VRLA Batteries: Maintenance-free batteries for backup power systems. 

VRLA stands for Valve-Regulated Lead-Acid batteries. These are a type of sealed lead battery that has a safety valve to release pressure in case of a fault. The "sealed" design means they do not require the regular addition of water, making them maintenance-free. There are two main types of VRLA batteries: Absorbed Glass Mat (AGM) and Gel Cell.

AGM batteries use a fine glass fiber mat to absorb the electrolyte, keeping it suspended between the lead plates. This design allows for a quick reaction between the electrolyte and the plates, making them ideal for high-current applications like starting an engine.

Gel cell batteries use a silica additive to turn the electrolyte into a thick, immobile gel. This design offers better resistance to vibration and extreme temperatures and is less prone to damage from deep discharges.

VRLA batteries are a great choice for applications that need a reliable, maintenance-free power source, such as uninterruptible power supplies (UPS), solar power systems, and mobility scooters.