Humidifier for fuel cell and method for manufacturing same

A humidifier for a fuel cell, the humidifier comprising:

• a humidifying module configured to humidify gas supplied from outside using moisture in off-gas discharged from a fuel cell stack;
• and
• an upper cap and a lower cap, coupled respectively to an upper end and a lower end of the humidifying module, the upper cap including a protrusion,
• wherein the humidifying module comprises:
• a mid-case open at opposite ends thereof, the mid-case having an interior step at an inner circumferential surface thereof, the mid-case having a first port for off-gas introduction and a second port for off-gas discharge;
• a plurality of hollow fiber membranes disposed in the mid-case;
• a fixing layer in which ends of the hollow fiber membranes are potted, the fixing layer having an exterior step at an outer circumferential surface thereof;
• a bracket being in contact with the fixing layer, a portion of a bottom of the bracket being supported by the interior step at the inner circumferential surface of the mid-case and a remaining portion of the bottom of the bracket being supported by the exterior step at the outer circumferential surface of the fixing layer;
• and
• a packing member having a lower groove into which an end of the mid-case is inserted and an upper groove into which the protrusion of the upper cap is inserted,
• wherein the packing member being in contact with the bracket, and
• wherein the bracket has higher hardness than the packing member,
• wherein the humidifying module further comprises a first inner case which is separately provided from and inserted into the mid-case,
• wherein at least a portion of the hollow fiber membranes are disposed in the first inner case,
• wherein the mid-case has a partition wall configured to divide an inner space thereof into an off-gas introduction space corresponding to the first port and an off-gas discharge space corresponding to the second port,
• wherein the first inner case is inserted into the mid-case through a first hole formed in the partition wall so as to be supported by the partition wall,
• wherein the first inner case has a first group of holes located in the off-gas introduction space and a second group of holes located in the off-gas discharge space such that off-gas introduced into the first inner case from the off-gas introduction space through the first group of holes flows inside the first inner case and comes out to the off-gas discharge space through the second group of holes,
• wherein an end of the first inner case is potted in the fixing layer, and
• wherein the ends of the hollow fiber membranes protrude from the end of the first inner case such that the ends of the hollow fiber membranes potted in the fixing layer are open while the end of the first inner case potted in the fixing layer is entirely within the fixing layer.