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Manual Vs Automatic Car Battery Charger: Pros, Cons, & Differences

Are you looking for a new charger for your car battery? Don't worry, this article will help you make an informed choice. We've researched the two battery charger types - manual and automatic and we're glad to share with you what we've learned.

An automatic car battery charger monitors the battery level as it charges it. You won't have to worry about overcharging and damaging your battery. You have to monitor the charging with a manual charger. Once the battery is fully charged, you must disconnect the charger from the battery, or else, your battery will be damaged due to overcharging. It can be used on a dead battery and will allow you to perform an equalizing charge to recondition a sulfated battery.

Keep on reading to learn more about these two types of car battery chargers - how they are different and their respective advantages and disadvantages. We'll also give you tips on how to choose the perfect charger for you. Let's begin!

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battery charger car auto repair shop manual type, Manual Vs Automatic Car Battery Charger: Pros, Cons, & Differences

Car Battery Charger: Which is Right For You

The car battery isn't just used for starting your vehicle. It is also running even when your car is parked. It powers your vehicle's sensors, security system, lights, or stereo when the engine is off. 

The battery turns chemical energy into electricity to be able to do all these. The alternator recharges the battery while your vehicle is in use but only when there's extra power that's not being used up by your car's electronics.

There are times when the alternator can't supply all the power that your car needs while it's running especially when many electrical devices are simultaneously in use. When this happens, your car uses up power from the battery and it loses some of its charge. Aside from usage, extreme temperatures can also deplete your battery's charge.

That's why it is recommended that you still use an external car battery charger to bring it back to full capacity so that your vehicle's performance won't be affected. You connect the charger's cables to your battery's terminals then plug in the charger to a power source and it'll start charging. 

But of course, you have to use a charger that's compatible with your car battery. Check your vehicle's battery type if it's a wet cell, gel cell, absorbed glass mat (AGM), or lithium-ion then look for a car battery charger that'll work well with it.

And when you're shopping for a car battery charger, there are basically two types that you'll find in the market - the automatic or smart charger or the manual car battery charger. We'll discuss both in detail so you can choose which one is right for you.

man inspection holding battery capacity tester

Differences Between Automatic and Manual Car Battery Chargers

A manual car battery charger pushes current to your battery and will continue doing so as long as it is connected to it. You have to disconnect the charger or unplug it from its power source to stop charging. Otherwise, your car battery will be overcharged and permanently damaged.

Check out this manual car battery charger on Amazon.

There are different tools that you can use so you can monitor the battery charging level. You can use an ammeter and it'll let you know the ampere value. The needle on the window indicates the charging percentage. Once it reaches the green side, it has completed charging. Meanwhile, the voltmeter tells you the voltage. You will know that charging is complete when it reaches 12.6 volts or a little higher than that.

Click this link to find this voltmeter/multimeter on Amazon.

On the other hand, automatic car battery chargers have a built-in capacity to monitor the battery level by themselves. This means you can basically leave it connected to your vehicle's battery and you don't have to worry about overcharging.

Find this automatic car battery charger on Amazon.

Let us go through the benefits and drawbacks of using automatic and manual car batteries to know more about their differences.

What are the advantages of an automatic car battery charger?

hands charging car battery electricity using alligator clips

An automatic car battery charger is referred to as an intelligent multi-stage charger. It has the ability to monitor the battery and will only begin charging when needed. It'll also turn off automatically once the battery is fully charged, that's why you can be confident that your battery won't be overcharged even if you leave the charger connected to the battery for a long time.

Overcharging a car battery is bad for its health and can do irreparable damage to the unit.

This type of car battery charger is good for battery maintenance, especially those that you put in storage or that you don't use often. With its ability to charge your battery when needed, it will prevent depletion of charge and sulfation. This is the condition wherein lead sulfate builds up on the battery's surface when it is discharged for a long time. This makes batteries more difficult to charge and can render them unusable.

What are the disadvantages of an automatic car battery charger?

You cannot use this charger type for batteries that are dead or those registering zero voltage. It is also not possible to perform an equalizing charge to recondition the battery once sulfation happens.

Most of the time, automatic car battery chargers are also more expensive than manual chargers. But this is because they also come with other features that enhance their performance and make them more useful for your battery repair and maintenance needs.

What are the advantages of a manual car battery charger?

You will see different settings in a manual car battery charger that allow you to choose the most efficient way of charging your particular car battery type. You can use it for deep cycle batteries, flooded, or AGM. Many manual car batteries also have options for voltage and amperage.

In other words, these chargers are versatile and can be used not just with your car battery but for other batteries as well.

A manual charger allows you to perform an equalizing charge to your battery so that you can recondition it to a usable state. This is helpful when sulfation happens. It overcharges your battery or applies a higher voltage but in a controlled way.  It will restart the battery's charging cycle so that your battery's condition will be back to normal. 

It also allows you to charge even a dead battery. This isn't possible when using automatic chargers. Manual chargers are also more affordable than automatic chargers.

What are the disadvantages of a manual car battery charger?

When using a manual car battery charger, you have to be mindful of the time needed to charge your battery. It doesn't have the ability to analyze your battery's condition.

You have to disconnect or unplug it once the battery is already fully charged. If you don't, you might end up damaging the unit. Since it doesn't shut off by itself, it'll continue to add amperage or voltage to your battery even by small amounts. This isn't good for your battery's health.

This charger type cannot be used for battery maintenance or those batteries that you have to put in storage because you won't use them for more than two weeks. 

We've enumerated the pros and cons of manual and automatic car battery chargers. In doing so, you've learned more about how they are different from each other when it comes to usage and function.

Factors to Consider When Buying a Car Battery Charger

close hand charging car battery electricity

In highlighting the differences between an automatic and a manual car battery charger, we don't aim to tell you which one is better than the other. Rather, we want you to look at what each charger offers to see if it suits your particular needs.

Here are the important things you need to think about before making a purchase.

  • Compatibility. We have to reiterate this point. It doesn't matter if the charger type comes with many advanced features. If it's not compatible with your car battery, it won't work. 
  • Durability. Go with trusted brands, check the warranty, and read customer reviews to give you an idea regarding the durability of the product. Find out their experiences with the unit itself and the attachments that come with it. For example, there are clamps that are too small in size which makes them difficult to attach to the battery and break easily.
  • Ease of Use. Look for a car battery charger that comes with an easy-to-understand instruction manual and has included parts that'll make it easier to connect the charger to the battery and power source. Oftentimes, large clamps, longer cables, power cords, and a friendly interface do the trick.
  • Added Features. You'll see chargers with an LCD screen, temperature sensor, overcharge mode, and other battery repair features. Check which feature matters most to you depending on your needs. Do you need a maintainer or a desulfator? Do you need to charge a completely dead car battery? Do you have other vehicles with different battery types? See which charger fits your needs.
  • Cost. As mentioned earlier, manual chargers are more affordable. Automatic car battery chargers are expected to be more expensive since most also come with added features that increase their functionality. Consider which purchase will give you the most value for your money.
  • Other Considerations. For some users, the size and weight matter especially when we're talking about portability. Other users prioritize charging speed. It may take between 10 and 24 hours to completely charge a battery. Of course, the faster it charges, the better.

At the end of the day, it is not necessarily about manual versus automatic car battery chargers. It is about which charger type best suits your needs and preferences.

Final Thoughts

battery charger car auto repair shop manual type

The main difference between manual and automatic car battery chargers is the monitoring required. You must monitor a manual charger while you can basically connect and leave an automatic charger. Nowadays, you'll find automatic chargers that can also do what manual chargers offer. Choosing between the two types boils down to your budget and particular battery maintenance or repair needs.

To learn more about car battery chargers, you may read the following posts:

Can I Use An Extension Cord With A Car Battery Charger?

Why Is My Car Battery Charger Draining My Battery?