Personal experience with IPAD 1, 4 years using it every day with full discharges every day more than 1,000 charge cycles.
When new full battery lasted 9 hours after 4 years lasts 8 hours.
Ask HN: Should I unplug my laptop charger at 100%?
41–50 of 249 posts
Re: Ask HN: Should I unplug my laptop charger at 100%?
#42You should unplug it before it reaches 100% unless you know you'll need the full charge. Letting the battery sit at 100% wears it out more than sitting at 40-80%.
It's correct that you'll retain battery capacity better if you store it at 40-80%. But that recommendation is based on long-term storage.
It's not right to assume that also applies to in-use products, especially the way people use them. In fact you'd likely reduce battery life because you're putting the battery through a greater depth of discharge (DoD). Assume you let it run from 80% to 60%, you've just gone through a cycle of 20% discharge when you could have kept the DoD at 1%. Also, most modern laptops will run on power once charged, so it's not like an infinite number of 1% cycles.
http://batteryuniversity.com/learn/article/how_to_prolong_li...
Re: Ask HN: Should I unplug my laptop charger at 100%?
#43Lenovo 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.
Yep - I have this on my Lenovo.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#44You should have talked to Google, instead of numerous people. http://batteryuniversity.com/learn/article/how_to_prolong_li... Summary: Similar to a mechanical device that wears out faster with heavy use, so also does the depth of discharge (DoD) determine the cycle count. The shorter the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often…
This link from google says otherwise.
https://answers.yahoo.com/question/index?qid=20130825212946A...
Lithium ion batteries do seem to have memory.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#45I hate to sound like an ass, but I think I need to say something anyway... Is this the kind of question we want at HN? It's been done to death elsewhere, and is easily answered with a quick search.
I know there can be a fine line between a good, thought-provoking question and a useless one, and, to me at least, this seems too far on the "useless question" side of things. It's about basic hardware maintenance, and I'm honestly surprised it's gotten 37 points in 22 minutes (so far).
Re: Ask HN: Should I unplug my laptop charger at 100%?
#46[deleted]
Re: Ask HN: Should I unplug my laptop charger at 100%?
#47Consider 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.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#48Maybe I have bad luck, but I came to accept that every laptop battery eventually becomes a UPS for getting from the desk to bed :-)
Re: Ask HN: Should I unplug my laptop charger at 100%?
#49You can control the battery % at which a device will begin and stop charging - so there's no need for this. Idk what all this misinformation is about.
Sure, but the battery gets heated when left plugged in, which is not good for its health.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#50I'm an electrical engineering student who needed an idea for a school project dealing with reliability.
I think I just found my project. Stay tuned!