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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%?

#231
post #58

Source: I have a master's degree in mechanical engineering in hybrid vehicle powertrains, and a big part of my research was battery technology. I spent some time working with the folks at National Semiconductor learning this, so I have several primary sources. Disclaimer: my knowledge of the field is from ca 2010. 1) Lots of deep discharge cycles do negatively affect battery life. Try not to jump between 0% and 100%…

> plug in and let charge to 90%, unplug and use for a couple of hours, plug back in at 50% or so

Well isn't this what computers are good at? I thought modern computers had a microcontroller for doing this...

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

#232
From the Help and Support for the ThinkPad X201 Tablet:

  To maximize the life of the battery, do the following:

    Use the battery until the charge is completely
    depleted--until the battery status indicator starts
    blinking orange.

    Recharge the battery completely before using it. 
    The battery is fully charged if the battery indicator
    shows green when the AC adapter is plugged in.

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

#233

Earlier quoted context omitted.

Time to write an app to do that (possibly only for rooted phones), someone?

That's assuming that devices don't already operate in this range of SOC within device...which I wouldn't believe to be true.

Yes, I didn't (/don't) know about that. I believed the charging cycle would have become intelligent by now, but thought then this whole thread wouldn't come up if that was the case.

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

#234
post #120

Earlier quoted context omitted.

That's nice to know. However, i'd rather buy a new battery after 5 years (if my laptop is still fit and the battery is dead), than having to complicate my life and think about when to unplug or charge my laptop multiple times each day for 5 years... My Macbook air from mid 2011 is currently at 100/6700*5629 = 84% battery health. (6700 = design capacity, gathered from "ioreg -l -n AppleSmartBattery -r".

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.

A ThinkPad takes care of everything https://forums.lenovo.com/t5/image/serverpage/image-id/10659...

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

#235

Earlier quoted context omitted.

Could you elaborate on how you arrived at the "5 years" lifespan for batteries having charge state of 0-100%?

That was just a personal estimate, obviously if the battery health is for example at 75% you also lose 25% of 'the time' to work without plugging it in... so if that becomes a problem when traveling i might want to buy a new one. For others this might not be a problem of course.

Ok. I was wondering if the breakeven is set as 5 years but if the cycle of tilt to full makes the life shorter for the battery, then it may not be worth it. I agree that if I've to weigh battery life vs my time, I would go with the latter.

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

#236

Earlier quoted context omitted.

Is your machine even operational? My macbook air from 2011 (with Yosemite) is sluggish to the point of being unbearable to use and just collects dust.

Mid-2010 MBP upgraded with SSD runs perfectly on 10.10.3

Same here, only boots extremely slow (I have the original HDD but 8gb memory)

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

#238
post #237

Wrote a small script to easily put my Thinkpad battery to storage mode (50-70% SOC) and back to full charge: https://gist.github.com/cmavr8/204132a008d4ebabce94 Also one (lame) for bat stats on linux: https://gist.github.com/cmavr8/bdf591d8dc66290ae87a

They're not well tested but seem to work. Let me know if you have improvement suggestions that are easy to do.

Chris

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

#239
post #111
post #106

Earlier quoted context omitted.

Assuming your computer has a replaceable battery, which is not the case always. Replacing a $80 battery is worth it to avoid stress, but replacing a $2000 ultrabook may not be.

I would think your ultrabook would be past its manufacturer's warranty anyway at that point anyway and would be a candidate for some sort of DIY battery replacement.

Isn't battery warranties usually 1-year long? A device would have minimum 2-year warranty in Europe so you can find yourself in the middle...

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

#240
post #47

Consider the cost of a replacement battery and if it's worth the subconcious mental strain this consideration places on you. In short, leave it in because it's not worth worrying about.

seriously, i can get a battery for my T410 for ~20$ on amazon, i'm not going to spend my time plugging and unplugging.

Sure, but do you know what cells these batteries use? They're usually cheap chinese ones, of less than half the rated capacity. A proper replacement will cost much more.

I did go mid-way, buying high quality Japanese cells and installing them in a chinese pack. A bit cheaper than a new official battery, but required some work.

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