1. What is Battery Capacity?

Battery capacity is a measure of the charge stored in a battery, typically expressed in ampere-hours (Ah). It represents how much energy a battery can deliver at a specific voltage over time.

2. How Does the Calculator Work?

The calculator uses the battery capacity formula:

Where:

• \( Energy \) — Total energy in watt-hours (Wh)
• \( Voltage \) — Battery voltage in volts (V)

Explanation: The formula converts energy (in watt-hours) to capacity (in ampere-hours) by accounting for the battery's operating voltage.

3. Importance of Battery Capacity Calculation

Details: Knowing battery capacity is essential for designing power systems, estimating runtime, and comparing different battery types. It helps determine how long a battery can power a device before needing recharge.

4. Using the Calculator

Tips: Enter energy in watt-hours and battery voltage in volts. Both values must be positive numbers. Common battery voltages include 3.7V (Li-ion), 12V (car battery), etc.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between Wh and Ah?
A: Watt-hours measure energy (power × time), while ampere-hours measure charge (current × time). Ah is more useful for battery sizing when voltage is known.

Q2: How do I find my battery's energy in Wh?
A: If only Ah is given, multiply by voltage (Wh = Ah × V). For power tool batteries, check the label (often listed in Wh).

Q3: Why does voltage matter in capacity calculation?
A: Different battery chemistries operate at different voltages. A 3Ah battery at 12V stores more energy than a 3Ah battery at 3.7V.

Q4: Can I use this for any battery type?
A: Yes, the formula works for all battery chemistries (Li-ion, lead-acid, NiMH, etc.) as long as you know the nominal voltage.

Q5: How accurate is this calculation?
A: It provides theoretical capacity. Actual usable capacity may be less due to temperature, discharge rate, and battery age effects.