jump to navigation

Getting Details about My Laptop Battery – and Taking Care of it April 8, 2007

Posted by Carthik in guides, maintenance, ubuntu.
trackback

Recently I have noticed that the “stamina” of my Acer notebook’s battery has been getting progressively worse. The laptop is hardly a year old and yet I get only 3/4ths of the time I used to get with it when I bought it. I wanted to know more details about how my battery’s doing.

Laptop Battery
(img credit: Sean Dreilinger on Flickr)

To find out all the details you would want to know about you battery, browse to the directory
/proc/acpi/battery/ and then to the directory that has your battery in it.

Once there, see the contents of the files to learn more about your battery. Here’s what my files tell me:
battery statistics screenshot

So, as you can see, my battery does not charge to its full design capacity of 4400 mAh. It only charges to 3134 mAh, which is almost 3/4ths of the original capacity. Looks like my battery is on the downhill slide.

Since it is a Lithium Ion battery, I went looking for details on how to take good care of it. It is a good thing I did, because it demystified me – Letting your battery drain to “dead” before recharging it is not good. I really thought it was, but it is not. Wish I had known this earlier! I found an excellent page online with details of what factors affect the performance and lifespan on Lithium Ion batteries. The page includes graphs to show stored charge levels, temperature, discharge load etc affect battery longevity. In case you don’t have the time to read the page, here’s some points for you to remember to ensure a long life for your LiON battery:

  • Avoid frequent discharges to 0% stored charge.
    • Several partial discharges with frequent recharges is better, since Lithium-Ion batteries have no “memory”
    • You still have to allow it to go from full charge to near-empty charge once in 30 charge cycles to make sure that the battery charge monitor is properly calibrated
  • Avoid Heat
    • Don’t leave the laptop in the car
    • If you are going to use the laptop connected to power for a week or more continuously, take the battery out. This will save it from the heat and from the charge-discharge problems
  • The batteries deteriorate even when they are stored cool!
    • Don’t buy a replacement battery or a spare battery until the time when you really need it!
    • If you have to store a Lithium Ion battery – store it at 40% charge and store it in a refrigerator

Take care of your battery, because there is no way to restore capacity to failed batteries. Also, an average battery is good for 300-500 charge/discharge cycles, or about 1-2 years. The main physical reason for the degradation of performance seems to be increased internal resistance, which causes the battery to be unable to deliver the charge stored in it to the outside world (the internal resistance eats it up :) ). Chemical decomposition of components also reduces the charge delivery capacity over time. So it is best to do the most you can to slow down the degradation by following the tips above.

Comments»

1. Movi - April 8, 2007

>Take care of your battery, because there is no way to restore capacity to failed batteries.

That is _totally_ untrue. In my city there are multitude of places where you can get your Li-Ion or Li-Polimer (or just about any other laptop battery) “regenerated”. Unfortunately I am not a chemist, so i don’t know how the process works, but i did use this service to regenerate the battery in my old iBook G4, and it worked perfectly, and i payed 1/3 of a new battery (and i had o regenerate 3 out of 4 ‘cells’ or however you call the spaces that batteries are separated into). So if you really miss your lost capacity, get your battery regenerated.

Edward - October 21, 2009

No, you don’t get your battery ‘regenerated’. That makes absolutely no sense. If you have ever studied chemistry, you know that according to the La Chatlier’s principle, since more and more of the reactants in the Li-Ion are permanently on the product side over time (no chemical processes are 100% efficient), the equilibrium of the chemical system of the battery will shift more and more to the right side. This is why your battery loses charge over time. Once enough reactants disappear, for all practical intents and purposes, the battery is finished, period. If you want to reverse the effects, you would need to put more power into the system than it can handle and the battery pack would probably explode. Basically, what they did to your battery was that there are batteries (like AA or AAA, etc.) in the battery pack and just replaced them. That’s it!

2. carthik - April 8, 2007

If the battery is gone, its gone:

There are no remedies to restore lithium-ion once worn out. A momentary improvement in performance is noticeable when heating up the battery. This lowers the internal resistance momentarily but the condition reverts back to its former state when the temperature drops. Cold temperature will increase the internal resistance.

– From the guide

However the article does mention that in case of a low voltage, the battery can be fixed.

In any case, I understand irreversible physical and chemical degeneration are facts of life. Even if it were possible to reverse some of the ill effects, it would be expensive and difficult to do. So for all practical purposes, any damage to my batteries is permanent.

So, no, what I said is not “totally” untrue. I would love to learn about any service that guarantees restoration of any Lithium-ion battery, with the price for such service. :)

3. Shane - April 8, 2007

My battery applet gets stuck sometimes and never shows the correct time remaining or even the state (charging or discharging). Is this a common issue? I’m using Edgy when I experience the problem.

4. skunkyjay - April 8, 2007

You know… I had to spend a lot of time sifting threw what was good information about saving your batt. I think it would be nice to have some information that could be easily accessible from gnome powermanager. I wonder if they could say anything in the program without interfering with it’s perfect simplicity. Thanks for the info…

5. Casey O'Donnell - April 8, 2007

you think you got it bad?
design capacity: 5200 mAh
last full capacity: 2415 mAh

BeRniTo - April 19, 2010

So you think you got it bad?

design capacity: 4400 mAh
last full capacity: 1653 mAh

Guess how old is it?? Just 6 months!! :-(

6. www.tipshack.com - April 8, 2007

How is your battery life, big boy?

Find out more information on your battery. Also some tips on how to keep it in tip top shape. I looked in the directory but my files were empty, maybe yours won’t be. Leave a comment and vote if you see anything.

7. Harlem - April 8, 2007

I looked in the folder but my files were empty? Should I be running on the battery instead of the wall outlet to see the information, even though the battery is in?

Nice little tip.

8. benni. - April 9, 2007

> Letting your battery drain to “dead” before recharging it is not good. I really thought it was, but it is not.
I always thought that too, and it tried it with my Sony Laptop which is now 2.5 years old — I almost always recharged it from around 1-2% and this is the result:
design capacity: 48840 mWh
last full capacity: 45960 mWh

I think it’s pretty good for a 2.5 years daily use of my laptop (and the first LION).

9. Tavis - April 9, 2007

I went to /proc/acpi, but there is no “battery” directory. Does that mean my laptop doesn’t support it, or is it someplace else?

10. Kari - April 9, 2007

I also wish the Gnome Powemanager would have an extra menu option to view this information. It could also track the power level and display is as a graph – so it would be easy to see when was the last time the battery went from full charge to near empty etc. That would help people to take care of their batteries. Now I have to try to memorize the last time..

My one year old MacBook gives me mWh’s instead of mAh’s (on Dapper):

design capacity: 50200 mWh
last full capacity: 46470 mWh
battery technology: rechargeable
design voltage: 10950 mV
design capacity warning: 250 mWh
design capacity low: 100 mWh
capacity granularity 1: 10 mWh
capacity granularity 2: 10 mWh
battery type: LION013

11. carthik - April 9, 2007

Kari,

That sounds like a wishlist bug – please file one if you think it essential.

12. carthik - April 9, 2007

For those missing the “battery” directory, maybe it is that the laptop has poor acpi features, or that the kernel module for battery management are not loaded.

13. Yuriy - April 9, 2007

Thanks for the info!

*gulp*
design capacity: 76500 mWh
last full capacity: 38220 mWh
Hmm… I thought it should be lasting longer! This laptop is only 6 months old. Warranty time?

14. Brent - April 9, 2007

I wonder if it is possible that an OS can cause the battery to not charge fully.

Install Windows on it and see if you still have this problem.

15. Huygens - April 10, 2007

Feisty, or actually Gnome 2.18 can display the mentioned information with the Power Manager applet.
So if you have Feisty (either installed or via the Live CD), you can just click (normal left click) on the battery icon in your panel and click on the first item of the menu which is called “Laptop battery (100%)” on my computer.
It gives me the capacity information and various other information.
As for the current state, you need to right click on the battery icon this time. There in the “Power history” item you will get current and past information about the battery and acpi states :-)

16. charlie - April 11, 2007

Yeah, battery wear is normal to an extent. 75% battery capacity after a year’s pretty bad, unless you’re using it EXTENSIVELY, but quite possible. To Yuriy’s comment though – a 6 month old laptop definitely should not have 50% wear.

I have an ASUS Z71V and the battery wear level’s gone to insane levels twice now. After the first three months with the laptop, wear levels were around 50%, and even with the replacement wear level was ~60% after a year. Luckily it’s a known problem and ASUS replaced both batteries for me – I just got the 2nd replacement battery today. Hopefully this one’ll hold up a little better.

17. Mikem - April 14, 2007

Just like to say that my Fujitsu battery has lasted very well for these last 5 years. According to the ‘info’ it’s design capacity is 4016 mAh and last full capacity is 4011 mAh. Which are both, more or less, spot on the original 4000mAh mark.

18. Ice and Fire » Getting more from your battery - April 16, 2007

[...] you are a freak to get even more information, you can use the command line (thanks to carthik for this hint). Just open a terminal (Gnome “Applications” menu -> [...]

19. *Gian* - April 16, 2007

My battery had a weird story.
It works perfectly for 2years and half.Probably it lose 30′ over 3hours. But then in a couple of weeks it totally stops to work!!!
I don’t know if the change of supply power (the old one was broken) affect it but they are the same (at least on the label they have same input and output).

@Kary
I can see what you wish in my gnome right know!Under Gnome Control Center->Battery ( I haven’t my laptop with me right now).

PS
Nice blog

20. Sandy - April 17, 2007

You think you have it bad? ;)

I also thought that draining the battery fully, and leaving it there for a while to then do a full recharge would increase the capacity. (Yeah… i’m used to stoneage technology)
Instead i actually lowered my max charge from 42% to 39% by doing this…. sucks.
I thought lithium-ion batteries didn’t have these problems.
li-ion battery in my Palm works fine after over a year and still delivers near max charge.

But on my laptop…. info file says:
Design capacity:
6450 mAh
Last full capacity: 2560

All of the other stats are the same as yours except mine is produced by DYNA-SON.

This is on a HP laptop where they forced a 3Ghz Northwood stationary P4 in it. (Requires about 82W just for the proc)
Oh the joy… battery drains in less than an hour with freq scaled down to 375Mhz.

Good thing i mainly intend to use this lappy as a mobile “stationary” computer.
Still… would be nice with “some” mobility when needed ocasionaly, if this degeneration continues it will soon be wire bound.

New battery ~220$

Sure would be good if there was any way to recondition the battery.
Ripping it apart and replacing the “cells” usualy just isn’t cost effective even on older battery packs.
Guess i’ll just run this battery down entirely and then cough up for a new one.

Excellent info though!

21. Guillermo - April 20, 2007

My Acer Aspire 1642WLMi, 13 months old:

Manufacturer: SIMPLO (?)
Type: LION
Design capacity: 28,8 Wh (about 2 hours)
Last full capacity: 8,4 Wh (about 45 mins)
Capacity: 29% – Poor

22. Jo Forbes - April 21, 2007

My dad has an evesham cinebook laptop which he lets me use. He’s had it for two years and it’s had very light use. Over the last wee while though I’ve noticed that it always asks for the mains adapoter on starting. I plugged it in today and kept an eye on the battery charge meter and it has never got above 12%. Any ideas? Does this mean the battery is pooped??? A new one will cost about £90 and dad will no doubt go mental!!!

23. John - April 26, 2007

Good article.
I want to know how can i check the same on my windows machine?
Thanks.

24. FABblog » Blog Archive » Manutenzione della batteria del portatile - May 2, 2007

[...] Ubuntu Blog batteria, litio Pubblicato in Informatica, Tips & Tricks, [...]

25. kerm jensen - May 7, 2007

From multiple sources around the web . . . Lithium Ion batteries lose 20% of their stored capacity per year under optimal conditions. The batteries are not hard to recondition. There are only three components inside: a number of Lion cells or polymer packages, the wiring connecting the cells in series and parallel (usually) and the charge control circuitry. All you need is the thousands of dollars worth of appropriate equipment to cut open the batter, de-solder the cells, solder in the replacements (about $10.00 per cell), test (and replace if malfunctioning) the charge control circuits and then reseal the battery so the whole package will still fit in your laptop. Any remaining warranty on your laptop is, of course, void. As usual, the devil’s in the details and it’s more cost effective to simply buy a replacement battery.

26. cesar - May 17, 2007

Just a quick question:

You say several partial discharges with frequent recharges is better, since Lithium-Ion batteries have no “memory”, but the cycles would run out quicker too since you say an average battery is good for 300-500 charge/discharge cycles. Would this tow points be at odds since partial discharges with frequent recharges would mean cycles with shorter times?

Thanks for your kind response,

27. Nathan - May 26, 2007

Are after market replacement batteries just as effective as OEM Batteries? I assume that some replacement batteries are better than others. Any recommendations for an HP ZT3000?

28. AimZ » PowerTOP Intel - June 1, 2007

[...] Korner – Extending Battery Life with Laptop Mode | Linux … Getting Details about My Laptop Battery – and Taking Care of it … This entry was written by stefan and posted on 1. Juni 2007 at 07:38 and filed under Hardware, [...]

29. Mike - July 31, 2007

http://www.topmicrousa.com is a good place for replacement laptop batteries. From my experience, aftermarket batteries out perform OEM ones. Most companies also include a warranty. Avoid generic branded batteries because they wear out quickly.

30. Skinnybrown - August 17, 2007

For some reason my Ubuntu no longer detects the battery. It worked when I was running Edgy, but when I upgraded to Feisty, all the information in /proc/acpi/battery disappeared. The strange thing is that the live CD detects it correctly. Does anybody have any ideas on how to fix this?

31. Μπαταρίες Laptop « Azimout’s Weblog - August 23, 2007

[...] Για όλους τους κατόχους laptop, παραθέτω αυτές τις οδηγίες, που ομολογώ ότι ούτε κι εγώ είχα υπόψη [...]

32. Paul - August 29, 2007

my laptop says no battery found it is new and just got it home, does it have to be charged first and if so how….please help..

33. Len - October 15, 2007

Ok, here is a strange one is anyone would like to help me out. After much research on the net, I’m still in the dark on this one…

Problem: I’m using an ACER Aspire 3000 (nothing great, but it works for me on the road), I’ve had it about two years now. When the battery is plugged in, my system runs “extremely” slow. To type out a word even takes me several seconds as there is a huge delay in between each letter being registered by the system. If I remove the battery and run on power only, the system runs perfectly. I have no idea why this is happening. I can only assume the battery is bad, but why would a bad battery cause the system to respond this way?

ANY help on this would be greatly appreciated.

Thanks,

Len

34. Tony - October 31, 2007

How to go to the directory /proc/acpi/battery? Details please.

Thanks.

35. It’s HARDbutWARE » Getting Details about Your Laptop Battery - and Taking Care of it - November 13, 2007

[...] read more | digg story [...]

36. Roel - November 30, 2007

Len,

I just found out that my acer aspire 3000 has the exact same problem… it would slow down until even the login screen would freeze. The battery had been 3% for awhile and didn’t seem to get charged, so I’m suspecting I need a new battery. Hopefully there are better batteries out there. I just read an article that said Acer should have included a 6-cell battery, not a 4-cell. Maybe that’ll help you too. Let me know if you find out anything about it!

37. Tam - December 15, 2007

Hi, I have an old prodigy laptop with LI-IOn battery. It was working perfectly and all of a sudden it stopped working. The Adaptor light is green but the laptop refuses to come on. The battery is DC 14.8V 3000mAH. Please what do I do? Thanks

38. Tam - December 15, 2007

And if the problem is a new battery, is this what I need to buy?-DC 14.8V 3000mAH?

39. Granny - January 25, 2008

If your present battery has 10.8V and 4300 mAH, is it better to get one that has 10.8V and 6600 mAHl Also while looking for a new battery, most of them don’t list the battery life (how long I can operate my laptop without power)

40. Blog bookmarks 02/20/2008 « My Diigo bookmarks - February 20, 2008

[...] Blog bookmarks 02/20/2008 Getting Details about My Laptop Battery – and Taking Care of it « Ubuntu Blog [...]

41. NeedbatteryUS - April 8, 2008

NeedBattery.com is the ultimate source for batteries, adapters and accessories at rock bottom prices. You will always be able to find the top selling brands at discounted prices. Our top selling batteries are for laptops, digital cameras and cordless phones. At NeedBattery.com, we take pride in making your battery search easy.

Browse By Category
AA/AAA Rechargeables MiniDisc Walkman
Alkaline Monitor
Barcode Scanners Mp3 Players
Camcorders Palmtop
Cellular Phones PDA
Cordless Phones Portable DVD Player
Desktop Computers Power Tools
Digital Cameras Printer
Flashlight Two way radio
Laptops UPS Devices

42. LimeTiger - May 21, 2008

Len,

I have an Acer Aspire as well – same thing…

If I boot up with the battery in, my touchpad freezes – unresponsive, and the keyboard doesnt work either – I can t even type out a word. But take the battery out and hey presto, the machine works like a dream.
WHATS UP WITH THAT, ACER?

Also, my batter has always been TERRIBLE. If you leave the machine on and let the battery run down all by itself it would die in about 30mins…
WHATS UP WITH THAT, ACER?

I guess now its time to get a new battery to see if that resolves the problem – if not, Im sure the laptop will make a lovely bonfire.

Good luck !

43. Priyadarshan Hari - August 4, 2008

I have an HP pavilion dv6449us. It is hardly a year old. The capacity is down to half. The battery discharges by 10% every day even when it is switched off. Has this got something to do with BIOS settings?

$cat info
present: yes
design capacity: 6000 mAh
last full capacity: 3904 mAh
battery technology: rechargeable
design voltage: 14800 mV
design capacity warning: 202 mAh
design capacity low: 122 mAh
capacity granularity 1: 10 mAh
capacity granularity 2: 25 mAh
model number: Primary
serial number:
battery type: LION
OEM info: Hewlett-Packard

$cat state
present: yes
capacity state: ok
charging state: discharging
present rate: unknown
remaining capacity: 2592 mAh
present voltage: 11380 mV

As it is seen that the capacity has almost reduced by half within a year. Is it a problem with AMD processors.

44. gillbates - September 22, 2008

When my Toshiba battery went poof, I had it repacked at a laptop service shop. What the shop did was to open the battery case and replace the old cells with new ones. Before repacking, I could still charge to 100%, but it will only last for 10 minutes. After repacking, it will charge up to 99% but last for more than 2 hours (same performance as when it was new).

45. ahmad - October 27, 2008

I am a persian.I want to know that when I want to use my notebook with its charger,should I keep out the battery or keep in it?

46. Dave - November 29, 2008

Len, Roel, LimeTiger

Acer isn’t the only one to have this problem. I have an old Dell Inspiron 8100 and the original battery finally dried up completely (absolutely no lights on the integral status meter). As with you, the system was EXTREMELY slow. The grub countdown timer took 50 seconds to count down the five seconds to boot, and my plan to log in as root to check out some system issues were completely dashed when I found out how long it took just to type “root.”

It took me about three hours to stumble upon the problem (and googling was useless) but once I popped the battery out—presto! Works perfectly. (MemTest86 and fsck found no problems).

It must be something in the BIOS that tries to keep polling the battery state and gets garbage in return. In addition, when I tried to run MemTest86 with the battery still installed (I thought it might be a memory issue) the return values for the processor speed and L1 and L2 cache data rates were complete garbage (trust me, my PIII does *not* have a 24.3 GHz processor :-)

Just wanted to save Acer from being the target of un-necessary angst (well, for the battery issue, anyway :-)

-Dave

47. Kari - January 16, 2009

I wrote a comment about my battery on my one year old MacBook, on April 9, 2007. The results were pretty good: 46470 mWh / 50200 mWh = 92% of maximum.

Now, my battery is very weak, so I started to search for an answer – and here I am again!

The results for my almost three year old MacBook battery are not so great:

design capacity: 50200 mWh
last full capacity: 15940 mWh
battery technology: rechargeable
design voltage: 10950 mV
design capacity warning: 250 mWh
design capacity low: 100 mWh
capacity granularity 1: 10 mWh
capacity granularity 2: 10 mWh
battery type: LION013

Sadly, only 15940 / 50200 mWh, that’s 31% of max…

The nice thing is that right clicking the Gnome Power Manager now (8.10 Ubuntu Intrepid Ibex) gives power usage history and a nice graph. Great!! (but no design capacity/last full capacity values)

48. markus - April 27, 2009

would love to check out my batterfy perfromance but having difficulties finding out that info. can you explain in a little more detail how i come about the information re my battery life?

49. abdulhameed khan - May 29, 2009

Goodmorning I purchased Acer Laptop in april 2009 and uing it for the last 50 days 70 % with battery. now it seems it i fuly dischrged. I want to know how much hour it take to charged. one indicator ( blue.) anthr iw blinking anber .

50. sikiş - October 21, 2009

In my city there are multitude of places where you can get your Li-Ion or Li-Polimer (or just about any other laptop battery) “regenerated”.

51. ksjs - December 15, 2009

you say that a lithium battery shouldnt be totally discharged yet the manufacturer claims this can be good practice where battery degradation is apparent

http://support.packardbell.com/uk/item/index.php?i=instr_notebook_batterylife&psn=104274930138

whos right?

52. BeRniTo - April 19, 2010

So you think you got it bad??

design capacity: 4400 mAh
last full capacity: 1653 mAh

Guess how old is it?? Just 6 months!!! :-(

53. Tyler - May 11, 2010

Hi there, i have a windows 7 Toshiba nd i need to know how to cehck the last current charge etc? Thanks

yonian - August 2, 2010

Google “Windows 6 powercfg -energy”

yonian - August 2, 2010

oops – Windows “7”, of course. (Stupid netbook keyboard!)

54. Estefanos Fikadu - May 27, 2010

Really thanks for technology and also the one who wrote about acer laptop.I am Ethiopian and also I work in National Meteorological Agency but I took 6 months computer maintenance courses. I try to maintain soft ware and hard ware part of any computer every night in my house but you know Ethiopia`s education that much is not enough to do every thing so that please send me VCD ,text etc for more information I will send you my training paper.

55. FIDELIS P. - July 31, 2010

Hi, I use an HP laptop with a battery life of about 2 hours when fully charged. all of a sudden it just dropped to 20minutes even when fully charged to 100%. There has been no signal or sign of a drop before now. can somebody please explain what has happened to me. I have replaced my charger to now avail.

56. sikiş izle - September 26, 2010

ooh neat. thanks!

57. antalya ilaçlama - September 27, 2010

My battery applet gets stuck sometimes and never shows the correct time remaining or even the state (charging or discharging). Is this a common issue? I’m using Edgy when I experience the problem.

58. porno sikiş - September 27, 2010

For those missing the “battery” directory, maybe it is that the laptop has poor acpi features, or that the kernel module for battery management are not loaded.

59. sex sikiş - September 28, 2010

In any case, I understand irreversible physical and chemical degeneration are facts of life. Even if it were possible to reverse some of the ill effects, it would be expensive and difficult to do. So for all practical purposes, any damage to my batteries is permanent.

60. antalya böcek ilaçlama - August 8, 2011

antalya ev ilaçlama

61. ibs 2012 link - November 25, 2011

them laptop batteries are a real problem.

if you have trouble with ibs try the link below trying to work out cures for the deaded ibs irritable bowl syndrome.

ibs blog help click link

62. Www.Deepbeep.Com - August 15, 2014

obviously like your web site but the truth is should check out the spelling on a lot of the articles you write.. http://Www.Deepbeep.Com Quite a few will be rife having transliteration issues and I to find that quite problematic to inform the reality on the other hand We’ll certainly appear again once again.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 530 other followers

%d bloggers like this: