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What are the best batteries to use in solar photovoltaic systems: Monoblock, AGM, Stationary, GEL or Lithium?

If you are looking for a photovoltaic solar system with back-up battery, that is, to store the energy produced during the day for later consumption, instead of dumping the excess produced into the electricity grid, you should know which types of batteries exist.

The batteries that store electricity can be monobloc, AGM, stationary, gel or lithium. As you can see, there are several types of batteries that you can connect to your photovoltaic system and thus store the energy that you produce the most.

But it helps to know what each of them means, as well as how they were designed. Not all types of power generation are suitable for a battery.

Main types of batteries.

Monobloc batteries.

This type of battery is designed for small photovoltaic installations where the price-performance ratio is balanced.

They are reinforced with special insulation, so there is little water loss. They are recommended for closed systems, telecommunications, signaling installations or repeaters.

AGM batteries.

AGM (Absorsent Mat Glass), have gas valves for the best recombination of the same. In this way, energy losses are avoided, the internal pressure is regulated in a simpler way and for this reason there is a greater use which results in a higher performance.

AGM batteries are suitable when you have high currents in a short period of time, because their internal resistance is very low. This is why they are better suited than gel batteries for high current discharge situations.

Gel electrolyte batteries.

This type of battery provides high quality cyclic operation, making it ideal for medium / large sized installations where the purpose of operation is long periods of time.

They are also suitable for systems that are difficult to maintain.

The gel component is due to the mixing of the electrolyte with silica, which then remains with the consistency of the gel.

Stationary batteries.

This type of photovoltaic solar battery is perfect for installations with continuous daily consumption and for long periods of time. Batteries with a lifespan of more than 20 years!

They allow important daily discharge cycles, with excellent results for any type of consumption.

Lithium batteries

Lithium batteries allow complete discharge, i.e. 100% of their power. For example, a 200Ah lithium battery can be charged to 100%, unlike others like AGM or gel do not allow charges above 80/90%, so they do not fully discharge.

And it is this feature that makes the charging process faster than other types of battery. In addition, it allows several discharge processes (up to 6000 cycles at 90%).

Another advantage of lithium batteries is their internal management system and uninterrupted service. In other words, they have an independent power supply which is activated in the event of failure of the main power supply.

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