Semi-solid electrodes having high rate capability
Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode and a semi-solid cathode. The semi-solid cathode includes a suspension of an active material of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte. An ion-permeable membrane is disposed between the anode and the semi-solid cathode. The semi-solid cathode has a thickness of about 250 μm to about 2,000 μm, and the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/4. In some embodiments, the semi-solid cathode slurry has a mixing index of at least about 0.9.
1. An electrochemical cell, comprising:
an anode;
a semi-solid cathode including a suspension of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte; and
an ion-permeable membrane disposed between the anode and the semi-solid cathode,
wherein, the semi-solid cathode has a thickness in the range of about 250 μm to about 2,000 μm, and
wherein the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/4.
2. The electrochemical cell of claim 1 , wherein the semi-solid cathode has an electronic conductivity of at least about 10 −3 S/cm.
3. The electrochemical cell of claim 1 , wherein the semi-solid cathode has an area specific capacity of at least about 8 mAh/cm 2 at a C-rate of C/4.
4. The electrochemical cell of claim 3 , wherein the semi-solid cathode has an area specific capacity of at least about 9 mAh/cm 2 at a C-rate of C/4.
5. The electrochemical cell of claim 4 , wherein the semi-solid cathode has an area specific capacity of at least about 10 mAh/cm 2 at a C-rate of C/4.
6. The electrochemical cell of claim 1 , wherein the active material in the semi-solid cathode is about 50% to about 75% by volume.
7. The electrochemical cell of claim 6 , wherein the active material in the semi-solid cathode is about 60% to about 75% by volume.
8. The electrochemical cell of claim 1 , wherein the conductive material in the semi-solid cathode is about 1% to about 6% by volume.
9. The electrochemical cell of claim 1 , wherein the semi-solid cathode suspension has a mixing index of at least about 0.90.
10. An electrochemical cell, comprising:
a semi-solid anode including a suspension of about 35% to about 75% by volume of a first active material and about 0% to about 10% by volume of a first conductive material in a first non-aqueous liquid electrolyte;
a semi-solid cathode including a suspension of about 35% to about 75% by volume of a second active material and about 0.5% to about 8% by volume of a second conductive material in a second non-aqueous liquid electrolyte; and
an ion-permeable membrane disposed between the semi-solid anode and the semi-solid cathode,
wherein, the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 250 μm to about 2,000 μm, and
wherein the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/4.
11. The electrochemical cell of claim 10 , wherein the semi-solid cathode has an area specific capacity of at least about 8 mAh/cm 2 at a C-rate of C/4.
12. The electrochemical cell of claim 11 , wherein the semi-solid cathode has an area specific capacity of at least about 9 mAh/cm 2 at a C-rate of C/4.
13. The electrochemical cell of claim 12 , wherein the semi-solid cathode has an area specific capacity of at least about 10 mAh/cm 2 at a C-rate of C/4.
14. The electrochemical cell of claim 10 , wherein the first conductive material in the semi-solid anode is about 0.5% to about 2% by volume.
15. The electrochemical cell of claim 10 , wherein the second active material in the semi-solid cathode is about 50% to about 75% by volume.
16. An electrochemical cell comprising:
an anode;
a semi-solid cathode including a suspension of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte; and
an ion-permeable membrane disposed between the anode and the semi-solid cathode,
wherein, the semi-solid cathode has a thickness in the range of about 250 μm to about 2,000 μm, and
wherein the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/2.
17. The electrochemical cell of claim 16 , wherein the semi-solid cathode has an area specific capacity of at least about 8 mAh/cm 2 at a C-rate of C/2.
18. The electrochemical cell of claim 17 , wherein the semi-solid cathode has an area specific capacity of at least about 9 mAh/cm 2 at a C-rate of C/2.
19. The electrochemical cell of claim 18 , wherein the semi-solid cathode has an area specific capacity of at least about 10 mAh/cm 2 at a C-rate of C/2.
20. The electrochemical cell of claim 16 , wherein the semi-solid cathode suspension has a mixing index of at least about 0.90.
21. An electrochemical cell, comprising:
a semi-solid anode including a suspension of about 35% to about 75% by volume of a first active material and about 0% to about 10% by volume of a first conductive material in a first non-aqueous liquid electrolyte;
a semi-solid cathode including a suspension of about 35% to about 75% by volume of a second active material and about 0.5% to about 8% by volume of a second conductive material in a second non-aqueous liquid electrolyte; and
an ion-permeable membrane disposed between the semi-solid anode and the semi-solid cathode,
wherein, the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 250 μm to about 2,000 μm, and
wherein the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/2.
22. The electrochemical cell of claim 21 , wherein the electrochemical cell has an area specific capacity of at least about 7 mAh/cm 2 at a C-rate of C/4.
23. The electrochemical cell of claim 22 , wherein the electrochemical cell has an area specific capacity of at least about 8 mAh/cm 2 at a C-rate of C/4.
24. The electrochemical cell of claim 21 , wherein the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 250 μm to about 600 μm.
25. The electrochemical cell of claim 24 , wherein the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 300 μm to about 600 μm.
26. The electrochemical cell of claim 25 , wherein the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 350 μm to about 600 μm.
27. The electrochemical cell of claim 26 , wherein the semi-solid anode and the semi-solid cathode each have a thickness in the range of about 400 μm to about 600 μm.
28. The electrochemical cell of claim 21 , wherein the first conductive material in the semi-solid anode is about 0.5% to about 2% by volume.
29. The electrochemical cell of claim 21 , wherein the second active material in the semi-solid cathode is about 50% to about 75% by volume.