Multi-layer piezoelectric element, and ejection apparatus and fuel ejection system that employ the same

The application refers to a multi-layer piezoelectric element (1) comprising a multi-layer structure (7) in which a plurality of ceramic layers (21) and a plurality of internal electrodes (11) are stacked alternately one on another, wherein the plurality of ceramic layers (21) comprise piezoelectric material layers (3) and low-rigidity ceramic layer (23) that has rigidity lower than those of the piezoelectric material layer (3) and the internal electrode (11), wherein the low-rigidity ceramic layer (23) comprises a plurality of ceramic parts (25) that are separated from each other, and wherein at least one of the ceramic parts (25) is bonded with only one piezoelectric material layer (3) among the two piezoelectric material layers (3) that adjoin in the stacking direction.