Why Open Battery Information?
Manufacturers often lock the BMS when a fault is detected. When that protection triggers falsely or the fault is repairable, the pack can be saved instead of thrown away.
Unlock dead batteries
Read status, charge cycles, and error codes from battery packs whose BMS has locked them out.
Web Serial, no drivers
Talks to your Arduino over the Web Serial API. No drivers, no cables beyond USB, no installs.
Private by design
Everything runs locally in your browser tab. No accounts, no telemetry, no data leaves your machine.
How it works
Build a small interface, then read your pack in three steps.
Set up the hardware
Build the Arduino OBI interface and wire it to your battery, following the wiring guide.
Connect the board
Open OBI-1, pick your Arduino, and press Connect. The board resets and identifies itself automatically.
Read the battery
Insert a battery, press Read battery, and see cell voltages, temperatures, charge cycles, and status at a glance.