The foxBMS 1 version 1.5.2 is available on GitHub.

We publish major software releases for our open source BMS platform every 3 to 6 months and interim bug fixes when solved in the News section. By subscribing to the foxBMS Newsletter, you will be informed when the new releases are available. Further, the foxBMS Roadmap and the Documentation are also updated regularly.

Warning: The foxBMS platform including the foxBMS hardware and the foxBMS software are under permanent development. The free and open research and development platform foxBMS as presented in the documentation hereafter is not provided to be used without any adaptions (e.g., to fulfill mandatory regulations) in consumer products, electric vehicles, production environments or any similar usages: it is only intended to be used by skilled professionals trained in designing battery system prototypes.

Based on all the feedback received during the last 2 years from foxBMS software partners and users, the embedded software and the computer software have been restructured to reduce the MCU hardware dependency and enable even more flexibility.

Hereafter is a summary of the changes provided in foxBMS 1 version 1.5.2.


  • Toolchain:
    • updated to “waf-2.0.12“ (from “waf-2.0.11“)
  • Bugfixes:
    • fixed bug that delay after SPI wake-up byte was not long enough
  • Enhancements:
    • increased CPU clock frequency from 168MHz to 180MHz
    • increased SPI bitrate from 656.25kHz to 703.125kHz
    • Added CAN boot message with SW-version and flash checksum (0x101)
    • CAN messages are now always sent, even if system error was detected
    • foxBMS SW-version requestable via CAN (request ID: 0x777, response ID: 0x101)
    • added insulation error flag to “DATA_BLOCK_ERRORSTATE_s“
    • configurable behavior if contactors should be open on insulation error or not
    • separate configurable precharging for charge/discharge path possible


  • adapted CAN filter circuit on master and extension board for improved fault tolerance at short of CAN_L to GND or CAN_H to supply


  • updated instruction for flashing primary MCU
  • updated FAQ section

In case you encounter problems, please contact us.

The Fraunhofer IISB foxBMS Team