I agree that they are at least misrepresenting their achievement. However, for the sake of argument, electric motor efficiency goes down quite a lot as overall power potential and RPM both drop. So it's possible they've come up with a sizeable efficiency improvement in a worst-case scenario, i.e., improving efficiency of a small motor in low RPM, part throttle situations.

If that's the case, however, it doesn't really bode well for them, as their efficiency gains will not translate to the high-RPM, high-power motors used in cars. I'm not EE, but I do know that most engineering involves making trade-offs. So I wouldn't be surprised to learn that techniques to improve low-power, low-RPM efficiency probably sacrifices high-power, high-RPM efficiency.