The motor has 134kW. The battery has 4.7kWh supposedly. So at FULL motor energy output, an motor efficiency of around 0.9, you would be using roughly 150kW, so your 4.7kWh would last... 110 seconds.
How much regen will do, is a big question I guess, that is hard to say.
You do not need the boost for much more than 15 seconds or so at a time I would say?
I am rather amazed that they claim they can do 10km on battery alone though. That would mean in the EPA cycle their usage is 470 Wh per km. I guess thats not too bad though. They should have bought the motor from Tesla, it has half the usage and 400hp.