How to Run Lithium Batteries for Car Audio?
If you’re looking to upgrade your car sound system, a DIY lithium car audio battery may be the way to go.
Lithium batteries are more powerful and efficient than traditional lead-acid batteries, and they can be a great way to power high-end car audio systems.
To run lithium batteries for car audio, follow these steps:
- Charge the battery using a dedicated lithium battery charger.
- Mount the battery in the back of your car using battery brackets and bolts.
- Connect the positive and negative terminals of the battery to the charge controller using battery cables.
- Connect the charge controller to the car alternator.
- Run the amp by connecting the positive and negative terminals of the amp to the positive and negative terminals of the battery.
In this blog post, we’ll show you the complete process of how to install and run a lithium car audio battery.
Why Lithium Batteries for Car Audio?
Lithium-ion batteries are becoming increasingly popular in the scope of car audio, and for good reasons.
Here are the benefits you’ll see running lithium batteries for car audio:
- They’re much lighter. This is a big advantage if you’re trying to reduce clutter and free up some space in your vehicle.
- They don’t require as much maintenance. Lead-acid batteries need to be regularly topped up with water, whereas lithium-ion batteries can go for months or even years without requiring any maintenance.
- They can be quickly recharged,and their amperage stays on the higher side. This means you won’t have to worry about your music sounding faint or distorted.
- The resistance of lithium car audio batteries stays low and the voltage stays close to that of factory car audio batteries. This is important for ensuring that your car music will sound louder and clearer.
- They’re more environmentally friendly. Lead-acid batteries contain toxic chemicals that can be harmful to the environment, whereas lithium-ion batteries are much cleaner and safer.
Overall, lithium car audio batteries offer a number of advantages over traditional lead-acid batteries, making them the perfect choice for powering your car audio system.
However, lithium batteries are more expensive than AGM batteries. And if you’re using them with your standard car alternator, they’ll not perform optimally.
DIY Lithium Car Audio Battery Connection Process
Here’s the complete DIY process to run lithium batteries for car audio:
Charge the Battery
Car audio lithium batteries are transported at a 30% charge for safety purposes.
So, the first thing to do when you first get your battery is to charge it with a lithium battery charger before hooking it up to your custom car alternator.
When you buy a lithium car audio battery, you’ll get a charging unit for it.
Mount And Secure the Battery
- Position the lithium battery in the desired location at the back of your car.
- Using the appropriate size drill bit, drill four holes into the car’s frame where the battery will be mounted.
- Insert four hold-down bolts into the holes and tighten them to secure the battery in place.
- Next, use a ratchet strap to secure the battery in place. Make sure that the strap is tight enough so that the battery can’t move around.
- Finally, use a wrench to tighten the hold-down bolts. This will ensure that the battery is securely in place.
CAUTION: Don’t install your lithium car audio battery under the hood. While most lithium batteries for car audio operate best under warm conditions (15 to 35), the under-the-hood engine heat can be too much that it degrades performance.
Hook Up the Cables and Run the Amp
- Connect the positive wire connector of the alternator to the positive terminal of the charge controller.
- Hook the negative wire connector of the alternator to the negative terminal of the charge controller.
- Connect the positive wire of the charge controller to the positive terminal of the battery.
- Hook the negative wire of the charge controller to the negative terminal of the battery.
- Connect the positive wire of the amp to the positive terminal of the lithium battery.
- Hook the negative wire of the amp to the negative terminal of the lithium battery.
- Secure the positive and negative connections to the battery with appropriate-sized nuts.
- If needed, cover the battery with a battery box or similar enclosure to protect it from the elements.
How Electricity Flows
Whether you subscribe to the conventional current theory that electricity flows from the positive side of a power source through a load and back to the negative terminal, or to the electron theory that holds that electrons flow from negative to positive, what matters is that an electrical circuit is a loop. Your load, be it a light bulb, radio or amplifier, needs to have two electrical connections. Power flows from the electrical source through the load and back to the source again. The current in both conductors is equal.
In the “good old days,” installing an amplifier in a car or truck involved having your installer run a large-gauge wire from the battery’s positive terminal through a fuse holder or circuit breaker to the positive terminal of the amplifier. The wire from the amplifier’s ground terminal would be bolted to the chassis of the vehicle.
Until about a decade ago, most cars and trucks were built with steel, and the chassis or unibody components were spot-welded together. As a result, there was often enough surface area between the panels to allow current to flow from the ground of the amp back to the negative terminal of the battery or alternator.
What’s Wrong with a Chassis Ground?
The ground connection needs to be secure. Because the cable is of a reasonably large gauge, it can experience moderate loads during acceleration and braking and from the vibrations associated with regular driving. This stress can loosen the connection and cause intermittent behavior or damage.
You’d think removing paint, primer and coatings would be easy, but the number of poor grounds we see is amazing. In some cases, especially with cars that are painted silver, some primers and corrosion-resistant coatings can look similar to bare metal.
In many modern vehicles, lighter metals such as aluminum are used in vehicle construction. These materials don’t conduct electricity as well as a high-quality copper conductor. What’s more concerning is that many new vehicles are assembled with high-strength adhesives and even two-sided tapes from companies like 3M, Dow Chemical and Henkel. These materials are not electrically conductive.
Ohm’s Law in 20 Seconds
Whenever current flows through a device or conductor with resistance, a voltage is produced across that device. In the case of a piece of wire, the resistance is typically low, so very little voltage is wasted. When the current flow is significant, we can see several volts across the wire, and it will heat up. To calculate the voltage drop across a resistance, multiply the current flow (in amps) by the total resistance of the device (ohms). For example, 2 amps of current flowing through a 4-ohm resistor results in 8 volts being produced across that resistor.
Feeding your high-performance amplifier with the power it needs means delivering as much voltage as possible to the power terminals. If the amplifier draws a significant amount of current, then your installer will need to use large-gauge conductors to prevent voltage losses due to the resistance in those conductors. This same logic applies to the ground return path. A test performed several decades ago by one of the engineers at JL Audio in Miramar, Florida, showed that most vehicle chassis have a resistance equivalent to a piece of four AWG cable. Modern vehicles are much worse.
Let’s say you have a good quality 1,400-watt amplifier like the ARC Audio ARC1000.4 DSP we tested a few months ago. This amp produced 1,406 watts of power (at 1% distortion) when provided with 13.37 volts at the power terminals. It drew 137.1 amps of current to deliver this power (at an impressive 76.7% efficiency). If your vehicle had a 16-foot run of all-copper, CTA-2015 compliant, four-AWG power cable to feed the amp, there would be a voltage drop of 0.588 volts across the length power cable. The ground return path (assuming it has the same resistance) would result in a similar loss of voltage at this current level. Your electrical system would need to be able to supply the battery with 14.546 volts and have a spare 137 amps of current capacity available. For a full-sized sedan or truck, these numbers are quite reasonable. So, you might be able to get away with using the chassis as a ground – if you know it’s all-steel from front to back.
DIY Installation Tips for Car Stereo Amplifiers
If you like working on your car, you’re probably keen to upgrade your car stereo system on your own.
This is a great opportunity to learn more about how your stereo works and how to get the best sound from it. Installing an amplifier and accompanying speakers also lets you develop a few handy skills you can use for future upgrades and tweaks.
While this job is tricky, if you feel confident in your wiring capabilities, go for it! And if you need a hand along the way, don’t hesitate to contact the car stereo specialists here at AudioMotive.
What You’ll Need
Car amplifiers usually don’t come with wiring, so you’ll need to buy wiring to hook up your amp to your car stereo system.
Power and Ground Wires
To supply power to your new amplifier, you’ll need to connect it to your vehicle’s electrical system with power and ground wires.
These wires must be thick enough to handle the amp’s power demand. A wire that isn’t thick enough could cause problems for your amp’s operation, or at the very least prevent it from putting out its rated power.
Refer to your amp’s instructions to determine the recommended wire size to use. Wire size is measured in diameters, usually referred to as a gauge. The lower the gauge number, the thicker the wire you’ll get.
Take time to measure the distance between the car battery and the amplifier so you can get the right length of wires.
An In-Line Fuse
An in-line fuse on the main power cable, within half a foot of the connection to the battery, is a must. This fuse protects you, your car, and your stereo system from a short circuit that could cause a fire.
A typical 16 to 20-foot fuse run is safe using one of the following:
- 25-amp fuse for 10-gauge wiring
- 60-amp fuse for 8-gauge wiring
- 100-amp fuse for 4-gauge wiring
- 250-amp fuse for 1/0-gauge wiring
Alternatively, look for amplifier wiring kits that suit your amp specifications. Amplifier wiring kits include fuses and matching power, ground, and turn-on wires in one convenient package to help remove any potential for confusion or damage.
RCA Cables and Speaker Wires
Amps typically require RCA cables to get input signals from the stereo receiver’s output. RCA cables come in stereo pairs and a variety of lengths.
When running speaker wires from your amp’s output to the speakers, you can use any size wire from 18- to 14-gauge. For subwoofers, use wires between 16- and 12-gauge.
Your Step-By-Step Guide
Once you’ve got all your components and wiring ready to go, it’s time to get to work!
NOTE: Installation specifics depend on the amp equipment you purchased and the make of your vehicle. When in doubt, call the pros!
Step 1: Disconnect the Car Battery
Your car should be parked on a flat surface with the parking brake engaged. From here, pop open your hood and disconnect the battery, starting with the negative terminal. This will help prevent electrical shorts and shocks while you go about installing your amp!
Step 2: Mount the Amp
Choose a safe location to securely mount your amp. The manufacturer will usually include a few recommendations in their included instructions.
As a rule of thumb, amps produce plenty of heat, so they need a few inches of air space on all sides to help keep cool. Don’t mount the amp upside down! While you might be able to save space, the heat it puts out will just radiate back into the amp, causing overheating and creating a fire risk.
You also need to ensure there’s enough room to connect wiring and adjust the controls. But that’s not all! Your amp should also be at least three feet from your stereo proper to avoid interference and radiant noise. Bolting the amp directly onto your car’s metal chassis is also an invitation for noise problems. Use rubber grommets around mounting screws, or mount to a wooden board before attaching it your car’s body.
Possible locations to mount your amp include:
- On the passenger-side firewall—use short wires and patch cords
- In the trunk/hatch area
- Under a seat
Note that you will need to conceal the wiring for safety and appearance. Depending on the location you choose, you will need to run the wiring under the dash, kickpanel, door scuff plate, or pillar trim panel. These panels can usually be removed by unscrewing and/or prying them up at the edges.
Use plastic wire ties to secure the wiring, especially if behind the dash, to ensure the wires don’t interfere with any moving parts of the vehicle.
Step 3: Install the Power Wire
You will need to route the power wire from the car battery, through the car’s firewall, and through the car’s body to the amp.
To do this, find an unused grommet in the firewall to pass the wire through. Alternatively, you can find one with wires passing through and enough room for the power wire to fit through as well.
Advantages of Adding 2 amps to a Vehicle Diagram
As shown in the “2 amps in a car graphic,” there are various advantages to adding two amplifiers to a car audio system:
Extra power:
You may double your vehicle audio system’s total power by installing a second amplifier, providing louder and clearer music.
Better audio quality:
You may divide the audio signal into various frequency bands by employing two amplifiers and send each to a different speaker. This enables a more precise and balanced music reproduction, enhancing the system’s overall sound quality.
Flexibility:
Having two amplifiers gives you greater freedom to modify the sound of your system. You could separately change the volume levels of various speakers and frequency bands.
Safety:
By adding a second amplifier, you may lessen the stress on a single amplifier, extending the life of the amplifiers and lowering the possibility of harm to your vehicle’s audio system.
Better Sound Staging:
Using two amplifiers allows you to power various speakers with various amplifiers, which improves sound staging and creates a more immersive audio experience. It’s important to note that, to benefit from these advantages, you need to have a proper installation and a good understanding of car audio systems and the amplifiers you are using.
Frequently Asked Questions
What gauge wire should I use for my ground and power cables?
The amplifiers’ amperage draw will determine the size of the wire. For the ideal wire size, consult the wiring schematics for the respective amplifiers.
Can I use a single amplifier for the speakers and a separate one for the subwoofer?
Yes, you may supply the subwoofer with one amplifier while using the other to power the speakers. You can independently alter the subwoofer and speakers’ volume levels.
Are RCA cables required?
The audio signal is usually sent from the head unit to the amplifiers via RCA connections. Although not necessarily essential, they can aid in noise reduction and quality improvement.
Do the speakers’ and amplifiers’ impedances need to match?
It is crucial to match the speakers’ impedance and the amplifiers’ impedance to ensure optimum performance and prevent equipment damage.
How do I ground the amplifiers correctly?
Proper grounding of the amplifiers is essential to avoid hum and noise in the audio stream. The amplifiers should connect to the car’s chassis using a grounding wire.
Are the amplifiers self-installable?
Although installing the amplifiers yourself is feasible, it’s vital to grasp the amplifiers you’re employing and vehicle audio systems in general. It is essential to consult a professional if you are still getting familiar with the wiring and installation.
How can I test the system after installation?
After installation, test the system by turning on the head unit and checking that everything functions as it should. Make any required changes or connections after listening for distortion, noise, or other problems.
Conclusion
The process of installing an amplifier usually entails running power and ground wires to the location of the amplifiers, running RCA cables and speaker wires between the head unit and the amplifiers, connecting the power and ground wires, RCA cables, and speaker wires to the correct terminals on the amplifiers, and testing the system to make sure everything is functioning as it should.
It’s crucial to remember that it’s ideal to consult a professional to install it for you if you’re unfamiliar with the wiring or installation.
Expert Opinion
To avoid electrical shorts and protect your safety, always disconnect the negative battery line before doing any repairs on the automobile. To guarantee good connections, use the right size wire for the amplifiers’ amperage requirements and refer to the wiring schematics for those particular amplifiers.
I am an Automotive specialist. I graduated from Michigan with Bachelor in Automotive Engineering and Management. Also, I hold degrees in Electrical and Automation Engineering (BEng), Automatic and Industrial Electronic Engineering, and Automotive Technology. I have worked at General Motors Company for over five years as the Marketing Operations Production Coordinator. Now, I own my garage in Miami, Florida. I love cars and love to share everything about them with my readers. I am the founder of the Automotiveex blog. where I share everything about automotive, like car news, car mechanical issues, and anything else that comes up in my blog posts.