Hybrid type secondary battery including electrodes having different output and capacity properties
View Patent ↗Disclosed herein is a battery cell having an electrode assembly, including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, mounted in a receiving part of a battery case, wherein a positive electrode terminal and a negative electrode terminal protrude from at least one side of the electrode assembly, and an insulative material is provided between the electrode assembly and the battery case.
1. A secondary battery having an electrode assembly, comprising at least one positive electrode, at least one negative electrode, and at least one separator interposed between the positive electrode and the negative electrode, mounted in a battery case, wherein
positive electrodes and negative electrodes having different output and capacity properties are provided in combination of a positive electrode and a negative electrode,
positive electrode materials added to opposite major surfaces of a positive electrode current collector exhibit different output and capacity properties,
negative electrode materials added to opposite major surfaces of a negative electrode current collector exhibit different output and capacity properties, and
in the positive electrode and the negative electrode, which face each other in a state in which the separator is interposed between the positive electrode and the negative electrode, the positive electrode material added to one major surface of the positive electrode current collector facing the separator and the negative electrode material added to one major surface of the negative electrode current collector facing the separator exhibit higher capacities or lower capacities than the electrode materials added to the other major surfaces of the electrode current collectors in combination of the positive electrode and the negative electrode.
2. The secondary battery according to claim 1 , wherein the electrode assembly is configured to have a wound type structure, a stacked type structure, a stacked and folded type structure, or a laminated and stacked type structure.
3. The secondary battery according to claim 1 , wherein
the positive electrode comprises a relatively high-output, low-capacity positive electrode material added to one main surface of the positive electrode current collector and a relatively low-output, high-capacity positive electrode material added to the other main surface of the positive electrode current collector, and
the negative electrode comprises a relatively high-output, low-capacity negative electrode material added to one main surface of the negative electrode current collector and a relatively low-output, high-capacity negative electrode material added to the other main surface of the negative electrode current collector.
4. The secondary battery according to claim 3 , wherein the electrode assembly is configured such that one major surface (a) of the positive electrode, to which the relatively high-output, low-capacity positive electrode material is added, and one major surface (b) of the negative electrode, to which the relatively high-output, low-capacity negative electrode material is added, face each other in a state in which the separator is interposed between the one major surface (a) of the positive electrode and the one major surface (b) of the negative electrode.
5. The secondary battery according to claim 3 , wherein the electrode assembly is configured such that the other major surface (c) of the positive electrode, to which the relatively low-output, high-capacity positive electrode material is added, and the other major surface (d) of the negative electrode, to which the relatively low-output, high-capacity negative electrode material is added, face each other in a state in which the separator is interposed between the other major surface (c) of the positive electrode and the other major surface (d) of the negative electrode.
6. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity positive electrode material is at least one selected from a group consisting of lithium manganese oxide (LMO), lithium iron phosphate (LFP), lithium nickel manganese cobalt oxide (NMC), and lithium nickel cobalt aluminum oxide (NCA).
7. The secondary battery according to claim 3 , wherein the relatively low-output, high-capacity positive electrode material is at least one selected from a group consisting of lithium cobalt oxide (LCO), lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminum oxide, and over-lithiated oxide (OLO).
8. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity negative electrode material is at least one selected from a group consisting of amorphous carbon and a graphite-based negative electrode material.
9. The secondary battery according to claim 3 , wherein the relatively low-output, high-capacity negative electrode material is at least one selected from a group consisting of a graphite-based negative electrode material, a silicon (Si)-based negative electrode material, and a tin (Sn)-based negative electrode material.
10. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity positive electrode material and the relatively low-output, high-capacity positive electrode material are identical in kind to each other, and a porosity of the relatively high-output, low-capacity positive electrode material has 110% to 300% of a porosity of the relatively low-output, high-capacity positive electrode material.
11. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity positive electrode material and the relatively low-output, high-capacity positive electrode material are identical in kind to each other, and an amount of the relatively high-output, low-capacity positive electrode material coated on the positive electrode current collector is 50% to 90% of an amount of the relatively low-output, high-capacity positive electrode material coated on the positive electrode current collector.
12. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity negative electrode material and the relatively low-output, high-capacity negative electrode material are identical in kind to each other, and a porosity of the relatively high-output, low-capacity negative electrode material is 110% to 300% of a porosity of the relatively low-output, high-capacity negative electrode material.
13. The secondary battery according to claim 3 , wherein the relatively high-output, low-capacity negative electrode material and the relatively low-output, high-capacity negative electrode material are identical in kind to each other, and an amount of the relatively high-output, low-capacity negative electrode material coated on the negative electrode current collector is 50% to 90% of an amount of the relatively low-output, high-capacity negative electrode material coated on the negative electrode current collector.
14. The secondary battery according to claim 1 , wherein the electrode materials exhibiting different output and capacity properties are different from each other in terms of kind of the electrode materials, a coating method, porosity, a coating amount, or a mixing ratio.
15. The secondary battery according to claim 1 , wherein the positive electrode material or the negative electrode material is at least one selected from among an electrode material for nickel metal hydride secondary batteries, an electrode material for nickel cadmium secondary batteries, and an electrode material for capacitors.
16. The secondary battery according to claim 1 , wherein, when the positive electrode material or the negative electrode material is added to the electrode current collector, an adhesive material for increasing adhesion force between the positive electrode material or the negative electrode material and the electrode current collector is further added to the electrode current collector.
17. The secondary battery according to claim 1 , wherein the electrode assembly is manufactured through a manufacturing process comprising high-temperature, high-pressure pressing.
18. The secondary battery according to claim 1 , wherein the separator comprises one or more kinds of separators.
19. A battery pack comprising a secondary battery according to claim 1 as a unit cell.
20. The battery pack according to claim 19 , wherein the battery pack further comprises a cooling member.
21. A device comprising a battery pack according to claim 19 .
22. The device according to claim 21 , wherein the device is selected from a group consisting of a laptop computer, a mobile phone, a portable display player (PDP), a portable multimedia player (PMP), an MP3 player, a digital still camera (DSC), a digital video recorder (DVR), a smartphone, a global positioning system (GPS), a camcorder, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage device.