How to Maximize the laptop battery ?

[krypto_wizard]

I have heard various stories for maximizing the laptop battery.

What you people do. Do you regularly drain it or do you alway plug it in to some power source.

Lets share some experiences. I lately bought a new laptop and Ubuntu is right there as the only OS.

[dca]

When I'm at the office with my laptop (two years old) I'm plugged in. Once a week maybe I use it at the house, I run on battery. Over time, now my battery only lasts a little over an hour. (1h, 17min), as opposed to 3+ hours when it was brand new...

[x64Jimbo]

regularly draining the battery is no longer necessary with the Lithium family of batteries. They do have limited charge-discharge cycles, and draining them on purpose only adds one to your count of charges and discharges.
I dim my LCD as far as possible when lighting conditions permit - it saves a lot of juice. Also, turn off unused network interfaces and daemons.

[prizrak]

Maximizing overall battery life is hardly possible. Batteries are designed to work for about a year, sometimes you can get a bit more sometimes a bit less.

As far as using one, basically turn off everything you don't need. If you have an nvidia based card, install Windows as Linux driver doesn't support GPU throttling. (I know it's a sucky advice but sadly it is the reality of it)


They do have limited charge-discharge cycles, and draining them on purpose only adds one to your count of charges and discharges.
Well there is a flipside to it. If you keep your laptop plugged in 24/7 might as well take the battery out and never use it. Most people who use laptops however will unplug it when going somewhere while it's still running and plug it in before the battery drains. That's basically wasting the charge/discharge cycles so might as well let it drain all the way if you are going to unplug it.

[Kannisto]

Maximizing overall battery life is hardly possible. Batteries are designed to work for about a year, sometimes you can get a bit more sometimes a bit less.

As far as using one, basically turn off everything you don't need. If you have an nvidia based card, install Windows as Linux driver doesn't support GPU throttling. (I know it's a sucky advice but sadly it is the reality of it)


Well there is a flipside to it. If you keep your laptop plugged in 24/7 might as well take the battery out and never use it. Most people who use laptops however will unplug it when going somewhere while it's still running and plug it in before the battery drains. That's basically wasting the charge/discharge cycles so might as well let it drain all the way if you are going to unplug it.Best thing to do for your battery is to keep it at 50 % charge when it isn't used (keeping it in refridgerator also slows its aging). Keeping it completely without charge is a very quick way to render it useless. Recharge cycles are counted as whole so discharging it only a little doesn't shorten its life as much as whole discharge and charge. Lithium-ion batteries die also from old age 2-3 years is their expected lifetime even when they are not used at all. Generally they last about 500 whole discharge/charge cycles which is in active use about 1,5 years.

[ubuntu_demon]

I'm new to laptops. But I'm finally getting one soon. When I get it I will provide more information about it :).

My plan :

* about twice a month I'm spending a weekend at my old home. This is a long train ride so I'm draining the battery twice.

* At home I'm going to plug it in unless it's below 50% (when it's below 50% I'm going to drain it first).
QUESTION : in this plan is it better to do it this way (with the battery still in) or to drain the battery first ?

* When at the university (I'm still a student) I want to be mobile. I will run it on the battery until it drains and then plug it in if necessary.

* I think this will mean that I will drain the battery once about every day on average.

* I'm not going to buy an extra battery or swap it in and out of the laptop constantly. I hope to able to use it as long as possible.

* I'm willing to buy a new battery after 1-1.5 year if necessary.

What do you think about this plan ? Any feedback/tips ?

added QUESTION

[GStubbs43]

I've read that you shouldn't drain the battery as it is aactually bad for it since it has a limited charge cycle. But, if you are going to have it pugged in a lot, let it drain to about 40% then take it out and use it plugged in with no battery.

[ubuntu_demon]

* At home I'm going to plug it in unless it's below 50% (when it's below 50% I'm going to drain it first).

QUESTION : in this plan is it better to do it this way (with the battery still in) or to drain the battery first ?

[Kateikyoushi]

I undervolted my cpu, while on battery I dim the lcd, and turn off the hdd and run the cpu at 600Mhz.
Never really cared what might be the best for the battery used it as it was the most comfortable.
I am going to buy one or two new batteries, this time I will be more careful about them, I am curious if it makes a significant difference.

[GStubbs43]

* At home I'm going to plug it in unless it's below 50% (when it's below 50% I'm going to drain it first).

QUESTION : in this plan is it better to do it this way (with the battery still in) or to drain the battery first ?

...You shouldn' drain it all the way, but ou should leave the battery out at about 40% if you're just going to have it plugged in.

[jcrnan]

Hmm.. I dont know, I have had a hp widscreen laptop and ive used it with and without power a lot the last 9 months or so and the total battery time has gone down with about 40 minutes. At first I could use it for about 3 hours and standby was about 3 and half hours. Now its at 2 hours and 20 minutes if I use it and a standby of a bout 2 and a half hours. I think thats pretty good for a pc that has been used almost 24/7 and prolly plugged in and out an average of at least once per day and also completely discharged sometimes as well.

I havent really done anything to keep the batter alive tough, and with the current battery time it doesnt seem like I will have to buy a new battery in at least another 9 months =)

[ubuntu_demon]

...You shouldn' drain it all the way, but ou should leave the battery out at about 40% if you're just going to have it plugged in.
But I'm not going to remove the battery when I plug my laptop in. Do you take that into account in your advice ?

[Kannisto]

But I'm not going to remove the battery when I plug my laptop in. Do you take that into account in your advice ?

Apple has published very good documents about this, take a look http://www.apple.com/batteries/notebooks.html

[ubuntu_demon]

After reading the manual of my new laptop and a bit of thought I decided to plug in my laptop as much as possible. Sometimes I run it on battery for a while at school or in trainrides. This seems like the easiest approach.

Since I use this laptop often I'm not going to bother with removing my battery.

I'm prepared to buy a new battery after 1-2 years if necessary.

[tagra123]

I made a backup battery pack that provides 19.2 volts using two radio shack 8 AA Cell battery packs and 16 energizer rechargables. I found an adapter cord and plug it into the same place the line power adaper plugs in. This can double the laptops battery time, or you can use the adapter by itself. By the way I put an inline fuse in the homemade battery pack to prevent accidents. It was less than $40.00 for all the parts, including the batteries, and I can easily get 2 hours with the homemade pack and around 3.5 hours when both are connected. The batteries I used were 2500mah.

[esaym]

Lots of info http://www.batteryuniversity.com/parttwo-34.htm


# Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.

# Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.

# Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.

# Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)

# Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.

# If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the battery at 40% state-of-charge.

[Audimage]

I undervolted my cpu, while on battery I dim the lcd, and turn off the hdd and run the cpu at 600Mhz.
Never really cared what might be the best for the battery used it as it was the most comfortable.
I am going to buy one or two new batteries, this time I will be more careful about them, I am curious if it makes a significant difference.


Would you explain how to do all of those things for us noobs? Thanks

[jdong]

To get the most runtime from your charge:

* Dim LCD panel as much as comfortable for your eyes, also turn off the LCD panel when not in use
* if you aren't using your network adapters, bring them down (ifconfig <interface> down)... it actually does save a bit of juice.


Otherwise, Ubuntu is preconfigured on laptops to be as battery conserving as is practical. Don't bother with setting your hard drive to shut off, because it doesnt' really save much power (and could actually expend more power and shorten the disk's life span).

As far as prolonging the lifetime of your battery, on modern lithium batteries, try to avoid fully discharging the battery if possible, and use the battery once every few times... don't leave your laptop always plugged in like a desktop -- discharge the batery a bit every few days.

[Audimage]

I made a backup battery pack that provides 19.2 volts using two radio shack 8 AA Cell battery packs and 16 energizer rechargables. I found an adapter cord and plug it into the same place the line power adaper plugs in. This can double the laptops battery time, or you can use the adapter by itself. By the way I put an inline fuse in the homemade battery pack to prevent accidents. It was less than $40.00 for all the parts, including the batteries, and I can easily get 2 hours with the homemade pack and around 3.5 hours when both are connected. The batteries I used were 2500mah.

Where would one find a HOWTO on this?

[PatrickMay16]

As far as using one, basically turn off everything you don't need. If you have an nvidia based card, install Windows as Linux driver doesn't support GPU throttling. (I know it's a sucky advice but sadly it is the reality of it)

Just making sure, does it not support throttling at all, or not support throttling for when the GPU doesn't need to be at its full speed? Just trying to get a handle on this, because it would seem that the linux driver does support throttling:
http://img20.imageshack.us/img20/4286/throttledz9.png

[Ubunted]

Just like to point out that some laptop models (older Thinkpads) won't work at all without a battery installed, plugged in or not.

[jdong]

Just making sure, does it not support throttling at all, or not support throttling for when the GPU doesn't need to be at its full speed? Just trying to get a handle on this, because it would seem that the linux driver does support throttling:
http://img20.imageshack.us/img20/4286/throttledz9.png

NVidia cards do not support dynamic throttling the way their Windows drivers do (PowerMizer, I think it's called?). Your video card runs only at one speed -- by default full speed, or you can (I THINK) underclock your card with nvclock to make it run below full speed...

ATI's cards do support throttling though (aka PowerPlay). With the open-source driver it's done via the Option DynamicClocks settings in xorg.conf, and with fglrx it's done via aticonfig. My Mobility Radeon x1400 reports:



jdong@jdong-laptop:~$ aticonfig --lsp
core/mem [flags]
-----------------
1: 135/135 MHz [low voltage]
2: 392/252 MHz
* 3: 446/342 MHz [default state]


The difference in battery life between mode 1 and 3 is nearly 45 minutes :)