AUKEY PB-Y13 10000 USB-C PD with iPhone 8

Fast Charging iPhones with USB-C

Phone battery life has not improved at the same rate as other features. Having an extra charger at work or a power bank in your bag is handy. You can fast charge newer model iPhones by using USB-C Power Delivery chargers.

The USB charger included with the iPhone supports 5W. Wireless (Qi) chargers support 5-7.5W. With a USB-C Power Delivery charger and USB-C to Lightning cable you can fast charge an iPhone at 9W or more. That’s 45% faster than the included USB charger.

Fast Charging iPhones

Fast charging standards work by increasing the voltage or current into your iPhone. Beyond what a regular USB charger can do. This gets the battery to 70% much faster. After that fast charging steps down and it takes longer to get from 70-100%.

USB Power Delivery

USB Power Delivery (USB PD) is the fast charging standard Apple uses with newer model iPhones. It is an open standard created by the USB Implementors Forum (USB-IF). They maintain the specifications of USB. Apple is one of the founding members.

In general USB PD can supply USB-C devices with 15-100W. Enough to charge a phone or power a large gaming laptop. Not all USB-C devices support USB PD.

For newer iPhones it offers up to 15W (9V/1.67A). The USB charger included with the iPhone only offers up to 5W (5V/1A). A USB-C to Lightning cable is required to use USB PD from a USB-C charger.

These iPhone models can fast charge using USB Power Delivery and a USB-C to Lightning cable:

  • iPhone 8
  • iPhone 8 Plus
  • iPhone X
  • iPhone XR
  • iPhone XS
Apple 2.4A

Apple 2.4A is an older fast charging standard which is still supported by current model iPhones. Apple developed the standard for the iPad.

Today both USB-C and USB-A chargers can offer the standard. Most USB-C ports that support it also support USB PD. In which case USB PD is used for fast charging newer iPhones. USB-A ports supporting Apple 2.4A can offer a similar level of fast charging. Note that just because a port offers 5V/2.4A doesn’t mean it supports Apple 2.4A.

For newer iPhones Apple 2.4A offers up to 10.5W. That is less than USB PD’s max 15W when used with iPhones. But the difference between the two standards narrows as the phone charges. USB PD is ~3-4W faster from 0-30%. That gap narrows as you approach 50%. And by 70% both are normal charging the iPhone.

These iPhone models can fast charge using Apple 2.4A and a regular Lightning cable:

  • iPhone 4 series
  • iPhone 5 series
  • iPhone 6 series
  • iPhone SE
  • iPhone 7 series
  • iPhone 8 series
  • iPhone X
  • iPhone XR
  • iPhone XS

Learn more about USB Fast Charging Standards.

These are the chargers I recommend for fast charging the iPhone.

A USB-C PD charger offering 18W or more will usually fast charge an iPhone. If you have other, larger USB-C devices to charge consider a USB-C charger which supports your largest device.

Anker PowerPort PD 1

AUKEY PA-Y18 18W PD plugged in


AUKEY PA-Y18 18W PD Wall Charger | Review

ZMI PowerPlug Turbo | Review

  • 45W USB-C PD
  • Larger and more output than a phone needs, but cheaper than smaller 18W options
  • Includes a USB-C to USB-C cable

Recommended Power Banks for iPhones

These are the power banks I recommend for fast charging the iPhone.

I’m only recommending up to 10,000mAh power banks. If you need 20,000mAh or more capacity there are suitable power banks available. A USB-C PD power bank offering 18W or more will usually fast charge. If you have other, larger USB-C devices to charge on the go consider a USB-C power bank which supports your largest device.

NOVOO PowerCube Mini 5000 | Review

  • 18W USB-C PD & Quick Charge 3.0
  • 5,000mAh
  • Among the smallest USB-C PD power banks on the market
  • Requires a separate USB-C to USB-C cable
AUKEY PB-Y13 10000 USB-C PD with iPhone 8

AUKEY PB-Y13 10000 USB-C PD with iPhone 8

AUKEY PB-Y13 10000 USB-C PD | Review

  • 18W USB-C PD & Quick Charge 3.0
  • 10,000mAh
  • Similar shape as your phone, easy to hold both together while charging and using
  • Requires a separate USB-C to USB-C cable

NOVOO PowerCube Mini 10000 | Review

  • 18W USB-C PD & Quick Charge 3.0
  • 10,000mAh
  • Vertical design, lighter than its peers
  • Requires a separate USB-C to USB-C cable

Fast Chargers & Battery Life

You may have read that fast charging a will reduce the battery life. There is some truth to that. But all things considered it isn’t worth worrying about.

How Lithium Batteries Charge

Fast charging operates at higher wattages, often with higher voltages. More watts mean more heat. But modern device design has this in mind. And Lithium batteries recharge in steps, which is different than older types of batteries.

  • Step 1: Constant current is applied, but capacity lags. It is like stretching a rubber band and waiting. The energy (capacity) will catch up after a lag.
  • Step 2: Current drops off and capacity increases. The rubber band has been released and the energy absorbed.
  • Step 3: Current stops as the battery is charged and ready for use.
  • Step 4: Charging goes into standby mode. It will top off the battery as needed, using low current.

Fast chargers operate in Step 1. They put as much power into the battery before it reaches peak voltage. As such fast chargers do most of their work before the battery reaches 50%. As the charge progresses into Step 2 the total output continues to reduce. By 70-80% fast charging has stopped. Step 3 and 4 never see fast charging output.

Step 1 is the least damaging period for a charging battery. Not as much waste heat is generated as there is lots of capacity to fill. Where heat can be generated is in Step 2 by using high output voltage. But that is the step where fast charging drops off and ends, taking high output voltage with it.

The phone itself controls the power brought into its battery. Chargers do not push power, devices draw it. There are voltage and temperature sensors which work with the charge control circuit. If things get too hot the phone reduces or stops its power draw.

You can read more on how lithium batteries charger here.

Low Cost Battery Replacement

A lithium battery can be configured to maximize battery life at the cost of capacity. But this has to be done by the device manufacturer, the end user can’t make the change. Consumer device makers opt for more capacity (more operational time). For most this provides a better user experience. And the battery or device can always be replaced (more money for the manufacturer).

Replacing the battery is a 2-3 year old smartphone is inexpensive. Android phones vary, but the batteries are usually $10 or less plus the cost of labor. Any phone repair shop should be able to handle the replacement and give you a quote.

Consider how much time you’ll spend trying to maximize your phone’s battery life. Now compare that to how many hours of work it takes to earn $50. Over the course of 2-3 years you’re better off replacing the battery.

Easy Steps for Better Battery Life

If you want to be proactive these are easy, reasonable things you can do to get a bit more life out of your battery.

  • Charge the phone more often. More frequent, shallower charges are better than less frequent, deeper charger.
  • Sleep or turn off the phone during charging. Placing it face down keeps it from waking up due to camera detection.
  • Charge at moderate temperatures. Never charge at freezing temperatures.