1. What is the Battery Life Equation?

The battery life equation estimates how long a coin cell battery will last based on its capacity, voltage, and the power consumption of the device it powers. This is particularly important for low-power IoT devices and electronics.

2. How Does the Calculator Work?

The calculator uses the battery life equation:

Where:

• \( Capacity \) — Battery capacity in milliamp-hours (mAh)
• \( Voltage \) — Battery nominal voltage in volts (V)
• \( Power \) — Device power consumption in milliwatts (mW)

Explanation: The equation converts the battery's energy capacity (mAh × V) to milliwatt-hours and divides by the device's power draw to get hours of operation.

3. Importance of Battery Life Calculation

Details: Accurate battery life estimation is crucial for product design, determining maintenance intervals, and ensuring reliable operation of battery-powered devices.

4. Using the Calculator

Tips: Enter battery capacity in mAh (typically 10-250mAh for coin cells), voltage in V (typically 3V for lithium coin cells), and device power consumption in mW. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical coin cell capacity?
A: CR2032 lithium coin cells typically have 220-240mAh capacity at moderate discharge rates.

Q2: How does temperature affect battery life?
A: Cold temperatures reduce available capacity, while high temperatures can increase self-discharge.

Q3: Should I consider battery self-discharge?
A: For long-term applications (>1 year), yes. Lithium coin cells self-discharge about 1% per year.

Q4: What's the difference between mAh and mWh?
A: mAh (milliamp-hours) measures charge capacity, while mWh (milliwatt-hours) measures energy capacity (mAh × V).

Q5: How accurate is this calculation?
A: It provides theoretical maximum. Real-world factors like discharge curve, pulse loads, and temperature affect actual life.