Some vehicles, such as race cars, have difficult-to-access batteries, while others might have them in dangerous areas near the engine block. External battery jumper blocks can help bring these power sources to accessible areas for various reasons.
These external battery terminals are relatively cheap devices, so let’s look at their benefits and how to pick the right one to help you select the most suitable piece for your vehicle. Read on to learn more!
Table of Contents
- What Is an External Battery Jumper Block?
- Advantages of Using an External Battery Jumper Block
- How To Choose the Right External Battery Jumper Block
- How To Use an External Battery Jumper Block
- Maintenance and Safety Tips for External Battery Jumper Blocks
- Summary
What Is an External Battery Jumper Block?
External battery jumper blocks are external battery terminals that extend the positive and negative lugs to a suitable and convenient location in your vehicle.
These devices are compatible with all vehicles but are commonplace in the racecar industry because these cars have hard-to-reach power sources.
You can also use them in RVs or trailers for off-grid living. With their batteries stored deep in the chassis, an external battery jumper block can help you access the power sources to draw power.

An RV/camper fitted with solar panels on the roof for battery charging
Or you can use the block to recharge dead batteries using solar, plug-in ports, portable car battery chargers, etc.
Advantages of Using an External Battery Jumper Block
These terminals have the following features and benefits.
Enables Remote Charging and Starting
With the external battery jumper block conveniently mounted at an easy-to-reach spot, you can charge the vehicle’s battery pack or even jump-start it without the hassle of opening the hood. So, the keyword here is convenience.

Quick car battery recharging using jumper cables to start the engine
Stable Connectivity
Most of these jumper blocks feature threaded or hexagonal lugs that create an uneven, grippy surface for holding the crocodile clips or clamps when charging or jump-starting.
This firm connection is necessary to prevent arcing when the high voltage current moves through the conductors.
Heavy-Duty Construction
External battery jumper blocks have multiple parts made using different materials. But all are heavy-duty materials that best suit their task.
For instance, the terminals are usually pure copper, enabling them to handle hundreds of voltage ratings.
On the other hand, the bracket is stainless steel, a sturdy material that holds the terminals and all other components securely on the mounted surface.
There’s also the protective coating. The steel part usually has a powder or protective paint to prevent corrosion, while the terminals have color-coded dust caps for protection and polarity indication.
This combination makes the structure waterproof and dustproof.

The electrical connection required to jump-start a car
Reliable Electrical Connections
This kit comes with thick, pure copper wires that enable you to mount the battery or external terminals where you want.
The gauge can vary depending on the recommended application or price, but the cables are generally thick.
However, the most vital parts are the thick, heavy-gauge terminals. These enable you to use even 0 gauge wires to transmit high-voltage currents without overheating.
Wide Compatibility
External battery jumper blocks are not limited to car applications. You can use them in equipment, boats, tractors, RVs, ATVs, UTVs, mowers, etc.

Two all-terrain vehicles in a desert
Easy to Install
Not only are these terminals easy to install, but they also allow flexible mounting locations.
The stainless steel bracket features two or three mounting holes, meaning you only have to drill matching holes in your vehicle’s chassis.
Once drilled, you can use bolts and nuts to secure the bracket firmly to your vehicle. You can also use rivets, but nuts and bolts are better.
Built-in Safety
To prevent accidental contact, external battery jumper blocks feature safety tabs between the terminals. So, you can be sure of zero short-circuiting at the terminals after hooking the clamps firmly.
How To Choose the Right External Battery Jumper Block
You need to check the following factors.
Durability
An external battery jumper block must have a durable construction to transmit electrical power reliably.
Durability and reliability go hand-in-hand, so ensure the device has a sturdy construction that can withstand the stresses of the job.
A durable jumper block should have a stainless steel frame or bracket with a protective coating to protect the structure from corrosion.
At least make sure the block is dustproof and waterproof.
Compatibility
Although these blocks are widely compatible, check the specific ratings of the device to ensure it meets your application requirements.
For instance, ensure the wires and their thickness or gauge are enough for the voltage you’re handling. Also, check the terminal gauge rating.
Ease of Installation
Mounting the bracket and connecting the wires to the battery should be easy.
The terminals should have bolts and nuts on the other side for attaching ring terminals from the battery wires, while the bracket should have holes drilled for chassis mounting.
How To Use an External Battery Jumper Block
Before using an external battery jumper block, you have to mount it at a convenient location.
After that, connect the jumper cables to the rear side using ring terminals and tighten the nuts that hold each ring.
Link the other end of these wires to the battery lugs or power bank terminals to make the jumper block live.
Ensure the negative/black power post connects to the terminal with a black cap and the red/positive post links to the red-capped terminal.

Polarity-marked car battery terminals using red and black color codes
You can tap electrical power or recharge the battery cells from these terminals using jumper cable clamps or terminal connectors to extend the battery life.
After use, disconnect the clamps or connectors and cover the terminals for safety.
Maintenance and Safety Tips for External Battery Jumper Blocks
- Always cover the jumper block terminals using the dust caps when not using them.
- Keep the terminals clean at all times
- Clean any salt formation or corrosion that occurs on the terminals

Salt/corrosion build-up on a car battery terminal
- If the lugs are removable, tighten them to the jumper block before use
- Check the bracket mounting on the frame regularly to ensure it is firm
- Route the battery wires through a path with no sharp objects or moving parts
- Secure the jumper cables firmly to the frame
- Follow the manufacturer’s recommended installation instructions, safety precautions, and maintenance procedures.
Summary
External battery jumper blocks present one primary advantage, which is convenience.
The universal battery post brings the terminals closer to you for easy connection when recharging or drawing power from the battery.
You should consider having a battery disconnect switch to these terminals for additional safety, and we can help you wire the entire system.
Contact us for recommendations of the best jumper blocks and wire harnesses in the market.