Electronic lock cylinder

Electronic lock cylinder (10) having a cylinder housing (24) which is insertable into an opening in a mortise (12) with a shaft (26) which is mounted about a longitudinal axis (27) rotatable in the cylinder housing (24) and is rotationally fixedly connected to one axial end with an actuating element (28) with a to the cylinder housing (24) about the longitudinal axis rotatably mounted locking cam (30), arranged in the actuating element (28) an electrical and / or electronic assembly (49) is characterized in that the shaft (26) with the actuating element (28) via a thermal protection element (60) is connected.