Battery 101: Do Cement Floors Ruin Car Batteries?

You may have been told to never put a car battery directly on the floor of the garage because the cement will cause the battery to leak or loose its charge.

…Is this really true? Knowing what we do about batteries and cement it just doesn’t make sense. Or does it? (Fear not – we know the answer.) Let’s explore the myth of car batteries and the garage floor.

Early Car Batteries

If we take a look back at some of the earliest car batteries we will find that they were lead-acid batteries that had glass cells all encased in a wooden box. This means that if they were left on concrete or cement floors, the moisture from the floor could cause the wooden box to wrap, allowing the glass cells to shift and break.

Of course, the battery acid would leak all over the floor and the battery would be rendered useless. Not great.

Evolution

As the construction of the car battery evolved into a nickel-iron battery encased in steel, and then even further with a hard rubber casing, the issue of breaking glass went away – but not the problem with discharging or “leaking”.

The rubber was porous and often contained carbon. The battery shell would take on the moisture of the floor, as with the wooden encasement, creating an electrical current between the battery cells causing them to discharge. Still not great.

Modern Day Batteries

Brands like Trojan and Odyssey are working overtime to continue to innovate battery design to make battery performance and storage better than ever.

The design of modern day batteries includes a hard plastic shell that eliminates the intake of moisture, thus making the garage floor a great place to put your car battery.

Cement and concrete floors provide a fairly good barrier between the car battery and extreme temperature changes that could otherwise cause damage to the battery cells allowing for a discharge leak.

What Does Cause Battery Leaks?

While the garage floor may not be the culprit anymore for leaky batteries there are a few ways your stored batteries can lose their shelf life.

  • Dirt and dust can become carbonized, creating electrical conduction which drains the battery. Combat this by using a clean rag to clean wipe off the tops of the battery.
  • Self-discharge occurs over time with lead-acid batteries. Reactions within the plates happen as the battery ages creating a leak. The warmer the air surrounding the battery the faster the rate of discharge. Keeping the air around stored batteries cool will help slow the rate of self-discharge.
  • While cold temperatures are rarely the cause of battery malfunctions, a battery that is at a low state of charged and exposed to freezing temperatures can freeze causing the case to crack. Keeping your battery fully charged during the winter months is an easy way to prevent this from happening.
  • Knowing the shelf life of your battery can help a lot as well. A car battery stored in a cool and dry place can last a few years if you keep it topped off with a trickle charger.

Today’s batteries are well insulated and no longer take on water that can cause discharging or leaking. That being said, there are clearly right ways and wrong ways when it comes to battery storage. Keeping your batteries clean, dry and understanding their shelf life can make a big difference in preserving their longevity and the quality of their performance. So go ahead and leave that battery on the cool dry floor of your garage. Kinda great, right?