LIFEPO4 Battery discussion thread

wingnut771 said:
Minimum 3.45V.

I'm so happy we getting somewhere and disappointed in myself for not rtfs when he posted app screenshot showing balancer setting.
Click to expand...
As long as the bloody full and charge voltage is not above 57 gheez dunno what they are smoking
 
DTBA said:
As long as the bloody full and charge voltage is not above 57 gheez dunno what they are smoking
Click to expand...
We still in the wind with bat 3 as it has no app hence the hold overnight with 56V request to see if cell balance improves at all.
 
Okay I hit ovp on bat3. I was trying to control it so highest sits below 3.65v but it just briefly touched it and bms disconnected.

Screenshot 2026-05-22 190719.png
 
wingnut771 said:
That's why I said to aim for 3.5V cell voltage. 3.5 is high enough.
Click to expand...

Okay all 3 batteries are connected now. Battery 2 still has the imbalance but it seems spread. Bat3 has a big deviation but limited to 1 or 2 cells. Looks like Bat3 still has ovp disconnect on not sure but I don't see the alarm light.

I think I need to use the pace windows tool to try and connect to these other 2 batteries and adjust the parameters a bit so they all allign.

Screenshot 2026-05-22 192405.png
 
cavedog said:
Okay all 3 batteries are connected now. Battery 2 still has the imbalance but it seems spread. Bat3 has a big deviation but limited to 1 or 2 cells. Looks like Bat3 still has ovp disconnect on not sure but I don't see the alarm light.

I think I need to use the pace windows tool to try and connect to these other 2 batteries and adjust the parameters a bit so they all allign.

View attachment 1910002
Click to expand...
They should all be similar voltage. I see bat 3 volts is 0.7V lower. Problem with cable? Anyway, leave it at this voltage overnight and see imbalance in morning if its less than 154.

edit: could be the ovp disconnect you mentioned. Try putting load on it to drop voltage a bit.
 
wingnut771 said:
They should all be similar voltage. I see bat 3 volts is 0.7V lower. Problem with cable? Anyway, leave it at this voltage overnight and see imbalance in morning if its less than 154.

edit: could be the ovp disconnect you mentioned. Try putting load on it to drop voltage a bit.
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When the ovp gets hit on the new bms they turn of the charge mos so the voltage will settle a bit down.

Now the problem is if he keeps the voltage on 55V the charge mosfet wont turn on because the battery SOC reset to 100%

So it will not charge again tonight.
Balancer will run. But man that battery3 is bad
 
cavedog said:
Okay all 3 batteries are connected now. Battery 2 still has the imbalance but it seems spread. Bat3 has a big deviation but limited to 1 or 2 cells. Looks like Bat3 still has ovp disconnect on not sure but I don't see the alarm light.

I think I need to use the pace windows tool to try and connect to these other 2 batteries and adjust the parameters a bit so they all allign.

View attachment 1910002
Click to expand...
Is the cell that hit ovp the same cell that hit uvp?
 
wingnut771 said:
They should all be similar voltage. I see bat 3 volts is 0.7V lower. Problem with cable? Anyway, leave it at this voltage overnight and see imbalance in morning if its less than 154.

edit: could be the ovp disconnect you mentioned. Try putting load on it to drop voltage a bit.
Click to expand...
Thats what my edit was about, drain it a bit so mosfets turn back on then maintain 54V overnight and see if balancer does anything.

bat 2 isnt much better, lets see in the morning.
 
wingnut771 said:
Thats what my edit was about, drain it a bit so mosfets turn back on then maintain 54V overnight and see if balancer does anything.

bat 2 isnt much better, lets see in the morning.
Click to expand...
If he has a cable you can turn the charge mos on via pbms tools
 
DTBA said:
If he has a cable you can turn the charge mos on via pbms tools
Click to expand...
On second thought just leave it like it is overnight. KISS and maybe fets will turn back on overnight and voltage all be equal in morning and hopefully imbalance has come down.
 
DTBA said:
Is the cell that hit ovp the same cell that hit uvp?
Click to expand...

No cell08 hit uvp but cell15 hit ovp.

I connected to the BMS now. My God they had the worst settings 3.7v ovp per cells. Balance only starts at 3.6v o_O I changed them now.

Screenshot 2026-05-22 202949.png

Screenshot 2026-05-22 202934.png
 
wingnut771 said:
Thats what my edit was about, drain it a bit so mosfets turn back on then maintain 54V overnight and see if balancer does anything.

bat 2 isnt much better, lets see in the morning.
Click to expand...

cavedog said:
No cell08 hit uvp but cell15 hit ovp.

I connected to the BMS now. My God they had the worst settings 3.7v ovp per cells. Balance only starts at 3.6v o_O I changed them now.

View attachment 1910025

View attachment 1910026
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Did you reset the SOH? Anyways yea the battery cells are probably just fine. Scored your self nice battery for the price just needs a good balance
 
DTBA said:
Did you reset the SOH? Anyways yea the battery cells are probably just fine. Scored your self nice battery for the price just needs a good balance
Click to expand...

Yes I reset the SOH and SOC. I would probably need to do it again once it's balanced at 3.45v per cell

wingnut771 said:
How low does this go?
View attachment 1910030

and wonder what this is:
View attachment 1910031
Click to expand...

20mV is the lowest it can go. It was on 30 I changed it to 20.

Oops I made a mistake with current capacity. 10Ah :whistling:

Screenshot 2026-05-22 205828.png
 
DTBA said:
20

Also the bottom one I think is that cell is not allowed to get touch by a balancer? I might be totally wrong
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Cant be, it should stop below 3.45V. 3.15V is almost an empty battery. It would never balance if it stopped at 3.15V.

Sometimes there are settings that make no sense and have no answer. It is the chinese way.
 
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