Batteries not included: USB Power Delivery is the fastest way to charge iPhone and Android devices
Last Updated on by Segun Ayo
With the current generation of smartphones with their much faster processors and vivid, high-resolution displays and always-on connectivity, demands on battery performance are now higher than ever before.
You may have noticed that while you are on the road, you’re running out of juice quickly. If you have this problem, portable batteries, and faster wall chargers are your solutions.
But not all portable batteries are the same, even though they might use similar Lithium Polymer (LiPo) and Lithium-Ion (Lion) cells for capacity and look very much alike.
Modern smartphone hardware from Apple and various Android manufacturers support faster-charging rates than what was previously supported.
But if you use the charger that comes in the box with the current generation iPhone hardware, or if you buy just any portable battery pack on the market, you’re going to be disappointed.
Ideally, you want to match your charger, battery, and even the charging cable to the optimal charging speeds that your device supports.
There are three different high-speed USB charging standards currently on the market. While all of them will work with your device using a standard legacy charge mode, you will ideally want to match up the right technology to optimize the speed in which you can top off your phone, tablet, or even your laptop.
Let’s start by explaining the differences between them.
Legacy USB-A 2.0 and 3.0 charging
If your Android device or accessory still has the USB Micro B connector (the dreaded fragile trapezoid that’s impossible to connect in the dark), you can fast-charge it using an inexpensive USB-A to USB Micro B cable.
If the device and the charger port both support the USB 2.0 standard (pretty much the least common denominator these days for entry-level Android smartphones), you can charge it at 1.5A/5V.
Some consumer electronics, such as higher-end vape batteries that use the Evolv DNA chipset, can charge at 2A.
A USB 3.0/3.1 charge port on one of these batteries can supply 3.0A/5V if the device supports it.
If you are charging an accessory, such as an inexpensive pair of wireless earbuds or another Bluetooth device, and it doesn’t support either of the USB-A fast charging specs, it will slow charge at either 500mA or 900mA which is about the same you can expect from directly connecting it to most PCs.
|USB PD||Variable up to 20V||5A||USB-C|
|USB Type-C 3A||5V||3.0A||USB-C|
|USB Type-C 1.5A||5V||1.5A||USB-C|
|QC 4.0 (USB-PD Compatible)||Variable up to 20V||4.6A||USB-C|
|QC 3.0||Variable up to 20V||4.6A||USB-A/USB-C|
|QC 2.0||5V, 9V, 12V, 20V||2A||USB-A|
|USB FC 1.2||5V||1.5A||USB-A|
Many of the portable batteries on the market have both USB-C and multiple USB-A ports. Some of them have USB-A ports which can deliver the same voltage, while others feature one fast (2.4A) and one slow (1A).
So you will want to make sure you plug the device into the battery port, which can charge it at the fastest rate if you’re going to top off the device as quickly as possible.
USB Power Delivery
USB Power Delivery (USB PD) is a relatively new fast charge standard that was introduced by the USB Implementers Forum, the creators of the USB standard.
It is an industry-standard open specification that provides high-speed charging with variable voltage up to 20V using intelligent device negotiation up to 5A at 100W.
It scales up from smartphones to notebook computers provided they use a USB-C connector and a USB-C power controller on the client and host.
Batteries and wall chargers that employ USB PD can charge devices up to 100W output using a USB-C connector — however, most output at 30W because that is on the upper range of what most smartphones and tablets can handle. In contrast, laptops require adapters and batteries that can output at a higher wattage.
Apple introduced USB PD charging with iOS devices with the launch of the 2015 iPad Pro 12.9″ and with OS X laptops in the MacBook Pro as of 2016. Apple’s smartphones beginning with the iPhone 8 can rapidly charge with USB PD using any USB PD charging accessory — you don’t have to use Apple’s OEM USB-C 29W or its 61W power adapters.
In 2019, Apple released an 18W USB-C Power Adapter which comes with the iPhone 11 Pro and 11 Pro Max. Although Apple’s charger works just fine, you’ll probably want to consider a third-party wall charger for the regular iPhone 11 or an earlier model.
Fast-charging an iPhone requires the use of a USB-C to Lightning cable, which until 2019, needed Apple’s OEM MKQ42AM/A (1m ) or MD818ZM/A (2m) USB-C to Lightning cables which unfortunately are a tad expensive at around $19-$35 from various online retailers such as Amazon.
There are cheaper 3rd-party USB-C to Lightning cables. I am currently partial to USB-C to Lightning cables from Anker, which are highly durable and are MFI-certified for use with Apple’s devices.
It should be noted that if you intend to use your smartphone with either Apple’s CarPlay and Google’s Android Auto, your vehicle will probably still require a USB-A to USB-C or a USB-A to Lightning cable if it doesn’t support these screen projection technologies wirelessly. You can’t fast-charge with either of these types of cables in most cars, and there is no way to pass-through a fast charge to a 12V USB PD accessory while being connected to a data cable, either.
Qualcomm Quick Charge
Qualcomm, whose Snapdragon SoCs are used in many popular smartphones and tablets, has its fast-charging standard, Quick Charge, which has been through multiple iterations.
The current implementation is Quick Charge 4.0, which is backward-compatible with older Quick Charge accessories and devices. Unlike USB PD, Quick Charge 2.0 and 3.0 can be delivered using the USB-A connector. Quick Charge 4.0 is exclusive to USB-C.
Quick Charge 4.0 is only present in phones which use the Qualcomm Snapdragon 8xx, which is present in many North American tier 1 OEM Android devices made by Samsung, LG, Motorola, OnePlus, ZTE, and Google.
The Xiaomi, ZTE Nubia and the Sony Xperia devices also use QC 4.0, but they aren’t sold in the US market currently. Huawei’s phones utilize their own Kirin 970/980/990 chips, which use their own Supercharge standard, but they are backward compatible with the 18W USB PD standard.
Like USB PD, QC 3.0 and QC 4.0 are variable voltage technologies and will intelligently ramp up your device for optimal charging speeds and safety. However, Quick Charge 3.0 and 4.0 differ from USB PD in that it has some additional features for thermal management and voltage stepping with the Snapdragon 820/821/835/845/855 to optimize for reduced heat footprint while charging.
It also uses a different variable voltage selection and negotiation protocol than USB PD, which Qualcomm advertises as better/safer for its own SoCs.
And for devices that use Qualcomm’s current chipsets, Quick Charge 4.0 is about 25% faster than Quick Charge 3.0. The company advertises five hours of usage time on the device for five minutes of charge time.
However, while it is present in (some of ) the wall chargers that ship with the devices themselves, and a few 3rd-party solutions, Quick Charge 4 is not in any battery products yet. The reason for this is that it is not just competing with USB Power Delivery, it is also compatible with USB Power Delivery.
Qualcomm’s technology and ICs have to be licensed at considerable additional expense to the OEMs, whereas USB PD is an open standard.
If you compound this with the fact that Google itself is recommending OEMs conform to USB PD over Quick Charge for Android-based products, it sounds like USB PD is the way to go, right?
Well, sort of. If you have a Quick Charge 3.0 device, definitely get a Quick Charge 3.0 battery. But if you have a Quick Charge 4.0 device or an iOS device, get at USB PD battery for now.
Now that you understand the fundamental charging technologies, which battery should you buy? When the first version of this article was released in 2018, the product selection on the market was much more limited — there are now dozens of vendors currently manufacturing USB PD products. Still, ZDNet recommends the following brands and models:
Anker (One of the largest Chinese manufacturers of Apple-certified accessories)
RavPower (Similar to Anker, typically more price competitive)
ZMI (Accessories ODM for Xiaomi, one of China’s largest smartphone manufacturers)
Aukey (Large Chinese accessories manufacturer, value pricing)
Mophie (Premium construction, Apple Store OEM accessory)
Zendure (High-end, ruggedized construction, high output ports)
Goalzero (Similar to Zendure)
OmniCharge (High-end, enterprise, vertical-industry targeted, advanced metering and power flow control)
Which wall/desktop charger?
As with the batteries, there are many vendors providing USB PD wall charging accessories. Gallium Nitride (GaN) technology, in particular, is something you should stronger consider in a wall charger if you are looking for maximum space efficiency in your travel bag and for power output. ZDNet recommends the following brands and products.