The main feature that distinguishes an AGM VRLA battery from a conventional one is the gas recombination technology. In a conventional lead-acid, free-acid battery, the dissociation of water into hydrogen and oxygen occurs during the charging phase. The two gases escape from the caps, while the electrolyte level inside the battery decreases. An AGM VRLA battery, on the other hand, exploits the recombination principle. Thanks to a special microporous separator (Absorbent Glass Mat), impregnated with a controlled quantity of electrolyte, the oxygen released from the positive plate following the dissociation of water, during the recharging phase, can migrate to the negative plate, from which it is fixed and then recombines with hydrogen, restoring the water that had dissociated. A closed electrochemical cycle is thus established, in principle, without any gas emission to the outside world and without water consumption.
AGM VRLA technology is ideal for applications requiring maximum starting current, extreme resistance to charge and discharge cycles, no maintenance and no liquid or gas leakage.

HOW DOES AN AGM BATTERY WORK?

On hermetic lead-acid batteries, AGM batteries, we often find the abbreviation VRLA, which literally means ‘Valve Regulated Lead Acid’.
This information is intended to indicate how the battery was made.
Inside AGM batteries there is a valve that automatically renews energy production without having to fill the battery with acid. If the battery is marked AGM (Absorbed Glass Mat), this means that there are glass fibre plates inside that absorb and retain the acid.
In their normal state, AGM lead-acid batteries have a gas recombination system inside them. The valves then have the task of releasing gas in the event of an overcharge. AGM plates therefore reduce the production of gas by transforming it into water and redistributing it in the internal circuit to produce current.
AGM technology thus makes it possible to have a hermetically sealed battery without any possible leakage. Should the battery fall, the acid will not leak out.
AGM batteries are also maintenance-free: unlike lead-acid batteries, they do not require regular additions of electrolyte.

ADVANTAGES AND DISADVANTAGES OF LEAD-ACID AGM BATTERIES

All technologies used to make lead-acid batteries have advantages and disadvantages. Before choosing one technology over another, it is necessary to bear in mind the type of use of the battery and the appliance on which you want to install it. Do not forget that each appliance has its own technical characteristics and requires a certain type of energy in order to function at its best.

ADVANTAGES

• Ideal for buffer charge applications (permanent mode)
• Maintenance-free
• Virtually zero environmental impact, lead acid is 99% recyclable
• Economical, the price of AGM lead-acid batteries is much more competitive than other technologies

DISADVANTAGES

• Not always suitable for intensive cyclical use
• Not all models are designed for deep or total discharge
• Charging processes must be precise in order to avoid cycle shortening and overcharging