Separator for a battery cell and battery cell providing such a separator
The present invention relates to a separator arrangement ( 20 ) for an electrochemical battery cell ( 10 ) comprising an ionically conductive and electrically insulating separator layer ( 22 ), characterized in that the separator arrangement ( 20 ) further comprises a reduction layer ( 24 ) comprising a reductant, wherein the reduction layer ( 24 ) has a specific surface area which is in a range of not less than 10 m 2 /g, preferably of not less than 100 m 2 /g, for example of not less than 1000 m 2 /g, and wherein the reduction layer ( 24 ) is porous and has an open porosity in a range from not less than 10% to not more than 90%, preferably from not less than 30% to not more than 70%.
1. An electrochemical battery cell comprising:
an anode;
a cathode; and
a separator arrangement between the anode and the cathode, the separator arrangement including:
an ionically conductive and electrically insulating separator layer; and
a reduction layer consisting of a reduction material, wherein the reduction layer has a specific surface area which is not less than 10 m 2 /g, and wherein the reduction layer is porous and has an open porosity in a range from not less than 30% to not more than 70%, wherein the reduction layer is made of a reduction material having a redox potential in a range of +0.16 V or less against the standard hydrogen electrode,
wherein the reduction layer is provided with a porous protective layer on a side of the reduction layer opposite the separator layer, and
wherein the protective layer is made of an electrically insulating material.
2. The battery cell as claimed in claim 1 , characterized in that the reduction layer is disposed atop the surface of the separator layer.
3. The battery cell as claimed in claim 1 , characterized in that the reduction layer is positioned between the separator layer and the anode.
4. The battery cell as claimed in claim 1 , characterized in that the battery cell is a lithium-ion cell.
5. The battery cell as claimed in claim 1 , wherein the reduction layer has a specific surface area which is not less than 100 m 2 /g.
6. The battery cell as claimed in claim 1 , wherein the reduction layer has a specific surface area which is not less than 1000 m 2 /g.
7. The battery cell as claimed in claim 1 , wherein the reduction layer is a porous metal layer.
8. The battery cell as claimed in claim 7 , wherein the porous metal layer includes said reduction material selected from the group consisting of aluminum, titanium and nickel.