Prototype Engineer (m/f/d) - EFT Mobility AG

This position is based at our subsidiary EFT Mobility AG, located in the center of Munich. You can find more information about EFT Mobility AG HERE.

At EFT Mobility, we are redefining the future of clean, high-performance autonomous flight with next-generation electric power systems tailored for Unmanned Aerial Vehicles (UAVs). Founded in 2019 in Munich by industry veterans from Tesla, BMW, and Siemens, our agile tech company merges deep-rooted expertise with a bold vision for innovation.

We develop batteries, chargers, and power distribution systems, specifically optimized for demanding UAV applications. Our focus is on delivering solutions that achieve industry-leading flight times, power delivery, and reliability. Operating in a fast-paced, startup environment, our highly skilled team thrives on short development cycles, turning groundbreaking ideas into deployed solutions.

We are seeking a versatile, fast-moving, and hands-on Prototype Engineer to lead our early-stage battery and power system development phase. In this role, you will be the bridge between a raw concept and a validated design. You will own the initial rapid prototyping cycle—building the very first physical proofs-of-concept, modifying existing architectures on the fly, and proving that an idea works before the broader development teams are deployed for series production. If you thrive in a dynamic, lab-focused environment where you can build, test, and iterate mission-critical power systems for demanding, real-world defense applications, this is your opportunity.

What is your Day-to-Day Mission:

• Own initial prototype builds for operational validation: Take full responsibility for fabricating the first functional samples of next-generation battery and charger architectures—ranging from integrating novel battery cells into existing pack footprints to assembling initial bench-test proofs-of-concept for new charging systems—ensuring they are safe and ready for immediate flight and field testing.

• Execute prototype design and hardware modifications: Architect and build new power system prototypes from scratch by combining custom electro-mechanical layouts with existing internal building blocks, while also adapting legacy Battery Management Systems (BMS), electronics, and firmware configurations in close collaboration with core Engineering teams.

• Support scaling from proof-of-concept to small series: Provide core engineering design inputs for the next iteration of the battery pack and support the in-house assembly of small-series validation batches.

• Design manufacturing jigs: Conceptualize, design in CAD, and source/fabricate assembly fixtures needed for prototype assembly

• Manage prototyping machinery: Maintain full ownership of the in-house assembly lab equipment, including adhesives and dispensing systems, laser welding setups, 3D printers and Begin-of-Line (BOL) / End-of-Line (EOL) electrical test benches.

• Supervise assembly execution: Guide and collaborate directly with a dedicated workshop technician to execute physical builds safely and efficiently.

• Document and report learnings: Actively close the loop with internal Mechanical Engineering, Electrical Engineering, and Firmware design teams by translating early build learnings, tolerance issues, or mechanical interferences into actionable design improvements.

What you bring to the team:

• Hands-on Prototyping & Workshop Expertise: Proven background in rapid prototyping, electro-mechanical assembly, or workshop-heavy product engineering (preferably within battery systems, high-power electronics, or mission-critical hardware). You possess exceptional practical laboratory skills, including precision soldering, wire-harness fabrication, mechanical assembly, operating 3D printers for quick iterations, and running prototype production equipment.

• Design Skills: Solid proficiency in CAD software (CATIA V5 or similar) for fixture design and rapid product design modifications. Basic comfort with printed circuit board (PCB) designs (Altium Designer or similar) and modifying embedded firmware parameters to adapt existing electronics.

• Resourcefulness & Sourcing Agility: A highly proactive attitude with the ability to independently identify, evaluate, and leverage short-turnaround external suppliers (e.g., CNC machining, rapid sheet metal, 3D printing) to minimize cycle times for custom prototype parts.

• Battery Fundamentals: Strong conceptual understanding of battery architecture, cell handling, weld preparation, and strict battery laboratory safety protocols.

• Analytical Troubleshooting & Debugging: A methodical approach to diagnosing unexpected hardware, mechanical, or firmware behavior in the lab. You enjoy tracing physical or electrical faults on unproven systems and possess the engineering discipline to document root causes clearly for the core design teams.

• Communication: Excellent English communication skills (written and verbal) to collaborate with a cross-functional team of specialists. German language skills are a plus.

Your Benefits:

• Work with purpose: Your contribution to EFT Mobility will help to accelerate the world's transition to sustainable mobility.

• Young and Dynamic Community: Pursue a career you love as part of a young, dynamic, and fast-paced team with flat structures, quick communication, and a ton of daily learnings.

• Develop your career: Join us early on our mission and you will have the opportunity to develop into a leading position in our growing company and the industry. We offer an onboarding program for an ideal start, as well as, clear and personalized development paths.

• Vacation Days: Balance your professional and personal time with generous paid time off (30 days of paid leave a year) for full-time employees.

• Work-life Balance: We aim to provide you with an optimal balance between work and personal life through flexible work options. With your manager's approval, you can enjoy remote work days if your role allows it.

• Lunch Benefit: We promote healthy eating and the well-being of our employees with a monthly lunch budget.

• Mobility Benefit: With our mobility budget, we pay your “Germany Ticket” for work or personal use monthly.