1. What is the Battery Capacity Formula?

The battery capacity formula calculates the required ampere-hour (Ah) rating of a battery based on energy demand, system voltage, and accounting for inefficiencies in the system.

2. How Does the Calculator Work?

The calculator uses the battery capacity equation:

Where:

• \( Energy\ Demand \) — Total energy required (watt-hours)
• \( Voltage \) — System voltage (volts)
• \( Inefficiency\ Factor \) — Accounts for losses (typically 1.1-1.3)

Explanation: The equation converts energy demand to charge capacity while accounting for real-world inefficiencies like heat loss and battery aging.

3. Importance of Battery Capacity Calculation

Details: Proper battery sizing ensures sufficient power supply, prevents over-discharge, extends battery life, and optimizes system performance.

4. Using the Calculator

Tips: Enter energy demand in watt-hours, system voltage in volts, and inefficiency factor (1.2 is typical). All values must be positive (energy > 0, voltage > 0, factor ≥ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is a typical inefficiency factor?
A: For lead-acid batteries, 1.2 is common. Lithium batteries might use 1.1. Higher factors provide more safety margin.

Q2: How do I determine my energy demand?
A: Sum the watt-hours of all loads multiplied by their runtime. For example: (10W device × 5 hours) + (50W device × 2 hours) = 150Wh.

Q3: Why is voltage important in the calculation?
A: Battery capacity is measured in amp-hours (Ah), but energy is watt-hours (Wh). Voltage converts between these units (Wh = Ah × V).

Q4: Should I round up the calculated capacity?
A: Yes, always round up to the nearest available battery size to ensure sufficient capacity.

Q5: Does temperature affect battery capacity?
A: Yes, cold temperatures reduce effective capacity. In cold climates, use a higher inefficiency factor (1.3-1.5).