Have you ever wanted to really crank up the volume in your car, but found the music starts distorting or the lights dim whenever the bass hits? It’s frustrating when you can’t enjoy your expensive sound system to its full potential.
The problem is your stock electrical system and battery simply can’t provide enough steady power for today’s high-powered amps and subwoofers. But don’t worry, you can fix this by installing a second battery dedicated to your car audio system.
In this guide, I’ll walk you through everything you need to know to safely add that second battery. With some simple tools and basic mechanical skills, you’ll have your system pounding out the jams at full volume in no time. Let’s get started!
Why Add A Second Battery?
Before we jump into the installation, you might be wondering why add a second battery in the first place?
Well, there are several excellent reasons:
- More power for your amps. Today’s amps can draw over 100 watts of power. Your stock battery alone can’t deliver enough stable current for long.
- Play louder and longer. With the extra juice, you can really crank the volume when parked and listening to tunes. A second battery provides hours of playback time, not just minutes.
- Prevent electrical issues. Ever see your headlights dim for a second when your subs hit hard? That’s strain on the system. A second battery prevents this and other issues.
- Improve sound quality. Inconsistent power leads to distortion. The second battery provides a steady voltage for cleaner audio output.
So in short – more power, longer playtime, prevent electrical gremlins, and improved sound. That’s what a second battery brings to the table!
Choosing The Right Second Battery
When selecting a secondary battery, there are several important factors to consider:
You’ll want the second battery to be the same type as your current battery. For most modern vehicles, that’s a lead-acid battery. Using the same battery chemistry avoids compatibility issues.
Look for a battery with greater reserve capacity and cranking amps than your stock unit. More capacity means more power for your system. Aim for at least 20-30% higher ratings.
Make sure the battery will physically fit the space you have available. Measure twice to ensure it fits before purchasing.
Brand and Age
For best performance, use two new matching batteries from the same manufacturer, ideally purchased at the same time. This prevents an imbalance.
Avoid using an old weak battery for your secondary. Check that it can still hold a proper charge and voltage first.
Install the battery close to your amps to minimize power loss over the wiring distance. The trunk is ideal.
Follow this criteria, and you’ll have a top-notch second battery ready to install!
How To Wire The Batteries
Once you’ve got your new battery, how do you wire it up? You’ve got two options:
In a series connection, the batteries connect end-to-end, with the positive from one to the negative of the next. This provides additive voltage but identical capacity. Rarely ideal for audio applications.
For car audio, you’ll usually want to wire your batteries in parallel. This means connecting the positive terminals to each other, and likewise with the negative terminals.
Parallel wiring combines the capacities of each battery for more total power. It also evens out the workload so one battery doesn’t get over-stressed. Just what you need for your amps!
Step-By-Step Installation Guide
You’ve got your new high-capacity battery and know how to wire it. Now let’s get into the nitty gritty of the install process! I’ll cover this in six key steps:
Step 1 – Select The Install Location
Find a good spot to mount your second battery. The trunk or rear cargo area usually works well. If installing up front, use a sealed battery box for safety.
Step 2 – Disconnect The Existing Battery
Always disconnect your current battery first! This prevents dangerous sparks during installation.
Step 3 – Mount The Second Battery
Securely mount the second battery in place using the appropriate tray or hold-down. Ensure it won’t shake loose.
Step 4 – Connect The Positive Cables
Run a cable from the + terminal on each battery and connect them. Add an ANL fuse within 18″ of the batteries.
Step 5 – Connect The Negative Cables
Likewise, connect the two negative terminals to each other. No fuse is needed for the ground connection.
Step 6 – Connect The Ground Cables
Finally, attach a ground cable from each battery to a metal chassis grounding point.
Once wired, keep the batteries close together so the cables aren’t stretched. Now you can connect your amps to the new battery and get rockin’!
To squeeze every last bit of power from your new dual-battery setup, keep these bonus tips in mind:
- Use thick 0/1 gauge power cable to minimize voltage drop.
- Add a battery isolator to disconnect both batteries when not in use.
- Adjust alternator charging output to suit your total capacity.
- Don’t discharge batteries below 50% to prolong their lifespan.
- Check voltages periodically to catch any impending issues early.
Despite best efforts, problems can occasionally crop up when running dual batteries. Here are some common issues and potential solutions:
- Dimming lights or weak power: Battery is under-charged. Check connections are clean and tight.
- Premature battery failure: Over-discharging battery. Do not drain below 50% capacity.
- Noisy audio: Loose battery or bad ground connection. Inspect all cables and connections.
Most dual battery problems can be prevented by proper installation and maintenance. But if issues arise, systematically check each part of the system to isolate the culprit.
Adding a second battery is one of the best ways to get the absolute most out of your car audio system. The extra capacity prevents strain on your car’s electrical system while providing consistent, noise-free power.
While the installation requires some effort, the work is absolutely worth it. With a robust dual-battery setup powering your amplifiers, you’ll finally be able to crank up the volume and feel that bass without distortion or dimming lights.
So don’t settle for lackluster performance from your expensive audio gear. Follow this guide and install that second battery for the ultimate listening experience!