Firmware Engineer, Battery Systems

About the role: As Firmware Engineer, you are responsible for all the key functions of a battery system (monitoring, protection, communications, etc). You create algorithms for estimating state of charge, define all the states and transitions of the battery, implement all communication protocols, and ensure reliable protection functions.

Why this role matters: The operating performance and safety of the battery pack rely on firmware that is well designed and thoroughly validated. From critical timing control of interrupts to carefully configured peripherals to minimize power consumption, to innovative SOC estimation algorithms, every aspect of the battery pack’s performance relies on firmware.

What you'll do:

• Create a firmware platform for the battery pack with bare metal/RTOS and drivers
• Define pinouts of microcontrollers to ensure proper allocation of peripherals
• Design protection functions with redundancy and consistent timing
• Power sequencing and pre-charge control for inrush current limiting
• Design SOC/SOH estimation algorithm for our unique solid-state batteries
• Define states and transitions to cover all operating modes
• Ensure minimum operating and sleep mode power consumption
• Create a scheme for firmware read/write protections and upgrade
• Collaborate with ODM partners to create and validate firmware protocols
• Bring up hardware platforms that are built from scratch by identifying issues and working with hardware engineers to resolve them
• Provide firmware validation and regression test plans to our lab

What you bring:

• 5+ years writing BMS firmware for lithium-Ion battery packs
• Proficiency with TI C2000, STM32 or similar microcontroller platforms
• In-depth understanding of timing and latency control of RTOS and Interrupts
• Experienced in designing and fine-tuning SOC/SOH estimation algorithms
• Familiar with configuring hardware peripherals (ADC, PWM, Comparator, UART, etc) and writing drivers
• Capable of creating a firmware platform from scratch
• Comfortable with working on medium to high power battery packs (>20kW)
• Good understanding of battery protection features and safety requirements such as UL2054, UL1973, UL 9540A and IEC 62133
• Experience implementing battery/power management communication protocols such as SMBus, PMBus and ModBus
• Track record with at least two battery products through prototype bring up, validation and regulatory approval
• Fluent in C for bare-metal and RTOS environments; comfortable with fixed-point math for real-time control

Nice to have:

• Experience in digital control of power converters (PFC, DC/DC, Inverters, etc)
• Good understanding of Lithium-Ion battery chemistry and characteristics
• Familiarity with OpenBMC integration and Redfish/IPMI protocols
• Experience with code review and audits for regulatory compliance
• Experience with configurable modular multi-pack systems
• Exposure to OCP power shelf communication and management standards
• Experience in a customer facing application engineering role

ONSITE: This position is required to work onsite 5 days per week to meet the minimum essential duties and requirements of this position. As an on-site R&D and manufacturing operations organization, in-person face to face interaction is essential to building authentic relationships, trust, teamwork, and collaboration.