Flat heating element

1. A heating element for heating user-contacted surfaces of a passenger compartment of a vehicle, comprising:

at least one electrical conductor including at least one strand,

wherein an electrical conductivity of at least one of the at least one electrical conductors is irreversibly reduced if a temperature thereof at least locally exceeds a permissible maximum temperature,

wherein the heating element includes at least one electric cut-out formed by at least one of the at least one electrical conductors and which interrupts an operating current in the event of a malfunction

wherein the at least one electrical conductor includes at least one internal strand with a thickness of less than 500 μm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

2. A heating element for heating user-contacted surfaces of a passenger compartment of a vehicle, comprising:

at least one electrical conductor including at least one strand,

wherein an electrical conductivity of at least one of the at least one electrical conductors is irreversibly reduced if a temperature thereof at least locally exceeds a permissible maximum temperature,

wherein the electrical conductivity of the at least one electrical conductor is at least temporarily reduced if the temperature thereof, at least locally, is between 200° C. and 400° C.

3. A heating element for heating user-contacted surfaces of a passenger compartment of a vehicle, comprising:

at least one electrical conductor including at least one strand,

wherein an electrical conductivity of at least one of the at least one electrical conductors is irreversibly reduced if a temperature thereof at least locally exceeds a permissible maximum temperature,

wherein the at least one electrical conductor includes at least one conductor support and, arranged thereon, an electrically conductive conducting layer.

4. A heating element for heating user-contacted surfaces of a passenger compartment of a vehicle, comprising:.

at least one electrical conductor including at least one strand,

wherein an electrical conductivity of at least one of the at least one electrical conductors is irreversibly reduced if a temperature thereof at least locally exceeds a permissible maximum temperature,

wherein the at least one electrical conductor includes at least one conductor support, which includes a material into which electrically conductive particles are embedded.

5. The heating element of claim 4 , wherein up to temperatures of at least 150° C., the material of the conductor support retains its chemical and/or mechanical stability to a degree that at least resembles its stability and/or standard conditions.

6. The heating element of claim 2 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of less than 500 μm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

7. The heating element of claim 3 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of less than 500 μm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

8. The heating element of claim 4 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of less than 500 μm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

9. The heating element of claim 2 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of between 100 μm and 100 nm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

10. The heating element of claim 3 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of between 100 μm and 100 nm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

11. The heating element of claim 4 , wherein the at least one electrical conductor includes at least one internal strand with a thickness of between 100 μm and 100 nm, and the at least one internal strand includes at least one coating layer which is less than 1 μm thick and at least partially encases the at least one internal strand.

12. The heating element of claim 1 , wherein the at least one electrical conductor has an electrical resistance between about 100 Ω/m and 1000 Ω/m.

13. The heating element of claim 2 , wherein the at least one electrical conductor has an electrical resistance between 100 Ω/m and 800 Ω/m.

14. The heating element of claim 12 , wherein the at least one electrical conductor is a copper or a copper alloy which is coated with a non-oxidizing metal.

15. The heating element of claim 9 , wherein the at least one electrical conductor is a copper or a copper alloy which is coated with sliver or a sliver alloy.

16. The heating element of claim 10 , wherein the at least one electrical conductor is a copper or a copper alloy which is coated with sliver or a sliver alloy.

17. The heating element of claim 11 , wherein the at least one electrical conductor is a copper or a copper alloy which is coated with sliver or a sliver alloy.

18. The heating element of claim 14 , wherein the at least one electrical conductor includes at least one conductor support having a matrix of fibers, the fibers being made of carbon, steel, graphite, or other metals.

19. The heating element of claim 15 , wherein the at least one electrical conductor includes at least one conductor support, the at least one conductor support including carbon nanotubes having:

a) a diameter that ranges from 1 to 50 nm and

b) a density of 1.3 to 1.4 g/cm3.

20. The heating element of claim 14 , wherein the at least one electrical conductor includes at least one conductor support having a thickness of between about 100 μm and 2 μm.