Method for manufacturing a treated support for a battery

Abstract

The present invention relates to a method for manufacturing a treated support for a battery, the method comprising the following steps: a) depositing, on at least part of the surface of a support for a battery, at least one first layer made of an inorganic material; b) depositing, on at least part of the surface of the first layer, at least one second layer made of a material of formula (I): MFx (I); c) bringing at least one lithium salt of a polymer into contact with the second layer, the polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group, so as to form a third layer located on the second layer.

Description

[0001] Method for manufacturing a treated battery holder

[0002] technical field

[0003] The present invention relates to the field of batteries. More particularly, the present invention relates to a method for manufacturing a treated battery support. The invention also relates to said treated battery support. The present invention further relates to a battery cell comprising said treated battery support or the treated battery support obtainable by the manufacturing method according to the invention, a battery comprising said battery cell, and a device comprising said battery.

[0004] Previous techniques

[0005] An electrochemical cell of an electric battery comprises a positive electrode called the "cathode", a negative electrode called the "anode", an electrolyte allowing the circulation of ions between the anode and the cathode, and anodic and cathodic current collectors carrying, respectively, the anode and the cathode and connecting them to the external circuit.

[0006] The performance of a battery depends on its ionic and electronic transport properties.

[0007] Thermodynamic reactions are initiated during the first charging cycle of the electrochemical cell, and the first ion exchanges between the electrodes take place. Products resulting from these reactions accumulate on the surface of the electrodes to form a layer called the solid-electrolyte interface, or SEI layer.

[0008] In batteries, for example lithium-ion batteries, this layer is an essential element for the proper functioning of the electric battery because it conducts lithium ions very well and has the advantage of stopping the catalytic decomposition of the liquid electrolyte solvent.

[0009] The quality of the SEI layer determines the battery's lifespan, and its formation is therefore an important step.

[0010] The quality of another layer within the battery also affects the battery's lifespan. This is the passivation layer.

[0011] In recent years, artificial passivation layers have been the subject of extensive research. Indeed, it has been discovered that these artificial passivation layers are one of the most promising ways to increase battery life.

[0012] In particular, the passivation layer in an MF-based material XM, broadly denoting a metallic element, and x being at least 2, applied by an atomic layer deposition (ALD) process, is a thin, uniform layer that improves the chemical and electrochemical stability of battery components without significant loss of electrical conductivity. This was described, for example, in US patent application 2018 / 233770.

[0013] However, this passivation layer is very thin and poorly tolerates the inevitable volume changes that occur during battery charge and discharge cycles. This leads to the appearance of surface defects and undesirable reactions (including chemical and / or electrochemical decomposition) that accumulate at the defect sites, resulting in a reduction of battery lifespan.

[0014] Other avenues have been explored, but none of them are entirely satisfactory.

[0015] Thus, there is a need to develop a manufacturing process for a treated battery support that avoids chemical and / or electrochemical decomposition reactions, with the aim of improving battery life.

[0016] Description of the invention

[0017] The invention therefore relates to a method for manufacturing a treated battery support comprising the following steps: a) depositing at least one first layer of an inorganic material onto at least a portion of the surface of a battery support; b) depositing at least one second layer of a material of formula (I): MF onto at least a portion of the surface of said first layer X (I), in which:

[0018] M represents at least one element selected from the alkaline earth metals, transition metals, post-transition metals, and metalloids, and x is an integer at least equal to 2; (c) contact at least one lithium salt of polymer, said polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group, with said second layer to form a third layer situated on the second layer.

[0019] The manufacturing process for the treated battery support according to the invention provides excellent chemical / electrochemical stability on the surface of the third layer. Consequently, the resulting treated battery support is tolerant of volume changes during battery charge and discharge cycles, as well as temperature variations. Thus, the manufacturing process according to the invention improves battery lifespan. The invention also relates to a treated battery support. Another object of the invention is a battery cell comprising at least one treated battery support according to the invention or obtainable by the manufacturing process of the treated battery support according to the invention, a battery comprising at least one battery cell according to the invention, and a device comprising at least one battery according to the invention.

[0020] Other advantages and features of the invention will become more apparent upon examination of the detailed description.

[0021] It is specified that the expression "from... to..." used in this description of the invention should be understood as including each of the limits mentioned.

[0022] As stated above, the manufacturing process for the treated battery support according to the invention comprises: a) depositing on at least a part of the surface of a battery support at least a first layer of an inorganic material.

[0023] Advantageously, the battery support is an anodic current collector, a cathodic current collector, a negative electrode or a positive electrode.

[0024] In a particularly preferred manner, the battery support is a cathode current collector.

[0025] An example of a cathode ray current collector is a sheet of aluminum.

[0026] According to a preferred embodiment, the first layer is deposited over the entire surface of said battery support.

[0027] Advantageously, the inorganic material is chosen from Al2O3, Al, AlFyOz, in which 0 < y / z < 2 / 3, aluminum alloys, preferably Al2O3.

[0028] The said first layer of an inorganic material can be deposited by any technique known to a person skilled in the art, for example by an atomic layer deposition (ADD) process, or by chemical vapor deposition (CVD).

[0029] The manufacturing process for the treated battery support according to the invention also comprises: b) depositing on at least a portion of the surface of said first layer at least a second layer of a material of formula (I): MF X (I), in which:

[0030] M represents at least one element chosen from the alkaline earth metals, transition metals, post-transition metals, and metalloids, and x is an integer at least equal to 2. Advantageously, M is chosen from Al, Mg, Ca, Cu, Cd, Fe, Mn, Ni, Pb, Sn, Sr, Xe, Zn, Al, B, Bi, Ce, Cr, Fe, In, La, Mn, Nd, VO, Y, Ce, Ge, Hf, Si, Sn, Ti, V, Zr, V, Nb, Sb, Ta, Bi, Mo, Re, S and W.

[0031] In a particularly preferred manner, M denotes Al.

[0032] According to a particular embodiment, x ranges from 2 to 6.

[0033] In a particularly preferred manner, x equals 3.

[0034] According to a preferred embodiment, the material of formula (I): MF X (I) is chosen from AIF3, MgF2, CaF2, CuF2, CdF2, FeF2, MnF2, NiF2, PbF2, SnF2, SrF2, XeF2, ZnF2, BF3, BiFs, CeFs, CrFs, FeFs, InFs, LaFs, MnFs, NdFs, VOF3, YF3, CeF4, GeF4, HfF4, SiF4, SnF4, TiF4, VF4, ZrF4, VF5, NbF5, SbF5, TaF5, BiFs, MoF6, ReF6, SF6, WF6 and their composites.

[0035] In a particularly preferred manner, the material of formula (I): MF X (I) is the AIF3 material.

[0036] According to a preferred embodiment, the second layer is deposited over the entire surface of said first layer.

[0037] Said second layer made of a material of formula (I): MF X (I), can be deposited by any technique known to a person skilled in the art, for example by an atomic thin film deposition process or by chemical vapor deposition.

[0038] The manufacturing process for the treated battery support according to the invention also includes: c) contacting at least one lithium salt of polymer, said polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group, with said second layer to form a third layer located on the second layer.

[0039] In this step c), a lithium salt of polymer is brought into contact with the material of the second layer, i.e. the material of formula (I): MF X (I), as defined above.

[0040] The lithium source can be lithium hydroxide.

[0041] Advantageously, the polymer is chosen from polyacrylic acid and polyalcohols, preferably polyacrylic acid.

[0042] A reaction then takes place between the lithium salt of the polymer and the MF material. X, at the end of which a complexing agent can be obtained. Indeed, M can then be linked to a hydroxyl group and / or at least one carboxylic acid group of the polymer to form a complexing agent. In parallel, lithium fluoride (LiF) is also produced.

[0043] Thus, the third layer is made of a material comprising lithium fluoride LiF and at least one compound obtained from the reaction between a lithium polymer salt and the material of formula (I): MF X (I). The compound obtained from the said reaction has the advantage of having a chelating effect. The lithium fluoride LiF obtained also has the advantage of being electrochemically stable and insoluble in conventional electrolytes.

[0044] Therefore, a double passivation layer is obtained on the first layer, which is made of an inorganic material. This double passivation layer, thanks to the nature of the compounds present, provides excellent chemical and electrochemical stability on the surface of the third layer.

[0045] The said third layer can be deposited by any technique known to a person skilled in the art, for example by a sol-gel method or by spraying.

[0046] The invention also relates to a treated battery support comprising:

[0047] - at least a first layer located on at least part of the surface of said battery support made of an inorganic material;

[0048] - at least a second layer located on at least part of the surface of the first layer, made of a material of formula (I): MF X (I), in which:

[0049] M represents at least one element chosen from the alkaline earth metals, transition metals, post-transition metals, and metalloids, and x is an integer at least equal to 2;

[0050] - at least one third layer made of a material comprising lithium fluoride and at least one compound obtained as a result of the reaction between a lithium polymer salt and the material of formula (I): MF X (I), said polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group.

[0051] Preferably, the various embodiments described above for the manufacturing process of the treated battery support are also valid for the treated battery support, where applicable.

[0052] Another object of the invention is a battery cell comprising at least one treated battery support according to the invention or capable of being obtained by the manufacturing process of the treated battery support according to the invention, preferably obtained by the manufacturing process of the treated battery support according to the invention.

[0053] Another object of the present invention is a battery comprising at least one battery cell as defined above.

[0054] The present invention also relates to a device comprising at least one battery as defined above.

[0055] The device in question may be any system incorporating a battery, such as, for example, an electric or electrified vehicle, including a bus, scooter, motorcycle, electronic device, or portable device. The present invention is illustrated, without limitation, by the following examples.

[0056] Examples

[0057] An example of a cathode current collector is an aluminum foil, which is used in the following below.

[0058] A first layer of alumina is then deposited on the surface of the aluminum sheet by any technique known to those skilled in the art, in particular by an atomic thin film deposition process.

[0059] Then, a second AIF3 layer is deposited on the surface of the first alumina layer. This second AIF3 layer is deposited using any technique known to those skilled in the art, including atomic thin-film deposition.

[0060] A lithium salt of polyacrylic acid is then brought into contact with said second layer.

[0061] The lithium salt of polyacrylic acid is obtained through a reaction involving lithium hydroxide and polyacrylic acid in aqueous solution. At the end of the reaction, the lithium salt of polyacrylic acid is purified by recrystallization.

[0062] Lithium polyacrylic acid salt, in aqueous solution, is then sprayed onto the surface of the second layer. The water is rapidly removed after spraying by vacuuming, applying heat, or hot pressing.

[0063] Thus, the lithium salt of polyacrylic acid is brought into contact with the second layer in AIF3, and a reaction occurs.

[0064] Lithium fluoride (LiF) and a complexing agent are thus obtained. Indeed, since aluminum can coordinate with multiple oxygen atoms in the lithium salt of polyacrylic acid, it can act as a crosslinking agent. The complexing agent has the advantage of a chelating effect. Lithium fluoride, for its part, has the advantage of being electrochemically stable and insoluble in conventional electrolytes.

[0065] Therefore, a double passivation layer is formed on the first alumina layer. Thanks to the nature of the compounds present, this double passivation layer provides excellent chemical and electrochemical stability on the surface of the third layer, making the resulting treated battery support tolerant to volume changes during battery charge and discharge cycles. Thus, this double passivation layer improves battery lifespan.

Claims

DEMANDS 1. A method for manufacturing a treated battery support comprising the following steps: a) depositing on at least a portion of the surface of a battery support at least one first layer of an inorganic material; b) depositing on at least a portion of the surface of said first layer at least one second layer of a material of formula (I): MF X (I), in which: M represents at least one element selected from the alkaline earth metals, transition metals, post-transition metals, and metalloids, and x is an integer at least equal to 2; (c) contact at least one lithium salt of polymer, said polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group, with said second layer to form a third layer situated on the second layer.

2. Method according to claim 1, characterized in that the battery support is an anodic current collector, a cathodic current collector, a negative electrode or a positive electrode.

3. A process according to claim 1 or 2, characterized in that the inorganic material is selected from Al2O3, Al, AlF y O z , in which 0 < y / z < 2 / 3, aluminum alloys, preferably Al2O3.

4. Method according to claim 1 or 2, characterized in that M is chosen from Al, Mg, Ca, Cu, Cd, Fe, Mn, Ni, Pb, Sn, Sr, Xe, Zn, Al, B, Bi, Ce, Cr, Fe, In, La, Mn, Nd, VO, Y, Ce, Ge, Hf, Si, Sn, Ti, V, Zr, V, Nb, Sb, Ta, Bi, Mo, Re, S and W.

5. A method according to any one of the preceding claims, characterized in that x goes from 2 to 6.

6. A process according to any one of the preceding claims, characterized in that the polymer is selected from polyacrylic acid and polyalcohols, preferably polyacrylic acid.

7. Treated battery support including: - at least a first layer located on at least part of the surface of said battery support made of an inorganic material; - at least a second layer located on at least part of the surface of the first layer, made of a material of formula (I): MF X (I), in which: M represents at least one element chosen from the alkaline earth metals, transition metals, post-transition metals, and metalloids, and x is an integer at least equal to 2; - at least one third layer made of a material comprising lithium fluoride and at least one compound obtained as a result of the reaction between a lithium polymer salt and the material of formula (I): MF X (I), said polymer comprising at least one hydroxyl group and / or at least one carboxylic acid group.

8. Battery cell comprising at least one treated battery support as defined in the preceding claim or capable of being obtained by the manufacturing process as defined in any one of claims 1 to 6.

9. Battery comprising at least one battery cell as defined in claim 8.

10. Device comprising at least one battery as defined in claim 9.