We now have a comprehensive user’s manual for the BMSs! Click here to download the manual (PDF)
BMS For 8 cell, 24v volt Lithium-iron-phosphate DIY batteries.
100 amp continuous charge or discharge current.
Low Temperature Charging cutoff at -1c.
The Apps allow you to monitor SOC (state of charge), Current, Voltage, cell balance, temperature, and more.
This unit has a connection for a remote shutoff switch. Useful for storage or security.
Bluetooth Module is included, Balance wires are included, USB module is an additional purchase.
Example of a complete 8 cell battery with BMS:
To view or change Parameters, there are 3 ways to connect to the BMS.
1. Bluetooth module to IOS app. The app is on the Apple app store, it is free to view operational data, but costs $6 to view and change parameters.
2. Bluetooth module to Android app.
3. USB module to PC/desktop application. This application is free
IOS app is on the Apple app store. Search for “xiaoxiangBMS”
See the support forum at Reddit.com/r/OverkillSolarBMS for more help and discussions.
A great resource for general DIY power education is www.Mobile-Solarpower.com
FYI for experimenters: The BMS communicates with a 5v TTL UART at 9600 baud. It is directly compatible with Arduinos, etc.
The protocol is similar to MODBUS. requests and responses are in HEX. Protocol datasheet is available on the github page.