Some questions about my Dell Latitude E6400 battery with Windows 7

I bought a Dell Latitude E6400 since 3/2009 from Malaysia with the specifications: Intel Core 2 Duo P8600, 4gb RAM, 160gb@7200rpm, 6 cells Sony - Dell battery, Windows Vista Business OEM

After a few months, I installed Windows 7 Ultimate on my laptops and after 3 months, the battery weared 85% with a "red X" at the battery icon, and a notification "Consider replace your battery". My notebook's battery lifetime is about 15 minutes.

I've searched for the error, and heard that this battery error caused by Windows 7 for old laptops. The system with Windows XP or Vista don't have battery damaged like this.

I just bought a new 9 cell battery ( Panasonic - Dell ) and consider to reinstall a Windows 7 Professional OEM for Dell now but i have some questions:

Is there anyone here use the Dell E6400 6500 or E5500, E5400 system upgraded from XP or Vista to Windows 7? Was the battery ok or damaged when running Windows 7? And if the battery was ok, which Windows 7 version are you using? Don't told me that I must return to XP or Vista, because my business needs the Windows 7.

Plz confirm me, many thanks

 

I was running Windows 7 Professional for about 10 months on my E6400 (until I replaced it) without any battery problems. It may be that your battery has lost its capacity. Some batteries die at little over a year (some die even sooner and get replaced under warranty). However, before declaring the battery as dead I would do a deep discharge. Run the computer on battery until Windows shuts it down and then start up, go to the BIOS screen and leave the computer running until it goes off. Then fully recharge the battery. This enables the battery electronics to recalibrate the battery capacity because it gets a new fix on 0.

John

 

Thanks much, John.

So how do you use your battery? Can you give me some advices about using, recalibrating, discharging, etc... plz

 

I think he did. Fully discharge your old battery as he described, and then re-charge it. Then just use it. If it is still worn out, replace it.

Everybody uses Win7 on laptops with batteries.

GK

 

I did it like he described long time ago, and the wear level is still 85%, the computer still shutdown after 15 or 20mins.

I just bought a new battery, so I want to know how to use it best: how often do I recalibrate it? Should I plug in the AC line and charge the battery when the laptop still in use? Should I charge it to 100% or ~96 - 97%?...

Thank you, pros

 

I do a full discharge every few months. Otherwise I let the computer top up the battery whenever it wants to. I do not recommend frequent full discharges of lithium batteries and most of the time my battery acts as a UPS. I would also not recommend the express charge option (I can't remember if the E6400 has this). Faster charging = more heat which doesn't help the battery longevity.

John

 

So then, your battery IS worn and/or failing. And you found this to be so within 12 months of buying your laptop. I would have contacted Dell then for a new battery under one year warranty.

Check the BIOS to disable any fast charge battery setting.

Use your new battery freely and hope to get a solid year or more of service out of it.

Win7 is suppose to be more processor efficient than Vista... less junk running. And I have not heard that Win7 is hard on batteries... this really would not be an advantage to Microsoft, Dell, nor the user.

GK

 

Thank you, John and GK

You can find out the battery problems with Windows 7 in this topic:

Windows 7 and the battery error "consider replacing your battery" (Part 1)

Many complaints here

 

Yes, but Microsoft continues to recommend a "new" battery. Maybe there are a whole lot of defective batteries out there, built to some old standard or something. I don't know. Feel free to install an older OS!

GK

 

When your wear level of you battery is higher than 60% Windows 7 will show this error message. Actually "60%" specs is what the laptop battery defines.
In reality, Dell set it to 60% to have Dell Control Point report you that your laptop battery is soon time to change, but Windows 7 takes it as the limit and that you have a really short battery life.

This feature is new to Windows 7. It has nothing to do with laptop compatibility.

I have to admit that 60% wear on a 9-cell is kinda stupid, as it still provides a over 5 hours of battery life (well on my system), but probably Dell uses the same circuit board on the battery for the 4, 6, and 9-cell, so they are all 60% wear level.

Dell, like all other OEM, doesn't consider this as a battery mal-function.