Same thing happened to me,if you use a thin allen key/s you should be able to remove broken piece,then get new key cut easily,the chip is in the plastic section at the top of the key,NOT in the large plastic piece attached to it,I found this out to late and spent 1hr in a small skip looking for it,thanks for nothing AA,you will need this,due to not having key code and cost,I taped this to the new key,well in the end a taped it to the sensor after pulling from barrel but of cause it is always immobilised,it had to be in the centre so used some polystyrene to push it in and taped up worked a treat
I then had all my locks changed a few months latter,as the local louts had broken them one by one,at great expense and they would not fit ignition as I did not have the code they said I needed to replace it,I switched it over and indeed ,it did not start,however disconnected battery and connected 5 mins latter and all worked ok
I drove away next day had a diesel leak on high pressure side when engine started,repaired that,then went to drive off and exhaust dropped off,so thought to myself,someone trying to tell me something here and went and got a new van,loved the peugeot expert though
As said key chip in plastic key top not attached piece as many believe