How long does it take for the car's small lights to drain the battery if left on?
3 Answers
Leaving the car's small lights on for approximately 20 hours can drain the battery. Here's some information about car batteries: 1. Principle: A car battery, also known as a storage battery, works by converting chemical energy into electrical energy. 2. Introduction: It refers to a type of battery that can be recharged and reused after discharge. Common types include lead-acid batteries, nickel-iron batteries, and nickel-cadmium batteries. In lead-acid batteries, the positive electrode is lead dioxide, the negative electrode is lead, and the electrolyte is a dilute sulfuric acid solution. 3. Service life: The lifespan of a car battery depends not only on its structure and quality but also on proper usage and maintenance. Typically, car batteries last about 2 years.
I've researched this issue before. The small lights on a car usually indicate the parking lights or side lights, which don't consume much power. A single light is about 5-10 watts, so together they add up to 10-20 watts. From my experience, a new battery, like one with a capacity of 60 ampere-hours, can theoretically last 30 to 50 hours. However, in reality, a battery cannot be fully discharged. Older batteries or those with corrosion issues may last even shorter, possibly failing after just 24 hours. I once drove an older model car and forgot to turn off the small lights while camping. The next morning, the car wouldn't start, and I had to spend money on a rescue service. Prevention is simple: develop the habit of checking before leaving the car, or install an automatic delayed light-off device. Not only is replacing a depleted battery expensive, but it can also reduce the lifespan of the starter motor. So, I recommend keeping a car jump starter for emergencies.
This is a very common issue, and I've heard many cases. Small lights don't consume as much power as headlights, but if left on continuously, they can drain about one-tenth of the battery's charge overnight. Under normal circumstances, a new battery can last a day or so without much trouble, but with an aging battery or in cold weather, the power drains faster, and it can be completely depleted in just a dozen hours. I once forgot to turn off the lights on a rainy day, and the battery quickly deteriorated, making it difficult to start the next day—I had to push-start the car. To avoid this, you can buy a small light reminder sticker for your car; it's cheap and practical. A dead battery isn't just about spending money on a replacement—it also affects the vehicle's entire electrical system. Regular maintenance can save a lot of hassle.
