Active material for electrode of battery cell and method for preparing the same

Abstract

Disclosed are active materials for electrodes of battery cells, wherein the active materials comprise H 2‑x V3O8, wherein x is 0.01 to 0.99. Further disclosed are methods of preparing active materials for electrodes, comprising oxidizing H2V3O8, thereby obtaining H 2‑x V3O8 as active material, wherein x is 0.01 to 0.99, wherein the oxidizing is carried out at a temperature of 80 °C to 150 °C, preferably 100 °C to 130 °C.

Description

TECHNICAL FIELD

[0001] The present invention relates to an active material for an electrode of a battery or battery cell. The invention further relates to an electrode comprising the active material, and to a battery or battery cell comprising such an electrode. The invention further relates to a method of preparing an active material for an electrode of a battery or battery cell. BACKGROUND

[0002] Currently, rechargeable batteries are well known. However, modern rechargeable batteries still have several drawbacks, such as being heavy, having a low capacity, being slow to charge and being fast to age (i.e. properties such as capacity and energy density rapidly decrease after repeated charge / discharge cycles).

[0003] Inorganic materials, in particular ceramics, are often used in batteries and battery cells. One particular example of an inorganic material is H2V3O8, which is often used in a fibrous form, such as nanofibers. H2V3O8 is a compound known since the 1960s and 1970s, of which the structure was partially analyzed in the 1990s, except for the position of the hydrogen atoms (protons). The position of the protons was partially analyzed in 2015.

[0004] H2V3O8 is capable of reversibly exchanging a large number of alkali metal ions and transition metal ions, in particular lithium (Li), sodium (Na), potassium (K), magnesium (Mg) and zinc (Zn). This makes it an interesting compound for use as an active material in metal-ion batteries, such as Li-ion batteries and Mg-ion batteries (MIB).

[0005] H2V3O8 as an active material contributes to an increased capacity of the battery, and it has a high rate capability. For example, in lithium-based batteries, a capacity higher than 400 mAh / g can be achieved. In MIB, an initial discharge capacity of 231 mAh / g at 60 °C, and an average discharge voltage of approximately 1.9 V, resulting in a high energy density of 440 Wh / kg, can be obtained. 2+

[0006] EP 2698854 discloses a method of preparing a particle-based electrode material comprising (partially lithiated) H2V3O8, which is pyrolyzed to obtain an active material.

[0007] US 2017 / 0250449 discloses the use of H2V3O8 and Zn 0.25 V2O5-H2O as an active material for the cathode of a rechargeable zinc-ion battery comprising an aqueous electrolyte. In paragraph

[0081] it is reported that H2V3O8 has a similar capacity to Zn 0.25 ​The lower structural rigidity and flexibility of V2O5-H2O compared to H2V3O8 results in a slightly worse capacity retention after repeated charge / discharge cycles.

[0008] One of the disadvantages of H2V3O8 is the limited chemical stability, which results in poor long-term electrochemical stability (cycling stability) during repeated charge / discharge processes. In other words, it has been noticed that volume changes associated with the reversible exchange of metal in the battery during repeated charge / discharge destroy the H2V3O8 material over time, which results in a significant decrease of the battery cell capacity over time.

[0009] It is now known that the structure of H2V3O8 contains exchangeable protons in an orthorhombic lattice structure. The nature of the protons (hydrogen atoms) can be described as ranging from water-like moieties to mobile protons. Although a certain amount of hydrogen is necessary to keep the orthorhombic structure intact, two hydrogen atoms per chemical formula unit means that one vanadium atom is locked as a 4+ ion, i.e. has an oxidation state of 4+. Compared to vanadium atoms having an oxidation state of 5+, the oxidation state of 4+ means that one equivalent of alkali metal (e.g. lithium) insertion is missing, whereby the capacity of the battery cell is lower.

[0010] Another disadvantage of H2V3O8 is that the exchangeable protons cause corrosion and / or dissolution of the active material, corrosion of the current collector, and poisoning of the electrolyte and anode. The consequence of such damage is a decrease in the capacity of the battery cell.

[0011] EP 2784847 discloses chemically lithiated H2V3O8 - Li x H 2-x V3O8, wherein x is 0.1 to 1.5, preferably close to 1.5. The surface of the chemically lithiated H2V3O8 is treated with Al(OH)3(e.g. by depositing a coating) to improve the cycling stability of a cathode comprising the coated chemically lithiated H2V3O8 as active material. A method for obtaining chemically lithiated H2V3O8 - Li x H 2-x One disadvantage of the method for obtaining chemically lithiated H2V3O8 - Li SUMMARY

[0012] It is an object of the present invention to overcome one or more of the above-mentioned disadvantages. It is an object of the present invention to provide an active material for an electrode of a battery cell, wherein the active material has improved chemical stability, i.e. improved chemical inertness. It is a further object of the present invention to provide an active material which, when used in an electrode of a battery cell, has a higher capacity and a higher long-term electrochemical stability compared to the active materials of the prior art, in particular wherein the capacity is stable over repeated plating / stripping of the cathode and over repeated charge / discharge of the battery cell.

[0013] It is a further object of the present application to provide a method of preparing an active material for an electrode of a battery cell, wherein the method is less complex and / or requires a reduced process duration or time.

[0014] According to a first aspect of the present application, there is provided an active material for an electrode of a battery cell as disclosed in the appended claims.

[0015] The active material comprises H 2-x V3O8, wherein x is 0.01 to 0.99. Advantageously, x is 0.20 to 0.99, such as 0.21 to 0.99, or 0.25 to 0.95.

[0016] According to a second aspect of the present application, there is provided an electrode as disclosed in the appended claims. Advantageously, the electrode is an electrode of a battery cell. The electrode can be a cathode or an anode. The electrode comprises the active material of the first aspect of the present application. Advantageously, the electrode comprises 50 wt.% to 99 wt.%, preferably 75 wt.% to 95 wt.% of the active material, based on the total weight of the electrode.

[0017] Advantageously, the electrode further comprises an electronically conductive material, preferably a carbon-based electronically conductive material. Advantageously, the electrode comprises 0.5 wt.% to 20 wt.%, preferably 2 wt.% to 10 wt.% of the electronically conductive material, preferably a carbon-based electronically conductive material, based on the total weight of the electrode.

[0018] Advantageously, the electrode further comprises a binder. Advantageously, the electrode comprises 0.5 wt.% to 20 wt.%, preferably 1 wt.% to 10 wt.% of the binder, based on the total weight of the electrode.

[0019] The present application further provides a battery cell comprising the electrode of the present application. Advantageously, the battery cell further comprises an electrolyte, preferably a non-aqueous electrolyte. The electrolyte can be a solid electrolyte or a liquid electrolyte.

[0020] According to a third aspect of the present application, there is provided a method of preparing an active material for an electrode as disclosed in the appended claims.

[0021] The method comprises oxidizing H2V3O8, thereby obtaining H 2-x V3O8 as an active material, wherein x is 0.01 to 0.99, such as 0.20 to 0.99, 0.21 to 0.99, or 0.25 to 0.95.

[0022] Advantageously, the oxidizing is performed at a temperature of 80 °C to 150 °C, preferably 100 °C to 130 °C.

[0023] Advantageously, the oxidation of H2V3O8 is performed in the presence of an oxidizing agent. Advantageously, the oxidizing agent is dry air.

[0024] The active material of the present invention has the advantage (but is not limited to) of having a higher chemical stability, manifested as a higher chemical inertness, compared to the active materials of the prior art. When used in an electrode of a battery cell, the active material of the present invention has the advantage of a higher electrochemical stability over time, and a higher capacity that is maintained over repeated charge / discharge of the battery cell. BRIEF DESCRIPTION OF DRAWINGS

[0025] Aspects of the present invention will now be described in more detail, by way of example, with reference to the drawings, in which like reference numerals indicate similar features.

[0026] Figure 1 A configuration of a typical button cell is schematically shown.

[0027] Figure 2 Voltage vs. specific discharge capacity results of a single discharge cycle are shown.

[0028] Figure 3 Discharge capacity curves of battery cells according to Figure 1 , wherein the cathode comprises H2V3O8 (reference battery cell) and H 2-x V3O8 (battery cell of the present invention), respectively, as active material. DETAILED DESCRIPTION

[0030] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0031] The present invention particularly relates to battery cells, such as metal-ion batteries, comprising a metal, in particular an alkali metal or an alkaline earth metal. Preferred examples of alkali metals are lithium (Li) and sodium (Na), the corresponding metal-ion batteries are Li-ion batteries (or LIBs) or Na-ion batteries (or SIBs), respectively. A preferred example of an alkaline earth metal is magnesium (Mg), the corresponding metal-ion battery is a Mg-ion battery (or MIB).

[0032] The present invention also particularly relates to an active material for an electrode of a battery, wherein the active material comprises vanadium (V).

[0033] It is known that for active materials comprising vanadium, when used in electrodes for metal ion batteries, more metal ions (e.g. lithium ions when the battery is a Li-ion battery) can be stored in the active material when the vanadium has an oxidation state of 5+ rather than 4+ or even lower oxidation states. At the battery level, this results in a higher open circuit voltage, which increases the average discharge voltage and thus the energy that the battery can store.

[0034] According to a first aspect of the application, an active material for an electrode of a battery cell comprises H 2-x V3O8, wherein x is 0.01 to 0.99, such as 0.05 to 0.99, 0.10 to 0.99, preferably 0.20 to 0.99, such as 0.21 to 0.99, 0.22 to 0.98, or 0.25 to 0.95.

[0035] It is known in the art that H2V3O8 has an orthorhombic crystal lattice. It is further known in the art that the vanadium atoms of H2V3O8 have an oxidation state of 4+ or 5+, with an average ratio of 1 to 2 of 4+ to 5+. Thus, the average oxidation state of H2V3O8 can be considered to be 4.66+. The present inventors have found that changing the oxidation state of the vanadium atoms in H2V3O8 so as to increase the average oxidation state to a value of 5+, for example by oxidizing H2V3O8 to HV3O8, results in a loss of H 2-x The irreversible structural change caused by the orthorhombic crystal lattice structure of V3O8.

[0036] However, the present inventors have surprisingly found that it is possible to convert H2V3O8 to hydrogen-poor H2V3O8, or H 2-x V3O8, in particular by removing only a fraction of the exchangeable protons from the crystal lattice of H2V3O8. This results in excellent chemical inertness, and thus in excellent chemical stability. The present inventors have in particular found that the method of the present application is able to remove a fraction of these exchangeable protons present in the crystal structure of H2V3O8. Without wishing to be bound by any theory, the present inventors believe that it is necessary to have a very small amount of vanadium atoms with an oxidation state of 4+ in order to maintain the orthorhombic crystal lattice structure of H2V3O8.

[0037] Advantageously, H 2-x V3O8 has an average oxidation state of 4.67+ to 4.99+, i.e. higher than the average oxidation state of H2V3O8, and lower than 5+ due to the presence of some vanadium with an oxidation state of 4+.

[0038] According to a second aspect of the application, there is provided an electrode of a battery cell comprising the active material of the first aspect of the application.

[0039] Advantageously, the electrode comprises 25 to 99.7 weight-%, such as 40 to 99.5 weight-%, preferably 50 to 99 weight-%, for example 60 to 97.5 weight-%, more preferably 75 to 95 weight-% of active material, based on the total weight of the electrode.

[0040] Advantageously, the electrode further comprises an electronically conductive material. Advantageously, the electronically conductive material comprises a carbon-containing material, such as carbon fibers, carbon nanotubes, particulate carbon (e.g. powder), or a combination of two or more thereof. Advantageously, the electronically conductive material is a carbon-based electronically conductive material, such as graphite.

[0041] Advantageously, the electrode comprises 0.1 to 30 weight-%, such as 0.25 to 25 weight-%, preferably 0.5 to 20 weight-%, for example 1 to 15 weight-%, more preferably 2 to 10 weight-% of electronically conductive material, based on the total weight of the electrode.

[0042] Advantageously, the electrode further comprises a binder. The binder can be any binder known in the art, in particular typical binders for active materials comprising vanadium, in particular H2V3O8. Preferred examples of binders are rubbers, such as styrene-butadiene rubber (SBR) or latex, polyvinylidene fluoride (PVDF) and polyvinylpyrrolidone (PVP), in particular high molecular weight PVP.

[0043] Advantageously, the electrode comprises 0.1 to 30 weight-%, such as 0.25 to 25 weight-%, preferably 0.5 to 20 weight-%, for example 0.75 to 15 weight-%, more preferably 1 to 10 weight-% of binder, based on the total weight of the electrode.

[0044] Advantageously, the electrode further comprises a current collector. The current collector can be any current collector known in the art, such as a thin film or foil or sheet material comprising aluminum (Al) and / or titanium (Ti), such as aluminum foil and primed aluminum foil, for example aluminum foil comprising carbon black as primer.

[0045] Advantageously, the active material, the electronically conductive material and the binder are present on the current collector, i.e. deposited on or attached to the current collector.

[0046] The electrode according to the present application can be a cathode or an anode.

[0047] Advantageously, the active material comprised in the electrode comprises 25 to 100 wt% of the active material of the present application, based on the total weight of the active material, such as at least 30%, at least 50%, preferably at least 75%, at least 80%, more preferably at least 90%, such as at least 95% of the active material of the present application. Preferably, the active material of the electrode consists of the active material of the present application. Alternatively, the active material of the electrode can comprise the active material of the present application and one or more other active materials known in the art, such as graphite.

[0048] The present application further provides a battery cell comprising the electrode of the present application. Figure 1 An exemplary embodiment of a battery cell 10 is shown. The battery cell 10 has a coin cell configuration known in the art as a CR2450 type configuration. The battery cell 10 comprises an anode 11 and a cathode 12. The battery cell 10 further comprises an electrolyte 13 between the anode 11 and the cathode 12. Advantageously, the battery cell 10 further comprises a coin cell cover 14, a coin cell base 15, a gasket 16 and a spring 17. The gasket 16 and the spring 17 provide good contact between the other components 11, 12, 13, 14, 15 of the battery cell 10.

[0049] Advantageously, the battery cell is a metal-ion battery cell, wherein the metal is an alkali metal or an alkaline earth metal. Advantageously, the alkali metal is lithium (Li) or sodium (Na). Advantageously, the alkaline earth metal is magnesium (Mg).

[0050] Advantageously, the cathode 12 or the anode 11 is an electrode according to the present application, and the anode 11 or the cathode 12, respectively, is a standard electrode known in the art.

[0051] Advantageously, when the battery cell is a metal-ion battery cell, the electrode according to the present application, i.e. the cathode 12 or the anode 11, is essentially free of metal, and the other electrode, i.e. the anode 11 or the cathode 12, respectively, comprises the metal. The electrode comprising the metal can be a thin film, a foil or a sheet of the metal.

[0052] The electrolyte 13 can be a liquid electrolyte. The liquid electrolyte can comprise a binder. The electrolyte can be an ionic liquid, optionally comprising an organic component, a salt-solvent mixture, preferably a supersaturated salt-solvent mixture. For example, the liquid electrolyte can be an ionic liquid containing a lithium salt dissolved therein, or a mixture of an ionic liquid containing a dissolved lithium salt with an organic liquid. Examples of liquids that can be used include polyethylene glycol dimethyl ether (PEG DME) or an organic solvent such as dioxolane mixed with dimethyl ether. The liquid electrolyte can comprise a compound of tetraethylene glycol dimethyl ether (PEG DME) with lithium bis(trifluorosulfonyl)imide (LiTFSI). Alternatively, the liquid electrolyte can comprise a compound of 1,2-dimethoxyethane with LiTFSI. An ionic liquid that can be used is trifluorosulfonylimide-methyl-butylpyridinium (PYR14TFSI). The electrolyte can also comprise lithium bis(trifluoromethanesulfonyl)imide (LiTFMSI). For example, the electrolyte can be 2.2 M lithium bis(trifluorosulfonyl)imide (LiTFSI) in 1,2-dimethoxyethane.

[0053] Alternatively, the electrolyte 13 can be a solid-state electrolyte. The solid-state electrolyte can be a solid polymer or a solid inorganic material, such as a solid inorganic glass or ceramic material, for example a garnet material. For example, the solid-state electrolyte can be a lithium sulfide solid-state electrolyte, preferably Li3PS4or Li6PS5Br, or can be poly(ethylene oxide) (PEO) with a salt of the battery cell metal, in particular lithium, sodium or magnesium, dispersed in the polymer matrix of the PEO. Alternatively, the solid-state electrolyte can be a garnet ceramic, such as a lithium-filled garnet material, for example lithium lanthanum zirconium oxide (Li7La3Zr20 12 , abbreviated to LLZO).

[0054] Yet alternatively, the electrolyte can be a gel electrolyte. The gel electrolyte can be a polymer-gelled organic medium. For example, the gel electrolyte can be a mixture of poly(methyl methacrylate) (PMMA), a lithium salt and a small amount of liquid.

[0055] Advantageously, the electrolyte 13 is a non-aqueous electrolyte.

[0056] Advantageously, when the electrolyte 13 is a liquid electrolyte or a gel electrolyte, the battery cell 10 comprises a battery separator (not shown) between the anode 11 and the cathode 12. The battery separator can be a porous separator. A polymer battery separator known in the art can be used, such as a porous polypropylene (PP) membrane or a porous polyethylene (PE) membrane. For example, a polypropylene membrane having a thickness of 25 pm and a porosity of 50% can be used. PP and PE are preferred materials because of their chemically inert properties. However, they are not easily wetted, whereas it is preferred that the porous separator can absorb the liquid electrolyte. To this end, the hydrophobic PP and PE can be treated with a surface treatment or coating (such as spray coating, dip coating or plasma coating - atmospheric plasma or low pressure plasma). Alternatively, the battery separator can be a ceramic material.

[0057] According to a third aspect of the present application, a method of preparing an active material for an electrode is provided. Advantageously, the method comprises oxidizing H2V3O8, thereby obtaining H 2-x V3O8 as active material, wherein x is 0.01 to 0.99, such as 0.05 to 0.99, 0.10 to 0.99, preferably 0.20 to 0.99, such as 0.21 to 0.99, 0.22 to 0.98, or 0.25 to 0.95.

[0058] Advantageously, hydrogen atoms are removed from H2V3O8 during the oxidation step. Advantageously, the hydrogen atoms are removed chemically.

[0059] Advantageously, the oxidation is performed at a temperature of 50 °C to 200 °C, such as 75 °C to 225 °C, preferably 80 °C to 150 °C, more preferably 100 °C to 130 °C.

[0060] Advantageously, the oxidation of H2V3O8 is performed in the presence of an oxidizing agent. In particular, the oxidizing agent is in contact with H2V3O8.

[0061] Preferably, the oxidizing agent is a gas or a vapor, i.e. a solid or liquid oxidizing agent that becomes gaseous. Advantageously, the oxidizing agent is dry air. Advantageously, the dry air comprises at most 2000 ppm of water. Another example of an oxidizing agent is pure oxygen (O2), i.e. oxygen having a purity of at least 99%, preferably at least 99.5%, more preferably at least 99.9%. Other examples of oxidizing agents are N2O, and mixtures of O2 and N2, such as mixtures of O2 and N2 of 5 / 95 to 95 / 5.

[0062] Optionally, the method of the present application can be performed in the presence of a catalyst, such as carbon black, carbon nanotubes or graphene.

[0063] The inventors have found that the method of the present invention allows removing only a part of the hydrogen atoms of H2V3O8, thereby preserving the orthorhombic lattice structure of H2V3O8, which provides an active material that reduces vanadium dissolution in the battery cell, providing improved chemical stability (chemical inertness). DETAILED DESCRIPTION

[0064] Example 1

[0065] A mixture comprising V2O5 and V2O3 in a weight ratio of 1 :5 and 6 liters of deionized water is kept under constant stirring in a closed reaction vessel and heated to 200°C for a duration of 30 minutes to 5 hours, preferably 1 to 2 hours. Subsequently, the reaction mixture is cooled to room temperature and the excess water is removed by filtration. Furthermore, any residual water in the reaction mixture is removed by vacuum drying, thereby obtaining H2V3O8.

[0066] Example 2

[0067] A reference cathode comprising H2V3O8 of Example 1 as active material is prepared. A mixture comprising 90 wt% of H2V3O8, 5 wt% of carbon nanotubes (Supplier: Cnano Technology) as electronic conductive material and 5 wt% of high molecular weight polyvinyl pyrrolidone (PVP) (Supplier: Ashland) as binder is prepared. The mixture is dispersed as a 40 wt% slurry in deionized water as solvent. Subsequently, the composition comprising the mixture in deionized water is applied to a 20 micrometer thick aluminum foil as current collector followed by vacuum drying to remove the water, thereby obtaining the reference cathode.

[0068] The cathode according to the present invention is obtained by exposing (contacting) the reference cathode comprising H2V3O8 as active material to a dry air stream at a temperature of 80°C to 150°C, preferably about 120°C for a duration of 1 hour to 48 hours, preferably about 10 hours. H2V3O8 is oxidized by the oxygen in the dry air according to equation (I)

[0069] (I)

[0070] A battery cell according to the present invention is prepared using the cathode of Example 2 (reference battery cell) and the cathode of Example 3 (inventive battery cell), respectively. Figure 1CR2450 coin cell. A 200 micrometer thick lithium metal foil was used as anode. 2.2 M bis(trifluorosulfonyl)imide lithium (LiTFSI, supplied by Nippon Shokubai) in 1,2-dimethoxyethane (Supplier: Merck) was used as liquid electrolyte. Two layers of Teijin MFS FZA1601 (Supplier: Teijin Lielsort Korea) were used as battery separator to separate the cathode from the anode. The battery cell was sealed using a pneumatic press with a pressure of 80 MPa.

[0071] Example 3

[0072] The obtained battery cell according to the application and the reference battery cell were subjected to repeated charge / discharge at 25°C. The specific discharge capacity was measured for each charge / discharge cycle.

[0073] Figure 2 The reference battery cell (21) and the battery cell of the application (20) are shown for the first discharge cycle at a specific current of 0.26 mA / g, the voltage vs. specific discharge capacity relative to Li + / Li corresponding to a discharge duration of 10 hours. The open circuit voltage of the reference battery cell, i.e. the voltage vs. Li + / Li measured at 100% state of charge (100% SOC) was 3.3 V, whereas the battery cell comprising the cathode of the application had an open circuit voltage of 3.5 V relative to Li + / Li was 3.3 V, whereas the battery cell comprising the cathode of the application had an open circuit voltage of 3.5 V relative to Li + / Li was 3.3 V, whereas the battery cell comprising the cathode of the application had an open circuit voltage of 3.5 V relative to Li Figure 2 It can further be seen that for a certain voltage, the battery cell of the application shows a higher specific discharge capacity than the reference battery cell. In other words, for a certain specific discharge capacity, a higher voltage was measured for the battery cell of the application than for the reference battery cell.

[0074] Figure 3 The specific discharge capacity results as a function of the number of charge / discharge cycles (up to 200 cycles) are shown for the battery cell according to the application (30) and the reference battery cell (31). A specific current of 2.6 mA / g (where g stands for the mass of the cathode active material in grams) was applied to the battery cells during a discharge duration of 1 hour. Figure 3 It can be seen that the specific discharge capacity of the battery cell according to the application (30) is higher than the capacity of the reference battery cell (31) at any time. Furthermore, whereas the specific discharge capacity of the reference battery cell starts to decrease after 150 charge / discharge cycles, the specific discharge capacity of the battery cell of the application remains stable up to (at least) 200 cycles.

Claims

1. A method of preparing an active material for an electrode, comprising oxidizing H2V3O8, thereby obtaining as active material HxV3O8, wherein x is 0.01 to 0.99, characterized in that 2- x the step of oxidizing H2V3O8, wherein x is 0.01 to 0.99, is carried out at a temperature of 100 to 300°C. The oxidation is carried out at a temperature of from 80°C to 150°C and uses as oxidizing agent dry air, the oxidation being carried out in the presence of a catalyst chosen from carbon black, carbon nanotubes or graphene.

2. The process of claim 1, wherein the oxidation is carried out at a temperature of from 100°C to 130°C.

3. Active material for an electrode of a battery cell, obtained by the process of claim 1 or 2.

4. The active material of claim 3, wherein x is from 0.20 to 0.

99.

5. The active material of claim 4, wherein x is from 0.21 to 0.

99.

6. The active material of claim 4 or claim 5, wherein x is from 0.25 to 0.

95.

7. An electrode comprising the active material of any one of claims 3 to 6.

8. The electrode of claim 7, comprising from 50% to 99% by weight of the active material, based on the total weight of the electrode.

9. The electrode of claim 7, comprising from 75% to 95% by weight of the active material, based on the total weight of the electrode.

10. The electrode of claim 7, further comprising a carbon-based electronically conductive material.

11. The electrode of claim 10, comprising from 0.5% to 20% by weight of the carbon-based electronically conductive material, based on the total weight of the electrode.

12. The electrode of claim 10, comprising from 2% to 10% by weight of the carbon-based electronically conductive material, based on the total weight of the electrode.

13. The electrode of claim 7 or 10, further comprising a binder.

14. The electrode of claim 13, comprising from 0.5% to 20% by weight of the binder, based on the total weight of the electrode.

15. The electrode of claim 13, comprising from 1% to 10% by weight of the binder, based on the total weight of the electrode.

16. A battery cell comprising the electrode of any one of claims 7 to 15.

17. The battery cell of claim 16, further comprising a non-aqueous electrolyte.

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