The invention relates to an electrochemical cell for a lithium-ion battery comprising: a negative electrode comprising as an active material silicon; a positive electrode; and an electrolyte positioned between said negative electrode and said positive electrode, said electrolyte comprising at least one lithium salt, at least one carbonate solvent, at least one mononitrile compound and at least one compound fitting at least one of the following formulae (I) and (II): wherein R1 and R2 represent, independently of each other, H, Cl or F, provided that R1 and R2 do not both represent H.