Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Apple changes default MacBook charging behavior to improve battery health

sixcolors.com

Post reply on HN
Print view View original

221–230 of 386 posts

Re: Apple changes default MacBook charging behavior to improve battery health

#221

Post by proverbialbunny »

satysin wrote: post #101
rubber_duck wrote: post #53

I got a top spec 15 MBP a year ago and I have to say the experience is appalling - 4000$ device that goes full airplane takeoff levels of noise at any serious workload, no ability to control performance (I would gladly throttle the CPU sooner to avoid everyone in the office turning my way when I start an emulator or keep the fans at lower RPM but constantly instead of letting the CPU idle at 60-70 degrees with no fan…

I have almost identical spec laptops from Dell and Apple (XPS 15 and 15" MacBook Pro with same CPU) and on both they ramp up to full fan speed when I do any serious work on them so it isn't limited to Apple laptops. Pretty much all 15" laptops with 45W Intel CPUs turn into jet engines when under load, at least in my experience. Also not to defend Apple but I do find the MacBook Pro cools down and gets quieter quicker…

>Also not to defend Apple but I do find the MacBook Pro cools down and gets quieter quicker than the Dell does although that could down to my personal setup

Apple tunes itself to spin down it's fans later, which is why you're noticing this.

This is because when the average user runs a cpu intensive task it is unlikely you will run another one seconds later, so the cpu can cool off without all the fan noise.

Re: Apple changes default MacBook charging behavior to improve battery health

#222

Post by aeyes »

diebeforei485 wrote: post #136

So many people on here seem to be intent on micromanaging their device's battery. IMO the whole point is to let macOS handle it so you can focus on actual work. I know Apple has screwed up in the past with throttling iPhone CPU's (bad). At this point they know not to go to those lengths again.

Would be nice if that worked though. I have a 2 year old MacBook with a dead battery, turns off anywhere between 40 and 60% after about 1 hour of use.

Until they come up with something that actually works I'd be grateful to be able to set a lower max charge if I know that the device is mostly used plugged in. And since nobody has been able to come up with anything in over 10 years of dead batteries from devices which are always plugged in, I doubt that this will be resolved anytime soon.

Re: Apple changes default MacBook charging behavior to improve battery health

#223

Post by supernova87a »

copperx wrote: post #85
wrs wrote: post #42

I've noticed that on newer (past few years) MacBook Pros, if their battery runs down too far they refuse to start up, even when plugged into the charger. The battery has to charge for 10-15 minutes with the "dead battery" icon on the screen. It's exactly the same behavior as iPhone/iPad. In past MacBook models, the battery could be dead--or even completely removed--and the charger would power the laptop fine. Anyone…

This is the most irritating thing about the iPhone. Phone shuts down in the middle of an important call? Sorry, you'll have to wait 15 minutes before you can call again. This doesn't happen in my Pixel phones. Plug it it, turn it on. I would be irritated to no end if this happened to my laptop.

Well here's the challenging thing -- your phone may be way overdue for a battery replacement, or you've run your phone like this well over the average user -- so it's been doing this to save you from having no phone at all. But you don't credit Apple with the 2nd part, and blame it for the 1st part. It's tough to make something for customers, huh?

Not making a personal jab at you -- just illustrating the difficultly that everyone who makes a product faces when managing user expectations.

Re: Apple changes default MacBook charging behavior to improve battery health

#225

Post by aeyes »

floatrock wrote: post #115
atombender wrote: post #104

Earlier quoted context omitted.

It's my understanding that modern EVs like the Kia Niro EV or the Chevy Bolt work this way. When nominally charged to 100%, the actual charge is closer to 80%. A 75 kW battery will typically only go to 64 kW.

During one of the last few hurricanes, Tesla did an OTA update that unlocked extra range for people trying to leave. I seem to remember it being something like the hardware capacity is one number but there's a software upsell that you normally need to pay to unlock full capacity. But it may have also been a "we'll push the normal operating parameters to give you this extra boost", don't quite remember.

Tesla has a very minimal top buffer though, it is only used to offset the known degradation of the new battery. After 6-9 months you'll have no top buffer left. You can tell because charging from 99 to 100% is at extremely low amps and takes forever.

Re: Apple changes default MacBook charging behavior to improve battery health

#226

Post by aeyes »

Nyra wrote: post #193
mr_toad wrote: post #153

Earlier quoted context omitted.

Generally speaking it’s better to keep it plugged in than to repeatedly charge and discharge it. But it’s even better to keep in plugged in at 80% charge instead of 100%.

Really? I'm not very knowledgeable about the subject but I always understood that discharging the battery was healthy. Is there somewhere I can read up on why that is?

It is healthy, but discharging to 0% isn't and keeping it at 100% isn't either. It is best to plug in at 20% but only charge to 80%. Then every half a year you do a full charge to 100% and a full discharge to calibrate the battery management.

But sadly that can't be configured on a MacBook.

Re: Apple changes default MacBook charging behavior to improve battery health

#227

Post by aeyes »

m_eiman wrote: post #47
aeyes wrote: post #19

Just let me set a max charging percentage like on my Thinkpad please.... After 2 years the battery on my MacBook Pro is pretty much dead.

You should probably check your battery cycle count: https://support.apple.com/en-us/HT201585

Its around 350, the battery is dead from being plugged in at work 10-12 hours every day.

Re: Apple changes default MacBook charging behavior to improve battery health

#228

Post by ken »

wrs wrote: post #42

I've noticed that on newer (past few years) MacBook Pros, if their battery runs down too far they refuse to start up, even when plugged into the charger. The battery has to charge for 10-15 minutes with the "dead battery" icon on the screen. It's exactly the same behavior as iPhone/iPad. In past MacBook models, the battery could be dead--or even completely removed--and the charger would power the laptop fine. Anyone…

My initial guess was MagSafe, since that’s where I first saw it. With a breakaway cable, it’s less likely you’ll be able to keep a solid power connection.

I’m a little bummed to learn that this apparently isn’t the (only) reason.

Re: Apple changes default MacBook charging behavior to improve battery health

#229

Post by fulafel »

atombender wrote: post #104
cmckn wrote: post #80

Why doesn't the UI report 80% as 100%? It seems like exposing this to the user is more confusing than anything, when the cells could be over provisioned and treated politely by a system controller, without the user being part of the decision. Aren't SSD's over provisioned in this manner? You sell a drive with a terabyte of storage, but actually ship more than a terabyte of chips in the case to accommodate degradation…

It's my understanding that modern EVs like the Kia Niro EV or the Chevy Bolt work this way. When nominally charged to 100%, the actual charge is closer to 80%. A 75 kW battery will typically only go to 64 kW.

All li ion batteries work this way. If the battery mapped 100% to the chemical max capacity, your batteries would degrade very fast and die very young.

This whole discussion is colored by confusiin between the heavily simplified model presented by the charge indicator with the raw battery properties.

Fun fact: there is no "80%" level either as seen from the battery controller POV, that's just a forecast about how much energy the battery might be able produce if run until the cut-off level (and the 0% level here is also a fair bit above the chemical empty state), and the battery controller is constantly updating its model about how the battery behaves when discharging to keep the forecast accuracy reasonable when the battery ages. When the batteries come from the factory, the calibrations for 0%, 80%, 100% are at certain voltages, and they constantly move throughout the life of the battery. (Maybe not the 0% voltage)

Re: Apple changes default MacBook charging behavior to improve battery health

#230

Post by NickNameNick »

outworlder wrote: post #143
chipotle_coyote wrote: post #129

Earlier quoted context omitted.

> Why doesn't the UI report 80% as 100%? Because the last time they tried "silently manage the battery without the user being part of the decision" it didn't go over real well?

That wasn't even managing the battery, per-se(although it is power management, it wasn't strictly about health). It was reducing clock speeds to extend the amount of time the device would be on. They still do it even if the device has a healthy battery: drain the phone to 1% and you will see. Rather than running at full blast and shutting down, you can extract more runtime. Some EVs do something similar: the Nissan L…

The problem was the phones battery couldn't deliver enough current to run the cpu at full power, even though it had charge remaining to run the phone for some period of time in a lower power mode.

Without power management, when a high demand task came alone and the CPU tried to draw more power, the phone would crash or shut-down.

The firmware update capped performance not to extend the run-time when the batteries were low, but to allow the phone to run reliably when the batteries were worn.

Post reply on HN