replacement extended 9-cell battery experiences

[Ogg]

Just wondering.. what are the experiences from some of you who have purchased 9-cell replacement batteries for your T40 's and have used your laptop on battery power fairly regularly? Is 2 years a reasonable time to still expect about 20% capacity?

I've been generally pleased with the performance of my battery which I've had since March 2009. Now nearly 2 years old, it's down to about 20% capacity (less than one 1 hr). When I first received it, it provided about 5hrs run-time. After about 8 months, that tapered down to about 4 hours, and remained somewhat steady at that capacity for atleast 6 more months. About two months ago, the capacity dropped to 50%. Then, a month later it dropped to 30%. It is currently "steady" at 20% which barely offers 1 hr of use.

**************************** BATTERY INFORMATION
Remaining percentage: 33 %
Remaining capacity: 18.49 Wh
Full charge capacity: 57.70 Wh
Temperature: 29 C
Cycle count: 93
Manufacturer name: GW
Manufacture date: 2007-03-23
First used date: 2009-03
Serial number: 1388
Bar-coding number: 1ZB5S59W1DJ
Battery name (FRU part number): IBM-COMPATIBLE
Device chemistry: Li-Ion
Design capacity: 73.26 Wh
Design voltage: 11.10 V

I purchased mine from powermega.com

Item:
Code: CL741B-862
Name: Replacement (extra) Laptop battery for IBM ThinkPad T40 / T41 / T42 / T43 / R50 Series was specifically designed for your IBM NOTEBOOK COMPUTER and built to meet or exceed OEM's specification.
Quantity: 1
Price: CAD$ 66.34

Shipping was $16.

The same battery is currently listing at USD:$55.69, CAD:$58.48

I need to purchase a replacement. 20% remaining capacity just doesn't cut it. I see other replacement batteries at over twice the price. (eg. Tigerdirect.ca, BTI model, $122). Would this "BTI" brand last longer than the one I got from powermega.com? Or.. is another powermega.com battery at $58 + shipping a good deal for another 20 months?

What are some of your experiences and recommendations?

..Ogg.

[billp117]

Batteries don't last forever...you need a new battery. Some last longer than others and the Lenovo batteris are the best. You could have tried to cycle the battery a few times but I doubt you could make it work any better.

I have been buying after-market T4x batteries from this eBay seller with satisfactory results:

http://cgi.ebay.com/New-BATTERY-IBM-Thi ... 2eb22a965f

This battery has a smart chip and communicates with Power Manager-3 just fine. It even tells you when the warranty expires. Since they are a US seller I think any future problems would be easy to resolve. But since they sell for less than $25 your risk is low.

Good luck...

[Ogg]

Hi Bill.. I see that most of the batteries listed at that ebay seller are 4400mAH. How long did your replacements last?

I am specifically interested in the 9-cell, 6600mAH, extended types.

In the course of almost 2 years of use, I have purposefully cycled the battery twice. In the regular course of operating on battery power, some of the time I would run the battery quite low anyway. Most of the time time I would run the battery down to 50%-60% before I would plug it back on AC for recharge while I use the laptop.

[billp117]

It will last about 2.5 hours or more...depends on what you are doing and how you set the power manager.

B

[lead_org]

These generic batteries usually don't last long. The 9 cells generic version i got from China, lasted only one year, now it only holds about 1 hr of battery under battery saver mode.

[frankiepankie]

The quality of a battery depends on the brand of cells that are used. Batteries with Panasonic cells from IBM are VERY good, they seem to keep working forever (i have a battery with Panasonic cells in my T40 and after 311 cycles it still has 31Wh of it's original 47Wh capacity).

I don't know which brand cells those aftermarket batteries use, and what capacity that cells have.

[MnR]

Hi,

I have 9 cell batteries. I use IBM or BTI.

MnR

[Ogg]

My new 9-cell genuine IBM battery is now installed in my T40p. Nice thing is that the battery is "fresh"; the manufacturing date is Jan/'11. Will be interesting to compare this one with the previous off-brand battery that only lasted 2 years.