Solved Calibrate battery

[ish4d0w]

Hi


This is a HP 6720s notebook. I'm having problems with my battery.

The percentage indicator is not accurate.

It randomly hibernates below 40%. It's only supposed to do that when it's on 5%. It's supposed to give a "low battery" warning on 10% but it never does that.


Do I need to calibrate the battery? If so what's the best method to do that? Do I need to run it until it's completely empty?

 

[indianacarnie]

With most modern batteries you really don't need to "calibrate" them anymore. Having said that.... I do mine about once every six weeks or so, but only if I remember. My battery is over a year and a half old now and gets used on a regular basis. It still charges to 100% so I guess I'm doing something right

I run mine till it turns off by itself or gets to less than 10%, then charge it completely. Or did until recently I should say. I've been running it down to around 50% and then recharge it to full now. No ill effects yet to the "new" routine.

I have a free program that includes a battery monitor .... but I am not on my machine at this moment so cannot recommend/remember what it was/is. Thinking it was primarily a HDD type program. Having said that I have never used it for the battery.

One last thought, have you considered running an sfc/scannow to find and possibly repair any corrupted system files? This may or may not help this specific problem but cannot hurt and may be worth a try. We have many excellent tutorials here written by some very talented people. Just click the link :http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html

Hope this helps.

 

[derekimo]

Additionally, here's a little info on calibrating your battery,

HP Compaq 6720s Notebook PC*-* HP Notebook PCs - Testing and Calibrating the Battery (Windows 7) - c00821536 - HP Business Support Center

 

[ish4d0w]

Thanks to both of you!
I'll try the SFC trick soon.


I'm not sure what should I do with this battery (other than replacing it)


Here's a screenshot of HP Battery Check. I was unable to switch it to English but I provided an English translation via captions.
There's only one string I'm not sure about, I marked that one with a blue arrow.

The red arrow shows an interesting data: Cell 1's voltage is 0 mV, why is that?


BTW. The computer was mostly on charger while this battery was in. That might explain it. Is it safe to continue use this battery? It still provides some power.

I have a battery in a better condition BUT I'd like to use this one too, as a backup when the first one runs out and I need more battery time

 

[PeaB4YouGo]

I've had to run a battery down to zero and wait for the sys to shut itself down. Then I try to power up several times, to the point where it won't even TRY to boot. Then, without using the computer at all, charge the battery to full. Of course, this was years ago, as I no longer support laptops, and battery tech has progressed, I'm sure. This may still work as a method of reinvigorating a battery and making the indicator a bit more accurate.

 

[momchi]

you have a bad (dead) cell

Modern LiOn batteries (laptops and phones) are built out of cells that are switched sequentially as the battery is discharged. The switching is done by a "smart chip" inside. It is the same chip who provides diagnostic info to the software testing layer.

If you see a cell with 0V (when you have fully charged your battery), this cell is dead and is (normally) not recoverable. That is why your machine "suddenly turns off/hibernates" when it reaches it and tries to switch to it for workload.

This (normally) cannot be fixed with any tool/calibration method and is only "fixed" by battery replacement.

*NOTE: Smart phone batteries have more than 50 such cells and for these, if your phone is rooted, there are a few apps that will let you "test and mark bad cells" - which a kind of works for a while, but more and more cells go bad every week or so, and this is really *not a solution*...

Hope this info helps you to avoid frustration - trying to understand/troubleshoot your battery issue

 

[ish4d0w]

Hi

Thank you very much everyone. I learned a LOT about batteries, so your answers were very useful for me.
I just replaced the battery and now it works fine.