ELECTRIC VEHICLE MOTOR, BATTERY & RANGE CALCULATOR

Motor Design

Enter the geometry, materials, and winding of a permanent-magnet motor (BLDC or PMSM) and the tool computes the achievable torque, power, back-EMF, and rated voltage/current for that design. This validates a motor you already have in mind rather than designing one for you — pick D/L/air-gap/turns and see what they can deliver. Supported topologies are permanent-magnet only (BLDC/PMSM); induction, switched-reluctance, and axial-flux motors use different physics and are not modeled here.

Type:

motor topology

Cooling:

sets the default current density below

Core steel:

lamination steel grade (core loss + density)

Magnet:

rotor magnet grade (remanence + temp behavior)

pole pairs

rated mechanical speed, rpm

stator bore diameter, mm

stack length, mm

mechanical air gap, mm

k_C:

Carter's coefficient (slotting correction), fixed typical value

h_m:

magnet thickness, mm

series turns per phase

k_w:

winding factor

α_PM:

magnet arc coverage ratio

A_wire:

wire cross-section area, mm²

current density, A/mm² (default follows cooling class)

T_op:

magnet operating temperature, °C

P_target:

target power, W — informational, compared against P achieved below

k_peak:

short-burst overload ratio vs. continuous power

Motor Results

τ_p:

pole pitch, mm

B_gap:

air-gap flux density, T

B_r:

magnet remanence, temp-derated, T

Φ_m:

peak flux per pole, mWb

ψ_f:

flux linkage per phase, mWb

electrical frequency, Hz

E_ph:

back-EMF per phase (RMS), V

V_line:

rated line-to-line voltage, V — feeds battery pack sizing below

K_t:

torque constant, N·m/A

K_e:

back-EMF constant, V·s/rad

I_rated:

rated RMS phase current, A

achieved torque, N·m

achieved continuous power, W

P_peak:

achieved peak power, W

P_core:

core loss estimate, W — informational only

m_motor:

active + housing mass estimate, kg

Margin:

% power margin vs. cruise demand (see Range section) — negative means undersized

Battery Pack Design

Pick a cell chemistry and specs, and a target pack size. Series cell count is derived from the motor's rated voltage above; parallel string count is sized for whichever is larger of your target energy, the motor's continuous current draw, or its peak/burst draw — you don't need to re-enter the motor's voltage or current here.

Chemistry:

sets the cell defaults below

V_nom:

cell nominal voltage, V

V_max:

cell full-charge voltage, V

V_min:

cell cutoff voltage, V

Ah:

cell rated capacity, Ah

R_cell:

cell internal resistance, mΩ

C_cont:

continuous discharge C-rate

C_peak:

peak/burst discharge C-rate

E_target:

target pack energy, kWh

DoD:

usable depth-of-discharge fraction

k_pack:

cell-to-pack packaging efficiency (BMS/cooling/structure overhead)

Wh/kg:

cell-level gravimetric energy density, Wh/kg

η_ctrl:

motor controller/inverter efficiency — also used in Range below

Battery Results

N_s:

series cell count

N_p:

parallel string count

Cells:

total cell count

V_nom:

pack nominal voltage, V

V_max:

pack full-charge voltage, V

V_min:

pack cutoff voltage, V

Ah:

pack capacity, Ah

Wh:

pack nameplate energy, Wh

Wh_usable:

usable energy after DoD + packaging losses, Wh — feeds Range below

R_pack:

pack internal resistance, mΩ

I_cont,req:

continuous current the motor demands, A

I_peak,req:

peak current the motor demands, A

I_cont,max:

pack's continuous current capability, A

I_peak,max:

pack's peak current capability, A

V_sag:

voltage sag at peak current, V

V_term:

worst-case terminal voltage at peak current, V

m_pack:

pack mass estimate, kg

Range Estimate

Vehicle mass here is added to the motor and battery masses computed above automatically. A flat-road, constant-speed cruise is assumed; the EPA-style correction factor and city-driving regen credit turn the theoretical physics-model range into a more realistic estimate.

m_chassis:

vehicle mass excluding motor and battery pack, kg

C_d:

aerodynamic drag coefficient

frontal area, m²

C_rr:

rolling resistance coefficient

cruise speed, km/h

η_batt:

battery discharge efficiency

η_motor:

motor efficiency at cruise load

η_gear:

gearbox/final-drive efficiency

Profile:

city profile applies the regen credit below

k_EPA:

realism correction vs. theoretical physics-model range

k_regen:

range multiplier from regenerative braking, city profile only

Range Results

m_total:

total vehicle mass (chassis + motor + pack), kg

F_roll:

rolling resistance force, N

F_aero:

aerodynamic drag force, N

F_total:

total road-load force at cruise, N

P_wheels:

power demand at cruise, W

η_total:

combined battery-to-wheel efficiency

Wh/km:

energy consumption, Wh/km

Range_theo:

theoretical physics-model range, km

Range:

realistic range after EPA-style correction + regen credit, km