Battery Interface Module (BIM), and its predecessor Battery Monitor Module (BMM), were a series of lithium-ion battery management system designs created by ABK Engineering’s founder, Aaron Bonnell-Kangas.

The modules were built for Buckeye Current, a student-led design/build team at Ohio State University that built electric road-racing motorcyles for professional competition. BMM and BIM perform many critical monitoring and maintenance functions for a high-voltage battery pack in a race vehicle:

• Isolated cell voltage monitoring for strings of 12-36 lithium cells (50-150V) per module
• Scalable to larger battery packs (450+V) with multiple modules coordinated by a central controller
• Onboard control processor for signal processing and battery balancing logic
• Isolated CAN interface and wide-input-voltage power supply to integrate with vehicle networks
• Onboard resistive cell balancing
• Temperature measurement (PCB and external sensors for cell temperature)

Design documentation for the Battery Interface Module is online as an open-source reference.

BMM and BIM are not available as commercial products, but ABK Engineering is ready to help consult on your existing BMS design or work with you to develop a new one. Our experience with 600V electric powertrains and our broad integration capabilities make us a great fit for teams working to develop mules, prototype builds, motorsports vehicles, and other low-volume applications with unusual requirements. If that sounds like what you’re working on, reach out to us and see how we can help.