Battery Cable Lugs: How To Make Your Battery Cable

To ensure your car’s electrical system functions as intended, have a high-quality battery cable. If your battery cable corrodes or no longer supports conduction, your car might lose electrical power or fail to start.

Therefore, it’s best to replace any faulty battery cable lugs and terminals to ensure your car’s battery is fully functioning.

What is the Difference Between Cable Lugs and Terminals?
- Types of Battery Lugs
- Types of Battery Terminals
Build your Battery Cables
- Prepare Parts
- Process to Crimp
Conclusion

What is the Difference Between Cable Lugs and Terminals?

Battery terminals and battery lugs appear similar due to the strong connection they create between the system and the battery cable.

However, the position of the posts or studs could be very different, which brings us to the primary difference between terminals and lugs.

Lugs connect your battery cable to the starter post or solenoid.

On the other hand, terminals are commonly used in marine and automotive applications to connect your battery cable to the battery.

Often, people use lugs for bigger gauge applications for grounding and power draw.

With terminals, you’ll require both positive and negative polarity terminals for a good connection.

Types of Battery Lugs

Generally, lugs are connected to the cable by inserting the conductor into the barrel of the device.

Then, you’ll have to weld, solder, or crimp the barrel to the conductor to ensure the electrical and mechanical joints are secure.

Crimp lugs are ideal for low amperage and low voltage applications.

On the other hand, compression lugs are better suited for high amperage and high voltage applications.

Lastly, soldered lugs are mainly utilized in scenarios where you want a permanent and strong connection.

Often, lugs are made using copper because of conductivity. Another common choice for lugs is tinned copper.

Such lugs are similar to regular copper lugs in construction but provide a tinned coating. The coating helps reduce corrosion.

Therefore, if your project is in a harsh environment, it’s best to opt for tinned copper lugs.

Lugs are available in a variety of angles. Angled copper lugs are ideal for extra clearance and space-saving stacking.

Also, lugs are available in different sizes to ensure the connection between the system and the battery is reliable and secure.

Loose connections could result in voltage drop, thus affecting performance and reducing battery life.

It’s important to ensure the lug size matches the battery terminal size and cable diameter.

The lug’s connection end is then secured to the connection point via a bolt, spring clip, or screw.

The lug’s connector end is picked mainly for its compatibility with the terminal type.

Screw terminals use U-shaped or fork lugs, press-on terminals use pin lugs, and bolt-on terminals use O-type or closed ring lugs.

Starting system

Types of Battery Terminals

Battery terminals are often made of either copper, brass, or lead. Each material offers unique merits and demerits, such as corrosion resistance and conductivity.

The three main types of battery terminals include;

Side post terminals – generally used in newer cars. They provide secure connections and save space. However, they aren’t as versatile as other options.
Top post terminals – they are the most popular and are found in older automotive batteries. Unlike the previous option, they’re versatile and accommodate several cable attachments.
Universal terminals – these can function as both side post and top post terminals, therefore offering flexible installation.

Also, consider the various battery terminal shapes to determine the best fit for your intended application.

The straight copper terminal is the most common shape. However, you can opt for a parallel terminal for special applications.

Unlike the straight terminal, the parallel terminal allows you to use two wires.

Furthermore, if you’re low on space and require a battery connection, opt for the left-angle and right-angle terminals.

These are ideal for tight spaces where your standard straight terminal wouldn’t fit.

Caption: Battery Terminal

Build your Battery Cables

If you consider yourself handy and buy the parts and assemble the cable yourself, follow the guide below.

Prepare Parts

Wire: SGX, SGT, marine battery cable, 8 and 10 AWG fuse link wire, and 4/0, 3/0, 2/0, 1/0, 2, 4, 6, and 8 AWG black or red.

Lugs: Heavy duty, 45⁰ and 90⁰ lugs, typical ring terminals, and splices. AWG categorizes items. Also, lugs are categorized according to bolt-hole size.

Terminals: Stud top/side post top post (flag, elbow, or straight) and some extra wire adapters and terminals. Battery terminals are categorized according to negative or positive (slightly bigger).

Battery boot and cover: Alternator, elbow, top post, flag, side post, and starter lug covers.

Crimpers: hammer crimper, bench mount, and a short or long handle.

Professionals recommend crimping as the ideal method for attaching ends. If executed properly with the right equipment, the crimp will have no air spaces, eliminating the need for a solder.

Soldering is rather difficult to perform. If you use excess heat, it becomes tough on the installation.

However, if you don’t use enough heat, the solder becomes cold, resulting in a poor mechanical and electrical connection.

Also, soldering can wick up the wire, reducing its flexibility. Furthermore, soldering requires solvents for cleaning, flux, and hazardous lead solder.

Loom, heat shrink, and wire ties: Convoluted loom, adhesive-lined thick wall heat shrink, and premium UV stabilized wire tires.

Negative battery cable

Process to Crimp

Follow the steps below to crimp.

Step 1: Determine Cable Length

Plan the run from one point to another, not forgetting to consider the length of the barrel.

Mount the lug on the last terminal to hold it in place while checking the length.

Then, you can hold your cable next to the lug from that point to the next lug.

Step 2: Cut to Length

Use a pair of cutters to cut your desired cable length.

Step 3: Mark Insulation Strip Length

Place your wire next to the lug. Find the wire’s end at the lug’s point, which begins tapering down to the flat area.

Put a mark where the cable insulation will be pushing down the lug. Ensure the strip isn’t too long, as it won’t be aesthetically pleasing.

Also, ensure it’s not too short, as there won’t be enough room for the wire inside the lug for a good crimp.

Step 4: Strip Insulation

Use cable cutters or side cutters and not your ordinary wire strippers. Cut roughly ¾ through the insulation and avoid touching through the copper wires as the strands easily nick.

Step 5: Remove Insulation

Now bend the wire at the cut mark, snapping the insulation. That will separate from the rest.

If it fails to separate the first time, you could try pressing a knife on the spot.

Once you separate the insulation, you can pull off the cut section to expose the wires.

Step 6: Insert Wire and Ensure Fitment

Before inserting the wire, inspect the lug for oxidation or defects. If any is present, it’s best to use a different lug. If you don’t have access to a different lug, you can try gently scrubbing the lug with a wire brush.

Push the lug over the striped section of the wire while ensuring a good length of the insulation is stripped back.

Step 7: Prepare Crimper

It’s best to get a crimper with a die for AWG sizes. That way, you can guarantee a more secure connection. After installing the right die, ensure you close the release valve.

Step 8: Crimp

Place your lug in the dies and pump the crimp’s handle several times to ensure a snug grip. If the lug is big, you might need to crimp it at two points. Therefore, ensure you align the dies as close as possible to the lug’s open end.

Once the dies hold the lug, ensure no wires are sticking out. Failure to properly insert the wire in the lug will result in an unsuccessful crimp.

Step 9: Finish Crimping

Keep pressure on the handle until the dies meet.

Then, release the pressure and prepare to move on to your second crimp. Put your lug back in the crimper, but this time, the area that wasn’t crimped during your first crimp. Then, continue to repeat the procedure of the first crimp.

If you used the correct die configuration and proper tool, the lug and wire should be inseparable even after a couple of tugs.

However, if the wire slides out, rethink your die selection and go for a smaller size. Also, if the point at which the dies appears squashed, you should crimp again but with a bigger die size.

Step 10: Second Lug Crimp

Before crimping the lug on the cable’s opposite, be careful because with thicker, you can’t twist your cable to make up for a wrongly oriented lug. It’s best to mark the lug and wire where to line up things while crimping.

Once you’ve established the orientations, you can crimp the cable’s second lug.

Step 11: Test Fit

Once you’ve successfully crimped your cable, test it to ensure proper rotation and length. If all is well, you can proceed to the next step.

Step 12: Heat Shrink

If you have a 4/0 cable, your heat shrink tubing should follow a 3:1 shrink ratio. Once the tubing is flat, the wire should measure 1½” wide, and you cut off a 3-inch piece for each end. Cables with a smaller diameter often have shorter tubing.

The goal of heat shrinking is to prevent moisture from seeping into the crimp and reduce cable stress from flexing.

Use your heat gun to heat the shrink tubing. The wide tip should help spread the heat across the tubing’s body. Keep turning the cable to ensure the entire is consistently being heated.

Now, you have a fully crimped cable that is safe and ready for use.

Caption: Heat Shrinking Cable

Conclusion

There, you have all you need to know about battery cable lugs. Also, for all your battery cable crimping needs, contact Cloom Tech.