Battery Engineering Specialist

About the role

You will join the battery engineering team of a company building products around lithium-ion cells, from modules and packs to full energy storage systems. The team owns cell selection, characterization, and validation: every cell that ships in a product passed through your test plans first. This role matters because cell performance, safety, and lifetime define product warranties and field reliability, and your test data is the evidence behind every claim the company makes. You will go deeper on cell behavior than anyone else on the team, from degradation mechanisms like SEI growth and lithium plating to the thermal runaway propagation testing that underpins safety cases. The role includes qualifying new cell suppliers through teardown analysis, cycle-life test oversight, and factory audits. Your specifications for SOC windows, C-rates, and thermal limits will directly set warranty terms and bankability opinions. You will also monitor the fast-moving cell technology landscape, from LFP refinements to sodium-ion and solid-state claims, advising leadership on what is ready for deployment and what is still lab news.

What you will achieve

• Qualify new cell suppliers 30 percent faster through standardized test matrices covering capacity, rate capability, cycle life, and calendar aging
• Build cell-level models (ECM and physics-informed) that predict pack performance within 3 percent across temperature and SOC windows, with test plans designed to discriminate between supplier performance claims
• Own abuse and safety test campaigns per UL 1642, UL 2580, and UN 38.3, closing findings with suppliers before design lock
• Cut field failure rates by driving root-cause analysis on returned cells, from teardown and CT imaging through corrective action, tied explicitly to warranty thresholds and augmentation triggers
• Deliver cell selection recommendations backed by total-cost-of-ownership models spanning energy density, cycle life, and warranty risk

What you will bring

Must-haves

• 2 to 5 years of hands-on experience with lithium-ion cell testing, characterization, or applications engineering
• Deep understanding of cell electrochemistry: NMC, LFP, and emerging chemistries, plus degradation modes (SEI growth, lithium plating, particle cracking)
• Proficiency operating battery cyclers and designing test profiles: HPPC, rate tests, cycle life, and calendar aging
• Data analysis skills in Python or MATLAB for large time-series datasets from long-duration testing
• Working knowledge of cell safety standards: UL 1642, UL 2580, IEC 62133, and UN 38.3 transport testing
• Ability to read and challenge supplier datasheets, translating spec-sheet claims into validated performance
• Clear technical reporting that turns thousands of cycles of data into go/no-go decisions

Nice-to-haves

• Experience with EIS, incremental capacity analysis, or differential voltage analysis techniques
• Familiarity with BMS algorithms: SOC/SOH estimation, cell balancing, and thermal management
• Exposure to solid-state or sodium-ion cell evaluation
• Knowledge of pack design constraints: busbar sizing, thermal interface materials, and enclosure requirements
• Experience with battery management system algorithms and state-of-charge estimation