Why are electric cars able to deliver power instantly, but gas engines take more time to build up power?
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They operate on fundamentally different principles:
As mentioned here the internal combustion engine requires combustion, so we are taking chemical energy, converting to thermal energy, and then the thermal energy is used to PUSH the pistons ( mechanical energy). This process alone takes more time and requires moving parts. The combustion process is rather complicated and the motion of the engine is required to make the process work. The fuel needs ( a mass than needs to me moved) to be sprayed or mixed with the correct amount of air (also a mass then needs to be moved) all inside of the cylinder, the cylinder then need to have a compression stroke to bring this mixture to a critical operating point, before it combusts, the combustion then rapidly expands the “air” (remaining air and the resulting gasses form the combustion) – and physically pushes the piston. In 4 stroke ( typical engines) the piston makes two in-out cycles for each combustion cycle. For a 6 cylinder engine at 500 RPM ( slow by engine standards), we get about 166 “explosions” per MINUTE per cylinder, or 3 per second per cylinder, that is not a very fast way to convert energy.
Conversely – an electric motor, also takes chemical energy, but converts it to electrical energy(in the battery) – and this process is always occurring or ON. This process is very quick and does not involve the moving of a mass. The electrical energy is then converted to mechanical energy in an electric motor. It is basic nature of an electrical motor that it produces torque based on two magnetic fields, so you can have essentially maximum torque (force) as fast as you can create a magnetic field.
A huge benefit here is you can have torque with no moving parts, granted, torque alone is not energy, but essentially max torque ( force) at Zero speed is the key.
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