Senior Mechanical Engineer - Li-ion Battery Cell Development (Cell Design)

Purpose of the Role

Location: Oxford, UK

Department: Cell Technology / Cell Design

Reports to: Head of Cell Design – Cell Technology / Cell Development

Line Management: 4 direct reports

The Opportunity

Agratas is building one of the world's most advanced and sustainable battery businesses — and we’re looking for a Senior Mechanical Engineer to help shape the next generation of Li-ion battery cells. In this role, you’ll lead the mechanical design and development of cell components, driving improvements in performance, safety, and manufacturability. Working closely with R&D and process engineering teams in a fast‐paced prototype environment, you’ll play a key part in taking innovative concepts through to scalable pilot‐level production.

Why Agratas

At Agratas, we’re accelerating the global transition to clean energy by developing cutting‐edge battery technologies and world‐class manufacturing capabilities. Joining us means working with industry experts, solving complex engineering challenges, and contributing to products that will power the future of mobility and energy storage. We foster a culture of innovation, collaboration, and continuous learning — where your ideas genuinely shape what comes next.

What You’ll Do

• Lead the mechanical design and optimisation of Li-ion battery cell components (substrates, tabs, can hardware, etc.) to meet performance, energy density, and cycle life targets.
• Evaluate and select materials based on mechanical, thermal, and electrical characteristics, cost, and manufacturability.
• Collaborate with process engineering to transition designs from lab‐scale prototypes to pilot‐scale manufacturing.
• Create and release detailed mechanical drawings and assembly specifications.
• Lead cross‐functional design reviews and deliver technical communications supporting go/no‐go decisions.
• Integrate DFM principles, including stack‐up analysis and DMA, to improve manufacturability, yield, and cost efficiency.
• Identify and implement innovative solutions to enhance performance, safety, and scalability.

What You Bring

• Deep understanding of Li-ion battery cell architecture and mechanical performance requirements.
• Experience deriving and validating mechanical requirements from higher‐level systems (module, pack, vehicle).
• Strong background in CAD design, GD&T, and developing specifications for complex assemblies.
• Familiarity with APQP milestones and experience supporting DFMEA.
• Hands‐on experience with component-level testing, vendor engagement, and ensuring parts meet specification.
• Experience with ultrasonic welding is highly desirable.
• Strong materials science knowledge relevant to energy storage applications.
• Proficiency in FEA, CFD, stack‐up modelling, and CAE tools for simulation and analysis.
• Strong analytical and problem‐solving skills, including root‐cause failure analysis.
• Excellent communication and collaboration skills across engineering and product teams.
• PhD in Mechanical Engineering or a related discipline, or equivalent experience in Li-ion battery development.

Leadership

• Experience mentoring junior engineers.
• Strong stakeholder management skills with the ability to build credible, positive working relationships across diverse teams.

Equal Opportunity Statement

Agratas is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We welcome applications from candidates of all backgrounds, experiences, and perspectives, and ensure fair and equitable treatment throughout every stage of the hiring process.

Job Details

• Seniority level: Mid‐Senior level
• Employment type: Full‐time
• Job function: Engineering and Information Technology
• Industries: Renewable Energy Equipment Manufacturing