How to Charge a Cordless Drill Battery without a Charger


Last Updated on January 31, 2023 by John Patterson

Cordless drills are considered bliss among users. Because of their portability and other exciting features, they have become the sweet child of the drills.

However, it’s common among people to break the charger or ruin it somehow. After ruining the battery charger, people tend to buy a new one.

However, there’s another way of charging without buying a charger.

At this point, you must be thinking- How to charge a cordless drill battery without a charger?

Well, it’s simple: you have to charge it via other batteries or make a battery charger of your own.

So, let’s take a look at charging a cordless drill battery without charger details without wasting any more time-

How to Charge a Cordless Drill Battery Without a Charger

Method 1: Charging with Batteries

charging a drill battery

We’re guessing that you already understood the basic principle of this method from the headline.

So, let’s dig into charging a cordless drill battery without a charger process-

Necessary Items

way to charge a drill battery

Before charging up your cordless drill battery without a charger, you must gather some items. It’s hard to explain these items through a listicle. So, we’ll explain these, Para by Para.

The first thing you need is connectors. Make sure you have electrical connections with which you’ll connect your batteries. These connectors can be pieces of wires too. But you have to ensure that these stick to the ends of the batteries.

Next, you have to gather up some batteries. But do you know how many batteries you’ll need? Well, the answer to that question depends upon your drill battery voltage.

To determine the battery number, you have to do some calculations. We’ll explain the whole calculation through an example-

Let’s say your cordless drill battery is 18 V. And you’ve found 1.5 V batteries in the market. Now, let’s calculate how many of these small ones are required-

18 V/ 1.5 V = 12 batteries

Gather up these items with some extra stuff like pliers, tape, etc.

Assembling Batteries

Do you know what a series connection is?

A series connection is a closed circuit or connection in which the current flows in one direction. Think of it like a looped road where all the cars go through the same path.

Why are we learning this?

Well, that’s because you have to create a series of connections.

Don’t panic. We’re here to lay out the way. So, let’s look at the steps-

  • Find out the positive and negative sides of each battery.
  • Take two small batteries and connect the positive side of one with the negative side of another through the connecting wires.
  • Use your electric tape to secure the connectors in place.
  • Do the same with all the 12 small batteries (continuing from the example)
  • Bend the connected batteries in a U shape.
  • Connect the series connection’s positive side to the drill battery’s positive side.
  • Connect the series connection’s negative side to the drill battery’s negative side.

Keep the whole thing for around 2 hours or so. Your batteries will get charged pretty quickly.

However, keep close to your charging station. If you smell something funny, then disconnect everything.

Method 2: Making a Charger

making a cordless drill battery charger

If you think the first method isn’t for you, we have devised another way.

However, this method needs a lot of calculation and physical work.

You have to cut down wood for this method. Moreover, you have to do some intricate electric work.

You have to create a step-down transformer. Now, what is that?

This transforms high voltage AC into low voltage high Amp DC.

If you want to dig into this super complex process, there are several online tutorials. You’ll understand the whole process through 2 or 3 tutorials.

We discussed this method fully here. But later on, we understood that it’s tough to make someone understand through writing.

However, even after the video tutorials, we recommend you take help from someone adept in electrical engineering.

That’s because this method has risks too.

If you make mistakes in selecting components, you might face grave consequences. Starting small fire fires is pretty standard in this case. If your luck goes south, you could have your whole house burnt down.

So, keeping a fire extinguisher beside you while doing this is better.

However, we again suggest you try out the first method. Moreover, considering costs, buying a new charger is far cheaper than any of these methods.

Safety Measures

No matter how secure the technique is, you should never leave the site of your work, primarily if they work in electrical.

So, use plastic sandals while working with these batteries and transformers.

Frequently Asked Questions

Question #1: How do you charge a lithium-ion battery (li-ion) without a charger?

Answer: By using pc and USB cables. These cables have a built-in charge wire. This wire supplies 5 volts from your computer and a current of 100mA to 500mA. So, you can cut up the cable and bring out the charge wire. Your battery will start charging once you connect it to the pc.

Question #2: Can I charge an 18V battery with a 24V charger?

Answer: Technically, yes. But there is no guarantee that you’ll be able to charge it fully.

Question #3. What are the best drill brands?

Answer: There are a few top-quality brands available on the market. Read the latest honest and unbiased review of Dewalt and Ryobi Drills.

Final Verdict

We have been through much on charging a cordless drill battery without a charger. We can say that here we have covered 2-3 classes of an electrical engineering course.

But ultimately, none of these solutions are feasible. You can use them only if you have no other way left.

Good luck. Happy charging!

Related Reading:

#1. Using a cordless drill like a pro
#2. Best Cordless Drill Brands
#3. Step-by-step guide to cordless drill storage
#4. Step-by-step guide to winterizing a pressure washer.

Leave a Comment