[LG G5 Accessories] waylo:
There is a lot of ongoing work by companies to manufacture charging products for new USB Power Delivery (USB-PD) and Qualcomm Quick Charge (QC) devices. Because the USB-PD and QC specifications are at direct odds with each other, the products are difficult to standardize, leading to confusion among consumers. Essentially, anything that does not adhere to the strict USB-C specifications is considered in violation. Google Engineer Benson Leung has tested numerous USB-C cables and chargers and found many to not be within USB-C specification. This implies they may be dangerous for USB-PD devices. However, I have not seen any true proof of QC chargers damaging USB-PD devices, only that they will not fast charge them.

The engineering points are numerous and can get fairly complex, beyond the scope of this review. However, I find it important to add to the fount of knowledge with our new phones and charging devices, and this is my small contribution.

I own a LG G5 phone, and my testing and comments are limited to this device only.

My simple method is to use a USB-A multimeter as well as the Android OS’s amperage reading. There are limitations to this. Primarily, I have been informed that the Android OS amperage is based on a voltage of 5V. This was certainly fine in the days pre-Qualcomm Quick Charge, but now with higher and variable voltage, the amperage readings are not reliable. Secondly, as this is a USB-A meter, I have no way of directly monitoring USB-C amperage or voltage. Thirdly, I do not have the ability to digitally log the voltage off the multimeter, so some of the data points presented are more general than I would like.

Here I am reviewing the Tronsmart Presto 12000mAh battery pack, which has both a USB-C port for USB-PD devices (Nexus 6P, etc) and a USB-A port for QC3.0 devices (LG G5, HTC10). It is available here:

https://amazon.com/gp/product/B01GVBFBBO/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=ALTVS0Q5KJ7M3

It was provide to me for my review.

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The main selling point of this battery pack aside from the QC3.0 capability is the dual types of ports. If you happen to have both QC3.0 and USB-PD devices, this battery pack can theoretically fast charge either. The QC3.0 port is rated at the usual QC3.0 voltages/amperages, and the USB-PD port is rated at 5V/3A. It comes with a short USB-A to USB-C cable to be used with the QC3.0 port. You’ll have to supply your own double-ended USB-C cable if you want to go C to C.

There’s a 4 LED gauge for how much battery is left. During charging, the LED at the end will flash. On the side there’s a button to turn on the charging. The battery is charged through the USB-C port (it’s used both for output and input). Attached to my separate QC3.0 AC adapter, the battery charged at 2.4A / 5V only. I do not have a USB-PD charger to use to charge the Presto.

EDIT: I re-tried the charging measurements using a Tronsmart branded QC3.0 AC adapter and the battery now charged at 15W, ~2.7A and 5.6V. This is better than the prior measurements! Your charging adapter matters!

For this test, I used the included USB-A to USB-C cable for the QC3.0 port. My USB-C to C cable is one provided by ChoeTech (available here https://amazon.com/gp/product/B01H3COF62/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1)

I drained my phone down to ~20% and plugged in. Here is how the charging times for the Presto battery ports compare:

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To go from ~20 to 100% for QC3.0, it took ~70 minutes. For the USB-PD port, it took 90 minutes. The mA readings for the QC3.0 are not accurate, but those reported by the Android OS. The USB-PD amperages are likely correct.

I have previously tested several QC3.0 and QC2.0 chargers. The charging time for the QC3.0 port lines up well with my multiple previous measurements. Those show that for 0-100%, it takes ~80 minutes, with ~20% increase/10 minutes for the first 20 minutes.

For the QC3.0 port, here are some general points collected from me taking notes on the multimeter readings:

Wattage maxed out at ~16-17W. Not bad!

Voltage maxed at 8.70 very briefly. Most of the early measurements (fastest charging) were at 6.4-7.4 volts.

Amperage maxed at ~2.6 briefly.

These measurements all fall within QC3.0 guidelines.

Regarding the USB-C port readings, it seems that despite a recent Gtrusted.com review,

http://gtrusted.com/review/lg-g5-su...-to-qualcomm-quick-charge-3-0-over-usb-type-c

which reported the LG G5 is also capable of negotiating charging over the USB-PD standard, many kinks and incompatibilities remain. Gtrusted.com subsequently found that the G5 cannot charge at all from the Anker or iVoler USB-PD charger USB-C ports:

http://gtrusted.com/review/40938

http://gtrusted.com/review/40937

I did not have that issue with the Presto, but the USB-PD port charging times were suboptimal. They lagged behind QC3.0, and an additional 15-20 minutes was necessary to top off the phone. I doubt the G5 is able to extract the 5V @ 3A the port is advertised to provide for USB-PD devices and that the initial Gtrusted report suggested.

Previous to my testing, I had wondered if the G5 would get the fast charging benefits of USB-PD chargers. In this case, it does not. As I mentioned in the introduction, the standards of USB-PD and QC clash with each other. Specifically, it is very unclear how manufacturers are implementing charging through USB-C ports.

Some earlier models had put QC3.0 into USB-C ports, which is in violation of USB-PD standards. BUT, I want to point out, why and how does that even affect QC capable devices? It really doesn't. The outrage on retailers such as Amazon is driven by the USB-PD side, neglecting entirely Qualcomm’s tested standard. Manufacturers in turn are removing their QC implementation from the USB-C ports and leaving them USB-PD only.

One notable issue I discovered was with the phone after the charging finished on the USB-C port and the battery auto-shutoff. The phone made repeated connecting/disconnecting sounds despite the battery pack being off. I think this is solely a G5’s issue though--perhaps the G5 detects a USB-C device but cannot successfully interface with it. The same thing occurs when the battery pack is off and you first plug in the USB-C cable. This subsides once the battery pack is turned on.

In conclusion, having 2 fast charging solutions in one battery pack is a worthwhile luxury. It’s great to see products like this fill the need. Having full-fledged QC3.0 capabilities in a portable unit makes travel and juicing up quick, easy and convenient.

Pros:

2 different ports to charge either USB-PD or QC3.0 standards! There are few options like this these days.

QC3.0 amperage, voltages, and charging times are similar to AC QC3.0 adapters!

Auto-shutoff is a nice feature to preserve battery life.

Includes a USB-C compliant USB-A to USB-C cable, a necessary touch to charge the battery if you don't already have one

If you have a capable QC3.0 charger, the battery will charge at ~15W

Cons:

The G5 does not charge at 3A/5V with the USB-C port. My estimates suggest it is more like 5V @ 2A. This may not be any fault of the charger but rather the programming controlling the charging from the phone.

Other:

The USB-C port interface with the G5 results in repeated connects/disconnects if the battery is not off. This is more likely an issue with the phone than the Presto.

2 different ports means 2 different cables to carry!