Although the engine is the source of the driving force of the electric vehicle, the battery pack is practically “heart and soul”. If you are looking for a new or used electric car, what you will definitely want to pay attention to are the battery specifications. Of course, you need to be aware of other aspects that will ultimately affect their performance.
Electric vehicles use lithium-ion batteries of various designs, similar to those found in smartphones and laptops, only larger in size. Lithium-ion batteries have a high energy density and are less prone to loss of charge when not in use.
Car battery capacity is expressed in kilowatt hours (kWh). In this case, more is better. Choosing a vehicle with a larger capacity is like buying a car that comes with a larger fuel tank. So, with one charge, you will be able to cover a larger number of kilometers before refilling. However, you must be aware that due to the way the EV works, you will never have access to the full capacity of the battery. The reason is that the car’s management system prevents the battery from being 100% full or completely discharged, as this preserves efficiency and prolongs its life.
The battery capacities of current electric cars vary from 17.6 kWh in the Smart EQ ForTwo with an autonomy of only 95 kilometers, to 100 kWh in the Tesla Model S and Model X, which can cover over 500 kilometers before they have to “jump” to the bottling plant. Battery capacity and other relevant specifications for all current electrical models can be found online.
Electric car battery capacity
Perhaps the most critical factor to consider when buying an electric car is the estimated autonomy that the battery provides when fully charged, and by stricter procedures, such as WLTP or EPA. You can find data related to the energy consumption of the desired model, as well as the consumption of all current and past electrical models.
As in the case of conventional cars, electric autonomy, and energy consumption in controlled laboratory conditions are tested with electric ones. They are mounted on a dynamometer, which simulates driving conditions in urban areas and outdoors, through a standardized protocol. The electric car starts the test with fully charged batteries and is operated until they are completely discharged.
What is also important is that the potential of the battery will be significantly reduced during cold weather, but also in extreme heat. Low temperatures can significantly reduce battery performance as well as compromise their ability to charge. In addition, while gasoline engines generate a large amount of heat that can be used to heat the cabin space, in electric cars all the necessary energy comes from the battery.
A recent study found that when the mercury on the thermometer scale drops to -7 degrees Celsius, and the cabin heating function is engaged, the average autonomy drops by as much as 41 percent. This means that a model that can nominally cover 250 kilometers in a combined cycle will not be able to cover more than about 145 kilometers in this case. The same study found that when the outside temperature is 35 degrees Celsius and the air conditioner is in use, the autonomy is reduced by an average of 17 percent.
Most of the charging of electric vehicles takes place at home. Depending on the battery capacity of the vehicle, it takes eight to more than 16 hours to charge the battery this way.
A faster alternative is a system of public charging stations, known as DC Fast Charging. They can charge 80 percent of the battery in just 30 minutes, which of course depends on the vehicle itself.