What Is a Battery Jumper Clamp? Types and Selection Criteria

A battery jumper clamp is a removable alligator-type clip on the end of a jumper or charging cable that grips the battery terminal post with spring-loaded jaws.

A battery jumper clamp, also called a battery clip, is an alligator-type connection clamp attached to the end of a jumper or charging cable that grips the battery terminal post with its spring-loaded jaws. It provides a temporary, removable connection when starting a vehicle with a flat battery from another battery or when charging a battery. Despite the word "pliers" in its Turkish name, it is not a crimping tool for ferrules or lugs; it is the connection part that stays on the end of the cable.

Types

• By plating: Copper plating emphasises the conductivity of the contact surface; cadmium plating emphasises resistance to corrosion.
• By colour: The red clamp is for the positive (+) terminal and the black clamp for the negative (−) terminal. Clamps sold singly come in one colour.
• By sales unit: A single clamp replaces one broken or worn end; a red and black set is for making up a new pair of cables.

Selection criteria

1. Current and cable cross-section: The clamp must withstand the starting current carried by the cable it is fitted to and must suit the cable's cross-section; an undersized clamp heats up at high current. The clamp product data in the catalog do not state a current rating or a compatible cable cross-section; confirm these with the product advisor before ordering.
2. Jaw opening: The jaws must grip the battery terminal post fully. Batteries in trucks, tractors and construction machinery have larger terminal posts.
3. Cable connection: Check whether the cable is fastened to the clamp with a screw or with a lug; with a lug connection, the lug must be crimped with a suitable lug crimping tool.
4. Insulation: An insulated grip reduces the risk of touching the vehicle body or the other clamp while the clamps are connected.
5. Plating and environment: Corrosion resistance matters in damp conditions or for a cable kept in the vehicle for long periods; contact conductivity matters for a jumper set used often.

Common mistakes

• Letting the clamps touch while connected: The short circuit causes sparks and strains the cable and battery.
• Mixing up the terminal colours: Reverse connection can damage the vehicle electronics; always connect red to positive.
• Connecting to an oxidised or painted surface: Contact resistance rises, the clamp heats up and the starting current does not flow; clean the terminal post and make the chassis connection on bare metal.
• Gripping with the tips of the jaws: Jaws that do not fully grip the terminal post slip and spark.
• Mistaking the clamp for a crimping tool: Crimping cable lugs or ferrules requires a lug or ferrule crimping tool.

Battery jumper clamps in the catalog

All 6 active products in the Battery Jumper Clamps category are from KSN (Konsan) and can be ordered directly:

For models sold as a set, one sales unit consists of one red and one black clamp. For ready-made jumper cables see Battery Jumper Cables, for checking battery condition Cell and Battery Testers, and for crimping lugs onto cable ends Lug Crimping Pliers.

Frequently asked questions

Are a battery clip and a battery jumper clamp the same thing?

Yes. Both names refer to the connection clamp at the end of a battery cable that grips the terminal post with spring-loaded jaws.

Why are the clamps red and black?

So that the connections are not mixed up. The red clamp goes to the positive (+) terminal, and the black clamp to the negative (−) terminal or the vehicle chassis.

Should I choose a copper-plated or a cadmium-plated clamp?

Copper plating stands out for contact conductivity in a jumper set used often; cadmium plating stands out for corrosion resistance in damp conditions or on a cable that will be stored for long periods.

How many amps can a battery jumper clamp carry?

The current rating depends on the clamp's size and construction. Since the product data of the HWA models in the catalog do not state a current rating, ask the product advisor before ordering whether it suits your cable and vehicle.