LiFePO4 - building my own pack

[numberonekiwi]

Its been a while since I have posted here been into other things like HHO generators etc etc but am now thinking as my original NiMH batteries are getting close to 200 cycles and holding less than 60% capacity its time for new batteries
I have seen prismatic rectangular cells with screw threads somewhere at a price of US$1.10/AH but I think the minimum size is 40AH I am only looking for 20 AH and hoping I can keep that price the advantage of these cells is if one starts to fail I can order another one I may even order a few spare one just for this reason heck $22 for a spare cell worth it I think
The problem is I did not bookmark those suppliers so another day or so to find them again the email about a 20AH cell rather than a 40AH cell

There is one question I would like to ask to all those that have build a pack themselves is the BMS as I understand it monitors each individual cell to min voltage if 1 cell in the pack reaches this point then the whole battery pack shuts down so what would be the best option here for 2x 36V 40A BMS (given a 2C discharge and 2x 36V packs ??

And a question about the charger NiMH also seem to use CC/CV so could my current NiMH charger be used with the correct BMS as cut off seems to be around 43 ~ 45 V

 

[dnmun]

nope, can't use the nicad charger with lifepo4, and if you wanna go 72V then why not just build a 72V pack?

 

[numberonekiwi]

Reason for building 2x 36v packs BMS units are easier to come by there fore being possibly cheaper and the same for chargers also battery packs can be kept separate so I can have one in the triangle frame and one on the rear carrier without to much wiring in between.
Eventually these may get integrated into a tadpole trike.