Mechanical Engineer, Battery Energy Storage Systems

Our client designs and manufactures intelligent energy storage systems for commercial buildings, supporting more efficient use of traditional and renewable power. Their engineering team develops modular battery technology for dense environments where safety, reliability, and performance matter.

We are hiring a hands-on Mechanical Engineer to design and deliver next-generation Battery Energy Storage Systems (BESS). This role owns mechanical development from concept through production and works across electrical, product, and manufacturing teams to deliver scalable, production-ready hardware.

Success requires strong engineering judgment, ownership, and the ability to translate concepts into manufacturable designs within a fast-moving product environment.

• Design mechanical components and assemblies in CAD, including system packaging for PCBs, batteries, sensors, switches, fuses, lighting, and associated wiring
• Drive cross-functional collaboration between mechanical, electrical, and product teams to improve system design, manufacturability, and cost
• Perform component- and assembly-level analysis and verification to meet performance, safety, reliability, and cost requirements
• Own the engineering bill of materials (EBOM) through development and transition to the manufacturing BOM (MBOM) for production release
• Collaborate closely with internal and external manufacturing partners to optimize designs for manufacturability, assembly, and scalability
• Engage directly with global suppliers and partners during design, validation, and product launch phases
• Define scopes of work and technical requirements to maintain alignment with external vendors
• Manage design documentation, revisions, and release processes within the PLM system
• Support hardware integration, prototype development, root cause analysis, and design iteration
• Contribute across projects and priorities to support overall product execution
• Uses AI tools to support design iteration, simulation, and product optimization.

• Bachelor's degree in Mechanical Engineering or a closely related field.
• Minimum 5 years of experience designing and manufacturing mechanical systems using processes such as sheet metal forming, injection molding, and CNC machining.
• Strong 3D and 2D CAD skills, including GD&T to ASME Y14.5 and worst-case tolerance analysis.
• Demonstrated ownership of mechanical assemblies from architecture and design through production release.
• Solid understanding of mechanical enclosures, structures, and mechanisms integrated with electrical systems.
• Proven ability to translate abstract concepts into prototypes, proof-of-concepts, and production-ready designs.
• Working knowledge of DFMEA and PFMEA methodologies.
• Basic understanding of battery safety considerations related to handling, storage, assembly, and operation.
• Strong communication and collaboration skills with the ability to work independently and drive results across teams.

• Familiarity with product certification processes (e.g., UL, CE, CSA).
• Experience with stationary BESS, industrial switchgear, or similar electromechanical systems.
• Experience managing multiple product SKUs and design baselines within a PLM system.
• Experience with structural and thermal analysis tools and methods.
• Background in customer-facing industries such as consumer electronics or automotive.

• This role is based in Irvine, CA 
• Minimal travel may be required to support company operations.

• Irvine, CA: $120,000 to $145,000 base
• Equity and bonus potential