How to charge lead-acid batteries?

The situation is that when a beginner buys a 12V battery, he usually finds 12V charger for batteries in the store. However, difficulties come exactly when 6V batteries are bought, and the question is how to charge it?

Let’s just talk this through, together!

Each battery has its own label, which is printed on the battery or is in the instructions.

As we can see on our on our batteries, it says, Cycle use and standby use with a different voltage range.

What is this for?

Cycle use is the situation when you use this battery in a toy car or in a vacuum cleaner or somewhere remotely.

It means that you charged a battery, installed it in a device where it is discharged during operation, and then you put it to charge again.

Then you need to set the voltage for charging for 6V battery in the range: 6.75V-6.90V

Standby use is the situation when your battery is used as a backup power source, such as a UPC. When the main power supply is lost, the power is supplied from the battery.

Is it enough to buy a simple power supply? No!

Because we need to set current limits in addition to setting the charge voltage.

For example, you need to set current limits at a maximum of 1.5A for our 6V battery, and you need to set to 1.2A for 12V battery.

Thus, we need a power source where you can set the voltage values ​​that fall into the range you need for 6V or for a 12V battery.

And do not forget about the current limit.

How to do it?

The easiest way is to purchase a simple banggood module to which you can connect any power supply with a higher output voltage than you need to charge, and connect other terminals directly to the battery.

 OUT + to the red terminal, and OUT- to the black terminal.

However, the most important thing before you start to charge is to set the voltage you need and use the trimmer to limit the charging rate.

According to the best practice, the charging rate is set equal to 10% of the capacity.

For my batteries, it will be: 5Ah / 10 = 0.5A (best practics) and not more than MAX 1.5A!

A more difficult option for soldering fans is to use the well-known LM317 Linear Voltage Regulators or L200CV, the same Voltage Regulators with the ability to set the output voltage and current limit.

How long does it take to charge the battery?

You need about 10-12 hours for fully charging.

If you have an ammeter, you can put it in the open section of the circuit, which will allow you to see at what stage of the charging you are. When the charging process ends, your charge current will be about 5%.

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