Today, electric vehicles are in a booming period, with global BEV sales increasing by 68% year-on-year in 2022. The popularity of electric vehicles is mainly due to the world's efforts to reduce the negative impact of humans on the environment and seek a more sustainable energy supply.
An average fuel vehicle can emit about 4.6 tons of carbon dioxide into the atmosphere every year, while a pure electric vehicle does not directly emit greenhouse gases. However, the cleanliness of an electric vehicle depends on the source of electricity.
For example, about 61% of electricity in the U.S. was generated by fossil fuels in 2021, and using electric vehicles there is not necessarily clean.
The mechanics of an electric vehicle are simpler than that of a gasoline vehicle.
This is because it is powered by an electric motor and is not propelled by an internal combustion engine like a regular car. One of the advantages of an electric motor over an internal combustion engine is that it can output a high torque (i.e., the power of rotation) regardless of the speed. With it to drive the car, there is no longer a need for a complex gearbox.
At present, electric vehicles can be divided into two categories: pure electric vehicles and hybrid electric vehicles.
The latter has both an internal combustion engine as well as a battery and an electric motor. Some hybrid vehicles use an internal combustion engine to drive a generator, while BEVs only have an electric motor to charge the battery, and when the battery is depleted, it is connected to an external power source to charge.
Today, most electric vehicles use lithium-ion batteries to store electricity.
This type of battery is common and is also widely used in laptops and smartphones. It uses the movement of lithium ions between the positive and negative electrodes to store and release energy.
As the lithium ions inside the battery move from the negative electrode to the positive electrode through the electrolyte solution, the electrons also flow from the negative electrode to the positive electrode through the battery-connected device, providing it with electricity. When electrons and lithium ions re-gather at the positive electrode, the battery is depleted.
During charging, these ions are sent back to the negative electrode through the electrolyte so that the battery can be discharged again.
Early electric vehicles
The first "electric horse-drawn carriage" was born in Scotland.
After Anyos Jedlik invented the electric motor in 1828, between 1832 and 1839, the Scottish chemist Robert Anderson built the first electric car by fitting a horse-drawn carriage with a battery and an electric motor.
The prototype was rough and the battery was not rechargeable. Perhaps due to the rise of steam power, Anderson's invention was not widely used.
It wasn't until the late 19th century that more "electric carriages" began to appear. In England, Thomas Parker built the first electric car, which was powered by lead-acid batteries.
The next generation of development
The next big advance in the battery space could be solid-state batteries for vehicles. Lithium-ion batteries have many advantages, but they also have some drawbacks, such as battery capacity decaying over time, batteries that overheat easily, and flammable liquid electrolytes used.
Engineers around the world are working to develop the next generation of solid-state batteries, replacing liquid electrolytes with solid-state electrolytes made of materials such as ceramic, glass, or plastic. The latter works on the same principle as liquid electrolytes.
However, it can increase the energy density of the battery, making the battery more efficient. In addition, solid-state electrolytes are non-flammable, so solid-state batteries are safer and less prone to accidents such as spontaneous combustion.
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