LAMINATED PIEZOELECTRIC ELEMENT, INJECTION DEVICE USING SAME, AND FUEL INJECTION SYSTEM

[Problem] Provided is a highly-durable multi-layer piezoelectric element that is free from peeling of external electrode off a stacked body even when driven to operate for long hours under a high electric field and high pressure. [Solution] A multi-layer piezoelectric element (1) includes a stacked body (7) configured so that piezoelectric layers (3) and internal electrode layers (5) are alternately laminated, and an external electrode (8) composed of a sintered material of both electrically conductive particles and a glass, the external electrode (8) which is bonded to a side surface of the stacked body (7) and makes electrical connection with the internal electrode layers (5). The external electrode (8) has a stacked body-side layer region (8a) containing glass as secondary constituent at its stacked body-facing side, and an exterior-side layer region (8b) containing glass as minor constituent at its exterior side. The glass of the exterior-side layer region (8b) is distributed along grain boundary of the conductive particles on an outermost surface of the exterior-side layer region (8b).