Thinkpads Forum

T400, bought from Microcenter in CA about two weeks ago. The battery was fine (although would last only about an hour or so) and the the system works great (it is in pristine condition cosmetically). What I did was to unplug the system from the power source and not used it for about 8 days or so. When I connected the source and booted the system, it never charged the battery.

The battery manager utility reads:

Cycle 15, first used 2009-2, and it shows a "good" battery in the utility, but Lenovo Battery icon reads 0%.

When the system reboots, or wakes up after sleep, the Windows 7 charge icon in the task bar animates for about 10 seconds, then stops.

It is the battery or charger?

OK, I exchanged the battery, this one is the kind that has an extra cell and the manufacturer is Panasonic (cell made in Japan). They took it out of an unopened T400 (still refurbished) box. It was a bit dusty, but after complete cleaning, it works like a charm now. The cycle count reads 31, first use date still 2009-02.

You got lucky. The Panasonic cell batteries are about as good as it get.

Thanks for your comment. It certainly seems that way, as it is charged up to 90% now (from initial 77%, about half an hour ago).

Two questions:

1) What is a cycle count? (the number of being charged?)

2) So are these batteries (with a protruding cell) theoretically has more capacity compared to the regular ones (which flushes with the the length of the system).

Cycle count means the number of times the battery have been discharged and recharged. It's can be an indicator of wear but it's not the be all and end all. Other factors affecting wear is date of manufacturer, date of first use, usage conditions, storage conditions, type of cell (Panasonic are most desirable), etc

The physical size of the battery is typically dependent on the number of cells that are inside the battery. The greater number of cells, the greater the capacity. Typically laptop batteries are made in 4, 6 or 9 cell packs. Sounds like you got a 6 cell battery as the 4 cell battery will sit flush with the back.

Thanks for your answer!

Should I disconnect the power, when the battery reached 100% charge? Everytime I do it, my cycle counts goes up! If you keep the power source plugged in, will it decrease the life of the battery?

Yes it will, you need to let the battery charge 100% then discharge to a 10%, i know it can be annoying but from personal experience you have to do it, ive been working in computers for years now i work at company that sells mostly lenovo in tustin, CA and i know the microcenter here is cali they are not that bad, but anyways whether you buy original or third party and you dont let it charge and discharge it will die sooner, thats what happened to my R61i after 10months it will hold less than 30mins.

That's what I have been doing, thanks for confirming my method. I also happen to own a R61i (and many T22s!)

Using Power Manager, I set it the charge when capacity is 70% or lower and only charge to 97%. Typically though I'll let it discharge lower than 70% before I'll charge it again. Don't really care about cycle count. AFAIK Lithium-Ion batteries don't like the extremes (low or high capacity). Regardless of what you do these batteries will degrade over time.

OK, I gauged my battery from the time I unplugged it from the source (100%) till I get the 10% warning message:

It lasted about 2:10 hours.

Is this a good?