Top balancing for ages.

[Sanga76]

Hi all.
I have 16 x 310ah cells.
Connected them all in parralel and checked them on charge using a 5amp power supply at 3.6v.
They started at 3.37v and after 4 days they're reading 3.38v
Am I correct in thinking that they should all balance to 3.6v eventually?
And that when it hits 3.6v, as set on the power supply, the amps will go down to 0 and that would be considered "top balanced".
If so, am I to wait weeks at this charge rate?
Thanks for any advice

 

[houseofancients]

patients.

cells ship at 30% charge.
that means every cell may need 213 ah, so a total of 3408 ah

i would highly suggest putting the in series with a bms.
charge untill cut off by bms, then put in parallel and do the last bit
5a is just not enough go-go to do this in a timely fashion.
if you had taken a look at the top balancing guide in the resources section, you would have known this

 

[Shinebox]

5 amps at 3.6vdc = 18 watts. You have a bank capacity of 14,880 watts. Let’s assume your cells started out at 50%. If you divide 7440/18 you get 413.333 AH. Divide that by 24 and you get about 17 days. Mind you this assumes a constant current of 5 amps. As the batteries get topped off and approach the balance voltage the internal resistance will increase, thus lowering the cuurrent traveling into the cells, therefore extending the time to fully top balance.

Bottom line… the those cells and the charger you have, you need to be patient!

As houseofancients pointed out, it’s best to bulk charge them at a higher voltage in series. I have an Aims 24v charger that I do this with, and then switch the cells back to parallel when you see one of the cells (or more) approach the balance voltage.

 

[Sanga76]

patients.

cells ship at 30% charge.
that means every cell may need 213 ah, so a total of 3408 ah

i would highly suggest putting the in series with a bms.
charge untill cut off by bms, then put in parallel and do the last bit
5a is just not enough go-go to do this in a timely fashion.
if you had taken a look at the top balancing guide in the resources section, you would have known this

I forget to add that i connected them in 4P4S, with a BMS, and charged them to 14.2v before starting.
I have followed the top balancing guide to the best of my ability but didn't expect it to take so long.
Sooooo patients. Got it.
thanks for the reply.

 

[S Davis]

I top balanced 8 sets of four EVE 280ah and it took between 72 and 76 hours per set of four with a 10amp power supply and upgraded charging cables.

 

[400bird]

The knee is somewhere around 3.4 volts/cell. Voltage should start climbing quicker soon.