So I'm wondering if I could go 12v... 4 separate 12v batteries (with a bms on each pack) and parallel those 4 into 1 battery? (16 280ah batts) Is it possible and safe? I would like to stay 12v because I have a Victron 12/3000/120 in a Camper..I realize I might have to go 24v but I wonder if this is possible? Thankyou in advance!
12v 4s4p.....4p4s?
- Thread starter railcon56
- Start date
MisterSandals
Participation Medalist
Batteries or cells?
This is 16 cells.
If you don't use the right words your bicycle will parachute until a gallon.
Cells ty
Many on here do this using the overkill BMS. It will work fine. You just need to plan to balance the multiple packs as needed as they will drift a bit.
You end up with the same configuration as if you bought 4 Battleborns and put them in parallel.....
Northernchateau
Solar Enthusiast
The simple answer is yes, you can take your 16, 280 ah cells to supply 12 volts.
My suggestion is, take 4 cells, add a 120 amp (or bigger) BMS (Overkill or Daly) take the 12v output and connect to a Buss Bar.
Do the same with all cells. That means you have 4 BMS outputs connected to the same Buss Bar.
280ah @ 12v x 4 batteries packs = 1.120 ah @ 12v
Now that Vitron will need 250 amps for 3000 watt output so make sure you size a fuse/breaker and wire size accordingly.
If your using your camper below freezing make sure you select a BMS like the Overkill with a temperature probe.
www.altestore.com
My suggestion is, take 4 cells, add a 120 amp (or bigger) BMS (Overkill or Daly) take the 12v output and connect to a Buss Bar.
Do the same with all cells. That means you have 4 BMS outputs connected to the same Buss Bar.
280ah @ 12v x 4 batteries packs = 1.120 ah @ 12v
Now that Vitron will need 250 amps for 3000 watt output so make sure you size a fuse/breaker and wire size accordingly.
If your using your camper below freezing make sure you select a BMS like the Overkill with a temperature probe.
Wire Sizing Chart for 12V/24V/48V DC Systems - DIY Solar Resources
Information on wire sizing and a universal AWG/mm2 wire sizing chart to help in designing a 12V, 24V, or 48V DC renewable energy system.
www.altestore.com
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
12V system @ 250A produces 3000W or 25A @ 120VAC, 17.5A at 240VAC (uncorrected)
4 separate packs attached to a DC-Bus creating a Battery Bank of 4 packs, will allow the 4 packs to share both the Charge & discharge evenly.
All BMS' within the Battery Bank should be identically configured so they march in perfect step together.
We suggest not to exceed 250A draw capacity and for good reasons and I won't get into a well-beaten topic. (excluding surge capacity)
You have 280AH - 280A output capable batteries that can fill that requirement. Every single pack should be able to act as "The Last Man Standing" so that none will ever get over driven even if all other packs in the bank cutoff for any reason. IT HAPPENS !
Now with 4 packs and 250A capable BMS, that can deliver a MAX of 1000A which is more than enough for any surge...
12V@250A=3,000W and with a LOW Frequency Inverter that can goto 9,000W (750A), High Frequency can hit 6,000W or 375A.
No to be mean or nasty or anything BUT this is a decision that could cost you serious coin if having to upgrade and worse if cells get damaged due to poor config and NOT preplanning for "Worst Case Scenarios" which sadly DO HAPPEN ! Be Smart and consider this and weigh the choices carefully. These are "System Foundation Essentials" to be aware of. Like a house, the Foundation has to support everything that is loaded on top of it which includes all the crap that people stuff into buildings (which often weigh more all tallied up than the actual building) pending on construction type.
Hope it helps, Good Luck
Steve
4 separate packs attached to a DC-Bus creating a Battery Bank of 4 packs, will allow the 4 packs to share both the Charge & discharge evenly.
All BMS' within the Battery Bank should be identically configured so they march in perfect step together.
We suggest not to exceed 250A draw capacity and for good reasons and I won't get into a well-beaten topic. (excluding surge capacity)
You have 280AH - 280A output capable batteries that can fill that requirement. Every single pack should be able to act as "The Last Man Standing" so that none will ever get over driven even if all other packs in the bank cutoff for any reason. IT HAPPENS !
Now with 4 packs and 250A capable BMS, that can deliver a MAX of 1000A which is more than enough for any surge...
12V@250A=3,000W and with a LOW Frequency Inverter that can goto 9,000W (750A), High Frequency can hit 6,000W or 375A.
No to be mean or nasty or anything BUT this is a decision that could cost you serious coin if having to upgrade and worse if cells get damaged due to poor config and NOT preplanning for "Worst Case Scenarios" which sadly DO HAPPEN ! Be Smart and consider this and weigh the choices carefully. These are "System Foundation Essentials" to be aware of. Like a house, the Foundation has to support everything that is loaded on top of it which includes all the crap that people stuff into buildings (which often weigh more all tallied up than the actual building) pending on construction type.
Hope it helps, Good Luck
Steve
You are going to have 16 cells. You are trying to decide how many batteries.
Not being a pain, but there is a big difference.
I prefer multiple batteries myself, but it is up to you. Daly is a crapshoot due to poor quality control, inadequate documentation and just "we got your money, we don't care" attitude. JBD (aka Overkill) doesn't have a model that could handle a 3000 watt inverter at 12v by itself, so it would require multiple parallel batteries. There are other options as Steve pointed out, in particular when you get above 200 amps of current, a FET based BMS is easy, but may not be the best choice.
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