I think it is more specifically electric planes as large as commercial airline passenger planes are impossible. It has a lot to do with battery mass to energy content ratio. Kerosine is about 46.4 MJ (megajoules) per kilogram. Lithium-air batteries, for example, only have about 6.12 MJ/kg.
So, that means you need 7 times as much battery (in mass) to have the same energy content of kerosine fuel. Naively, we can maybe say that means electric planes only have 1/6 of the range of an equivalent kerosine plane.[^]
Interestingly, lithium-air batteries theoretically have the largest possible energy density for any battery at 40.1 MJ/kg.
^ The calculations are really basic and probably only slightly reflect reality (since there are many other important factors. For example, Hydrogen has a lot more energy per kilogram than kerosine, but because it is much less dense, it has much less energy per m^3 than kerosine. This has made hydrogen gas very impractical for either internal-combustion engines, or planes), but I think it gives an idea of what the problem is.
That's called a subpeona, Mr. Trump.