Junior Product Design Engineer

Stealth-mode Battery Startup

Sourced from Stealth-mode Battery Startup's careers site · Posting last seen September 19, 2026

San Jose on site Full time 3+ years exp Posted July 31, 2026
Job description

About the Company

We are a stealth-mode battery startup developing cutting-edge battery technology. Our mission is to revolutionize battery technology to accelerate the global transition to clean energy. By leveraging innovative materials and advanced manufacturing techniques, we are building the future of sustainable energy.

 

Can’t find the company name?

It’s not you, it’s us! We’re really excited about the potential of our technology, product, and mission, and have chosen to remain in stealth mode. If the job description piques your interest, please apply. If your skillset is aligned with what we’re looking for, the team will reach out to schedule your interview and tell you a bit more about us (e.g. who we are).

Role

We are seeking a Mechanical Design Engineer to support the design and development of structural battery hardware (e.g., enclosures, trays, lids/covers) and/or provide engineering support equipment (fixtures, test-bucks, test setups, and prototype/demo manufacturing equipment).

You’ll work closely with senior engineers and cross-functional partners (analysis, test, manufacturing) to translate concepts into hardware that meets performance, reliability, and manufacturability needs.

Responsibilities

Mechanical Design & Product Development

  • Support design of structural components for HV battery packs such as enclosures, trays, covers, and related brackets/interfaces under thermal, mechanical, and environmental constraints

  • Create and iterate 3D CAD models and assemblies; contribute to design trades (weight, stiffness, cost, manufacturability) with guidance from senior engineers.

  • Apply DFM/DFA fundamentals in part and assembly design (fasteners, sealing concepts, stack-ups, serviceability).

  • Produce 2D drawings with clear notes, basic GD&T, and manufacturing intent; support tolerance studies as needed.

  • Provide directional guidance through simulations to steer the design and architecture when dedicated CAE resources are limited.

  • Develop comprehensive 2D drawing packages applying appropriate GD&T and conduct tolerance analyses to ensure assembly integrity and performance.

Fixtures, Bucks, and Prototype/Test Equipment

  • Design and develop fixtures, bucks, test setups, and prototype/demo pack manufacturing equipment to support proof-of-concept builds and validation.

  • Help maintain and improve existing fixture designs (updates, repairability, usability, documentation).

  • Work with standard fixturing components and vendor catalogs; select appropriate hardware and mechanisms.

Hands-On Build Support & Collaboration

  • Partner with manufacturing/shop resources during fabrication, prototype builds, and assembly debug—bringing a “design it, build it, improve it” mindset.

  • Coordinate with suppliers for quotes, DFM feedback, and part delivery; assist with incoming inspection and fit/function checks.

  • Support test activities (vibration/structural/environmental) and document findings; assist in root-cause investigations and corrective actions.

Validation & Testing

  • Support component and system-level validation, including vibration, structural, and environmental testing.

  • Support in validation, durability, and abuse testing activities to ensure performance and reliability.

  • Drive root-cause analysis and corrective actions for mechanical performance issues.

Qualifications

  • B.S. in Mechanical Engineering (or related), or a technical diploma in Mechanical Technology/CAD with equivalent hands-on experience.

  • 3+ years of mechanical design experience (product, structures, automation equipment, fixtures, or custom machinery).

  • Proficiency in 3D CAD (SolidWorks, Inventor, NX, CATIA, or similar).

  • Experience producing 2D drawing packages; familiarity with GD&T concepts and tolerance stack-up basics.

  • Working knowledge of fabrication/manufacturing methods (machining, sheet metal, welding, fastening, bonding) and how they influence design decisions.

  • Comfortable in fast-paced, iterative development environments; strong communication and documentation habits.


Preferred Qualifications

  • Experience with HV battery systems and structural designs (or adjacent structural systems like automotive body/chassis).

  • Familiarity with manufacturing processes such as machining, injection molding, 3D printing, and extrusions.

  • Exposure to FEA/structural analysis tools (ANSYS, Abaqus, LS-DYNA, etc.) at a basic level (interpretation/collaboration vs. ownership).

  • Knowledge of design release workflows for mechanical parts and assemblies.

  • Comfort working with electro-mechanical designs.


Why Join?

  • Innovative Technology: Work on cutting-edge energy storage solutions that power the future.

  • Career Growth: Opportunities to work on high-impact projects and advance in a growing industry.

  • Competitive Benefits: Comprehensive health, wellness, and professional development programs.

  • Mission-Driven Culture: Be part of a team that is shaping the future of sustainable energy through innovation and excellence.

Skills

  • CAD
  • GD&T
  • fabrication methods
  • design development
  • prototype support
  • HV battery systems
  • manufacturing processes
  • FEA analysis
  • design release workflows
  • electromechanical design
  • mechanical design
  • DFM
  • DFA
  • structural analysis
About this role

Summary

Design and develop battery hardware, fixtures, and test equipment; collaborate across teams.

Job title

Junior Product Design Engineer

Experience

3+ years

Industry

battery technology

Location

San Jose, CA · On-site

Salary

Pay not disclosed by employer

Management role

No

Posting history
  1. Jul 31, 2026 First posted
  2. Jul 31, 2026 Live now

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