Apparatus for pre-lithiation of negative electrode and method for pre-lithiation of negative electrode

An apparatus for pre-lithiating a negative electrode, the apparatus comprising:

• a pre-lithiation reactor sequentially divided into an impregnation section, a pre-lithiation section and an aging section, the pre-lithiation reactor accommodating a pre-lithiation solution through which a negative electrode structure is movable;
• a negative electrode roll arranged outside the pre-lithiation solution, the negative electrode structure being wound on the negative electrode roll before being moved through the pre-lithiation solution;
• a lithium metal counter electrode arranged in the pre-lithiation solution in the pre-lithiation section, the lithium metal counter electrode being spaced apart from the negative electrode structure by a predetermined distance to face the negative electrode structure while the negative electrode structure is moved through the pre-lithiation solution;
• and
• a charge and discharge unit connected to the negative electrode structure and the lithium metal counter electrode,
• wherein a separation distance between the lithium metal counter electrode and the negative electrode structure is in a range of 7 to 15 mm,
• wherein the negative electrode structure includes:
• a negative electrode current collector,
• a negative electrode active material layer on at least one surface of the negative electrode current collector, and
• a non-coated part on the at least one surface of the negative electrode current collector in a width direction of, and adjacent to, the negative electrode active material layer, and
• wherein the lithium metal counter electrode is arranged to overlap only the negative electrode active material layer in a direction perpendicular to a travel direction of the negative electrode as the negative electrode moves in the pre-lithiation section.