Can the battery be charged when the engine is idling?
3 Answers
Yes, the battery can be charged when the engine is idling. When the engine idle is unstable, the first step is to adjust the idle speed. If the issue persists after adjustment, check whether the idle jet and idle air jet are clogged. If the jets are clogged, they can be cleaned with gasoline or acetone and blown through with compressed air. If the jets are not clogged, stabilize the engine speed at a certain level and listen for air leaks at the intake manifold or the middle and lower gasket areas of the carburetor. The car battery, also known as a storage battery, is a type of battery that converts chemical energy into electrical energy. Batteries are categorized into conventional batteries, dry-charged batteries, and maintenance-free batteries. The commonly referred-to car battery is a lead-acid battery, with a normal service life ranging from 1 to 8 years, largely depending on the vehicle's condition.
I've been driving for over ten years, and the battery does charge at idle, but the efficiency isn't high. Idling means the engine runs at low RPM, and the alternator also spins at a lower speed, resulting in less electricity generation and slower charging. Usually, if my battery is running low, starting the car and idling for about ten minutes makes the dashboard indicators appear brighter, which means it's charging. However, if the battery is severely aged, idling might not provide enough charge, and the car could even stall unexpectedly. That's why I now prefer charging while driving, especially after a stretch on the highway—the charging efficiency is higher, and the battery lasts longer. When maintaining the battery, remember to check the alternator's output regularly to avoid overloading it, which could damage the electrical system.
From a technical perspective, when the engine is idling, the battery can be charged, primarily relying on the alternator's operation. However, since the idle speed is relatively low, the alternator's output power is limited. During normal idling, the alternator might only output 20-30 amps of current, whereas it can exceed 50 amps while driving, resulting in significantly slower charging. If the battery itself is in poor condition or there are multiple loads, such as running the air conditioning, the charging efficiency becomes even worse. It's advisable to use a multimeter to check the vehicle's voltage, with an ideal reading around 13-14 volts, to assess the charging status. Avoid prolonged idling for charging as it is detrimental to engine cooling and environmental protection. While it's acceptable for occasional emergencies, making it a habit wastes fuel and accelerates alternator wear. Regularly inspecting wiring and fuses during scheduled maintenance can help prevent issues.
