Good article on fast charging

[BUDFORCE]

https://www.digitaltrends.com/mobile/how-does-fast-charging-work/

Even more to it than I thought.

Explains why the Mrs Moto Z2 play charges so fast with a USB-C PD charger I bought, it is insane how fast that phone charges.

Seems my Huawei P20 lite uses a different standard which is a bit slower.

So much for thinking all phones on USB-C charge at the same rate.

Also crazy how much of a minefield it is with 3rd party chargers/cables.

The industry really does need to start standardising things.

 

[Hawkesbury]

interesting read - Some of those speeds seem mega - I wonder how fast things can actually get

 

[Orcvader]

At least when QC 4.0 chargers will be released they will be compatible with both USB-PD and QC devices. Shame no one has made any and only Razer has a QC 4.0 compatible phone.

The others are a mess and seem very unlikely to match other standards...

OP's OP6 port seems to be USB 2 only as well, meaning their charging tech may not be compatible with USB 3/3.1.

 

[BUDFORCE]

Yea seems some phones are more fussy than others, my old nexus 5x charged really fast on the OEM charger, however on a QC 3.0 charger it wouldn't, even though technically the charger could output the correct v/a.

I got a USB- PD charger and that worked.

However the Mrs phone will fast charge both from a QC 3.0 charger and a USB-PD, and actually Moto have their own standard, yet it is still compatible with all 3.

I'm trying to look into what standard this Huawei P20 lite uses but it's a little more ambiguous, I've been searching and cannot seem to find anything concrete although it seems to mirror Samsung's.

I have tried this phone with a QC 3.0 and it did display "fast charging" but have not properly tested it with acubattery. I will try the USB-PD charger when I get home tomorrow also and see what that does.

 

[kona786]

I'm glad there are some OEM's out there incorporating QC 4+

https://www.gsmarena.com/qualcomm_a...xiaomi_mi_8_will_support_qc_40-news-31279.php

 

[BUDFORCE]

Yea although that QC 4.0 only tops at 18w, that isn't any faster than quite a few others already out there, only 3w faster than my 2 year old nexus 5x had.

If that article is accurate.

 

[PaulCa]

I gave it a quick read, but he fact it fails to mention the QC protocols and that it gets the details about how lithium batteries are actually charged completely wrong I decided it wasn't worth reading.

There is of course the text book answers and then there is reality.

My MotoG5+ is very picky. If I give it a basic regulated 5V which may or may not droop a little it will only pull about 0.25 amps. if I give it a much more stable 5V it will charge at 0.6A. If I connect it to a QC2.0 port it will charge at up to 1.5A. if I connect it to a QC3.0 port it will charge at 2A and 9V.

The way the phone identifies the charger is a little bizarre too. There are of course various different implementations, but if the D+ D- differential data lines are diconnected it is assume to be a generic port of less than 0.5A. If they are shorted it is supposed to indicate it is a dedicated charger port and it will pull 1 Amp etc. This doesn't always work in practice though. Apple of course have thier own standard.

2A and 9V is 18W. Realistically, 18W charge power into a 2200mAh LiPo is roughly "2C charge current" which is usually the limit for even high power RC LiPo batteries, I am therefore curious as to how QC4.0 will improve things.

 

[kona786]

Yea although that QC 4.0 only tops at 18w, that isn't any faster than quite a few others already out there, only 3w faster than my 2 year old nexus 5x had.

If that article is accurate.

A quick search and I can't find concrete specs for QC4+

Razer charger is 24W so it would be odd if other QC4+ phones come with 18W chargers.

 

[mrochester]

It’s interesting that Apple seem to be the only company who are sticking to industry standards when it comes to quick charging. Why are more people not complaining about the proprietary methods that these other manufacturers are using?

 

[kona786]

It’s interesting that Apple seem to be the only company who are sticking to industry standards when it comes to quick charging. Why are more people not complaining about the proprietary methods that these other manufacturers are using?

I have the OnePlus I. E. Dash charge. Reason I'm not complaining as I believe to be the best in terms of speed and lack of heat on the phone. And the other reason is that the battery life of my OP5 is so good I never really need use fast charge, as I slow charge every night and I can't remember the last time I've had to top up during the day. The OP5 is a solid 6hr SoT phone in my use.

But yeah I hear you, a universal standard that everyone followed would be ideal.

 

[mrochester]

I have the OnePlus I. E. Dash charge. Reason I'm not complaining as I believe to be the best in terms of speed and lack of heat on the phone. And the other reason is that the battery life of my OP5 is so good I never really need use fast charge, as I slow charge every night and I can't remember the last time I've had to top up during the day. The OP5 is a solid 6hr SoT phone in my use.

But yeah I hear you, a universal standard that everyone followed would be ideal.

It’s a bit like how I never complained about lightning because it’s a much better connector than micro usb even though it is proprietary.

 

[wedrum]

i use a samsung fast charger on my s7 edge its brilliant

 

[Orcvader]

It’s interesting that Apple seem to be the only company who are sticking to industry standards when it comes to quick charging. Why are more people not complaining about the proprietary methods that these other manufacturers are using?

Well Google is too, they've been trying to push USB-PD for a while now.

Qualcomm simply took advantage of the lack of fast charging on phones so they were first with it, which every smartphone maker took advantage of. Then you had other companies following them with their own tech which created this mess. And early versions of USB-PD was more aimed at tablets/laptops so probably why they preferred QC since it was aimed at phones. It's only with the arrival of type C's USB-PD 2.0 which competes nicely with QC, which Google then quickly switched to it starting with the 5X/6P to stay with the standard.

 

[BananaDunka]

S8+ charges with wired fast charging in 1hrs 40 minutes from empty. Seems fairly standard, the S7 edge does the same run in the same time. Samsung's adaptive fast charge is hard coded to control the voltage/current this way really. This is with any QC2.0 compatible wall adapter, inc the Samsung official one.

It's worth noting that Snapdragon SoC Galaxy phones also support USB-PD, something this article does not mention.

Samsung's next flagship might support QC3.0, but I'm hoping they up the game and support 4+ instead with the S10. It's about time we moved away from QC2.0 on Galaxy phones...

Wireless fast charging isn't mentioned in the article either. It only adds an extra hour to the 0 to 100 run on the S8+

 

[BUDFORCE]

USB-PD is pretty quick.

This Huawei P20 lite runs on QC 3.0 and supports up to 18w (9v/2a), it has a 3000 mah battery and it takes about an hour an 40 minutes to charge from empty to full.

My old Nexus 5x on USB-PD is up to 15w (5v/3a), had a 2700 mah battery, however that would charge from empty to full in about 55 minutes.

Now I know the Nexus has a smaller battery but you only need to eyeball the maths and it's clear, despite apparently faster potential charging speeds on QC, the USB-PD device charges faster.

Looking around it seems those results are pretty typical for phones on the same charging standards.

So looks like USB-PD devices do charge faster than QC, a lot faster actually.

However, the QC charging standard comes on nearly all phones with Qualcomm chips, which account for a lot, plus the software for the standard is from what I've read, a completely free license, so all phones can adopt the standard from Qualcomm free of charge even if they don't use Qualcomm hardware or also adopt their own standard as well.

In turn, 3rd party QC chargers are cheaper, plus QC charging standards also work down micro USB connections due to the way it increases the voltage (more volts = less current = less heat - works on a thinner cable) where as USB-PD is restricted to USB-C as it pushes more amps down.

Be interesting to see what happens going forward.

 

[PaulCa]

One consideration for higher and higher rapid charging rates is if you take a look at LiPo datasheets they list figures for how many cycles the battery will go through before it's capacity drops to 80% of it's specification. These are listed based on charge and discharge rates. The higher the charge and/or discharge rate the less cycles you get before you lose 20% of capacity.

The numbers are not all that high for high charge rates like 2C (2xCapacity, ie charging a 2200mAh cell at 4.4A) They are down into the few hundreds of cycles. (Note that C charge rate can be gained from dividing 1 hour by your charge time, so 15 min charge = 4C charge rate (dangerous))

A mobile phone is a highly hostile place for a LiPo due to high heat from the CPU, screen and your pocket in addition to
being kept fully charged for long periods, high charge rates, when not necessary is just going to wear your battery out all that much faster.

Shorten battery life: High charge rates, high heat, high charge state (and not common in phones, high loads, over charging, over discharging).
Lengthen battery life: Cool. Mid 40-80% charge state. <1C charge rate. Light loads.

If your phone gets warm when charging it's a full on assault. High temps, high charge state, rapid charge rate.

Of course. How long to we keep phones these days? 2 years? 3 years? Even under abusive duties, losing 20% a year the phone is usable for a couple of years and probably tolerable for another year by which time it will be slow and have stopped getting updates. That old consumer disposable cycle of "progress".

 

[BUDFORCE]

Yea thing with battery wear though, that nexus 5x I had that charges twice as fast as this, was 22 months old with regular use, acubattery reported the battery at something like 85% capacity. Which is minimal plus it probably comes out of the factory at less than 100 anyway.

Also, whilst not a removable battery as such, it was really easy to do, and a replacement battery was dirt cheap.

One thing I never did though was leaving it on charge over night.

But no doubt fast charging increase wear and particularly over 80% but if that nexus was anything to go by they can take it and the convenience of being able to get a good charge in a short space of time is worth it, but as you at, there is a limit.