The ornamental design for a waterelectrolysisdevice, as shown and described.
FIG. 1 is a front view of a water electrolysis device according to the invention;
FIG. 2 is a rear view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a top view thereof; and,
FIG. 6 is a bottom view thereof.
All the dotted lines in the figures are directed to environment and are for illustrative purpose only. The dotted lines form no part of the claimed design.