Information AboutAmpere-hour |
| CATEGORIES ABOUT AMPERE-HOUR | |
| units of electrical charge | |
| non-si metric units | |
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However, in reality, the available capacity of a battery depends on the rate at which it is discharged. If a battery is discharged at a relatively high rate, the available capacity will be lower than expected. Therefore, a battery rated at 100 Ah will deliver 20 A over 5 hours, but if it is instead discharged at 50 A (coulombs per second), it will run out of charge before the theoretically expected 2 hours. For this reason, a battery capacity rating is always related to an expected discharge time, which is typically 5 or 20 hours. The relationship between current, discharge time and capacity is expressed by Peukert's Law . In general, the higher the ampere-hour rating, the longer the battery will last for a certain device. Installing batteries with different Ah ratings will not affect the operation of a device rated for a specific voltage. The Ah rating of a battery is related to, but not the same as, the amount of Energy it stores when fully charged. If two batteries have the same nominal Voltage , then the one with the higher Ah rating stores more energy. It would also typically take longer to recharge. The energy ''E'' available from a battery is approximately given by C V This is only an approximation though, due to the fact that the voltage during discharge is not actually constant. OTHER UNITS The SI unit of electric charge is the Coulomb . One ampere-hour is equal to 3600 coulombs. SEE ALSO |
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