Laptop battery message [Archive] - Glock Talk

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GIockGuy24
08-03-2011, 18:54
I have a 4 year old Dell laptop that I bought new in the Summer of 2007 and then hardly ever used it for a number of reasons. I has always worked fine and still works fine. In total it less than a month's use on it. I usually use Linux on it but it also has a Windows partition that rarely gets used. I decided to get it out and update Windows. When I turn it on now I get a message on the screen in Windows that the battery can still be charged but is nearing its useful life and should be replaced soon. Is this message time triggered and related or does it really sense a worn down battery, maybe by the amount of current it draws to charge? I'm think it almost has to be it's age but would the system know if the battery was replaced?

This was a top of the line model when I bought it. Much of the hardware was so new that it wasn't well supported by Linux in 2007. I had the choice of Windows XP and Windows Vista and thought since I'm not going use Windows much I'd like to see how Vista works. Well the few Windows programs that I was interested in using wouldn't work with Vista. I put the laptop away and continued to use my old computers until bout a year and half later when I bought a netbook. It has worked so well I never got the laptop out to use. This past Xmas I bought myself a new laptop. Not an expensive one but one I knew was well supported by Linux. It's as fast or faster than the high end model I bought in 2007. It feels flimsy but it works and it's fast!

The 2007 laptop is now completely supported by Linux so it has no problems but I'm not sure how to take the battery message in Windows. The battery does fully charge.

MrSmoofy
08-03-2011, 19:24
Would be helpful know the make/model.

I have an HP laptop, it knows the life of the battery. My battery also has a button and light indication of it's health.

http://i51.tinypic.com/1z32bsm.png

HP Battery Check tells me the health of my batteries.

Linux3
08-03-2011, 19:29
Lithium-Ion batteries go bad just sitting on a shelf.
Something you have to look at when you buy a new battery. Don't trust that it has never been used! When was it made makes a difference.

GIockGuy24
08-03-2011, 19:45
I wasn't guessing that it stayed good because it wasn't used. I know they age even without use. I hardly use my laptops, so I'm not very familiar with the messages on them. I only get a message in Windows and it has been working fine. I think I saw some battery life app for Linux but I thought it was might only relate to the charged state of the battery and not the physical condition of the battery. For my netbook there are some off brand replacement batteries that people have said they have a difficult time to get some of those to fully charge although they charge enough to use for a while.

The notebook was one of the first Santa Rosa models available and it was one of the first to have the Nvidia 8xxxM series graphic and the first Intel Draft N wifi cards. When I ordered it was was advertised as having DDR3 graphics memory. Well Nvidia offered them with a choice of DDR2 or DDR3 to the computer makers. It came with DDR3 graphics memory. I was refunded $300 for that known issue. The laptop was offered with several different displays. Only one low resolution one was offered with antiglare. I wanted antiglare and not glossy. There were two companies providing the displays. The one that made mine made ones that look terrible.I was refunded $200 for that known problem. So after buying the laptop I got $500 back in refunds. I had to wait a while for Linux to support all of the hardware.

GIockGuy24
08-03-2011, 20:10
When I start the laptop in Windows I get the message about the battery nearing the end of it's useful life although it can still be charged. Then it says for more information click here. When I click it, it tells how to buy a replacement battery. The graphics card is pretty hard on the battery and it never held a charge long, even when it was new. I chose the smaller battery pack as the larger one stuck out from the laptop case and it was heavy. I almost bought a second one at the time but decided to wait and never did. If I had, it would be just as old as the one that's in it now. Later when I bought the netbook I did get the larger netbook battery pack,

JimmyN
08-04-2011, 05:13
It measures the voltage drop when you power up and while it's in use to determine battery condition. As a battery is cycled and ages it's ability to maintain voltage under load drops off and it's total mAh capacity decreases since the two values are related. You can use the voltage drop under load to determine a battery packs health.

Just to pick some numbers as an example, let's say it's a new battery pack in good condition and sitting at rest with no load (laptop off). The battery pack voltage is 14.8V. Now you turn on the laptop and the screen powers up, the drive starts turning and the CPU is drawing power. This current draw causes the battery voltage to slump a full volt down to 13.8V and for the mah capacity and "C" rating of the battery pack a 1 volt drop is expected at that current draw, battery status is OK.

Fast forward in time and the battery has lost some capacity with continued use and age. Now when you power it up the battery can't maintain the same voltage at that current draw so it's now dropping 2 volts instead of one. It will still charge to the same peak voltage level, but it can no longer maintain voltage as well under load, and thus the total usable mAh capacity has decreased. So battery status reports that the battery will soon need to be replaced.

It's actually a bit more complicated than that because voltage drop will vary depending on state of charge and current draw so that has to be factored against voltage drop, but the concept is the same.

MrSmoofy, it's interesting that your primary and secondary batteries are different voltages. The primary is a 3 cell Li-Ion (4.1V cell voltage) with a nominal voltage of 10.8V (12.6V full charge, 9V fully discharged) but your secondary battery is a 4 cell Li-Ion with a nominal voltage of 14.8V.

Actually the numbers appear to be a bit off on the secondary battery. A Li-ion cell has a full charged voltage of 4.2V, a fully discharged voltage of 3.0V and a nominal voltage (mid charge) of 3.6V. So a 4 cell Li-Ion pack should have a nominal voltage of 14.4V, a terminal (full charge voltage) of 16.8V and a discharged voltage of 12V. The numbers appear correct on the primary battery, but seem a little bit off on the secondary battery.

GIockGuy24
08-04-2011, 08:27
Thanks. I guess I'll buy a new battery or two for ir. It's still a fast computer. The chipset is suppose handle 8 GB of memory. The original BIOS would only work with 4 GB of memory. The updated BIOS is suppose to handle 6 GB of memory. The Dell's and especially this model are really picky about what brand of memory is used. A 4 GB module is about $80 for it and it's DDR2. I bought 8 GB of DDR3 for my newer, cheaper Core i3 Gateway laptop for $65. The Core i3 is dual core but shows up with 2 additional virtual cores. The older Dell works well with 4GB but if I'm going to buy a newer battery for it I may add some more memory to it.

GIockGuy24
08-05-2011, 14:28
I did find this battery information program for Windows.

http://www.nirsoft.net/utils/battery_information_view.html