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Can You Charge A Car Battery With Two Chargers?

As a car owner, you may wonder if it is possible to charge a battery with two chargers. Fortunately, we have done some research for you, and here is what we found.

Yes, you can charge a car battery using two chargers. But make sure the chargers support parallel operation. If not, both chargers could get damaged. 

It is important to know how to go about using two car chargers simultaneously safely. Keep reading to get detailed information about charging a car battery.

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Can You Charge A Car Battery With Two Chargers?

A Car battery with red and black battery Jumper Cables with copper clamps attached to the terminals. - Can You Charge A Car Battery With Two Chargers.

It is possible to charge a battery using two chargers. However, the chargers should support parallel operation to avoid damage. When using two battery chargers, always ensure they are of similar ratings in parallel. This increases the charging process.

Note that a battery charger carries both a constant voltage and current, so one charger has just one amp. Therefore, two batteries make up two amps with more voltage, meaning additional power is involved. 

Generally, the current the battery draws is based on the voltage difference and the internal resistance (IR). It is okay to use two chargers, especially if the single charger cannot offer the needed power.

For your car battery to last long, you need to smart charge it. Consider getting advanced chargers with parallel choices if you want to support the currents. 

To change a car battery with two chargers, you should connect the battery's three positive terminals and the chargers. After that, you can proceed with connecting the negative terminals. It is best if the chargers have similar output voltage. 

Effects Of Charging Car Battery With Two Chargers

Check and charg car battery with charger from home electricity. Person measures voltage. Voltmeter to check voltage level on car battery. Car battery maintenance

While it is possible to charge car batteries with two chargers, doing so has drawbacks. If the chargers do not support parallel operation, the chances are both chargers will go bad. They will destroy each other.

Also, many amperes of current flow in a battery charging circuit, so if you use two chargers, the battery and chargers will be ruined. This is because the current may not flow in the right direction.

Chargers are meant to work with a specific voltage or current; both need to be constant for hours, unlike phone batteries that charge in minutes. Furthermore, connecting a battery to two chargers is just like connecting both chargers and this can cause short-circuiting.

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Can You Start A Car While Charging The Battery?

It is not recommended to start a car while charging the battery. This is because the current in the charger is too low and cannot start the car. It is okay to start the car only if the battery is fully charged. However, you do want to risk damaging your car battery, so you have to consider some things.

When the battery is charged, you can try turning the engine on while the charger is still attached. Always be careful at this point to avoid any damage.

Note that the car may need some voltage from the charger. Attempting to start a car while charging the battery can also ruin the battery charger's fuse or the charger itself.

It is better to go for battery chargers that have jumpstart capability if you plan on starting your car immediately. This type of charger comes with a 12 V adapter and is more suited here than the smaller ones.

What Happens If You Leave A Car Battery Charge For Too Long?

If you allow a car battery to charge for too long, it will overcharge. This could cause the battery to die. The untimely death of the battery isn't the only effect of overcharging, so avoid this issue.

If your battery is overcharged, it can boil a mixture of sulfuric acid and distilled water. Also, the battery's cover is likely to get hot and may even swell or melt as a result.

Additionally, dangerous hydrogen may accumulate in the battery cells. When this happens, the battery cells' covers start to swell and come out of small holes. If hydrogen comes in contact with oxygen, there could be an explosion.

The battery will explode if any electrical spark ignites the gas. The explosion may end up sending lead shrapnel all over the place. This is one of the most harmful effects of leaving a battery charging for too long.

How Long Does It Take Car Battery To Charge?

Battery charger.

Generally, a car cannot use one amp in one hour, but this can be helpful in determining the minutes or hours needed to charge a battery. This is because most chargers are produced the same, making it easier to know how long it takes to charge a battery.

It may take approximately 48 hours to charge a completely dead battery with a 1-amp charger. But this is different if your charger is 2-amp. It will take about 24 hours when a 2-amp charger is used. For every amp the charger is rated, an amp is restored in the battery.

You should bear in mind that this may differ based on the battery used. If your battery contains bad cells and struggles to maintain a charge as a result of calcification, charging it will take more time. 

There are different types of batteries, so if yours has 2 volts, expect it to take longer time to charge than the one with 10 volts. Note that determining the volt of your battery does not mean you already know the amps remaining.

How Do I Know My Car Battery Is Full?

car battery

To check if your car battery is full, it is necessary to measure the voltage using a voltmeter. If you have a 12.6 or 12.7 voltage, then your battery is fully charged. But if you are getting 12.2, the battery isn't fully charged yet. 

Whenever you notice a voltage of 12, this means the battery is still dead. A voltage reading of less than 11 indicates that the battery is faulty. 

A battery that has just been charged should have a voltage of about 13.8 or more. However, it is recommended to leave the voltage to reach the resting point. A day or a few hours is okay for this. Alternatively, turn the light on for some time.

It is ideal for determining the density of the acid through the cells. But newly produced batteries are well sealed, and it isn't always easy to get to the cell. That's why a voltmeter is the best bet. If you can get to the cells and take off the covers, collect some of the acids and put it in a densitometer.

Can I Just Idle My Car To Charge The Battery?

Rechargeable battery with connected measuring instrument and green leaf. The concept of clean energy.

Generally, a battery voltage is anywhere from 2.4 V to 12.6 V if the engine is inactive. However, the alternator's armature tends to spin when the engine is active since it is merged to the crankshaft.

With this, the alternator starts getting a voltage ranging from 13.5 V to 14.5 V both during its active and inactive states. This voltage means that the battery is charging.

A voltage regulator in the alternator is responsible for regulating the voltage the alternator puts out. This is one of the reasons why alternators are crucial. They help in charging car battery when it is not in use.

It is important to note that the DC generators in cars manufactured before 1960 cannot charge a battery that is not in use. This is because they put out minimal voltage. This is one of the issues associated with older vehicles.

When the engine is started, the alternator provides the energy used to power the electrical components like computers, power windows, and lights. It also provides energy for starting the engine when you want to use the car again.

Furthermore, the alternator can do all this work because it gets power from burning gasoline. Therefore, for the alternator to function and provide energy for other electrical components, it needs gasoline.

To Wrap Up

A car battery can be charged with two chargers. However, it is recommended to use chargers that support parallel operation. Bear in mind that using two chargers has its effect, including short-circuiting and damaging both chargers.

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