First use of cells

[Kiki387]

I will install my grade A + cells in a Seplos Bms 2.0 box is that if I invest in a Neey 4A active balance box I can do without a top balance it will prevent me from buying a laboratory power supply

 

[houseofancients]

I will install my grade A + cells in a Seplos Bms 2.0 box is that if I invest in a Neey 4A active balance box I can do without a top balance it will prevent me from buying a laboratory power supply

So..
Let me make sense of this
You have 16 new grade a cells
You have a seplos Mason 280 diy kit for the cells
You have a neey 4a active balancer

You want to know if you need to top balance your cells before putting them in the mason, and if you can use the neey to perform the balancing for you

No. You do not need to top balance first and the neey will get your cells in balance for you

This is what I have been doing
Few tips :
1 do your initial charge based of voltage, choose a charging voltage of 56v
2 disable the passive balancing switch in the BMS
2 set your neey to the correct voltages
Start 3.45
Stop 3.40
Diff 2 mv
3 charge to 56v and keep your battery there for 5-6 hours ( or untill the balancer is done)
4 after all you cells are balanced change charging voltage to 56.8. be patient, if your pack reaches 56.8 and stays there for 30 minutes, your SOC will reset too 100%
5 discharge untill the BMS shutsdown discharging , your BMS in now trained
6 charge, still using voltage using 56.8 v until 50%, enable communication in the inverter
7 Change total-pack-overvoltage-protect to 56.8
8 enable passive balancer
9 disable neey
10 enable communications

You are good to go !

 

[Kiki387]

Thanks a lot.
In fact I haven't ordered the neey yet, if I understand correctly it's essential…

 

[houseofancients]

Thanks a lot.
In fact I haven't ordered the neey yet, if I understand correctly it's essential…

Not really, unless you want to skip top balancing, or want to be future proofing a bit

 

[740GLE]

Even then any BMS worth owning should be able to handle a bit of unbalanced cells.

It’s just a matter of time to let a BMS do its magic.

 

[hwy17]

You can also build without an active balancer or parallel top balancing.

Just dial the first charge up carefully and observe. Charge to 53v, check BMS for balancing cells, wait, charge to 54v, check for balancing cells, wait, charge to 55v, check for balancing cells, wait. The balance voltage here should be your final intended balance voltage, and not say 53/16 for the 53 volt charge. You only want to be balancing cells that are exceeding the final intended balancing voltage. For me it's balance above 3.437 but a lot of people use like 3.4+.

My pack took something like 6-18 hours to balance the first time, with 150mA balancing current.

There is also a different strategy where you just charge straight to 55 or 56 and let the BMS peg against the high cell limit, repeatedly interrupting the charging. That sounds kind of aggressive to me. I'd rather watch and baby it.

 

[houseofancients]

You can also build without an active balancer or parallel top balancing.

Just dial the first charge up carefully and observe. Charge to 53v, check BMS for balancing cells, wait, charge to 54v, check for balancing cells, wait, charge to 55v, check for balancing cells, wait. The balance voltage here should be your final intended balance voltage, and not say 53/16 for the 53 volt charge. You only want to be balancing cells that are exceeding the final intended balancing voltage. For me it's balance above 3.437 but a lot of people use like 3.4+.

My pack took something like 6-18 hours to balance the first time, with 150mA balancing current.

There is also a different strategy where you just charge straight to 55 or 56 and let the BMS peg against the high cell limit, repeatedly interrupting the charging. That sounds kind of aggressive to me. I'd rather watch and baby it.

With a seplos there is no need to baby..
It has a hardware based 10a charge limiter that will kick in when a cell hits alarm status ( which is not over voltage protection !)

Not sure where OP got his cells, but true grade a is rare and passive 200Ma isn't a lot.
It can take a huge amount of cycles to balance with a passive balancer at that rate

 

[Kiki387]

That's it I received my cells and I have to make my first charge I have questions however because I misunderstood how to make a charge on the voltage with my victron for:
do your initial charge based of voltage, choose a charging voltage of 56v, I set dvcc to 56v, right?

 

[Kiki387]

So..
Let me make sense of this
You have 16 new grade a cells
You have a seplos Mason 280 diy kit for the cells
You have a neey 4a active balancer

You want to know if you need to top balance your cells before putting them in the mason, and if you can use the neey to perform the balancing for you

No. You do not need to top balance first and the neey will get your cells in balance for you

This is what I have been doing
Few tips :
1 do your initial charge based of voltage, choose a charging voltage of 56v
2 disable the passive balancing switch in the BMS
2 set your neey to the correct voltages
Start 3.45
Stop 3.40
Diff 2 mv
3 charge to 56v and keep your battery there for 5-6 hours ( or untill the balancer is done)
4 after all you cells are balanced change charging voltage to 56.8. be patient, if your pack reaches 56.8 and stays there for 30 minutes, your SOC will reset too 100%
5 discharge untill the BMS shutsdown discharging , your BMS in now trained
6 charge, still using voltage using 56.8 v until 50%, enable communication in the inverter
7 Change total-pack-overvoltage-protect to 56.8
8 enable passive balancer
9 disable neey
10 enable communications

You are good to go !

That's it I received my cells and I have to make my first charge I have questions however because I misunderstood how to make a charge on the voltage with my victron for:
do your initial charge based of voltage, choose a charging voltage of 56v, I set dvcc to 56v, right