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VRLA – Valve Regulated Lead Acid

Valve Regulated Lead Acid batteries are sealed lead-acid.

They include Absorbed Glass Mat (AGM) and gelled electrolyte (GEL) type, both of which have the following characteristics:

  • Sealed using special pressure valves and should never be opened.
  • Non-spillable , and therefore can be operated in virtually any position (except upside down).
  • Is completely maintenance–free, does not need topping in service life.
  • All of the electrolyte is immobilized (absorbed in AGM or fixed in Gel structure).
  • Uses recombination reaction to prevent the escape of hydrogen and oxygen gases which are normally lost in flooded lead–acid batteries.
  • Non-spillable , and therefore can be operated in virtually any position (except upside down).

GEL – In addition to the characteristics of VRLA, GEL batteries:

  • Use thixotropic gelled electrolyte, it is in a solid state between the plates and separators.
  • Unlike traditional AGM electrolyte "starve" designs, GEL batteries have 15 – 25% more electrolyte volume than AGM type.
  • Utilize different separator material such as PE, PVC, etc.

Differences between GEL batteries and AGM batteries:

  • Both are sealed recombinant batteries. Both are sealed valve-regulated lead-acid (VRLA). AGM batteries and GEL batteries are both considered “acid-starved” and the electrolyte does not flow like a normal liquid.
  • The gel electrolyte has the consistency and appearance of petroleum jelly. Like gelled electrolyte batteries, AGM batteries are also considered non-spillable as all of the liquid electrolyte is trapped in the sponge–like matted glass fiber separator material.
  • Due to the physical properties of the gelled electrolyte, gel batteries have higher internal resistance.
  • AGM batteries have excellent performance for high current/power discharge and GEL excels in higher/lower temperature stability and lower current/power discharge applications.
  • AGM batteries have higher specific energy density than GEL batteries, but GEL batteries have longer service life.

Ritar MSDS