Pressure storage unit for a camshaft and piston for a pressure storage unit

A pressure storage unit for a camshaft, comprising an integrated controllable pressure storage device for supporting hydraulic engine components having a housing with a piston mounted movably therein between an initial, uncharged position and a charged position, the piston including a piston floor, and a spacer element on the piston floor, in the initial, uncharged position the spacer element prevents the piston floor from contacting an oppositely situated housing floor, and in the charged position hydraulic fluid is supplied to a space between the housing floor and the piston floor, wherein the piston has a multi-part construction and includes a sleeve body as a piston skirt in which the piston floor is accommodated.