In a nutshell, what I think I know is, that lower charge current might, in the long run, be more advantageous to cell longevity than higher charge current. I also think I know that, once a threshold is reached close to full charge of a cell, transfer to a slightly different charging scheme is necessary to assure full charge but not overcharge. Finally, end-of-charge trickle charging is not particularly desirable.
I have a few orphaned wall chargers that came with Jabra and Plantronic brand Bluetooth earphones. They all have micro-USB connectors, and are all rated 5vDC at 180mA, a fairly low current.
When used to charge the original earphones, the charging indicator(s) on the earphones would change state when charging was complete. I believe that means that a charge control chip was embedded in the earphones themselves.
My question is; will using these 180mA chargers have any deleterious effects if they're used to charge LiIon cells in lights, cell phones etc. that have charge indicators built into them?
Yes because those arnt chargers, all they’ll do is apply 5v @180mA current to the battery indefinitely.
If a device has a USB plug it meets the USB standard which doesn’t include li ion charging. USB is power and data only, the device must handle charging internally. What you have is simply a 5v 180mA power supply, the ear buds have the charger controller built into them.
DO NOT attempt to charge a battery with USB cable unless you have a charger (for the correct chemistry of your battery) which happens to be powered by USB but as far as I know there arnt any currently on the market designed to accept that low of input current (there are plenty of USB li ion chargers powered by USB however most of them require a 2000mA USB cable)
Considering all the devices sporting micro-USB charging ports that come with chargers (cell phones, GPS devices, Bluetooth earphones, etc) and that some flashlights and even cells have micro-USB sockets for charging, am I to believe that none of them have any kind of charge control chip built into them?
Seems counterintuitive.
EDIT: Perhaps the very low current of 180mA is the problem? If a charger with an output capacity of 1A was used instead, would that be appropriate?
If you’re charging a device that has a Micro USB charge port and contains Li-Ion batteries, then your Bluetooth “charger” will be fine. The device itself has the actual charging circuit built in.
I think you’re talking about Li-Ion cell chargers, like the Nitecore D4 or the Lii-500? I don’t think that’s what the OP is talking about. But I could be wrong.
Thanks for the reply. That's exactly what I talking about.
To put a finer point on it, can I assume that when using the 180mA charger, the charge will terminate approximately correctly? Or is the supply current of 180mA too low for correct sensing in devices with higher-capacity cells (smart phones, GPS devices etc.)?
That would surely be a factor in whether the 180mA supply will work for your purpose or not. Perhaps someone who knows will come along and help you out.
If the device tries to draw more than 180mA, then your charger will either overheat or shut itself down due to the overload. The Li-Ion cell in the device should be fine, it’s just the charger that might have problems. If you try it, keep an eye on the charger and device until you’re sure it’s working safely and correctly.
Some devices (e.g. my Samsung tablet) will adjust the current they draw to avoid overloading the charger, but other devices (e.g. my EasyAcc powerbank) will try to suck out every mA they can get, even if it overloads the charger. It’s a bit of a lottery.
