I’ve covered a bit of the Qualcomm Quick Charge 2.0 chargers, which can get you charge rates that are pretty astounding when compared to things we had three or four years ago. But even if your device charges some other fashion (non QC2,) there’re still some free things you can do to speed the phone’s charge up even more.
TL;DR: Paul’s been going on about a really long test in charge methods, came up with a couple of ways to charge faster without damaging your phone. Just move the heat off of the phone while you’re charging it.
Your primary slowdown on quickly charging a phone when you’ve got a good charger usually is heat. Once the battery gets too hot the system will pull back the juice it’s drawing. This is to prevent the phone from overheating the battery, causing it to rupture, and in a bizarre fluke accident turning you into the somewhat scarred superhero known as Battery Acid Man.
Mostly it prevents the battery from damage.
You’ll see this evidenced in apps like Battery Monitor Widget as a large block of charge with the temperature steadily going up and at a certain point it drops the amazing charge and goes to something that while positive, isn’t what you paid for a better charger for. Once the heat goes down to a certain point and sticks there the fast charging resumes at better rates.
So your first step if you need a charge in a hurry is to get the heat that’s being generated by the battery off of the phone. This will enable it to charge at the optimum rate without the governor kicking in and slowing down the charge.
For my HTC One M9, I found laying it face-down dispelled more heat, as did aiming a fan at it (obviously). The results were longer periods of +2400mA or better blocks of charging. packing the unit in ice cold gel wraps didn’t seem to help at all, it actually ramped down to +200mA shortly after chilling, so my guess is there’s a specific temperature range you need to keep it in.
Getting as much airflow on a unit helped the most. Putting the phone on a couple of quarters so there was no ground heat-sink effect, letting the phone breathe, that seemed to be perfect and kept the fast charging going for a really long time.
Depending on your phone, turning it off might also help. As most of the modern phones are technically on all the time even when they’re off, the only increase in speed would be the minor amount you’re using during a charge and perhaps contributing less to the heat situation.
In the car I just put my phone charge port up in a cupholder and that seems to do a much better job than sitting it in the car seat. Holding it in from of the AC vent just leaves me thinking that something has gone terribly wrong in my adult life to lead to this. It does, however, cause the unit to charge a little bit faster.
While the above will help with the heat, I found the biggest benefit to charging seemed to not be waking the screen up for any reason. At least on my setup it appeared every time the screen came on (notifications, incoming calls,) the phone would forget about fast charging and drop to normal.
Alternately skip all of that and just carry portable phone chargers. I used to all the time, but with the ability to charge the phone in an hour I rarely keep them around. With quick charge 2.0 and standard 2.4amp chargers for between $5 and $20 for both wall and car outlets, the appeal of carrying portable power all the time has waned a bit.