1. A method for managing bad memory blocks in a nonvolatile-memory device, said nonvolatile-memory device comprising a plurality of available memory blocks each of which is associated with a respective logic address, said management method comprising steps of: dividing the available memory blocks into a first set and a second set, the first set being formed by addressable memory blocks that are to be used by a user, and the second set being formed by spare memory blocks reserved for replacement of bad addressable memory blocks, each memory block assuming, in a respective set, a respective position; and re-mapping the bad addressable memory blocks in corresponding spare memory blocks, said step of re-mapping comprising a step of: constructing a data base containing, for each bad addressable memory block, information indicating a logic address of a corresponding spare memory block, said step of constructing the data base comprises steps of: seeking bad spare memory blocks; storing a logic address of each bad spare memory block in a re-directing vector in a position corresponding to that of the bad spare memory block in the second set; seeking bad addressable memory blocks; and storing a logic address of each bad addressable memory block in a free position in the re-directing vector.