Cowboy Space is a startup building orbital data-center satellites and an in-house rocket program to launch them.
The Role We're looking for a Battery Engineer to own the design, development, integration, and qualification of our spacecraft battery systems. You'll be responsible for developing reliable, high-performance energy storage solutions that power the spacecraft through eclipse periods, peak load events, and critical mission operations. This is a hands-on individual contributor role for an engineer who enjoys taking battery systems from concept through flight. You'll work closely with power electronics, avionics, thermal, mechanical, and software engineers to develop flight-ready battery hardware capable of operating safely and reliably in the harsh environment of space. Responsibilities - Own the architecture and development of spacecraft batteries from concept through flight qualification - Design battery packs, module architectures, and electrical interconnects (e.g., laser welding, wire bonding, busbar design) to meet mission performance requirements, including series/parallel cell configuration trade-offs - Develop a battery management system (BMS), including cell balancing (passive and active balancing techniques), state-of-charge (SOC) and state-of-health (SOH) estimation (coulomb counting, OCV-based, and model-based/Kalman filtering approaches), fault detection, and protection strategies (overvoltage, undervoltage, overcurrent, overtemperature, cell imbalance) - Select battery cell chemistries and components (e.g., NMC, NCA, LFP, or primary Li-CFx for long-duration/low-power missions) based on mission requirements, specific energy/power trade-offs, cycle life, reliability, and environmental constraints - Perform battery sizing, capacity analysis, degradation modeling (capacity fade, impedance growth), depth-of-discharge (DoD) management for cycle life targets, and lifecycle assessments - Develop battery charging and discharge strategies in partnership with the spacecraft power systems team, including coordination with solar array power management (MPPT vs. direct energy transfer) and peak-load discharge current limiting - Define thermal management requirements and collaborate with thermal engineers to ensure safe battery operation, including thermal runaway propagation mitigation (cell-to-cell spacing, thermal barriers, venting design) and cold-survival heater strategy - Lead battery integration, validation, environmental qualification, and acceptance testing, including vibration/shock (per GEVS/NASA-STD-7001 or ECSS equivalents), thermal vacuum cycling (TVAC), vacuum outgassing (ASTM E595), and abuse testing (overcharge, short circuit, crush, penetration, thermal abuse) - Investigate battery performance, reliability, and failure modes through analysis and testing, including root-cause failure analysis and corrective action development - Support manufacturing, supplier selection, DFM/DFT reviews, cell matching/sorting processes, weld quality inspection (including X-ray/CT inspection for internal defects), and production readiness - Support spacecraft integration, launch campaigns, and on-orbit battery performance monitoring and trending Basic Qualifications - BS, MS, or PhD in Electrical Engineering, Mechanical Engineering, Materials Science, Chemical Engineering, or a related discipline - 3+ years developing battery systems for aerospace, automotive, defense, or other high-reliability applications - Experience designing battery packs and energy storage systems, including cell/module/pack architecture and electrical interconnect design - Knowledge of lithium-ion battery chemistry (NMC, NCA, LFP), degradation mechanisms, and safety considerations - Experience developing or integrating Battery Management Systems (BMS), including cell balancing, SOC/SOH estimation, and fault protection architectures - Experience with battery testing, characterization, and validation, including cycle life testing, performance characterization across temperature, and abuse/safety testing - Familiarity with battery modeling (equivalent circuit models or electrochemical models), lifecycle analysis, and performance prediction - Strong analytical and hands-on hardware debugging skills Preferred Qualifications - Experience developing spacecraft or satellite battery systems - Experience with radiation effects on battery systems and space-qualified components - Experience with battery thermal modeling and thermal runaway mitigation, including coupled thermal-electrochemical simulation (e.g., COMSOL) - Knowledge of NASA, ECSS, or aerospace battery qualification and safety standards (e.g., MSFC-STD-3012 lithium-ion battery safety guidelines, AFSPCMAN 91-710 range safety requirements, GEVS/NASA-STD-7001 environmental verification, ECSS-E-ST-20-01) - Experience supporting vibration, shock, thermal vacuum, and environmental testing campaigns - Experience with battery safety analysis including FMEA, fault tree analysis (FTA), and hazard assessments, along with familiarity with abuse/safety test standards (UN 38.3, IEC 62133, UL 1642/2054) - Familiarity with MATLAB/Simulink, Python, or equivalent tools for battery modeling, SOC/SOH algorithm development, and analysis - Experience with isolated cell monitoring architectures and BMS IC platforms (e.g., isoSPI daisy-chain architectures common in EV/aerospace battery stacks) - Experience supporting battery hardware from prototype through flight, including launch campaign support and on-orbit anomaly investigation Compensation and Benefits The salary range for this position is $167,000 - $230,000 annually. The actual base salary offered will depend on factors such as job-related skills, experience, qualifications, and internal equity. - Equity in Cowboy Space Corp. - Employees and their eligible dependents may enroll in medical, dental, and vision insurance - 401(k) retirement savings plan - Paid time off - 10 paid holidays per calendar year - Paid parental leave - Relocation assistance