1. What is the DigiKey Battery Life Calculator?

The DigiKey Battery Life Calculator estimates how long a battery will last based on its capacity and the current draw of the device it powers. It's a simple but essential tool for electronics design and power management.

2. How Does the Calculator Work?

The calculator uses the basic battery life equation:

Where:

• \( \text{Battery Capacity} \) — The energy storage capacity of the battery in milliamp-hours (mAh)
• \( \text{Device Current Draw} \) — The current consumption of the device in milliamps (mA)

Explanation: The equation divides the total available charge (mAh) by the rate of consumption (mA) to determine how many hours the battery will last.

3. Importance of Battery Life Calculation

Details: Accurate battery life estimation is crucial for designing portable electronics, IoT devices, and any battery-powered system to ensure adequate runtime between charges or replacements.

4. Using the Calculator

Tips: Enter battery capacity in mAh (found on battery specifications) and device current draw in mA (measured or from device specifications). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Is this calculation accurate for all battery types?
A: This provides a theoretical maximum. Real-world results vary due to factors like battery age, temperature, discharge rate, and circuit efficiency.

Q2: How do I account for intermittent device usage?
A: For devices that cycle between active and sleep modes, calculate average current draw by weighting each mode's current by its duration.

Q3: What if my device uses different voltages than the battery?
A: This calculator assumes the battery voltage matches the device requirements. For voltage conversions, you'll need to consider power (mWh) instead.

Q4: How does battery capacity change with discharge rate?
A: Some batteries (especially alkaline) have reduced capacity at higher discharge rates. Check the battery's datasheet for rate-dependent capacity.

Q5: Should I derate the calculated battery life?
A: It's often wise to multiply the result by 0.7-0.8 to account for real-world conditions and battery aging.