Device for storing electric power comprising a protective barrier layer for the collector
The invention concerns a device for storing electric power and method for assembling the device. The device includes an electrode layer and a collector layer associated with the electrode layer, a barrier layer made of metal nitride, the barrier layer being interposed between the electrode layer and the collector layer. The barrier layer is adapted to prevent diffusion of ions contained in an electrolyte up to the collector layer.
1. A power storage device including an electrode layer ( 3 , 5 , 9 , 11 ) and a collector layer ( 1 , 7 ) associated with the electrode layer, comprising:
a barrier layer ( 2 , 6 , 8 , 12 ) formed from a metallic nitride, the barrier layer ( 2 , 6 , 8 , 12 ) being inserted between the electrode layer ( 3 , 5 , 9 , 11 ) and the collector layer ( 1 , 7 ), the barrier layer ( 2 , 6 , 8 , 12 ) being adapted to prevent diffusion of ions contained in an electrolyte ( 13 , 14 , 16 ) up to the collector layer ( 1 , 7 ),
wherein the barrier layer ( 2 , 6 , 8 , 12 ) formed from metallic nitride MeN x , in which Me is at least one metal, has a stoichiometry x of between 0.85 and 1.05, a grain size of between 10 and 30 nanometers, and a thickness of between 0.15 and 0.30 micrometers.
2. The device according to claim 1 , wherein the barrier layer ( 2 , 6 , 8 , 12 ) is formed from titanium nitride (TiN), chromium nitride (CrN) or titanium nitride-aluminium (TiAlN).
3. The device according to claim 1 , wherein the barrier layer ( 2 , 6 , 8 , 12 ) has a columnar structure.
4. The device according to claim 3 , wherein the barrier layer ( 2 , 6 , 8 , 12 ) is formed by reactive magnetron sputtering or by reactive evaporation by plasma-activated electron gun.
5. The device according to claim 1 , wherein the barrier layer ( 2 , 6 , 8 , 12 ) has a granular structure.
6. The device according to claim 5 , wherein the barrier layer is formed by reactive arc evaporation or by reactive electron-gun evaporation without plasma activation.
7. A method for a power storage device assembly including an electrode layer ( 3 , 5 , 9 , 11 ) and a collector layer ( 1 , 7 ) associated with the electrode layer ( 3 , 5 , 9 , 11 ), comprising:
selecting grain-size, thickness and stoichiometry parameters of a barrier layer ( 2 , 6 , 8 , 12 ) in accordance with a lifetime sought for the power storage device,
inserting the barrier layer ( 2 , 6 , 8 , 12 ), formed from metallic nitride, between the electrode layer ( 3 , 5 , 9 , 11 ) and the collector layer ( 1 , 7 ), the barrier layer ( 2 , 6 , 8 , 12 ) being adapted to prevent diffusion of ions contained in an electrolyte ( 13 , 14 , 16 ) up to the collector layer ( 1 , 7 ),
wherein the barrier layer ( 2 , 6 , 8 , 12 ) is formed from metallic nitride MeN x , in which Me is one or more metals, has a stoichiometry x of between 0.85 and 1.05, a grain size of between 10 and 30 nanometers, and a thickness of between 0.15 and 0.30 micrometers.
8. The method according to claim 7 , further comprising forming the barrier layer ( 2 , 6 , 8 , 12 ) by deposition onto a surface of the collector layer ( 1 , 7 ).
9. The method according to claim 7 , further comprising forming the barrier layer ( 2 , 6 , 8 , 12 ) by deposition onto a surface of the electrode layer ( 3 , 5 , 9 , 11 ).
10. The method according to claim 7 , further comprising a preliminary step ( 100 ) of scouring a surface of the collector layer ( 1 , 7 ) intended to be in contact with the barrier layer ( 2 , 6 , 8 , 12 ).
11. The method according to claim 7 , further comprising forming the barrier layer ( 2 , 6 , 8 , 12 ) by reactive magnetron sputtering, by reactive evaporation by plasma-activated electron gun, by reactive arc evaporation or by reactive electron-gun evaporation without plasma activation.