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.
Ask HN: Should I unplug my laptop charger at 100%?
151–160 of 249 posts
Re: Ask HN: Should I unplug my laptop charger at 100%?
#152Earlier quoted context omitted.
So what my laptop should do automatically is to stop charging once it hits ~90%, and start charging again when it hits ~40%. And the OS should give me an easy-to-reach option to "charge to 100%" for when I'm about to make a trip. Why hasn't anyone implemented this yet?
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...
Re: Ask HN: Should I unplug my laptop charger at 100%?
#153Source: 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%…
What if you're mostly using the laptop near a power outlet? Wouldn't it be better to keep it plugged in to avoid charging/discharging the battery at all?
Re: Ask HN: Should I unplug my laptop charger at 100%?
#154Supposing it would matter, why wouldn't laptop manufacturers include some 0.01$ part that switches off the charger as needed?
Re: Ask HN: Should I unplug my laptop charger at 100%?
#155Earlier quoted context omitted.
Why don't device manufacturers code this kind of thing into their power/battery drivers?
Is it possible they do, and the battery level indicator you're looking at is lying to you?
This is definitely the case for the Prius, even from 2004. I really doubt higher-end manufacturers like Apple wouldn't do the same since they control the entire stack.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#156Earlier quoted context omitted.
Why don't device manufacturers code this kind of thing into their power/battery drivers?
Is it possible they do, and the battery level indicator you're looking at is lying to you?
I don't know, but there seems to be not very much incentive to invest a lot of R&D dollars on this problem from a manufacturer standpoint:
* Devices marketed on how long they last on a single charge, but much less often on how quickly the battery degrades * Batteries are a later upgrade upsell opportunity * I would not be surprised to learn that a significant number of device upgrades start as simply wanting a better battery (but why not upgrade at the same time)
Re: Ask HN: Should I unplug my laptop charger at 100%?
#157Source: 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%…
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".
Just another data point: I'm at 77% (4431/5770) on an April 2010 MBP. I tend to leave it plugged in when possible, and often run it far down when not near an outlet. I take it that's about the worst I can do, but the convenience has seemed worth it.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#158Source: 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%…
The Thinkpad power manager mentions the issue and comes with different modes to maximize the battery lifespan.
Quote: "If you primarily use your computer with the AC adapter attached and only infrequently use battery power, battery deterioration may occur faster if the battery is constantly charged at 100%. Lowering the charge thresholds for your battery, periodically resetting the battery gauge, using Maximum Lifespan mode, or using Battery Health Mode will help increase its lifespan."
Re: Ask HN: Should I unplug my laptop charger at 100%?
#159Source: 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%…
Exceptional. Armed with this info, this will surely save me a ton of money over time, especially if I can get my employees to adopt this reasoning. I've been dying for this answer for years now.
Having an employee micromanage this will actually cost you more money over time.
Re: Ask HN: Should I unplug my laptop charger at 100%?
#160Earlier 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".
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.
Define unbearable. Up until 10.10.2 the OS X window server was a bit sluggish. Now it's tolerable for my purposes.