Battery: Learn how to charge it at home?

Battery: Learn how to charge it at home?

June 19, 2021 Off By Rob Prosser

Probably every car owner has faced the problem of low battery. This disturbance can happen to any driver if you do not pay enough attention to the car’s power source.

We’ll talk about why car batteries discharge, as well as charging features at home.

Why is the battery empty

Typically, the lifespan of a modern car battery is 5-6 years, provided it is used properly and maintained in a timely manner. After that time the power is consumed and it is almost impossible to restore it.

However, it often happens that even a relatively new battery stops working. There can be several reasons for this:

  • the car stood motionless for a long time, especially in the cold season;
  • the insufficient amount and density of electrolytes in cans;
  • malfunctions of car electrical equipment;
  • destruction of battery worktops, etc.

If the car does not move for a long time, the battery is discharged without charging. This happens especially quickly in the cold. It is enough for the car to stand like that for two or three weeks and you will not be able to start it anymore

During battery operation, the electrolyte evaporates slightly. And if you do not control its amount, over time it will lead to the fact that the battery will lose its properties.

Various electrical problems can also cause discharge. This can be a short circuit, lack of charge, caused by a generator malfunction, etc.

In case of destruction of worktops, it is better not to use the battery – this can cause an internal short circuit, which is fraught with the failure of other electrical equipment, and even a fire.

How to prepare a rechargeable battery

If the battery is still discharged, do not rush to service. You can charge it yourself, of course, if you have a charger, plus you know how to charge the car battery. But first, it must be ready for that.

It must first be removed from the car by separating the terminal. If it has been out in the cold for some time, it must be taken indoors before charging and allowed to warm for several hours.

You can charge it at home without taking it out of the car, but this should only be done in a dry and warm place, preferably in a garage.

If it is working properly, you need to unscrew the cans and check for electrolytes before charging. Top up if necessary. And only then, without twisting the plugs, start charging.

And so on. Before charging it with a charger, you need to know its capacity. It is usually indicated on the label and is measured in ampere-hours (Ah, A / h). This value is required to calculate the optimal charging current.

A few words about security measures

Before charging the battery at home, it is helpful to learn a few simple rules that will protect you and your loved ones during this process.

  • First, the room in which the charging will take place must be well ventilated. Vapors released during the process (sulfur dioxide, hydrogen, etc.) are not safe for health.
  • Second, it is forbidden to charge the battery near open flames and heating devices.
  • And thirdly, any charger works from the network, so it is not recommended to leave it unattended for a long time.

Charging methods

There are three main ways to charge the battery:

  • constant voltage (voltage 14.5-16.5 V with a current drop of 45 to 20 A);
  • constant current (charging current is 10% of battery capacity);
  • combined method (first DC and then DC voltage).

After selecting the optimal DC voltage option, you will need to wait 24 to 48 hours. In the first case, the charging voltage is set to 16.5 V, and in the second – to 1.4 V. During charging, it gradually “gains power”, equalizing the difference between the battery and the charger.

The DC method allows you to charge it at home in 10 hours. Here it is important to accurately determine the charging current. As already mentioned, it should be equal to one-tenth of the battery capacity. In other words, if the battery capacity is 55 A / h, you must set the charging current to 5.5 A. In that case, when the battery voltage reaches 14.4 V, it must be reduced to 3 A, and to 15 V – to 1, 5 А.

The combined method combines the first two and is considered the best today. There are special automatic chargers for this method that can be used without constant supervision.

If you do not want to find out how to charge it with the charger using the methods described, use the tips below to charge quickly and completely. They do not require special knowledge in the field of electrical engineering, so they are suitable for beginners.

Fast charging mode

How much to charge the car battery? There is no definitive answer to this question. Each case will take a different amount of time. It usually takes 12 to 24 hours to fully charge. However, charging it at home can be faster. This, of course, is not entirely true, but if you don’t have time to wait, use the quick method.

To do this, you do not have to remove it from the car, it is enough to disconnect it by removing the clamps. Unscrew the lids of the cans (if it is a serviced battery), check the amount of electrolyte. If necessary and possible, add it.

Then we connect the charger terminals to it, strictly respecting the polarity. Only then can you connect to the network. After switching on the charger, we set its maximum value with the current regulation.

After 30 minutes the charging stops. This time is quite enough to charge the correct battery and it can start the engine. Further charging is the job of the generator, unless, of course, we are dealing with electrical equipment failures.

Full charge

If you have time, it is best to fully charge the battery with a low current. This method will allow you to charge it at home in gentle mode to the maximum.

Remove it from the car, after disconnecting the terminal. We install it on a flat surface. We unscrew the plugs, check the electrolyte. We connect the charger terminals, not forgetting to observe and check the polarity. Connect to a 220 V main and set the charging current to 10% of the battery capacity. We leave for 10-12 hours, not forgetting to check the progress of the process.

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