[denimnerd42]

what's frustrating is that while batteries are consumable products they could last much longer if they stay between 80 and 20% capacity without overheating. (this is similar to what tesla does) I wish there was a "battery care" settings on all electronics that would respect limits like this so that I could get thousands of cycles out of my devices instead of only <1000.

Apple has added a feature which tries to do this intelligently to some extent but it's not the best at guessing what my needs are.

The majority of the time I do not need max or even half of max battery life from my devices. airpods I only use for an hour or two at a time for example and my phone is usually close to a charger.

[aetherspawn]

Ex EV battery engineer here. You’re right that the cycle life of a lithium battery typically doubles per 0.05V (‘tik’) undercharged from 4.15V (and on the other end of the scale as well, less so).

This typically corresponds to around 7-10% capacity per ‘tik’, so to effectively triple your battery cycle count would reduce the runtime by approximately 30%.

Interesting effect here.. the amount of power in each cycle is less because you’re undercharging the battery. And for each consecutive ‘tik’, 0.05V is approximately more power because the discharge curve becomes flatter (voltage != state of charge). It doesn’t scale like you’d think. Seriously diminishing returns!

[justnotworthit]

Could you tell me if the "under X%" claim is true about battery? I saw an old study that didn't seem to be affected by how low the charge got, just heat (fast charge) and time spent charging over 80%.

[tbrock]

Apple is the only laptop manufacturer that even gets close to 1000 cycles of great battery life.

[fomine3]

Lenovo and other manufacturers provides configuration app to limit State of Charge for battery over a decade ago. Apple just implemented similar feature (but automatic) in 2020. Without that, battery is unnecessary degrading while plugged into AC with 100% SOC.

[w0m]

As seemingly half my coworkers needed batteries replaced on 2018 macbooks last year roughly as applecare ran out due to not being able to charge and work at the same time.

[mmastrac]

Honestly, has anyone gotten 1000 out of a MacBook? Mine always goes to "service battery" around 300-400.

[deathtrader666]

I have a "Service Battery" notification since 3 years, still gives me 4 hours.

[w0m]

Can charge while working the machine still? Teams/Docker/etc chugging and charge % steadily dropped irregardless of port/charger used.

[vikbytes]

I got that warning on my Macbook Pro from 2014 after ~820 cycles.

So, somewhat close at least?

[Hamuko]

I think I got a pretty high number out of my first MacBook Pro before the battery swelled up like a bad bruise. But my current work laptop is now at 87% capacity with 82 cycles, so I don't have a lot of confidence in the battery lasting to 1000.

[ad404b8a372f2b9]

That's not been my experience, all the Dells I've owned have had great long lasting batteries.

[tinus_hn]

Dell batteries last about 2 to 3 years of extensive use, we replace them all the time. They are easily replaceable though.

[DeliriumTrigger]

It's nice having a battery when their soldered ssds crap out after 5 years.

[polishdude20]

That might be what's already happening behind the scenes though. They tell you you're at 10% but that's actually 30% for example

[stefan_]

For cars, maybe, but my org has had a long line of HP laptops with swollen battery packs within a year of use. No doubt there are companies out there that would rather have the extra hour of runtime on some journalists review fact sheet than a battery that doesn't put their customers at risk.

[eitland]

I hope all those gets replaced under warranty?

I hounded Dell for months and got them to replace I guess 2 or 3 dozens of Optiplex DL270 motherboards and it felt good: forcing them to take the cost for their shoddy work.

[stefan_]

They do but in the meantime you got a laptop that only works off AC.

[eitland]

Sad to hear.

The times I had an issue with an HP business laptop I called them and either a technician came to my office and replaced the part (a screen in that case) or they sent a spare after confirming I was capable to change it myself.

[HPsquared]

There's another side as well though - a failing battery will stop working unpredictably, which is also very bad for business/productivity.

[alisonkisk]

That's heat damage not discharge.

[SV_BubbleTime]

Good point, and it is/does for many products. EVs beyond Tesla all do this for instance.

I do wish there was a little more of treating your users like adults though. If I have enough battery to make an urgent call, but it puts me under the 20% recommended, I want to make that call at the cost of long term battery life.

My products treat users like adults, I wish it was a more common consideration.

[ddingus]

My Note 8 phone has a charge battery notification at 15 percent.

I just replaced that phone, and yes with another one because I happen to like that model a lot, and my old one did 1500+ cycles with respectable battery capacity remaining. I replaced it due to a cracked screen, not battery trouble.

My general experience has been to avoid fully charging the battery and leaving the device on the charger, plus avoiding high demand use under 15 to 20 percent adds very considerably to longer term battery health.

This has played out across a number of devices, lenovo laptop, various phones.

After, say a few hundred cycles, it's very important to avoid taking the battery below 5 percent or even to zero. When that happens, the battery capacity is reduced every time, and it's by a significant amount.

[elliekelly]

It does feel like the final 10% of battery lasts way longer than the drain from 20% to 10%.

[cptskippy]

As batteries discharge their voltage drops. This is known as a discharge curve. The curve is based on a constant current, different current draws have different curves.

http://learningrc.com/wp-content/uploads/2017/02/Lipo-Discha...

Battery capacity is guessed by the Voltage output at the current draw when measured.

Laptops usually throttle components, reducing current draw, when they fall below certain percentages. This prolongs the battery so that last 10% really does last longer.

This article goes into some nitty gritty details if you're curious.

http://learningrc.com/lipo-battery/

Determining actually battery capacity and runtime are educated guesses because all the factors impacting them are constantly changing.

[ddlutz]

estimating battery life is hard, it might be due to that.

[w0m]

I think they start cutting performance significantly for that final ~10%; screen dims; cpu undervolts, etc.

[denimnerd42]

10% vs 30% corresponds to whatever arbitrary voltage they select but I doubt they are selecting for battery durability over all else since marketing max run time is so important.

[SV_BubbleTime]

Automotive engineer that doesn’t work on EVs here… there is a lot that goes into the battery. Heating and cooling elements for instance. You’re right, max runtime is the number one factor, but this can be gamed just like MPG ratings.

I’m not sure many reviews are checking 0-60 times at 20% battery for example.

My EV has a hilarious “miles remaining” number that INSTANTLY changes when the HVAC is on, doesn’t matter if it’s only slightly on or not, I instantly “lose” 8 or 9%. It’s pretty loose. As to what I actually get? Doesn’t really matter, never even compared to rating, mfgs know we use these cars for city travel.

The small percentage of EVs you see on long haul highway, owners already know to carefully plan their trips.

[cduzz]

Depends on the locations and cars in question; on the east coast there are lots of DC Fast charging stations between anywhere and anywhere else.

This is double true for Tesla where there are superchargers nearly everywhere. With access superchargers, road trips are roughly as complex as driving a diesel with a 5-8 gallon tank.

Also the tesla UI is very good at managing the trip so it is trivial to offload the "how do I get there including charging" task to the UI.

[jimpudar]

That was IIRC how the Chevy Volt worked. Empty was actually around 20% and full was around 80%.

[GekkePrutser]

Well the good thing about these kinds of buds is that your rarely discharge them heavily. Because you always put them back in the case. Mine never go below 50% (don't have airpods but cheapie €20 xiaomis that work surprisingly great).

But it would be nice to have an option to avoid 100% yes.

[wonnage]

There are a lot of complaints about the buds not charging in the case, most likely due to not making full contact with the charging pins. The buds have no auto-sleep feature for some reason, so they'll stay connected until the battery runs out.

Not only is this annoying, it also adds tons of unnecessary full discharge cycles.

The new wireless charging cases are also bad - they seem to stay warm even when no longer charging, which probably degrades the batteries as well.

[dnhz]

I don't think you could get thousands of cycles, but you might be able to go from <500 to ~1000. Higher quality cells might achieve the same thing though. Apple guarantees 1000 cycles on its laptops, like a sister comment states.

Consider a Tesla that gets ~250 miles of range per full cycle. The battery would reach 1000 cycles after 250k miles of driving, at which point you have a pretty old car. Depending on factors like time, environmental conditions, driving style, a battery replacement might be necessary at some point in the car's life. So the batteries in EVs probably cannot sustain thousands of cycles. The battery capacity is large enough that the overall cycle count is reasonable within the lifespan of the vehicle, and the battery cooling system keeps degradation reasonable given the high demands EV batteries must fulfill.

[lathiat]

Apple actually does this both with your iPhone battery and your AirPods but it’s automatic and you can’t ask to switch to that mode. I see it holding my AirPods at 80% overnight quite a bit. They call it “optimised battery charging”.

I use my AirPods so much all day every day I do wish I could ask it to use that mode permanently.

[leucineleprec0n]

You can turn off optimized battery charging. Settings > bluetooth device info > toggle it

[tedunangst]

Alas, a product that lasts five hours for 100 cycles gets much better reviews than a product that lasts four hours for 1000 cycles.

[nomoreplease]

I wonder if this was configurable, if that would get better reviews than both?

[nomoreplease]

Why 80%? Is 100% dangerous?

[numpad0]

Li-ions are charged in Constant Current mode from cutoff voltage(2.75V-3.2V) until maximum voltage(4.2-4.3V), and charged some more in Constant Voltage mode until cutoff current(<0.1C) is reached. Nominal voltage is in the middle at 3.7V.

I believe these (cutoff voltage, CC->CV switch, cutoff current point) are commonly referred to as (0%, 80%, 100%) levels respectively, if safety margins and psychological tweaks are not considered.

Which leads to an assumption that it is this Constant Voltage region that is often said to be damaging to cells, though I don’t know exactly why.

[FredFS456]

Neither 0% nor 100% are dangerous, but lithium ion batteries wear out a lot faster if you cycle them all the way instead of only staying within 20-80%.