[Al Skierkiewicz]

Andy,
The batteries we now use (AGM) can theoretically be used and charged in any orientation including upside down. Personally, I recommend that they be charged in an upright orientation, although laying on their side is OK too. I still frown on charging upside down to keep the seals from expelling electrolyte or other liquid in that case where the seals may open. The batteries are designed to be recombinant such that what free moisture may be present will readily be combined and thus retained by the glass mat. In the upside down orientation, I believe this will occur much slower than in the right side up orientation.