RC TORQUEHOUSE / POWER, MADE VISIBLE

Battery lab

Build a standard LiPo pack from 2S to 6S, then trace its nominal voltage and energy through an RC power path. The values are deliberate idealizations—not an upgrade recommendation or a speed, heat, current or runtime prediction.

01 / PACK BUILDER

Series cells add voltage

Check the actual label and manual. Before any pack-voltage change, confirm the exact ESC, motor, chassis, battery, charger and connector all support it. Follow the manufacturer’s charging instructions and never leave charging unattended; this is not charge setup advice.

2S7.4 V nominal8.4 V full-charge maximum
Nominal energy37.0 Whnominal V × Ah
Ideal unloaded motor RPM23,680Kv × nominal V
Fixed-current illustration296 W7.4 V × assumed 40 A

Standard LiPo model only: each series cell is treated as 3.7 V nominal and 4.2 V at full-charge maximum. Series count changes voltage; it does not change the mAh value shown for the series string. Nominal watt-hours are a label-level energy estimate. A Horizon example computes a 6S 3200 mAh pack as 71.04 Wh from 22.2 V × 3.2 Ah. Source.

02 / POWER FLOW

Battery → ESC → motor → gears → tyres

BATTERYvoltage source
ESCswitches and controls
MOTORelectrical → rotation
GEARSratio changes speed/torque
TYREScontact with surface

Static power path. Play is optional and illustrative.

Moving from 2S to 4S doubles this model’s nominal voltage, and Kv × voltage doubles the ideal unloaded RPM. It does not automatically double usable power, speed, current or runtime. Load, ESC control, motor efficiency, gearing, tyres, battery voltage sag and heat change the outcome. The optional watts card holds current fixed only to demonstrate P = V × I; the same current is not guaranteed in a real vehicle.

03 / SAFETY BOUNDARY

The calculation stops at the workbench

Charge the labelled cell count. The Spektrum/E-flite guide says to set the charger to the pack label’s cell count/voltage and warns that a different selection can cause fire.

4.2 V is a maximum, not a target to exceed. That guide says LiPo cells should never be charged above 4.2 V per cell.

Do not generalize C-ratings. This lab intentionally does not turn a C number into a performance claim; pack condition, wiring, connectors, load and manufacturer limits all matter.

Read the manufacturer guide for its full charging, inspection, damaged-pack and disposal guidance. Stop and use the exact manual if pack, charger, connector or voltage compatibility is unclear.