lmwilco1
New Member
2.85 seems pretty low for the battery voltage under load. How much power are you pulling out of the cell?
Thanks very much for the reminder. I knew that but sadly was getting ready to miss it...I would charge the one cell to 3.5 and then connect all cells in parallel for at least a day before testing again.
If you get one cell out of balance and try charging with hi and low cells in the pack, the whole pack will charge to a target voltage...The cells with the lower voltage will cause the whole pack voltage to be lower and the cells with the higher voltage will spike up a ton and will bloat.....
<<<<DO NOT CHARGE A CELL in a PACK IF ANY OF THE CELLS ARE NOT ALL BALANCED>>>>
I know from experience.....very sad....
I connected my charge resister to the terminals on either side of my main circuit breaker/switch/disconnect.Re my concerns on the BMS wiring. The issues are more around tying the MPP Hybrid Inverter and BMS together. Adding rings to the BMS wires and connecting to the battery that is arranged/wired in series seems straightforward. Looking at Will's picture of the handcart system:
The main negative feeds directly to the Hybrid Inverter (HI) and the main positive feeds to the HI via a shunt, then a circuit breaker. The BMS is wired into the shunt and also wired into the HI switch. Is there an easier way to wire the BMS as opposed to directly to the HI switch
I was advised to include "a pre charge resister to charge the capacitors in the inverter, if you don't it will likely put your BMS into over current shutdown mode." Where exactly does that go in this setup?
Looking at the Detailed Assembly instructions for the Overkill BMS, the dual heavy gauge wires C- are bolted to the frame for a negative chassis ground system. Given I am doing the hand cart system, do I still do it this way?
Gotta say ... this thread is great. I will be referencing it often as I work through my project when things get here.
I agree...I have screwed things up and we all make mistakes. I just don't want people to make the same mistakes I have.....I agree. I have been very fortunate to have several posters be patient and try to walk me through this process...
Instead I'm building my battery inside an ice chest.
I am north of 50 years old and have been playing with batteries and electronics off and on since I was a teen ager, and I had to recently re-learn how to make connectors for high amperage applications.