Abstract: The present invention relates to a rechargeable accumulator comprising one or more metal-air cells, each cell comprising a metallic negative electrode, a first positive electrode for releasing oxygen, a second positive electrode which is a porous air electrode containing at least one oxygen reducing catalyst, and an automatic device for protecting the air electrode during the charging and discharging phases of the accumulator. The invention also relates to a method for storing and releasing electrical energy using such an accumulator.

Abstract: The present invention relates to a rechargeable accumulator comprising one or more metal-air cells, each cell comprising a first terminal (1) and a second terminal (2), a metallic negative electrode (3) for metal-air cell, connected to the first terminal (1), a first positive electrode (4) for releasing oxygen, a second positive electrode (5) which is a porous air electrode containing at least one oxygen reducing catalyst, an electrolyte, control means (6) suitable for continuously comparing the voltage measured between the terminal (2) and the terminal (1) with a setpoint value and for dispatching a switching signal to the switching means (7) when the measured voltage becomes smaller than the setpoint value, switching means (7) suitable for receiving a switching signal originating from the control means (6) and for connecting and disconnecting the air electrode (5) of the second terminal (2). The present invention also relates to a method using such an accumulator.