Separators for three-dimensional batteries

1. An electrode structure comprising a population of electrodes comprising an electrode active material layer and a population of counter-electrodes comprising a counter-electrode active material layer wherein

the population of electrodes is arranged in alternating sequence with the population of counter-electrodes along a first direction,

each member of the electrode population has a bottom, a top, a length L E , a width W E , a height H E , and a longitudinal axis A E extending from the bottom to the top of each such member and in a direction that is transverse to the first direction, the length L E of each member of the electrode population being measured in the direction of its longitudinal axis A E , the width W E of each member of the electrode population being measured in the first direction, and the height H E of each member of the electrode population being measured in a direction that is perpendicular to the longitudinal axis A E of each such member and the first direction, the ratio of L E to each of W E and H E of each member of the electrode population being at least 5:1, respectively, the ratio of H E to W E for each member of the electrode population being between 0.4:1 and 1000:1, respectively, and

the longitudinal axis A E of each member of the population of electrodes is surrounded by an electrically insulating separator layer, the electrically insulating separator layer comprising a microporous separator material having a void fraction of at least 20 vol. % and a second electrically insulating material having a conductivity for lithium of less than 10 −4 S/cm, wherein the microporous separator material is located between members of the electrode and counter-electrode populations and the second electrically insulating material is elsewhere about the longitudinal axis.

2. The electrode structure of claim 1 wherein between members of the electrode population and members of the counter-electrode population the microporous separator material constitutes at least 70 vol % of the electrically insulating separator layer.

3. The electrode structure of claim 1 wherein the microporous separator material surrounds the longitudinal axis A E of each member of electrode population.

4. The electrode structure of claim 1 wherein the microporous separator material surrounds the longitudinal axis A E of each member of electrode population for at least 70% of the length L E of each member of the electrode population.

5. The electrode structure of claim 1 wherein the microporous separator material surrounds the longitudinal axis A E of each member of electrode population including the top of each member of the electrode population.

6. The electrode structure of claim 1 wherein each of the electrode and counter-electrode populations comprise at least 50 members.

7. The electrode structure of claim 1 wherein L E has a value in the range of about 10 mm to about 250 mm, W E has a value in the range of about 0.01 mm to about 2.5 mm, H E has a value in the range of about 0.05 mm to about 10 mm.

8. The electrode structure of claim 1 wherein the ratio of L E to each of W E and H E for each member of the electrode population is at least 10:1, respectively.

9. The electrode structure of claim 1 wherein a cross-section of each member of the electrode population has a perimeter P E and the ratio of L E to P E for each member of the electrode population is at least 1.25:1, respectively.

10. The electrode structure of claim 1 wherein each member of the counter-electrode population comprises a bottom, a top, a length L CE , a width W CE , a height H CE , and a longitudinal axis A CE extending from the bottom to the top of each such member and in a direction that is transverse to the first direction, the length L CE of each member of the electrode population being measured in the direction of its longitudinal axis A CE , the width W CE of each member of the electrode population being measured in the first direction, and the height H CE of each member of the electrode population being measured in a direction that is perpendicular to the longitudinal axis A CE of each such member and the first direction, the ratio of L CE to each of W CE and H CE of each member of the electrode population being at least 5:1, respectively, the ratio of H CE to W CE for each member of the electrode population being between 0.4:1 and 1000:1, respectively.

11. The electrode structure of claim 1 wherein L CE has a value in the range of about 10 mm to about 250 mm, W CE has a value in the range of about 0.01 mm to about 2.5 mm, and H CE has a value in the range of about 0.05 mm to about 10 mm.

12. The electrode structure of claim 1 wherein the ratio of L CE to each of W CE and H CE for each member of the electrode population is at least 10:1, respectively.

13. The electrode structure of claim 1 wherein a cross-section of each member of the counter-electrode population has a perimeter P CE and the ratio of L CE to P CE for each member of the counter-electrode population is at least 1.25:1, respectively.

14. The electrode structure electrode of claim 1 wherein the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached.

15. The electrode structure of claim 1 wherein the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached and a counter-electrode substrate having a surface to which each member of the counter-electrode population is attached, the electrode substrate surface and the counter-electrode substrate surface being opposing surfaces that are substantially parallel to the first direction.

16. The electrode structure of claim 1 wherein the population of electrodes further comprise an electrode current collector layer, the population of electrodes is a population of negative electrodes, the population of counter-electrodes is a population of positive electrodes, the electrode active material layer is a negative electrode active material layer and the electrode current conductor layer is a negative electrode current conductor layer.

17. The electrode structure of claim 16 wherein the negative electrode active material layer comprises carbon, aluminum, tin, silicon or an alloy thereof.

18. The electrode structure of claim 16 wherein the negative electrode active material layer comprises silicon or an alloy thereof.

19. The electrode structure of claim 1 wherein the population of electrodes is a population of negative electrodes, the population of counter-electrodes is a population of positive electrodes, each member of the population of negative electrodes comprises a negative electrode active material layer and a negative electrode current conductor layer, each member of the population of negative electrodes has a bottom, a top, a length L NE , a width W NE and a height H NE , the length L NE being measured from the bottom to the top of each such negative electrode, the width W NE and the height H NE being measured in directions that are perpendicular to each other and to the direction of measurement of the length L NE , the ratio of L NE to each of W NE and H NE being at least 5:1, respectively, the ratio of H NE to W NE being between 0.4:1 and 1000:1, the negative electrode current collector layer of each member of the population having a length L NC that is measured in the same direction as and is at least 50% Of L NE .

20. The electrode structure of claim 1 wherein the population of electrodes is a population of positive electrodes, the population of counter-electrodes is a population of negative electrodes, each member of the population of positive electrodes comprises a positive electrode active material layer and a positive electrode current conductor layer, each member of the population of positive electrodes has a bottom, a top, a length L PE , a width W PE and a height H PE , the length L PE being measured from the bottom to the top of each such positive electrode, the width W PE and the height H PE being measured in directions that are perpendicular to each other and to the direction of measurement of the length L PE , the ratio of L PE to each of W PE and H PE being at least 5:1, respectively, the ratio of H PE to W PE being between 0.4:1 and 1000:1, respectively, the positive electrode current collector layer of each member of the positive population having a length L PC that is measured in the same direction as and is at least 50% of L PE .

21. A secondary battery comprising a battery enclosure, a non-aqueous electrolyte and an electrode structure of claim 1 .

22. The electrode structure of claim 1 wherein each of the electrode and counter-electrode populations comprise at least 10 members, L E has a value in the range of about 10 mm to about 250 mm, W E has a value in the range of about 0.01 mm to about 2.5 mm, H E has a value in the range of about 0.05 mm to about 10 mm, and the ratio of L E to each of W E and H E for each member of the electrode population is at least 10:1, respectively.

23. The electrode structure of claim 22 wherein a cross-section of each member of the electrode population has a perimeter P E and the ratio of L E to P E for each member of the electrode population is at least 1.25:1, respectively.

24. The electrode structure electrode of claim 22 wherein the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached.

25. The electrode structure of claim 22 wherein the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached and a counter-electrode substrate having a surface to which each member of the counter-electrode population is attached, the electrode substrate surface and the counter-electrode substrate surface being opposing surfaces that are substantially parallel to the first direction.

26. The electrode structure of claim 25 wherein the population of electrodes further comprises an electrode current conductor layer, the population of electrodes is a population of negative electrodes, the population of counter-electrodes is a population of positive electrodes, the electrode active material layer is a negative electrode active material layer and the electrode current collector layer is a negative electrode current collector layer.

27. The electrode structure of claim 26 wherein the negative electrode active material layer comprises carbon, aluminum, tin, silicon or an alloy thereof.

28. The electrode structure of claim 26 wherein the negative electrode active material layer comprises silicon or an alloy thereof.

29. The electrode structure of claim 28 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −5 S/CM.

30. The electrode structure of claim 28 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −6 S/cm.

31. The electrode structure of claim 1 wherein each of the electrode and counter-electrode populations comprise at least 10 members, L E has a value in the range of about 10 mm to about 250 mm, W E has a value in the range of about 0.01 mm to about 2.5 mm, H E has a value in the range of about 0.05 mm to about 10 mm, and the ratio of LE to each of W E and H E for each member of the electrode population is at least 10:1, respectively, the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached, the population of electrodes further comprises an electrode current conductor layer, the population of electrodes is a population of negative electrodes, the population of counter-electrodes is a population of positive electrodes, the electrode active material layer is a negative electrode active material layer and the electrode current collector layer is a negative electrode current collector layer.

32. The electrode structure of claim 31 wherein the negative electrode active material layer comprises silicon or an alloy thereof.

33. The electrode structure of claim 32 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −5 S/CM.

34. The electrode structure of claim 32 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −6 S/cm.

35. The electrode structure of claim 31 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −5 S/CM.

36. The electrode structure of claim 31 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −6 S/cm.

37. The electrode structure of claim 31 wherein the electrode structure further comprises an electrode substrate having a surface to which each member of the electrode population is directly attached and a counter-electrode substrate having a surface to which each member of the counter-electrode population is attached, the electrode substrate surface and the counter-electrode substrate surface being opposing surfaces that are substantially parallel to the first direction.

38. The electrode structure of claim 37 wherein the negative electrode active material layer comprises silicon or an alloy thereof.

39. The electrode structure of claim 37 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −5 S/CM.

40. The electrode structure of claim 37 wherein the second electrically insulating material has a conductivity for lithium of less than 10 −6 S/cm.