Negative electrodes for use in accumulators operating according to the ion insertion and deinsertion or alloy formation principle and accumulator comprising such an electrode

Patent metadata

Field	Value
Publication number	US-2020220178-A1
Application number	US-202016735081-A
Country	US
Kind code	A1
Filing date	Jan 6, 2020
Priority date	Jan 8, 2019
Publication date	Jul 9, 2020
Grant date	—

Abstract

A negative electrode for an accumulator functioning based on the ion insertion and deinsertion principle and/or based on the alloy formation and dealloying principle, the negative electrode comprising: a first layer comprising an active material deposited via one of its faces, on a first face of a current collector; a second layer comprising an active material deposited via one of its faces, on a second face of a current collector, the first face being opposite the second face; wherein the current collector is provided with through holes connecting the first layer to the second layer and in that the first layer is coated with a layer composed of a metal, the corresponding cations of which are those used in the ion insertion and deinsertion process and/or in the alloy formation and dealloying process in the active material of the first layer and the second layer.

First claim

1 . Negative electrode for an accumulator functioning based on the ion insertion and deinsertion principle and/or based on the alloy formation and dealloying principle, said negative electrode comprising:
a first layer ( 3 ) comprising an active material deposited via one of its faces, on a first face of a current collector ( 5 ); a second layer ( 7 ) comprising an active material deposited via one of its faces, on a second face of a current collector ( 5 ), said first face being opposite said second face; wherein the current collector ( 5 ) is provided with through holes ( 6 ) connecting the first layer to the second layer and in that the first layer is coated with a layer composed of a metal ( 1 ), the corresponding cations of which are those used in the ion insertion and deinsertion process and/or in the alloy formation and dealloying process in the active material of the first layer and the second layer.

2 . Negative electrode according to claim 1 , wherein the active material, either for the first layer and/or the second layer, is chosen from among:
silicon; a carbon material such as hard carbon, natural graphite or artificial graphite; and; mixtures thereof.

3 . Negative electrode according to claim 1 , wherein the active material, either for the first layer and/or the second layer, is tin.

4 . Negative electrode according to claim 1 , wherein the layer composed of a metal ( 1 ) is a layer composed of an alkali metal or a layer composed of an alkali-earth metal.

5 . Negative electrode according to claim 1 , wherein the layer composed of a metal ( 1 ) is in the form of metal foil.

6 . Negative electrode according to claim 1 , wherein the layer composed of a metal ( 1 ) has a thickness greater than or equal to 20 μm.

7 . Negative electrode according to claim 1 , wherein the current collector ( 5 ) comprises one or several metals chosen from among copper, aluminium, nickel and alloys thereof.

8 . Negative electrode according to claim 1 , wherein the first layer ( 3 ) is provided with through holes located along the prolongation of the holes in the current collector.

9 . Negative electrode according to claim 1 , wherein the second layer ( 7 ) is provided with through holes located along the prolongation of the holes in the current collector.

10 . Method of preparing a negative electrode as defined in claim 1 , comprising the following steps:
a) a step to deposit on a first face of a current collector in which there are through holes, a first layer comprising an active material and a second layer comprising an active material on a second face of the current collector, said first face and said second face being opposite each other; b) a step to deposit a layer composed of a metal on the first layer comprising the active material, the corresponding cations of the layer composed of a metal are those involved in the ion insertion or deinsertion process in the active material of the first layer and the second layer or in the alloy formation and dealloying process in the active material of the first layer and the second layer.

11 . Method of preparing a negative electrode as defined in claim 1 , comprising the following steps:
c) a step to deposit a first layer on a current collector, comprising an active material on a first face of an unperforated current collector and a second layer comprising an active material on a second face of the current collector, said first face and said second face being opposite each other; d) a step to apply a perforator on the assembly obtained in step a), to form the collector provided with through holes; e) a step to deposit a layer composed of a metal on the first layer comprising the active material, the corresponding cations of the layer composed of a metal are those involved in the ion insertion and deinsertion process in the active material of the first layer and the second layer or in the alloy formation and dealloying process in the active material of the first layer and the second layer.

12 . Method of activating a negative electrode as defined according to claim 1 , comprising a step to bring the negative electrode into contact with an electrolyte for a fixed duration and at a fixed temperature to cause corrosion of the metal in the layer composed of a metal into metal cations.

13 . Accumulator functioning based on the principle of ion insertion-deinsertion or the alloy formation and dealloying process comprising a negative electrode as defined according to claim 1 .

14 . Accumulator according to claim 13 , that comprises a first cell and a second cell separated from each other by the current collector ( 27 ) of the negative electrode, said first cell containing a positive electrode ( 31 ), a first electrolytic separator ( 29 ) and the first layer ( 21 ) comprising an active material coated with the layer composed of a metal ( 23 ) of the negative electrode ( 20 ), the first electrolytic separator ( 29 ) being arranged sandwiched between the positive electrode ( 31 ) and the layer composed of metal ( 23 ) and said second cell comprising a positive electrode ( 35 ), a second electrolytic separator ( 33 ) and the second layer ( 25 ) comprising an active material of the negative electrode ( 20 ), said second electrolytic separator ( 33 ) being arranged sandwiched between the positive electrode ( 31 ) and the second layer ( 25 ) comprising an active material.

15 . Accumulator functioning based on the principle of ion insertion-deinsertion or the alloy formation and dealloying process comprising a negative electrode obtained after the activation method defined in claim 12 .

16 . Accumulator according to claim 15 , that comprises a first cell and a second cell separated from each other by the current collector ( 27 ) of the negative electrode, said first cell containing a positive electrode ( 31 ), a first electrolytic separator ( 29 ) and the first layer ( 21 ) comprising an active material coated with the layer composed of a metal ( 23 ) of the negative electrode ( 20 ), the first electrolytic separator ( 29 ) being arranged sandwiched between the positive electrode ( 31 ) and the layer composed of metal ( 23 ) and said second cell comprising a positive electrode ( 35 ), a second electrolytic separator ( 33 ) and the second layer ( 25 ) comprising an active material of the negative electrode ( 20 ), said second electrolytic separator ( 33 ) being arranged sandwiched between the positive electrode ( 31 ) and the second layer ( 25 ) comprising an active material.

Assignees

• Commissariat Energie Atomique

Inventors

• Gutel Elise
• Blanc Lionel
• Porcher Willy
• Reynier Yvan

Classifications

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/667 Primary

  in the form of layers, e.g. coatings · CPC title

• H01M4/663

  containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres · CPC title

• H01M4/662

  Alloys (collectors of lead alloys H01M4/685) · CPC title