I saw in a lot of youtube videos people using capacitors connected in parallel to make use of the current for a spot welder for battery tabs, I was checking my cemetery box last night and found a lot (like 60) Li ion 18650C4 batteries, they are rated for 2200mA and 4.2V nominal, I think that's a lot, if I put 60 of them in parallel, now, I'm worried for the stress I would be imposing on the bank, perhaps a low resistance high wattage lamp would alleviate the near zero resistance at the end? or is this a no no, don't do it project? I can also use them for other things, like a battery powered mini car for my kids, but what I need right now is a spot welder for fixing laptop batteries in my computer shop at the end of the world :) , I have no trouble charging them and I have been using batteries for a long time charging and discharging them with a constant current charger and limited voltage power supply, plus a temperature sensor, just in case.
Fixing batteries with a spotwelder is frequently done with large capacitor banks. The capacitorbank solves two problems at the same time.
- During spotwelding (for fixing a battery cell) a large to very large current is available.
- In case something goes wrong (when fixing a battery cell) the large current is reduced to low when the capacitors are discharged.
With a large battery made of Li-Ion cells you would be able to reach target 1.
However when something goes wrong this battery would keep on supplying large currents. That would form a large risk in terms of fire hazard. For me is therefore a DONT.