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Unplug Your Laptop Now, or It Will Stay Plugged in Forever

gizmodo.com

21–30 of 73 posts

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#21
Apple took this out of Mac OS somewhat recently. You can try to rely on their power management, but given battery decay is a common reason to buy a new machine I don’t trust them really.

If you have an Apple Silicon Mac I can recommend Battery [1]. It can keep your Mac at 80%, and even force discharge while plugged in to get there. It’s a CLI and status bar utility, I love it.

[1: https://github.com/actuallymentor/battery]

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#22
post #6

Somewhere down the line, many of us got the idea that our laptops should always be plugged in to improve their performance Because the manfacturers made the firmware defaults downclock the CPU if it was on battery power. Also, is it just me or does this article have an "AI generated" feel to it? The arguments it makes are somewhat in the "uncanny valley" between truth and fiction, and the phrasing of some of the sent…

Yeah, this does seem AI generated, or at least “AI assisted” in that it was primarily written by AI and a human slightly modified it and then stamped their name on it. Just look at this paragraph: “Many laptops sit on a charger throughout the workday and all through the night. We don’t even think about it; we just plug in everywhere. We’re charging at work, at home, at the coffee shop – a collective addiction to a la…

But I feel like LLM wouldn't make such non-sensical content, unless they used some obscure LLM.

The article is over dramatized causing false statements, doesn't use any of the usual GPT4 lingo etc.

E.g. claiming that it is the "worst thing you could do".

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#23
The article doesn't explain the why here... it's because 2 things impact lithium ion lifetime - voltage (both high and low) and temp.

"In terms of longevity, the optimal charge voltage is 3.92V/cell."

https://batteryuniversity.com/article/bu-808-how-to-prolong-...

That maps out to roughly 65% charge state.

There's a great app called AlDente for MacOS that allows you to set the charge limit while plugged in.

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#24

Is there a good reason why we can't tell our devices to charge the battery to say 70% and then internally disconnect the battery, so it's neither charging nor discharging?

Dell laptops have had such a feature literally for a decade now

That's good to know, I guess I'm curious why it's not (nearly) ubiquitous. Does it add significant cost and complexity to hardware design?

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#25
post #8

Please explain like I'm five: if continuously charging and drawing power at 100% hurts my laptop's battery, why doesn't the laptop bypass the battery circuitry, keeping it idle, and use the incoming juice directly?

Probably, most of the charge controller chips don't have that feature or it costs more to implement than the OEMs want.

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#26
I can confirm from my own experience that this happens.

First laptop at work, always plugged in (except for maybe one or two hours a week). After two years of use (maybe a couple more from a previous employee) the battery lasted 30 minutes.

Personal laptop. Mostly plugged in (except when traveling maybe 3-4 weeks per month) but with the charging at 80% capped (it's an option from the manufacturer). Almost 10 years later still holds around 1-2 hours (disclaimer: I don't use this laptop anymore except for occasional tests)

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#27
post #8

Please explain like I'm five: if continuously charging and drawing power at 100% hurts my laptop's battery, why doesn't the laptop bypass the battery circuitry, keeping it idle, and use the incoming juice directly?

It does, if the battery is 100% no more charging current goes in, so charging stops.

But the key point is that the battery will drop to 99% very quickly and on it's own because no battery can keep the energy in perfectly. So it's recharged for the missing 1% over and over again which causes the damage.

Unless some smart charging logic prevents that, see other comments here.

Edit: typo

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#28
My previous Intel MBP which I've used for every day charging to 100% and discharging to 20% or so has 600 cycles now, battery health is at 81% and has been hovering there. It's still fine, but my point is if you think of relying on applecare+ to replace your dead battery, they will only do so if it's under 80% reported health and my conspiracy is that there's some reported value stickiness around 80%, it will have to be really bad for it to go below, and without it going below no applecare+ replacement.

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#29
post #8

Please explain like I'm five: if continuously charging and drawing power at 100% hurts my laptop's battery, why doesn't the laptop bypass the battery circuitry, keeping it idle, and use the incoming juice directly?

The issue is high voltage state and temp are bad for lithium ion batteries.

"In terms of longevity, the optimal charge voltage is 3.92V/cell"

https://batteryuniversity.com/article/bu-808-how-to-prolong-...

That maps out to roughly 65% charge state. So a little trickle charge on/off doesn't really help things much at all. You simply need to keep the battery in a lower charge state while plugged in for longer periods.

As bad as this is alone, the toxic combo that kills a plugged in laptop's battery in a year or two is regularly pushing it hard at full charge.

Re: Unplug Your Laptop Now, or It Will Stay Plugged in Forever

#30
post #27
post #8

Please explain like I'm five: if continuously charging and drawing power at 100% hurts my laptop's battery, why doesn't the laptop bypass the battery circuitry, keeping it idle, and use the incoming juice directly?

It does, if the battery is 100% no more charging current goes in, so charging stops. But the key point is that the battery will drop to 99% very quickly and on it's own because no battery can keep the energy in perfectly. So it's recharged for the missing 1% over and over again which causes the damage. Unless some smart charging logic prevents that, see other comments here. Edit: typo

It's not just this, it's literally bad to keep a lithium ion battery in a high voltage state, period. Simply taking a battery out and leaving it on the shelf in a high voltage state, otherwise unused, harms it.
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