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Ask HN: Should I unplug my laptop charger at 100%?

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Re: Ask HN: Should I unplug my laptop charger at 100%?

#221

Post by rkda »

bluedino wrote: post #26

Lenovo at one time (they still might, I'm not sure) included a piece of software that allowed the user to optimize charging for battery life. Basically, it would stop the battery from reaching 100% of a charge. Great idea, except that if you forgot to turn this feature off and had to leave, you might leave the house with just 60% battery life.

I'm using a Lenovo now and they still have it. Old Samsung also had something similar, Battery Life Extender, which won't stops charging at 80% even when plugged.

Re: Ask HN: Should I unplug my laptop charger at 100%?

#222

Post by rkda »

BorisMelnik wrote: post #123
sigmar wrote: post #114

Earlier quoted context omitted.

>plug in and let charge to 90%, unplug and use for a couple of hours, plug back in at 50% or so, rinse and repeat. My thinkpad has a mode for keeping a healthy battery that stops charging at 90%, then trickle charges to keep it there (it also allows for fine tuning of this behavior)

excellent - what software does this? Built into the OS or a separate application?

From experience, it's a separate app but manufacturer specific. Haven't had much luck looking for a generic app.

Re: Ask HN: Should I unplug my laptop charger at 100%?

#223

Post by SmellyGeekBoy »

IE6 wrote: post #152
silverlake wrote: post #126

Earlier quoted context omitted.

My Sony VAIO had this 7 years ago.

Yeah my thinkpad did this from the same vintage but that was only on Windows. I think quality of battery management on other Operating Systems is varied...

My ThinkPad E530 (1 year old) has this, it's part of Lenovo Power Manager. Again, only on Windows (it doesn't charge at all in Ubuntu, which I've never managed to get to the bottom of)

Re: Ask HN: Should I unplug my laptop charger at 100%?

#224

Post by cgabios »

ChristianBundy wrote: post #213
jffry wrote: post #173

Earlier quoted context omitted.

running ioreg -l -n AppleSmartBattery -r | grep -i capacity gives me "MaxCapacity" = 8329 "CurrentCapacity" = 8002 "DesignCapacity" = 8440 I'm guessing MaxCapacity or CurrentCapacity (I'm at 100% charged on a ~1 year old MBP, so I don't know which number is appropriate)

Your battery percentage is going to be: 100 / DesignCapacity * MaxCapacity Or, in the way that makes way more sense to me: MaxCapacity / DesignCapacity * 100 Which, with your results, yields something to the effect of: 98.68% It's kind of (read: very) dirty looking, but you can get the same result with: echo $(ioreg -l -n AppleSmartBattery -r | grep MaxCapacity | awk '{print $3}') / $(ioreg -l -n AppleSmartBattery -r…

    ioreg -l -n AppleSmartBattery -r | awk '/MaxCapacity/{mc=$3};/DesignCapacity/{dc=$3};END{print 100*mc/dc}'

Re: Ask HN: Should I unplug my laptop charger at 100%?

#225

Post by cerberusss »

mangeletti wrote: post #137

Personal experience: I'm on an early 2011 MacBook Pro (purchased in March, 2011), which I've used for about 8-10 hours per day, 5 days per week, since the date I purchased it. I have about 6.5 hours remaining at a 91% charge (screenshot for proof http://cl.ly/image/1a2d2y2V1J2O ). I consider this to be pretty good for a notebook that has been used extensively for more than 4 years, which is why I felt like I should s…

One disadvantage is that you miss all Power Nap features: https://support.apple.com/en-us/HT204032

In my opinion, you don't miss all that much except for the following features: * Software updates download * Time Machine performs backups * Spotlight perform indexing

Re: Ask HN: Should I unplug my laptop charger at 100%?

#226

Post by cerberusss »

polyx wrote: post #151

IMO, I dont really care about it that much. You will probably want to change laptop after 2 or 3 years anyway, during this time battery degradation should not be a massive issue.

Exactly, that's my method as well. Although I have to say it's not so much a necessity rather than a preference for new and shiny. Hardware is so powerful nowadays.

Re: Ask HN: Should I unplug my laptop charger at 100%?

#227

Post by moopling »

hsitz wrote: post #165
rexf wrote: post #120

Earlier quoted context omitted.

I agree with you. Instead of optimizing for battery life by constantly checking & adjusting my charging, I'd rather live my life focusing on other things. What I do is super simple: plug it in whenever possible.

Same here. I have no reason to dispute the expert who says Lithium-ion batteries "don't love 100%". Fine, but they don't seem to dislike it too much, either. So far I haven't had any batteries that didn't perform well when they were mostly plugged in, occasionally discharged in mobile use. I see some similarities to, e.g., medical pronouncements that some particular food increases risk of cancer. It's easy to get ala…

I get what you're trying to say, but there's an interesting point to be made here about absolute vs relative risk: imagine for instance your absolute chance of getting cancer was less than 0.0005%

Re: Ask HN: Should I unplug my laptop charger at 100%?

#228

Post by hurin »

sokoloff wrote: post #212
hurin wrote: post #102

Earlier quoted context omitted.

I'm not a hardware/electronics guy, but I'm rather skeptical that this is any kind of notable amount - do you have a reference?

Put the back of your hand (or your bare leg skin) against a laptop that's been in use. My Macbook is noticeably warm (maybe 15*F delta) in normal, non-charging, operation. That's with the benefit of conduction to the free air; I assume the inside delta-T is higher.

That's not answering my skepticism to GGP's post - what he is saying is: a non-charging plugged in device has a significantly hotter battery than a non-plugged in device because of thermal-conduction across a non-charging wire?

Re: Ask HN: Should I unplug my laptop charger at 100%?

#229

Post by critiq »

cgabios wrote: post #224
ChristianBundy wrote: post #213

Earlier quoted context omitted.

Your battery percentage is going to be: 100 / DesignCapacity * MaxCapacity Or, in the way that makes way more sense to me: MaxCapacity / DesignCapacity * 100 Which, with your results, yields something to the effect of: 98.68% It's kind of (read: very) dirty looking, but you can get the same result with: echo $(ioreg -l -n AppleSmartBattery -r | grep MaxCapacity | awk '{print $3}') / $(ioreg -l -n AppleSmartBattery -r…

ioreg -l -n AppleSmartBattery -r | awk '/MaxCapacity/{mc=$3};/DesignCapacity/{dc=$3};END{print 100*mc/dc}'

mine is at 103.211

Re: Ask HN: Should I unplug my laptop charger at 100%?

#230

Post by mauz0r »

bluedino wrote: post #170
johnymontana wrote: post #167

Earlier quoted context omitted.

Could you clarify how you arrived at 84% battery health? After the command "ioreg -l -n AppleSmartBattery -r" I see DesignCapacity, but where does the other number (5629) come from? I'd like to compute battery health myself...

He's just dividing the current battery capacity by the 'new' battery capacity. You can just let a program like Coconut Battery do it for you.

Coconut Battery is nice. You can let it take snapshots and compare it with other batteries online. You can view my battery health here http://ccbonline.coconut-flavour.com/index.php?bid=d78a6c124.... I try to unplug at 100% and recharge it at 10-20%. Once per month I drain it all the way to 0%.

After reading this thread I try to keep my battery at a 50-80% charge :)

Except when I do some CPU intensive stuff like compiling or rendering, then it is being charged thought the process.

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