Wasn’t aware that GearBest is forcing people to buy products with questionable quality that are not even that cheap when you think about it…
Btw, half of the cells from the list about are not suitable for application in power banks and letting equally battery uneducated folks to choose for themselves would be even worse than selling them empty shitty power bank case.
I just listing all my batteries. All protected cells don’t fit, and no point using high drain batteries. So my plan was to use Sanyo UR18650ZY (2600), Panasonic NCR18650BE (3200) or Sanyo NCR18650BF (3400).
Is that OK for you? Was thinking about a 2900 battery also, but did not want to buy 50 pcs to keep the price down, when I have so many 3200 and 3400 batteries.
I was not forced to buy them, but because of the price and all the info on the product page, with short circuit protection and all, I was sure this was a good product, that I could use, with the three mention battery types. I ordered 1 first, but it took so long time before I got it, that I had ordered 10 more.
I did buy this quality:
Nobody is forcing anyone to buy poor quality products, but nor do I expect dangerous products to be sold.
I personally would have bought a Xaomi, but I wouldnt expect any PB to catch fire.
Marc
Still don't think the problem is the power bank. It must be a combination of the battery (some bad isolation) and the spring prying through the isolation. Maybe the due to an angle when inserting the battery the spring caused it? It's to local to be something else.
Sounds like the power bank then;)
If you were to straighten the spring assembly out…how long a piece of wire do you think it would be…that last battery thru that long run…very thin gauge + long run = high voltage loss
Low voltage of battery put in very high current draw to feed the boost circuit to make 5vdc from say 3.7 or lower vdc, high current flow thru thin wire = heat
I recommend on all parallel connections thru these thin steel springs is to spring bypass with a piece of 22ga copper wire, this way the current flows thru the wire and not that low current flow type spring steel
In fact check out a test one of our awesome member here did showing the voltage loss thru springs (spring #4 looks about the same gauge)…now multiply the loss thru springs x 5-10 times due to the length from the - side to the circuitry at the board (even a full charge battery would probably surge current if it was the first battery placed in that very long high resistance run)
That kind of setup is a very very poor conductor of power…all current is parallel thru battery all concentrated in that one single run
LOL the place for cell holder says AAA but its meant for 18650 .. when will these chinese manafactures learn..
the voltage drop at .5A was 110mV from one end of the sprint to the other end on the pcb.
and these chepos arent able to output 2A .. so 2A output at 5v usb output means roughly 2.5-2.8 A draw from battery .. if there re three battires on this end then it means .5A from each battery for 5 cell bank .. and 1.5 * .1 = .15 watt