Usable vs gross battery capacity
Gross capacity is everything the battery physically holds; usable capacity is the part the car lets you drive on. Range comes from usable.
Electric car spec sheets often quote two battery sizes, and the gap between them confuses shoppers. Gross capacity is the total energy the cells physically store. Usable battery capacity is the portion the car actually makes available for driving; the remainder is held back by the car's software, and how much varies by model.
Usable is the number that matters. Range, efficiency math and charging cost all flow from it: usable kWh divided by consumption in kWh/100 km gives a range estimate, and the US Environmental Protection Agency gives the same arithmetic in miles, where 100 kWh of usable capacity at two miles per kWh is 200 miles per charge. The Australian Government compares battery capacity in kWh to a fuel tank's capacity, and says a larger capacity can mean a longer range, but that range also depends on vehicle size, efficiency, driving style, terrain and climate.
A larger gross figure does not guarantee a larger usable one. CarPairly lists usable capacity as the battery figure for every electric car, and comparisons on the site always use usable against usable.