How Long Does It Take to Charge 12v Battery With Solar Panel – Overall Review For 2021

The common problem of this whole world is pollution. Global warming and greenhouse effects are everywhere and the main reason of this is burning of limitless fossil fuel to produce energy, with the increase of population fossil fuel burning is increasing.

The evolution of solar power technologies is appraise to be one of many key solutions toward fulfilling a worldwide increasing demand for energy. The world population and demand for energy is increasing proportionally. To satisfy this increasing demand, solar energy is like a blessing to us.

What Is Solar Energy

Solar energy is the energy that we get form the sun. This energy is the form of solar radiation which is the process of renewable energy. Which makes possible the production of solar electricity.


Through this process electricity can be produce directly form photovoltaic, PV cells. Solar photovoltaic (PV) devices, or solar cells, change sunlight directly into electricity. Solar energy mainly produced during sunny hot day and most importantly it has no emission.

What Is Solar Panel

We all know that sun is the ultimate source of energy and device that converts sunlight directly to the electricity is called solar panel. A solar panel is the combination of small solar cells spread around a large area and work together to produce enough power to be useful.

The more sunlight penetrates to the panel the energy will produce. On the other hand solar panels are efficient as well DS1’s solar panel capable of converts 22% of their available energy into electric power which is more than enough to fulfill daily house hold needs.

How does solar charger work

The demand of solar power has increased with another renewable technology which is solar batteries that can store extra solar power for later use. Solar batteries works by converting DC energy which is produced by solar panel and stores for later use as AC power.

The amount of stored energy mainly depends on the battery’s capacity. The higher your battery capacity the more it can store.

Using solar energy will help to have a better life. First of all, if we use the solar energy more often, our bills for electric power will be much lower. We will not be in the position where we will have to give the most of our money to pay those bills.

So. Using this solar energy will save our money. The second thing is pollution will decrease. This kind of energy can be converted into an electric one and can be used to charge some batteries that need electric charging. One of those batteries is 12 v battery. This kind of battery has a big capacity and it is usually used for cars that use solar energy.

How long to charge 12v battery with solar panel

To answer this question, we must know some of the factors that can impact the charging process. To know how long it will take, we must know how if the battery needs full charge or not. Also another important thing is the power of the charger. If the charger is more powerful, then you battery will be fully charged quicker.

If the battery gets hot while you are charging it, just stop the process. You have to remember that. This little detail ruined most of the batteries because people kept charging them.

How does solar charger work

Now, to determine the time needed to charge 12v battery with solar panel, you need to do some calculation through following steps:

Step One:

As we mentioned before, to know the time you need to charge your battery, you need to know how much reserve capacity it has. For calculations like finding the amount of A/h in the battery, you should multiply the reserve capacity of the battery by 0.6.

That means that if you have reserve battery with 100 minutes left, you should multiply 100 by 0.6 and you will get 60 A/h. This first step is very important because if you do the wrong measurement right now, the whole calculation later would be incorrect. So, this is an easy step, you will surely do it right.

Step Two:

To complete this step you will need a voltmeter. A voltmeter is a basic tool for measurements like the open circuit voltage of this kind of battery. When you read your voltmeter and it shows a voltage of 12.2 that means that the battery is charged about 50 percent, having a 50 percent charged battery means that there is about half of the 60 A/h.

Half of the 60 A/h=30A/h. This means that to fully charge the battery, it is necessary to put approximately 30 A/h + 20 percent more to recompense for the internal resistance for a total of 30 A x 0.2. That means that you will need 36 A/h to charge your battery to 100 percent.

Step Three:

Few more calculations and we are done. If your battery was charged at a rate of 10A but it needs to be replaced 36 A/h in the battery Well to make these calculations about how long will it take in hours to charge the battery, you need to divide 36 by 10. That means that you will need 3.6 hours to charge the battery.

The best charger for these kind of batteries is A 12v/10A3-stage automatic charger. But there is one little problem and that is that these charger usually do not output the whole amount of 10 A during the charging process.

They do not do it because it limits the voltage and the amperage. What you only see is approximately ½ the output over the period of time while the battery is in the middle of the chagrin cycle.

Because of that, the chagrin will not take 3.6 hours like we previously said, but it will take longer. Approximately, 12 hours. Sometimes even more, because of the reduced voltage.

Step four:

This step will if the battery is fully charged or not. To complete this step you will need to wait for the battery too cool down to room temperature. It is very important for the battery not to be getting very hot while the charging process because the heat could ruin it.

Also, if the battery is getting hot, that means that something is wrong with it and you will have to stop the charging process immediately. But now, after the heat of the battery reached the room temperature, you will have to use a voltmeter or hydrometer and go check the cells. That is how you are going to see if the battery is fully charged.


Giving the answer to only one question sometimes is not very helpful. We hope that with this article we helped more because we explained the way of calculating and determining the time by yourself.

So, later if you would like to know how much time you will need to recharge your battery, but the amount of how much reserve left is different, then you will just have do the measurements and the calculations, follow these few steps and you will get the precise period of time.

There are different batteries, different chargers and different conditions where the battery can be charged and that is why you cannot just give a general answer. Generalizing happens to be wrong most of the time.

Team Chooserly

A passionate blogger! Editor at Chooserly, and a regular author at HuffingtonPost, LifeHacker & Forbes!

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