Mainspring Energy

Staff Mechanical Engineer - Battery Design

Menlo Park, CA · Staff+

Sponsorship not specified$172k-$203kDetected 33 days ago

Supply ChainSolidWorksFEAThermal AnalysisEMI/EMCMechanical DesignElectrical EngineeringPower ElectronicsLeadershipCollaboration

About the role

Provide technical leadership on complex battery-related challenges.
As Mainspring's internal battery technical authority, you will help define next-generation battery architectures for future products while improving systems already in production.
You'll influence key decisions across cell integration, thermal management, safety, and system architecture while working at the intersection of mechanical, electrical, and battery engineering.

Serve as Mainspring's technical lead for battery pack and module design.
Partner with battery suppliers to review, improve, and influence pack and module architectures.
Own battery hardware from requirements definition through production launch and sustaining engineering.
Evaluate battery designs for safety, reliability, manufacturability, thermal performance, lifecycle, and cost.
Lead technical reviews of cell integration, interconnect systems, thermal solutions, and safety features.
Support supplier selection, design reviews, validation activities, and manufacturing readiness.
Develop battery architectures for future generator platforms.
Collaborate with Electrical Engineering, BMS, Reliability, Manufacturing, Test, NPI, and Supply Chain teams.
Lead root-cause investigations and corrective actions for production, test, and field issues.
Travel to supplier sites as needed to support development and issue resolution.

10+ years of engineering experience with significant focus on lithium-ion battery pack or module design.
Experience working directly with battery suppliers and contract manufacturers.
Experience designing series and parallel battery architectures.
Working knowledge of cell construction, dielectrics, fusing, compression systems, and thermal interface materials.
Experience with battery thermal management and thermal runaway propagation mitigation.
Knowledge of environmental durability, vibration, grounding, creepage/clearance, and EMI-related packaging requirements.
Experience supporting validation testing, manufacturing launch, and sustaining engineering.
Experience with UL certification of battery systems.
Proficiency with SolidWorks and PLM systems.
BS or MS in Mechanical Engineering or a related discipline.
Deep understanding of battery pack and module architecture.
Strong knowledge of cell integration and interconnect design, including bus bars, current collectors, voltage sensing, harnessing, and cell terminal joining methods.
Understanding of battery aging, lifecycle performance, and charge/discharge behavior.

Experience with prismatic-cell battery systems.
Knowledge of BMS integration, contactors, relays, and protection systems.
Experience with high-voltage battery or power systems.
Experience with battery thermal protection materials and thermal interface design.
Familiarity with FEA tools such as Ansys.
Experience with products deployed in harsh outdoor environments.
Background in EVs, energy storage systems, industrial electrification, power electronics, or other ruggedized energy platforms.
Does your experience not meet all of our posted requirements?

This compensation and benefits information is based on Mainspring Energy's estimate as of the date of publication and may be modified in the future.

This listing is sourced directly from Mainspring Energy's careers page and normalized into a canonical job model.