I've been using a home-made version of the Prestone
jumpstart battery for a couple of years now and have
taken it on many trips in the Westfalia to power
lights, radios, and whatever else so I wouldn't have to
worry about draining the starting battery. I picked up
several used 6 volt sealed lead-acid gel cell batteries
from an electronic surplus store for only a couple of
bucks apiece. These are pull-outs from applications
like backup power for burglar alarms, but I tested each
battery with a load (a taillight bulb) and a voltmeter to
screen for good ones. I taped two of them together, wired
them in series, put on my standard connector (the Radio
Shack two-pin molex one) and have 12 VDC anytime
I need it. Most of the cells are 10 amp-hour, but I have
a couple of smaller ones, too. I bought an easy-to-build
smart lead-acid charger kit for about $50 that won't over-
charge the cells to prolong their life. It's a great setup
that can provide a lot of versatility for those camping
and road trips.

- Scott
  former owner '91 Westfalia Camper