Cable-type secondary battery
The present disclosure provides a cable-type secondary battery, comprising: an inner electrode; a separation layer surrounding the outer surface of the inner electrode to prevent a short circuit between electrodes; and a sheet-form outer electrode spirally wound to surround the separation layer or the inner electrode.
1. A method of manufacturing a cable-type secondary battery, comprising:
providing an inner electrode;
winding a separation layer on an outer surface of the inner electrode; and
helically winding a sheet-form outer electrode on an outer surface of the separation layer,
wherein, before the step of helically winding, the method further comprises forming the outer electrode by applying a slurry containing an outer electrode active material on a surface of a sheet-form outer current collector to form an outer electrode active material layer.
2. The method according to claim 1 , wherein the step of forming the outer electrode further comprises forming a second supporting layer on another surface of the sheet-form outer current collector.
3. The method according to claim 2 , wherein the step of forming the outer electrode further comprises applying a slurry containing a conductive material and a binder on the outer electrode active material layer.
4. The method according to claim 3 , wherein the step of forming the outer electrode further comprises placing a first porous supporting layer on the slurry containing the conductive material and the binder, and compressing the resultant to form a conductive layer adhered between the outer electrode active material layer and the first porous supporting layer.
5. The method according to claim 1 , wherein the step of helically winding includes helically winding the sheet-form outer electrode so that it does not overlap itself.
6. The method according to claim 1 , wherein the step of providing the inner electrode includes forming an inner electrode active material layer on a surface of a wire-form inner current collector.
7. The method according to claim 6 , wherein the step of forming the inner electrode active material layer is carried out by an electroplating process or an anodic oxidation process.
8. The method according to claim 6 , wherein the step of forming the inner electrode active material layer includes applying an electrode slurry containing an active material through a comma coater, through a slot die coater, by way of dip coating, or by way of extrusion-coating using an extruder.
9. The method according to claim 1 , wherein the step of providing the inner electrode includes forming a hollow inner electrode having an empty central part.
10. The method according to claim 9 , further comprising forming a core for supplying lithium ions by introducing an electrolyte into the empty central part of the hollow inner electrode.
11. The method according to claim 10 , wherein the step of forming the core includes introducing a non-aqueous electrolyte solution into the empty central part of the hollow inner electrode.
12. The method according to claim 10 , further comprising sealing an introduction part of the electrolyte.
13. The method according to claim 1 , further comprising forming a core for supplying lithium ions by forming a polymer electrolyte into a wire form using an extruder.
14. The method according to claim 13 , wherein the step of forming a core occurs before the step of providing an inner electrode.
15. The method according to claim 1 , further comprising forming a core for supplying lithium ions by providing a wire-form carrier made of a sponge material and introducing a non-aqueous electrolyte solution therein.
16. The method according to claim 1 , further comprising forming a protection coating to surround an outer surface of the sheet-form outer electrode.
17. The method according to claim 16 , wherein, after forming the protection coating, the method further comprises forming a core for supplying lithium ions by introducing an electrolyte into an empty central part of the inner electrode.
18. The method according to claim 1 , wherein the separation layer is a sheet-form separation layer.
19. A method of manufacturing a cable-type secondary battery, comprising:
providing an inner electrode;
winding a separation layer on an outer surface of the inner electrode; and
helically winding a pre-formed sheet-form outer electrode on an outer surface of the separation layer, the outer electrode including an outer electrode active material layer on a surface of a sheet-form outer current collector.
20. The method according to claim 19 , wherein the step of helically winding includes helically winding the sheet-form outer electrode so that it does not overlap itself.