Custom Battery Cable Assembly: Design the Battery Cable for Your Needs

Battery cables hold great importance in car battery systems. As you choose higher quality wire assembly, it directly affects your system efficiency. However, quality depends on the size of the cable as well as the way you install and maintain it over time. Let’s dig into more details on Custom Battery Cable Assembly.

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What are Battery Cables?

Battery cables connect the terminals of your vehicle’s batteries to the remainder of the vehicle’s electrical system, which includes the starting, charging, and ignition. 

It is made up of two wires of a substantial gauge. The positive battery wire is wrapped in a red sheath and is responsible for connecting the battery to the computer in your vehicle. The negative battery cable is a wire encased in a black sheath that links your car’s chassis to the battery so the battery can be grounded. This cable is also referred to as the grounding strap or grounding cable. Together, they produce a closed circuit that enables the flow of power uninterrupted.

A battery cable is the most effective when connecting the batteries to their starter. The strength and endurance of the battery cable are best displayed when it has a direct connection and very few sharp turns. This cable is typically rated to withstand 60V DC and comes in various gauge sizes. Various cables can work for your purpose, but it all depends.

How do Battery Cables Work?

You can frequently find battery cables in buses, boats, trucks, recreational vehicles, and tractors. The battery cables in your car are clearly labeled and easy to locate. As a bonus, the starter solenoid is often the first place where a positive connection happens. The journey then continues to the end, where the starter has a positive lead. When the right switches are turned on, the negative battery cable is connected to the car’s chassis to electrical power parts like the starter.

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Construction of Battery Cables

When it comes to industrial machinery, the battery cables and the lugs required to connect a battery are constructed out of thick copper wire. However, you can purchase jacks and cables independently.

Cable Itself


Battery cables come in a wide variety of wire gauges that assist electricians in satisfying power demands. And the larger the cable, the more power it can carry. So, the current flowing that can safely run through a cable depends on its function, location, and ambient temperature.

One of the most prevalent problems with improper installations is a battery wire with the wrong gauge, which might pose a greater risk than some think. If the wire is excessively thick, it won’t conduct electricity efficiently. Also, a thin wire gauge increases the risk of a short circuit, which might start a fire in the engine compartment. Hence, ensure everyone participating in the selecting process has access to amp and size charts to avoid this problem.


The stranding has a major impact on the movement of cable assemblies. Due to the fixed nature of the cable as it connects the battery to the generator or starter.  Also, a lower strand count is frequently sufficient for automotive applications, making the cable more flexible than necessary.

Applications exist where cables’ elasticity is essential, such as when you often move the components or the cable constantly bends. Then, more strands are required to provide the desired degree of adaptability. Since electricity often travels along the wire’s exterior, more wire surface results in somewhat improved conductivity at higher strand counts. In some contexts, this is crucial.

Conductor Material

Stereo shops frequently sell OFC (Oxygen Free Copper) wire to connect speakers or high-powered amplifiers. However, do not just throw away your cash. It is a ploy by smooth talkers to part with more of your cash. What makes this variant so distinctive? The minimum purity of copper in the common wire is 99.90%. Of the total copper content, OFC is 99.5% pure. However, obtaining an additional 0.05% copper is a nice bonus.

However, there is one significant drawback, cost. Most of the time, the cost of OFC is TWO TIMES that of a comparable length of ordinary cable. Also, you’re paying 100% more for a marginal increase in copper content. In terms of electricity, there is zero discernible difference.

Also, say no to the CCA wire as well.  It is because these wires will need to be around two sizes larger to match the conductivity of a copper-clad-in-aluminum (CCA) wire because aluminum only possesses 60% copper. Put another way; a 2 gauge CCA wire would be required to do the same tasks as a 6 gauge copper wire. To solve this problem, you need to acquire copper wire.


Unlike their household counterparts, battery cable assemblies used in vehicles need to be able to survive the high temperatures and harsh conditions found under the hood, including the oil and chemicals used to maintain the engine. When it comes to cars and other vehicles, nothing except SAE-type SGX and SGT battery cables will do.

The maximum operating temperature for PVC-insulated SGT cable is 105 degrees Celsius. SGX cable, thanks to its cross-linked insulation, can tolerate temperatures of up to 125 degrees Celsius and is somewhat more abrasion-resistant. Whether using the cables inside or in a location where it will face humidity, heat, or sunshine, NEC or UL-rated wire is necessary for the task.


 Battery connections can be made with various connectors, including the traditional battery terminal that slides over a ring lug and leads post terminal. They are available in straight and angled shapes to accommodate a wide range of wire diameters. Also, they are primarily made of copper and can be purchased either plated or unplated.

Things to Consider When Designing your Battery Cables

For designing a custom cable assembly, you need to look into the following details.


Choosing an appropriate length for an automobile wire or cable requires considering voltage loss. Because of the increasing resistance, the voltage is at a sufficient level as the cable length increases. Since the wire’s resistance depends on its area over distance, thinner wires with a larger gauge will have higher throughput than thicker wires with a smaller gauge.

For a 12V DC system, the output voltage at the end of a 20-foot cable run with a 4 AWG battery cable would be 1.0% or 11.8 volts. However, it is possible to simplify calculating voltage drops by using online calculators.

Installation and maintenance

After determining the appropriate specifications for a battery cable, you must carefully connect it to the battery terminal. Most dc link post meltdowns can be traced back to a loose connection that has compromised the battery system’s performance. There will be less of a chance of something going wrong if you use cables of the right size and appropriate connectors and keep up with routine maintenance.

There is a common lack of attention to maintenance despite its ease. Hence, ensure the battery wires haven’t cracked over time and are still in good shape to prevent terminal corrosion. Moreover, keep the lid of the batteries clean and the battery posts clean at all times. Take care to have your vent caps in place and your lugs firmly attached to the battery posts.

Custom Battery Cable Assembly: Automobile battery charging

Caption: Automobile battery charging

Custom Battery Cable Assemblies according to your needs: 

The following are the most popular cable assemblies you can have premade.

Marine Rating Cables

The designation “Marine” describes various wire types. It is best for a marine or “wet” setting. You must also be able to put out your fire if one breaks out. Therefore, manufacturers mandate a specific marine rating for any device you will use underwater.

Battery Cable With Fusible Link or Fusible Link

If the cable gets too hot and the fuses open, the high-heat insulation of the fuse connection will keep the cable safe. The most common application is in the wiring of vehicle alternators. You can opt for the relay wires for diesel engine plugs and heating systems in extreme conditions.

Custom Battery Cable Assembly:  Cable with a Tapered End

Manufacturers make the cables’ tapered post connectors of lead, brass, or forged bronze. It contains 8-gauge wire heads with lead casting and comes in a wide range of coating options. In addition, it provides a wide variety of options for protecting connections, like heat shrink tubing.

Custom Battery Cable Assembly: Batteries with a Ring-to-Ring Connection Cable

You can crimp multiple wires onto a single lug when using ring-to-ring battery cables. Furthermore, dipping it in a tin makes it more corrosion-resistant and strengthens its pull.

Custom Battery Cable Assembly: Booster Cables

When you’re short on room but need to charge the car’s battery, the booster cables come in handy. Also, manufacturers make it with components designed specifically for its intended use.

Custom Battery Cable Assembly: Flat or Ground Cables

A thin strap used to anchor to the ground requires almost no clearance. Several crimping options are available, including lugs, open barrels, and lead cast voltage level connectors.

Custom Battery Cable Assembly: Cable Repairing Splice

Battery packs with cable splice repair tools make it simple to swap out damaged or worn connectors. Moreover, replacing a battery wire harness is more work than mending a broken battery connector.

Disconnect it from the battery, remove the insulation, solder it in the new terminal, and reconnect it. Splices in battery cable repairs are more practical and economical than replacing the complete cable because you will change only the terminal end of the cable.

Custom Battery Cable Assembly: Battery pack in the electric car

Caption: Battery pack in the electric car


Assembling the battery wires is simple if you are familiar with the correct elements. Hence, research the different battery cable components and purchase them from authentic sources. Also, remember the cost should be minimal. Here at Cloom, we offer wiring harness solutions and custom cable assemblies so that you don’t have to worry about perfection.

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Enjoy a free sample worth UP TO $100!
Explore our custom services now. Email us at [email protected] for more details.

Hey, I am John, General manager of Cloom and OurPCB.

I am a responsible, intelligent and experienced business professional with an extensive background in the electronics industry.

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