Capacitance to mAh Calculator
Convert electrical capacitance to equivalent battery capacity in milliamp-hours (mAh). Compute the stored charge in Farads and voltage to analyze supercapacitors and energy storage devices with instant results.
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Capacitance to mAh Calculator
mAh = (Capacitance × Voltage × 1000) ÷ 3600
This conversion estimates equivalent battery capacity using stored charge. Actual battery performance depends on discharge characteristics and efficiency.
How to Use Capacitance to mAh Calculator
Determining the equivalent battery capacity in milliamp-hours from a capacitor is a key step in evaluating supercapacitors for power backup and energy storage setups. This tool makes the conversion process quick by automating unit scaling and equations. Follow these numbered steps to calculate the capacity:
- Step 1: Enter capacitance value. Input the physical capacitance rating of your component. For example, enter 50 for a standard supercapacitor rating.
- Step 2: Select capacitance unit. Choose the appropriate unit from the dropdown. The options include Farad (F), Millifarad (mF), or Microfarad (µF).
- Step 3: Enter voltage. Input the active operating voltage across the capacitor plates.
- Step 4: Select voltage unit. Choose Volt (V) or Millivolt (mV) depending on your application measurements.
- Step 5: Click Calculate. Select the Calculate button to compute the results. The system will convert your input values into base SI units and evaluate the stored charge.
- Step 6: Read equivalent battery capacity in mAh. The output shows the total charge in Coulombs, the converted mAh value, and equivalent voltage and capacitance.
This tool performs a theoretical calculation to help design engineers compare capacitor charge storage directly against standard rechargeable battery ratings. It is particularly useful when choosing supercapacitors for low-power microcontroller backup power, solar energy harvesting circuits, or automotive memory storage modules.
How to Calculate Capacitance to mAh
Calculating the battery capacity equivalent of a capacitor requires finding the total stored charge in coulombs and converting it to milliamp-hours. Use the following equations for manual calculations:
Capacitance to mAh Conversion Formulas
Charge equation:
Milliamp-hour conversion:
Since one coulomb represents one ampere-second, dividing the charge in coulombs by 3.6 directly yields the value in milliamp-hours:
Where:
- Capacitance: Stored capacity measured in Farads (F).
- Voltage: Potential difference across the plates measured in Volts (V).
- Charge: Electrical charge quantity in Coulombs (C).
- mAh: Equivalent capacity rating in milliamp-hours.
Real-Life Example Calculation
Let us analyze a supercapacitor rated at 50 Farads operating at 12 Volts to determine its equivalent battery capacity in mAh.
Step 1: Calculate the stored charge in Coulombs
Multiply the capacitance value by the operating voltage:
Charge = 50 F × 12 V
Charge = 600 Coulombs
Step 2: Convert the stored charge to milliamp-hours
Scale the charge value by multiplying by 1000 to convert to milliamperes, and then divide by 3600 seconds in an hour:
mAh = (600 × 1000) ÷ 3600
mAh = 600,000 ÷ 3600
mAh = 166.67 mAh
Final Answer:
The 50 F capacitor at 12 V stores a total electric charge equivalent to approximately 166.67 mAh.
Capacitance to mAh Chart
This reference chart displays the electrical charge in Coulombs and equivalent battery capacity in mAh for common supercapacitor ratings at standard operating voltages. All values are calculated using the verified equation mAh = (Capacitance × Voltage × 1000) ÷ 3600.
| Capacitance (F) | Voltage (V) | Charge (C) | Equivalent Capacity (mAh) |
|---|---|---|---|
| 1 F | 5 V | 5 C | 1.39 mAh |
| 5 F | 5 V | 25 C | 6.94 mAh |
| 10 F | 12 V | 120 C | 33.33 mAh |
| 25 F | 12 V | 300 C | 83.33 mAh |
| 50 F | 12 V | 600 C | 166.67 mAh |
| 100 F | 5 V | 500 C | 138.89 mAh |
| 100 F | 12 V | 1200 C | 333.33 mAh |
| 500 F | 2.7 V | 1350 C | 375.00 mAh |
Note: These values are theoretical charge equivalents. Actual battery discharge performance is influenced by circuit design, discharge rate efficiency, and minimal voltage cutoffs.
Capacitance to mAh Frequently Asked Questions
Yes, electrical capacitance in farads can be converted to battery capacity in milliamp-hours (mAh) if the operating voltage is known. Capacitance represents the charge stored per volt, while mAh represents total electric charge. The conversion calculates total charge in coulombs (farads multiplied by volts) and then converts coulombs to mAh by dividing by 3.6.
The equivalent capacity in mAh of a 1 farad capacitor depends entirely on the voltage applied to it. For example, at a voltage of 5 volts, a 1 farad capacitor holds 5 coulombs of charge, which is equivalent to approximately 1.39 mAh. If the voltage is increased to 12 volts, the stored charge becomes 12 coulombs, equivalent to 3.33 mAh.
No, capacitor capacity and battery capacity operate on different physical principles. A capacitor stores electrical energy electrostatically in an electric field, allowing rapid charging and discharging with low energy density. A battery stores energy chemically, providing high energy density and stable voltage discharge curves over a longer duration.
Supercapacitors have higher power density, can handle millions of charge-discharge cycles, and charge almost instantly, but store far less energy per unit volume than batteries. Batteries have high energy density, allowing them to power devices for hours, but they degrade over a few thousand cycles and take longer to charge.
Voltage is required because capacitance only defines how much electric charge a capacitor can hold per volt. The actual stored charge (in coulombs) is the product of capacitance and the operating voltage. Because milliamp-hours represent a unit of absolute electric charge, you must multiply the capacitance by the voltage to calculate the equivalent mAh rating.
The formula to convert capacitance to equivalent battery capacity is mAh = (Capacitance in Farads × Voltage in Volts × 1000) ÷ 3600. This is simplified to mAh = (Capacitance × Voltage) ÷ 3.6. First, multiply capacitance by voltage to find the charge in coulombs, then scale it to milliamp-hours by dividing by the conversion factor of 3.6.