Battery System Engineer

Job description

About ALSO. We’re ALSO, an electric mobility company originally conceived as a part of Rivian. We’re a passionate team of builders, dreamers, doers and innovators, focused on creating entirely new (not to mention, innovative and delightful) vertically integrated, small EVs designed to meet the global mobility challenges of today and tomorrow. Our mission is to inspire everyone to ride ALSO—replacing many local car, truck and SUV miles with ones on vehicles that are more affordable, more enjoyable and 10-50x more efficient. We're looking for a Battery Systems Engineer (at all levels) to own the battery system architecture and analytical foundation behind our battery systems, helping define not just the battery pack but the broader energy strategy and operating philosophy of the vehicle platform. You'll drive key technical decisions across cell selection, charging strategy, pack architecture, thermal behavior, controls integration, performance, degradation, and operating strategy, directly shaping product direction, vehicle capability, user experience, range, cycle life, cost, and the platform's long-term energy strategy. This is a highly cross-functional systems role spanning battery engineering, vehicle architecture, controls, thermal systems, and product definition. You should be equally comfortable building models, defining operating concepts, debating architecture tradeoffs, and helping teams converge on the right technical decisions. What You'll Do - Own the analytical foundation behind the battery system, leading trade studies across chemistry, pack topology, SOC window, cell selection, and operating limits, and translating engineering decisions into cost, range, performance, and cycle life tradeoffs that drive product and business direction - Build and advance cell- and pack-level electrical, thermal, and degradation models, developing battery duty cycles from real-world usage data and mission profiles, correlating models against measured data, and using them to set architecture decisions, design targets, and operating limits - Define how the battery operates, including charging strategy, operational use cases, user-facing behavior, degradation management, and end-of-life operating strategy, ensuring these are reflected in system requirements, controls logic, and vehicle integration - Own cell evaluation and down-selection, defining characterization test plans, interpreting performance and degradation data, and translating cell behavior into pack-level model inputs, design constraints, and BMS operating envelopes - Define battery system requirements including protection thresholds, thermal limits, charge/discharge constraints, contactor and fuse sizing, fault detection, and end-of-life criteria, partnering with BMS hardware, firmware, and controls teams to bring the use case context and cell behavior constraints they need to succeed - Close the loop between analysis and hardware by defining test cases, supporting bench and vehicle-level bring-up, and driving model-to-measurement correlation across electrical, thermal, and degradation domains - As an early member of a growing battery engineering team, your rigor, speed, and standards will set the bar for the engineers who come after you What You'll Bring - 8+ years in battery systems engineering with demonstrated ownership of battery architecture and requirements on a shipped product, not program support or analysis in isolation - Deep understanding of lithium-ion cell behavior, including electrochemical operating principles, thermal characteristics, degradation mechanisms, and how these translate into real-world duty cycle and pack design constraints - Hands-on modeling expertise (Python, MATLAB, Simulink) building equivalent circuit models, thermal networks, degradation behavior, and pack-level simulation from scratch, not just running them - Experience developing or validating duty cycles for EV or electrified powertrain applications and translating mission profiles into battery requirements and operating limits - Proven ability to translate cell and pack behavior into BMS hardware and firmware requirements, including protection thresholds, contactor and fuse sizing, parallel cell current balance, and fault detection logic, working directly with embedded teams - Fluent enough in controls and embedded systems to be technically credible and drive alignment at BMS and controls design reviews - BS/MS in Electrical Engineering, Mechanical Engineering, or related field - Bonus: Cell characterization experience (HPPC, OCV curves, degradation cycling) and familiarity with BMS state estimation algorithms (SOC, SOH, SOE) and how they interface with controls - Bonus: Experience with advanced simulation tools (Ansys Mechanical, Fluent, Icepak, or equivalent) and fast-charge protocol development and optimization - Bonus: Background in small EVs, two-wheelers, or light electric mobility platforms, familiarity with requirements management tools, and strong business acumen in framing engineering tradeoffs around cost, program risk, and product impact The salary for this position ranges from $150,000 - $255,000 per year, depending on experience, qualifications, and location. Perks & Benefits - Robust health coverage — excellent health, dental and vision insurance covered up to 100% by ALSO with FSA & HSA options - One Medical membership and dedicated insurance advocates - Rich fertility and family building benefits with Progyny - Flexible time off - 401(k) match Why ALSO. We’re passionate about helping the world find a better way to get there—wherever it is you’re headed. We’re located in the heart of Silicon Valley and have brought together a world-class team from some of the biggest brands in the technology, automotive, cycling, outdoor recreation and retail spaces. Together we’re working hands-on to imagine, design and build an entirely new solution to a global set of transportation challenges.