The life and death of a laptop battery
people.skolelinux.org
people.skolelinux.org
http://superuser.com/a/664583/32370
This is probably because of some sort of planned obsolescence - they want you to replace your device.
On the other hand, in electric cars (using the same battery chemistry), where it is in the company's best interest not to replace the battery, it is charged to a maximum of 70-80%, except when soaking up extra energy going downhill, and basically maintains its full capacity for much longer.
My Samsung has a BIOS setting to limit charging to 80%.
Practically speaking, even assuming my battery did idle at 50% sitting on my desk, what happens when I decide to take it out to the coffee shop (or the airport!) and want it at 100%? I don't want to micromanage charging my battery and filling it up before I go out. I have enough fun discovering my car is only ever out of gas when I'm about to depart on a long drive.
my 4 year old iphone 4 got 3 days on a single charge when I got rid of it.
My year old 6 still gets 2-2.5 days per charge.
When I disconnect the charger I have seen estimated battery remaining times of anything from 2 hours to 87 hours! However in reality it's more like 45 minutes :(
Do a full battery cycle at least once a month and you won't prevent the catastrophe.
Source: http://batteryuniversity.com/learn/article/how_to_prolong_li...
Storing a battery at 40 degrees C at 100% charge will degrade it by 35% after a year. Drop that to 25 degrees C and it'll be degraded by only 20% after a year. If it was stored at 40% charge instead of 100% charge that drops to only 4% degradation after a year.
My 3.5 year old Asus laptop has still similar battery life as it had when it was new. I always keep it on the charger when I can and sometimes I just shut it down and leave it on the charger overnight too (but this is rare). When I bought it, I have noticed that the battery was never above ~95%, but I have never studied how it works exactly (is it done by HW or by the driver). I have used it with Win7, Win8, Win8.1 and now Win10.
e.g. it's very obvious that Macbooks have multiple different charging regimes, and they use different ones depending on what the laptop's doing and the state of the battery.
"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 between uses"
Keeping the battery constantly at stable 60-80% charge is far better than doing full discharges every month.
Does anyone know of any good power management software for Linux? I am about to get my first Linux laptop and this is one of my primary concerns (since the laptop is designed for Windows 10).
They do the same thing you or I do before ordering a laptop we intend to throw Linux on: do some research first to find one that is mostly compatible, and then tweak the hell out of it until it mostly works. They just take the extra step of then selling the laptop. However, I can tell you from personal experience that System76 Linux laptops are far from perfect Linux experiences.
My Lenovo laptop has been plugged in for the last 3.5 years, only very occasionally (once a month?) going on battery power for short periods of time. Windows reports that I still have 91.7% of the design capacity. I'm not sure if I should trust that number or not... but the last time I unplugged it, the battery seemed to last at least 70% as long as it did when it was new, so it's not totally off, either.
Windows 7 can also generate power reports (powercfg -energy) but it's a little less human friendly
Unfortunately for me it appears that installing windows 10 reset the stats, as my report only goes as far back as about a week after I installed windows 10.
Did someone follow the link to the Macbook Air? It shows that the Mac battery lasts much longer than the Thinkpads. My impression is similar: my Thinkpads (back when IBM still labelled them) where down after 2 years. All Powerbook or Macbook batteries that I ever had still did well even after 3 years.
Shocking, on the other hand, is the amount of detail of the battery usage records that apple stores. Imagine apple had access to them.
Bought Nov 2013, now has over 250 charge cycles and is still at 90% of original capacity.
This would be similar to what SSD manufacturers do with drive sizes. There are more memory cells on the die than the sticker capacity, and as cells fall out of use (due to failure or maximum number of write cycles) extra cells are rotated into use to maintain speed and capacity.
To answer with my own anecdote, my three year old thinkpad has had barely any drop in capacity, whereas a friends macbook pro of a similar age has only about 60% of its original capacity.
It's hard to compare these things because it depends so heavily on usage patterns.
My 2006 MacBook still holds about 30 minutes of charge in the original battery. Most of the time I left it plugged in all the time, what do people do that kills them so quickly?
After about a year, there has not been a noticable degradation in battery life (and I have noticed it in past laptops).
But dead batteries are what keeps the economy spinning, so it must be in all our best interest that the self-optimizing algorithm of capitalism decidedly skips on this particular efficiency gain, right?
If the full contents of a 16GB memory are written to disk for hibernation daily, with say another 50GB of work, that's over 6 years before you hit the lower limit. I probably wouldn't trust a hard disk that was used that heavily for that long either.