How battery capacity affects range? A car's range depends on its battery's capacity and efficiency of use. Generally, most vehicles will need 20 to 30kW of power on highways for a steady speed.
As technology advances, the capacity of electric car batteries is likely to improve. You'll find a wide range EV battery capacities across different car models. Smaller city cars might have batteries as small as 30kWh for shorter commutes, while high-end, luxury or very large EVs can have battery capacities exceeding 100kWh.
What is the battery capacity of an EV?
However, there are some exceptions with short-range EVs that have lower capacities ranging between 30 kWh and 40 kWh. Large electric SUVs like the Tesla Model X and Mercedes-Benz EQS SUV have larger battery packs that range from 100 kWh to 120 kWh. But some battery packs are even larger.
All electric car batteries have a usable capacity that's slightly less than the gross capacity because this helps extend the life of the battery pack. That buffer prevents it from ever being completely charged. For example, the Audi Q8 e-tron's battery pack has a gross capacity of 114 kWh, but its usable capacity is 106 kWh.
In the EV world, kilowatt-hours are to batteries as gallons are to gas tanks. But a full battery can't be completely equated with a full fuel tank. All electric car batteries have a usable capacity that's slightly less than the gross capacity because this helps extend the life of the battery pack.
How many kWh should a car battery be?
For other drivers, batteries over 30 or 40 kWh are needed to cover the required range. In the most extreme case, corresponding to highway driving for almost 2 h in a cold climate, the minimum sized battery was 70 kWh.
A high battery capacity, however, provides an important marketing tool and for this reason, it is unlikely that manufacturers will reduce the ranges of EVs in the short term, unless forced to by legislation or lack of available material.