Valve-Regulated Lead-Acid Battery
A lead-acid battery that is sealed except for a one-way valve.
The one-way valve releases gas when the internal gas pressure in the battery exceeds the atmospheric pressure by a preselected value.
This makes it possible to produce batteries that do not leak and do not require maintenance. They can also be installed at an angle.
For VRLA batteries, the electrolyte is fixed either in gel or in fleece (AGM). Due to gas recombination, these batteries only emit a small amount of gas and therefore hardly any liquid is lost.