Mechanical Test Engineer Jobs in California (NOW HIRING)

Job Title: Mechanical Test Engineer

Job Description

The Mechanical Test Engineer designs, develops, and validates complex mechanical test beds and environments that accurately simulate real-world operating conditions for advanced battery energy storage systems. This role focuses on mechanical and thermal systems, including HVAC, thermal management, hydrogen and electrolyte management, and air-handling systems for battery components. The engineer collaborates closely with cross-functional teams to translate high-level testing requirements into robust mechanical hardware that identifies failure modes early in the development cycle, directly supporting the scaling of innovative battery technology in a fast-moving organization with a mission-driven culture.

Responsibilities

• Lead the mechanical design of complex test beds from initial concepts through detailed CAD, fabrication, and assembly, ensuring they meet performance, safety, and reliability requirements.
• Design HVAC systems, thermal management systems, hydrogen management systems, electrolyte management systems, and air-handling systems tailored for battery energy storage system (BESS) components.
• Develop test environments that accurately simulate real-world operating conditions for battery packs and auxiliary systems, including pumps, manifolds, and power electronics.
• Translate high-level test requirements into functional mechanical hardware that enables early detection of failure modes and supports design validation.
• Perform airflow analysis, including fan and blower selection, ducting design, and optimization of air-handling paths to achieve desired thermal performance.
• Conduct piping calculations and fluid systems design to ensure proper flow, pressure, and distribution within test setups and supporting mechanical systems.
• Carry out materials stress analysis for high-temperature applications to ensure structural integrity and durability of test fixtures and components.
• Create detailed 3D models and engineering drawings using SolidWorks, including assemblies, subassemblies, and fabrication-ready documentation.
• Perform fluids analysis and CFD studies to evaluate and optimize fluid flow and thermal behavior in mechanical and thermal systems.
• Collaborate closely with Electrical, Controls, and Chemical Engineers to integrate sensors, actuators, and data acquisition hardware into mechanical designs.
• Support derisking and validation activities by iterating on mechanical designs based on test results, failure analysis, and feedback from test and design engineering teams.
• Communicate design intent, technical decisions, and test system performance clearly to cross-functional stakeholders, both verbally and in written form.
• Assist in the assembly, commissioning, and troubleshooting of mechanical test beds and associated systems in an onsite lab or test facility environment.

Essential Skills

• Proven experience in mechanical engineering with a focus on mechanical systems and mechanical design.
• Proficiency in SolidWorks, including 3D modeling, assembly creation, and detailed drawing generation for fabrication and assembly.
• Experience with fluid mechanics and fluid systems design, including piping calculations and flow distribution.
• Hands-on experience with fluids analysis and CFD (computational fluid dynamics) for evaluating fluid flow and thermal performance.
• Experience in thermal analysis and thermal systems design, including airflow analysis and component specification such as fans and blowers.
• Ability to design and analyze HVAC systems, thermal management systems, hydrogen management systems, electrolyte management systems, and air-handling systems.
• Experience performing materials stress analysis, particularly for high-temperature environments and components.
• Familiarity with integrating electronics, sensors, actuators, and data acquisition hardware into mechanical designs.
• Strong communication skills, with the ability to work effectively in cross-functional teams and explain complex mechanical concepts clearly.
• Capability to take designs from conceptual CAD through to fabrication, assembly, and validation in a test environment.

Additional Skills & Qualifications

• Experience designing test beds or test environments for battery packs, pumps, manifolds, and power electronics.
• Experience in supporting derisking and validation activities by translating high-level testing requirements into practical mechanical hardware.
• Exposure to battery energy storage systems (BESS) or related energy, power, or thermal management applications.
• Experience working closely with Electrical, Controls, and Chemical Engineers on integrated systems.
• Interest in contributing to the scaling of breakthrough battery technology and working in a fast-moving, mission-driven organization.

Work Environment

This role is based onsite in Berkeley in a hands-on engineering and test facility environment. The Mechanical Test Engineer works directly with physical test beds, mechanical assemblies, and laboratory equipment, collaborating closely with design, test, and cross-functional engineering teams. The work involves frequent interaction with CAD workstations, test labs, and fabrication or assembly areas to bring mechanical designs from concept to reality. The environment supports rapid iteration and experimentation, offering the opportunity to contribute directly to the growth and scaling of advanced battery technology within a fast-paced and collaborative culture.

This is a Contract position based out of Berkeley, CA.

The pay range for this position is $60.00 - $70.00/hr.

Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to specific elections, plan, or program terms. If eligible, the benefits available for this temporary role may include the following: • Medical, dental & vision • Critical Illness, Accident, and Hospital • 401(k) Retirement Plan – Pre-tax and Roth post-tax contributions available • Life Insurance (Voluntary Life & AD&D for the employee and dependents) • Short and long-term disability • Health Spending Account (HSA) • Transportation benefits • Employee Assistance Program • Time Off/Leave (PTO, Vacation or Sick Leave)

This is a fully onsite position in Berkeley,CA.

This position is anticipated to close on Aug 27, 2026.

About Actalent

Actalent is a global leader in engineering and sciences services and talent solutions. We help visionary companies advance their engineering and science initiatives through access to specialized experts who drive scale, innovation and speed to market. With a network of almost 20,000 consultants and 5,000 clients across the U.S., Canada, Asia and Europe, Actalent serves many of the Fortune 500. We are proud to be an Engineering News-Record (ENR) Top 500 Design Firm for our engineering design services and a ClearlyRated Best of Staffing® winner for both client and talent service.

The company is an equal opportunity employer and will consider all applications without regard to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

If you would like to request a reasonable accommodation, such as the modification or adjustment of the job application process or interviewing process due to a disability, please email actalentaccommodation@actalentservices.com for other accommodation options.

San Francisco Fair Chance Ordinance: Pursuant to the San Francisco Fair Chance Ordinance, for all positions located in the city and county of San Francisco, we will consider for employment qualified applicants with arrest and conviction records.

Massachusetts Lie Detector: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Use of Artificial Intelligence (AI): We may use Artificial Intelligence (AI) to support parts of our hiring process, including sourcing, screening, and evaluating candidates. AI helps assess applications and qualifications, but final decisions are made by our hiring team. By applying, you acknowledge and agree that your application may be reviewed using AI tools.