About this Senior Manufacturing Engineer role at ON.energy
ON.energy is building the power infrastructure that makes the AI era possible. As AI demand surges past what the grid and traditional data centers can support, ON.energy provides a new class of power technology proven at gigawatt scale and trusted by the world’s leading cloud and AI companies. Our systems are already deployed across 2.5 GW of hyper-scale campuses, validated by top U.S. national labs, and certified for grid-safe operation by major utilities. With real products in the field, we’re scaling faster than the grid can, transforming power from a bottleneck into a competitive advantage for the companies building the future.
ON.energy is building the power infrastructure that makes the AI era possible. As AI demand surges past what the grid and traditional data centers can support, ON.energy provides a new class of power technology proven at gigawatt scale and trusted by the world’s leading cloud and AI companies. Our systems are already deployed across 2.5 GW of hyper-scale campuses, validated by top U.S. national labs, and certified for grid-safe operation by major utilities. With real products in the field, we’re scaling faster than the grid can, transforming power from a bottleneck into a competitive advantage for the companies building the future.
The Role
The Manufacturing Engineer owns the "design-to-line" translation for On.Energy's integrated products — turning BESS enclosures, power conversion equipment, and UPS/microgrid assemblies into repeatable, scalable, manufacturable builds. You will define assembly processes, tooling, work instructions, and test checkpoints for products built both in-house and at contract manufacturers (CMs), and you will drive the continuous improvement of yield, cycle time, and cost.
This role sits at the intersection of electrical, mechanical, and controls disciplines. You should be comfortable moving between a battery module's electrical interfaces, a switchgear/UPS cabinet's power path, and the mechanical fit-up of an integrated enclosure — and equally comfortable on the shop floor solving a real build problem.
What You'll Do
- Develop and document manufacturing processes, assembly sequences, and standard work instructions for BESS enclosures, DC subsystems, power conversion systems (PCS), and medium-voltage UPS/microgrid assemblies.
- Lead Design for Manufacturing and Assembly (DFMA) reviews with product and design engineering to improve manufacturability, reduce part count, and drive down cost before designs are released.
- Define and validate station-level requirements: workstations, tooling, fixtures, torque and crimp specs, cabling and busbar routing, and material flow across the line.
- Establish production readiness and manufacturing-readiness milestones for new products and product changes, including in-process (IPQC) and end-of-line (EOL) test checkpoints.
- Specify and commission functional and safety test procedures — insulation/dielectric (hipot), continuity, BMS communication, PCS/UPS functional test, and integration with On.Command™ controls and telemetry.
- Partner with contract manufacturers on process transfer, first-article inspection (FAI), production ramp, and ongoing process control; travel to CM and field sites as needed.
- Drive root-cause analysis (8D, 5-Why, fishbone) on quality escapes and line stoppages, and implement corrective/preventive actions.
- Lead continuous-improvement initiatives using Lean and Six Sigma methods (value-stream mapping, kaizen, SPC) to improve yield, throughput, and cost per unit.
- Own engineering change management (ECN/ECO) from the manufacturing side, including bill-of-material (BOM) accuracy, routings, and configuration control in the ERP/PLM system.
- Support production capacity planning, line balancing, and takt-time analysis to meet build schedules.
- Champion a safety-first culture on the floor: LOTO, arc-flash and high-voltage/medium-voltage safe work practices, and ergonomic workstation design.
What You'll Bring
- Bachelor's degree in Mechanical, Electrical, Manufacturing, or Industrial Engineering (or equivalent experience).
- 3+ years of manufacturing/process engineering experience with electromechanical products — energy storage, power electronics, UPS, switchgear, electric vehicle, or similar high-voltage/high-power hardware strongly preferred.
- Hands-on knowledge of assembly processes for electrical cabinets and enclosures: wiring/harnessing, busbar and cable termination, connectorization, and panel build.
- Working understanding of power systems fundamentals — DC battery systems, PCS/inverters, and AC power distribution/UPS — and the safety practices that go with them.
- Proficiency with DFMA principles, GD&T, and reading electrical schematics and mechanical drawings.
- Experience creating work instructions, process FMEAs, control plans, and test procedures.
- Familiarity with Lean Manufacturing and Six Sigma (Green Belt or higher a plus).
- Experience working in an ERP/PLM environment (e.g., SAP, Oracle, Arena, Windchill) for BOMs, routings, and change control.
- Strong problem-solving skills, disciplined documentation habits, and the ability to work cross-functionally across engineering, quality, supply chain, and operations.
- Willingness to travel (typically up to ~25%) to contract manufacturers, suppliers, and project/field sites.
Nice to Have
- Experience with battery module/pack integration, BMS interfaces, and thermal management.
- Experience with medium-voltage equipment and microgrid or UPS integration.
- Knowledge of relevant standards: UL 9540 / UL 9540A, UL 1741, IEC 62933, NFPA 70/70E, and applicable UPS standards (e.g., UL 1778 / IEC 62040).
- Experience standing up a new production line or transferring a product to a contract manufacturer.
- Familiarity with test automation, data acquisition (e.g., LabVIEW), and EOL test system development.
For US-based roles - What you’ll get:
- Competitive salary + annual performance-based bonus eligibility
- Medical, dental, and vision insurance
- 401(k) with company match
- Paid time off and company holidays
For Mexico-based roles - What you’ll get:
- Competitive salary + annual performance bonus eligibility
- Christmas Bonus (Aguinaldo): 30 days
- Major medical expenses and life insurance
- Paid time off and holidays (per local policy)
For all roles:
- Professional development and growth opportunities
- Opportunity to grow with a mission-driven team shaping the future of clean energy
- Equal Opportunity: ON.energy is committed to equal employment opportunity and to maintaining a work environment free of harassment, discrimination, or retaliation.
- Accommodations: If you need an accommodation during the application process, email recruitment@onenergystorage.com
- Benefits vary by role and location and are subject to change.