Can I get battery capacity by knowing my need for powering load?

How to Use This Calculator

This calculator determines the required battery capacity (C) in ampere-hours (Ah) based on a modified Peukert's Law. It accounts for the load current (I), discharge time (t), discharge rate (Rc), and includes corrections for non-linear effects in internal resistance at low states of charge (SoC).

To use this calculator:

1. Enter the load current (I) in amperes (A). This is the current your device will draw from the battery.
2. Enter the discharge time (t) in hours. This is how long you want the battery to power your device.
3. Enter the discharge rate (Rc) as a fraction of the nominal capacity. For example, enter 0.1 for 0.1C.
4. Select the battery chemistry from the dropdown menu. Different chemistries have different base and enhanced Peukert exponents (k_base, k_enhanced).
5. Enter the current correction factor (CI) to adjust for experimental discrepancies. Default is 0.1 (10%).
6. Enter the SoC threshold (%) for non-linear effects. Default is 40%.
7. Click "Calculate" to determine the required battery capacity.

The formula used to calculate the battery capacity is:

C = I * t * min(Rc, 1.2)^(1-k) * (1 + CI)

Where:

• C: Required battery capacity in ampere-hours (Ah).
• I: Load current in amperes (A).
• t: Discharge time in hours.
• Rc: Discharge rate as a fraction of the nominal capacity (e.g., 0.1 for 0.1C).
• k: Peukert exponent (base or enhanced, depending on SoC).
• CI: Current correction factor (default = 0.1 or 10%).
• SoC Threshold: State of charge (%) below which non-linear effects occur.

Note: Rc is clamped at 1.2C for discharge rates above 1.2C. The Peukert exponent switches to an enhanced value below the SoC threshold to account for increased internal resistance.