Metal lithium strip, pre-lithiated electrode plate, pre-lithiation process, secondary battery, preparation process of the secondary battery, and apparatus
View Patent ↗The present embodiments provide a metal lithium strip, a prelithiated electrode plate, and a prelithiation process. The metal lithium strip comprises a lithium substrate and a metal element doped in the lithium substrate, the metal element comprises at least two of magnesium, boron, aluminum, silicon, indium, zinc, silver, calcium, manganese and sodium; and the metal lithium strip has a strength a, a width w, and a thickness h, satisfying: σ 2 -(w/105h) 2 >0. In the present application, the strength of the lithium strip is adjusted by the doping of the metal elements; meanwhile, the strength of the adjusted lithium strip is matched with its width and thickness ensuring that in the process of rolling the metal lithium strip to a reasonable thickness, the phenomenon of edge cracking of the lithium strip is avoided, lithium metal resources and production costs can be saved, a uniform pre-lithiation effect for electrode plate can also be achieved.
1. A metal lithium strip, comprising a lithium substrate and a metal element doped in the lithium substrate, the metal element comprising at least two of magnesium, boron, aluminum, silicon, indium, zinc, silver, calcium, manganese and sodium; and the metal lithium strip has a strength σ (Mpa), a width w (mm), and a thickness h (mm), which satisfy: σ 2 -(w/105h) 2 >0.
2. The metal lithium strip according to claim 1 , wherein the metal element comprises aluminum element and sodium element.
3. The metal lithium strip according to claim 2 , wherein the aluminum element is present in the metal lithium strip in a mass percentage of 0.12% to 0.3%, and optionally, the aluminum element is present in the metal lithium strip in a mass percentage of 0.15%-0.25%.
4. The metal lithium strip according to claim 2 , wherein the sodium element is present the metal lithium strip in a mass percentage of 0.03% to 0.08%.
5. The metal lithium strip according to claim 3 , wherein the sodium element is present the metal lithium strip in a mass percentage of 0.03% to 0.08%.
6. The metal lithium strip according to claim 1 , wherein the strength σ of the metal lithium strip is 1.23 Mpa to 2.25 Mpa.
7. The metal lithium strip according to claim 2 , wherein the strength σ of the metal lithium strip is 1.23 Mpa to 2.25 Mpa.
8. The metal lithium strip according to claim 3 , wherein the strength σ of the metal lithium strip is 1.23 Mpa to 2.25 Mpa.
9. The metal lithium strip according to claim 4 , wherein the strength σ of the metal lithium strip is 1.23 Mpa to 2.25 Mpa.
10. The metal lithium strip according to claim 1 , wherein the width w of the metal lithium strip is 70 mm to 320 mm; optionally, the width w of the metal lithium strip is 70 mm to 300 mm.
11. The metal lithium strip according to claim 2 , wherein the width w of the metal lithium strip is 70 mm to 320 mm; optionally, the width w of the metal lithium strip is 70 mm to 300 mm.
12. The metal lithium strip according to claim 3 , wherein the width w of the metal lithium strip is 70 mm to 320 mm; optionally, the width w of the metal lithium strip is 70 mm to 300 mm.
13. The metal lithium strip according to claim 4 , wherein the width w of the metal lithium strip is 70 mm to 320 mm; optionally, the width w of the metal lithium strip is 70 mm to 300 mm.
14. The metal lithium strip according to claim 6 , wherein the width w of the metal lithium strip is 70 mm to 320 mm; optionally, the width w of the metal lithium strip is 70 mm to 300 mm.
15. The metal lithium strip according to claim 1 , wherein the thickness h of the metal lithium strip is 1.0 mm to 2.0 mm; optionally, the thickness h of the metal lithium strip is 1.2 mm˜1.8 mm.
16. The metal lithium strip according to claim 6 , wherein the thickness h of the metal lithium strip is 1.0 mm to 2.0 mm; optionally, the thickness h of the metal lithium strip is 1.2 mm˜1.8 mm.
17. The metal lithium strip according to claim 10 , wherein the thickness h of the metal lithium strip is 1.0 mm to 2.0 mm; optionally, the thickness h of the metal lithium strip is 1.2 mm˜1.8 mm.
18. A pre-lithiated electrode plate, wherein the pre-lithiated electrode plate comprises a lithium foil formed from the metal lithium strip according to claim 1 by rolling.
19. A process for pre-lithiation, which comprises:
forming a lithium foil from the metal lithium strip of claiml by rolling; and
compounding the lithium foil with an electrode plate to obtain a pre-lithiated electrode plate.
20. The process for pre-lithiation according to claim 19 , wherein the lithium foil has a thickness of 1 μm˜20 μm; and the rolling has a rolling force of 1T˜7T.