That would appear to be a series motor controller, so yes, it is the type you need.
SepEx means the motor's field is excited (power and controlled) separately from the armature. A series motor, like which you linked to, has the field connected in series with the armature, so the field excitation is provided with the armature current is always the same strength as the armature.
Those motors are unsuitable for any reasonable size EV. Maybe some real small thing, but will struggle to carry its own weight and even a single person. Possibly a go-kart, but I wouldn't expect them too last long
Seems like you should have researched this a while ago. But WTH, good luck.