Calculator Form
Formula Used
Output voltage: Vout = √(Watts × Coil resistance)
Output current: Iout = √(Watts ÷ Coil resistance)
Loaded cell voltage: Vloaded = Cutoff voltage − Voltage sag
Pack low voltage: Vpack = Series cells × Vloaded
Pack input current: Ipack = Watts ÷ (Vpack × Efficiency)
Current per cell: Icell = Ipack ÷ Parallel groups
Usable current limit: Iusable = CDR × Age factor × Headroom factor
Maximum safe watts: Wsafe = Iusable × Parallel groups × Vpack × Efficiency
Pack energy: Wh = Series cells × Parallel groups × Ah × Nominal voltage × Age factor
Estimated puffs: Puffs = Wh ÷ (Watts × Puff seconds ÷ 3600)
How To Use This Calculator
Enter your selected wattage and coil resistance first.
Add your battery layout, capacity, voltage, and CDR rating.
Use a realistic cutoff voltage and voltage sag value.
Set efficiency based on your device board estimate.
Add headroom and age derating for a safer margin.
Press the calculate button to view current and runtime results.
Use CSV or PDF buttons to save the calculation.
Example Data Table
| Watts | Resistance | Cells | Efficiency | CDR | Estimated Result |
|---|---|---|---|---|---|
| 60 W | 0.30 Ω | 2S1P | 90% | 20 A | Moderate current demand |
| 100 W | 0.18 Ω | 2S1P | 88% | 25 A | Higher battery load |
| 45 W | 0.50 Ω | 1S2P | 90% | 15 A | Shared parallel current |
Regulated Mod Battery Guide
Why Battery Demand Matters
A regulated mod changes battery power into controlled output power. It tries to hold the selected wattage while the cell voltage falls. That control feels steady, but it also means battery current rises near the lower cutoff. A safe estimate should use the lowest loaded cell voltage, not only a fresh charge.
What This Calculator Checks
This calculator estimates input current, output current, runtime, and safe wattage. It supports series and parallel battery layouts. It also includes efficiency, voltage sag, age derating, current headroom, and device output limits. These inputs make the result more practical than a simple watts divided by volts check.
Series And Parallel Layouts
Cells in series increase pack voltage. Current through each series cell stays the same. Cells in parallel increase available capacity and share current. A two cell series mod has more voltage headroom. A parallel layout can reduce current per cell. Many regulated devices use series cells, so each cell must handle the calculated pack current.
Runtime Planning
Runtime is based on watt hours. The calculator converts cell capacity into pack energy. It then compares that energy with selected wattage and puff time. The result is an estimate, not a promise. Real runtime changes with coil heat, screen use, board losses, temperature, cell age, and cutoff behavior.
Safety Margin
The continuous discharge rating is a useful reference. Still, it should not be treated as a target. A margin helps cover heat, weak cells, and measurement error. The calculator lowers the usable current by your headroom and age derating values. If the estimated current is above that limit, choose lower watts or stronger suitable cells.
Better Input Habits
Use honest values. Enter the wattage you actually plan to use. Use the coil resistance installed on the device. Use the lowest expected loaded cell voltage. Use the real rating from the cell maker, not a wrap claim. Matched married cells are best for multi cell devices.
Final Note
This tool helps with planning and comparison. It is not a substitute for device manuals, charger safety, or battery knowledge. Stop using any cell that is damaged, hot, dented, torn, wet, or behaving strangely. Safe limits matter more than bigger numbers during every session.
FAQs
What is a regulated mod battery calculator?
It estimates battery current, runtime, output voltage, and safe wattage for regulated devices. It helps compare selected watts against battery limits.
Why does current rise as voltage drops?
A regulated board tries to maintain wattage. When battery voltage gets lower, the board must draw more current to supply the same output power.
What is CDR?
CDR means continuous discharge rating. It is the current a cell is rated to provide continuously under proper conditions.
Should I use pulse ratings?
Use continuous ratings for planning. Pulse ratings vary by seller and test method. They can create unsafe assumptions.
Why include board efficiency?
No regulated board is perfect. Some battery energy becomes heat. Lower efficiency means more battery current is needed for the same wattage.
What does voltage sag mean?
Voltage sag is the temporary voltage drop under load. It increases current demand and reduces usable runtime.
Can this calculator replace battery safety knowledge?
No. It is only an estimating tool. Always follow device instructions, cell ratings, charger guidance, and safe battery handling.
Why use safety headroom?
Headroom reduces the usable current target. It helps cover heat, aging, mismatch, sag, and input errors.