What is the starting current for a car engine?
2 Answers
When starting a gasoline engine, the battery output current can reach 200 to 600 amps, while for a diesel engine, it can go up to 1000 amps. Different engines are paired with different starters, and car starters typically have a power rating between 1 kilowatt and 3 kilowatts. During engine startup, the battery releases a very high current to ensure smooth engine ignition. Here are some key points about starting current: 1. The starting current refers to the minimum current achievable under specific conditions at -17.8°C and -28.9°C. This metric links the battery's starting capability to important variables such as engine displacement, compression ratio, temperature, starting time, the technical condition of the engine and electrical system, and the minimum operating voltage for starting and ignition. 2. Generally, the starting current is about 20 times the operating current. After driving 25 kilometers, it is advisable to test the battery voltage. For a 48V battery, a reading around 50V indicates normal battery condition.
I remember my family sedan draws around 200 amps during startup, and that's during summer at normal temperatures. There's quite a variation between vehicles - my friend's 3.0L SUV requires over 300 amps for cold starts. Temperature makes a huge difference too. Last winter at -10°C, my car's starting current suddenly jumped to 280 amps. Let me emphasize about car batteries - as they age, increased internal resistance prevents delivering sufficient instant current. That's exactly why my battery died and left me stranded last time. I recommend everyone check the CCA parameter with professional equipment before winter each year, as this value truly reflects a battery's starting capability. For those with modified vehicles, extra caution is needed - high-power audio system modifications can significantly reduce your starting current margin.
