Electrode assembly manufacture and device

A method for the preparation of an electrode assembly, the method comprising:

• providing a stacked population of unit cells comprising a population of negative electrode subunits, a population of separator layer subunits, and a population of positive electrode subunits, each unit cell in the stacked population comprising at least a unit cell portion of a member of the negative electrode subunit population, a member of the separator layer subunit population, and a unit cell portion of a member of the positive electrode subunit population, wherein (i) the negative electrode subunit and positive electrode subunit face opposing surfaces of the separator layer comprised by such stacked unit cell population member and (ii);
• the separator layer comprised by such stacked unit cell population member is adapted to electrically isolate the portion of the negative electrode subunit and the portion of the positive electrode subunit comprised by such stacked unit cell while permitting an exchange of carrier ions between the negative electrode subunit and the positive electrode subunit comprised by such stacked unit cell;
• wherein the members of the population of negative electrode subunits have a first set of two opposing end surfaces, and opposing end margins adjacent each of the first set of opposing end surfaces, and members of the population of positive electrode subunits have a second set of two opposing end surfaces, and opposing end margins adjacent each of the first set of opposing end surfaces, and
• wherein members of the population of negative electrode subunits comprise at least one subunit weakened region in at least one of the opposing end margins of the negative electrode subunit members, or members of the population of positive electrode subunits comprise at least one subunit weakened region in at least one of the opposing end margins of the positive electrode subunit members;
• and
• applying tension to:
• (i) at least one of the opposing end margins of the negative electrode subunit members in a tensioning direction, to remove a portion of the negative electrode subunit members that is adjacent the weakened region in the at least one opposing end margin, such that at least one of the first set of opposing end surfaces of the negative electrode subunit comprises at least one end surface exposed by removal of the portion, or
• (ii) at least one of the opposing end margins of the positive electrode subunit members in a tensioning direction, to remove a portion of the positive electrode subunit members that is adjacent the weakened region in the at least one opposing end margin, such that at least one of the second set of opposing end surfaces of the positive electrode subunit comprises at least one end surface exposed by removal of the portion.