I wonder if there was an issue with the batts prior to the storage. I have used a batteryminder on known good batts for 2 winters now and there was little, if any, water gone in the spring when it was time to reinstall.
Quite possible, dznf0g. The abnormal loss of electrolyte could have been a defective battery.
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Safe Travels,
Joe & Joan Donnaway
Durango, CO
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