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Battery Capacity Calculator

Battery Capacity Formula:

\[ Capacity (Ah) = Discharge Current (A) \times Time (h) \]

Amps (A)
Hours (h)

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1. What is Battery Capacity?

Battery capacity is a measure of the charge stored in a battery, typically measured in ampere-hours (Ah). It represents how much current a battery can deliver over a specified time period.

2. How Does the Calculator Work?

The calculator uses the battery capacity formula:

\[ Capacity (Ah) = Discharge Current (A) \times Time (h) \]

Where:

Explanation: The formula calculates how much charge the battery can deliver by multiplying the discharge current by the time it can sustain that current.

3. Importance of Capacity Calculation

Details: Knowing battery capacity is essential for designing power systems, estimating runtime, and selecting appropriate batteries for specific applications.

4. Using the Calculator

Tips: Enter discharge current in Amps and time in hours. Both values must be positive numbers. The result will be in ampere-hours (Ah).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between Ah and Wh?
A: Ah (Ampere-hours) measures charge capacity, while Wh (Watt-hours) measures energy capacity. Wh = Ah × Voltage.

Q2: How does temperature affect battery capacity?
A: Capacity typically decreases at lower temperatures and may increase slightly at moderate temperatures above room temperature.

Q3: What is C-rate in batteries?
A: C-rate is the discharge current relative to battery capacity. A 1C rate means discharging at current equal to the Ah rating in 1 hour.

Q4: Why do battery capacities decrease over time?
A: Due to chemical degradation, loss of active materials, and increased internal resistance from charge/discharge cycles.

Q5: How accurate is this calculation for real-world applications?
A: This gives theoretical capacity. Actual capacity may vary based on discharge rate, temperature, age, and battery chemistry.

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