Abstract: This invention relates to a process for charging a reversible electrochemical generator consisting of a plurality of cells, which are electrically in series, comprising a zinc negative electrode and a positive electrode between which a basic electrolyte, containing solubilized zinc, circulates, consisting in making the electrolyte in the cells circulate successively from one cell to the next and in applying to it a charging current forming a succession of approximately rectangular pulses. The direction of circulation of the electrolyte during charging is periodically reversed.

Abstract: A hydraulic generator with a free-piston engine and hydropneumatic return cushion and with an associated hydraulic-fluid pumping piston feeding a hydraulic accumulator intended to be charged between two detected levels of pressure. The generator includes a lock device for the free piston at the power-stroke dead center with voluntary control, and servo-control means for this lock device with means for detection of the aforementioned two pressure levels, to assure locking the piston in response to detection of the aforementioned highest pressure level and to assure its unlocking in response to detection of the aforementioned lowest pressure level, and thus an automatic intermittent running of said engine.