5AH 26650 4S2P 4.6Ah Battery Cassette LiFePO4 by davepix

Last crawled date: 3 years, 1 month ago

WARNING: Lithium batteries can explode or catch on fire, they can dump massive amounts of power, will melt things and burn up your devices. Build and use at your discretion, this is a record of what I have done not a suggestion that you do it.
Battery cassette built to retro fit a Profoto Acute B originally equipped with a PB cell to Li for under $650 which Profoto charges for their battery. The cassette is held together with two screws and a lots of kapton tape... also necessary because the original cassette frame is metal, the PCB is otherwise exposed on the side and the inside of the generator if fits in is metal... metal everywhere!
This was built for just around $100
25560 cells can be bought in several chemistries. LiFePo4 gave me comparable voltage to the original PB. I had wanted to use a different cell made by Nitecor originally but thought 3.7V cells combined to make 16V might increase the chance of catastrophic failure.
Battery balance and protection PCB
https://www.batteryspace.com/pcbpcmfor128vlifepo4pack4inseries.aspx
How to wire ithttp://www.batteryspace.com/prod-specs/pcb_wiring.pdf
The 26650 cells I used. You can buy A123 cells, same capacity for double the price. The reviews on these is good, I'll tell you next year how they held up.http://www.all-battery.com/Tenergy3.2V2500mAh8WhLiFePO4IFR26650PRechargeableBattery-30061.aspx
Note: the battery normally goes inside the rig powerpack. I have it wired externally to test it... I'll have to upload the files for the rig perhaps...