Method for manufacturing secondary battery and equipment for manufacturing the secondary battery

1 . A method for manufacturing a secondary battery, the method comprising:

an operation (a) of alternately stacking an electrode and a separator to manufacture an electrode assembly;

an operation (b) of laminating the electrode assembly at a pressure of 5 kgf/cm 2 or more to bond the electrode and the separator, which are provided in the electrode assembly, to each other;

an operation (c) of accommodating the electrode assembly in a battery case after operation (b) and injecting an electrolyte into the battery case to seal the battery case, thereby manufacturing a preliminary battery;

an operation (d) of charging and discharging the preliminary battery to activate the preliminary battery, and including a degassing process; and

an operation (e) of aging the preliminary battery at a temperature of 60° C. to 100° C. for 1 hour to 6 hours to thermally treat the preliminary battery,

wherein, in operation (d), the charging and discharging is performed from SOC 25 to SOC 100,

wherein the operation (d) comprises:

a process (d1) of primarily charging the preliminary battery;

a process (d2) of primarily aging the primarily charged preliminary battery at room temperature of 23° C. to 27° C.;

a process (d3) of primarily aging the preliminary battery at a temperature of 50° C. to 80° C. after the process (d2);

a process (d4) of secondarily aging the preliminary battery at the room temperature of 23° C. to 27° C. after the process (d3);

a process (d5) of primarily discharging the preliminary battery after the process (d4); and

an additional degassing process between the process (d4) and the process (d5), and

wherein the operation (d) is repeated two or more times.

2 . The method of claim 1 , wherein, in operation (e), the temperature aging is performed for 1 hour to 3 hours.

3 . The method of claim 1 , wherein, in operation (e), the temperature aging is performed at a temperature of 75° C. to 90° C.

4 . The method of claim 1 , wherein the degassing process is further performed by the temperature aging.

5 . The method of claim 1 , wherein the additional degassing process comprises a process of opening the battery case of the preliminary battery and a process of sealing the battery case again.

6 . The method of claim 1 , wherein the process (d1) is performed from SOC 25 to SOC 35.

7 . The method of claim 1 , wherein the process (d2) is performed for 1 day to 5 days.

8 . The method of claim 1 , wherein the process (d3) is performed for 10 hours to 30 hours.

9 . The method of claim 1 , wherein the process (d4) is performed for 10 hours to 30 days.

10 . The method of claim 1 , wherein the process (d5) is performed to be discharged to 6.5 C for 1 minute at SOC 90.

11 . The method of claim 1 , wherein, in operation (e), the temperature aging is performed at a temperature of greater than 80° C.

12 . The method of claim 1 , wherein, in operation (e), the secondary battery is aged in a state of SOC 25 to SOC 35 after operation (d) has been completed.

13 . The method of claim 1 , wherein the degassing process is performed by each aging of the preliminary battery in operation (d).