At WHOOP, we're on a mission to unlock and inspire performance for life. WHOOP empowers members to perform at a higher level through a deeper understanding of their bodies and daily lives. WHOOP is hiring a Senior Battery Systems Engineer to lead the architecture, integration, and validation of battery systems for current and next-generation wearable products. You will work at the intersection of cell chemistry, battery pack architecture, electrical engineering, mechanical design, firmware, manufacturing, quality, and supply chain to deliver safe, reliable, and high-performing battery solutions. Through hands-on experimentation, rigorous data analysis, and cross-functional technical leadership, you will advance battery technology and strengthen engineering standards across the complete product development lifecycle. RESPONSIBILITIES: - Own battery subsystem architecture, requirements, integration, and validation from early concept development through new product introduction, mass production, and sustaining engineering. - Partner with Product, Battery Cell Engineering, Electrical Engineering, Mechanical Engineering, Firmware, and other cross-functional teams to translate product goals into battery requirements, energy and power budgets, consumption profiles, verification plans, and design documentation. - Lead the integration of charging systems, fuel gauging, protection circuitry, thermal sensing, firmware controls, telemetry, system power architecture, and mechanical battery design to optimize performance, safety, reliability, and member experience. - Develop and execute comprehensive design verification and qualification strategies, including design of experiments, accelerated life testing, reliability assessments, DFMEAs, design reviews, and pack- and system-level testing. - Lead structured root-cause investigations for development, manufacturing, and field issues, using test data, field telemetry, failure trends, and analytical tools to drive objective engineering decisions and continuous product improvement. - Partner with Quality, Manufacturing, Supply Chain, external suppliers, and third-party laboratories to evaluate specifications, qualify designs and processes, establish manufacturing controls, support regulatory compliance, and assess emerging battery technologies; travel up to 15% to engage with suppliers, manufacturing partners, and testing facilities. QUALIFICATIONS: - Bachelor’s degree in Electrical Engineering, Mechanical Engineering, Chemical Engineering, Materials Science, Electrochemistry, or a related technical field, with 4+ years of relevant experience; an advanced degree with 2+ years of relevant experience will also be considered. - Strong understanding of lithium-ion cell chemistry, electrochemistry, battery pack behavior, degradation mechanisms, and the relationships among electrical, mechanical, thermal, and firmware systems. - Hands-on experience developing and executing test protocols for battery packs, electrical systems, printed circuit boards, or integrated hardware products. - Working knowledge of charging circuits, battery protection, fuel gauging, thermal management, battery management systems, and embedded firmware controls. - Experience using design of experiments, statistical analysis, accelerated life testing, reliability engineering, and structured failure-analysis methods to solve complex technical problems. - Ability to interpret electrical schematics, mechanical CAD models, tolerance analyses, engineering drawings, and GD&T callouts. - Strong cross-functional leadership and technical communication skills, with the ability to navigate ambiguity, articulate engineering risks and trade-offs, and collaborate effectively with internal teams and external partners; experience with space-constrained consumer electronics or high-volume battery manufacturing is preferred. - Strong commitment to embracing and leveraging AI tools in day-to-day tasks, ensuring AI-assisted work aligns with the same high-quality standards as personal contributions. This role is based in the WHOOP office located in Boston, MA. The successful candidate must be prepared to relocate if necessary to work out of the Boston, MA office. Interested in the role, but don’t meet every qualification? We encourage you to still apply! At WHOOP, we believe there is much more to a candidate than what is written on paper, and we value character as much as experience. As we continue to build a diverse and inclusive environment, we encourage anyone who is interested in this role to apply. WHOOP is an Equal Opportunity Employer and participates in E-verify https://www.e-verify.gov/ to determine employment eligibility. 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. The WHOOP compensation philosophy is designed to attract, motivate, and retain exceptional talent by offering competitive base salaries, meaningful equity, and consistent pay practices that reflect our mission and core values. At WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company’s long-term growth and success. The U.S. base salary range for this full-time position is $140,000 - $195,000. Salary ranges are determined by role, level, and location. Within each range, individual pay is based on factors such as job-related skills, experience, performance, and relevant education or training. In addition to the base salary, the successful candidate will also receive benefits and a generous equity package.