Composite materials

1. A composite material comprising:

a first conductive fibrous layer comprising a plurality of electrically conductive fibers;

a second conductive fibrous layer comprising a plurality of electrically conductive fibers;

a resin layer located between said first conductive fibrous layer and said second conductive fibrous layer and defining an average thickness therebetween, said resin layer comprising a polymeric resin, a plurality of thermoplastic toughening particles and a plurality of electrically conductive particles;

wherein at least 50% of said conductive particles have a diameter that is within 10 μm of the average thickness of said resin layer.

2. The composite material of claim 1 , wherein at least 90% of said conductive particles have a diameter between 0.3 μm and 100 μm.

3. The composite material of claim 1 , wherein the diameter of each of said conductive particles is the largest cross-sectional diameter or dimension of a respective particle.

4. The composite material of claim 1 , wherein said conductive particles have an aspect ratio between 1 and 10.

5. The composite material of claim 1 , wherein said conductive particles comprise carbon particles.

6. A composite material comprising:

a first conductive fibrous layer comprising a plurality of electrically conductive fibers;

a second conductive fibrous layer comprising a plurality of electrically conductive fibers;

a resin layer located between said first conductive fibrous layer and said second conductive fibrous layer and defining an average thickness therebetween, said resin layer comprising a polymeric resin, a plurality of thermoplastic toughening particles and a plurality of electrically conductive particles defining an average diameter;

wherein said electrically conductive particles have an average diameter between 0.3 μm and 100 μm, and wherein said resin layer has a average thickness between 10.3 μm and 110 μm.

7. The composite material of claim 6 , wherein at least 90% of said conductive particles have a diameter between 0.3 μm and 100 μm.

8. The composite material of claim 6 , wherein the average diameter of said conductive particles is determined based on the largest cross-sectional diameter or dimension of each of said conductive particles.

9. The composite material of claim 6 , wherein said conductive particles have an aspect ratio between 1 and 10.

10. The composite material of claim 6 , wherein said conductive particles comprise carbon particles.

11. A prepreg comprising:

a conductive fibrous layer comprising a plurality of electrically conductive fibers;

a resin layer located on at least one side of side conductive fibrous layer, said resin layer comprising a polymeric resin, a plurality of thermoplastic toughening particles and a plurality of electrically conductive particles;

wherein said resin layer is configured to join with a corresponding resin layer of an adjoining prepreg and thereby define an interleaf resin layer thickness; and

wherein at least 50% of said conductive particles in said resin layer have a diameter that is within 10 μm of the interleaf resin layer thickness.

12. The prepreg of claim 11 , wherein at least 90% of said conductive particles have a diameter between 0.3 μm and 100 μm.

13. The prepreg of claim 11 , wherein the diameter of each of said conductive particles is the largest cross-sectional diameter or dimension of a respective particle.

14. The composite material of claim 11 , wherein said conductive particles have an aspect ratio between 1 and 10.

15. The composite material of claim 11 , wherein said conductive particles comprise carbon particles.

16. A prepreg comprising:

a conductive fibrous layer comprising a plurality of electrically conductive fibers;

a resin layer located on at least one side of said conductive fibrous layer, said resin layer comprising a polymeric resin, a plurality of thermoplastic toughening particles and a plurality of electrically conductive particles;

wherein said resin layer is configured to join with a corresponding resin layer of an adjoining prepreg and thereby define an interleaf resin layer thickness; and

wherein said electrically conductive particles have an average diameter between 0.3 μm and 100 μm, and wherein said interleaf resin layer has an average thickness between 10.3 μm and 110 μm.

17. The prepreg of claim 16 , wherein at least 90% of said conductive particles have a diameter between 0.3 μm and 100 μm.

18. The prepreg of claim 13 , wherein the diameter of each of said conductive particles is the largest cross-sectional diameter or dimension of a respective particle.

19. The composite material of claim 13 , wherein said conductive particles have an aspect ratio between 1 and 10.

20. The composite material of claim 13 , wherein said conductive particles comprise carbon particles.