I´m planning to build a 72v 20ah (only around 20ah due to limited space). I have never build a battery pack before so I have been doing quite a lot of research but I can´t seem to figure out the best cells to use.
I´ve been looking at Samsung 21700 40t cells because a lot of people recommend them and because I will be able to draw a lot of amps from a batterypack made by these cells using the copper nickel sandwich method. However if I use these cells (or any other 21700/18650 cells) I will have to invenst in a spotwelder. I have been looking at a kWeld with the Turnigy lipo battery recommended on the kWeld website and the total cost for welder and battery including freight cost will be around 400 euros. Since I don´t know how many battery packs I will be building this seems a little bit expensive and it got me thinking that there might be other ways of building good battery packs without spot weldning? I´ve seen people using eig c020b cells for example with bus bars that screws on to the cells. Eig c020b seems impossible to find and order but maybe there are other similar cells? I have been looking at some Lifepo cells that also allows bus bars to be screwed in place but it seems hard to find Lifepo cells that are as space efficient as the Samsung 40t? Another thing is that I live in Europe so I would prefere a EU (or possibly a Chinese) supplier.
Any help is appreciated!
I´ve been looking at Samsung 21700 40t cells because a lot of people recommend them and because I will be able to draw a lot of amps from a batterypack made by these cells using the copper nickel sandwich method. However if I use these cells (or any other 21700/18650 cells) I will have to invenst in a spotwelder. I have been looking at a kWeld with the Turnigy lipo battery recommended on the kWeld website and the total cost for welder and battery including freight cost will be around 400 euros. Since I don´t know how many battery packs I will be building this seems a little bit expensive and it got me thinking that there might be other ways of building good battery packs without spot weldning? I´ve seen people using eig c020b cells for example with bus bars that screws on to the cells. Eig c020b seems impossible to find and order but maybe there are other similar cells? I have been looking at some Lifepo cells that also allows bus bars to be screwed in place but it seems hard to find Lifepo cells that are as space efficient as the Samsung 40t? Another thing is that I live in Europe so I would prefere a EU (or possibly a Chinese) supplier.
Any help is appreciated!