T61 9cell battery capacity - down 13% : how to fix this?

Hello folks:

My one-year-old T61 played a funny prank on me Until about 2 months ago, the battery was running at happy 97 to 100% capacity. Then, right out of the blue one day it dropped down to 94, then a week later to 91, then 89, 88, 87... Within approx 2 months I saw it go down 13%...

I am frenquent visitor here and have read the manuals on batteries, I follow the basics on charge/discharge, and in the past year I have not changed any of my usual "behavior" in terms of laptop usage and/or battery handling.

I have already tried twice to reset the battery though Battery Maintenance - to no avail. I use the factory provided 65W charger. Does any of you guys have idea how to recover at least some of original capacity back? Surely, I cannot ask for 100% after a year but the closer, the better

Cheers

 

If you have 88% of design capacity after a year you are doing very well.

I went through 3 batteries over the 5 years I had my T40, and the best I ever did was 80% of design capacity after a year.

I am not sure why it fell off so quickly in the last two months, but as long as it is still over 80% you have nothing to worry about.

If you haven't already you should set charge thresholds. This will help minimize cycles and keep up your maximum capacity for a longer period of time. However, no matter what you do it will degrade over time.

 

I'm about to get an x200 with a 9 cell. Any recommendations on how to set my threshold?

 

Lenovo power manager. Switch to advanced tab and click on battery maintenace and set a custom threshold.

The exact threshold you pick depends on how many hours you need to have on a moment's notice. If I can get 4 hours+ at reasonable settings I am satisfied. This generally works out between 50 and 60% of a charge on a 9 cell x200 or 8 cell x200 Tablet. This should be your baseline start threshold.

I recommend you choose 90-95% as the stop threshold as well. The last 5% of a Li-Ion battery is a very slow trickle charge. Also, Li-Ions don't like to be stored at a 100% full charge, so I only top it off all the way before an airplane trip or about every 20-30 cycles for calibration purposes.

Conversely, if you use your laptop at your desk most of the time (unlikely because you bought a 9 cell x200) you should try and keep your battery near 40% as this is the best charge level for room temperature or higher storage. I find a 30% start and 50% stop to be most effective in this case.

 

I like the idea re: battery thresholds but... how do you have those when 99,9% of the time I run Ubuntu on it and not XP ? I have the XP on it *only* in case I cannot do my job with Ubuntu

So, anyone have ideas how to setup battery thresholds on T61 running Ubuntu?

 

On the x200, the thresholds are written to the battery itself (or perhaps a hardware controller). This means, that if you set the thresholds in XP; Ubuntu (or any other OS, or a turned off computer) will respect them (if I plug it in at 71% running Ubuntu it just sits idle). The implementation is flawless and I am amazed it works as well as it does. Hopefully it works as well on the T61 (I could never get it to work right on my T40).

 

Thank you for this tip! I did as you suggested - booted windows, set the thresholds, shutdown properly and now use it with my (usual) ubuntu

Currently running at 28% and charging - will observe if it behaves as you suggested it should. Tomorrow will report back for reference of users who like to search before they post new topics

EDIT > Couple of hours later, back to report that IT WORKS, just as jonlumpkin suggested!
Booted windows, set it up, clean shutdown - now using Ubuntu respects the thresholds I set. Awesome, absolutely legen-dary!