Thinkpads Forum

Before this happened, I could get 3 hours out of the battery. Typically I use the battery 3-4 times a week and would run it dead once a week.

Over my winter break I set up the thinkpad as a server and it ran 20 days on AC power with without discarging it.


Now I get 1:20 at most.

Would running it dead and charging it do anything for it?

No - and i don't think you hurt it - but heat and age can impact the battery life.

My guess is that it was in a very warm place for a while. Otherwise. one of the cells could have shorted out.

One other option is that it is fine - but that the power measurement thresholds have become wrong. This is what Lenovo resets when you do the "battery gauge reset" thing. In my expereince, I always get a lower number when I do this - the deep discharge cycle does more harm than good.

The bedroom is somewhat cold - usually around 60 degrees.

But I decided to see just how dead is dead. I went for at least 30 minutes with it saying 0 minutes left in a class. So apparently I just have to do a battery guage reset and see how it goes from there.

Deep discharge isn't good for lith-ion batteries?

Miller88 wrote:snip....Deep discharge isn't good for lith-ion batteries?

Yes, it's not.

just view the battery recall information

How old is it? It's definitely a "wear and tear" part. I use the ThinkVantage tool "Power Manager", but you can just configure your OS to not charge the battery if you use your Thinkpad on AC a lot.

Isn't keeping a LIon battery charged at 100% bad for it as well?

fparisi wrote:Isn't keeping a LIon battery charged at 100% bad for it as well?

It is said "You can't overcharge a LiIon battery", but it is still recommended you do some sort of battery maintenance.

http://batteryuniversity.com/ <--- lol...

Just don't charge unless you travel a lot, for one. I have it so it won't charge until it hits 85%, which from 100%, takes a LONG time when on AC. And I carry a 2nd 9-cell battery for travel.

So what is the bottom line here? If I use my T61p 99% of the time plugged in to the wall socket should I just remove the battery? Or am I hurting it by leaving it in?

The batteries in my old T30 were worthless after a few months of leaving them in while I was plugged into the wall socket.

I don't think you gain enough to make it worthwhile to remove the battery while running on AC because as I think has been said here in this thread already, you can configure the Power manager to not charge the battery until it reaches some desired level and to stop charging when it reaches some desired level. Also, on the old systems, they wouldn't run at full speed unless the battery was installed. Not sure if this still applies to the T6x series but still the installed battery operates as an uninteruptible power supply so it's good to leave in for that purpose alone. Since deep discharges are bad and cycles are bad, and like you, I use mine on AC 99% of the time, and they say 40% charge is ideal for storage . . . taking all that into consideration, I decided to leave my battery in and set it to start charging at 40% or below and stop charging at 50%. That's the bottom line for me. YMMV.

My T43 has a setting for Optimed Battery life. It is located in the Power Manager (battery icon). Battery information tab. Battery Maintanence dial log box.

I am not exactly sure what it does. Does anyone know its charging parameters?

Padhead wrote:My T43 has a setting for Optimed Battery life. It is located in the Power Manager (battery icon). Battery information tab. Battery Maintanence dial log box.

I am not exactly sure what it does. Does anyone know its charging parameters?

The software (if I understand it correctly) monitors your battery usage. If you you're on battery often - it maintains 100% charge when you're on AC. Ensuring you have a full battery when you need it. If you're rarely on the battery - it lowers the point at where it stops charging, so that it doesn't keep your battery at 100% for long periods of time, extending the service life of a battery that would normally be much shorter.

Some people I work with used to take the batteries out of the laptops to "save" them from overcharging. One quick power-outage in the office changed their minds about that.

I'm wondering about battery life and the charger in Tpads now. Following the advice above, I set the charging parameters from the default to optimize the battery's long-term life, since I also usually operate on AC.

But on my last laptop (a Compaq actually designed by DEC) there was no problem getting 3-4 years or more on a battery, even though the machine was on AC most of the time. Proving only, I guess, that charging parameters will be a mystery to most of us most of the time.

Even with the Lenovo charging scheme set for best battery longevity...would I be better off then removing the battery during those days when it is simply going to be on AC? Is there any definitive guide from Lenovo, or Saft, or anyone in the business with more than just opinion to go on?