TL;DW: Fast charging over 2 years only degraded the battery an extra 0.5%, even on extremely fast charging Android phones using 120W.
And with that, hopefully we can put this argument to rest.
It’s as if engineers knew what they’re doing.
If engineers were the ones in control that would mean something.
As I see it, phone manufacturers have zero reasons to keep the battery degradation low, but many reasons to push advertised capacity and charging speed. If you were cynical, you could also assume that they’re trying to make sure the battery doesn’t last too long because they want to keep selling new phones.
I think we all know that if an engineer went to upper management and said “I can charge these batteries faster, but it degrades the battery life by 20% over a year.” they would have said “Do it! We won’t mention that last part.”
Yep. I’m gonna miss real engineering with the coming Ai-driven Idiocracy.
Engineers have the best of intentions. The Bean counters have very different intentions and they’re the ones that corporate listens to.
“And with that, hopefully we can put this argument to rest.”
That’s not how the internet works, but nice try though ;-)
I disagree!
However the Battery Saver mode on Androids that only charges the battery up to 80% DOES extend battery life. Substantial evidence shows that a high State of Charge accelerates degradation through: solid electrolyte interphase growth, loss of lithium inventory, and loss of active materials. (See: mdpi.com)
Here’s a fun fact: phone manufacturers know this. So what they call “100%” is not actually 100%. Your phone will not charge your battery to full. Battery charging is already designed around this.
That depends on the manufacturer, some do, some don’t. My phone has a setting to control the max charge, so I set it to 80% when I got it.
Yes, but that 100% is not really that. It has been programmed to display that percentage, when i reality its 80%.
No, I’m saying that not all manufacturers have that limit, and it’s a relatively new setting (last few years). If you have an older phone or something not from the top few manufacturers, it might not have that feature.
This is like spinal tap. Yeah but my phone charges to 110%. I don’t think you understood what they’re trying to say. Changing what 100% means isn’t a setting or “relatively new”
I’m saying when your phone charges to 100%, some manufacturers take that to mean 80% of capacity, whereas others actually charge the battery to 100% of capacity.
Exactly, which is neither a user setting or relatively new. Battery manufacturers have always had to decide what voltage is what state of charge (percent).
The user setting where you limit it to 80% is on top of what the previous commenter was describing
No, they’re saying that some hardware manufacturers report 80% as 100% (as you noted) while others do not. Just like some manufacturers report 5% as 5% while others report 10% as 5% with the realization that most people misjudge when they’ll be able to charge.
Source?
I always find the same study referenced, which was good science but also almost 30 years old. I wonder if this is still true for modern batteries?
Correct me if I’m wrong, but as far as I know there haven’t been significant changes in Li-Ion and LiPo batteries aside from extra density - which would only increase the effect. But it seems like solid-state batteries are starting to hit the real world now
I bet thats wrong, but I know ….
There’ve been usage changes
- iPhone has “Optimized Charging” where it predicts usage and tries to keep about 80% charge until it expects you to use it
- iPhone has “Adaptive Performance “. Maybe not charging but tries to gradually ramp to “low power mode” to be gentler on the battery
- all phones likely have refined charging curves to match battery technology
FYI: During this test it saved about 5% of SoH.
Betteridge’s law of headlines: “Any headline that ends in a question mark can be answered by the word no.”
„Is drinking Paint thinner really as bad as everybody says?“
Well. It could be worse than what everybody says
is the poupe deck really what i think it is
Corollary:
How not following trends and drinking paint thinner boosted my B2B sales
No.
Are we talking about water-based paint?
TL;DW: No
I hadn’t watched the video yet, but my phone’s going the opposite way. It run slow charge overnight when it feels like it’s going to be enough for it to be fully charged the next morning.
We really should let electronics and tight software take care of these little things.
Non-magnetically-aligned wireless chargers are far worse than fast charging.
Far worse at what? Wasting energy? That isn’t what the video is testing.
At killing batteries faster - the wasted energy creates heat, which degrades the battery.
That makes sense but has it actually been tested?
But keep in mind the phone will throttle charging speeds when it gets warm, so the battery doesn’t end up getting much warmer, it just takes forever to get a full charge (especially when using a thick case that puts further space between the charging coils and also acts as thermal insulation, thus reduces the phones ability to cool down)
It is still keeping the battery warmer which degrades it faster regardless if its being charged or not.
Wireless charging is a gimmick like 3D TV was. There’s only one use case, and it’s car use. But it doesn’t need to be fast. In every other case it’s worse than cable in every aspect
A phone with wireless charging is a bit niche, but if only all my little devices had wireless charging; earbuds, vape, tablet, controller, remote, etc. I’d set a charging mat in the middle of the coffee table and have all my devices just be charged and ready to go. Now it’s just a mess of wires, with the only thing I keep glued to my hand featuring wireless charging!?
I’m hoping for ranged wireless charging. Everything is always charged when Im inside.
Just live in a microwave. Problem solved!
Not doable without some very expensive addons to your house - like IR charging from ceiling
Everything is always charged when Im inside.
That’s living in microwave, I’d say its not going to ever happen
https://news.mit.edu/2019/converting-wi-fi-signals-electricity-0128
I’m fine with infrastructure overhaul. We build new houses every day.
We just need to be clever enough to do it without cooking ourselves
Wifi is limited to ~100 miliwats of power, and what reaches you and your phone is in range of microwats or even less. You can’t charge your phone with it.
yup, the chinese brand have it right. Fast charging is amazing, just put the phone on charge for like 10-20 minutes and you can forget about your battery for another day. It’s great.
I have a one plus phone.
The super vook charging works very well. It feels like less than 10 minutes to go from 10 to 80 percent.
The Chinese have it right with the food too. Love me egg foo yung
[citation needed]
Ok, before i watch the video, no damage is not what great scott found from his testings… ( https://youtu.be/iMn2yVoEqPs ).
so i have no idea what to believe anymore, but my (based) experience is that it does damage it. Ill have to watch later.
Yea, but that wasn’t a great rest. I love Great Scott, but a lot of comments fairly call out his conclusion.
Most (all?)phones don’t charge at full speed to 100% charge, they fast charge when the battery is almoast empty, and charge slower the more full it gets.
Right, so basically he removed the software aspect in his tests which removes systems to protect the battery. I assume without them, it is damaging, like what great scott found.
Ye, he should have continued his experiments then!
I’ve got some devices I’ve been fast charging for 8 years; it seems to be more of a problem as the device ages; but that’s offset by having it ready to use again quickly.
This is the type of scientific method that can put all this nonsense to rest. I really appreciate their work proving that the difference between fast/slow/30-80% is insignificant to the majority of people.
Thanks!

Just what I wanted to know. Thanks!!
That’s a great TL:DW;
Now I want an iPhone that can charge in 20 minutes. :)
Wish granted, the battery is now small enough to slow charge to full in 20 minutes.
Tap for spoiler
The iPhone air is great, isn’t it?
As humorous as this sounds, this is not at all how battery chemistries works.
Some chemistries just charge faster than others.
for the common types of Lion or Lipo batteries, they max out pushing 2C which is around 30 minutes.
For something like LTO, where you lose capacity/density, you can get that up to like 4C (very rough numbers here as this all depends on the temperature of the battery while charging, age and other factors).
So like… this could have been accurate if this was referring to switching to LTO, but afaik, no one makes LTO batteries in this form-factor (not that it can’t be done though).
So put in a big-ass battery and artificially block it at 20% for “full”? 😁
I’ve been a “Pro” user for as long as they’d had that distinction vs. lower end and the “it’s a small tablet” size.
He he Xiaomi 120 watt charge. 19 minutes from zero to full. Well I only have tried from like 12% to 80+ because that was more than enough and I wont let it go to zero-zero. I don’t use it regularly, not because I fear for my battery but it does get the phone warm and warm/cool cycles are bad for electronics.
The day the battery degrades I’ll just have it swapped for a new one, I think we’re far enough into the battery revolution to no longer really care about all this any more.
That’s pretty awesome
I love when YT amateurs act as if they are able to produce proper studies that are relevant in any fucking way
If you have a problem with it, tell us why.
I personally prefer a proper peer reviewed study over amateur YT slop
I have no skin in the game but I have worked professionally as both an academic scientist and a data scientist in the private sector and I can tell you that peer review is great but a lot of legitimate research is done outside the bounds of academic journals. It is entirely possible for amateurs to do real science.
If the effect size is large enough, you dont actually need to be that rigorous about it. No one needed to do a study on whether there was a direct correlation between adverse medical outcomes and gunshot wounds to the head.
I personally don’t trust the little (probably superficial) insights I have into the topic enough to be able to gauge this; neither do I have the energy to put into discerning slop creators doing it for clickbait with some backyard engineering or genuinely correct amateurs.
I like to outsource that to proper channels, I understand that it’s probably not 100% fair every single time, but as I said, I have neither time nor energy to judge it properly myself
Person: offers you an apple
You: “Personally, I prefer organic, homemade apple pie! Not APPLE SLOP!”
Sorry, but it’s more like a crab apple.
It looks like an apple, it’s presented like an apple, it’s advertised like an apple because that is what makes the YouTuber money. But scientific methods and standards exist for a reason. It’s very easy to produce bad data and especially easy to extract bad conclusions from data if you have an incentive to do so (such as a fan base who might engage with the video less if the conclusions were against their expectations)
There’s a chance that this guy’s conclusions reflect what a proper study might have found, but it’s just too hard to tell if it’s a crab apple or not it’s essentially probably a little better than chance.
Exactly, when it comes to highly complex chemical and electrical engineering and physics (as is the case with Smartphones and their lithium-ion batteries), I will take it as an inditcator if it comes from well-established testers with professional equipment like GN (Gamers Nexus) or other established technical journals when talking outside of the video world, but will not accept it as a general and genuine technical (!) insight until it has gone through the due process of scientific publishing and peer review…
Even then I prefer meta-studies, since they reduce biases and general inaccuracies.
I think this accurate or close to it for phones but my laptop battery a Dell has degraded very quickly through 50 plus or more cycles of battery like 15 percent. It went from 59wh down to 50wh and it ebbs and flows. Runs Linux mint and installed power top and some other low power mods to help dumb things down to conserve. I feel like arm processors vs x86 are wildly different.

















