Why should photovoltaic off-grid systems be equipped with energy storage iron phosphate batteries?

Energy storage batteries are essential in the off-grid system. The solar panel charges the energy storage battery through the controller, and the iron lithium ion battery is output by the off-grid inverter for users to use. Energy storage batteries are commonly used in the photovoltaic off-grid system, such as iron phosphate lithium ion batteries and lead-acid batteries.

Photovoltaic off-grid system composition:

Photovoltaic modules, off-grid inverters (including photovoltaic chargers/inverters), energy storage batteries (lead acid/colloid/lead carbon/ternary lithium/lithium iron phosphate, etc.), photovoltaic brackets, cables, and distribution boxes are all important components of photovoltaic off-grid systems.

In photovoltaic off-grid systems, lithium-ion batteries storing iron phosphate account for a large proportion. Their cost is similar to that of solar modules, but their life is much shorter than that of solar modules. The task of lithium-ion batteries storing iron is to store energy, ensure the stability of system power, and ensure the load power at night or in cloudy and rainy days.

• Photovoltaic power generation time and load power consumption time are not necessarily synchronized.

The photovoltaic off-grid system, input is a component, used for power generation, output is connected to the load. Photovoltaic power generation is in the daytime, there is sunlight to generate electricity, often at noon, the highest power generation, but at noon, the demand for electricity is not high, many households use off-grid power station electricity at night, then how to do during the day, the energy storage device is to store iron phosphate lithium ion battery. Wait until peak demand, like 7 or 8 p.m., to release the power.

• PV power and load power are not necessarily the same

Photovoltaic power generation is affected by radiation, is not very stable, and the load is not stable, like air conditioning, refrigerator, starting power is very large, usually less running power, if photovoltaic directly with load, it will cause system instability, voltage rise and fall. The energy storage battery is a power balance device. When the photovoltaic power is greater than the load power, the controller sends the excess energy to the battery for storage. When the photovoltaic power cannot meet the load requirements, the controller sends the energy of the battery to the load.

• Off-grid systems are costly

The off-grid system is composed of photovoltaic array, solar controller, inverter, battery, load and so on. Compared with grid-connected systems, there are more batteries, which account for 30-40% of the cost of generating a system, almost as much as components. And the service life of the battery is not long, lead-acid battery is generally in 3-5 years, lithium ion battery is generally in 8-10 years, after the need to replace.

As the energy storage device of photovoltaic system, the energy storage efficiency of the new type of energy storage iron phosphate lithium ion battery can be increased to 95%, which can greatly reduce the cost of solar power generation. Lithium-ion batteries are 95 percent energy efficient, compared with about 80 percent for the lead-acid batteries commonly used today. Lithium-ion batteries are lighter and have a longer lifespan than lead-acid batteries. They can charge and discharge up to 1,600 cycles, which means they don't have to be replaced very often.