So we tried in vain to revitalize several different laptop batteries per this article from HackADay:
Battery Revival:
The batteries on laptops are often a problem. Most people sit their
laptop on a desk and use AC power, so the battery usually suffers, resulting in
a chemical 'memory', which gives them a life of about 3 seconds under load. The
batteries in my donor laptops were both made in 2000, so I had to try and revive
them. If you have any NiCd or NiMH batteries that won't hold their charge, you can
often revive them. This is not a new concept, but here is my recipe for reviving
rechargeable batteries:
Discharge the battery as much as you can.
Place in a sealed plastic
bag.
Place the bag in your freezer for at least 24hours. Overnight is
sometimes enough, but I leave it about a week.
Take the bag out of the freezer and leave the battery to return to room
temperature. Make sure you wipe off any condensation from the battery contacts
before you use it. I just leave them in the sun for a few hours.
Fully charge the battery, then run it down again, as low as you can get it.
Repeat this charge-discharge cycle a few times, and see if you get a longer
life.
Your mileage will vary, but two of my 5-year-old batteries are now useful.
I get between 2 and 4 hours from one of them, depending on the load on my
laptop. You can do this with cellphone batteries, or batteries from lots of other gear.
We not only didn't revitalize any of the four batteries tested - they all completely crapped out after the exposure to extreme cold - (I think in my highly scientific hypothesis :) )
Verdict: Don't do it!
