How to arange 16 LiFePo4-Cells (280AH, 3,2V) to 24V?
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gnubie
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You can arrange them as 2 strings of 8 cells to make separate 24V batteries, each with their own BMS and then parallel those batteries. Not all 16 cells shown for ease.
You can arrange them as 2 cells in parallel then put those 8 cell sets in series to form a single high current 24V battery with only one BMS being required. Not all 16 cells shown for ease.
If that's unclear I can include the BMS wiring.
You can arrange them as 2 cells in parallel then put those 8 cell sets in series to form a single high current 24V battery with only one BMS being required. Not all 16 cells shown for ease.
If that's unclear I can include the BMS wiring.
Exactly.
The cells either need to be set into two sets of 8, or parallel the cells in pairs, then have a single string of 8 paired cells.
The cells either need to be set into two sets of 8, or parallel the cells in pairs, then have a single string of 8 paired cells.
GMB
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Assembling a Lithium Iron Phosphate Marine House Bank | Nordkyn Design
This article describes the process of designing, assembling and balancing a lithium battery bank for use on a yacht.
nordkyndesign.com
Prefersdirt
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Today is going to be a good day. I learned something! Did not know of this design. Thank you!
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Did you mean something like this below ?
Of course there are more ways than just this but these show the simple series connections.
Do remember that with 280AH cells, they weigh 5kg/11lbs each.
16 cells will weight in at 80kg (+/- 200g per cell) or 176lbs +/-.
2mm thick busbar will handle up to 150A, 4mm thick will handle 300A .
NOTES:
- The Busbar length between cells 4 & 5 as shown below are longer @ 4.25" while the ones between cells are 3.750"
- I used "COPPER C110 FLAT BAR ASTM-B133 0.125" x 0.750" which is the perfect width to cover the contact pad on the cells.
- Cell Bolt Holes are M6 or 1/4", I drilled mine with 17/32 HSS, Be sure to slot the holes and chamfer them slightly to prevent any ridges etc.
- Apply a small amount of noalox to the contact faces (NOT the bolts) between the cell & busbar to prevent any corrosion potential.
- IF paralleling cells be sure they are Voltage & Impedance Matched, otherwise you will have deviations between the cells in the sets which could cause issues cumulatively later. Paralleling large capacity cells is often more troublesome due to the large capacities & potential deviations between cells. Paralleled cells are managed as an "average" between the cells in parallel, so there is no fine "per cell" management.
Of course there are more ways than just this but these show the simple series connections.
Do remember that with 280AH cells, they weigh 5kg/11lbs each.
16 cells will weight in at 80kg (+/- 200g per cell) or 176lbs +/-.
2mm thick busbar will handle up to 150A, 4mm thick will handle 300A .
NOTES:
- The Busbar length between cells 4 & 5 as shown below are longer @ 4.25" while the ones between cells are 3.750"
- I used "COPPER C110 FLAT BAR ASTM-B133 0.125" x 0.750" which is the perfect width to cover the contact pad on the cells.
- Cell Bolt Holes are M6 or 1/4", I drilled mine with 17/32 HSS, Be sure to slot the holes and chamfer them slightly to prevent any ridges etc.
- Apply a small amount of noalox to the contact faces (NOT the bolts) between the cell & busbar to prevent any corrosion potential.
- IF paralleling cells be sure they are Voltage & Impedance Matched, otherwise you will have deviations between the cells in the sets which could cause issues cumulatively later. Paralleling large capacity cells is often more troublesome due to the large capacities & potential deviations between cells. Paralleled cells are managed as an "average" between the cells in parallel, so there is no fine "per cell" management.
