Today I found the time to solder the final components to the monitor boards and ESP32 controller board.
After fireing up the board I was surprised by the easynes of use of the interface and the way it looks. My compliments it looks and works great.
During my first test and soldering the boards I found a few issues that might need some attention.
- the airgaps for K1 and K2 are a bit small for example the gaps on the side of the common track should go all the way up to the end of the track. The way it is now does not cover the space in between the coil pins and the common track. Also on some other points the tracks for the coils are dangerously close to the switching tracks of K1 and K2. This is a safety issue.
- the emergency off J1 connection triggers emergency by connecting the pins. A regular emergency switch is disconnecting to pins instead of connection. Also a emergency device that is connected to J1 will not trigger emergency if it gets disconnected. I think it is safer to reconfigure J1 that it triggers emergency the moment the two pins are disconnected from each other.
- I’m missing security on entering the BMS web interface that can lead to unwanted change of settings by people with wrong intentions.
- finally nntp time setting does not respond to timezone hour change and daylight saving changes.
But despite my comments above I think this is a great project I could load firmware to all my 50 monitor modules from the controller board super fast, connecting 20 of them with all only 1 18650 cell on it worked without a problem and it nicely could balance the cells that all had a random SOC.
The upcoming days I will dive in what is being published via MQTT to see if I can get that stored in a DB and create a dashboard with it.