Energy transmission device, notably a battery or energy generating device, characterized in that it comprises: - at least one module arranged within a casing, comprising a plurality of independent electrical power links (27, 29) and a plurality of blocks, each comprising: - at least one first electrical power link connected to a pair of connectors (A1, B1), and - a plurality of cells electrically connected to this first electrical power link, allowing these cells to be connected to components that are external to the module by means of the pair of connectors (A1, B1), and - the pair of connectors (A1, B1), which is arranged on the casing of the module, so as to be capable of electrical connection to an electrical connector of a second module that would comprise a same pair of connectors, - switches that are capable of modifying the electrical link between a plurality of cells of the block, notably allowing connection of two cells in series or shunting of one or more cell(s), in order to be able to vary the voltage between the pair of connectors (A1, B1), - a connection component allowing electrical connection of a plurality of independent electrical power links (27, 29) of the at least one module, - a plurality of output connectors (A1, A2; A1; CP) allowing polyphase, notably three-phase, electrical linking of the energy transmission device to an outer component, each output connector being electrically connected to at least one electrical power link (27, 29) of a block of one or more modules of the energy transmission device. - at least one module arranged within a casing, comprising a plurality of independent electrical power links (27, 29) and a plurality of blocks, each comprising: - at least one first electrical power link connected to a pair of connectors (A1, B1), and - a plurality of cells electrically connected to this first electrical power link, allowing these cells to be connected to components that are external to the module by means of the pair of connectors (A1, B1), and - the pair of connectors (A1, B1), which is arranged on the casing of the module, so as to be capable of electrical connection to an electrical connector of a second module that would comprise a same pair of connectors, - switches that are capable of modifying the electrical link between a plurality of cells of the block, notably allowing connection of two cells in series or shunting of one or more cell(s), in order to be able to vary the voltage between the pair of connectors (A1, B1), - at least one first electrical power link connected to a pair of connectors (A1, B1), and - a plurality of cells electrically connected to this first electrical power link, allowing these cells to be connected to components that are external to the module by means of the pair of connectors (A1, B1), and - the pair of connectors (A1, B1), which is arranged on the casing of the module, so as to be capable of electrical connection to an electrical connector of a second module that would comprise a same pair of connectors, - switches that are capable of modifying the electrical link between a plurality of cells of the block, notably allowing connection of two cells in series or shunting of one or more cell(s), in order to be able to vary the voltage between the pair of connectors (A1, B1), - a connection component allowing electrical connection of a plurality of independent electrical power links (27, 29) of the at least one module, - a plurality of output connectors (A1, A2; A1; CP) allowing polyphase, notably three-phase, electrical linking of the energy transmission device to an outer component, each output connector being electrically connected to at least one electrical power link (27, 29) of a block of one or more modules of the energy transmission device.