A valve regulated lead‐acid (VRLA) battery, commonly known as a sealed lead-acid (SLA) battery, is a type of lead-acid battery characterized by a limited amount of electrolyte ("starved" electrolyte) absorbed in a plate separator or formed into a gel, proportioning of the negative and positive plates so that oxygen recombination is facilitated within the cell, and the pres. The first lead-acid gel battery was invented by Elektrotechnische Fabrik Sonneberg in 1934. The modern gel, or VRLA, battery was invented by Otto Jache of in 1957. The first AGM cel. Lead-acid cells consist of two plates of lead, which serve as, suspended in an consisting of diluted. VRLA cells have the same chemistry except that the electrolyte is immobilized. In AGMs, this is acc. Each cell in a VRLA battery has a pressure relief valve that will activate when the battery starts building pressure of hydrogen gas, generally a result of being recharged. The cell covers typically have gas diffusers built into them, w.
