Microbattery and method for manufacturing a microbattery

A method for manufacturing a microbattery comprising the following steps of:

• forming a stack of thin films on a first substrate comprising, successively, starting from the first substrate, a first current collector, a first electrode, an electrolyte, and a first metal film,
• forming a second current collector on a face of a second substrate, and
• forming a second electrode, said step of forming the second electrode comprising an assembly step of said first and second substrates by soldering the first metal film and the second current collector together using a solder ball previously deposited on a contact face of the first metal film or on a contact face of the second current collector, said first and second substrates being placed facing each other during the assembly step, so as to obtain the second electrode formed by a solder joint comprising at least one intermetallic compound resulting from an interdiffusion of a metallic species of the solder ball and of the first metal film.