According to the certificate of conformity, the maximum axle load is 760kg for the front axle and 830kg for the rear axle. The maximum total weight is 1570kg.
Before ordering the Lithium battery, I had to bring the car to a scale. So I could verify the curb weight of the converted car (in a somewhat provisional stage), and to see how the axle loads change if you put a weight (=me) on the front seat, backseat or in the trunk.
It's simple mechanics - depending on the distance the weight has from either axle,
Unfortunately, the estimated curb weight of the car has increased a lot, from 1190 to 1332kg, reducing the maximum payload accordingly: The limit on total weight will now only allow for three persons of 75kg each, plus a generous hand luggage of 10kg altogether.
The high weight is of course also due to my decision to choose as large a traction battery as possible, deliberately trading payload and performance against reach.
The weight calculation shows that also for “larger” cars (in terms of what is frequently being used as base car), it absolutely pays to save weight wherever possible. I might have spared quite some kilograms with auxiliary frames and battery boxes made of aluminium.