Nickel zinc battery design
View Patent ↗Nickel zinc cylindrical battery cell designs are described. The designs provided limit dendrite formation and prevent build up of hydrogen gas in the cell. The present invention also provides low-impedance cells required by rapid discharge applications. The cylindrical battery cells may have polarity opposite of that of conventional power cells, with a negative cap and positive can. The cylindrical cells may include a gel electrolyte reservoir.
1. A wound electrode cylindrical nickel zinc battery cell comprising:
a) a negative electrode layer comprising zinc and a negative current collector substrate;
b) a positive electrode layer comprising nickel and a positive current collector substrate;
c) a separator layer to separate the positive electrode layer and the negative electrode layer; and
d) a slotted current collector disk comprising radial open sections that are open at the circumferential edge of the slotted current collector disk and vertical energy directors that make intimate contact with the negative current collector substrate of the wound electrode, wherein one end of the negative current collector substrate is bent to form a substantially flat surface for electrical communication with the slotted current collector disk wherein the negative current collector substrate has material removed at the bend point of the bent end.
2. The battery cell of claim 1 , wherein the negative electrode layer is between 16 and 24 mils thick and the positive electrode layer is between 16 and 24 mils thick.
3. The battery cell of claim 1 , wherein the separator layer comprises a barrier layer and a wetting layer, each made of a different material.
4. The battery cell of claim 1 , wherein the barrier layer and the wetting layer are the same material.
5. The battery cell of claim 3 , wherein the barrier layer is between about 2 and about 4 mils thick.
6. The battery cell of claim 1 , wherein the slotted current collector disk is in electrical communication with the negative current collector substrate, and is copper with one side coated with tin or a tin alloy.
7. The battery cell of claim 1 further comprising an electrolyte, wherein at least some of the electrolyte is in gel form.
8. The battery cell of claim 6 further comprising a can electrically connected to the positive current collector substrate via a positive collector disk interposed between the current collector substrate and the can.
9. The battery cell of claim 8 , wherein the positive current collector disk is perforated.
10. The battery cell of claim 3 , wherein the wetting layer is adjacent to the negative electrode layer and the barrier layer is adjacent to the positive electrode layer.
11. The battery cell claim 1 wherein the overall AC impedance is between about 3 and 5.0 mΩ.
12. The battery cell of claim 1 , wherein the slotted current collector disk further comprises a center hole.
13. The battery cell of claim 1 , wherein the negative current collector substrate comprises a perforated copper sheet.
14. The battery cell of claim 13 , wherein the perforated copper sheet is between about 2 mils and about 5 mils thick.
15. The battery cell of claim 13 , wherein the perforated copper sheet is about 2 mils thick.
16. The battery cell of claim 1 , further comprising a cap and vent mechanism configured to vent at a cell pressure of between about 300 psi and about 600 psi.
17. The battery cell of claim 1 , further comprising a cap and vent mechanism configured to vent at a cell pressure of between about 300 psi and about 450 psi.