Ahh didn’t realize the cell difference, guess I should read more lol. But these appear to just pop out based on the photos.
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Ya those are the ones I got but I bet they’re welded
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So these batteries are draining a little, the black is the voltages on 7/3 and the green were taken today. Seems to have drained around .01V. Are these cells toast?
Do cells drain faster at higher voltages BTW?
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Higher voltage cells will drain at a faster rate, as the battery drains it chips away at the mAh of the cell, that current is equal to voltage * resistance so for cells of a given resistance the highest voltage cell will loose capacity faster. However if the resistance is the same it will never drain any lower than the originally lower voltage cell
But also cells that drain more than 4 hour after charging are sketchy at best anyways
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Hmmm I suppose I won’t know for sure then until I charge some to 3.7 and let them sit.
I charge them all to 4.2V then wait a day, then charge time back to 4.2V at really low current which makes sure all have the exact same charge and it’s chemically balanced, then I let them sit for a week and toss all the ones that as re 4.17 or less
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Ahhh interesting, sadly my charger doesn’t have the ability to adjust charging rate. Poop.
$20 prime on amazon for a quad bay charger…
Really? Do you have a link?
The price seems to have gone up, this is the one I own and its not spectacular but it gets the job done with not too much hassle. It does like to reset the charge current all the time though and the capacity feature is only accurate to an order of magnitude
https://www.amazon.com/18650-Universal-Automatic-Rechargeable-Protection/dp/B07H32WVTF/ref=sr_1_3_sspa?dchild=1&keywords=quad+bay+charger+18650+miboxer&qid=1594421559&sr=8-3-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyWjVBSVUzMlMxRVFQJmVuY3J5cHRlZElkPUEwNzY3NDk1MjFMNjk0S0g3NEk5VCZlbmNyeXB0ZWRBZElkPUEwODk4Nzk2MzlWSVk2QVdLMVQ1QyZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
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word. I ended up getting the 8 bay verion of the same thing, price comes to about $24/4cells so works out
https://www.amazon.com/gp/product/B07QXP6XT3/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
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I have the same 8 way one. Works great
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I’d say the welds look good, but you need to work on your consistency of weld placement, and your nickel ends. While rounded, they are far from being symmetric or clean looking.
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Are you using guides or is that all free hand? The placement is scattered but the welding current and pressure looks good, maybe tone it back a couple joules and keep the pressure more consistent but it looks decent
I’d get a bunch of scrap cells together and start doing more practice, weld over the same dead cells until you feel better about it. If you don’t have scrap cells you can use a razor blade (but that’s cheating because it’s a lot easier) or I’ll send you a handful
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I’m not really sure how to line them up well. Maybe I’m just blli d =/
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Practice makes perfect
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You could mark a reference, like a toothpick taped down and you push the electrodes up to it
Also what Al says, that’s the big one
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A couple micro-point sharpie marks for reference will help, or maybe pencil.
Ideally what I’d want to see are nice straight rows of welds all consistently spaced, like this.
(Not my own battery. Stole it from google images.)
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When I first started my welds were a bit all over the shop too. It just takes time and practice to get used to using the probes and honing the technique.
Also, if you are using a probe holder, throw it in the bin. They don’t help IMO.
At the end of the day tho, as long as the welds are good and strong, thats all that matters.
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