1. A system for determining fluid flow of compressible and non-compressible liquids, the system comprising:
input means for receiving a model of an object defined as a plurality of cells having a plurality of nodes P;
a processor coupled to a memory, the processor configured for implementing the steps of:
discretizing a partial differential equation corresponding to the received model of the object;
for each node P in the plurality of nodes P:
i. locating all neighbouring cells that share the node P, each of the neighbouring cells having a cell center;
ii. approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation; and
iii. updating a solution of the partial differential equation at the node P by using the approximated discretized partial differential equation at all the neighbouring cell centers; and
iteratively updating the solution for all the nodes P from an initial guess until a convergence criterion is satisfied.
2. The system of claim 1, wherein in the step of approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation, the processor is further configured for:
calculating the cell centered coordinates of the neighbouring cell and each of the coordinates at w, s, e and n intersections;
calculating a solution of the partial differential equation at each of the w, s, e, and n intersections; and
approximating the partial differential equation at the cell center using the discretized partial differential equation, wherein the discretized partial differential equation includes the calculated solution of the partial differential equation at each of the w, s, e, and n intersections.
3. The system of claim 2, wherein the step of calculating the solution of the partial differential equation at each of the w, s, e, and n intersections by the processor includes a weighted averaging between the neighbouring cells that share the intersection at each of w, s, e, and n.
4. The system of claim 2, wherein the model of the object is in two dimensions.
5. The system of claim 2, wherein the model of the object is in three dimensions and the w, s, e, and n intersections further includes f and b intersections.
6. The system of claim 1, wherein the discretized partial differential equation is a difference equation.
7. The system of claim 1, wherein the updating of the solution of the partial differential equation at the node P by the processor includes weighted averaging of the approximated discretized partial differential equation at all the neighbouring cell centers.
8. A computer-implemented method for approximating a partial differential equation for determining fluid flow of compressible and non-compressible liquids, the method comprising:
discretizing the partial differential equation;
receiving a model of an object defined as a plurality of cells having a plurality of nodes P;
for each node P in the plurality of nodes P:
i. locating all neighbouring cells that share the node P, each of the neighbouring cells having a cell center;
ii. approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation; and
iii. updating a solution of the partial differential equation at the node P by using the approximated discretized partial differential equation at all the neighbouring cell centers; and
iteratively updating the solution for all the nodes P from an initial guess until a convergence criterion is satisfied.
9. The computer-implemented method of claim 8, wherein the step of approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation includes:
calculating the cell centered coordinates of the neighbouring cell and each of the coordinates at w, s, e and n intersections;
calculating a solution of the partial differential equation at each of the w, s, e, and n intersections; and
approximating the partial differential equation at the cell center using the discretized partial differential equation, wherein the discretized partial differential equation includes the calculated solution of the partial differential equation at each of the w, s, e, and n intersections.
10. The computer-implemented method of claim 9, wherein the step of calculating the solution of the partial differential equation at each of the w, s, e, and n intersections includes a weighted averaging between the neighbouring cells that share the intersection at each of w, s, e, and n.
11. The system of claim 9, wherein the model of the object is in two dimensions.
12. The system of claim 9, wherein the model of the object is in three dimensions and the w, s, e, and n intersections further includes f and b intersections.
13. The computer-implemented method of claim 8, wherein the discretized partial differential equation is a difference equation.
14. The computer-implemented method of claim 8, wherein the updating of the solution of the partial differential equation at the node P includes weighted averaging of the approximated discretized partial differential equation at all the neighbouring cell centers.
15. A computer readable medium having instructions stored thereon that when executed by a computer implement a method for approximating a partial differential equation for determining fluid flow of compressible and non-compressible liquids, the method comprising:
discretizing the partial differential equation;
receiving a model of an object defined as a plurality of cells having a plurality of nodes P;
for each node P in the plurality of nodes P:
i. locating all neighbouring cells that share the node P, each of the neighbouring cells having a cell center;
ii. approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation; and
iii. updating a solution of the partial differential equation at the node P by using the approximated discretized partial differential equation at all the neighbouring cell centers; and
iteratively updating the solution for all the nodes P from an initial guess until a convergence criterion is satisfied.
16. A computer readable medium of claim 15, wherein the step of approximating the partial differential equation at the cell center of each of the neighbouring cells using the discretized partial differential equation includes:
calculating the cell centered coordinates of the neighbouring cell and each of the coordinates of w, s, e and n intersections;
calculating a solution of the partial differential equation at each of the w, s, e, and n intersections; and
approximating the partial differential equation at the cell center using the discretized partial differential equation, wherein the discretized partial differential equation includes the calculated solution of the partial differential equation at each of the w, s, e, and n intersections.
17. A computer readable medium of claim 16, wherein the step of calculating the solution of the partial differential equation at each of the w, s, e, and n intersections includes a weighted averaging between the neighbouring cells that share the intersection at each of w, s, e, and n.
18. The system of claim 16, wherein the model of the object is in three dimensions and the w, s, e, and n intersections further includes f and b intersections.
19. A computer readable medium of claim 15, wherein the discretized partial differential equation is a difference equation.
20. A computer readable medium of claim 15, wherein the updating of the solution of the partial differential equation at the node P includes weighted averaging of the approximated discretized partial differential equation at all the neighbouring cell centers.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A packaging for a cable-type secondary battery, surrounding an electrode assembly in the cable-type secondary battery, the packaging having a moisture-blocking layer comprising sealant polymer layers on both outer surfaces of a moisture-blocking film and a moisture-blocking film disposed between the sealant polymer layers,
wherein the moisture-blocking layer is a tube form surrounding the electrode assembly, and the sealant polymer layers in both ends of the moisture-blocking layer are overlapped and adhered with each other in a predetermined part.
2. The packaging according to claim 1, wherein the moisture-blocking layer comprises a metal sheet or a polymer sheet.
3. The packaging according to claim 2, wherein the metal sheet comprises any one selected from the group consisting of iron (Fe), carbon (C), chrome (Cr), manganese (Mn), nickel (Ni), copper (Cu), aluminum (Al), an equivalent thereof and an alloy of two or more thereof.
4. The packaging according to claim 2, wherein the polymer sheet is made of at least one selected from the group consisting of a polyethylene (PE), polypropylene(PP), a polymer clay composite and a liquid crystal polymer.
5. The packaging according to claim 1, wherein the sealant polymer layers comprise any one selected from the group consisting of a copolymer of polypropylene-acrylic acid, a copolymer of polyethylene-acrylic acid, polypropylene chloride, a terpolymer of polypropylene-butylene-ethylene, polypropylene, polyethylene, a copolymer of ethylene-propylene, and a mixture thereof.
6. The packaging according to claim 1, wherein the moisture-blocking layer comprises an adhesive layer between the moisture-blocking film and the sealant polymer layers.
7. The packaging according to claim 1, which further comprises a heat-shrinkable tube that surrounds the outer surface of the moisture-blocking layer.
8. The packaging according to claim 7, wherein the heat-shrinkable tube comprises at least one selected from the group consisting of polyolefins, polyesters, fluoro-containing resins, and polyvinyl chloride (PVC).
9. The packaging according to claim 1, wherein the moisture-blocking layer comprises a mechanical supporting layer on at least one surface between the moisture-blocking film and both sealant polymer layers.
10. The packaging according to claim 9, wherein the moisture-blocking layer has a structure in which a sealant polymer layer, a mechanical supporting layer, a metal sheet of moisture-blocking layer and another sealant polymer layer are laminated in order.
11. The packaging according to claim 9, wherein the mechanical supporting layer is at least one polymer selected from the group consisting of polyolefins, polyesters, polyimides and polyamides.
12. The packaging according to claim 9, wherein the moisture-blocking layer comprises a metal sheet.
13. The packaging according to claim 9, wherein an adhesive layer is further formed between the moisture-blocking film and the mechanical supporting layer.
14. The packaging according to claim 9, which further comprises a heat-shrinkable tube that surrounds the outer surface of the moisture-blocking layer.
15. A cable-type secondary battery, comprising:
an electrode assembly having a horizontal cross section of a predetermined shape and extending longitudinally, which comprises an inner electrode including an inner current collector and an inner electrode active material, a separation layer surrounding the inner electrode to prevent a short circuit between electrodes, and an outer electrode including an outer current collector formed to surround the outer surface of the separation layer and an outer electrode active material; and
the packaging according to claim 1 which surrounds the outer surface of the electrode assembly closely.
16. The cable-type secondary battery according to claim 15, wherein the packaging is formed by closely winding the outer surface of the electrode assembly so that both ends of the electrode assembly are exposed to the outside.
17. The cable-type secondary battery according to claim 15, wherein the inner electrode of the electrode assembly comprises a core for supplying lithium ions, which comprises an electrolyte, at least one wire-form inner current collector that is wound to surround the outer surface of the core for supplying lithium ions, and an inner electrode active material layer.
18. The cable-type secondary battery according to claim 15, wherein the inner electrode has a structure that the inner electrode active material layer is formed on the whole surface of the wire-form inner current collector; or a structure that the inner electrode active material layer is formed to surround the outer surface of the wound wire-form inner current collector.
19. The cable-type secondary battery according to claim 15, wherein the outer electrode is formed in a structure having a sheet-form outer current collector wound to surround the outer surface of the separation layer, and an outer electrode active material layer surrounding the outer surface of the sheet-form outer current collector; a structure having an outer electrode active material layer surrounding the outer surface of the separation layer, and a sheet-form outer current collector wound to surround the outer surface of the outer electrode active material layer; a structure having a sheet-form outer current collector wound to surround the outer surface of the separation layer, and an outer electrode active material layer surrounding the outer surface of the sheet-form outer current collector and coming into contact with the separation layer; or a structure having an outer electrode active material layer surrounding the outer surface of the separation layer, and a sheet-form outer current collector that is included inside the outer electrode active material layer by being covered therein and wound to surround the outer surface of the separation layer with spacing apart therefrom.
20. The cable-type secondary battery according to claim 15, wherein the outer electrode is formed by winding a sheet-form outer electrode to surround the outer surface of the separation layer, the sheet-form outer electrode being formed by the bonding of the outer electrode active material layer and the sheet-form outer current collector.
21. The cable-type secondary battery according to claim 15, wherein the outer electrode is a sheet-form outer electrode which comprises an outer current collector, an outer electrode active material layer formed on one surface of the outer current collector, a conductive layer formed on the top surface of the outer electrode active material layer and comprising a conductive material and a binder, a first porous supporting layer formed on the top surface of the conductive layer, and a second supporting layer formed on the other surface of the outer current collector.
22. The cable-type secondary battery according to claim 15, wherein the outer current collector is in the form of a mesh.
23. The cable-type secondary battery according to claim 15, wherein the electrode assembly comprises a core for supplying lithium ions, which comprises an electrolyte; an inner electrode, comprising one or more wire-form inner current collectors which are wound to surround the outer surface of the core for supplying lithium ions, and an inner electrode active material layer formed on the surface of the wire-form inner current collectors; a separation layer surrounding the outer surface of the inner electrode to prevent a short circuit between electrodes; and a sheet-form outer electrode surrounding the outer surface of the separation layer, and comprising an outer current collector, an outer electrode active material layer formed on one surface of the outer current collector, a conductive layer formed on the top surface of the outer electrode active material layer and comprising a conductive material and a binder, a first porous supporting layer formed on the top surface of the conductive layer, and a second supporting layer formed on the other surface of the outer current collector.
24. The cable-type secondary battery according to claim 15, wherein the inner electrode is an anode or a cathode, and the outer electrode is a cathode or an anode corresponding thereto.
25. The cable-type secondary battery according to claim 15, wherein the separation layer is an electrolyte layer or a separator.
26. A method for preparing a cable-type secondary battery, comprising
(S1) providing an electrode assembly having a horizontal cross section of a predetermined shape and extending longitudinally, which comprises an inner electrode, a separation layer surrounding the inner electrode to prevent a short circuit between electrodes, and an outer electrode surrounding the outer surface of the separation layer;
(S2) providing a moisture-blocking layer having a length longer than the perimeter of the outer surface of the electrode assembly and comprising sealant polymer layers on both outer surfaces of the moisture-blocking film and a moisture-blocking film disposed between the sealant polymer layers;
(S3) surrounding the outer surface of the electrode assembly with the moisture-blocking layer so that the sealant polymer layers in both ends of the moisture-blocking layer are overlapped with each other in a predetermined part; and
(S4) bringing the electrode assembly surrounded with the moisture-blocking layer into heat-treatment, thereby adhering the overlapped part of the sealant polymer layers at both ends of the moisture-blocking layer.
27. The method according to claim 26, wherein the moisture-blocking layer provided in the step (S2) comprises a mechanical supporting layer on at least one surface between the moisture-blocking film and both sealant polymer layers.
28. The method according to claim 26, wherein the moisture-blocking layer provided in the step (S2) has a structure in which a sealant polymer layer, a mechanical supporting layer, a metal sheet of moisture-blocking layer and another sealant polymer layer are laminated in order.
29. The method according to claim 26, wherein the step (S4) further comprises inserting the electrode assembly surrounded with the moisture-blocking layer in a heat-shrinkable tube prior to the heat-treatment, thereby bonding the heat-shrinkable tube to the electrode assembly surrounded with the moisture-blocking layer by the shrinkage of the tube, while adhering the overlapped part of the sealant polymer layers at both ends of the moisture-blocking layer.