I am testing if it takes _longer_ to "fast charge" a phone if you _frequently_ let the battery run down to zero - and it seems to be.
Case in point, I've been letting the phone run to shutoff overnight (by running NewPipe YouTube videos and disabling the screen shutoff).
In the morning, invariably, when I boot the phone back, it's at 4%.
Then I have a sentence that says "your phone is at 100%" so I don't have to watch the charging go on, and then I snapshot the status periodically.
Lookit this!
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Fastcharge in about 2 hrs
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Fastcharge in 2-1/4 hours
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Fastcharge in 2-3/4 hours
Just what one might expect (although I agree the dataset is minimal). I'll keep testing this as I'm curious what happens in the real world.
Luckily all modern phones nowadays have huge batteries so it matters less how long it takes since it always takes less than 3 hours from empty using the charger that came free in the box (and which I didn't have to buy).
Anyway, here's the full set (notice I went from Android 11 to Android 12).
It appears to be BAAACK. Please do not feed the troll.
In the off-chance that this is NOT Jimmy Neutron in its latest incarnation:
a) It is really, really stupid to run any battery 'down to zero'. They are chemical engines that are damaged by this behavior. Without exception. b) Should you have the discretionary income and time to pursue this activity anyway, you certainly do not need approval from this or any other venue. c) Most of us here (OK, at least a few of us here) well understand the nature of batteries as chemical engines and do not need to re-invent the wheel. d) Those that do not deserve exactly what follows.
Somewhat related, I saw this past Saturday an article about a study testing charging batteries to full (of electric cars), or only a percent.
The article is in Spanish, but you can use google translate to read it. It points to a study in German, but I do not see its link.
Seems that the best is to limit the battery cycle to 20%/80%. Interestingly, my new moto g52 phone can limit the charge to 80% and has functionality to disconnect charger when its' been continuously connected for 3 days. I don't know if this will work with any charger or has to be the manufacturer one. I think the former.
I have no idea. In my entire experience using mobiles I've never gotten to zero. I take my phone off of the wireless charger on my night table every morning, use the phone all day, and every evening I put it back. Sometimes it might be down to 35-45%. Last night, for the first time that I recall the phone warned me that it was low and was going into battery saving mode. That really shocked me but, looking back, I had wasted _many_ bored hours at the Subaru dealership and the phone was active much more than usual. As for damaging the battery, I don't worry since the "adaptive charging" feature is gentle, making sure that the battery is up to full by alarm time in the morning but never forcing the matter. There are important things in life to worry about but charge times is not one of them, for me at least.
There are two ways that EV makers are able to guarantee their batteries for 100K miles. The first is to limit how high it charges and how low it discharges. The second is to define what constitutes "excessive capacity loss."
Me too. I have always done it that way whether with wireless or regular chargers. 100% charge every morning. And so far the battery has always outlasted the phone before being replaced. And I've never needed it (yet) but that extra 20% charge just might come in handy someday...
Same here. I never think about charging, other than throwing it on the charger before going to sleep. Our devices are here to serve us, and not the other way around. Personally, I have far more productive things to do than babysit my devices.
Why? Kinda reminds me the Chernobyl, where the fools were trying see if they could squeeze some power out of the reactor that was almost, but not quite shut down. It didn't go well for the Russians and is likely to go badly with your battery.
Couldn't you just recharge the battery starting at 20% of capacity and live with that? If you must run your phone overnight playing videos that nobody watches, then buy an external battery bank and do your best to kill it.
Do you also add gasoline to your car just before you totally run out of gasoline?
Also, I have a little experiment going with two friends. We all have the same Moto G Power (2020) phones that were purchased with a month of each other. I also have an identical spare (loaner) phone, that I don't use much. Usage patterns and apps are quite different between us. So are the battery recharge patterns. Two of us use the stock 10 watt charger, while one uses a 30 watt charger. I also have a 30 watt charger, but have only used it maybe 3 times, when I really needed a fast charge. After about a year of data logging (using AccuBattery Pro) the batteries on the 10 watt chargers are currently at 97% and
98% (from a 105% start when new) of the rated 5000ma-hr capacity. The phone on the 30 watt charger is currently showing 92%. The implication is that fast charging is slowly killing the battery. I tend to recharge mine when it is 50% charged. The owner of the 30 watt charger seems to recharge at 20%, which might be another factor in killing his battery. Partial screen grab:
Interesting to see it born out in practice, but it is a known fact. Fast charging heats up the battery and heat damages the battery, therefore fast charging will reduce the battery life.
Actually there is no evidence that "fast charging," at the rates we're currently seeing on most phones, damages batteries.
The phone firmware manages the charge rate. If you look at the Galaxy S22, which Samsung touts as having a charge rate of up to 45 watts, there is barely any difference in charge time between using a 45 watt charger versus a 25 watt charger because the phone manages the charge rate and the high rate only occurs when the battery is nearly empty. The phone reduces the charge rate as the battery charges.
"According to industry experts, a battery when charged with a fast charger is most stressed after the 80 percent charge level. This is the time when high voltage current is not absorbed by the battery as efficiently as it does when charging from zero to 50 percent. Lithium-ion batteries are like a sponge – they absorb the charge efficiently during the initial phase and begin to drop-off after 70-80 percent charge level.
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. If you plug in a USB current/voltage/power meter during charging, you'll see that the phone reduces the charging rate as the battery charges to prevent stressing the battery.
The iPhone 13 Pro Max has a 16.75WH battery. Battery manufacturers recommend a charge rate of 0.8C or less which would mean a 13.4W charge rate. But the 0.8C recommendation is misleading because it assumes a constant charge rate all the way up to 100%. In reality, there is no damage from a higher charge rate when the charger rate is tapered down as the battery charges, which is exactly how phones are now designed. When you're talking about really fast charging, like the 200 watt charging that Xiaomi is coming out with, then that may be another story.
Nope, or at least not what I've seen with my testing (and screwing around). A few decades ago, I decided that NiCd cells would only become warm if over charged past 100%. Well, I was off a little but my thermocouple tests showed that up to about 75% of full charge, I could literally charge the NiCd cell at whatever sky high rate I found amusing. The problem was that if I missed and went over about 85% of full charge at the ridiculous rates I was using, the cell would generate enough gas and heat to blow the end out and generally make a mess.
Roll forward to a few years ago, and I'm doing the same charge tests with LiIon cells. It was pretty much the same story. I could charge at almost any rate I wanted as long as I didn't go over about 75 or
80% of full charge. The battery remained cool and did not overhead. Past about 75%, the cell started to get warm. You can easily reproduce the effect with any LiIon fast charger and a phone app that displays battery temperature. I think I was using DevInfo Pro:
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Try: Temperature tab -> chrg_therm and Temperature tab -> battery Sorry, not graphs but other programs will plot most of the internal sensors. Unfortunately, you won't see the battery temp rise very much because the phone reduces the fast charge rate at 80% to some lower number.
My guess(tm) is that it's not the temperature that kills the batteries, but rather the charge rate and number of charge cycles that does the damage.
I realize that it's anecdotal evidence, but two identical Moto G Power (2020) phones, charged with 10 watt and 30 watt chargers, seem to show that the measured battery capacity (ma-hr) is dropping for the 30 watt charger. I'll admit that it's not much in the way of evidence or even a controlled experiment, but it should provide a hint that there might be a problem.
About 6 months after I bought my first Moto G Power (2020), I bought another identical phone on eBay as a spare and loaner. It arrived with a battery life showing 97% of rated capacity. At the time, my original phone was showing 105%. I asked the sell what he was doing to cause the decrease. I eventually found that he was using replacement charger that indicated "Turbo Power connected" on the home screen, which methinks is Motorola speak for 30 watt charging. My 10 watt charger displays "Charging Rapidly". Not the best evidence, but does suggest a possible problem. Also, it's difficult for me to perform battery life tests because the phone will be obsolete by the time my testing is complete.
It's also an established fact that running a battery down to zero repeatedly will increase heat and prematurely age the battery as well. Laughably, Arlen (Andy) is willingly harming his battery for no real benefit. You can't fix stupid. ¯\_(ツ)_/¯
That's like asking a chemistry teacher why there's a chemistry lab. Or asking a physics professor why she bothers to run the lab. Or asking why a microbiology class bothers to grow bacterial cultures.
Bear in mind that the answer to the question of what kind of charging damages a smartphone battery has about a billi... no... a few billion questions on the Internet... with answers spanning the globe.
So it's not just me who is curious what happens in the real world.
I've always been curious about the best way to do almost any thing. And destructive testing is a fantastic way to figure out what really happens in the real world under real world conditions, even as you can't hope to run a "consumers report" style full-fledged scientific investigation with basic home equipment.
Still... I try to learn... and destructive testing is part of learning. When I was a kid, my dad kept a box of old "stuff" for me to take apart.
The first time I took apart a 6V battery, it stunk and was all crumbly. But then I _learned_ how they make 9V batteries by taking it apart. And, I was shocked when I took apart a Radio Shack D-sized NiCad battery!
In graduate school, I was tasked with figuring out why defibrillators failed and then when I took apart the batteries, I was shocked (in the opposite direction!) when I took apart their GE C-cell soldered battery assembly).
What a freaking difference between the Radio Shack "D", um, I mean "secret C" cell Ni-Cad and the GE industrial strength C cells by weight alone!
I shorted them, of course, where the Radio Shack c cell barely burned the wire but where the huuuuuuuuuuuuuuuge current surge of the low-impedence current source of the GE battery literally burned out a Romex ground wire!
When I took apart old TVs, I would marvel at the intricacy of the vacuum tubes and when I imploded the monitor, I was surprised by the force. I'd even marvel as the lovely yellow selenium (I think it was selenium) plates which were used as diodes (although I was sure not to overheat them!).
When I took apart a 1950's baseball catchers mitt and my mother's 1940's era high heels, I marveled at the fantastic construction, just as I did when I rewound my own alternator coils (it's hard to keep the wires taught enough not to vibrate and to coat them with a non-conductive heat-resistant coating with just a kitchen oven and bench vise).
I replaced my battery's sulfuric acid and I autopsy every part that ever failed on my cars and bikes just so that I learn how & why they failed.
When I moved from NY I had to empty my welding tanks, so I filled up balloons with oxygen and acetylene, and I _learned_ how _loud_ that could be.
In chemistry class, I mixed iodine crystals with nitric acid, and after drying with alcohol and acetone, a fly landing on it would touch it off (emanating a lovely purple cloud).
In Physics lab, I'd stick circa 30VDC large electrolytic caps in the lab bench switched branch of electrical sockets - which I'm sure you know what they looked like even before the autopsy.
To learn about impedance, I literally hooked up a 120VAC circuit using _only_ capacitors, resistors and coils, where, since you know the math, it's hard to find handy the right size for those things.
I even ran an autopsy on my cat (internal damage as far as I could tell).
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