Battery Capacity Calculator
Calculate battery capacity, voltage, energy, and performance parameters
Calculate Battery Parameters
Battery nominal voltage
Battery capacity in amp-hours
Stored energy in watt-hours
Battery Analysis Results
Battery Capacity Formula
Common Battery Examples
AA Battery
Voltage: 1.5 V
Capacity: 2.5 Ah
Energy: 3.8 Wh
Alkaline
Car Battery
Voltage: 12 V
Capacity: 50 Ah
Energy: 600.0 Wh
Lead-acid
Smartphone Battery
Voltage: 3.7 V
Capacity: 3 Ah
Energy: 11.1 Wh
Li-ion
Laptop Battery
Voltage: 11.1 V
Capacity: 4.4 Ah
Energy: 48.8 Wh
Li-ion
Power Bank
Voltage: 3.7 V
Capacity: 10 Ah
Energy: 37.0 Wh
Li-ion
Electric Vehicle
Voltage: 400 V
Capacity: 75 Ah
Energy: 30000.0 Wh
Li-ion
Battery Types Guide
Lead-Acid
Voltage: 2V, 6V, 12V
Applications: Cars, backup power
Pros: Low cost, reliable
Lithium-ion
Voltage: 3.7V nominal
Applications: Phones, laptops, EVs
Pros: High energy density
NiMH
Voltage: 1.2V
Applications: Hybrid cars, AA/AAA
Pros: Environmentally friendly
C-Rate Reference
Battery Tips
Higher C-rates reduce total capacity
Temperature affects battery performance
Avoid deep discharge for longer life
Consider safety margins in calculations
Understanding Battery Capacity
Battery Capacity Basics
Battery capacity measures how much electrical energy a battery can store and deliver. It's typically expressed in ampere-hours (Ah) or watt-hours (Wh), indicating how much current can be delivered over time.
Key Relationships
- •Energy (Wh) = Voltage (V) × Capacity (Ah)
- •Discharge Current (A) = C-rate × Capacity (Ah)
- •Runtime (hours) = 1 / C-rate
- •1 Ah = 1000 mAh
Practical Applications
Device Runtime
Calculate how long a device will run on a battery
Charging Time
Estimate charging time based on charger current
Power System Design
Size batteries for solar, UPS, and backup systems
Electric Vehicle Range
Calculate driving range from battery capacity
Example Calculation
Given:
- • Battery: 12V, 100Ah
- • C-rate: 0.2C (5-hour discharge)
- • Load: 20A constant current
Calculate:
- • Energy: 12V × 100Ah = 1200Wh
- • Runtime: 100Ah ÷ 20A = 5 hours
- • Power: 12V × 20A = 240W