A few questions about chargers/cables....?

I know it's been said that you should always use the charger that comes with your device to charge it however sometimes circumstances can dictate the need to use other means to charge your device.

I have a few questions in regards to this.

1 --- Sometimes my phone will say CHARGING USB and other times it will say CHARGING AC. Is this a certain voltage that is needed to reach the phone which accounts for this distinction? I know when I use different cables (even with the same charger) it will display USB at times even when I'm not charging it via USB.

2 --- How much longer (in general) will the charge take if it says charging USB compared to AC? Will it take twice as long? Longer? I've always been curious about this.

3 --- Do they make "higher end" cables, perhaps like a "monster" type cable with maybe gold plated connectors or a cable with lower "loss" characteristics? Is it worth the extra investment because I get most of my cables on the cheap.

Thank you

DAVID

 

I dont have much electrical knowledge, but I think generally for charging phones it should be, ac in dc out. You plug your charger into the wall outlet(ac) and it gets converted to regulated dc, which you charge your phone with.
On the charger it should say how many volts are needed for your phone. Look for DC and there should be a number like 5.5V or something like that.
Have you noticed it taking a slower charging time when it says usb?
They probably do make cables like that, but generally the most important thing is the charger itself. You can have the best cable, but a lame/bad charger, and that won't be any good.
I'd get get a charger that had similar volts to the original manufactured one, or one that is better.

 

1. My phone doesn't distinguish between charging via USB, the wall charger or a charger in my car. Mine just says charging.

2.

That's not easy to determine. It depends on the charger with the device. (I have 3 android devices and the chargers are all different. volts, amps and watts are all different). It also depends on the % of the battery. The higher remaining, the less time to charge.
USB charging through a computer will always be slower than using USB with the wall charger.

3. Cables are cables. I must have 7 or 8 USB/micro USB cables and I haven't noticed a difference.

I've never tested if shorter cables charge faster. I prefer longer cables so I can set the device conveniently on a desk or table and not hang near the wall plug.

The charger should have the same volts, not similar and not more than the original.
Two of my devices use 5V chargers and the other uses a 5.2V charger. I won't use the 5.2V on the devices that require 5V. From reading, it can damage the charging circuitry. I'm not willing to take the chance to find out if this is true.