I’ve build a 10s5p battery from mixed 18650 from old laptop batteries, it works fine but as expected, most of the cells only hold 1000 to 1500 mah and their all mixed up. So onto to the next… I’m hoping for advice from someone who’s done that before, I’ve seen single lipo 5000mah cells from hobby king for about 6 bucks each. I’ll reuse the BMS I used for my LiIon pack as it charges to 42v .
you might want to check what is the cut off voltage for the BMS. most people will not discharge their lipo past 3.3V for the longevity of cells. some will absolutely run them down to 3V but that is a little too harsh on the batteries.
I’ll program that into vesc, and have a voltage indicator. I fly quadcopters so and never discharge under ,3.6 Thank you
in that case, it should work. the only thing u have to worry is connecting the batteries. if you do have a spotwelder, i guess u will be facing close to no worries.
if you are gonna solder the battery tabs, you probably need to use some form of aluminium solder. i’ve seen some korean forum that they actually punch holes on to the battery tab and then use a pop rivet to connect them together instead
I’ve got aluminium solder, repaired a few lipos before, but I’m curious now about spot welding the battery tabs??? I’ve got a nice DIY spot welder I used to make my LiIon packs
One piece of advice I can give is make sure you secure those cells down real good and really insulate the tabs. I made a temporary pack with some lipo cells and because they were loose the tabs broke in the middle of a ride. For me, I just lost power, but that can easily turn into a lipo fire if you’re not careful.
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Good shout
Just spotwelder tabs with nickel strips like you normally would with li-ion.
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