Manufacturing Engineer, Battery

About 1X We’re building humanoid robots that work in home - doing the chores, handling the tasks, and giving people their time back. Simple, but it’s not. To do this right, we have to solve robotics, AI, manufacturing - at the same time, at scale, in a form factor that has to be safe enough to live with your family. If you’re inspired by this, you’ll thrive here. We’ve been at this since 2014 and we’re at the point where the hard problems are behind us and the hard work is in front of us. NEO is our flagship - a home robot designed to move, learn, and operate in the real world alongside real people. We’re not demoing it - we’re shipping it. We’re excited to meet you, if this excites you. If you’ve spent your career working on problems that matter and want to see them actually reach the world - this is that moment. We’re scaling, we’re hiring with intention, and we need people who want to build something that will genuinely change how humans spend their time - safely creating abundance for all. About The Team The Battery team develops the energy storage systems that power NEO. We design and validate battery systems that must deliver high energy density, power, safety, reliability, and long cycle life while operating within the demanding weight, volume, thermal, and packaging constraints of a humanoid robot. Our work spans battery cells, pack architecture, mechanical integration, electrical systems, battery management, thermal management, charging, safety, validation, and manufacturing. We partner closely with Electrical, Mechanical, Controls, Embedded Software, Reliability, Manufacturing, and Supply Chain teams to deliver battery systems that perform safely and consistently in real-world environments. Your Charter Build the battery systems that keep humanoid robots moving. You will own critical elements of NEO’s battery system from architecture and component selection through design, prototyping, characterization, validation, and production. You will develop compact, lightweight, safe, and reliable battery solutions capable of supporting the dynamic power requirements of a humanoid robot operating every day around people. You will work hands-on with cells, modules, packs, test systems, and complete robots, using data from laboratory testing and real-world operation to continuously improve performance, safety, lifetime, and manufacturability. Key Outcomes Design and release production-ready battery systems that meet energy, power, weight, volume, thermal, safety, reliability, cost, and manufacturability requirementsDevelop battery pack architectures integrating cells, busbars, interconnects, sensing, protection, BMS hardware, thermal management, enclosures, and structural interfacesDefine and validate cell and pack performance requirements across charge, discharge, peak power, temperature, aging, and real-world robot duty cyclesImprove battery energy density, power capability, thermal performance, cycle life, reliability, and serviceability through iterative engineering and testingDevelop characterization and validation methods for cells, modules, packs, charging systems, and battery safetyIdentify battery failure modes through testing and data analysis and drive design improvements and corrective actionsSupport battery hardware through prototype builds, design validation, NPI, supplier qualification, and production rampPartner closely with Electrical, Embedded Software, Mechanical, Controls, Reliability, Manufacturing, and Supply Chain teams to deliver fully integrated energy systems Key Competencies Strong engineering fundamentals across battery systems, electrochemistry, electrical systems, thermal management, and hardware developmentAbility to design fixtures and test equipments. Deep understanding of lithium-ion battery behavior, including energy, power, impedance, degradation, thermal performance, and cycle lifeStrong understanding of battery pack architecture, including cells, interconnects, busbars, sensing, protection, thermal systems, and mechanical packagingStrong analytical skills with the ability to use first-principles calculations, battery data, modeling, and physical testing to make engineering decisionsHands-on engineering mindset with the ability to move between system design, cell characterization, pack builds, test equipment, failure analysis, and complete robotsStrong understanding of battery safety, fault conditions, validation, and risk mitigationStrong collaboration and communication skills across electrical, mechanical, embedded software, controls, manufacturing, reliability, and supply chain teams Minimum Requirements Bachelor’s degree in Mechanical Engineering, Electrical Engineering, Chemical Engineering, Materials Science, or a related engineering field5+ years of engineering experience developing battery systems, energy storage systems, or complex electromechanical productsExperience developing fixtures and test equipment. Experience developing lithium-ion battery packs, modules, cells, or related energy storage systemsStrong understanding of lithium-ion cell performance, charging and discharging behavior, degradation, thermal behavior, and safetyExperience with battery pack architecture and integration, including cells, interconnects, sensing, protection, thermal management, and mechanical packagingExperience defining and executing battery characterization and validation testingExperience analyzing battery performance data and using test results to drive engineering decisionsExperience with battery safety, fault analysis, failure modes, and design mitigation strategiesExperience supporting hardware from prototype development through design validation and productionExperience collaborating with electrical, mechanical, embedded software, manufacturing, quality, reliability, and supply chain organizations Preferred Skills Experience developing battery systems for robotics, electric vehicles, consumer electronics, aerospace, drones, or other high-performance mobile productsExperience with cylindrical, pouch, or prismatic lithium-ion cells and cell selection and qualificationExperience with Battery Management Systems (BMS), including cell monitoring, state estimation, protection strategies, and fault handlingExperience with battery thermal management, thermal modeling, cooling strategies, and temperature sensingExperience with high-current electrical design, busbars, connectors, fusing, contactors, and battery protection hardwareExperience developing battery test fixtures, cycler-based characterization, life-cycle testing, abuse testing, or reliability validation systemsExperience with cell aging, cycle-life modeling, State of Charge (SOC), State of Health (SOH), and performance degradation analysisFamiliarity with battery safety and transportation standards such as UL, IEC, and UN 38.3Experience working directly with cell manufacturers, battery suppliers, and contract manufacturing partnersExperience operating in fast-paced hardware environments with rapid design iteration and frequent prototype buildsExperience supporting battery systems through NPI, qualification, reliability testing, and high-volume production ramp What does a successful 1X Team Member look like? Team members at 1X who thrive here are builders. They move fast, own their work completely, and treat time like it’s the one thing you can’t get back - because it is. They say what they mean, finish what they start, and hold themselves to a standard before anyone has to ask. We push each other to be better, and we do it with honesty and respect. Successful engineers on the Battery team are deeply connected to the hardware and the data. They understand that delivering a great battery system requires balancing energy, power, weight, volume, thermal performance, safety, lifetime, manufacturability, cost, and serviceability. They are comfortable moving from battery architecture and first-principles analysis to instrumenting cells, building packs, analyzing cycling data, diagnosing failures, and implementing the next design revision. They work effectively across electrical, mechanical, software, and manufacturing boundaries and take ownership of their systems from initial architecture through a battery powering a robot in the real world. Compensation Range $126,000 - $181,000 + Equity Benefits Comprehensive medical, dental, and vision coverageGenerous paid time off, company holidays, and parental leave401(k) plan with company match (100% on the first 3% of contributions, 50% on the next 2%)Flexible Spending Accounts (FSA) and Health Savings Accounts (HSA) optionsCommuter benefits (transit and parking)Short-term and long-term disability, and life insuranceEmployee Assistance Program (EAP) for mental health, financial, and personal supportOnsite snacks and catered lunches Equal Opportunity Employer 1X is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, gender, gender identity or expression, sexual orientation, national origin, ancestry, citizenship, age, marital status, medical condition, genetic information, disability, military or veteran status, justice system impact, or any other characteristic protected under applicable federal, state, or local law. Compensation Range: $121K - $181K