Friday, April 19, 2013

Laptop batteries: WTF?

I'm very frustrated by the mixed messages I'm getting about laptop batteries.

My recent computer troubles turned out to be due to my battery being dead (which involved a weird and roundabout diagnosis!).  All three Dell techs I spoke to in the process told me that you shouldn't keep your laptop plugged in all the time (which I normally do because most of the time I'm using it at my desk), you should instead allow your battery to discharge fully and then recharge it.

However, Dell's laptop battery FAQ says this is unnecessary and the battery will behave nicely even if you leave it plugged in all the time.  But their Alienware battery FAQ says the opposite. 

I did start charging and discharging the battery once I got my new battery, but I find it very inconvenient. I also noticed that there's a "Disable Battery Charging" setting, so I was wondering if using this setting and leaving my computer plugged in would save my battery from any negative effects of having it fully charged and still plugged in.  I asked Dell's twitter account, but they directed me back to the FAQ that said this was unnecessary.  And this right after they posted the Alienware FAQ that said the opposite.  (My computer isn't an Alienware, but I believe it has the same kind of battery.)

I also had the idea of just taking the battery out completely and using the laptop on AC power only until I need to move it.  One of the Dell techs I talked to told me this would work, another told me it wouldn't work.

The internet contains arguments supporting and opposing every possible approach, including things like "maintain a battery charge of 70% at all times" or "take your battery completely out of your laptop for normal operations, but discharge and recharge it once a month." All of these arguments can be found from credible sources and backed up by scientific explanations.  I could write a paper with quality citations in support of any possible approach to battery management.

And I still haven't the slightest idea which approach is actually correct.

My intention when writing this blog post was to put the question out to my readership, but that will just be more sensible people giving soundly-reasoned explanations on the internet.  I seriously don't know what to do.

Opinions are welcome, even though I'm tired of opinions.  I'm particularly interested in:

- What is your own battery management approach, and what kind of battery lifespan do you get?  (By "battery lifespan" I don't mean "how long until your battery drains and you have to recharge it?", I mean "how long until you have to buy a new battery?")

- Would using the "disable battery charging" function while leaving the battery in the computer and the AC adapter plugged in eliminate whatever harm might potentially be caused by leaving the AC adapter plugged in when the battery is fully charged?

- Any experience with just taking the battery out?

Update:  I have since learned that the "disable battery charging" function gets better battery lifespan.


laura k said...

Ages ago, when I bought my first laptop, I had problems with the battery, and I was told exactly what you were - allow it to fully drain before recharging it.

Then as years went by, it seemed like no one paid any attention to that. An IT person told me the newer batteries and newer laptops no longer needed that approach.

My non-desktop computer is now a netbook. When I first got it, the battery would last for about six hours, which I thought was great. After about two years of pretty heavy use, the battery only lasted about 2 hours. I bought a new battery and it's back to around six hours.

I use it on battery until it is almost run down, then plug it in. However, if I'm using it where there's a convenient plug, I'll just plug it in to juice it up a little bit.

I never researched this. I use it this because it's convenient.

I hope this is helpful, but it sounds like it won't be. As you said, opinions abound.

impudent strumpet said...

I only get four hours out of my brand-new battery, but I usually have Sims running in the background (it runs from a DVD, which apparently takes up more power). But it took me 2 years and 3 months to need to replace the battery despite being plugged in all the time. Which makes me wonder if there's really that much difference.

laura k said...

Netbooks are very low use - no CD/DVD player at all, and I often turn the wireless off to conserve battery (sorry I didn't mention that earlier, just thought of it now). Considering the difference in use, your battery life seems normal to me, FWIW.

You could make your life easier by buying a new battery (assuming your laptop is in good shape and you want to continue using it) then use the battery however you want. That's what I would do, but I think I have less patience for proper research than you.

impudent strumpet said...

I did buy a new battery, I just don't much fancy the idea of spending over $100 every two years just because a component I rarely make use of wears out.

laura k said...

Oh wow, I had no idea it was so expensive. I wouldn't like that either.

My replacement battery was only $30, and I use it a lot - a different equation.