Hypothetically, why can't we wrap copper wires around car axles and turn them into electromagnets to help charge the batteries?

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Hypothetically, why can&#039;t we wrap copper wires around car axles and turn them into electromagnets to help charge the batteries?

Dayana Doyle · Accepted Answer

Yes. This is how regenerative braking works.There is a style of brakes that is used in many electric or hybrid cars that, rather than converting the motion of the wheels into heat energy the way conventional brakes do, instead convert the motion of the wheels into electrical energy that recharges the car&#039;s battery. By doing this, they can improve the performance of the car and extend how far it is capable of traveling when driven in environments with frequent braking, like most cities.There&#039;s no technical reason why such a braking system couldn&#039;t be installed on a car with a purely internal combustion engine, though I expect that the energy that they produce might be wasted once the battery has been fully recharged, and the extra cost probably isn&#039;t worth the marginally increased battery performance.

lo3ramd · Accepted Answer

This is basically what happens in the alternator. The car&#039;s engine, which turns the wheels, also turns the alternator&#039;s rotor. The magnetic rotor is surrounded by coils of wire, and induces a current that charges the battery. It is important to note, though, that this does take energy from the engine: nothing is for free.

Hypothetically, why can't we wrap copper wires around car axles and turn them into electromagnets to help charge the batteries?

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