Alright, this is not a prooven method thus yet, but my initial results are very promising, so i figured i would post up the idea to get some feedback from you guys before i assemble my larger ebike packs... This idea came to mind a few days ago when my lipo 2.2aH pack took a dump on me after flying my RV plane, didnt have anymore packs laying around since i dont fly it often... so i took a few of the 18650 cells out of the pile that i deemed to far gone for my ebike (1500-1000mah) and made a quick 4 cell pack from the 18650 cells, initially i was going to solder them to the ends of the pack, but i couldnt find my solder that day and my friend wanted to meetup and do some flying, so out of scrambling around i took 2 of the 1/8" x 1/16" N35 magnets i had for connecting the imax b6 to cells and i crushed the end of the stranded wires so they were flat, then i placed the fan of wires between 2 of the magnets like a sandwiche, then connected the magnets to the ends of the cells put a bead of hot glue on the ends so they couldnt easily fall off.... this actually worked and i was able to fly the plane for a few hours this way messing around and charging the battery in the car with the imax.. this is where i got the idea from.....
Then that night i was searching for my solder and found it, so i was curious if i could solder the wires to the magnets, so i drilled a hole into a piece of wood i had just large enough to allow me to slip the tiny magnets in the holes and placed a length of wire across the magnets and soldered the wire directly to the magnets with the spacing of the cells... then i was able to connect the wire to the 18650 cells by connecting the magnets to all the ends and placed a moderate bead of hot glue over the entire end of the battery to keep the magnet secured.. I assembled 3 packs this way very quickly and easy using the jig i made to space the magnets out and have used them to fly and have tossed the packs around the yard to see if i could jar the connections loose with brutal impacts and thus far the packs are staying securely connected using the magnets and hot glue....
So i am curious what you guys have to say about this idea, its not spot welding, i know and its not soldering the cells, as the heat is applied off the cells.. but it seems to work and these magnets are dirt cheap... I bought a pack of 200 of the 1/8" x 1/16" N35 magnets off ebay for $4.99 and there are listing for 400 at $6.99 from the same seller.. so way cheaper than buying or building a spot welder..
The other positive i see from this is this, i have read a few postings on this site about people having duffed cells in their packs after a while and the frustration they go through having to desolder or rip the spot welded tabs off of 20 or 30 cells to get the one bad cell out, then having to resolder or spot weld the pack back together.. using this method i would just peel the hot glue off, then pull all the magnets off the ends of that string of cells, pull them out of the pack and test them, place them back in, reuse the wire with the magnets to reconnect all the cells and glue the ends, be in and out in no time..
Then that night i was searching for my solder and found it, so i was curious if i could solder the wires to the magnets, so i drilled a hole into a piece of wood i had just large enough to allow me to slip the tiny magnets in the holes and placed a length of wire across the magnets and soldered the wire directly to the magnets with the spacing of the cells... then i was able to connect the wire to the 18650 cells by connecting the magnets to all the ends and placed a moderate bead of hot glue over the entire end of the battery to keep the magnet secured.. I assembled 3 packs this way very quickly and easy using the jig i made to space the magnets out and have used them to fly and have tossed the packs around the yard to see if i could jar the connections loose with brutal impacts and thus far the packs are staying securely connected using the magnets and hot glue....
So i am curious what you guys have to say about this idea, its not spot welding, i know and its not soldering the cells, as the heat is applied off the cells.. but it seems to work and these magnets are dirt cheap... I bought a pack of 200 of the 1/8" x 1/16" N35 magnets off ebay for $4.99 and there are listing for 400 at $6.99 from the same seller.. so way cheaper than buying or building a spot welder..
The other positive i see from this is this, i have read a few postings on this site about people having duffed cells in their packs after a while and the frustration they go through having to desolder or rip the spot welded tabs off of 20 or 30 cells to get the one bad cell out, then having to resolder or spot weld the pack back together.. using this method i would just peel the hot glue off, then pull all the magnets off the ends of that string of cells, pull them out of the pack and test them, place them back in, reuse the wire with the magnets to reconnect all the cells and glue the ends, be in and out in no time..
