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Charging a lithium battery to 80% only?

electronics.stackexchange.com

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Re: Charging a lithium battery to 80% only?

#271

Post by nottorp »

Zak wrote: post #261
venj wrote: post #169

Earlier quoted context omitted.

I think a lot of laptops do this because their cooling system is too weak for the CPU. The Lenovo Thinkpad t480s comes to my mind: with factory settings, the CPU was unable to reach its advertised boost frequency nor maintain its max non-boost frequency for more than a few minutes. After 5 to 10 minutes, the machine was usually running at 300/400mhz under its advertised clock speed. Undervolting helped a lot but coul…

Thinkpads, for a long time have had a fan speed that's possible, but never reached by the firmware's automatic mode. On Linux, this sets the fan to its true maximum: # echo disengaged > /proc/acpi/ibm/fan I use the thinkfan utility to run the fan more aggressively, including 'disengaged' over 70C.

How's your hearing? If any left.

Re: Charging a lithium battery to 80% only?

#272

Post by hunter2_ »

bayindirh wrote: post #240
internet2000 wrote: post #235

Earlier quoted context omitted.

That’s the weird part, they actually can. It’s supposedly one of the machine learning features, where it learns your schedule and makes daily accurate guesses of by when you’ll unplug and plug it back in.

> ... they actually can. Yes, it does. Even my 7 years old iPhone X does it. I use some features at very specific times, and it suggests me "do you want to do X?" around the time I do that. So the models work well. Also, the phone generally enables optimized charging if I put it to charge too early. Scheduling to finish a couple of hours before I wake.

> I use some features at very specific times, and it suggests me "do you want to do X?" around the time I do that.

You're conceding that you have a predictable schedule. Folks on the other side of this (who believe it can't work nearly as well as manual control) don't have a predictable schedule. Think of it like {hybrid workers who use a desk all day the same 3 days a week, and are nomads the other 2 days a week, and the ML system can figure this out} vs {on-site workers who use a desk all day 5 days a week, but are nomads a few random days a year, which always catches the ML system off guard}.

Both are valid. A setting that caps it at 80% unless you hit a button for "I'm about to spend a lot more time unplugged than usual, so prepare the battery for that" is the only way to handle unpredictable circumstances. Just like preparing an EV for a road trip.

Re: Charging a lithium battery to 80% only?

#273

Post by Izkata »

p1necone wrote: post #21
belltaco wrote: post #14

I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge. But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Appl…

I'm pretty sure most (all?) manufacturers already do (the first part of) this. 100% can't be the point at which the battery literally stops taking new charge - if you did that they'd catch fire all the time. It's just that the manufacturers idea of what "100%" should be generally skews more towards the immediate battery life end of the tradeoff, whereas some users prefer to have "100%" closer to the maximizing long t…

> I'm pretty sure most (all?) manufacturers already do (the first part of) this. 100% can't be the point at which the battery literally stops taking new charge - if you did that they'd catch fire all the time.

It's a really tiny amount, like 101% or 102% is the maximum. It becomes obvious on phones if you have an app that shows battery percentage over time - above 90% on a slower charger (like using USB instead of AC) it tapers off in a curve, even on a brand-new battery.

Re: Charging a lithium battery to 80% only?

#274

Post by bayindirh »

thfuran wrote: post #249
another2another wrote: post #237

Earlier quoted context omitted.

My colleague just had to replace his HP Elitebook Notebook because the battery had bulged so much it had cracked open the case. For this to be happening in 2023 means that some manufacturers at least, seem to be not managing this potential problem at all.

N=1 doesn't really tell you much of anything about anything.

Well, my wife's work supplied EliteBook's battery has been replaced today due to excessive swallowing, and it's definitely younger than my 2014 MacBook Pro.

Re: Charging a lithium battery to 80% only?

#275

Post by 0xbadcafebee »

Another important rule: Never leave a lithium-ion battery at 100% charge (or https://www.washingtonpost.com/technology/2022/04/18/lithium... https://bgr.com/tech/samsung-galaxy-batteries-might-have-a-s... https://www.reddit.com/r/spicypillows/comments/gebotv/faq_wh...

Re: Charging a lithium battery to 80% only?

#276

Post by ajmurmann »

watwut wrote: post #141
belltaco wrote: post #14

I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge. But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Appl…

Another reason is that batteries are ... small. Too small. If it charged to 80% from the get go, then your phone is already effectively living on reduced battery, it is already kinda broken because battery runs out too quickly.

This really depends on the person and use case. Pretty much the only time I get even close to depleting my phone or laptop battery is during air travel which happens like 2-3 times a year. Otherwise I charge the devices throughout the day at my desk where the laptop is plugged in 98% of the time anyways.

Re: Charging a lithium battery to 80% only?

#277

Post by koromak »

teekert wrote: post #252

I always try to keep between 20-80% with my iPhone and consequently always feel bad about my AirPods. The case is always as empty as possible, the pods as full as possible. They spend almost their entire life at 100% as a result of the charging case. Even though I always use them at a max of 1 hour or so at a time. In other words: I first need to drain the case to the very bad 0% to get the pods to go down, otherwise…

Well if it matters, I'm astounded at my airpod Pro's battery life. Going on four years of daily use, and I still get 3.5 hours straight hours out of them every night

Re: Charging a lithium battery to 80% only?

#278

Post by nottorp »

dandy23 wrote: post #107
hilux wrote: post #79

Earlier quoted context omitted.

It's well-established that iPhones have longer average lives than Android phones.

Really? If that is true, I wonder how much is due to the fact that the phones are more expensive so people take care of them more or delay their next purchase. It's not because the actual quality would be better. If you pull statistics you also have to filter out the sub 150 dollar Andoid phones which may well have shorter average usage life.

> If that is true, I wonder how much is due to the fact that the phones are more expensive so people take care of them more or delay their next purchase.

Delay because it's more expensive? How about delay because it's good enough? My iPhone XS is just fine thank you. There's no point in upgrading it yet.

Re: Charging a lithium battery to 80% only?

#279

Post by djmips »

talldatethrow wrote: post #92
djmips wrote: post #75

Earlier quoted context omitted.

You did all this in 15 minutes? https://www.youtube.com/watch?v=m1gVWGAw8do Let me guess, the back cover wasn't stuck on very well from the repeated battery replacements.

Yes, 15 minutes or less. There's like 3 screws to undo on the battery clamp and 4-5 for the camera or whatever. That's it. I suppose yes it was a not stuck together as well as a new phone.. I wouldn't know since a certified Google place had fixed it prior. So if it was stuck together like new, it would have taken me a few extra minutes with a heat gun. Still much much faster than having a pro do it for me.

Well that's comforting because I have my Pixel phone and a new third-party battery sitting in a box on my desk and I feel just a little intimidiated to tackle it. I will try it now.

Re: Charging a lithium battery to 80% only?

#280

Post by shortcake27 »

Rapzid wrote: post #266

I'm a simple man. My phone needs a charge I plug it in. When it's charged and/or I need it I unplug it. I largely trust companies to get these basics right and haven't had an issue.

> and haven't had an issue.

Every lithium battery in every device you’ve used has degraded. It’s not a manufacturing issue, it’s a chemistry issue.

If you haven’t had an issue, then you aren’t paying attention, or you don’t keep your devices for long enough for the degradation to be a problem. This doesn’t mean there’s no issue, this just means the issue doesn’t affect you personally.

A small change in charging habits could prolong the life of billions of devices, a huge win for the environment. You shouldn’t be so quick to dismiss the idea just because you personally aren’t affected.

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