One Part
https://www.ebay.com/itm/400W-DC-DC-...53.m2749.l2649
400W DC-DC Step-up Boost Converter Constant Current Power Supply LED Driver GD
$6.45
Free shipping
Second Part
https://www.ebay.com/itm/LiFePO4-Li-...53.m2749.l2649
LiFePO4 Li-ion Lithium Cell Battery 18650 Protection Board PCB BMS w/ Balance
$17.10
Free shipping
Third Part
https://www.ebay.com/itm/Box-of-80-F...53.m2749.l2649
Fullriver LiFePO4 26650 3.2V 3300mAh Rechargeable Batteries ( New/Old Stock )
$0.68 each box of 80
$0.19 each for shipping
One note on these batteries I load test them a 1.5 amps for about 30 seconds and the voltage on most of them was about 3 volts or better and this was without charging them first
Fourth Part
26650 Li-ion LiFeO4 battery holder frame anti vibration bracket spacer DIY
https://www.ebay.com/itm/400W-DC-DC-...53.m2749.l2649
400W DC-DC Step-up Boost Converter Constant Current Power Supply LED Driver GD
$6.45
Free shipping
Second Part
https://www.ebay.com/itm/LiFePO4-Li-...53.m2749.l2649
LiFePO4 Li-ion Lithium Cell Battery 18650 Protection Board PCB BMS w/ Balance
$17.10
Free shipping
Third Part
https://www.ebay.com/itm/Box-of-80-F...53.m2749.l2649
Fullriver LiFePO4 26650 3.2V 3300mAh Rechargeable Batteries ( New/Old Stock )
$0.68 each box of 80
$0.19 each for shipping
One note on these batteries I load test them a 1.5 amps for about 30 seconds and the voltage on most of them was about 3 volts or better and this was without charging them first
Fourth Part
26650 Li-ion LiFeO4 battery holder frame anti vibration bracket spacer DIY