shape Terran R's fundamental avionics architecture, own critical flight hardware, and build and grow the team that delivers it.

About the Role:

You will join the team developing the vehicle's high-voltage battery system and grow into technical ownership of it as a complete product, covering cell, mechanical, thermal, electrical/BMS, and vehicle integration. Early on, you will work closely with experienced battery engineers to learn the current design, its history, and how it flies. Over time, you will take on more of the system's technical direction.

You will be the link between the battery's mechanical and electrical disciplines and the rest of the vehicle. You'll help turn mission and vehicle needs into a clear, traceable battery specification, and help shape the architecture that meets it. This is a hands-on technical role with real cross-functional influence. As the battery team grows, it offers a clear path to technical leadership, including leading other engineers.

Architecture & Requirements Partner with the vehicle and power-system architecture team to define battery requirements from the top down — deriving energy, power, voltage, thermal, mass/volume, and life requirements from mission profile, Con Ops, and power-system needs rather than anchoring on legacy designs

Own and maintain the battery specification — the single source of truth for battery requirements, interfaces, and verification criteria — with full traceability

Drive battery architecture and cell down-selection through documented trade studies (requirement driver options evaluation criteria rationale recommendation), in collaboration with the battery mechanical, test, and BMS engineers

Define and manage interface control (electrical, mechanical, thermal, data) between the battery and the vehicle

Cross-Functional Definition Work with Flight Sciences, Con Ops, and the Criteria team to define the battery's environmental and loads requirements — launch and flight vibration/shock, thermal environments,…