hi
I need to build yet another battery pack and want to check which is the best way to go.
the pack will be a 72v 20ah LiPo pack it will be in the 20S 4P configuration using turnigy 20c 5ah cells. The BMS and charger are sorted.
The problem I have is what cells do I use multi cell battery packs complete with balance and power wires, thepacks will be striped of there covering then the wires will get removed and replaced with a better choice of wiring that takes up less room or go for individual cells https://hobbyking.com/en_us/turnigy-5000mah-1s-20c-lipoly-single-cell.html. Both routes will give the same result size of pack, there are pros and cons with both ways.
Time: Similar for both packs ripping the multi packs apart soon cancels out the extra time to solder the pack.
Balanced cells: with multicell battery packs the cells in each pack will be matched but not necessarily matched between packs, with the single cell route you don't know if the cells are matched. how much does it really matter with a good BMS.
Cell replacement: single cell building definitely wins there multi cells are stuck together and the contacts welded making cell replacement very hard better to just replace the pack an extra expense.
Pack shape: with single cells the shape of the pack can be more adaptable.
when building custom battery packs out of Li Ion for a large pack a huge box of cells are bought no knowing how well matched they are, these are then linked in in both parallel and series usually by welding.
Single cell LiPo's are the cheapest option but are there hidden problems I have not foreseen.
geoff
I need to build yet another battery pack and want to check which is the best way to go.
the pack will be a 72v 20ah LiPo pack it will be in the 20S 4P configuration using turnigy 20c 5ah cells. The BMS and charger are sorted.
The problem I have is what cells do I use multi cell battery packs complete with balance and power wires, thepacks will be striped of there covering then the wires will get removed and replaced with a better choice of wiring that takes up less room or go for individual cells https://hobbyking.com/en_us/turnigy-5000mah-1s-20c-lipoly-single-cell.html. Both routes will give the same result size of pack, there are pros and cons with both ways.
Time: Similar for both packs ripping the multi packs apart soon cancels out the extra time to solder the pack.
Balanced cells: with multicell battery packs the cells in each pack will be matched but not necessarily matched between packs, with the single cell route you don't know if the cells are matched. how much does it really matter with a good BMS.
Cell replacement: single cell building definitely wins there multi cells are stuck together and the contacts welded making cell replacement very hard better to just replace the pack an extra expense.
Pack shape: with single cells the shape of the pack can be more adaptable.
when building custom battery packs out of Li Ion for a large pack a huge box of cells are bought no knowing how well matched they are, these are then linked in in both parallel and series usually by welding.
Single cell LiPo's are the cheapest option but are there hidden problems I have not foreseen.
geoff