Service life of AGM battery
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Unlike the previously used lead calcium batteries, the sulphuric acid contained in batteries with fleece technology is not self-contained in the battery housing.
Instead, the sulphuric acid is 100 % bound up in glass fibre fleece mats (separators). Thus, no acid can escape if the battery housing is damaged. In addition, the AGM battery is sealed gas-tight. This is possible because the gases are converted back into water as a result of the separator permeability.