VS - Electrical Systems From Stop-Start to Hybridization

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The capacity is calculated by multiplying the discharge current value by the time required to reach the terminal voltage. For example, a 60Ah battery will deliver a current of 3A for 20 hours before the voltage falls below 10,5V. A few reminders on battery characteristics 0 10 20 30 40 50 60 70 80 90 1 0 10 -30 -20 -10 0 10 20 30 40 Te erature (° ) a acity ( ) Ba tery ca acity de ends on te erature While the battery capacity is nominal at 25°C, it strongly drops at low temperatures. 0 10 20 30 40 50 60 70 80 90 100 110 -30 -20 -10 0 10 20 30 40 Temperature (°C) Battery capacity depends on temperature

Nominal voltage: Conventional lead acid batteries for passenger cars are 12v, although when the battery is fully charged, battery voltage is between 12.8V and 13V. Terminal voltage (V) The terminal voltage is the voltage between battery terminals with load applied. It varies with State of Charge and depends on the electrical load applied. Open-Circuit Voltage (V) The Open-Circuit Voltage is the voltage between battery terminals with no load applied. Battery nominal capacity (Cn) : The capacity in Ah (Ampere-Hour) relates to energy, it measures the total amount of electricity stored in a battery. An Ampere-Hour represents the amount of electricity when a current of 1 Ampere passes for 1 hour. The capacity varies with the rate at which the battery is discharged. The Ampere-Hour Capacity definition of an automotive lead-type battery is the amount of electricity that can be delivered during 20 hours before the voltage falls to 10.50V under standard conditions of temperature (25°C).

Capacity (%)

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