How to Charge a Cordless Drill Battery Without a Charger
Your drill runs out of juice, it is annoying, but not the end of the world. You whip out your charger; stick the battery in and the charging begins. Except it does not charge. You play around with the charger for a little bit and try to get it to work. It has saved you countless times over the years but those days are gone. Your charger has finally died. Now you have another problem.
Buying a new charger costs a lot of money. Money which you do not have to spend. Perhaps your drill was old and you cannot even buy a new charger for it. Your problem now is that you have a dead battery and no way to charge it. Or do you?
A Battery Needs a Battery
There is another way! But before we begin let’s start by saying that power has to come from somewhere. To charge a battery you need a power source. For us this means using a battery to charge a battery. This may sound like a weird thing to do; redundant almost but there are ways around the redundancy. You can hook your battery up to main power; but there are so many dangers which come along with that, and it is simply not worth it. Take it from us use a battery and not main power.
So what happens when your second batteries die? Should you go out and buy a lifetime supply? Well your drill battery was rechargeable, so why shouldn’t the batteries which are now going to power that one? It may seem like you are taking a long way around, but if you want to keep using your drill, then it is a great way to do so.
Charging From a Battery
The first thing to do is to check your battery. You need to make sure that you have connectors which your new battery is going to be connected to. The next thing to do is to make sure that you have your batteries from which you are going to draw your charge and make sure that they are charged.
Then, check the voltage of your drill battery. You need to ensure that you have enough batteries to charge your drill battery to the correct voltage (erring on the side of caution and going below is recommended). Once you know the voltage, you need to assemble enough batteries to give you that voltage. For example, if your drill battery is 12V, then you will need 8 x AA batteries (1.5V) connected in series. This will give you 8 x 1.5V = 12V. You also need two pieces of wire to connect the new batteries to your drill battery.
Assembling the Batteries
The batteries need to be connected in series. In the above example, we are using 8 AA batteries to charge one 12V battery. Have your 8 batteries ready, along with the two wires and some electronic tape. There is one thing you need to keep in mind when you are connecting the AA batteries – they should be connected positive to negative, but when connecting to the drill battery, they should be connected positive to positive and negative to negative.
Take the first two batteries and place the positive end to the negative end of the other battery. Use the tape to connect the two batteries together by holding them so that they connect and then wrapping the tape around the two batteries to hold them in place. If there is a gap between these two batteries (or any of the others), then the system will not work. Continue to add batteries to the first two, wrapping them with tape each time, until you have a length of 8 batteries.
Next, you need to attach the wires. Find wires with plastic covering and expose both ends on each wire. This will allow you to manipulate the wire without getting hurt (you are under no real threat, but the wires can get hot). Attach a wire to the positive side of your long battery (the end with the positive end of a battery exposed) and one to the negative side (the end with the negative side exposed).
Bringing it all Together
Once you have all of your batteries connected and the wires in place, you can attach the long battery to your drill battery. This is where you need to make sure that you are connecting the positive side to the positive connections and the negative to the negative. Be sure to check for both of these terminals on your drill battery before you connect the wires.
You can hold the wires onto the connectors of your drill battery, or you can tape them there, but you should always be there in case something goes wrong. If you detect any weird smells, then take the battery outside and disconnect it. If anything seems out of the ordinary, then disconnect the battery. The charging will take some time, but if the long battery has the same or less voltage than the drill battery, then you will never overcharge the drill battery.
When you are done, disconnect the batteries and recharge them, ready for next time.
Here is a short video on how to charge a cordless drill battery without a charger in a pinch:
If you are a bit of a handyman and like to fix things around the home, then you know how important it is to have a drill which works. Having a cordless drill is a lot more convenient than one with a cord, but there is the problem of having to recharge the battery, and after some time, the charger will give up the ghost and cease to work.
When this happens, it can be hard or expensive to find a replacement charger. The great news is that there is another way. As you have seen in our step-by-step guide, you can charge your battery without a charger. Take precautions and follow the guide exactly. Your safety should be your No. 1 priority.