Batteries with usb charging ports?


Newly Enlightened
Aug 21, 2023
Yea that feature is very handy of that headlamp! But I meant it more of a quality wise standpoint. Does internal resistance say anything about quality?

Yea the manual says button top but it works with a flat top as well. Also I thought most cells have 8A 3,6V/3,7V.
What would you say would be a good protected cell for that headlamp? ( Nitecore cells are too expensive).

Also, with the "lgabhg21865 " cell i got about 40% of my phone full. It Stopped charging at 3,54V.

Why are there really compact power-banks that seem to have a better capacity even tho they are nearly as small as a 18650 cell? I thought its a good idea to use my 18650 cells as a power bank...

Edit: I just read that only 2/3 of the capacity will effectively be used. So my LG cell with 3000mAh will provide roughly 2000mAh. 40% of my 4500mAh phone cell is 1800mAh. So it'a kinda on the spectrum, I guess. Although not the best performance.
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Flashlight Enthusiast
Feb 8, 2007

If you have a usb c port on one of those huge 46800 or bigger that fine because there are no chargers for it to fit.
On an 18650 or even 21700, just get bare cell & a simple charger. The added length can be a problem & more *moving parts* to possibly fail.
(multi bay chargers convert to dc, so you can power them many different ways)

*figuratively speaking


Flashlight Enthusiast
Apr 19, 2005
chargers are good for 18650 or 21700, or 26650, but for 1,5V li ion those chargers do not work, you either need a special charger, or use those usb tails, if a cell has the port. so far no one makes a charger that works with 3.7v li ion and 1,5v li ions, As far as multiple usb tails, the more cells you put on 1 usb cable, the slower they will charge, they will be sharing the current, and the way those tails are made, (thin, high resistance wires), things will get slow.