Need help calculating discharge rate for EVE 280 cells

[Jamie.sanders]

I need help I have read that The EVE-280AH Cells can discharge up to 1C-Rate or 280A for a max of 1 hour?
1st question, is that 280A per cell? with lets say 4 cells in a 12 volt battery, I believe the answer is no, that number is for a 4 cell 12v assembled battery?

2nd question, not sure how the exponential goes? I have three, 24 volt batteries (a total of 24 cells) EVE-280AH Cells, how do I calculate the discharge rate?
would it simply be 280AH x 6 ( since my cells would also make six, 12 volt batteries), any advise would be greatly appreciated.

 

[740GLE]

Current per battery series string be it 12v 24v 48v or higher, so 280x3, but that’s also assuming you have quality bus bars/connections per battery and cell.

Butttt, what BMS are you using per battery unit, assuming you have three batteries units.

What interconnection cabling/bus bars do you have? Can it support 280x3 amps?

 

[Bob B]

When cells are in series .... as 4 would be to make a 12V pack ... or 8 would be to make a 24V pack .... the current is the same in all cells .... and the limit would be 280 A.

If you have 3 24V 280 A packs and put them in parallel ... now the current capability increases. So, you would theoretically have 840 A capability (3 X 280) .. if you have the ability to wire if for that.

Most would design a 3 pack parallel system so that any one pack could still handle the load.

 

[Jamie.sanders]

When cells are in series .... as 4 would be to make a 12V pack ... or 8 would be to make a 24V pack .... the current is the same in all cells .... and the limit would be 280 A.

If you have 3 24V 280 A packs and put them in parallel ... now the current capability increases. So, you would theoretically have 840 A capability (3 X 280) .. if you have the ability to wire if for that.

Most would design a 3 pack parallel system so that any one pack could still handle the load.

and by a 3pack parallel system you mean, 8 cells wired in series to make 24 volt batteries, (3-24 volt batteries) and put those 3 batteries in parallel wiring configuration correct? sorry I'm learning.

 

[Bob B]

and by a 3pack parallel system you mean, 8 cells wired in series to make 24 volt batteries, (3-24 volt batteries) and put those 3 batteries in parallel wiring configuration correct? sorry I'm learning.

Yes

 

[Johnson]

Assuming that the max charge discharge rate of 1C is correct....

Bob's answer is correct. Think of the max discharge as the maximum current that can run through each battery cell. If the 24 cells are in series, the max current is 280A, if the 24 cels are in parallel the max current rating would be 6720A (280*24) So if you have 3 sets of 8 cells in series, the max current is 840A (280*3)

 

[Jamie.sanders]

Thanks guys, looks like my 6,000 watt inverter will not be too large or pull too much wattage at all!

 

[John Frum]

Thanks guys, looks like my 6,000 watt inverter will not be too large or pull too much wattage at all!

What is your dc system voltage?
What is the continous rating in amps for each BMS?

 

[Bossrox]

Those 280's in any series volt configuration are still 280 a/hrs so if I read you correct with 3 24v lith banks & you have each bank connected in parallel gives you 840 a/hrs. I'd like to know why you want to know if you can pull 280 in an hour. I don't think they even make a BMS that can pass that much current, that's about 6 1/2 kw but with 3 banks & a 120 amp BMS on each bank would give you that much easily.

 

[Bud Martin]

BTW, 6000W on AC output side of the inverter will pull about 7000W on the DC input side of the inverter due to Inverter efficiency, 85% is typical peak efficiency for inverter.

 

[740GLE]

So a 6k inverter running at 24v. IMO you should be running a 48v system.

You still need to verify all cabling, bus bars and BMS can support the current draws.

What are you running the required a 6k inverter?

 

[bgflyguy]

That's about 250a over 3 batteries. It should be fine if you do it right. I also wouldn't be surprised if the actual inverter capacity was closer to 3 kw. They seem to get over rated.