Senior Mechanical Design Engineer

IONATE; Greater London; On-site; GBP 70,000 - 100,000; Full time

Benefits offered by this job

Equity (Employee Option Plan)

Private Medical & Dental Insurance

Company pension

Career Development budget

Flexible working schedules

Cycle to Work Scheme

Slow travel

Job summary

IONATE in London is seeking a Senior Mechanical Design Engineer to develop next‑generation mechanical systems from concept to production, with a focus on inverter design and thermal cooling. You will own design verification, testing, and documentation, work with power electronics and hardware engineers, and drive DFM/DFA and manufacturability improvements.

A bachelor’s degree in mechanical engineering is required, with hands‑on prototyping and strong communication to thrive in our fast‑paced

Qualifications

• Bachelor’s degree in mechanical engineering (or related discipline).
• Strong 3D CAD skills and production drawings for large assemblies.
• Hands-on prototyping and testing experience.
• Experience with DFM/DFA and tolerancing.

Responsibilities

• Oversee the design, verification, and validation of mechanical assemblies and enclosures from concept through production release.
• Collaborate with power electronics and electrical engineers on inverter design and thermal management.
• Provide direction across mechanical design, thermal management, and materials selection.
• Review CAD drawings and tolerance analyses; drive DFM/DFA and resolve complex integration issues.
• Utilize workshop for prototyping and testing of concepts.
• Own engineering documentation, configuration control, and change management.

Skills

3D CAD

Prototyping

DFM/DFA

Cross-functional collaboration

Communication

Supplier/CM management

Testing/validation

Education

Bachelor's degree in mechanical engineering

Tools

FEA/CFD software

Job description

London / Hybrid: 3 - 5 days in office per week

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 centers - unlocking the massive potential in this under-innovated sector that touches every aspect of our modern lives.

Our team is looking for a Senior 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:

• Oversee the design, verification, and validation of mechanical assemblies, and enclosures, ensuring products meet performance, reliability, manufacturability, serviceability, and cost targets from concept through qualification and production release.
• Work in close tandem with power electronics and electrical engineers to design next‑generation inverters, switchgear, control, and protection equipment.
• Provide direction across mechanical design, structural analysis, thermal management, and materials selection.
• Review CAD, drawings, and tolerance analyses - drive DFM/DFA and lead resolution of complex mechanical and integration issues.
• 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.
• Own engineering documentation, configuration control, and change management, ensuring designs meet safety, reliability, environmental, and regulatory requirements.
• 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 for complex mechanical systems.
• Deep understanding of structural design, thermal management, materials, tolerancing, and manufacturability best practices.
• Simulation experience using FEA and CFD software tools for design validation.
• Hands‑on prototyping experience (e.g. hand tools, sheet metal, 3D printing, assembly).
• Excellent communication and interpersonal skills to collaborate effectively within cross‑functional teams.
• Experience managing design partners, contract manufacturers, and suppliers.
• Ability to work in a fast‑paced and dynamic start‑up environment.
• Willing to travel nationally and internationally when required for testing/commissioning.

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.
• 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.
• Solid understanding of air- and liquid‑cooled thermal solutions and system‑level integration (electronics, airflow, cable routing, assembly constraints).
• Employee Option Plan: You get equity 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.