Senior Staff Mechanical Engineer - DC and AC Interconnection, BESS

As a Senior Staff Mechanical Engineer, you will own and drive the mechanical design of DC and AC interconnection systems alongside other mechanical, electrical, and hardware engineers for MW/MWh-scale utility inverter and Battery Energy Storage Systems (BESS) serving data centers, spanning outdoor cabinets and containerized platforms.

This role requires deep, hands-on expertise in the mechanical design of high-voltage DC and AC interconnections — including busbars, cable harnesses, bulkhead connectors, and insulation and barrier systems — for 800V–1500V DC battery voltages and 277/480V AC voltages, with attention to creepage, clearance, insulation, and BESS safety compliance. You will work closely with electrical hardware, system, controls, thermal, sourcing, manufacturing, and quality teams to ensure the product meets safety, performance, reliability, manufacturability, serviceability, and cost targets — delivering production-ready designs from concept through deployment while optimizing BOM cost.

Own and drive the mechanical design of HV DC and AC interconnection systems — busbars, cable harnesses, bulkhead connectors, terminals, and insulation and barrier systems — interconnecting multiple inverter DC inputs to the battery and inverter AC outputs to the grid.

Design custom bulkhead connectors for high-voltage DC (800–1500V) and high-voltage AC (277/480V) applications.

Design busbar and conductor layouts that meet creepage, clearance, insulation coordination, and thermal-expansion requirements.

Integrate and package DC and AC fusing and high-current DC and AC molded case circuit breakers (MCCBs) within the interconnection system.

Develop electro-mechanical solutions for outdoor applications that meet various Ingress Protection (IP) ratings.

Perform product structural analysis across injection molded plastics, aluminum metal extrusions, copper busbars, and other materials.

Conduct FEM/FEA (structural and thermal) on interconnection assemblies under various load, vibration, and thermal conditions.

Support the mechanical aspects of interlocks, protection, sequencing, and poka-yoke (error-proof) connections for high-voltage DC and AC interconnections.

Work in cross-functional teams of system integration, electrical hardware, and mechanical engineers.

Support system architecture, cost-reduction proposals, and failure root-cause analysis.

Prepare and execute test plans for structural and environmental validation (vibration, drop test, impact test, thermal test, thermal cycling, damp heat humidity test, connector reliability, and others).

Conduct failure analysis and root-cause identification.

Support sourcing, manufacturing, and quality teams with mechanical expertise, and lead supplier selection and design reviews.

Generate and review documentation, including concept proposals, analysis reports, component specifications, and review minutes.

Provide technical leadership and mentor senior- and staff-level engineers.

Serve as a DC and AC interconnection mechanical subject matter expert for current and next-generation platforms.

Bachelor's degree in Mechanical Engineering with 12+ years of relevant industry experience, or a Master's degree (Product Design, Mechanical Design, or a related discipline) with 8+ years of relevant industry experience.

Strong fundamentals in engineering mechanics and strength of materials.

Strong fundamentals in FEM/FEA (structural and thermal) analysis — a key requirement.

Proven track record designing high-voltage DC and AC interconnection mechanical systems (busbars, harnesses, connectors) in commercial/industrial products.

In-depth knowledge of creepage, clearance, insulation coordination, and high-voltage mechanical safety for 800V–1500V DC and 277/480V AC systems.

In-depth knowledge of design for manufacture for parts made through injection molding, sheet metal, stamping, extrusion, and machining.

Proficiency with CAD tools (SolidWorks or equivalent) and EPDM.

Working knowledge of standards such as UL 9540/9540A, UL1741, IEC 62109, and NEMA, as well as country-specific standards.

Thorough knowledge of product validation methods (vibration, drop test, impact test, thermal cycling, connector reliability, and others).

Proficiency in tolerance analysis, worst-case analysis (WCA), DPPM, DFMEA/AFMEA, and root-cause analysis for field failures.

Strong technical leadership skills, with the ability to lead programs, influence architecture decisions, and mentor senior- and staff-level engineers.

Clear written and verbal communication, including strong presentation skills.

Experience with high-current busbar and high-voltage connector mechanical design.

Experience in design and sustaining activities on high-volume products (500k+ to 1 million per annum).

Rapid prototyping with 3D printing or high-temperature resin materials.

Field quality improvement and cost reduction through Value Analysis/Value Engineering (VAVE).