Batteries, Heat & Rust

So I'm now officially 3 years into my battery pack and it is showing signs of needing to be replaced (I think). I did run across this tidbit from EVamerica:

Battery Additive

Last month, we reported that Steve on Martha's Vineyard doubled the range of his 3-1/2 year old batteries by using an additive. The range increased from 10-13 miles to 23 miles per charge. Now, a month later his range increased to 40 miles. Steve says part of the increase is due to warmer weather. The cost was $80. The website was:
http://www.chinadepot.com/batripod.html

Note: EVA does not endorse or make any claims about the effectiveness of the above products. We simply share the experience of our customers.

As I am not inclined to believe you can put a magical potion into the cells and voilà, your battery life is extended for a few months/years, it is enticing to think I could spend $80 and not $1800. Anyone have any suggestions on what to do - recondition? replace? suck it up and go EV a la Flintstones?

On another note, I've got to repair a bit of rust on the undersides of the doors and repaint the whole car. The car floor is holding up great (a recurrent problem in the Northern climates with VWs) and again (like I said many times here) the car just keeps running without any real need for maintaining it. Someone once compared it to a ceiling fan and that is about right - how often do you have to replace that motor, maintain the electricals and think to yourself "is today the day when I flip the switch it won't come on"?

Hopefully in 3 more years I'll be still driving this obnoxiously orange wagon, only then I hope to use lithium batteries.....