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MEXICOWANDERER's avatar
Mar 18, 2018

AGM Batteries Do Not "Dry Out" Unless Physically Damaged

  • AGM batteries do not dry out unless violently mistreated
  • The batteries are sealed
  • Special battery caps recombine oxygen and hydrogen and precipitate it back onto the glass mat
  • Special relief valves built into the cap maintain pressure within the battery until a threshold is reached
  • The caps then pop open, release pressure then automatically reseal: In practice it takes upwards of high 16's into the 17's of voltage to build up enough pressure to cause venting
  • Prolonged excessive charging causes positive plates to shed
  • It is because electrolyte in an AGM is extra potent 1.300 that the battery is sensitive to excessively high voltage.

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