
Pull the plug. Your battery will thank you - dmlorenzetti
http://thisweekinbatteries.blogspot.com/2010/02/pull-plug-your-battery-will-thank-you.html
======
BigZaphod
I've had Apple laptops going back to the release of the Titanium PowerBook and
I've almost always used them plugged in for the vast majority of the time and
I've never had this dreaded battery death that articles like this talk about.

However, I have a friend who seems especially apt at killing the very same
batteries in the very same laptop models. My rather uninformed theory is that
there's a specific kind of behavior that adversely affects them - but whatever
it is, I don't do it and he does. I _think_ the key is that he uses his
_without_ power a lot, running it down frequently, etc. which seems to be what
this article is suggesting (and most articles about prolonging battery life
suggest).

Given my own experience, I'm continuously confused at the pervasiveness of
this advice given how counter it is to my own experience - but perhaps there's
some intelligence in the batteries/charger that's protecting me from myself?

I mostly think of my battery as a built in UPS and not as a gas tank.

~~~
nasalter
FYI, Apple have a page providing advice on battery care:

<http://www.apple.com/batteries/>

One of the things it says is...

"Standard Maintenance

For proper maintenance of a lithium-based battery, it’s important to keep the
electrons in it moving occasionally. Apple does not recommend leaving your
portable plugged in all the time. An ideal use would be a commuter who uses
her MacBook Pro on the train, then plugs it in at the office to charge. This
keeps the battery juices flowing. If on the other hand, you use a desktop
computer at work, and save a notebook for infrequent travel, Apple recommends
charging and discharging its battery at least once per month."

~~~
jrockway
_For proper maintenance of a lithium-based battery, it’s important to keep the
electrons in it moving occasionally."_

I knew I shouldn't have set my air conditioner to absolute zero...

------
arghnoname
I have a Lenovo laptop and it has the feature it describes. You can set a
manual charge cut off or do the following:

"Optimize battery lifespan (automatically change for me)"

Right now, it seems to not charge the battery unless it gets under 96% charge,
and then it charges to full. Its language implies that it changes that charge
level based off of a good compromise between battery life and charge. As
someone who doesn't want to think about the battery issue, I really love this
feature.

~~~
pmjordan
Macbooks do the same, but I haven't found a way to change the threshold. 90,
85 or even 80% would be fine for me.

------
mustpax
So, why don't laptops completely bypass the battery when the battery is
charged and the power is plugged in? If the laptop can work when the batteries
are removed, it should be able to cut-off power to/from the battery when fully
charged as well.

~~~
rdtsc
When the laptop is at home, just charge the battery to 50% then remove it so
it works only from the plug. I don't move my laptop as much as I did before
and I noticed that I get much better battery lives than my friends who
continuously keep their laptop plugged in and with the battery attached.

~~~
mustpax
Obviously this is the current solution. I was pointing out that laptop
manufacturers could remove the need for fiddling with your power connection by
automatically disconnecting the computer from the battery when it is not
needed.

~~~
eru
Yes, but you need a way to tell it whether you don't want to use the battery
in a long time (so 50% charge is good), or whether you want to get up and go
on the road soon --- where 100% charging is nice.

~~~
rdtsc
Allegedly Thinkpads have that. But I run Ubuntu on mine so I don't have access
to the fancy bios setting utilities from Lenovo. I just snap the battery out.
That seems to work for me.

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bonsaitree
While correct, I really view this as a non-issue.

I suspect for most people, their in-memory data, time, and attention are far
more valuable than not having power redundancy protection against an
accidental cord disconnect or possible increased degradation on a ~$100
replaceable component on a $1k+ machine--namely the battery.

------
davidw
Huh... that's annoying. 95% of the time, I use the laptop in my home office
and don't really want to mess around with plugging/unplugging it:-/

~~~
yungchin
For desk use, it's best for your battery to remove it from the laptop once
it's fully charged. You don't want to continuously plug/unplug your laptop
because that would just cycle the battery a lot, and that's not good for it
either.

As for me, I usually just leave the battery in: it's a nice UPS, worth the
expense of perhaps a few months of lost life.

~~~
jackowayed
Do you know if one can hot swap batteries (which would also allow simply
removing or adding it) on most laptops that will run without a battery? I want
to try removing the battery from my computer while it's running or putting one
in while it's running, but I'm a little afraid of death.

~~~
altano
If you're laptop is plugged in you should be able to hot swap the battery. If
you're worried about data loss, put your machine to sleep first, wait ~10
seconds, swap the batteries, wake it up from sleep. This is safe even if your
machine loses power totally while swapping out the batteries.

OSX and Windows both support writing out your ram to disk, losing all power,
then resuming from this state exactly where you left off when power is
restored.

It's the default on OSX and may need to be enabled on Windows depending on
your hardware: [http://maximumpcguides.com/windows-7/turn-hybrid-sleep-on-
in...](http://maximumpcguides.com/windows-7/turn-hybrid-sleep-on-in-
windows-7/)

~~~
jackowayed
Yeah, I've done it after hibernating, but hibernating and waking up from it is
like a 3-minute process for me.

It's not data loss I'm afraid of (I always save, even moreseo if I'm doing
stuff that might make my computer turn off), it's like sparks and other such
stuff that can happen when you're dealing with electricity.

~~~
kgermino
I hot swap all the time, even if the computer is plugged in there should be no
problem with sparks or anything like that.

------
niyazpk
Where I stay in Bangalore, we have about 3 one hour power cuts per day. So my
laptop battery is getting good exercise!

------
Zak
The article mentions that Thinkpads come with a utility to set the charging
cutoff point. Has anybody figured out how to do this on Linux?

~~~
yungchin
[http://www.thinkwiki.org/wiki/Tp_smapi#Battery_charge_contro...](http://www.thinkwiki.org/wiki/Tp_smapi#Battery_charge_control_features)

------
yungchin
The article is right, but it's hard to read. If you don't read carefully, it
seems to suggest cycling your battery more, when actually it just suggests not
pushing it near 100% charge too long.

Here's a complete and simple summary of good practice:
<http://batteryuniversity.com/partone-21.htm> (more details on other parts of
that website) - for most geek-apparel, the LiIon column will be applicable.

------
GeneralMaximus
I've had my MacBook for 1.5 years now, and my battery life is still a little
more than 4 hours. I keep my machine plugged in all the time, and completely
run it down once a month. On the other hand, my friends who have the same
MacBook have terrible battery lives. They use the laptop on batteries all the
time.

I'm inclined to believe this guy has no idea what he's talking about.

------
nazgulnarsil
simpler solution than constant plugging and replugging for me was to remove
the battery if I'm not going to be moving the laptop for an extended period.

~~~
chops
It's nice having that battery as a UPS though, in the event of an outage.

------
DanielStraight
I always knew you shouldn't leave your laptop plugged in all the time, but I
never really knew why, and my subtle misunderstanding was actually harmful. I
thought the issue was just that sometimes you needed to let the battery drain
and recharge it from a drained state. That's not very helpful though if the
rest of the time you're running at full voltage. Thank you for the submission.
Great article.

------
ANH
Over the past four weeks my Macbook Pro battery's performance declined
precipitously, and I think this is the cause. I tended to leave it plugged in
whenever I was at my desk, which is most of the time. Got to the point where
the MBP wouldn't last more than 5 minutes unplugged. Just received a new
battery and all is well. Think I'll be giving this technique a shot.

------
jockc
Seems like it would be easy for laptop makers to design something into the
laptop to manage how the battery charges/discharges when it's plugged in. That
way you could leave it plugged in 99% of the time (as probably many of us do)
and not impact the battery negatively.

------
lftl
Interesting... sounds like an interesting application for this idea:

[http://www.unplggd.com/unplggd/green-ideas/leech-plug-
unplug...](http://www.unplggd.com/unplggd/green-ideas/leech-plug-unplugs-
itself-after-it-completes-a-charge-108847)

------
sounddust
Newer Sony laptops come with "Battery Care" software that automatically keeps
the battery between 50 and 80% at all times. According to Sony engineers, a
battery that is always kept at or below 50% will essentially never degrade in
capacity.

~~~
there
so what's the point of having a big battery then if it never charges to 100%?

~~~
sounddust
Well, it's still more battery life than a small battery that never charges to
100%, right? I think regardless of the battery size, you can make the decision
to preserve the long-term life of your battery or have the extra capacity in
the short-term.

Plus, charging from 20 to 80% is much faster than charging from 20 to 100% (I
estimate that about half of the time is spent just going from 80 to 100).

------
sailormoon
I killed 2 macbook pro batteries in 2 years by not following this advice. Now
I make sure to unplug and carrying around the laptop whenever I can.
Eliminating all wired peripherals was a key step to actually doing this in
practise.

~~~
lutorm
I thought the MBP battery switched off charging when it was full, so that it
charges up the battery and then disconnects it if you are plugged in. When the
battery has self-discharged some amount, it tops it up again. But maybe I
misunderstood.

The flipside, though, is that Li-ion batteries also age from discharge cycles.
So I really don't think it's better to run the battery down, charge it up, and
repeat. The number of charge cycles is limited, so I bet that will kill it
faster. If you really want to save the battery, you can take it out and put it
in the fridge when you are plugged in.

~~~
jonknee
> If you really want to save the battery, you can take it out and put it in
> the fridge when you are plugged in.

Unfortunately MacBook Pro batteries are not removable anymore. That really
grinds my gears.

~~~
moe
Well, technically you can and it doesn't look too hard:
<http://www.youtube.com/watch?v=42qcvlftmcM>

But it seems apple is not officially selling those batteries, which makes _my_
gears grind. I don't want to walk to an apple store or send my laptop away
just to have the batter swapped.

