Is there any way of bringing old batteries back to life?

I mean one that has no cracked plates, rather has just been sitting flat for a while. One that does not hold charge, and only gasses when a current is put through it.

This question has always plagued me, and I would love to find out if it is possible.

Cheers
Tnate

apply current(cy)
a new one fixes sulphation--------

Once a battery is stuffed, there's no turning back. Application of a sufficient amount of currency is the only way to fix it. It makes the battery like new!

Even if you can get it to hold enough charge to crank the car, try it a little later. It'll be dead again.

I'll be pursuing this method in the near future.

Battery conditioner to keep new batteries good and reduce sulfidation.

http://www.inox-mx3.com/product_detail.php?productID=2&pageID=APPLICATIONS 

Tip the acid into a plastic container. Go to your neighbours house and use their garden hose to hose out the battery to remove most of the buildup from the plates. Put the acid back in and charge the battery fully.Presto. Make sure you use your neighbours hose as it will kill the grass. And yes it does work.

Wow. really? I'm genuinely surprised.
The last place I lived had sulphuric acid in the general store. Don't suppose it's sold like that here, is it?

Motorcycle shops sell battery acid because bike batteries are sold dry.

So, how much of an old battery's life can be reclaimed? I just need mine to hold enough charge to crank properly....and hold a charge. Probably easier to get another one. My batteries are pretty old now.