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Thanks. I will make that change.

Those are for the shore charger that this thread is about. I have now removed the negative from the terminal and connected it to the other side of the BMS.

Thanks so much. I will do that and this makes a lot of sense. The other side of the BMS (black wires) is just connected to a ground on the van body. Are you saying I need to connect somewhere in those wires? Maybe to the same ground?

Very likely I’m using imprecise terms. In the photo, you can see I am connecting the charger to the terminals circled in red and brown. The terminal in brown is connected to the BMS. Is this the proper way to connect this? And it shouldn’t overcharge the battery?

Thank you all for the feedback. I think I am hearing it is safe to leave connected to the main pos and neg for the occasional overnight use since it is so low power. Could I leave it connected for a long time? It may not very quick (which is fine) I just need something very infrequently to help...

Hi all, I searched, I promise and couldn’t fit the info I need. I have a 120ah lifepo4 battery I built from prismatic cells in my van. It charges via a small solar panel permanently mounted and the alternator when I am driving. Recently I haven’t been driving much and my always-on fridge is...

Economical is what I am looking for! How would I test the other three. They are currently all still bound up in a pack and the battery still functions -for safety I disabled the battery this AM. The other three appear fine and voltages read correctly. For some reason (need to diagnose) cell...

I still need to diagnose what I did wrong, but I ruined one of the cells in my 12 v 120 Ah pack (overcharged, vent blown, bad smell). What I did wrong is a different (shameful) discussion. My question is - what do I do with the other three cells? Is it feasible to buy just one cell to replace...

I am getting strange (and wrong) readings from my BMS while the alternator is charging. The BMS reports cell 4 is at a very high voltage (like that 3.8) when the alternator is charging the system. I confirmed with my Fluke voltmeter that the actual actual voltage is closer to 3.5. Readings are...

I calibrated the voltage in the app using my fluke meter. Is that what you are asking? It was surprising close to the readings from my meter out of the box. My Fluke multimeter doesn't measure current, and my other meter is a cheapo big box meter.

Tried to keep the battery setup in my van simple with just the cells, BMS, and electronic bits but am really dissatisfied with monitoring the battery through the bluetooth from the BMS. The SOC seems to be all over the place and a few other annoyances. Can someone point me to a product or...

I’d like to test the voltage of the individual cells in my LIFEPO4 12v pack and compare to the reading of my BMS. Really tired of disassembling the bus bars and balance leads. Will I still get accurate readings for individual cells if I keep them assembled? Assuming no, but wanted to check with...

It is definitely an acquired taste ?‍♂️ Actually I was draining voltage in the hope some of the swelling would go down.

UPDATE———— I was able to drain a couple of the cells some but don’t think that reduced any of the swelling. I think the tight box must have saved me and kept them from bursting open. I was eventually able to extract one of them using a little motor oil and elbow grease. The cells are in tact...

Just a regular socket with a couple of wires should work?

Should I be able to connect an inverter you think?

Yes, but I accidentally bypassed it.

I have some dumb appliances. Would I simply connect wires from pos/neg from the individual cells to an extra outlet and plug in the appliance?

Thanks for the link. to the other post. I don't know how high they got. I set things up last night then came back to this and quickly disassembled. The highest I currently see is 3.95 v (correction from my earlier post of 3.8).

Willing to give it a try. A little afraid to reconnect the individual cells. Can I drain them individually and any guidance on how to do that would be welcome. The voltage is all over the board with them but they are up to 3.8v

I made a bad mistake overnight and ruined my battery that is installed in my van. See photos. I need advice on how to safely remove these cells. They are completely wedged in since they are so far swollen. Will the swelling go down? How long will that take? It has only been a couple hours...

I just ran a test. set the BMS cell over voltage higher so I was pretty sure it wouldn't trip put my multi-meter on the battery started the van to charge and monitored both BMS and multi-meter Results and observations: charging continued at 300-400 watts until my multi meter read 14.38 where...

Ah. I see. Not connected. While the manual notes this exists it doesn’t mention anything about connecting.

That screenshot may have been when the battery was still on the workbench and resting after charge and top balance. :)

Thanks. Just confirmed that I am using these setting. Sorry. I don't understand the question. Are you suggesting I disconnect the balance cables and bus bars and read the cells?

That makes sense. I used the setting recommended by the BMS reseller. What would you say is "slightly higher"? I set it to 14.60 for the cutoff for the entire pack. I put screen shots in my other response and am interested in your thoughts. I am using the Lithium setting on the Renogy...

Thank you @gnubie and @smoothJoey This is all very helpful. I think I may be on to something but it raises more questions. I have screenshots from the BMS app from two different days. The first screenshot from about 20 days ago shows the cells well balanced. I think this was a>24 hours after...

The BMS seems to be correctly reading the cell voltage an shutting off the battery appropriately. I don't remember the exact voltages of each cell but when the over voltage protection kicks in one cell has been at 3.65 and the other three pretty close to that. Yes, my multimeter agrees with...

I guess when I think about it, my real question is "is this the proper way the battery is supposed to be charged and is it safe and healthy?" I assumed the BMS or charge controller would prevent the cells from ever hitting the 3.65 and that when this happens the cell is either unsafe or being...

Hi all, I built a 120Ah battery using the Overkill Solar BMS (also sold in many flavors from Alibaba) and installed in my camper van. Once the battery is at 100% and the van still running (alternator charging) the "cell over voltage" protection from the BMS frequently kicks in and stops...

Okay. After 24 hrs, they are all at 3.57. Does that seem about right?

My voltmeter only has 2 decimal places But reads 3.63 for each cell.

Clearly I need to be more patient before posting. Took several days but looks good now.

Thanks for the feedback. Something still doesn’t seem right. Keep in mind that I have no idea what I am doing ;). I was making no progress balancing the four cells. By this, I mean that the current on my power supply simply wasn’t going down, so I tried something. I disconnected the cells and...

my voltmeter says 3.34-3.35 volts fir each cell. I haven’t tested the capacity yet but they are supposed to be 120Ah. in addition the the shit alligator clips and cheap power supply, I had to make a couple of my own bus bars which may be throwing things off a bit.