02/25/2021
Your Car’s Battery Health, Especially During a Pandemic
One of the most common issues that we’re seeing during the pandemic, especially in the winter, is automotive battery failures.
The job of the battery is to provide energy to start your car, and to absorb any excess energy produced, by the alternator, that the car doesn’t require.
Why does a battery go dead if a car sits idle for too long? Today’s cars have many onboard computers and modules that have to keep track of memory and time. All items such as clocks, entertainment systems, memory seat presets, theft deterrent systems, and more, all consume small amounts of power while the vehicle is sitting. This is referred to as parasitic draw. This draw will continue until the battery is completely dead.
Cold temperatures reduce the energy reserves that a battery has available to start your car, and in colder weather, it takes more power from your battery to turn the engine over, because the oil is thicker. If your battery is fully charged to 100%, and it is -20C outside, the actual capacity of your battery has been reduced to 80%. An older battery’s energy storage capacity diminishes over time. It’s easy to understand that you can end up with a dead battery after a few days without ever driving the car.
So can a battery be damaged if it goes dead? The answer is YES, since most batteries can be damaged when they are repeatedly allowed to fully discharge. In the winter, a dead battery can actually freeze since the sulfuric acid inside becomes more and more like water when the battery is discharged. Inside the battery are lead plates that are usually suspended in acid, but when the battery is discharge, the plates end up suspended in mostly water. When this water freezes, the ice can crack and warp these plates. Once the plates are warped or cracked, the battery has most likely failed beyond recovery, and on the rare occasion warped plates can short out, and cause the battery to explode.
But what if I’m taking trips to the store during the pandemic, and my battery is still going dead? If your car has been sitting for a few days, the capacity may already be down to 80%, but it’s -20C outside, so the capacity is at 60%. A single start of the engine may draw another 20% or more from the storage of power, leaving you with 40% or less. It may take 30 to 40 minutes of driving to bring that battery back up to a full charge. You leave your house and dive 5 to 10 minutes at a time, perhaps to go grocery shopping. Your battery may have recovered to 60%. Now you come back to the car, and starting it again drops the capacity back to 40%, then you drive home, shut the car off, and leave it for a few more days. That means that the next time you go out to the car, the battery is at 50%.
Battery Tips:
1. Have it tested regularly. At R&R Auto we test every battery any time a car is in for an oil change.
2. Replace it if it fails. Even though the battery may be starting the car, if it fails a test, it will likely leave you stranded when the first really cold day arrives.
3. Replace the battery when it’s old. If your battery is 5 years old, and old battery can fail without warning, and may be causing an extra workload for your charging system, which may also cause premature failure of the alternator.
4. Drive continuously for at least 20-30 minutes every 3 days.
5. If you are taking short trips, extend those trip in order to charge the battery
6. Turn off all accessories when the car is parked, such as heated seats, radio, and the blower fan. These take a lot of energy out of the battery, and people tend to sit with the engine off but these items operating.