Battery Care for Classic Cars During Cold Weather

Battery Care for Classic Cars During Cold Weather

Posted by Anderson Restoration Parts on 9th Dec 2022

There are a number of components in a classic car that need to be attended to over the cold winter period, and one of the single most notable here - like with any vehicle - is the battery. Batteries go dead much more often in the winter than during warmer parts of the year, and whether you're storing your classic car or keeping it on the road this cold season, knowing how to protect your battery is important.

At Andersen Restoration Parts, we're happy to help with a huge range of classic car restoration parts and services, including idler arms, suspension kits and much more. We also regularly offer expertise to clients in areas like these - why is winter a different animal than the rest of the year when it comes to battery care, especially if you live somewhere that gets especially cold? Moreover, how can you ensure you classic car battery stays in great shape regardless? Let's dig into this important area before the coldest parts of the year hit.

How Car Batteries Hold a Charge

To lay the proper foundation for this subject, it's important to understand how car batteries hold a charge. The answer here is simple - the chemical reaction between lead and sulfuric acid inside the battery. When this happens, electrons are discharged (or "used"), and these can be replenished by charging - either an external source or from the alternator while your car is running.

These electrolytes are in a liquid form inside the battery, and for that reason, if you've ever seen a car battery before, you'll remember it having a cap. The caps are there to seal off the electrolytes inside from the elements outside (and they can't be sealed perfectly).

As such, there are a few specific factors that will impact the charge your battery holds (beyond the actual number of electrolytes it's capable of holding, of course):

  • Temperature: Heat will cause the electrolytes to evaporate, and cold will increase their viscosity. This has an impact on how much of a charge they can hold. For instance, in a battery at 20°C, the electrolytes will only hold about half the charge they'd hold in a battery at 25°C.
  • Humidity: Some of the water inside can evaporate over time as well, reducing its electrolyte capacity. Many experts suggest that if your battery's been sitting for a while, it may benefit from an electrolyte top-off to ensure its charge capacity is up to par.
  • Local environment: Another factor to take into consideration is your local environment. If you're storing your classic car in a cold, damp garage, for instance, the battery will suffer much more than if it were stored in a warm, dry one.

How Winter Can Impact Car Batteries

As you can see if you combine all the elements in our prior section, you can start to see why winter has such a profound effect on car batteries - especially classic cars.

On the one hand, cold weather reduces the electrolyte's ability to hold a charge, and on the other, it increases their viscosity. The combination of these two effects means that your battery will discharge more quickly in the winter than it otherwise would.

Moreover, if you're storing your classic car for the winter, or only driving it occasionally, then the battery will be at an even higher risk of getting discharged. This makes cold-weather maintenance that much more important than it is during warmer parts of the year.

Considering a Battery Charger

While the primary method of charging a battery comes through natural vehicle operations, winter may present challenges here for some owners. If you don't have a chance to drive your classic car during the winter season, then one option is a battery charger - also sometimes called "trickle chargers."

These devices will keep a small charge on the battery at all times, usually between 0.5 and 2A. This level of charging may not be sufficient for long-term storage (like over the course of several months) but it should be enough to get you by if you just plan on driving your classic car a few times during the cold season.

Additionally, battery chargers are relatively inexpensive compared to the cost of replacing a battery and, when combined with other winter maintenance measures, can help ensure your battery will be ready to go come spring.

Battery Tips for Those Driving Their Classic Cars in Winter

On the flip side, some people choose not to store their classic cars during the winter season and instead drive them as they normally would.

In this case, it's critical to ensure that your battery receives a full charge every time you drive your car - either through regular use or with an external charger if needed. You may also want to consider adding an AGM (Absorbed Glass Mat) battery to your car, as these are more efficient at holding a charge in cold weather than regular lead-acid batteries. Finally, keep an eye on your battery's electrolyte level and top it off if needed. Doing so can help ensure that your classic car is as ready for winter as possible.

As you can see, the winter season presents many challenges for classic car owners, but with the right preparation and maintenance, you can ensure that your battery remains in tip-top shape during even the coldest months of the year. For more on this, or to learn about any of our classic car restoration parts or services, speak to our team at Andersen Restoration Parts today.