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Battery Capacity Equations:
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Battery capacity is a measure of the charge stored by the battery, determined by the mass of active material contained in the battery. It represents the maximum amount of energy that can be extracted from the battery under certain conditions.
The calculator uses two fundamental equations:
Where:
Explanation: The first equation calculates the capacitance in farads, while the second converts charge in coulombs to the more practical ampere-hour unit commonly used for batteries.
Details: Knowing a battery's capacity is essential for determining how long it can power a device, comparing different batteries, and designing electrical systems with appropriate power sources.
Tips: Enter the total charge in coulombs and the voltage in volts. Both values must be positive numbers. The calculator will provide the capacity in both farads and ampere-hours.
Q1: What's the difference between farads and ampere-hours?
A: Farads measure capacitance (ability to store electrical energy), while ampere-hours measure charge capacity (total amount of charge a battery can deliver).
Q2: Why is 3600 used in the Ah calculation?
A: 3600 seconds = 1 hour, and since 1 ampere = 1 coulomb/second, we divide by 3600 to convert from coulombs to ampere-hours.
Q3: What are typical battery capacities?
A: Small batteries might be 0.5-3 Ah, car batteries 40-100 Ah, while large industrial batteries can be hundreds of Ah.
Q4: Does voltage affect battery capacity?
A: Voltage doesn't change the total charge (Q), but higher voltage batteries can deliver more power (P = VI) for the same current.
Q5: How does temperature affect capacity?
A: Capacity typically decreases at lower temperatures due to slower chemical reactions in the battery.