Hi all, I have a battery labeled 48v20ah from a supersoco. I am using it with a phaserunner controller with brushless hub motor.
So I've taken the top off of the case and drilled a hole, spliced my connections and closed it back up. I can charge with the original connection as well as having a universal lead.
Under just 5 Amp load, voltage is dropping to 18v! I guess there's communication with the controller via the 4 smaller pins on the connector. Labeled S1,2,3,4
Has anyone done something similar and know what could be done? Otherwise I'll throw another bms in. But I'll test the battery without bms first.
Thanks
Is the battery fully charged?
Where are you measuring the 18V?
If possible I would try and measure the voltage at the main battery terminals (so inside the battery) as this will tell you if the battery is failing or the stock BMS is cutting the voltage. It kind of sounds to me like the battery cells are failing under load.
@petesscalefabshop thanks for such a quick response
I did exactly what you suggested under the suspicion of faulty cells. I doubted cells are bad because the battery case and button even the port look new.
Its fine. Pulled 40 amps off it last night with with no BMS involved. So its gotta be the BMS either detecting wrong voltage, or Its possible theres a e lock involved as way to prevent use with no SOCO controllers. Because I don't have a explanation for those 4 wires.
I can hear the BMS is on due to the high pitch whining. The 4 wires are black, red, blue, green, they are connections on the charger too. So it's some sort of communication I'm sure.
Do you know what the wires are ? I could put a new bms but the balance leads are ribbon cable. I'd rather use this if can get it to work lol.
Peace
Certainly on the TC Max battery the 4 small wires are for the can bus comms to the instruments, I believe that they also allow the BMS to shut off the stock charger when the battery is charged, although I have no evidence to support this.
I guess it's possible that the controller also talks to the battery.
Sounds as if you might have to either run the bypass full time and just use the BMS for charging or as you say replace the BMS entirely.
