Lenovo S10 battery issue with Peppermint 6?

Had Peppermint 5 on a USB and used it to boot-up on my Lenovo S!0 .

Decided to install Peppermint on my HD, as XP is no longer supported and Peppermint is LTS.

Noticed the netbook tus off immediately after removing AC cord. Wondering if my battery is just spent or are there known issues w/ Peppermint battery driver/s?. Don't know how to test a battery either although i'm thinking that it could be done w/ some kind of electrical meter/reader of some sort??? My battery only held less than 30 mins charge last time I checked, over a year ago, and I've kept it plugged into the wall.

My netbook model is type 4333-36U produced in 2011

I installed Raspberry 6 on it as it was mentioned that Peppermint is one of the better flavors for laptops w/ little computing power (CPU's) such as netbooks