Self-centering current collector for an electrochemical cell
View Patent ↗A current collector for an electrode of an electrochemical cell is described. The current collector has a peripheral edge between first and second major faces, the edge comprising at least a first edge contiguous with a second edge angled with respect to each other. A protrusion extends outwardly from the junction of the first and second edges. This protrusion helps to precisely position the current collector in a pressing fixture. That way, active material is contacted to each of the major faces of the current collector and is of a uniform thickness about its edges. Later, when the resulting electrode plate is assembled into an electrochemical cell, such as of a multi-plate construction, the protrusion also serves to maintain strict alignment of the plate inside the casing.
1. A current collector for an electrical energy storage device, the current collector comprising:
a) a first major face;
b) a second major face;
c) a peripheral edge between the first and second major faces, wherein the peripheral edge comprises at least a first edge portion contiguous with a second edge portion angled with respect to each other; and
d) a protrusion extending outwardly from the junction of the first and second edge portions, wherein a first protrusion portion resides between a first imaginary extension of the first edge portion of the current collector and a perimeter of the protrusion and a second protrusion portion resides between a second imaginary extension of the second edge portion of the current collector and the protrusion perimeter so that a first distance from the first imaginary extension to a first distant-most tangent of the protrusion perimeter furthest from the first imaginary extension edge is substantially equal to a second distance from the second imaginary extension to a second distant-most tangent of the protrusion perimeter furthest from the second imaginary extension.
2. The current collector of claim 1 wherein equal portions of the protrusion reside along each of the first and second edge portions.
3. The current collector of claim 1 wherein the first and second edge portions of the current collector are disposed at either a right or an obtuse angle with respect to each other.
4. The current collector of claim 1 wherein the first and second edge portions of the current collector are straight.
5. The current collector of claim 1 wherein at least one of the first and second edge portions of the current collector is curved.
6. The current collector of claim 1 wherein the current collector has at least four edge portions with a protrusion disposed at the junction of each of the contiguous edge portions.
7. An electrochemical cell, which comprises:
a) a first electrode;
b) a second, counter electrode;
c) an electrolyte activating the first and second electrodes; and
d) wherein at least one of the electrodes comprises a current collector comprising:
i) a first major face;
ii) a second major face;
iii) a peripheral edge between the first and second major faces, wherein the edge comprises a first edge portion contiguous with a second edge portion; and
iv) a protrusion extending outwardly from a junction of the first and second edge portions, wherein a first protrusion portion resides between a first imaginary extension of the first edge portion of the current collector and a perimeter of the protrusion and a second protrusion portion resides between a second imaginary extension of the second edge portion of the current collector and the protrusion perimeter so that a first distance from the first imaginary extension to a first distant-most tangent of the protrusion perimeter furthest from the first imaginary extension is substantially equal to a second distance from the second imaginary extension to a second distant-most tangent of the protrusion perimeter furthest from the second imaginary extension.
8. The electrochemical cell of claim 7 wherein equal portions of the protrusion reside along each of the contiguous edge portions.
9. The electrochemical cell of claim 7 wherein the first and second edge portions of the current collector are disposed at either a right or an obtuse angle with respect to each other.
10. The electrochemical cell of claim 7 wherein the current collector has at least four edge portions with a protrusion disposed at the junction of each of the contiguous edge portions.
11. The current collector of claim 1 wherein the protrusion is continuously curved from the first edge portion of the current collector to the second edge portion thereof.