Avoiding "slow charging" message
Originally Posted by gwbyrd
I stopped by my local Microcenter computer superstore tonight and picked up a generic $7.99 dual USB car charger that does 1x2A or 2x1A. I used the OEM cable that came with my phone and it gives a charge of approximately 30-36% per hour with no "slow charging" message.
So, at least in my experience, I can confirm that generic 2A car chargers work with the correct USB cable.
However, I took an old USB cable and modded it to short out the data cables on the phone side and left the data cables unconnected on the USB side, and I am getting the message that it is not compatible on any charger that I try. I was pretty careful to make sure I connected the correct wires, taped them up, etc. I used the following diagram:
So, I know I can use generic 2A chargers, but I'm still struggling to find a working USB cable. Does anyone else know of any confirmed working non-OEM charging USB cables?
It looks to me to not get the "slow charging" notification you need either a charger or cable that shorts the data pins, a charger capable of putting out more than 1A (how much more I don't know--my 2013 Nexus 7 charger works with the stock G2 cable and it's 1.35A), AND a cable that avoids a significant voltage drop (the stock G2 cable has 20AWG conductors and it's the only one I can reliably get to work with every charger that meets the first two specs). I'm guessing the G2 is testing both voltage and current to determine charge speed, and displays the message when either are out of spec 500mA will still charge the phone just fine if it's off or idle, the challenge for me is the car challenge--using my device for navigation and music, I need to get a full 10 watts to the device to ensure it says charged on a long road trip. I don't know if the G2 is more sensitive than other phones or it's just telling us something that other phones didn't.
I haven't found a source of 28AWG/20AWG microUSB cables. You could buy the LG OEM charger and cable, but the cable is only 3ft (I would think a 6ft 20AWG charge cable would still work but it might not.)
I have some of the Mediabridge charge cable converters (USB pigtails that short the data pins) and they will make my stock cable (or other cables that happen to work) say "slow charging." I suspect this is because they have 24AWG charge conductors, and the added resistance of the two extra connectors in the link.
Ideally I'd get a bunch of 20AWG charge conductor cables, short the data leads, and 2.1A chargers wherever I need them (home, work, car, travel.)
Also worth noting I'm using CurrentWidget and you'll rarely see it over 1000mA when the phone isn't saying "slow charging" because either because the phone is using current instead of charging the battery or the charging circuitry is dropping to trickle mode to top off. Again, getting max current out of the charger is for when the phone is drawing significant current while running and still have enough left over to top off the battery.