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I own a Lenovo Y500 series laptop. The battery being an year old lasts only 1 hour. But the strange thing is that, when the charge comes down to 25-20 it drops to 6%(critical battery level) in a moment.

Please suggest some solution (other than replacing the battery).

P.S. : I do many battery saving things already, like lowering brightness, switching to power-saver mode, turning off 'aero' on windows, etc.

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Here is a similar question. Might provide more insight. –  SgtOJ Nov 28 '10 at 20:49

5 Answers 5

up vote 5 down vote accepted

Sorry to say it, but I don't think there's another answer to be had; what you are experiencing is usual for a battery that needs replacing.

Their expected life-span is only about 1 year (according to the manufacturers).

The reason the readings act weird is because when the battery becomes old and faulty it can't properly gauge the total capacity or current charge, so the gauge readings are based on inaccurate numbers.

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I've seen this exact behavior with my Dell Latitude - the original battery would go find until it hit about 45%, then die in about 60 seconds. Basically it means your battery is shot and you need a new one. –  Michael Kohne Jun 22 '10 at 15:48
I've had multiple batteries die this way. I believe it is an indication that one of your battery cells is actually dead. –  SysAdmin1138 Jun 22 '10 at 16:12
Thanx guys :) I better get a new battery. –  Karan Jun 23 '10 at 13:18
@Ƭᴇcʜιᴇ007 , expected life is 1 year? Isn't it 3? –  Pacerier Jan 19 at 3:15

There is some problem with the Lenovo Battery/UEFI Firmware. The Battery Manager on Window or tp_sampi module under linux is usually configured to extend the batteries life by only charging it to 85%.

But discharging the battery from 85% (eventually somehow related to hibernate) can cause the batteries charge counter to drift off more and more over time. The result is a sudden drop of battery life at some point (in my case, at around 45% it suddenly drops tp 6%). The battery reports 85% way too early.

People reported that setting the thresholds to 100% mostly resolved the problem after a few full charge cycles.

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That is an interesting answer: I too have a Lenovo laptop. And I noticed it after I choose to charge the battery only up to 85 percent in-order to extend the battery life. –  Fermé somme Apr 13 '14 at 11:14

I had same issue as yours. I posted question saying that notification is not showing up in Windows7. After posting the question here, I did try to find the problem and I found that even my battery life jumps same as yours from 25%-6%. After looking at your question, even I thought my laptop battery life is over. But, somehow I wanted to retest it again by changing some settings in the Balanced power mode and surprisingly it started working fine after changing couple of settings. If you look at my question Brian suggested some finding on net about this issue, so I tried to modify settings to get the notification after that it never jumped from 25%-6% again. Now, my laptop is working fine and notifying me when it reaches 10% and hibernates when it is at 5%.

As the answers you got from techie007 and others I'm not sure whether they should be accepted as is. I'm saying this because as soon as I shifted from XP to Windows 7 this problem started. I was bit lazy in finding the problem so I let it go for a month or so without investigating. But yesterday when put up a question all these findings have come out. Since then I was continuously testing my battery with full charge to completely dry out, it never jumped again. I'm not sure about your case, but in my case above answers doesn't apply to me and it might be a bug in the Windows7 OS. May be to get more clarity I need to switch back to XP, but I cant to do that at this moment.

One more addition to this reasoning is I've got 3 same laptops bought at the same time and all are having XP on them, they are still working fine only my laptop got this issue by switching to Windows 7.

May be I can check this by switching other laptop to Windows 7 in couple of weeks. I'll update it after that. Hope it works well.

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Thanks Jay, I'll try it out. –  Karan Nov 30 '10 at 18:54
@karan: I tried with other laptop as well and I found that its a problem with Windows7. So, I'm sure even your problem should be solved. –  JayaprakashReddy Dec 7 '10 at 6:06

I know this is an old issue, but I've had the problem myself and the solution was to charge it fully, then leave it plugged in at 100% for about 2-3 days. After that, it discharged normally without any sudden % drops.

The issue I was having with Arch linux using TLP's battery re-calibration: the battery percentage would suddenly drop from around 60% down to 6% during the re-calibration itself. I didn't try discharging it normally, previously. The problem occurred after an extended period of leaving the laptop plugged in at around 50% capacity.

I've reset the charge thresholds on my Thinkpad now, and I'm going to observe how it works. If the problem re-appears, I can simply re-calibrate it the same way again.

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You could check your computer's documentation to see if it mentions anywhere battery calibration.

How often did you let the battery drain all the way? Since you said it's 1 year old, there is a good chance that it's lithium-ion battery, and you shouldn't let them go below 20% charge because if you do, they will wear out much faster than they normally do.

Just as techie007 said, the battery need to be replaced

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