Mechanical Design Engineer

London / Hybrid

IONATE is a deep tech scale-up building the hardware and software backbone for smart grids. Our mission is to transform power systems - from grids and microgrids to renewables and data centres - unlocking the massive potential in this under-innovated sector that touches every aspect of our modern lives.

Our team is looking for a Mechanical Design Engineer who will be responsible for developing next-generation mechanical systems from concept to series production. Requiring previous hands‑on experience in mechanical design, test and manufacturing, this position will involve working across our hardware team, focusing on inverter design and thermal cooling systems with a high degree of electro‑mechanical integration.

You will need an innovative approach to engineering with well‑grounded reasoning and drive for continuous improvement. Importantly you will contribute to live ongoing projects and work with the team to continue developing our HIT technology.

What you will do:

• Work in close tandem with power electronics and electrical engineers to design next‑generation mechanical assemblies for inverters, switchgear, control, and protection equipment.
• Design and develop cabinet enclosures, electro mechanical interfaces, and custom components, working closely with manufacturing partners and designers.
• Architect, build and test air‑to‑air and liquid‑to‑air cooling systems for high‑power components and power modules.
• Use our well‑equipped workshop to build and test new prototype concepts.
• Participate in hands‑on design validation and testing in the lab/workshop and field environments as part of our multi‑disciplinary team.
• Be responsible for hardware and component selection, working alongside procurement specialists to maintain BOMs and manage supply chain risks.
• Create and maintain documentation including requirements documents, testing reports, data packs for manufacturing and installation manuals.

• Industrial experience in mechanical engineering, ideally in a high‑tech R&D or start‑up environment.
• A bachelor’s degree in mechanical engineering, or a related discipline.
• Strong 3D CAD skills and experience producing production drawings and maintaining large assemblies.
• Hands‑on prototyping experience (e.g. hand tools, sheet metal, 3D printing, assembly).
• Simulation experience using FEA and CFD software tools for design validation.
• Excellent communication and interpersonal skills to collaborate effectively within cross‑functional teams.
• Ability to work in a fast‑paced and dynamic start‑up environment 3-5 days per week depending on project deadlines.
• Willing to travel nationally and internationally when required for testing/commissioning (up to 10% annually).

It would be useful to have:

• Experience building systems for harsh environments with temperature differentials, high humidity, and dusty conditions, working to IP or NEMA standards.
• Solid understanding of sheet metal part design and manufacturing techniques.
• Practical experience with GD&T, tolerance stack‑up analysis and BS888 standard.
• Hands‑on experience in designing and testing systems to achieve UL/TUV certification for commercial readiness.
• High‑level understanding of electrical concepts and exposure to power electronics.

• Employee Option Plan: You getequity in IONATE, so as we succeed so do you.
• Private Medical & Dental Insurance: From day one, we provide you with full, comprehensive private medical and dental cover through Bupa. You also have the option to add any dependents to your cover. Please ask us for more details.
• Company pension: a flexible, and sustainable pension product to help you plan for your future.
• Career Development:It’s important to us that you have the opportunity for ongoing professional development and career growth. You will receive an annual budget for professional development and work with your team to set and reach goals every year.
• Flexible working schedules: You will be based in our modern West London offices and have the flexibility for hybrid work‑from‑home arrangements. Talk to us at the application process about this.
• Cycle to Work Scheme: Low carbon travel is important for everyone, so we have in place a cycle scheme to help you purchase a bicycle.
• Slow travel: We believe in a low carbon future, so if you wish to travel by a lower carbon method – but it takes much longer than flying - we will give you an extra 2 slow travel days per year.