Patent ID: 11967734
Assignee: LG ENERGY SOLUTION, LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 12:
13. A secondary battery comprising:
an electrode assembly; and
a battery case configured to accommodate the electrode assembly,
wherein the electrode assembly comprises:
a radical unit in which electrodes and separators are alternately stacked, the radical unit having one electrode stacked at the uppermost end; and
a separation sheet disposed at the uppermost end of the radical unit,
wherein the separation sheet comprises:
a separation part disposed at the uppermost end of the radical unit;
a pair of side surface protection parts, each of the pair of side surface protection parts connected to a side surface of the separation part and folded to contact a side portion of the radical unit to cover the side surfaces of the radical unit;
a pair of bottom surface protection parts, each of the pair of bottom surface protection parts connected to a lower end surface of one of the side surface protection parts and folded to contact a lowermost end surface of the radical unit; and
a punching hole through which foreign substances do not pass, but an electrolyte passes, in at least one of the pair of side surface protection parts of the separation sheet,
wherein the separation part has a width extending between the pair of side surface protection parts,
wherein a combined width of the pair of bottom surface protection parts is less than half the width of the separation part,
wherein the pair of side surface protection parts adhere to side surfaces of each of the separators provided in the radical unit, and
wherein adhesion between the pair of side surface protection parts and the side surfaces of the separators is less than adhesion between each of the electrodes and the separators in the radical unit.