Calculate the size of battery packs that are made by single cells
All kinds of battery packs are assembled from single cell, we can well adjust the size of battery pack according to customer's space limit.
For example, to make a 48V10Ah LiFePO4 battery pack, we can use 3.2V 10Ah LiFePO4 cell for assembling. We always use 3V as real voltage in calculation, so 48V10Ah pack means 16 pcs of 3V (3.2V) 10Ah LiFePO4 cells, anyway the real pack volt is 16*3.2=51.2V.
Calculating packaged cell size:
Take BP-HK-10E (10Ah LiFePO4 cell) type for example, the original size is 82*12*135mm (Length*Width*Height). When assembling, we need to considerate the space increasing when cells get together, so we add 3mm at length side (82mm+3mm), add 1mm at width side (12mm+1mm). For height we add 15mm(135mm+15mm), because we need to weld tabs with converting boards and adding wires for cells connection, the height increased.
So we can use 85*13*150 mm as size of the packaging cell.
If put 16 cells as 8 line 2 column arrange, total cells size is:
Lengh (8 line): 13*8= 104mm;
Width (2 column): 85*2= 170mm;
Height : 150mm;
Assuming BMS width is 12mm (Most of 12S or 16S type take this 12mm width). We always put BMS/PCB at the top of pack, we also use about 2~3mm isolate materials to separate BMS from batteries as heat isolation.
So, pack size will be increased:
Height would be increased: 150mm (packaging cell) +12mm (BMS width) + 3mm (isolate materials) =165mm
BMS can also be placed at the Length side (the13*8mm side) if size limited.
After all above steps are finished, we will package all of them with materials like shrink film, so each side will be increased about 2mm.
The finished product is:
Length: 104+2*2 (2 sides) =108mm
Width: 170+2*2 (2 sides) =174mm
Height: 165+2*2 (2 sides) =169mm