How to install a second battery for car audio?

When your car’s battery could not hold the charge for the time being, you may find two reasons behind this malfunction. The first one is you may need to replace the original battery and the second one is you may need to enlarge the existing battery power.

Installing an extra/second/auxiliary battery to the care system often makes the user very confused about installing the second battery for car audio. How does it work? Does it safe?

However, let eradicate all the confusion, let dive into the details.

Why you need to install a second battery for car audio:

Suppose the Engine Off service of your car( like your car’s inverters, Coolers, Car Refrigerator, Aftermarket Radios, Car’s Lighting, Car’s DVD Players) drainage the energy from the main battery included inbuilt with your car. In that case, it may go to create an issue relating to your vehicle’s start-up. So, a second battery is the only solution to stop a problematic start-up of your car.

The second thing is, if you run a Heavy-Duty Electrical Device (e.g., Electrical Winch), it may pull almost 300 to 400-amp power form your car’s in-built battery, which in further again may disrupt the primary function of the battery. A second battery is an excellent solution if there is a chance to winching huge.

A high-performance audio system also pulls a massive power from the existing car battery, which is generally out of the car’s original battery. Besides this, if you want to operate this high-performance audio system when your vehicle is resting, you need a second battery to your car so that your primary battery doesn’t become too old or too tired.

Besides all of these, if you like to enjoy some special activities like Tailgating, Camping with your vehicle, you will need a second battery. This dual battery will supply additional power to run your Television, Radio, and Cooking Equipment, and so on.

Where can you install a second battery?

You can set a second battery under your car’s bonnet if there is any space remaining free for the battery. You can use a battery tray (like SCN is universally fit able for all). If the SCN battery tray not suitable at your car, you can go for another customizable tray. However, if there is limited space inside your car bonnet to install a second battery, use a battery box to keep the battery safely at your cargo.

Guidelines how to Install a Second Battery for Car Audio System

Here we go with the step to step installation procedure of a second battery to the car.

  1. At first, take your car in the parking lot. Then turn off your car’s Engine. Let the Engine be cool for a while.
  2. Open the hood and disconnect the main battery. Use a suitable wrench to disconnect the Negative Terminal Connection. Finally, open the trunk.
  3. Determine the place where you want to set the battery. You can first give your priority ‘beside the Amplifier’ to set the auxiliary battery. The second place where you can set the battery is the Car Trunk.
  4. Once you have decided on the battery placement, keep the battery on that place.
  5. Use a battery box. Go for the drilling option to make some holes on the installing tabs on your straight on the floor trunk. Use bolt on the holes (you just created a while ago) and adequately tighten all of the bolts using a wrench. You can get all the hardware from the battery box.
  6. Once you have done the setting process, you have to wire your second or auxiliary battery correctly. However, firstly connect the positive side.
  7. To wiring, the second battery, use some copper wire with a heavy gauge. Use a Wire Stripper; remove some plastic cover from the copper wire to make a terminal end on both sides of the copper wire.
  8. Add one side of this positive terminal (copper wire) to the Positive Terminal of the battery and the other terminal to the Amplifier’s Lug.
  9. Finally, tight the screws as firmly as possible. Uses a wrench to accomplish this tighten procedure.
  10. Find the ground wire from your auxiliary battery’s negative side. Once you have connected properly, both the negative and positive terminal closes your car’s trunk/hood. Make sure you have connected both the negative terminal on the ground and the positive terminal together. (Using an In-line fuse/Battery Isolator for this connections)

Safety and precaution:

  1. Be careful; you are installing your second battery with the thickest gauge you reasonably could use.
  2. You cannot neglect the fact; all batteries have a chance for an explosion. Therefore, install the battery as in a Solid Speaker Box, or at your Engine Compartment or in the trunk. However, set the second battery as near as to your car amplifier


What are the benefits of using a second battery to the car system?

First of all, a second battery will expand your car’s primary battery’s lifespan. It will reduce the load from the main battery. Secondly, without thinking about the main battery getting down, you will enjoy some engine-off services. Like AC, Radio, and Refrigerator will run on, etc.

Does a second battery can back up my original battery?

Yes, it can. If your main battery is worn out suddenly, your second battery will back up the original battery you just had in your car. So without losing any extra money or time, you are going to enjoy your expecting car service.

Is it is safe to use a second battery in my car?

It is safe, if you properly install it. It is secure if you are correctly wiring all the negative and positive connections.

Final verdict:

If you are running many other electronic tools, your main battery drained out a lot; only, in that case, your second battery could be a great end off. Otherwise, if the main battery cannot hold the charge without any power drainage issues, an additional battery could do nothing in that case. So find precisely why you need the second battery and then go for installing it.

That is all about How to install a second battery for car audio. If you feel good to read this article, please share this article.

Thank you.

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