Automotive Battery Storage
The most important consideration when storing any battery is to make sure the voltage never drops below 12.4 volts. Following these simple tips can help extend the life of your battery.
Using a charger. There are two types of maintenance chargers and both will do a great job of maintaining the health of your batteries. The better of the two is a fully automatic multistage or multistep charger, which monitors the battery and charges as necessary. Multistage will charge at varying voltages and varying amperages, depending on what is required. Some of these multistep chargers are also able to work well as a battery charger.
The other is a trickle charger. This is a less expensive and less useful option. As the name suggests, this type of charger simply provides a very light charge, equal to or greater than the charge typically lost while a battery is not in use. Unfortunately, the charge is often more than necessary and can, in fact, result in damaging a battery in the long term. That makes the less expensive option a bit counterproductive if not properly monitored.
If it is not possible to use a maintenance charger, disconnect the battery from the vehicle during storage and leave it clean to prevent the vehicle from discharging the battery. Even the smallest voltage draw, such as a radio and ECM for settings, can kill a battery in the long term.
Always provide a battery with a full charge prior to storage. Then, check the battery voltage every three to six months and charge if it falls below 12.4 volts.
Also, as much as possible, store your battery in a cool, dry location.
The way batteries fade over time is referred to "self-discharge." Due to normal reactions within the battery plates, all lead-acid batteries will lose part of their charge or efficiency over time. The warmer the battery compartment and the older the battery, the higher the rate of self-discharge.
A battery's rate of discharge is only affected by its age, the temperature outside, and the way the inside of the battery is made and its use.
It is common knowledge, in many garages, that a battery cannot be left on a concrete floor and that if this is done, then the battery will be drained by the floor. This is no longer true, for the most part. It was true because battery casings were not built well as well as they are today. Today they are sealed and tightly packaged cells. This is still true, however, if a battery is dirty and the dirt on the battery, which is actually leaking battery acid. Also, if acid is making contact between both posts, and/or the concrete floor the same effect will occur. A new, clean battery will not have this problem. An old or dirty battery will.
Drive safe,
Kevin Gauthier