Disclaimer, I'm not a USB expert myself, but I have read extensively about Volt and Ampere outputs in the process of researching which brand of multiport car ciggy lighter gives the most bang (charging rate) for my buck ($$$) in fast charging

Google extremetech.com and androidexchange for further information.

In a nutshell, to answer your questions, (based on expert or user opinions on these websites):

In general, there are two key factors that affect how quickly your device charges over USB: (1) The maximum amperage of the USB socket, powerbank or wall charger, and (2) how your device negotiates power delivery from the socket/charger.

As for (1), Not all USB chargers, connectors, and cables are born equal.

For a start, every charger or socket has a max amperage — usually between 500 milliamps (mA) and 1.5 amps (A). In general, unless it says otherwise, your laptop and PC are probably outfitted with 500mA sockets (unless they’re USB 3.0, in which case they’re probably 900mA). Specifically, USB 2.0, in terms of actual current (milliamps or mA), there are three kinds of USB port dictated by the current specs: a standard downstream port, a charging downstream port, and a dedicated charging port. In the USB 1.0 and 2.0 specs, a standard downstream port is capable of delivering up to 500mA (0.5A); in USB 3.0, it moves up to 900mA (0.9A). The charging downstream and dedicated charging ports provide up to 1500mA (1.5A). There is also USB chargers that provides 2.1A at 5V.

For [B]cables and connectors, the inside pins carry data (D+ and D-), and the outside D- (date minus) pins provide a 5-volt power supply. You've heard of Apple usb cables that melt and burn? V = IR, the cables are not rated to handle the high 2.1A at 5V

The longer answer is that the age of your device plays an important role, dictating both how fast it can be charged, and whether it can be charged using a wall charger at all

In 2007, USB Implementers Forum released the Battery Charging Specification, which standardized faster ways of charging USB devices, either by pumping more amps through your PC’s USB ports, or by using a wall charger. USB devices post 2007 should follow this spec. Modern devices with this spec can be pluged into a high-amperage USB port and enjoy faster charging. On the other hand, if you have an older device, however, it probably won’t work with USB ports that employ the Battery Charging Specification; it might only work with old school, original (500mA) USB 1.0 and 2.0 PC ports

As for (2),
The max amperage dictates one thing only: The max theoretical charging rate of your device. It is through negotiation that your device actually decides how much power it wants to draw from your power source, e.g. powerbank. When you plug your device into a charging socket or wall charger, the USB controller in your device talks to the USB controller attached to the socket/wall charger — or, if no controller is available, the device reads the voltage flowing across the four USB pins. From this data, your device decides how much amperage to draw, and thus how quickly it will recharge.


Hope this is informative enough,
newbie alert, forgive me if I did not follow forum conventions

when2meets2boy

This post has been edited by when2meets2boy: Oct 18 2015, 04:50 PM

Dear all, I need suggestions, what use do I have with salvaged 18650 type batteries recovered from powerbanks?

Reasons are simple, I have a Pineng model PN-913 10,000mAh that died one day over the 1 year warranty period. I contacted Pineng.com.my, but there's no reply, I suppose that since it's over the warranty period, they have no obligations to service the warranty

That aside, I am very certain the 18650 type batteries inside the PN-913 are alive and kicking, this much I know because it was working a wonder prior to the 'incident',

I reckon I shorted and fried the IC controller inside the powerbank while exploring the possibility of a Xiaomi powerbank charging the Pineng. Never mind what went wrong there, possibilities: it could be Xiaomi shorting Pineng, or the Xiaomi - USB Current Voltage Meter Tester - Pineng combo shorting Pineng (perhaps Pineng couldn't negotiate with Xiaomi through the meter tester), or just simply, Xiaomi doesn't like Pineng.

I reasoned that I shouldn't let the 18650 type batteries waste away, or worse, leak its toxic contents after the battery casing deteriorates over time. I already found a part of the solution, i.e. I can still charge them via gadgets like Nitecore D4 Universal Rechargers,

TO all, I want to ask if anyone has come across a battery-adapter/controller for the 18650 type batteries that will enable me to control the output voltage (V) and current (aMh). I am planning to jig it up with my GoalZero setup, in case a zombie apocalypse strikes or the Red Shirts get's their way at messing up our country

Thanks in advance.

PS> It's sad Malaysia doesn't have a policy that recover and recycle batteries (all batteries are toxic if it leaks). Malaysians just throw it in the bin, that is so so so bad

This post has been edited by when2meets2boy: Oct 18 2015, 07:20 PM

Thanks. I've got a whole 45 L plastic container filled of discarded batteries to be recycled, it's been 30 years I've been using batteries,and finally we seem to have a national program (Anyway, I'll wait and see, I'm in KL and no one else seems to be doing it). I'll see how this pilot program goes, the old adage goes, in Malaysia, bright ideas, bad implementation.

LAZADA is vcool! Found some potential fun and funky "solutions" to re-use the recovered 18650s from the Pineng teardown.
Examples, Chilli , Red Chillis, or Bananas, or if you are of the more serious type, get this kit, 5V 1A 3x 18650 Battery USB Charger Box Kit Mobile Power Bank

Or get security torches that usually uses 18650s