A vehicle's battery is as important as any other part under the hood, since so many of those other parts are powered by the battery itself! If your car's battery is underpowered, you may know that your vehicle may not start in the morning, but this can also lead to the car simply shutting down while you're driving. To ensure this never happens to you, note a few basic questions you might have about automotive batteries and their overall maintenance and upkeep, and remember to have your own vehicle's battery checked often, so you know it's always in good working condition.
Can a battery freeze? Why doesn't it recharge on a cold morning?
Most automotive batteries in use today no longer require you to refill them with water; however, batteries still have water inside them, as well as sulphuric acid, and both of these liquids can freeze. These liquids are needed to conduct an electrical charge throughout the battery, so if they're frozen, the battery will be dead and you typically cannot recharge it.
If this happens, note that you don't necessarily need to replace the battery. Letting it get warm will usually allow those liquids to thaw, and you can then usually recharge the battery as needed.
Why does driving short distances drain the battery?
A vehicle's alternator will recharge that battery after the car has started, but not necessarily to full power, and of course this doesn't mean the battery will stay recharged either! As said, many parts under the hood run on electrical power, so the battery continues to drain as you continue to operate the car. The alternator doesn't necessarily recharge the battery as quickly as it drains, but needs more time to restore power to the battery. Short commutes may not give the alternator that time it needs to recharge the battery fully, so if you only drive a short distance every day, you might want to be prepared to replace the battery more often than usual.
Can you recharge a car battery from a car battery?
A car battery is not typically strong enough to recharge another battery, without the first battery being hooked to an alternator. The power it takes to recharge an automotive battery is usually more than what is stored in the battery itself, which is why you always want to have a vehicle running when you jumpstart another car. The alternator of the powering vehicle should then keep its battery strong enough and charged enough to start the second battery, without having both batteries fail!