Layered oxide positive electrode material and preparation method and application thereof

Abstract

The invention belongs to the technical field of secondary batteries, and particularly relates to a layered oxide positive electrode material and a preparation method and application thereof. The preparation method of the layered oxide positive electrode material comprises the following steps: S1, mixing a nickel-iron-manganese precursor, a sodium source and zirconium dioxide, sintering for the first time, and crushing to obtain a first sintered material; s2, mixing the first sintered material and a phosphorus source, and sintering for the second time to obtain a second sintered material; the preparation method is simple, industrial production is convenient, and the obtained layered oxide positive electrode material is high in specific capacity, low in residual alkali and excellent in cycle performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of secondary batteries, and particularly relates to a layered oxide cathode material, a preparation method thereof, and an application thereof. Background Art

[0002] Lithium-ion batteries are the most widely used secondary batteries in the current market, and their application fields can cover electric bicycles, electric vehicles, mobile devices, etc. However, restricted by the objective condition of uneven global lithium resource distribution, its development prospect and future cost are subject to certain restrictions. Sodium-ion batteries have a working principle similar to that of lithium-ion batteries. Analogous to the reversible insertion and extraction of lithium ions between the positive and negative electrodes in lithium-ion batteries to achieve energy storage and release, in sodium-ion batteries, sodium ions are reversibly inserted and extracted between the positive and negative electrodes. However, different from lithium-ion batteries whose cost will be restricted, sodium-ion batteries have a wide range of application prospects due to their wide range of raw material sources and certain cost advantages.

[0003] In existing sodium-ion batteries, the cathode material is an important factor affecting the overall performance of the battery. The cathode materials for sodium-ion batteries mainly include three categories: transition metal oxide systems, polyanion compounds (phosphate systems, fluorophosphate systems, NASICON structures), and Prussian blue systems. Among them, P2-type transition metal oxide cathode materials have a high voltage platform and excellent rate performance, but the P2-type transition metal oxide cathode materials have a relatively low specific capacity and the residual alkali is prone to be on the high side, which limits their application in high energy density scenarios. Summary of the Invention

[0004] Therefore, the present invention provides a layered oxide cathode material, a preparation method thereof, and an application thereof. The layered oxide cathode material has a relatively stable structure, a high specific capacity, a low residual alkali content, and thus has better cycle stability.

[0005] For this reason, the present invention provides the following technical solutions.

[0006] The present invention provides a preparation method for a layered oxide cathode material, comprising the following steps: S1: Mix a nickel-iron-manganese precursor, a sodium source, and zirconium dioxide, perform a first sintering, and pulverize to obtain a first sintered material; S2: Mix the first sintered material and a phosphorus source, and perform a second sintering to obtain a second sintered material.

[0007] In the preparation method for the layered oxide cathode material provided by the present invention, when the phosphorus source is added in the form of an aqueous solution, typically but not limitedly, it is possible to spray the phosphorus source aqueous solution onto the first sintered material while stirring the first sintered material to make the phosphorus source and the first sintered material mix more uniformly.

[0008] Optionally, in S1, the mass ratio of zirconia to the nickel-iron-manganese precursor is 3-15:1000; optionally, the mass ratio of zirconia to the nickel-iron-manganese precursor is 8-12:1000.

[0009] Optionally, in S2, the mass ratio of the phosphorus source to the first-fired material is 1.0-2.0:100; optionally, the mass ratio of the phosphorus source to the first-fired material is 1.3-1.4:100.

[0010] Optionally, in S1, the first sintering is carried out in an oxygen-containing atmosphere at a temperature of 900-1100 °C for a time of 10-15 h; optionally, the temperature is 1000-1100 °C and the time is 11-13 h.

[0011] Optionally, in S2, the second sintering is carried out in an oxygen-containing atmosphere at a temperature of 700-900 °C for a time of 4-10 h; optionally, the temperature is 750-850 °C and the time is 5-7 h.

[0012] Typically and non-limitingly, the oxygen-containing atmosphere during sintering can be maintained by introducing air into the furnace, and the air introduction rate is 5 m 3 / h.

[0013] Optionally, in S1, the molar ratio of sodium element in the sodium source to the metal elements in the nickel-iron-manganese precursor is 0.65-0.71:1.

[0014] Optionally, the nickel-iron-manganese precursor is Ni x Fe y Mn z (OH)2, where x + y + z = 1, 0.2 ≤ x ≤ 0.3, 0.2 ≤ y ≤ 0.3, 0.5 ≤ z ≤ 0.6.

[0015] Optionally, the sodium source includes at least one of sodium carbonate, sodium bicarbonate, and sodium hydroxide.

[0016] Optionally, the phosphorus source includes at least one of phosphoric acid, sodium hydrogen phosphate, and sodium dihydrogen phosphate; optionally, the phosphorus source is phosphoric acid.

[0017] Optionally, the phosphorus source is added in the form of an aqueous solution, and the mass percentage of the phosphorus source aqueous solution is 15%-20%; optionally, the mass percentage of the phosphorus source aqueous solution is 16%-17%.

[0018] The present invention provides a layered oxide cathode material prepared by the above preparation method.

[0019] The present invention also provides an application of the above layered oxide cathode material in a secondary battery; optionally, the secondary battery includes a sodium ion battery. Typically and non-limitingly, an assembly method of a sodium ion button half-cell can be as follows: the obtained cathode material is mixed uniformly with a conductive agent acetylene black and a binder PVDF according to a mass ratio of 80-95:2-12:2-8, an appropriate amount of 1-methyl-2-pyrrolidone is added and ball milled for 1-3 h to obtain a slurry, which is coated on an aluminum sheet, dried and pressed into a cathode sheet, a sodium metal sheet is used as the anode, sodium hexafluorophosphate (NaPF6) is used as the electrolyte, and a mixture of dimethyl carbonate and ethylene carbonate with a volume ratio of 1:1 is used as the solvent to assemble a 2032 button battery.

[0020] The beneficial effects of the present invention are as follows:

[0021] The preparation method of the layered oxide cathode material provided by the present invention includes the following steps: S1: mixing a nickel-iron-manganese precursor, a sodium source, and zirconium dioxide, sintering for the first time, and pulverizing to obtain a first-sintered material; S2: mixing the first-sintered material and a phosphorus source, and sintering for the second time to obtain a second-sintered material. This preparation method is simple and convenient for industrial production, and the obtained layered oxide cathode material has a high specific capacity, low residual alkali, and excellent cycle performance. Among them, the cathode material formed by the nickel-iron-manganese precursor has a relatively high capacity. When sintering the nickel-iron-manganese precursor and the sodium source for the first time, zirconium dioxide is incorporated for co-sintering, and zirconium atoms will dope and occupy positions in the transition metal layer, which can inhibit the Jahn-Teller effect of the Fe-O octahedron and the migration of Fe 4+ Thereby reducing the internal stress pulling of the cathode material during the charge and discharge cycle. Mixing the first-sintered material with the phosphorus source for the second sintering can, on the one hand, dope phosphorus atoms on the surface layer of the layered oxide cathode material to form P-O bonds, increasing the structural toughness of the surface layer of the layered oxide cathode material and enhancing its cycle stability; on the other hand, the phosphorus source can react with the residual alkali on the surface of the first-sintered material to obtain a sodium phosphate electrolyte, which can not only reduce the residual alkali, but also form a stable coating layer on the surface of the layered oxide cathode material, further improving the cycle stability of the layered oxide cathode material. Description of the Drawings

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is the SEM image of the layered oxide cathode material obtained in Example 1 of the present invention, with a magnification of 3000 times. Detailed Embodiments

[0024] The following embodiments are provided to better understand the present invention further. It is not limited to the described optimal implementation mode, and does not constitute a limitation on the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with those of other existing technologies falls within the protection scope of the present invention.

[0025] For those not specifying specific experimental steps or conditions in the embodiments, operations or conditions of conventional experimental steps described in the literature in this field can be followed. For reagents or instruments not indicating the manufacturer, they are all conventional reagent products that can be obtained through commercial purchase.

[0026] Example 1

[0027] This example provides a layered oxide cathode material and its preparation method, including the following steps:

[0028] (1) Take 5.0 kg of Ni 0.30 Fe 0.20 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 45 g of zirconium dioxide, mix them in a high-speed mixer, feed them into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, sinter at 1000 °C for 12 h, and pulverize to obtain a first-fired material.

[0029] (2) Take 8.2 g of 85 wt% H3PO3 in a beaker, add 33 g of pure water for dilution to obtain dilute phosphoric acid of about 16.9 wt%.

[0030] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all spraying, feed it into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, sinter at 800 °C for 6 h to obtain a layered oxide cathode material.

[0031] Example 2

[0032] This example provides a layered oxide cathode material and its preparation method, including the following steps:

[0033] (1) Take 5.0 kg of Ni 0.30 Fe 0.20 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 40 g of zirconium dioxide, mix them in a high-speed mixer, feed them into a box furnace, and introduce air into the furnace at a rate of 5 m 3Air is introduced at a rate of / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 1000 °C for 13 h, followed by pulverization to obtain a first-fired material.

[0034] (2) Take 7.65 g of 85 wt% H3PO3 in a beaker, add 33 g of pure water for dilution to obtain dilute phosphoric acid of about 16 wt%.

[0035] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all the spraying, it is sent into a box furnace, and air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 750 °C for 7 h to obtain a layered oxide cathode material.

[0036] Example 3

[0037] This example provides a layered oxide cathode material and its preparation method, including the following steps:

[0038] (1) Take 5.0 kg of Ni 0.30 Fe 0.20 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 60 g of zirconia, mix them in a high-speed mixer, send them into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 1100 °C for 11 h, followed by pulverization to obtain a first-fired material.

[0039] (2) Take 8.24 g of 85 wt% H3PO3 in a beaker, add 33 g of pure water for dilution to obtain dilute phosphoric acid of about 17 wt%.

[0040] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all the spraying, it is sent into a box furnace, and air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 850 °C for 5 h to obtain a layered oxide cathode material.

[0041] Example 4

[0042] This example provides a layered oxide cathode material and its preparation method, including the following steps:

[0043] (1) Take 5.0 kg of Ni 0.20 Fe 0.20 Mn 0.60 (OH)2 precursor, 2.0 kg of sodium carbonate, and 15 g of zirconia, mix them in a high-speed mixer, send them into a box furnace, and introduce air into the furnace at a rate of 5 m 3Air is introduced at a rate of 5 m / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 900 °C for 15 h, followed by pulverization to obtain a first-fired material.

[0044] (2) Take 5.88 g of 85 wt% H3PO3 in a beaker, add 27.5 g of pure water for dilution to obtain dilute phosphoric acid of about 15 wt%.

[0045] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all the spraying, it is sent into a box furnace, and air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 700 °C for 10 h to obtain a layered oxide cathode material.

[0046] Example 5

[0047] This example provides a layered oxide cathode material and its preparation method, including the following steps:

[0048] (1) Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 75 g of zirconia, mix them in a high-speed mixer, send them into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 1100 °C for 10 h, followed by pulverization to obtain a first-fired material.

[0049] (2) Take 11.76 g of 85 wt% H3PO3 in a beaker, add 38.2 g of pure water for dilution to obtain dilute phosphoric acid of about 20 wt%.

[0050] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all the spraying, it is sent into a box furnace, and air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 900 °C for 4 h to obtain a layered oxide cathode material.

[0051] Comparative Example 1

[0052] This comparative example provides a layered oxide cathode material and its preparation method, including the following steps:

[0053] Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, mix them in a high-speed mixer, send them into a box furnace, and introduce air into the furnace at a rate of 5 m 3Air is introduced at a rate of / h to maintain an oxygen-containing atmosphere, and sintering is carried out at 1100 °C for 10 h, followed by pulverization to obtain a layered oxide cathode material.

[0054] Comparative Example 2

[0055] This comparative example provides a layered oxide cathode material and a preparation method thereof, including the following steps:

[0056] Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 75 g of zirconium dioxide, mix them in a high-speed mixer, feed them into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, sinter at 1100 °C for 10 h, and pulverize to obtain a layered oxide cathode material.

[0057] Comparative Example 3

[0058] This comparative example provides a layered oxide cathode material and a preparation method thereof, including the following steps:

[0059] (1) Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, mix them in a high-speed mixer, feed them into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, sinter at 1100 °C for 10 h, and pulverize to obtain a first-fired material.

[0060] (2) Take 11.76 g of 85 wt% H3PO3 in a beaker, add 38.2 g of pure water for dilution to obtain approximately 20 wt% dilute phosphoric acid.

[0061] (3) Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and simultaneously spray the dilute phosphoric acid obtained in (2) into it. After all spraying, feed it into a box furnace, and introduce air into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, sinter at 900 °C for 4 h to obtain a layered oxide cathode material.

[0062] Comparative Example 4

[0063] This comparative example provides a layered oxide cathode material and a preparation method thereof, including the following steps:

[0064] (1) Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50(OH)2 precursor, 2.0 kg of sodium carbonate, and 75 g of alumina are mixed in a high-speed mixer and fed into a box furnace. Air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintered at 1100 °C for 10 h, then pulverized to obtain a first-fired material.

[0065] Take 11.76 g of 85 wt% H3PO3 in a beaker, add 38.2 g of pure water for dilution to obtain dilute phosphoric acid of about 20 wt%.

[0066] Take 500 g of the first-fired material obtained in (1), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (2) into it. After all the spraying, it is fed into a box furnace. Air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintered at 900 °C for 4 h to obtain a layered oxide cathode material.

[0067] Comparative Example 5

[0068] This comparative example provides a layered oxide cathode material and its preparation method, including the following steps:

[0069] Take 5.0 kg of Ni 0.20 Fe 0.30 Mn 0.50 (OH)2 precursor, 2.0 kg of sodium carbonate, and 75 g of zirconia are mixed in a high-speed mixer and fed into a box furnace. Air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintered at 1100 °C for 10 h, then pulverized to obtain a first-fired material.

[0070] Take 500 g of the first-fired material obtained in (1) and 10 g of carbon nanotubes, mix them in a high-speed mixer, feed them into a box furnace, maintain a nitrogen atmosphere in the furnace, sinter at 810 °C for 10 h, and pulverize to obtain a second-fired material.

[0071] Take 11.76 g of 85 wt% H3PO3 in a beaker, add 38.2 g of pure water for dilution to obtain dilute phosphoric acid of about 20 wt%.

[0072] Take 500 g of the second-fired material obtained in (2), put it into a high-speed mixer for stirring, and at the same time spray the dilute phosphoric acid obtained in (3) into it. After all the spraying, it is fed into a box furnace. Air is introduced into the furnace at a rate of 5 m 3 / h to maintain an oxygen-containing atmosphere, and sintered at 900 °C for 4 h to obtain a layered oxide cathode material.

[0073] Test Example 1

[0074] Observe the SEM image of the layered oxide cathode material prepared in Example 1, as shown in Figure 1 , it can be seen that the surface of the particles is clean without any attachments or traces of residual alkali erosion.

[0075] Test Example 2

[0076] Take the layered oxide cathode materials obtained in the examples and test examples, and use acid-base neutralization titration to test the surface residual alkali content. The test data are shown in Table 1.

[0077] Test Example 3

[0078] Take the layered oxide cathode materials obtained in the examples and test examples. Mix the layered oxide cathode materials with conductive agent acetylene black and binder PVDF evenly according to the mass ratio of 80:12:8, add an appropriate amount of 1-methyl-2-pyrrolidone and ball mill for 2 h to obtain a slurry. Coat the slurry on an aluminum sheet, dry and press it into a positive electrode sheet. Use a sodium metal sheet as the negative electrode, sodium hexafluorophosphate (NaPF6) as the electrolyte, and a mixture of dimethyl carbonate and ethylene carbonate with a volume ratio of 1:1 as the solvent to assemble a 2032 coin cell, and use a Siken test system to conduct electrical performance tests. In the range of charge-discharge cut-off voltages of 2.5 - 4.2 V, test the first charge-discharge specific capacity at 0.1C, and the charge-discharge ratio is the first efficiency. At 25°C, test the 50-cycle capacity retention rate at 1C / 1C charge-discharge. All the obtained data are shown in Table 1.

[0079] Table 1

[0080]

[0081] Compared with Example 5, in Comparative Example 1 of the present invention, neither zirconium is doped nor phosphorus is added externally; in Comparative Example 2, only zirconium is doped and there is no step of phosphorus coating; in Comparative Example 3, zirconium is not doped and only the step of phosphorus coating is retained; in Comparative Example 4, zirconium oxide is replaced with aluminum oxide; in Comparative Example 5, zirconium is doped and phosphorus is coated, but after the first firing of the zirconium-doped material, an additional step of carbon coating is added and then phosphorus is coated.

[0082] It can be seen from Table 1 that compared with the examples, the layered oxide cathode materials obtained in the comparative examples that do not conform to the preparation method in the present application have high residual alkali, low specific capacity, low first efficiency, and low cycle retention rate. In Comparative Examples 1 and 2, due to the absence of phosphorus source coating, the residual alkali content is relatively high, and the first efficiency, specific capacity, and cycle retention rate are all very poor. Although phosphorus source coating is used in Comparative Examples 3 and 4, there is no zirconium doping or other metals are used for doping, and the residual alkali content cannot be reduced to the same level as that of the examples, and the first efficiency, specific capacity, and cycle retention rate are all relatively poor. Although the residual alkali and electrical properties of Comparative Example 5 are close to those of the examples, an additional layer of carbon is coated, the preparation method is complex, and there is no improvement in the electrical properties of the materials obtained compared with the preparation method of the present invention.

[0083] It can also be seen from the examples that, compared with Examples 4 and 5, the layered oxide cathode materials obtained in Examples 1 to 3 with sintering parameters and raw material ratios within the preferred ranges have lower residual alkalis and more excellent electrical properties. The first charge specific capacity at 0.1C is above 132 mAh / g, the first discharge specific capacity at 0.1C is above 120 mAh / g, the retention rate after 50 cycles is not less than 96.5%, and the residual NaOH is lower than 0.1 wt%.

[0084] Obviously, the above examples are only for clear illustration and not a limitation on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A method for preparing a layered oxide positive electrode material, characterized in that: The steps include: S1: mixing nickel iron manganese precursor, sodium source and zirconium dioxide, sintering for the first time, and crushing to obtain a sintered material; S2: Mix the first sintered material and the phosphorus source, and sinter for the second time to obtain the second sintered material.

2. The preparation method according to claim 1, characterized in that: In S1, the mass ratio of zirconium dioxide to nickel-iron-manganese precursor is 3 to 15:1000; optionally, the mass ratio of zirconium dioxide to nickel-iron-manganese precursor is 8 to 12:1000.

3. The preparation method according to claim 1 or 2, characterized in that: In S2, the mass ratio of the phosphorus source to the first fumed material is 1.0-2.0:100; optionally, the mass ratio of the phosphorus source to the first fumed material is 1.3-1.4:

100.

4. The preparation method according to any one of claims 1 to 3, characterized in that: In S1, the first sintering is carried out in an oxygen-containing atmosphere at a temperature of 900-1100° C. for 10-15 hours; optionally, the temperature is 1000-1100° C. for 11-13 hours; And / or, in S2, the second sintering is carried out in an oxygen-containing atmosphere at a temperature of 700-900° C. for 4-10 hours; optionally, the temperature is 750-850° C. for 5-7 hours.

5. The preparation method according to any one of claims 1 to 4, characterized in that: In S1, the molar ratio of the sodium element in the sodium source to the metal element in the nickel-iron-manganese precursor is 0.65-0.71:

1.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The Ni-Fe-Mn precursor x Fe y Mn z (OH)2, wherein x+y+z=1, 0.2≤x≤0.3, 0.2≤y≤0.3, 0.5≤z≤0.

6.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The sodium source includes at least one of sodium carbonate, sodium bicarbonate and sodium hydroxide; And / or, the phosphorus source includes at least one of phosphoric acid, sodium hydrogen phosphate and sodium dihydrogen phosphate; optionally, the phosphorus source is phosphoric acid.

8. The preparation method according to any one of claims 1 to 7, characterized in that: The phosphorus source is added in the form of an aqueous solution, and the mass percentage of the phosphorus source aqueous solution is 15% to 20%; optionally, the mass percentage of the phosphorus source aqueous solution is 16% to 17%.

9. A layered oxide positive electrode material obtained by the preparation method according to any one of claims 1 to 8.

10. Use of the layered oxide positive electrode material as claimed in claim 9 in a secondary battery; optionally, the secondary battery comprises a sodium ion battery.

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