Sodium secondary battery module

A sodium secondary battery module, comprising:

• unit stacks in which a plurality of unit cells are laminated, each of the unit cells respectively having a solid electrolyte, a positive electrode component and a negative electrode component which have plate-shape and sealed with an upper cap and a lower cap, the positive electrode component and the negative electrode component respectively disposed on two sides of the solid electrolyte;
• a stacking guide interposed in a space between the unit stacks to support the unit stacks in a state in which the plurality of unit stacks are spaced apart and arranged in columns and rows;
• and
• a case for accommodating the unit stack and the stacking guide,
• wherein the case comprises a lower case having an internal space and accommodating the plurality of unit stacks and the separator therein, an upper case covering the lower case and applying surface pressure to each of the plurality of unit stacks, and a surface pressure adjusting portion fastened in a structure penetrating through the lower case and the upper case to maintain and adjust the surface pressure of the unit stack,
• the surface pressure adjusting portion comprises a fastening bolt inserted into a fastening hole formed in the upper case in an upper portion of the upper case and a fastening hole formed in a protruding portion of the lower case, a fastening nut screw coupled to the fastening bolt in a lower portion of the lower case, and an elastic body interposed between the fastening bolt and the upper case,
• the upper case includes a balancing plate on a surface, facing the unit stack in order to equalize the surface pressure, applied to each of the plurality of unit stacks, and
• the balancing plate is made of a material having elastic properties.