Thinkpads Forum

Hello everyone, I was just wondering what was the original battery life for the IBM 365X, or any similar laptop (P1 120mhz, 810MB HD, 72MB EDO RAM, ~10-11 inch TFT screen).

The battery is now dead (only lasts 10-30 seconds), but it is a Ni-MH rated at 9.6v amd 2800mAH (2.8AH).

However, replacements are available on eBay (and other online stores like Batteries.com, but eBay seems the cheapest) for $36 + $10 shipping. These batteries are rated at 4000mAH, a ~40% increase in capacity. I just want to guage how much longer this battery will last compared how long the original battery lasted when it was new. I got the laptop with the battery already dead, so I have no idea on the original life.

Additionally, I was thinking that I could get 8 AA nimh (around 2500mAH, not very far from the original 2800mAH) batteries to replace the nimh cells in the IBM battery pack.


I opened the battery a while ago, and it's actually 8 batteries (size 4/3A) connected in parallel, along with some basic overheating/overvoltage protection.

I vaguely remember getting about 3 hours on mine when new... but that was 9 years ago, so ... ??

Thanks for the info.

So technically, if the battery scales linearly, then we should be seeing about 4.25 hours on a brand-new 4000mAH battery.

It also means if the laptop battery is rebuilt using 2500mAH cells, we should still be able to get 2.67 hours of use out of it per charge. That's still not bad, considering that's about the life of (or even a little better than) many new midrange/low-end laptops.

I'll let everyone know how it goes *if* I decide to buy or rebuild the battery.