Why Can’t Electric Cars Charge Themselves?

The rise of electric cars has been a surprisingly long process.

The electric car was actually first seen being practically used 20 years before the first Model T, but they quickly fell out of fashion due to the emergence of combustion engines that could propel a car much faster than their electric counterparts.

However, these types of vehicles have had somewhat of a resurgence in the modern day, as the technology around them has improved significantly, and now they can hold up against the big boys.

This renewal of interest in electric cars came about due to the advancement of battery technology and the environmental problems that combustion engines cause.

Yet, there is still one issue that the manufacturers of electric cars have been unable to solve. It has eluded most engineers and designers, practically making them pull their hair out in frustration.

Electric cars cannot charge themselves. We know combustion engines can, it is something that most people who own standard cars don’t have to worry about, the battery will just be charged while they drive. But that is not the case for electric cars, so why is that?

Why can’t electric cars charge themselves? In this article, we seek to answer that question and explain to you why electric cars can’t drive themselves.

So, Why Can’t They Charge Themselves?

Simply, it’s to do with the makeup of the energy itself. In a combustion car, there is normally something called an alternator.

An alternator is an electrical generator that converts mechanical energy into electrical energy in the form of a current that is alternating, which is then fed back into the battery thus charging it.

Since mechanical energy needs kinetic energy – energy generated by movement – and potential energy – energy produced by stresses within an object (like elasticity), objects position to other objects (like the tides and the moon), or other factors, the alternator is made of a rotating magnet around a stationary armature to create that energy, very similar to how the sun rotates around the earth.

In a combustion car, the battery provides the electricity that starts the combustion engine, the combustion of the engine then provides mechanical energy to the alternator, and the alternator produces electrical power which goes back to the battery, replacing that which was lost.

The only thing that needs to be added is fossil fuel to keep the car running, as the fuel is the only energy source that cannot be reproduced through energy conversion.

However, in an electric car the energy is solely produced from the battery itself.

Without a secondary energy source, it is pointless to try and use an alternator to produce more electricity, as the alternator would require electricity from the battery to produce mechanical energy to convert back into electricity.

This would drain far more energy than could ever be produced by the alternator and so your car would be dead before it started.

This is a problem which has haunted electric car manufacturers for years and in the years before now, no one really had any answers on how to solve this other than ‘only take short trips, so your battery doesn’t die’.

Still, engineers, designers, and manufacturers have not given up and have managed to come up with some ideas about how to solve the problem.

Electric Cars: Self Charging Potential

Regenerative Braking

This is an ingenious idea that is being used solely in electric cars currently, but it has far-reaching potential.

The basic premise is that the secondary energy source that you would need to restore energy to the battery can be gained from the kinetic energy of the moving car itself.

The car is fitted with a regenerative-hydraulic hybrid braking system which provides two levels of braking: the generator mode and the pure brake mode.

When you press on the brake of your electric car, the generator mode is engaged and the kinetic energy produced by the rotation of the wheels is transferred through a drivetrain to a generator.

The generator is activated and some of the kinetic energy is converted to electrical energy and stored in the battery. If the generator mode is not enough to slow down or stop the car, then the system switches to pure braking mode instead, making sure the car will stop.

This happens normally after a certain amount of pressure is applied to the brake. Thanks to this system, electric cars can regain some energy to keep their batteries going, but it is not enough to completely restore the battery and will only prolong the time before the car needs to be charged.

However, it is still an amazing way to keep your car going with a combustion engine.

Solar Panels

This idea was more of an ethereal concept, something that we thought possible but never dreamed anyone would do.

That was until a European manufacturer and a European designer got together and came up with the ‘Lightyear’, a totally solar-powered car that was based on previous solar-powered cars used for short term competitions.

However, with the Lightyear, its self-charging capacity has been improved to the point where it can be used every day.

The solar panels that power the car are contained under a thick safety glass for protection and, while the cells are in use, charge the battery up to 7 miles of distance for every hour charging.

While this is a feat of engineering, at the moment that means the car can only really be used for short trips every day, rather than long journeys, but since this is a starting point for solar-powered cars it has an insane amount of potential.  

Passive Charging

Passive charging is more of a concept than an actual practical solution to the problems of a self-charging electric car.

But, even in its base form there are some interesting ideas on how to engineer a way to passively charge a car, and someone may come along in a few years with a viable way to achieve it.

Induction Charging

Induction or wireless charging only really appeared on the market a few years ago, but since then it has become a staple in households or in shops as a convenient way to charge your portable devices.

The charging is done by using electromagnetic induction to create electricity through a charging coil that is transferred to the device through a receiving coil. The electrical current moves through the device from one coil to the other and is collected by the battery, thus charging it.

The basic idea could work for an electric car, but the concern lies in the infrastructure needed to create such a large field for the electricity to transfer between.

However, it currently works for all manner of household objects, from smartphones to toothbrushes, so who’s to say that this type of charging will not appear at gas stations in the next few years.

Final Thoughts

The problems with self-charging in electric cars will not go away overnight, but people have been coming up with ever more ingenious solutions to this problem as the years go on.

We are now at the point where a self-charging electric car is right at the end of our fingertips and the potential solutions you see in this article could be the actual solutions of tomorrow.