Bipolar Li-ion electrochemical battery (A, A1, A2) comprising at least two electrochemical compartments (C1, C2; C1 to C4; C5, C6) arranged adjacent to each other while being electrically connected in series, each of the compartments comprising: - at least one first electrically conductive substrate acting as the current collector comprising two faces (40, 41), wherein a first face supports an electrode according to at least one pattern and the second face supports an electrode according to two patterns (1, 10) at a mutual distance defining an area devoid of patterns, wherein one of the two patterns of the second face is supported in the same area as the pattern of the first face and the first substrate is bent at the area devoid of patterns so as to obtain a U shape with one pattern from the first face opposite one pattern from the second face; - at least one second electrically conductive substrate acting as the current collector comprising two faces (40', 41'), wherein a first face supports an electrode according to at least one pattern and the second face supports an electrode according to two patterns (2, 20) at a mutual distance defining an area devoid of patterns, wherein one of the two patterns of the second face is supported in the same area as the pattern of the first face and the second substrate is bent at the area devoid of patterns so as to obtain a U shape with one pattern from the first face opposite one pattern from the second face, - an electrically insulating separator impregnated with an electrolyte and bent according to an accordion shape nested in each of the U shapes of the first and second substrates which are in turn nested in each other, such that said separator impregnated with electrolyte is in contact with each of the electrode patterns (1, 10, 2, 20); wherein, for each of the compartments (C1, C2, C3, C4; C5, C6), at least one of the first and second substrates forming the end substrates (4e, 4'e) has a face with precisely one electrode pattern (1, 2), wherein, for each of the compartments, the electrode patterns of the same substrate have the same polarity; wherein, for each of the compartments, the electrode patterns of the second substrate have the opposite polarity of those of the electrode of the first substrate; wherein all the first or second substrates of one of the compartments (C1 to C6) are in continuous electrical contact with material continuity with all the second or first substrates of another of the adjacent compartments (C6 to C1) respectively, via the areas thereof devoid of electrode (42, 42') forming the base of the U shapes; wherein the electrode (1, 10) of the substrates of one compartment, in continuous electrical contact, have the opposite polarity of those (2, 20) of the substrates of the other adjacent compartment, in continuous electric contact, thus defining a bipolar current collector; the battery further comprising an electrically insulating seal arranged on each peripheral edge of each compartment not coated with a substrate or with the continuous electrical contact area (5, 50, 42, 42') with material continuity between substrates, so as to seal the electrolytes and isolate the compartments from the ambient air. - at least one first electrically conductive substrate acting as the current collector comprising two faces (40, 41), wherein a first face supports an electrode according to at least one pattern and the second face supports an electrode according to two patterns (1, 10) at a mutual distance defining an area devoid of patterns, wherein one of the two patterns of the second face is supported in the same area as the pattern of the first face and the first substrate is bent at the area devoid of patterns so as to obtain a U shape with one pattern from the first face opposite one pattern from the second face; - at least one second electrically conductive substrate acting as the current collector comprising two faces (40', 41'), wherein a first face supports an electrode according to at least one pattern and the second face supports an electrode according to two patterns (2, 20) at a mutual distance defining an area devoid of patterns, wherein one of the two patterns of the second face is supported in the same area as the pattern of the first face and the second substrate is bent at the area devoid of patterns so as to obtain a U shape with one pattern from the first face opposite one pattern from the second face, - an electrically insulating separator impregnated with an electrolyte and bent according to an accordion shape nested in each of the U shapes of the first and second substrates which are in turn nested in each other, such that said separator impregnated with electrolyte is in contact with each of the electrode patterns (1, 10, 2, 20);