Negative electrode comprising mesh-type current collector, lithium secondary battery comprising the same, and manufacturing method thereof
The present disclosure relates to a negative electrode for a lithium secondary battery comprising a mesh-type current collector and a lithium thin film, and in particular, to a negative electrode in which a lithium thin film is inserted to an opening of a current collector and empty space is formed, a lithium secondary battery comprising the same, and a manufacturing method thereof. The present disclosure is capable of enhancing safety of the lithium secondary battery by preventing lithium dendrite growth. In addition, the present disclosure is capable of preventing stripping of the negative electrode current collector and the lithium thin film while charging and discharging the battery since adhesion efficiency increases between the negative electrode and the current collector.
1. A negative electrode for a lithium secondary battery comprising:
a mesh-type anode current collector formed with a wire rod portion and an opening; and
a lithium thin film formed with an inserted portion inserted to the opening of the negative electrode current collector and a non-inserted portion that is not inserted,
wherein a thickness of the inserted portion of the lithium thin film is 20% to 60% of a thickness of the whole lithium thin film,
wherein a thickness of the non-inserted portion of the lithium thin film is 40% to 80% of a thickness of the whole lithium thin film, and
wherein the thickness of the lithium thin film is thicker than the thickness of the negative current collector.
2. The negative electrode for a lithium secondary battery of claim 1 , wherein a thickness of the lithium thin film is from 10 μm to 800 μm.
3. The negative electrode for a lithium secondary battery of claim 1 , wherein the wire rod portion of the negative electrode current collector has a line width of 50 μm to 500 μm and line spacing of 100 μm to 1 mm.
4. The negative electrode for a lithium secondary battery of claim 1 , wherein a shape of the opening of the negative electrode current collector is circular, oval or polygonal.
5. The negative electrode for a lithium secondary battery of claim 1 , wherein an aperture ratio of the negative electrode current collector is from 20% to 80%.
6. The negative electrode for a lithium secondary battery of claim 1 , wherein a thickness of the negative electrode current collector is from 3 μm to 500 μm.
7. The negative electrode for a lithium secondary battery of claim 1 , wherein the negative electrode current collector is one or more types selected from the group consisting of copper, aluminum, stainless steel, zinc, titanium, silver, palladium, nickel, iron, chromium, alloys thereof and combinations thereof.