Position: Battery Management System (BMS) Engineer
Location: Tokyo (Midtown area) & lab facilities within the Kanto region
Employment Type: Full-time
Remote Work Allowance: Available
Trial Period: 3 months

Job Overview
We are looking for a skilled and innovative Battery Management System (BMS) Engineer. The successful candidate will play a key role in the design, development, and optimization of battery management systems to ensure the safety, efficiency, and longevity of advanced battery packs.

Key Responsibilities

Design and develop hardware and firmware components for BMS tailored to lithium-ion or next-generation battery technologies
Implement algorithms for State of Charge (SOC), State of Health (SOH), and State of Function (SOF) estimation to optimize battery performance and lifespan
Collaborate closely with cross-functional teams (electrical, mechanical, software engineers)
Integrate BMS into overall system architecture
Conduct simulations, modeling, and testing under various operational conditions (e.g., temperature, load, failure scenarios)
Develop safety mechanisms including overcharge/discharge protection, thermal management, and fault detection
Analyze and interpret battery data to improve system efficiency and reliability
Ensure compliance with industry standards and regulations (e.g., ISO 26262, UL, IEC)
Support prototype building, testing, and validation (both in lab and field settings)
Document designs, testing results, and processes for internal use and regulatory submissions
Stay up to date with trends in battery technology, BMS methodologies, and emerging industry developments

Tools Used

Google Workspace (Gmail, Calendar, Meet, etc.)
Slack
Notion
Dialpad
SmartHR
Money Forward
Bakuraku

Requirements
Must-Have Skills:

Bachelor’s degree in Electrical Engineering, Computer Engineering, Mechanical Engineering, or related field (Master’s preferred)
5+ years of experience in BMS design, development, or testing
Proficiency in embedded systems programming (C/C++) for microcontrollers or DSPs
Deep understanding of battery chemistry (e.g., Li-ion, LiFePO4) and related electrical properties
Experience with communication protocols (e.g., CAN, I2C, SPI, UART)
Knowledge of circuit design, PCB layout, and power electronics related to BMS hardware
Proficiency in simulation tools (e.g., MATLAB/Simulink, LTspice)
Hands-on experience with lab equipment (e.g., oscilloscopes, multimeters, battery cyclers)
Understanding of thermal management principles and safety standards for energy storage systems

Nice-to-Have Skills:

Experience with automotive BMS applications and functional safety compliance (ISO 26262)
Knowledge of machine learning techniques for predictive battery analytics
Hands-on experience with high-voltage systems (400V+) and related safety protocols
Understanding of cloud-based battery monitoring or IoT integration

Candidate Profile

Proactive in tackling new challenges and complex problems
Skilled at coordinating across internal and external stakeholders
Adaptable and enthusiastic about change
Self-motivated and action-oriented
Strong written and verbal communication skills
Willingness to learn new areas independently
Able to work on-site daily

Work Style

Monthly scheduled work: 8 hours/day × working days in the month
Flextime system (core hours: 11:00–15:00; 60-minute break)
On-site attendance required
Occasional business trips expected

Time Off

Weekends and public holidays
Year-end and New Year holidays
Paid leave: 12 days in the first year (5 days upon joining, remaining 7 after 6 months)
Other special leaves (e.g., bereavement)

Benefits

Full social insurance coverage (employment, work injury, health, pension)
Employee stock ownership plan (with incentives)

Additional Notes

English is used as the working language; an English CV is required upon application
Candidates looking to improve their English are also welcome

BMS System Engineer