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eve 3.2v 280ah 16s 48v

Cuemaker

Cuemaker

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Winchester, Ohio
What should the charge controller voltage be set for EVE 3.2v 16s 48v battery bank?
Aims 100 amp charge controller lithium setting = 57.6v, works great until battery bank gets to 100% SOC.
The thing keeps charging until alarms settings go off at 3.65v per cell, then at 3.7v the whole system shuts down.
Can I use, user define option, just need to know what to set it.
Sorry if this question has been asked before but I couldn't find the answer, I looked until I'm cross-eyed.
Thanks!
 
Cuemaker said:
What should the charge controller voltage be set for EVE 3.2v 16s 48v battery bank?
Aims 100 amp charge controller lithium setting = 57.6v, works great until battery bank gets to 100% SOC.
The thing keeps charging until alarms settings go off at 3.65v per cell, then at 3.7v the whole system shuts down.
Can I use, user define option, just need to know what to set it.
Sorry if this question has been asked before but I couldn't find the answer, I looked until I'm cross-eyed.
Thanks!
Click to expand...

How long ago did you top balance the cells?
 
Last edited:
Cuemaker said:
About 2 months ago.
Click to expand...

If they have been in storage for the majority of that, and even for as little as two weeks, the top balance has likely been lost. Top balances should be done immediately prior to build/commissioning.

Make sure BMS OVP is set to 3.65V/cell and 58.4V for the pack. Some forget to adjust the pack voltage, and it's at a lower value than the per-cell limit.
 
sunshine_eggo said:
If they have been in storage for the majority of that, and even for as little as two weeks, the top balance has likely been lost. Top balances should be done immediately prior to build/commissioning.

Make sure BMS OVP is set to 3.65V/cell and 58.4V for the pack. Some forget to adjust the pack voltage, and it's at a lower value than the per-cell limit.
Click to expand...
The BMS OVP 1st alarm is set at 3.6v & 2nd alarm is set at 3.7v.
If a cell goes to 3.7v the whole system shuts down, it happened once, took me a while to figure out what was going on.
I have been playing with the setting on my charge controller, Aims 100amp 48v, if I get it figured out I will post it.
I have done a lot of research & my understanding is that a BMS will protect the battery bank but will not keep the CC from charging.
Will's suggestion to set CC at 56.4v is only 3.525v per cell but it kept charging & cells reached 3.65v+, so I turned off some solar panels.
Thanks
 
Cuemaker said:
The BMS OVP 1st alarm is set at 3.6v & 2nd alarm is set at 3.7v.
If a cell goes to 3.7v the whole system shuts down, it happened once, took me a while to figure out what was going on.
I have been playing with the setting on my charge controller, Aims 100amp 48v, if I get it figured out I will post it.
I have done a lot of research & my understanding is that a BMS will protect the battery bank but will not keep the CC from charging.
Click to expand...

The way you said this is a bit off. Charging = supplying current to the battery. The BMS blocks any incoming current to the battery thus preventing charging. However, it does not turn the charger off, so if there's other loads drawing from the charger, they can still be powered.

Cuemaker said:
Will's suggestion to set CC at 56.4v is only 3.525v per cell but it kept charging & cells reached 3.65v+, so I turned off some solar panels.
Thanks
Click to expand...

Are you saying the CC is going past the set voltage, or are you saying that even though you're set to 56.4V, some cells are going over 3.65V? If the former, that's a defective charge controller. If the latter, again, that's a symptom of imbalanced cells due to the time elapsed.

Recommend you set to 55.2V bulk/absorb and 54V float. That's 3.45 and 3.375V, respectively. At 3.45V over 2-3 hours, you can get very nearly fully charged (98%+) and that allows some additional time in the balance range. Hopefully, at this lower voltage, you will not experience voltage alarms/shutdowns. If you do, you need to directly address the cell imbalance by charging the low cells with your power supply, or bleeding off the high cells with resistor(s) or 12V light bulbs. You can do either without disassembling battery.
 
sunshine_eggo said:
The way you said this is a bit off. Charging = supplying current to the battery. The BMS blocks any incoming current to the battery thus preventing charging. However, it does not turn the charger off, so if there's other loads drawing from the charger, they can still be powered.



Are you saying the CC is going past the set voltage, or are you saying that even though you're set to 56.4V, some cells are going over 3.65V? If the former, that's a defective charge controller. If the latter, again, that's a symptom of imbalanced cells due to the time elapsed.

Recommend you set to 55.2V bulk/absorb and 54V float. That's 3.45 and 3.375V, respectively. At 3.45V over 2-3 hours, you can get very nearly fully charged (98%+) and that allows some additional time in the balance range. Hopefully, at this lower voltage, you will not experience voltage alarms/shutdowns. If you do, you need to directly address the cell imbalance by charging the low cells with your power supply, or bleeding off the high cells with resistor(s) or 12V light bulbs. You can do either without disassembling battery.
Click to expand...
I tried that setting 55.2v bulk/absorb & 54 float.
Results were pretty good, it charged to 99.1%, all cells stayed within 20mv.
But when every cell reached about 3.435v voltage spread started to widen.
What seems to work best is 54.8v bulk/absorb & 54 float, it charges to 95% then transfers to float.
Voltages on cells drops a little but SOC continues rise slowly.
I'm happy with this setting if it doesn't damage the cells, I don't think it will.
Thanks
 
Cuemaker said:
I tried that setting 55.2v bulk/absorb & 54 float.
Results were pretty good, it charged to 99.1%, all cells stayed within 20mv.
But when every cell reached about 3.435v voltage spread started to widen.
What seems to work best is 54.8v bulk/absorb & 54 float, it charges to 95% then transfers to float.
Voltages on cells drops a little but SOC continues rise slowly.
I'm happy with this setting if it doesn't damage the cells, I don't think it will.
Thanks
Click to expand...

It's clear you're having balance issues. 54.8V should give you at least a little balancing. For 7 days, I would set float to 54.7V. After 7 days, try 55.2V and see if the behavior is less divergent.
 
sunshine_eggo said:
It's clear you're having balance issues. 54.8V should give you at least a little balancing. For 7 days, I would set float to 54.7V. After 7 days, try 55.2V and see if the behavior is less divergent.
Click to expand...
Solved my cell balancing problems by dumping my Daly BMS.
After much research I went with Overkill BMS, Will's videos & being approved for medical use sold me, works great!
My question now is where to set my charge controller, had it set at 56v bulk, absorb & float.
The delta between cells would stay within 10mv, but when some cells reached 3.5v the delta will climb to around 50mv.
I reset the CC to 55.6 bulk, absorb & float, it work better but the delta still went up once a few cells hit 3.5v.
Set at 55.2v it didn't fully charge, I'm thinking about setting bulk & absorb at 55.6v & float at 55.2v.
What do you think, can I set the float voltage different from bulk & absorb?
During top balancing 3.45v is when the voltage shoots up.
Thanks
 
Hey stranger.

55.2V should be enough to hit full or near full charge after a couple hours of absorption.

Float should never be the same as bulk/absorption unless you're trying to correct an issue. 54V float if you don't want more balance time, 54.4V if you want a wee bit of balancing.
 
sunshine_eggo said:
Hey stranger.

55.2V should be enough to hit full or near full charge after a couple hours of absorption.

Float should never be the same as bulk/absorption unless you're trying to correct an issue. 54V float if you don't want more balance time, 54.4V if you want a wee bit of balancing.
Click to expand...
Set to 55.2v bulk/absorb & 54.4 float.
Supposed to be sunny the next couple days will see what happens.
Thanks
 
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