Replacement or repair of Haibike Yamaha BMS?

[Jobe]

My wife somehow fried the charging port on her Haibike w/Yamaha motor and battery. I hardwired a new charger to the battery after opening the pack and carefully insuring correct wiring (I am an Electrical Engineer) as connector was fried useless. Plan was that once I verified battery would charge, I would replace the connector with a similar plug/socket combo as original connectors are not readily available in the US. That done, battery would not show it was charging. I suspect component failure in the Yamaha BMS board inside the battery case perhaps due to reverse polarity when she plugged charger to battery incorrectly? (Which doesn't say much for the Haibike mechanical design which should have prevented this). Incidentally the battery did run motor fine with what charge was left in it, just that now it can't be charged. Does anyone know if or where I could get a new or used Yamaha BMS board?

 

[Rory166]

You cannot buy a replacement yamaha bms. Even re-celling the pack bricks the bms. As the bike worked for the remaining charge would it work if you charged the cells directly? A number of people on German Pdelec forum are working on a reverse engineered system which will enable a battery to run the Yamaha motor system. This requires a serial data terminal to send charge state info continuously. They are using an arduino and a cheap chinese bms.