Install solar batteries, in parallel or in series?
Today we are going to talk to you about the differences between installing a solar battery in parallel or in series, a topic that usually generates many doubts among our clients. In addition, we will tell you what problems are associated with batteries connected in parallel and how these can affect the photovoltaic installation over time.
How to connect solar batteries
Now that you know the different solar battery types, the moment of truth arrives. How is it better to install solar batteries? This may depend on various factors, but there are a number of things that should be known before making the decision to install a solar battery in parallel or in series.
Install solar batteries in parallel, yes or no?
The first thing is that no two batteries are the same. Aspects such as manufacturing, storage or transportation, can mean that the same battery models do not have the same characteristics between them. Therefore, even if you buy several batteries at the same time, and they are connected in the same way, the most normal thing is that they do not have the same characteristics, since they decompensate over time.
The objective of installing a solar battery in parallel is to increase the storage capacity of a solar battery. To do this, two or more batteries are wired together, joining (+) to (+) and (-) to (-). On two batteries of the same size, this connection doubles the Ah capacity, but keeps the voltage the same.
By installing solar batteries in parallel, we create a closed circuit between the different batteries, which causes an imbalance of currents, given the differences between the equipment, which circulate from one battery to another to try to balance them.
Unbalance currents occur permanently, even when there is no consumption connected. This causes the batteries to wear out faster and their useful life is shorter. This problem with the imbalance currents of the batteries will damage them even more as the difference between the batteries increases.
Another problem with installing a solar battery in parallel is that there is a constant circulation of energy between the batteries, which can cause the charge to never be completed to 100%.
Also, if a battery is damaged, manufacturers are not usually responsible for problems that arise from poor installation.
Possible failures to connect batteries in parallel
When solar batteries are connected in parallel, the following faults may occur:
They can go from being downloaded to being charged at an unusual speed
If any batteries are worn out it can cause the capacity of the battery pack to be less than it should be.
For all these reasons, it is only recommended to install solar batteries in parallel when they are identical and are connected with wiring of the same dimensions, which is difficult to achieve.
To increase the capacity of a solar battery, it is best to change it for one with a higher capacity, or have two separate installations, between which there is no type of connection.
Although there are exceptions. For example, lithium batteries have electronic control and communication systems that allow better installation in parallel.
Advantages of connecting solar batteries in series
To connect different batteries in series, the positive pole of one element is attached to the positive pole of the other. This allows us to increase the system voltage and keep the amps at the same level as individually. Therefore, as the voltage increases, the capacity of the batteries also increases.
The series connection of the batteries will allow the passage of current only when there is consumption. When there is no consumption, the batteries remain at rest.
To get the voltage energy we need, we must connect batteries in series with the same capacity. In this way we add the voltages of the different equipment.
When changing the battery voltage, it may be necessary to change the regulators and inverters of the photovoltaic installation.
Recommendations on the installation of solar batteries
It is not recommended under any circumstances to connect a new battery with an old one. Since with the passage of time, the older batteries are damaging the new ones and modifying the charging voltages of the most recent batteries.
Having a solar charge regulator will help you control the level of charge that goes from the solar panels to the solar battery. When the solar accumulators are charged, the function of the charge regulator is to prevent the solar panels from overloading the accumulators and deteriorating them.
Solar batteries or accumulators need special care in their handling, since they can be dangerous if they are handled or installed improperly. That is why it is always advisable to have a professional team, which installs the solar batteries and advises you on the best connection between accumulators.
Buy solar battery at Varisolar, distributor of equipment for solar installations
At Varisolar you will find all the necessary components for your solar installation, including solar batteries.
We put at your disposal a team of professionals who will advise you at all times on the products you need to supply your home, premises, caravan or ship with energy, depending on your needs.
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