I’m curious as to why that would be, but I didn’t watch the video a few back yet. Nbd I’ll work through the theory and math.
So this is how I am thinking about it. Demo drawing with 3.2v and 3.1v cells connected/welded together, with both having 0.05 ohm internal resistance. Balancing current becomes 1A. That stackexchange link I posted has the equation in a nicer form.
Anyone got any photos of what their nickel looks like before rounding the edge. I cut my nickel strips long enough to hang over the edges so then I could chomp them easoly, like this
Just seems like a lot of nickel waste adding up doing it like this if chomping that much excess. How do you guys do it?
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Cut them before welding!!
The length to use is 8mm + (n - 1) * cell diameter, and a 4mm radius round
- 2p is 27mm
- 3p is 45mm
- 4p is 63mm
Edit: if the parallel group is not butting up against the next group, you can cut it to match the edge of the cell but there’s no real good reason to do that
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That makes a lot more sense. Seems people were saying to chomp after welding on my earlier posts, woops lol
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I couldn’t even get the nickel into the chompers far enough to cut the edges close enough to the cell with the cells welded on. The cells get in the way, so I don’t see how anybody actually does it this way
I don’t thing anyone does, I just got chompers on Amazon for $15 and they need some lube and TLC before they run smooth but it makes short work of corners…at their chunky size they are only good for straight strip 10mm or we wider
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I can double check, but none of them blew through, the welds are incredibly strong, I would have a hard time pulling them off. Maybe it’s the angle I was holding the electrodes at but sometimes it does make a wider contact weld than I’d like. I was pressing down firmly on all of the welds so I don’t think it was that. I could try cleaning off the tips too. Unfortunately I can’t weld again until I hear back from hobbyking though
So from your point of view, if this is 49J, what kind of decrease in power should I try?
I’d drop it to 40 and see what they look like
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Alright got it. Do you usually just say that they’re “good” if you can leave a circle of nickel when you pull the nickel off a test cell with pliers?
I obviously don’t wanna drop it too low and have a weak bond but I don’t want them burned either. Good thing is I still have a lot more welds to go haha
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Got it haha I’ve got some cells with rust on one side of them them to test on
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I have been considering this charger for a while now. Has it been pretty solid For you?
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Its one of my favorite esk8 things ever. Highly recommend.
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And you gotta take into account for the fact that one cell or group will be charging at whatever current the other one is discharging at. While a 30Q can fairly happily discharge at 20A, if you charge one at 20A it will become quite unhappy in a hurry.
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True I’ve always just tried to get them within 0.1v before bridging them together. It was interesting in the video though how long it actually took for the cells to balance with each other. Imagine how long it would take for like a 7p that wasn’t the exact same voltages
Which charger?
This big boy.
(Haven’t actually charged and used the plug tho, 1/2 way through my build still)
@glyphiks is a bad influence.
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What do you need?