The question posed by the title of this article is actually so common on Google that it seemed necessary for us to answer it here.
You may have noticed that marine battery wire is often sold at a premium over, say, automotive battery wire. You might also have noticed that marine and automotive battery wires of the same gauge have basically the same current-carrying capacities and voltage ratings.
Therefore the question – can you use automotive battery wire instead?
From a functional standpoint, it would hardly make a difference. Both the wires can serve as leads from the terminals of a battery to provide power to the engine and peripheral equipment.
But, be that as it may, in a word – no, you can’t use automotive battery wire in lieu of marine battery wire, when the latter is called for.
Well, now let’s take a look at the fact that it’s not just battery wire – but all marine-purpose wire has the same attributes.
If you’ve ever so much as wired a bilge pump, you’ll know that if you strip off some of the insulation from marine battery cable, it doesn’t look copper.
Looks can be deceiving, though. It isn’t aluminum, and it isn’t even silver, although you wouldn’t be amiss in suspecting so. Aluminum has very good conductive properties and silver is even better- the best electrical conductor of all, in fact.
But marine battery wire is not silver or aluminum for that same reason that it doesn’t appear to be copper, even though it is.
Marine battery wire is, in fact, often made up of many, fine copper conductors. That silvery appearance comes from the fact that all the conductors are individually tinned.
But why is marine wire tinned? Well, it’s not a cerebral exercise to figure out just why. It has nothing to do with improving current carry capacity or voltage rating. It’s all about the environment.
Do you know why old copper pennies get dark, and why the Statue of Liberty is green? It’s called oxidation, and it’s what happens to copper in oxygen-rich, corrosive environments.
Elemental copper is an excellent electrical conductor. Copper oxides are not. As a result, marine-grade wire and cable are made with individually tinned copper strands. This gives them a better measure of protection against the elements.
As a result, it is necessary to provide an additional degree of protection against corrosion. That tinning helps to coat the copper conductors and shield them from the inside, providing an airtight, watertight cover that seals them off.
Basically, if you use automotive-grade battery cable in place of marine grade cable when marine grade is necessary, you’ll receive a remarkably shortened operational lifespan in exchange for your efforts. Automotive-grade cable is naked copper and will corrode away in record time.
There’s one more reason that marine-grade cable is in some situations considered superior, though.
In addition to being individually tinned, marine-grade battery wire is also made with a very high strand count. This keeps it very flexible, which makes it easier to snake through the interior of a boat’s right recesses. It also means it can tolerate excessive vibration and motion better than stiffer cables – and boats on the water are always in constant motion.
So – to recap – you should not use automotive battery wire instead of marine battery cable or wire, especially in marine environments.
If you’re looking for high-quality, flexible, resilient marine battery wire, visit EWCS Wire at EWCSWire.com or contact them at 800-262-1598. They carry a wide range of high-quality electrical conductors, many of which are made in America and offered at great prices.