How To Extend Car Battery Cables?

Have you ever wanted to know how to extend car battery cables, because wear out before the rest of the car does? You don’t have to let them! Follow these quick and easy steps to extend your cables, save yourself some money, and have a more reliable vehicle in general.

How To Extend Car Battery Cables?

Below are the 7 tips for you

1. Get The Right Tool

You’ll need a Phillips head screwdriver, an adjustable wrench, and wire cutters. Plus, you’ll need some cable-extending equipment. You can find this at any hardware store. Make sure it matches the size of the extension cord you’re using. Now, follow these steps:
Now it’s time to start cutting! Measure how much extra length you want to add to each end of the cable, and then use the wire cutters to cut off that amount from each end of the cable.

Then unscrew the cap on one end of the extension cord, so there is about four inches worth of slack before tightening it back up again (and don’t forget to remove those insulating sleeves!). Use the Phillips head screwdriver to remove all three screws holding together one side of the connector on both ends of your new extension cable.

2. Cut Both Old And New Cables.

You’ll need to cut the old and new wires by extending your car’s battery cables. First, use a sharp knife to cut through the insulation around the wire.

Then, use a pair of pliers to twist the wire until it breaks. Repeat this process for both the old and new cables.

3. Clean Up The Terminals And Cable Ends

  • Start by disconnecting the battery’s negative (-) terminal.
  • Once the negative terminal is disconnected, clean up any corrosion built on it with a wire brush.
  • Disconnect the positive (+) terminal from the battery.
  • Again, use a wire brush to clean up any corrosion that has built up on the positive terminal.
  • Once both terminals are clean, you can begin extending the battery cables.
  • To do this, splice an additional cable length between the existing cable and the terminal.
  • Reconnect both terminals to the battery and test your extended cables!

4. Solder The Two Sections Together

Soldering is the way to go if you’re looking How To Extend Car Battery Cables. Here’s a step-by-step guide

  • Get a soldering iron and some solder wire
  • Cut the cables in half with wire cutters (if necessary)
  • Clean up any frayed or loose wires with sandpaper
  • Strip each cable end by making 1/2 inch cuts on each side of the copper conductor with wire strippers
  • Remove the insulation from one cable using pliers and expose at least 1/2 inch worth of copper conductor.
  • Then wrap it around the other cable’s exposed copper conductors until they meet.

5. Heat Shrink (Optional)

  • Get some heat shrink. You can find this at most hardware stores.
  • Cut the heat shrink to size. Make sure it is long enough to cover the entire length of the exposed wires.
  • Slide the heat shrink over the wires.
  • Use a heat gun or lighter to shrink the heat down over the wires carefully. Be careful not to melt the wires!
  • Once the heat shrink is in place, test the connection by starting your car. If everything works, you’re all set!
  • If you have any questions, feel free to ask a mechanic or refer to your car’s owner’s manual.
  • With proper care and maintenance, your car’s battery cables should last many years!

6. Please Remove The Battery From The Vehicle And Reconnect It.

First, you’ll want to remove the battery from your vehicle. Then, you’ll want to disconnect the negative and positive terminals first. Once the terminals are divorced, you can begin extending the cables.

You’ll want to add about two feet of length to each cable. Once you have extended the wires, you can reconnect the positive terminal first and then the negative terminal. Finally, you’ll want to reinstall the battery in your vehicle.

7. Test New Cable Before You Start Driving

Before you start driving with your new, extended battery cables, testing them out is essential. Doing so will help you avoid any potential problems down the road. To test your new wires:
Ensure they’re correctly connected to your car’s battery.
Turn on the ignition and let the engine run for a few minutes.

Turn on your car’s lights, including the headlights, taillights, and interior lights.
Honk the horn to make sure it’s working. If everything looks and sounds good, then you’re good to go!

Can You Join A Battery Cable?

If you’re looking to give your car’s battery a longer lifespan, one option is to extend the cables. This can be done by joining two sets of positive and negative wires together with solder and heat shrink tubing.

You’ll need to clean the contact points, apply flux, and join the wires before soldering. Once the joint is cooled, you can use heat shrink tubing over it for extra protection. Remember that this method will only work if the wire gauge and amperage are the same.

Can You Splice Battery Cables Together?

You can splice battery cables together with the proper tools and techniques. Doing so can give you a longer-lasting battery cable.

However, you must not damage the insulation on the wires or create any electrical hazards. Follow these steps if you want to know how to extend car battery cables together.

Can You Extend Battery Charger Leads?

You can extend your car’s battery cables if you feel the need! All you’ll need is some additional cable, solder, and heat shrink tubing.

Remember, extending the leads will also increase the resistance, so it’s not recommended if you’re planning on running high-powered electronics off of them. If you take these precautions into account, extending your car’s battery cables can give you many more years of use!

How Can I Make My Car Battery Terminal Bigger?

There are a few ways you can make your car battery terminal bigger. You can use terminal adapters available at most auto parts stores. You can also use heavy-duty cable lugs, providing a more secure connection.

Finally, you can solder the connection to make it even stronger. If you do any of these things, wrap the exposed metal in electrical tape to prevent corrosion.

How Do I Connect Two Battery Cables?

To connect two battery cables, you’ll need to:

  1. Clean the ends of the cables with a wire brush. This will help ensure good contact between the cable and the battery terminal.
  2. Place one end of each cable on the ground. This will help prevent sparks from flying when you connect the wires.
  3. Connect the positive (red) cable to the battery’s positive terminal, and then connect the negative (black) cable to the negative terminal of the battery. Ensure the clamps are tight so they don’t come loose while driving.
  4. Start your car and let it run for a few minutes to charge the battery.

How Do You Connect Battery Cables?

Assuming you have the proper tools and materials, About lengthening the car battery cable is a relatively simple process. You’ll need to connect the positive cable first, followed by the opposing line.

Once both are connected, you can test the connection by starting your car. If everything goes smoothly, you should be good to go!


Although you know how to extend car battery cables with standard jumper cables, you may be in a situation where you need to extend them.

Whether you’re trying to jump-start another vehicle or want to keep your car’s battery going for a more extended period, you can do a few things to extend the life of your battery cables.