Also, finger grease, surface gunk, contaminates, not real pure nickel, will infer with the connection that ultimately results in solid, even contact with the nickel and electrodes.
@moddedlife alternatively, and this was critical for my understanding of how these resistive welders work in practice, you can’t muscle through the operation if you press real damn hard with dirty electrodes or thin electrodes. Here, you make great contact, so much so that the tips of the electrodes quickly sink into the nickel (fake or not), the pulse cycle completes with meh resistance and the points of contact don’t heat up that much, bc you forced the contact point to be too favorable for the delivered current.
Wide stubby electrode tips are good bc you can evenly apply an intermediate pressure over a wide area, apply current sufficient to heat up the nickel, terminal interface, and melt those materials together.
I’m not the best educator in a field that isn’t my own, but I had the same frustrations until I intuitively grasped what resistive spotwelding actually meant.
You need a reasonable amount of resistance to current over a reasonable “spot” above the nickel and battery terminals to produce welding temps sufficient to melt those materials.
If you understand why you can’t weld pure, unplated copper to cells, then you already know, and I’m don’t mean to sound condescending,
Hakko is great and a damn good price until they randomly stop working.
Of the three Hakko stations I’ve seen (their competitor to Weller WES51), they’ve all randomly stopped heating eventually. I’m sure it’s probably a somewhat easy internal fix, but definitely annoying and easier to pay a bit more up front to not have to deal with it.
I will try pressing less. The contacts were wider and more stubby before I sharpened them and it didn’t work then. Before I began trying to push hard I was pushing lightly and I thought that was the problem. You don’t sound condescending at all and I need help so thank you
I have a very basic but somewhat confusing question. I am currently building a huge powerbank to charge multiple phones at once, 1s 28p, as I am wiring the usb converters, is it necessary to put the negative and positive connections opposite of eachother, as many do when building packs for longboards to get the full “energy range” I suppose, as seen in this picture.
The usb boards are designed to use a 1s battery, they have all the tech inside them to boost and control voltage/amperage.
The question is; is it necessary to have the connection opposite (as seen with the red ink) or is it fine to have them next to eachother(as seen with the black).
As long as all the cells are connected in parallel (top and bottom), then either way will work.
At low currents like this, it doesn’t matter at all, since current is shared between all the cells through the parallel connections.
The only time it would be better to go with opposite corners (or better yet, use a bus bar) is if you’re drawing tens of amps per cell, which can result in uneven current sharing.
You probably have already though of this, but if not I’ll mention it here:
It’s going to take approximately three to four days of continuous charging through one of those modules to completely fill the pack from empty. Of course you could speed that up by charging it through more than one at once, but if it were me, I’d look into adding a single high-current charger to the design so you don’t need to hunt down a half dozen USB ports to charge the thing back up in a timely manner.
A simple solution I’ve used in the past was an RC charger like an imax b6 or similar.
I have indeed done quick searches but to no avail for fast charging for 1s. I will look into rc chargers to find the solution. Thanks you for all of your input!
