Battery care basics, brought to you by Battery Tender

Battery care basics, brought to you by Battery Tender

Whether storing a vehicle for months or even a couple of weeks, battery care is important to make sure the car will start when you need it to. Surprisingly, this can be the case even with new or fully charged batteries. Batteries can lose charge over time, and this is especially true in modern cars.

“If your vehicle is not a daily driver or is going to be stored long-term, a Battery Tender® battery charger will maintain a proper state of charge as well as prevent damage to the battery from over-charging,” explains Battery Tender Vice President of Engineering, Peter Shread. “Modern vehicles have active electronics that constantly draw current. We have measured up to 200mA of current draw from a vehicle’s battery even when that vehicle is powered ‘off.’”

Even in a racecar with a full power disconnect switch, a battery can lose charge over time. That may leave you without sufficient power to start the vehicle, and even if it does fire up, it could hamper performance. This is especially true for racecars without charging systems, but also for cars with onboard alternators.

“We have observed some charging systems that are not able to provide the instantaneous current source for the discharge of a spark plug,” says Shread. “In these charging systems, the additional current needed is drawn from the battery. If the battery is not sufficiently charged or in a poor state of health, it may not be able to supply the current required. This can lead to engine misfires or stalls.

“Also, if the battery is at the end of its lifetime and unable to hold a charge or otherwise damaged, that could impact performance. Modern vehicle charging systems are designed around the constant load and filtering that a battery presents. This will show as unwanted behavior in the electronics and even a check engine light on street vehicles.”

Racers with formula cars and sports racers that don’t have alternators are well aware of the need to charge the battery after every session, but for those with road car-based race cars or track toys, the necessity of maintaining the battery is less obvious. Shread says that even for cars driven several times a month, if they’re sitting in between drives, the batteries should be maintained on a Battery Tender battery charger.

That goes for a new battery as well. If you’ve bought a battery that isn’t going to be used for a while, hooking it up to a Battery Tender battery charger will ensure it is ready when it’s time for the battery to be hooked up and used.

“If you’re storing a new battery, absolutely connect to a Battery Tender battery charger,” he says. “And if you’re installing that new battery directly into a vehicle, it is generally recommended to charge up the battery first on a Battery Tender battery charger.  Refer to the battery manufacturer’s user manual or instructions.”

Next, we’ll take a look at how to choose and use a battery maintainer.

Visit to learn more about their world-class power products.