The all electric championship's opener on the streets of Beijing ended in controversial circumstances with race long leader Prost making contact with Heidfeld, who had reeled in the e.dams driver during the closing laps.
The contact pitched Heidfeld into a nasty aerial crash with the catch fencing. Luckily the former F1 star managed to clamber from the wreckage unaided.
As a result of the incident, di Grassi took the chequered flag to make history with Andretti Autosport's Franck Montagny and Daniel Abt completing the podium.
There was yet more drama post race as officials handed Abt a penalty for using too much electric energy demoting the German to 10th. Virgin Racing's Sam Bird inherited the final place on the podium.
Prost made no mistakes at the start as he converted his pole position into the lead as the field streamed into the first turn. Di Grassi slotted into second with Daniel Abt in third.
Hopes of completing the first lap of the championship without drama were short-lived when Bruno Senna came to a halt at the second corner, which forced the deployment of the Safety Car.
Racing continued on lap five once Senna's Mahindra machine was removed with Prost leading the pack.
The lead trio headed by e.dams driver Prost, di Grassi and Abt began to move away from the rest of the field.
Meanwhile, pre-season pacesetter Sebastien Buemi encountered yet more issues after being forced into the pits with a rear wing failure. The former Toro Rosso driver was able to rejoin the race.
Prost retained his lead after the field completed their mandatory put-stop featuring the championship's unique car swap procedure.
The son of four-time F1 world champion Alain Prost, appeared to have the race under control until the final laps.
However, a hard charging Heidfeld began to take chunks out of the Frenchman's lead with just half a second separating the pair on the penultimate lap.
Heidfeld continued to apply pressure which came to a head on the final lap when the pair made contact, sending the ex-Sauber F1 man into a dramatic aerial crash. Both drivers emerged from the wreckage unscathed.
Di Grassi took full advantage of the clash to take the win for the Abt squad.
Andretti Autosport's Charles Pic came home in fourth just ahead of Karun Chandhok and Jerome d'Ambrosio.
Oriol Servia finished in seventh spot in front of Nelson Piquet Jnr and sportscar ace Stephane Sarrazin. Following his penalty Abt secure the final points paying position in 10th.
The controversial clash between Nick Heidfeld and Nicolas Prost