AGM batteries have different charging methods compared to any traditional batteries. But we all know that using solar panels is the cheapest way to charge a battery.
Here comes the question “Can I charge an AGM car battery with a solar panel?”
Well, you can charge your AGM car battery with a solar panel. But you must know how to do it. Without the proper knowledge, you may damage or explode the battery which you don’t want at all.
Charging the AGM battery is not rocket science and you can do it without taking help from others. But there is a right way of doing everything. Let’s check them below.
The process of charging a battery with a solar panel
The process of charging a battery with a solar panel is described below.
Checking the wattage of your panel
The wattage of your solar panel indicates the power of your solar panel in watts. If your solar panel is attached with a sticker that says “300W,” its power is 300W. However, sometimes these stickers or information aren’t attached to your solar panel. In that case, you have to calculate it. To do it,
- Hold a multimeter in your hands.
- Now attach the red pointer to the positive side of the panel and the black one to the negative side of the panel.
- Make sure to use the multimeter in sunny weather.
- There should be a dial on the multimeter. Toggle it to the wattage section.
- Now check the number on the multimeter to know the power of your solar panel.
It is essential to check the power of the panel because if you don’t measure it properly, the battery may start storing more power than its capacity. As a result, the battery can get damaged.
Checking the amperage of the solar panel
You need to check the amp of the solar panel before buying a charge controller. When choosing the charger controller, you should choose one that can handle that much electricity. To do it,
- Test the power of your solar panel with the help of a multimeter.
- Check the voltage of your battery.
- Then multiply these two numbers.
The result of this multiplication is the electricity from your solar panel.
Choosing a charge controller to get better energy efficiency
The charge controller controls the charging of a battery. As a result, the battery doesn’t get charged too much. It also controls the discharge rate of the battery. Two types of charge controllers are available on the market.
PWM
The PWM model is the cheaper product. You can use it to regulate the voltage of your battery as much as you want.
MPPT
They can also regulate the voltage of the battery. But they can do it more effectively and can store the energy better. As a result, it can provide 30% more energy efficiency. That’s why it costs more than PWM. So you should choose an MPPT charge controller according to the power and electricity of your solar panel.
Placing the charger controller in the right spot
The charger controller must be placed in the right spot, or it can get damaged because of weather conditions. It is not weatherproof, so heavy rain or too much wind can damage its inner controller. That’s why:
- Put it in a place that is permanently mounted.
- Cover it with non-conductive materials like PVC, wood, or rubber.
- Use wires to connect the charge controller with the solar panel.
Connecting wires to the battery
Usually, positive and negative wires are pre-attached with the batteries. However, if your battery doesn’t have it, you have to attach it first. To do it,
- Hold a red wire in your hand.
- Then slightly cut the outer layer of its body so that the copper inside it can get out.
- Place the copper wire on the positive post of your battery.
- Start twisting the wire around the post until it is attached perfectly.
Then take a black wire in your hand and do the same job on the battery’s negative post. You can use different colored wires. You must choose them in such a way that you can later understand which is positive and which is negative.
Attaching another side of wires with the charge controller
You need to attach the other side of the wires to the charge controller to control the power distribution of the battery. To do it,
- Again, hold the other part of the red wire.
- Cut its outer layer.
- When the copper part comes out, slide it into the corresponding ports.
- Hold a screwdriver in your hand.
- Use it to screw the wire tightly.
- Do the same process with the black or negative wire.
You should choose wires according to the voltage of your battery. Usually, for a 12-volt battery, you have to use 10-gauge or 12-gauge wires. If you don’t use exact wires, they can short circuit.
Using an MC4 connector to connect wires
You need to connect the wires to the charge controller by using an MC4 connector. It has two different sides. One works on the male side, whereas the other one works on the female side. To do it,
- Insert the wires into the MC4 connector.
- Attach the other side of the wires with your charge connector.
- There must be an area called “input ports.” Look for it.
- If you get it, insert the wire into that port.
- Use a screwdriver to screw the wires perfectly into the port.
Connecting the controller to the solar panel by using wires
Now it is time to connect the charge controller with the solar panel. You have to use the two open ends of the wires for this purpose. To do it,
- Take the male port of the Mc4 connector in your hand.
- Match it to the right place on the solar panel.
- Now insert that port.
- If you hear a slight noise, it means you are perfectly connected.
- Do the same process with the female port.
- Check to see if you connected the correct port to the right place or not.
If you connect perfectly, you will see numbers like voltage, power, or electricity on the digital screen of the charge connector. You haven’t connected the wire perfectly if you see “0” on the screen. So recheck every wire and connect it properly.
You need to attach the battery to the connector until it is adequately charged. You may wait longer if the weather isn’t sunny or if your battery is big-sized. Also, you can get information on charging by checking into the digital screen of the charge controller.
You can also check – How Do I Charge An AGM Battery From An Alternator?
My two cents for you
Charging your AGM battery properly is more important than using it. The lifespan and charging capacity will depend highly on how you charge it. And when it comes to charging with solar panels, you need to be extra careful.
You know the answer to “Can I charge an AGM car battery with a solar panel?”
But knowing how to do it properly is more important. Make sure you follow the steps with top-notch care and security to get the best result out of your AGM battery.