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🔋 Battery Life Calculator

Calculate battery runtime, required capacity, and power consumption. Analyze battery performance for electronic devices and systems with detailed calculations.

Calculation Type

Input Parameters

Battery Runtime Calculation
Runtime = (Battery Capacity × Efficiency) / Load Current
Calculate how long a battery will last under a given load
%

Results & Analysis

Enter values and click Calculate to see battery analysis results

Battery Technology Guide

Battery Chemistry Comparison

  • Li-ion: 85-95% efficiency, 300-500 cycles
  • Li-Po: 85-95% efficiency, 300-500 cycles
  • NiMH: 70-85% efficiency, 500-1000 cycles
  • Lead Acid: 80-85% efficiency, 200-300 cycles

Key Factors

  • Discharge rate affects capacity
  • Temperature impacts performance
  • Depth of discharge affects lifespan
  • Age reduces effective capacity

HOW TO USE

Select your calculation type (Runtime, Capacity, Power, or Efficiency), enter the known values, and click Calculate to get detailed battery analysis results.

FORMULA USED

Runtime (hrs) = Capacity (Ah) × Efficiency (%) ÷ Load Current (A)
Required Capacity (Ah) = Load Current × Runtime ÷ Efficiency

WORKED EXAMPLE

A 5000mAh battery powering a 250mA device at 95% efficiency will last: (5 Ah × 0.95) ÷ 0.25 = 19 hours.

FREQUENTLY ASKED QUESTIONS

Q: What is C-rate in battery calculations?

A: C-rate is the rate of charge or discharge relative to battery capacity. 1C means the battery fully charges or discharges in 1 hour.

Q: Why does temperature affect battery life?

A: Cold temperatures slow electrochemical reactions, reducing available capacity by 20-40%. Heat accelerates degradation.

Q: What is Depth of Discharge (DoD)?

A: DoD is the percentage of battery capacity used. Limiting DoD to 80% significantly extends battery cycle life.

Q: Which battery chemistry lasts longest?

A: Lithium Iron Phosphate (LiFePO4) offers the most cycles (2000-5000), while Li-ion offers the best energy density.