12v vs 18v Battery | What’s the Difference?

If you are looking for a new battery for one of your tools, you may be wondering what the difference between 12v and 18v options are. Obviously, one is a higher voltage than the other, but what does that mean in practice and which is better for your needs? This article will take you through all of the main differences and help you decide which one you should buy.

What’s the Difference Between a 12v and an 18v Battery?

Most people assume that an 18v battery gives you more power than a 12v battery, but it isn’t actually that simple. You can get the same power from various voltages, depending on the current that the appliance draws. A higher voltage means that the electricity is distributed more evenly. In practice, this often means that the tool or appliance is more powerful, but higher voltage doesn’t guarantee more power.

There are also physical differences between the two batteries. An 18v battery is quite a bit larger than a 12v battery, which is a potential issue for people that are using tools for long periods or in tight spaces.

In short, an 18v battery is (usually) more powerful but a 12v battery is smaller and easier to handle.

Can You Use a 12v Battery on an 18v Tool?


Depending on the type of drill you have, the batteries from a 12v drill may fit in an 18v tool. However, that tool is designed to run on 18v, so when you put a smaller battery in, you won’t get the same power output and the tool won’t function properly. In some cases, using incompatible batteries could damage the tool, so it’s best to use the recommended battery size.

DEWALT DCB126 12V MAX* 5.0Ah Lithium Ion Battery

Can You Use an 18v Battery on a 12v Tool?

Technically, you can use an 18v battery on a 12v tool but it is not advisable. An 18v tool gives out a lot more power than a 12v tool, and the tool isn’t designed to handle it. The extra power will quickly burn out the motor and damage your tool. It could be very dangerous and you’ll break your tool in the process so, again, stick to the recommended batteries.

Will a 12v or an 18v Tool Have More Power?

An 18v battery has roughly twice the power that a 12v battery does. However, the relative power of the tools can vary a little. Because the voltage doesn’t necessarily translate to power in every case, a good 12v tool can kick out as much power as an old 18v one. The technology is improving a lot and 12v tools are more powerful than ever.

But the same is true of 18v tools, so if you’re comparing two new tools, the 18v will still have more power. That said, you don’t necessarily need an 18v tool and a 12v one may be adequate, depending on the job.

Does an 18v or 12v Battery Take Longer to Charge?

In a direct comparison, a 12v battery charges quite a bit faster than an 18v battery, which is a big bonus for many people. However, there are fast chargers available and these are often made for 18v chargers because charge times are more of a problem with these. So, if you are willing to invest in a good fast charger, there isn’t much difference. Otherwise, 12v batteries charge much quicker.

Will an 18v or a 12v Battery Drain Faster?

Although an 18v battery is bigger and heavier, it is often worth the extra weight because it runs for a lot longer. If you were to do the same job with an 18v and 12v tool, you would get a lot more run time before you needed to charge the battery. This is especially true for more power intensive tasks because the larger battery can handle it better and the tool doesn’t have to work as hard, so the battery won’t drain as fast.

Can You Charge an 18v Battery with a 12v Charger?

Technically, you can charge an 18v battery with a 12v charger and the first few times you do it, it will work ok. The battery will charge and you can go on using your tools as normal. But over time, you will start to notice that the battery doesn’t charge properly and it doesn’t hold its charge for as long. Eventually, it will stop working altogether, so it’s best to avoid charging with a lower voltage charger.

Can You Charge a 12v Battery with an 18v Charger?

Charging a battery with a lower voltage charger can ruin it over time, but it’s even worse if you charge a 12v battery with an 18v charger. The battery is not designed to take that much power so it can easily overheat and do a lot of damage to the battery.

There is, however, one big exception to this rule. Some tool manufacturers make batteries and tools that are interchangeable and have universal chargers that can charge both. Makita, for example, makes a great interchangeable charger. But it only works on their newer models and if you have old batteries, it’s not advisable to use the wrong type of charger. So, double check the manufacturer’s guidelines about charging and stick to them to be safe.

Which Batteries are More Affordable Between 18v and 12v?

When you compare the price of 18v and 12v batteries, the larger batteries tend to be more expensive, as you’d expect. However, the price difference is not proportionate to the difference in power. Take these 18v dewalt batteries and 12v dewalt batteries, for example. The 18v battery gives you roughly twice the power of the 12v one, but it is nowhere near twice the price. So, if you are looking for value in terms of money spent for the power you get, 18v batteries are great.

DEWALT 18V Battery, XRP, Combo Pack (DC9096-2)

Are 18v Batteries Heavier in Weight than a 12v Battery?

Yes, 18v batteries are bigger and heavier than 12v batteries, in most cases. This is something you really need to think about when using them on handheld tools like drills. If you’re working all day long with it, do you want a big heavy battery or would something lighter be more suitable?

Can You Buy a 12v and 18v Adapter Kit?

A lot of tool manufacturers are now making universal batteries that fit with all of their tools, and many of these allow you to use the batteries interchangeably. However, you cannot easily use adapters like you can with larger batteries. You can find adapters that will allow you to charge the batteries with one power source, but not an adapter for the drill.

What’s the Difference Between a 12v and 18v Drill?

Power is the main difference between a 12v drill and an 18v drill. The 18v drill gives you more torque, so if you’re driving into tough materials, the drill handles it better. It also gives you a longer run time, so if you need to work all day long without charging, it’s more reliable. On the other hand, a 12v drill is smaller and more lightweight.

The Verdict – Which Should I Choose?

Overall, an 18v battery performs better. They give you more power and they last longer without being charged. They’re also more cost-effective in terms of the amount of power you get for the price you pay. But the main downside is the size and the weight, which is a problem in some situations. If you are working in a tight space or you don’t want to hold a weighty drill all day, you might want to go for a 12v battery instead.

Read our related battery article: