Li-ion Voltage Under Load & Runtime: 2RC Cell Model
Wired White v1 Predict Li-ion cell voltage sag, cutoff time and usable capacity under constant, pulse or drive-style loads, with two RC transients and voltage relaxation.
#equivalent circuit
Wired White v1 
Induction Motor Design & Equivalent Circuit Calculator
Wired White v1 Size air-gap, tooth and yoke magnetic loading; calculate motor torque, current, efficiency and losses. Enter circuit parameters or estimate them from catalogue data.
