What is the starting current of an ordinary car?
2 Answers
Generally, the starting current of a car ranges between 100 and 300 amperes. If the engine has a larger displacement, the starting current will correspondingly increase. Here is some additional information: 1. The greater the load on the starter motor, the higher the current output from the battery. The load on the starter motor comes from the compression degree of the piston on the intake air during engine operation. The compression ratio of gasoline engines usually does not exceed 11, while that of diesel engines can reach over 20. Therefore, diesel engines require a higher current when starting. 2. The starting current (CCA) index refers to the minimum current obtainable under specific conditions at -17.8°C and -28.9°C. This index links the starting capability of the battery with important variables such as engine displacement, compression ratio, temperature, starting time, the technical state of the engine and electrical system, and the minimum operating voltage for starting and ignition.
As a seasoned driver with over a decade of experience, I can confidently say that the current value during a regular car's startup is no trivial matter—it typically fluctuates between 400 to 600 amps. This becomes especially noticeable during cold starts, where it can spike above 700 amps, as low temperatures reduce battery efficiency and the starter motor requires higher torque to crank the engine. I learned this the hard way when my car wouldn’t start on a winter morning, only to discover the battery’s CCA (Cold Cranking Amps) was insufficient—a measure of a battery’s cold-weather performance. Now, I maintain my battery regularly, checking its voltage monthly to ensure proper charge and selecting a CCA rating suited to my vehicle (e.g., mid-size sedans often recommend a 600 CCA battery). This not only ensures smooth starts but also prevents roadside breakdowns, enhancing daily driving safety. Remember, high current lasts just seconds, but proper maintenance saves money and hassle.
