Charging Li-ions WITH BUILT-IN USB in a regular charger?

sween1911

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I can't find a reference and answer to this exact question... Can you charge Lithium Ion batteries that have a built in USB port by sticking them in a standard bay-type charger? Any concerns or exceptions?

I have 4 Streamlight-branded onboard USB 18650's that I keep exclusively for my Protac HL 5X. I always charge them with USB cables but I'd like to stick em all in a charger.
 
I only have few such cells, but never had issues charging them in a regular charger. There is a remote possibility that some may not charge, the only way to know for sure is to try.
With all the warnings and CYA lawyer talk that all manufactures put on their product labels and instructions, if it was not comparable with external chargers it would be printed in big red letters, likely in several places, including the cell wrapper
 
I can't find a reference and answer to this exact question... Can you charge Lithium Ion batteries that have a built in USB port by sticking them in a standard bay-type charger? Any concerns or exceptions?

I have 4 Streamlight-branded onboard USB 18650's that I keep exclusively for my Protac HL 5X. I always charge them with USB cables but I'd like to stick em all in a charger.
I've not run across any lithium ion cells w/ USB integral charging that don't fully support use of a standalone charger. As for my Streamlight 18650s specifically (and Fenix, Nitecore and others as well), they've always been charged w/ a standalone charger. SL essentially states this, although they reference their own standalone chargers for liability limitation against 'junk chargers' (and stupid people), of which there are plenty out there, which is understandable.

"Built-in Micro-USB input charges from Streamlight AC/USB adapters and most other USB sources. Battery pack can also be charged using the Streamlight® 2 unit Li-Ion USB Battery Charger or the Streamlight® 8 unit Li-Ion Battery Bank Charger."

Fenix states compatibility w/ their chargers as well, and this note also implies acceptability of standalone charging in general:
  • Charging Current: by charger: 800mA recommended, 4A maximum -- by USB-C port: 1.5A

I've used USB only to test the function (which works fine, albeit a bit slow, which is as expected), but do keep such cells in several sizes for mobile / travel use.
 
18650s and 21700s should not have issues. The USB rechargeable lithium ion AAs and AAAs that put out 1.5 volts need to be usb charged because the voltage changes at the + and - terminals to match alkaline battery devices. Charging them with a lithium ion charger will fry the circuitry.
 
You most likely wont fry anything, a dedicated 1.5v li ion cells chargers' output 5v, even lower than 4.2 of 3.7v li ion cells. It simply wont charge those AA AAA cells, but it should not fry anything.
 

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