WO2020124507A1

WO2020124507A1 - Crystalline material, preparation method therefor and application thereof, positive electrode active material of battery, positive electrode material of battery, battery and electrical equipment

Info

Publication number: WO2020124507A1
Application number: PCT/CN2018/122436
Authority: WO
Inventors: 唐永炳; 何海燕; 姚文娇
Original assignee: 深圳先进技术研究院
Priority date: 2018-12-20
Filing date: 2018-12-20
Publication date: 2020-06-25

Abstract

The present application relates to the technical field of positive electrode active materials of batteries, and provided thereby are a crystalline material, a preparation method therefor and an application thereof, a positive electrode active material of a battery, a positive electrode material of a battery, a battery and an electrical equipment. The crystalline material has a molecular formula of KLi₃Tm(C₂O₄)₃, wherein Tm is a transition metal, and the transition metal is at least one selected from among Co, Ni, Mn, Cu, Zn, Ti, V and Cr. Therefore, the technical problems in which the types of existing positive electrode active materials of potassium ion batteries are limited, and the electrochemical performance of potassium ion batteries made using said types is not ideal are ameliorated. The crystalline material provided by the present application simultaneously has potassium ions and lithium ions, and may be applied both to potassium ion batteries as a positive electrode active material and lithium ion batteries as a positive electrode active material, which effectively expands the types of positive electrode active materials of batteries and increases battery capacity.

Description

Crystal material, preparation method and application, battery positive active material, battery positive material, battery and electrical equipment

Technical field

The present application relates to the technical field of battery positive active materials, in particular to a crystalline material and its preparation method and application, battery positive active material, battery positive material and battery and electrical equipment.

Background technique

The secondary battery is also called a rechargeable battery, and is a battery that can be repeatedly charged and discharged and used many times. At present, the main secondary battery technologies are lead-acid batteries, nickel-chromium batteries, nickel-metal hydride batteries and lithium-ion batteries, among which lithium-ion batteries are the most widely used. Lithium-ion batteries have the advantages of high energy density, high energy efficiency, long cycle life, no memory effect, and rapid charge and discharge. Therefore, they are huge in consumer electronics and electric vehicles, power grid peaking, energy storage power supplies, and aerospace. Market demand.

Although lithium-ion batteries have many advantages and a wide range of applications, lithium resources have limited reserves in the earth's crust. As an energy storage technology that potentially replaces lithium-ion batteries, potassium-ion batteries have received increasing attention in recent years. A common potassium ion battery uses Prussian blue and its analogues, iron phosphate or fluorosulfate as positive active materials, and carbon materials as negative active materials. However, the types of cathode materials currently developed based on potassium ion batteries are very limited, and the electrochemical performance of potassium ion batteries made of developed cathode active materials is not very satisfactory.

In view of this, this application is hereby submitted.

Summary of the invention

One of the purposes of the present application is to provide a crystalline material to improve the existing positive electrode active materials of potassium ion batteries with limited types, and the electrochemical performance of the potassium ion batteries manufactured by using them is not ideal.

The crystalline material provided in this application has a molecular formula of KLi ₃ Tm(C ₂ O ₄ ) ₃ , and the Tm is a transition metal selected from Co, Ni, Mn, Cu, Zn, Ti, V and At least one of Cr;

Further, the KLi ₃ Tm(C ₂ O ₄ ) ₃ is a trigonal crystal, the space group is R-3c, and Tm is respectively connected to six oxygens derived from oxalate to form an octahedron.

The second objective of the present application is to provide a method for preparing a crystalline material, which includes the following steps: a solvothermal reaction is performed on a potassium source, a lithium source, a transition metal source, and an oxalic acid source to obtain KLi ₃ Tm(C ₂ O ₄ ) ₃ ;

Wherein, Tm is a transition metal, and the transition metal source is selected from at least one of a cobalt source, a nickel source, a manganese source, a copper source, a zinc source, a titanium source, a vanadium source, and a chromium source.

Further, the molar ratio of the potassium source, lithium source, transition metal source and oxalic acid source is (1-20): (1-40): (1-2): (2-20), preferably (1- 2): (1-4): (1-2): (2-5);

Preferably, the solvent for the solvothermal reaction is selected from at least one of water, alcohols, ketones or pyridine solvents, preferably water;

Preferably, the molar ratio of potassium source, lithium source, transition metal source, oxalic acid source and water is (1-20): (1-40): (1-2): (2-20): (10-500) , Preferably (1-2): (1-4): (1-2): (2-5): (10-20).

Further, the potassium source is selected from at least one of potassium element, potassium oxide or potassium salt, preferably potassium salt;

And/or, the lithium source is selected from at least one of lithium element, lithium oxide, or lithium salt, preferably a lithium salt;

And/or, the source of the transition metal is at least one selected from the group consisting of a transition metal element, a transition metal oxide, or a transition metal salt; preferably a metal salt;

And/or, the oxalic acid source is selected from oxalic acid and/or oxalate, preferably oxalic acid.

The third objective of the present application is to provide the application of the crystalline material provided by the present application or the crystalline material obtained by the preparation method provided by the present application in a battery positive active material.

The fourth purpose of this application is to provide a positive electrode active material for a battery, including the crystalline material described in this application or the crystalline material obtained by the preparation method described in this application;

Preferably, the battery cathode material includes a crystalline material, a cathode conductive agent, and a cathode binder;

Preferably, the battery cathode material includes crystalline material 60-90wt%, cathode conductive agent 5-30wt% and cathode binder 5-10wt%;

Preferably, the battery cathode material includes a lithium-deficient cathode active material, KLi ₃ Tm(C ₂ O ₄ ) ₃ , a cathode conductive agent, and a cathode binder;

Preferably, the battery cathode material includes lithium-deficient cathode active material 40-60wt%, KLi ₃ Co(C ₂ O ₄ ) ₃ 10-30wt%, cathode conductive agent 5-30wt% and cathode binder 5-10wt% ;

Preferably, the lithium-deficient positive active material is selected from CoSO ₄ F and/or CoPO ₄ .

The fifth object of the present application is to provide a battery including the crystalline material provided by the present application, the crystalline material obtained by the preparation method described in the present application, the battery active material described in the present application or the battery positive active material or the present application described in the present application The battery cathode material as described in the application;

Preferably, the battery is a potassium ion battery or a lithium ion battery.

The sixth object of the present application is to provide an electric device including the crystalline material provided by the present application, the crystalline material obtained by the preparation method described in the present application, the battery active material described in the present application, and the battery positive electrode active material in the present application 3. The battery positive electrode material described in this application or the battery described in this application.

The crystalline material provided by this application has both potassium ions and lithium ions, which can be applied to both potassium ion batteries as positive electrode active materials and lithium ion batteries as positive electrode active materials, effectively expanding the types of battery positive electrode active materials and improving battery capacity.

The preparation method of the crystalline material provided by the present application is simple in process, low in raw materials, suitable for large-scale production, and can effectively reduce the preparation cost of the positive electrode active material of the battery.

BRIEF DESCRIPTION

FIG. 1a is a schematic structural diagram of KLi ₃ Co(C ₂ O ₄ ) ₃ provided by this application;

FIG. 1b is a schematic structural view of KLi ₃ Co(C ₂ O ₄ ) ₃ shown in FIG. 1 from another angle;

2 is an XRD comparison chart of the KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles prepared in Example 1 of the present application and the standard KLi ₃ Co(C ₂ O ₄ ) ₃ crystal;

3 is an XRD comparison chart of the KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles prepared in Example 6 of the present application and the standard KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal;

4 is a thermogravimetric and differential scanning calorimetry curve diagram of KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles prepared in Example 1 of the present application;

5 is a graph of thermogravimetric and differential scanning calorimetry curves of KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles prepared in Example 6 of the present application;

6 is a constant current charge-discharge curve diagram of the potassium ion half-cell provided in Example 13;

7 is a constant current charge-discharge curve diagram of the lithium ion half-cell provided in Example 24. FIG.

detailed description

The embodiments of the present application will be described in detail below in conjunction with examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If no specific conditions are indicated in the examples, the conventional conditions or the conditions recommended by the manufacturer shall be used. The reagents or instruments used do not indicate the manufacturer, are all conventional products that can be obtained through commercial purchase.

It should be noted:

In this application, unless otherwise specified, all the embodiments and preferred implementation methods mentioned herein can be combined with each other to form a new technical solution.

In this application, unless otherwise specified, the percentage (%) or part refers to the weight percentage or part by weight relative to the composition.

In this application, unless otherwise specified, the involved components or their preferred components can be combined with each other to form a new technical solution.

In this application, unless otherwise stated, the numerical range "a-b" represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "6-22" means that all real numbers between "6-22" have been listed in this article, and "6-22" is just an abbreviated representation of these numerical combinations.

The forms of the "lower limit" and the upper limit disclosed in the "range" of this application may be one or more lower limits and one or more upper limits, respectively.

In this application, unless otherwise stated, each reaction or operation step may be performed sequentially or in order. Preferably, the reaction methods herein are performed sequentially.

Unless otherwise stated, the technical and scientific terms used in this article have the same meaning as those familiar to those skilled in the art. In addition, any method or material similar to or equivalent to the described content can also be applied to this application.

According to an aspect of the present application, the present application provides a crystalline material having a molecular formula of KLi ₃ Tm(C ₂ O ₄ ) ₃ , the Tm is a transition metal, and the transition metal is selected from Co, Ni, Mn , Cu, Zn, Ti, V and Cr at least one.

In a preferred embodiment of the present application, KLi ₃ Tm(C ₂ O ₄ ) ₃ is a trigonal crystal, the space group is R-3c, and Tm is respectively connected with six oxygens derived from oxalate to form an octahedron.

Taking Tm as Co as an example, FIG. 1a is a schematic structural diagram of KLi ₃ Tm(C ₂ O ₄ ) ₃ , and FIG. 1b is a schematic structural diagram of KLi ₃ Co(C ₂ O ₄ ) ₃ shown in FIG. 1 from another angle.

As can be seen from Figures 1a and 1b, KLi ₃ T _m (C ₂ O ₄ ) ₃ is a trigonal crystal system, and Co is connected to six oxygens from oxalate to form an irregular octahedron, which makes the crystal material more Abundant pores provide migration of lithium ions and potassium ions, and improve the performance and structural stability of lithium or potassium intercalation and desorption of crystalline materials.

According to the second aspect of the present application, the present application provides a method for preparing a crystalline material, including the following steps:

The potassium source, lithium source, transition metal source and oxalic acid source undergo a solvothermal reaction to obtain KLi ₃ Tm(C ₂ O ₄ ) ₃ , where Tm is a transition metal;

Wherein, the transition metal source is selected from one or more of cobalt source, nickel source, manganese source, copper source, zinc source, titanium source and vanadium source.

The preparation method of the crystalline material provided by the present application is obtained by a low-cost potassium source, lithium source, transition metal source and oxalic acid source through a solvothermal reaction. The process is simple and the operation is convenient, which can effectively reduce the cost of the battery positive electrode active material and has a broad Application prospects.

In a preferred embodiment of the present application, the temperature of the solvothermal reaction is 150-300°C. The temperature of the solvothermal reaction promotes the formation of crystalline materials and improves the preparation efficiency, especially when the reaction temperature is 180-220°C, which is more conducive to the generation of crystalline materials and the improvement of the preparation efficiency.

Typical but non-limiting, the temperature of the solvothermal reaction is, for example, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240 or 250°C.

In a preferred embodiment of the present application, the solvothermal reaction time is 4-96h. By controlling the time of the solvothermal reaction, the above raw materials are reacted more fully to improve the yield of crystalline materials. Especially when the solvothermal reaction time is 48h, it can not only ensure a higher yield of crystalline materials, but also avoid the waste of energy.

In a preferred embodiment of the present application, the molar ratio of the potassium source, lithium source, transition metal source and oxalic acid source is (1-20): (1-40): (1-2): (2-20) In order to improve the yield of crystalline materials, thereby effectively improving the utilization rate of raw materials and reducing the waste of raw materials.

In a further preferred embodiment of the present application, when the molar ratio of the potassium source, lithium source, transition metal source and oxalic acid source is preferably (1-2): (1-4): (1-2): (2- 5), the yield of crystalline materials is higher, which can reach more than 60%.

Typical but non-limiting, the moles of potassium source, lithium source, transition metal source and oxalic acid source are 1:2:1:3, 1:2:1:4, 1:2:1:5, 1.5:2 :1.2:4, 1.2:2.2:1.5:4 or 1.5:2.2:1.2:4.

In a preferred embodiment of the present application, the solvent for solvothermal reaction is one or more selected from the group consisting of water, alcohols, ketones or pyridines. When water is used as the solvent, the operation is safer and more environmentally friendly.

In a preferred embodiment of the present application, the molar ratio of potassium source, lithium source, transition metal source, oxalic acid source and water is (1-2): (1-4): (1-2): (2- 5): (10-500).

In a preferred embodiment of the present application, water is used as a solvent to provide a mixing medium for the above raw materials. By controlling the molar ratio of the raw materials to the above raw materials, sufficient reaction can be ensured between the raw materials, thereby effectively increasing the yield of crystalline materials.

Typical but non-limiting, the moles of lithium source and water are 1:10, 1:20, 1:30, 1:40, 1:50, 1.5:10, 1.5:20, 1.5:30, 1.5:40 , 1.5:50, 1:5, 1:15, or 1:25.

In a preferred embodiment of the present application, the potassium source is selected from one or more of potassium simple substance, potassium oxide or potassium salt, especially when the potassium source is potassium salt, it is easier to prepare crystals.

In a preferred embodiment of the present application, the potassium salt is selected from KI, KCl, KF, K ₂ SO ₄ , KNO ₃ , KBr, KNO ₃ , KSCN, KOCN, K ₂ WO ₄ , K ₂ IrCl ₆ , K ₂ MoO ₄ , K2CrO ₄ , K ₄ FeC ₆ N ₆ , K ₃ FeC ₆ N ₆ , K ₃ PO ₄ , K ₂ S ₂ O ₇ , K ₂ S ₂ O ₅ , KH ₃ C ₄ O ₈ , K ₂ Cr ₂ O ₇ , KHF ₂ , K ₂ PtCl ₆ , K ₂ SnO ₃ , K ₄ P ₂ O ₇ , K ₂ HPO ₄ , KH ₂ PO ₄ , K ₃ PO ₄ , K ₂ OsO ₄ , K ₂ TeO ₃ , KHCO ₃ , KBH ₄ , KBF ₄ , KHSO ₄ , KClO ₄ , KIO ₃ , KIO ₄ , KBrO ₃ , KHC ₂ O ₄ , KNO ₂ , K ₂ CO ₃ , KHI ₂ O ₆ , K ₂ S ₂ O ₅ , K ₄ P ₂ O ₇ , KOH, K ₂ SO ₃ , K ₂ B4O ₇ , K ₂ S ₂ O ₈ , potassium formate, potassium oleate, potassium propionate, potassium methoxide, potassium methylmalonate, potassium acetate, potassium citrate , Potassium dihydrogen citrate, potassium tartrate and one or more of the above hydrates, especially when the potassium source is K ₂ CO ₃ , it is more conducive to the formation of KLi ₃ Tm(C ₂ O ₄ ) ₃ .

In a preferred embodiment of the present application, the lithium source is selected from one or more of lithium elemental substance, lithium oxide, or lithium salt, especially when the lithium source is a lithium salt, it is easier to prepare the crystalline material.

In a further preferred embodiment of the present application, the lithium salt is selected from Li ₂ CO ₃ , LiOH, LiBO ₂ , Li ₂ MoO ₄ , Li ₂ SO ₄ , LiBF ₄ , Li ₃ PO ₄ , Li ₂ CuCl ₄ , Li ₂ B _{One or more of 4} O ₇ , C ₂ O ₄ Li ₂ , Li ₂ CrO ₄ , CF ₃ SO ₃ Li and hydrates of the above substances, especially when the lithium salt is Li ₂ CO ₃ Conducive to the generation of crystalline materials.

In a preferred embodiment of the present application, the transition metal source is selected from one or more of cobalt source, nickel source, manganese source, copper source, zinc source, titanium source, vanadium source and chromium source.

In a further preferred embodiment of the present application, the cobalt source is selected from one or more of cobalt element, cobalt oxide or cobalt salt, especially when the cobalt source is a cobalt salt, it is easier to prepare the crystalline material.

In a further preferred embodiment of the present application, the cobalt oxide is selected from one or more of cobalt monoxide, cobalt trioxide or tricobalt tetroxide.

In a further preferred embodiment of the present application, the cobalt salt is selected from cobalt fluoride, cobalt fluoride, cobalt chloride, cobalt chloride, cobalt bromide, cobalt nitrate, cobalt sulfate, cobalt carbonate, cobalt acetate, cobalt oxalate, hexa One or more of cobalt aminochloride or cobalt acetylacetonate and its hydrate, preferably cobalt chloride.

In a preferred embodiment of the present application, the nickel source is selected from elemental nickel, nickel oxide, high nickel oxide, nickel hydroxide, high nickel hydroxide, nickel fluoride, nickel chloride, nickel bromide, nickel nitrate, carbonic acid Nickel, nickel sulfate, nickel acetate, nickel oxalate, nickel bis(hexafluoroethylacetone) nickel, nickel sulfamate, basic nickel carbonate, nickel acetylacetonate dihydrate, nickel trifluoromethanesulfonate, nickel benzenesulfonate , Nickel acetylacetonate or nickel fluoroborate and one or more of its hydrate, preferably nickel chloride.

In a preferred embodiment of the present application, the copper source is selected from elemental copper, cuprous oxide, copper oxide, copper hydroxide, copper fluoride, copper chloride, copper bromide, copper carbonate, basic copper carbonate, nitric acid One or more of copper, copper sulfate, copper acetate, copper oxalate, copper tartrate, copper citrate, copper fluoroborate, copper acetylacetonate or copper gluconate and their hydrates, preferably copper acetate, copper sulfate or chlorine Copper.

In a preferred embodiment of the present application, the zinc source is selected from elemental zinc, zinc oxide, zinc hydroxide, zinc fluoride, zinc chloride, zinc bromide, zinc iodide, zinc sulfate, zinc nitrate, zinc carbonate, One or more of zinc acetate, zinc oxalate, zinc citrate, zinc fluoroborate, zinc tartrate, zinc borate, zinc metaborate, zinc acetylacetonate or zinc gluconate and their hydrates, preferably zinc sulfate or chloride Zinc.

In a preferred embodiment of the present application, the titanium source is selected from elemental titanium, titanium trioxide, titanium dioxide, titanium(III) sulfate, titanium(IV) sulfate, titanium phosphate, sodium fluotitanate, hexafluorotitanic acid, Tetrabutyl titanate, tetraethyl titanate, isopropyl titanate, titanium tetrachloride, titanium trichloride, titanium dihydride, ammonium fluorotitanate, titanium tetrafluoride, titanium dichloride or bis( One or more of acetylacetonyl) isopropyl titanate and its hydrate, preferably titanium tetrafluoride, titanium (III) sulfate or titanium trichloride.

Vanadium sources include selected from elemental vanadium, vanadium trioxide, vanadium dioxide, vanadium pentoxide, vanadium difluoride, vanadium trifluoride, vanadium tetrafluoride, vanadium pentafluoride, vanadium oxyfluoride, vanadium dichloride , Vanadium trichloride, vanadium tetrachloride, vanadium oxychloride, vanadium dibromide, vanadium tribromide, vanadium tetrabromide, ammonium metavanadate, sodium orthovanadate, sodium metavanadate, vanadium acetylacetonate, acetyl One or more of vanadium acetone oxide, vanadium triisopropoxide or vanadium tripropoxide and their hydrates, preferably vanadium dioxide, vanadium pentoxide or vanadium oxyfluoride.

The chromium source is selected from elemental chromium, chromium trioxide, chromium dioxide, chromium trioxide, chromium hydroxide, chromium sulfate, chromite sulfate, lithium chromite, potassium dichromate, sodium dichromate, chromium vanadium, three Chromium fluoride, chromium dichloride, chromium trichloride, chromium bromide, chromium bromide, chromium orthophosphate, chromium metaphosphate, chromium pyrophosphate, chromium acid phosphate, chromium phosphate basic, chromium phosphate phosphate, One or more of chromium nitrate, chromium nitrate, chromium formate, cadmium acetate, chromium acetate or chromium oxalate and their hydrates; preferably chromium hydroxide, chromium dichloride or chromium trichloride.

In a preferred embodiment of the present application, the oxalic acid source is selected from one or more of oxalic acid, sodium oxalate, sodium hydrogen oxalate, potassium oxalate, potassium hydrogen oxalate, ammonium oxalate and ammonium hydrogen oxalate, preferably oxalic acid.

An exemplary method for preparing a crystalline material includes the following steps:

(a) Weigh the lithium source, potassium source, transition metal source and oxalic acid source according to a certain ratio, add the weighed raw materials into the reactor equipped with the solvent, mix them evenly to obtain a mixed solution;

(b) Heating the mixed solution at a temperature of 150-300°C for 4-96h to obtain a crystalline material initial product;

(c) The crystalline material is obtained after washing and drying the initial product of the crystalline material.

It should be noted that the order of raw material addition in step (a) is not particularly limited.

According to the third aspect of the present application, the present application provides the application of the above crystalline material or the crystalline material obtained according to the preparation method provided in the present application in a battery positive active material.

According to the four aspects of the present application, the present application provides a battery positive active material, including the crystalline material provided by the present application or the crystalline material obtained by the preparation method provided by the present application. By using KLi ₃ Tm(C ₂ O ₄ ) ₃ provided in the present application as a positive electrode active material, the capacity of the battery and the chemical performance of the battery can be significantly improved.

According to a fifth aspect of the present application, the present application provides a battery positive electrode material, including the battery positive electrode active material described in the present application.

The battery cathode material provided in this application uses KLi ₃ Tm (C ₂ O ₄ ) crystal material as the cathode active material, so that it can be applied to both lithium ion batteries and potassium ion batteries, and can also significantly improve the two batteries The capacity, effectively improve the chemical performance of the two batteries.

In a preferred embodiment of the present application, the battery cathode material includes KLi ₃ Tm(C ₂ O ₄ ) ₃ crystal material, a cathode conductive agent, and a cathode binder.

The positive electrode conductive agent is to ensure that the positive electrode has good charge and discharge performance. When making the positive electrode, a certain amount of conductive material is usually added to play a role in collecting micro currents between the positive electrode active material and the positive electrode active material and the positive electrode current collector. Reducing the contact resistance of the positive electrode accelerates the moving rate of electrons, and can also effectively increase the migration rate of metal ions in the electrode material, thereby improving the charge and discharge efficiency of the positive electrode. The positive electrode conductive agent may be, but not limited to, at least one of conductive carbon black, conductive carbon spheres, conductive graphite, conductive carbon fiber, carbon nanotubes, graphene, or reduced graphene oxide.

The positive electrode binder can ensure that the positive electrode has a certain bonding strength between the active material particles and between the active particles and the current collector during the use of the positive electrode, and it is conducive to the formation of the SEI film and improves the cycle performance and service life of the positive electrode. The positive electrode binder may be, but not limited to, at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, carboxymethyl cellulose, styrene-butadiene rubber (SBR), or polyolefins.

In a preferred embodiment of the present application, the battery positive electrode material includes KLi ₃ T _m (C ₂ O ₄ ) ₃ 60-90 wt%, positive electrode conductive agent 5-30 wt% and positive electrode binder 5-10 wt%. By optimizing the mass ratio of the positive electrode active material, the positive electrode conductive agent and the positive electrode binder and the types of the positive electrode conductive agent and the positive electrode binder used, the positive electrode active material is better adhered to the positive electrode current collector and the positive electrode is improved The charging and discharging efficiency makes the electrochemical performance of the prepared battery better.

Typical but non-limiting, the content of KLi ₃ T _m (C ₂ O ₄ ) ₃ in the battery positive electrode material is 60wt%, 62wt%, 65wt%, 68wt%, 70wt%, 72wt%, 75wt%, 78wt% , 80wt%, 82wt%, 85wt%, 88wt% or 90wt%; the content of the positive electrode conductive agent is 5wt%, 8wt%, 10wt%, 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt% or 30wt%; the content of the positive electrode binder is, for example, 5wt%, 6wt%, 7wt%, 8wt%, 9wt% or 10wt%.

In another embodiment of the present application, the battery cathode material includes a lithium-deficient cathode active material, KLi ₃ Tm(C ₂ O ₄ ) ₃ , a cathode conductive agent, and a cathode binder.

In the preferred embodiment, the battery cathode material cooperates with each other through the lithium-deficient cathode active material and KLi ₃ Tm(C ₂ O ₄ ) ₃ to provide a sufficient lithium source for the lithium-ion battery cathode active material.

In this preferred embodiment, the roles and types of the positive electrode conductive agent and the positive electrode binder are the same as those described above, and will not be repeated here.

In this preferred embodiment, the lithium-deficient cathode active material is selected from CoSO ₄ F and/or CoPO ₄ .

In a further preferred embodiment of the present application, the battery cathode material includes lithium-deficient cathode active material 40-60wt%, KLi ₃ Tm(C ₂ O ₄ ) ₃ 10-30wt%, cathode conductive agent 5-30wt%, and cathode bonding Agent 5-10wt%. By optimizing the mass ratio of lithium-deficient positive electrode active material, KLi ₃ Tm(C ₂ O ₄ ) ₃ , positive electrode conductive agent and positive electrode binder, and the types of positive electrode conductive agent and positive electrode binder used, it is beneficial to positive electrode activity The material adheres better to the positive electrode current collector, improves the charge and discharge efficiency of the positive electrode, and makes the electrochemical performance of the prepared battery better.

Typical but non-limiting, in the battery cathode material, the content of the lithium-deficient cathode active material is 40wt%, 42wt%, 45wt%, 48wt%, 50wt%, 52wt%, 55wt%, 58wt% or 60wt%; KLi _{The content of 3} T _m (C ₂ O ₄ ) ₃ is 10wt%, 12wt%, 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt% or 30wt%; the content of the positive electrode conductive agent is 5wt% , 8wt%, 10wt%, 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt% or 30wt%; the content of the positive electrode binder is 5wt%, 6wt%, 7wt%, 8wt%, 9wt% Or 10wt%.

In a preferred embodiment of the present application, the lithium-deficient positive active material includes but is not limited to CoPO ₄ or CoSO ₄ F.

According to the sixth aspect of the present application, the present application provides a battery including the crystalline material provided by the present application, the crystalline material obtained by the preparation method provided by the present application, the positive electrode active material of the battery provided by the present application, or the lithium provided by the present application Ion battery.

The potassium ion battery provided by this application uses KLi ₃ Tm(C ₂ O ₄ ) ₃ as a positive electrode active material, which significantly improves the capacity and cycle performance of the potassium ion battery, thereby improving the chemical performance of the potassium ion battery.

In a preferred embodiment of the present application, the battery is a potassium ion battery or a lithium ion battery.

In a preferred embodiment of the present application, when the battery is a potassium ion battery, the potassium ion battery includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode includes a positive electrode material and a positive electrode current collector, wherein the positive electrode material is the first A battery positive electrode material provided in a preferred embodiment.

In a further preferred embodiment of the present application, the positive electrode current collector is selected from one, at least two of aluminum, copper, iron, tin, zinc, nickel, titanium, manganese, lead, antimony, cadmium, gold, bismuth and germanium Alloy or at least two composite materials;

The at least two alloys include but are not limited to copper-aluminum alloys, copper-iron alloys, copper-tin alloys, nickel-titanium alloys, nickel-manganese alloys, nickel-antimony alloys, gold-bismuth alloys, iron-nickel alloys, lead-manganese alloys, and aluminum-nickel alloys.

The at least two composite materials include but are not limited to aluminum-copper composite materials, iron-copper composite materials, copper-tin composite materials, nickel-titanium composite materials, nickel-manganese composite materials, nickel-antimony composite materials, gold-bismuth composite materials, iron-nickel composite materials , Lead-manganese composite materials and aluminum-nickel composite materials.

In a still further preferred embodiment of the present application, the positive electrode current collector is aluminum. When aluminum is used as the current collector of the positive electrode, the cost is lower and the stability of the positive electrode is better.

In a preferred embodiment of the present application, the negative electrode includes a negative electrode material and a negative electrode current collector, and the negative electrode material includes a negative electrode active material, a negative electrode conductive agent, and a negative electrode binder.

The negative electrode active material is the key to ensure that the negative electrode has good charge and discharge performance. The negative electrode active material needs to facilitate the deintercalation and insertion of metal ions. Typical but non-limiting, the negative electrode active material is selected from carbon materials, simple metals, metal alloys, One or more of sulfide, nitride and oxide materials.

The above carbon materials include but are not limited to graphite, carbon black and carbon nanotubes, etc., the elemental metals include but are not limited to copper, tin and antimony, etc., and the metal alloys include but are not limited to copper-nickel alloy, tin-potassium alloy and copper-aluminum alloy; The materials include but are not limited to tungsten sulfide and molybdenum disulfide; the nitrides include but are not limited to lithium copper nitride and lithium cobalt nitride; the oxides include but are not limited to tin oxide and stannous oxide.

The negative electrode conductive agent is to ensure that the negative electrode has good charge and discharge performance. A certain amount of conductive material is usually added when making the negative electrode, and it plays a role in collecting micro currents between the negative electrode active material and between the negative electrode active material and the negative electrode current collector. Reducing the contact resistance of the negative electrode accelerates the moving rate of electrons, and can also effectively increase the migration rate of metal ions in the negative electrode, thereby improving the charge and discharge efficiency of the negative electrode. The negative electrode conductive agent may be, but not limited to, one or more of conductive carbon black, conductive carbon spheres, conductive graphite, carbon nanotubes, conductive carbon fiber, graphene, and reduced graphene oxide.

The negative electrode binder can ensure that the negative electrode has a certain bonding strength between the active material particles and between the active particles and the current collector during use, and it is conducive to the formation of the SEI film and improves the cycle performance and service life of the positive electrode. The positive electrode binder may be, but not limited to, at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, carboxymethyl cellulose, styrene-butadiene rubber (SBR), or polyolefins.

In a preferred embodiment of the present application, the negative electrode material includes negative electrode active material 60-90wt%, negative electrode conductive agent 5-30wt% and negative electrode binder 5-10wt%. Typical but non-limiting, the negative electrode active material accounts for 60wt%, 62wt%, 65wt%, 68wt%, 70wt%, 72wt%, 75wt%, 78wt%, 80wt%, 85wt% or 90wt% ; The negative electrode conductive agent accounts for 5wt%, 8wt%, 10wt%, 12wt%, 15wt%, 18wt%, 20wt%, 25wt% or 30wt%; the negative electrode binder accounts for 5wt%, 6wt%, 7wt %, 8wt%, 9wt% or 10wt%.

By optimizing the mass ratio of the negative electrode active material, the negative electrode conductive agent and the negative electrode binder, and the types of the negative electrode conductive agent and the negative electrode binder used, the negative electrode active material is better adhered to the negative electrode current collector and the negative electrode is improved. The charge and discharge efficiency of the battery makes the electrochemical performance of the prepared battery more excellent.

In a preferred embodiment of the present application, the negative electrode current collector is selected from one, at least two of aluminum, copper, iron, tin, zinc, nickel, titanium, manganese, lead, antimony, cadmium, gold, bismuth and germanium Kinds of alloys or at least two kinds of composite materials.

In a still further preferred embodiment of the present application, the negative electrode current collector is aluminum. When aluminum is used as the negative electrode current collector, the cost is lower and the stability of the negative electrode is better.

In a preferred embodiment of the present application, the separator is selected from one or more composite films of porous polymer films, inorganic porous films, glass fiber papers, or porous ceramic films.

In a further preferred embodiment of the present application, the porous polymer film is selected from one of porous polypropylene film, porous polyethylene film or porous composite polymer film.

The porous composite polymer film includes but is not limited to porous polyethylene and polypropylene composite films.

In a preferred embodiment of the present application, the electrolyte includes an electrolyte and an electrolyte solvent, wherein the electrolyte is a sodium salt, and the electrolyte solvent is an organic solvent.

The electrolyte is the medium used by the chemical battery, which provides ions for the normal operation of the chemical battery, and ensures that the chemical reaction occurring in the work is reversible.

In a further preferred embodiment of the present application, the volume concentration of potassium salt is 0.1-10 mol/L. By controlling the volume concentration of potassium salt in the electrolyte, the migration rate of ions in the electrolyte is ensured, thereby ensuring the electrochemical performance of the battery.

Typical but non-limiting, the volume concentration of potassium salt in the electrolyte is 0.1, 0.2, 0.5, 0.8, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 mol/L.

In a preferred embodiment of the present application, the potassium salt is selected from potassium hexafluorophosphate, potassium chloride, potassium fluoride, potassium sulfate, potassium carbonate, potassium phosphate, potassium nitrate, potassium difluorooxalate borate, potassium pyrophosphate, Potassium dodecylbenzenesulfonate, potassium dodecyl sulfate, tripotassium citrate, potassium metaborate, potassium borate, potassium molybdate, potassium tungstate, potassium bromide, potassium nitrite, potassium iodate, potassium iodide, Potassium silicate, potassium lignosulfonate, potassium oxalate, potassium aluminate, potassium methanesulfonate, potassium acetate, potassium dichromate, potassium hexafluoroarsenate, potassium tetrafluoroborate, potassium perchlorate, trifluoromethanesulfonyl One or more of potassium imine, KCF ₃ SO ₃ and KN(SO ₂ CF ₃ ) ₂ , especially when the potassium salt is potassium hexafluorophosphate, the migration efficiency of potassium ions in the electrolyte is higher and more Helps to improve the chemical performance of potassium ion batteries.

In a preferred embodiment of the present application, the organic solvent is selected from one or more of ester solvents, sulfone solvents, ether solvents and nitrile solvents.

In a preferred embodiment of the present application, the organic solvent includes but is not limited to propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), methyl ethyl carbonate Ester (EMC), methyl formate (MF), methyl acetate (MA), N,N-dimethylacetamide (DMA), fluoroethylene carbonate (FEC), methyl propionate (MP), propylene Ethyl acetate (EP), ethyl acetate (EA), γ-butyrolactone (GBL), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2MeTHF), 1,3-dioxolane (DOL), 4-methyl-1,3-dioxolane (4MeDOL), dimethoxymethane (DMM), 1,2-dimethoxypropane (DMP), triethylene glycol dimethyl ether (DG), dimethicone Methyl sulfone (MSM), dimethyl ether (DME), vinyl sulfite (ES), propylene sulfite (PS), dimethyl sulfite (DMS), diethyl sulfite (DES), crown ether (12-crown-4), 1-ethyl-3-methylimidazole-hexafluorophosphate, 1-ethyl-3-methylimidazole-tetrafluoroborate, 1-ethyl-3-methyl Imidazole-bistrifluoromethylsulfonimide salt, 1-propyl-3-methylimidazole-hexafluorophosphate, 1-propyl-3-methylimidazole-tetrafluoroborate, 1-propyl -3-methylimidazole-bis-trifluoromethylsulfonimide salt, 1-butyl-1-methylimidazole-hexafluorophosphate, 1-butyl-1-methylimidazole-tetrafluoroborate , 1-butyl-1-methylimidazole-bistrifluoromethylsulfonimide salt, N-butyl-N-methylpyrrolidine-bistrifluoromethylsulfonimide salt, 1-butyl -1-Methylpyrrolidine-bistrifluoromethylsulfonimide salt, N-methyl-N-propylpyrrolidine-bistrifluoromethylsulfonimide salt, N-methyl, propylpiperidine -One or more of bistrifluoromethylsulfonimide salt and N-methyl, butylpiperidine-bistrifluoromethylsulfonimide salt.

In a preferred embodiment of the present application, the potassium salt as the electrolyte is not particularly limited as long as it can dissociate into potassium ions and anions.

In a preferred embodiment of the present application, additives are added to the electrolyte. By adding additives to the electrolyte, the cycle stability of the potassium ion battery is improved. The additive is selected from one or more of esters, sulfones, ethers, nitriles or olefins.

In a preferred embodiment of the present application, the additive amount of the electrolyte is 0.1-20 wt%. By controlling the amount of additives added in the electrolyte, it is convenient for it to form a stable solid electrolyte membrane on the surface of the negative electrode current collector, thereby increasing the service life of the battery. Typical but non-limiting, in the electrolyte, the addition amount is 0.1wt%, 0.2wt%, 0.5wt%, 0.8wt%, 1wt%, 2wt%, 5wt%, 8wt%, 10wt%, 12wt %, 15wt%, 18wt% or 20wt%.

In a further preferred embodiment of the present application, the additive is selected from fluoroethylene carbonate, vinylene carbonate, ethylene ethylene carbonate, 1,3-propane sultone, 1,4-butane sultone, Vinyl sulfate, propylene sulfate, ethylene sulfate, vinyl sulfite, propylene sulfite, dimethyl sulfite, diethyl sulfite, ethylene sulfite, methyl chloroformate, di Methyl sulfoxide, anisole, acetamide, diazabenzene, m-diazepine, crown ether 12-crown-4, crown ether 18-crown-6, 4-fluoroanisole, fluorochain Ether, difluoromethyl ethylene carbonate, trifluoromethyl ethylene carbonate, chloro ethylene carbonate, brominated ethylene carbonate, trifluoroethylphosphonic acid, bromobutyrolactone, fluoroacetic acid ethyl ethyl Alkanes, phosphates, phosphites, phosphazenes, ethanolamines, carbamide, cyclobutylsulfone, 1,3-dioxolane, acetonitrile, long-chain olefins, aluminum oxide, magnesium oxide, barium oxide , Sodium carbonate, calcium carbonate, carbon dioxide, sulfur dioxide and lithium carbonate one or more.

In a preferred embodiment of the present application, the preparation method of the potassium ion battery provided by the present application includes the following steps: assembling the positive electrode, the negative electrode, the separator, and the electrolyte to obtain a potassium ion battery.

The preparation method of the potassium ion battery provided by the present application is simple in process, suitable for industrial production, and can significantly improve the preparation efficiency and reduce the production cost.

In a preferred embodiment of the present application, the preparation method of the potassium ion battery is prepared according to the following steps:

(a) Preparation of positive electrode: KLi ₃ T _m (C ₂ O ₄ ) ₃ , positive electrode conductive agent and positive electrode binder are added to the positive electrode solvent and mixed evenly to make a positive electrode slurry, and then the positive electrode slurry is evenly coated on the positive electrode The surface of the current collector is dried and the positive electrode is obtained;

(b) Preparation of negative electrode: The negative electrode active material, negative electrode conductive agent and negative electrode binder are added to the negative electrode solvent and mixed uniformly to make a negative electrode slurry, and then the negative electrode slurry is evenly coated on the surface of the negative electrode current collector and dried to obtain a negative electrode ;

(c) Preparation of electrolyte: potassium salt and optional additives are added to the electrolyte solvent and mixed evenly to obtain electrolyte;

(d) Assemble the positive electrode, negative electrode, separator and electrolyte to obtain a potassium ion battery.

In a preferred embodiment of the present application, the positive electrode solvent is a solvent capable of dissolving the positive electrode material, including but not limited to nitromethylpyrrolidone.

In a preferred embodiment of the present application, the negative electrode solvent is a solvent capable of dissolving the negative electrode material, including but not limited to nitromethylpyrrolidone.

In a preferred embodiment of the present application, when the battery is a lithium ion battery, the lithium ion battery includes a positive electrode, a negative electrode, a separator, and an electrolyte, wherein the positive electrode, the negative electrode, and the separator are the same as the positive electrode and the negative electrode in the above potassium ion battery It is the same as the separator, and will not be repeated here. The difference from the above-mentioned potassium ion battery is that the solute of its electrolyte is a lithium salt, which is selected from lithium trifluoromethanesulfonate and di(trifluoromethyl) (Sulfonic acid) lithium imide and its derivatives, lithium perfluoroalkyl phosphate, lithium tetrafluorooxalate phosphate, lithium bisoxalate borate, lithium tris(catechol) phosphate and sulfonated polysulfonamide lithium salt, LiPF ₆ , LiClO _{4. One} or more of LiCoO ₂ , LiBF ₆ , LiAsF ₆ , LiNO ₃ , LiCO ₃ or LiCl, especially when the lithium salt is potassium hexafluorophosphate, it is more conducive to the migration of ions in the electrolyte, thereby improving lithium Electrochemical performance of ion batteries.

In another preferred embodiment of the present application, the positive electrode material of the lithium ion battery is the foregoing positive electrode material composed of lithium-deficient positive electrode active material, KLi ₃ Co(C ₂ O ₄ ) ₃ , positive electrode conductive agent and positive electrode binder, and the rest The positive electrode current collector, the negative electrode, the separator, and the electrolyte are the same as the positive electrode current collector, the negative electrode, the separator, and the electrolyte in the first preferred embodiment of the lithium-ion battery, and are not repeated here.

In the preferred embodiment, the lithium-ion battery uses a lithium-deficient cathode active material and KLi ₃ Co(C ₂ O ₄ ) ₃ as a cathode active material, which provides a sufficient lithium source for the lithium-ion battery cathode active material, thereby effectively improving Lithium-ion battery capacity.

In a preferred embodiment of the present application, the present application provides that the preparation method of the above-mentioned lithium ion battery is the same as the preparation method of the potassium ion battery, which will not be repeated here.

According to the seventh aspect of the present application, the present application provides an electric device including the crystalline material provided by the present application, the crystalline material obtained by the preparation method provided by the present application, the battery positive electrode active material provided by the present application, and the application provided by the present application Positive battery material or the battery provided in this application.

The technical solution provided by the present application will be further described below in conjunction with examples and comparative examples.

Example 1

This embodiment provides a KLi ₃ Co(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.23793g CoCl ₂ ·6H ₂ O, 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into 25mL polytetrafluoroethylene inner village In the hydrothermal reaction kettle, stir and mix evenly, tighten the reaction kettle, put it in an oven at 190 ℃, the reaction is cooled to room temperature for 4h, take out the solid product in the reaction kettle, wash, filter with suction, and dry to obtain KLi ₃ Co( C ₂ O ₄ ) ₃ crystal particles.

Example 2

This example provides a KLi ₃ Co(C ₂ O ₄ ) ₃ crystalline material. The preparation method differs from Example 1 in that the K ₂ CO ₃ is 0.22642 g.

Example 3

This example provides a KLi ₃ Co(C ₂ O ₄ ) ₃ crystalline material. The preparation method differs from Example 1 in that the reaction temperature is 185° C. and the reaction time is 24 h.

Example 4

This example provides a KLi ₃ Co(C ₂ O ₄ ) ₃ crystalline material. The preparation method is different from that in Example 1 in that CoCl ₂ .6H ₂ O is 0.11897 g.

Example 5

This example provides a KLi ₃ Co(C ₂ O ₄ ) ₃ crystalline material. The preparation method differs from Example 1 in that the H ₂ C ₂ O ₄ .2H ₂ O is 0.63035 g.

Example 6

This embodiment provides a KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.23793g NiCl ₂ ·6H ₂ O, 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into 25ml polytetrafluoroethylene inner village In the hydrothermal reaction kettle, stir and mix evenly. Tighten the reaction kettle and put it in an oven at 180°C. The reaction is cooled to room temperature for 48 hours. The solid product in the reaction kettle is taken out, washed, filtered by suction, and dried to obtain KLi ₃ Ni (C ₂ O ₄ ) ₃ crystal particles.

Example 7

This embodiment provides a KLi ₃ Mn(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.12584g MnCl ₂ ·4H ₂ O, 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into 25mL polytetrafluoroethylene inner village In the hydrothermal reaction kettle, stir and mix evenly, screw the reaction kettle tightly, put it in an oven at 180°C, react for 48 hours, cool to room temperature, take out the solid product in the reaction kettle, wash, filter with suction, and dry to obtain KLi ₃ Mn (C ₂ O ₄ ) ₃ crystal particles.

Example 8

This embodiment provides a KLi ₃ Cu(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.1325g CuCl ₂ · 2H ₂ O, 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into 25mL polytetrafluoroethylene inner village In the hydrothermal reaction kettle, stir and mix evenly. Tighten the reaction kettle and put it in an oven at 180°C. The reaction is cooled to room temperature for 48 hours. The solid product in the reaction kettle is taken out, washed, suction filtered, and dried to obtain KLi ₃ Cu (C ₂ O ₄ ) ₃ crystal particles.

Example 9

This embodiment provides a KLi ₃ Zn(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.11637g ZnCl ₂ , 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into the hydrothermal reaction of 25mL polytetrafluoroethylene inner village In the kettle, stir and mix evenly. Tighten the reaction kettle and put it in an oven at 180°C. After 48 hours of reaction, cool to room temperature. Take out the solid product in the reaction kettle, wash, filter with suction, and dry to obtain KLi ₃ Zn(C ₂ O ₄ ) ₃ crystal particles.

Example 10

This embodiment provides a KLi ₃ Ti(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.15341g TiCl ₃ , 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into the hydrothermal reaction of 25mL polytetrafluoroethylene inner village In the kettle, stir and mix evenly. Tighten the reaction kettle and put it in an oven at 200°C. The reaction is cooled to room temperature for 72 hours. Take out the solid product in the reaction kettle, wash, filter with suction, and dry to obtain KLi ₃ Ti(C ₂ O ₄ ) ₃ crystal particles.

Example 11

This embodiment provides a KLi ₃ V(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.15594g VOF ₂ , 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into the hydrothermal reaction of 25mL polytetrafluoroethylene inner village In the kettle, stir and mix evenly. Tighten the reaction kettle and put it in an oven at 220°C. After 48 hours of reaction, cool to room temperature. Take out the solid product in the reaction kettle, wash, filter with suction, and dry to obtain KLi ₃ V(C ₂ O ₄ ) ₃ crystal particles.

Example 12

This embodiment provides a KLi ₃ Cr(C ₂ O ₄ ) ₃ crystal material. The preparation method includes the following steps:

Put 0.12299g CrCl ₂ ·4H ₂ O, 0.14778g Li ₂ CO ₃ , 0.13821g K ₂ CO ₃ , 0.50428g H ₂ C ₂ O ₄ · 2H ₂ O and 10g H ₂ O into 25mL polytetrafluoroethylene inner village In the hydrothermal reaction kettle, stir and mix evenly, tighten the reaction kettle, put it in an oven at 180°C, react for 48 hours, cool to room temperature, take out the solid product in the reaction kettle, clean, suction filter, and dry to obtain KLi ₃ Cr (C ₂ O ₄ ) ₃ crystal particles.

Example 13

This embodiment provides a potassium ion half-cell, which is prepared according to the following steps:

(1) Preparation of battery negative electrode: roll the metal potassium block into a metal potassium sheet, cut into 12mm diameter discs, and use it as a negative electrode;

(2) Preparation of the diaphragm: the glass fiber diaphragm is cut into 16 mm diameter discs, which are used as the diaphragm after drying;

(3) Preparation of battery positive electrode: Add 0.8 g of ball-milled KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder, 0.15 g of conductive graphite, and 0.05 g of polytetrafluoroethylene to 1 mL of N-methylpyrrolidone solution, and grind it thoroughly A uniform slurry is obtained; then the slurry is evenly coated on the surface of the carbon-coated aluminum foil and vacuum dried. The dried electrode sheet was cut into a 10 mm diameter disc, which was used as a positive electrode after compaction; wherein, KLi ₃ Co(C ₂ O ₄ ) ₃ was the crystal provided in Example 1;

(4) Preparation of electrolyte: weigh 1.8g potassium hexafluorophosphate into 10mL mixed solvent of trimethylacetyl chloride and dimethyl carbonate (volume ratio 1:1), stir until potassium hexafluorophosphate is completely dissolved, After fully stirred evenly, it is used as an electrolyte (electrolyte concentration is 1mol/L).

(5) Battery assembly: In an inert gas-protected glove box, the above-mentioned prepared negative electrode current collector, separator, and battery positive electrode are stacked closely in sequence, and electrolyte is added dropwise to completely infiltrate the separator, and then the above-mentioned stacked part is encapsulated into a button type The battery casing completes the battery assembly to obtain a potassium ion half-cell.

Example 14

This embodiment provides a potassium ion full battery, which is prepared according to the following steps:

(1) Preparation of battery negative electrode: Add 0.8g activated carbon, 0.1g carbon black and 0.1g polyvinylidene fluoride to 2ml of N-methylpyrrolidone solution, fully grind to obtain a uniform slurry; then uniformly apply the slurry to aluminum foil Surface (ie, negative electrode current collector) and vacuum dried. Cut the dried electrode sheet into 10mm diameter discs and use it as a battery negative electrode after compaction;

(3) Preparation of battery positive electrode: 0.8g of ball-milled KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder, 0.15g of conductive graphite and 0.05g of polytetrafluoroethylene are added to 1mL of N-methylpyrrolidone solution, and fully ground to obtain Uniform slurry; then uniformly apply the slurry to the surface of carbon-coated aluminum foil and vacuum dry. Cut the dried electrode sheet into 10mm diameter discs and use it as a positive electrode after compaction;

(5) Battery assembly: In an inert gas-protected glove box, the above-mentioned prepared negative electrode current collector, separator, and battery positive electrode are stacked closely in sequence, and electrolyte is added dropwise to completely infiltrate the separator, and then the above-mentioned stacked part is encapsulated into a button type The battery casing completes the battery assembly, and the potassium ion full battery is obtained.

Example 15

This embodiment provides a potassium ion full battery, which differs from Embodiment 14 in that the solvent used in the electrolyte is trimethylacetyl chloride, and the rest is the same as in Embodiment 14, which will not be repeated here.

Example 16

This example provides a potassium ion full battery, which differs from Example 14 in that the solvents used in the electrolyte are ethyl methyl carbonate, dimethyl carbonate, and ethylene carbonate (volume ratio 1:1:1) The rest is the same as that in Embodiment 14, and will not be repeated here.

Example 17

This embodiment provides a potassium ion full battery, which is different from Embodiment 14 in that the negative electrode active material is natural graphite, and the rest is the same as Embodiment 14, which will not be repeated here.

Example 18

This embodiment provides a potassium ion full battery, which is different from Embodiment 14 in that the electrolyte concentration is 0.8 mol/L, and the rest is the same as Embodiment 14, which will not be repeated here.

Example 19

This embodiment provides a potassium ion full battery, which is different from Embodiment 14 in that the negative electrode current collector is aluminum, and the rest is the same as Embodiment 14, which will not be repeated here.

Example 20

This example provides a potassium ion full battery, which is different from Example 14 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.75 g, conductive graphite is 0.15 g, and polytetrafluoroethylene Ethylene is 0.1 g, and the rest are the same as in Example 14, and will not be repeated here.

Example 21

This example provides a potassium ion full battery, which is different from Example 14 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.85 g, conductive graphite is 0.1 g, and polytetrafluoroethylene Ethylene is 0.05g, and the rest are the same as in Example 14, and are not repeated here.

Example 22

This example provides a potassium ion full battery, which is different from Example 14 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.5 g, conductive graphite is 0.3 g, and polytetrafluoroethylene Ethylene is 0.2g, and the rest are the same as in Example 14, and will not be repeated here.

Example 23

This example provides a potassium ion full battery, which is different from Example 14 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.95 g, conductive graphite is 0.02 g, and polytetramethylene The vinyl fluoride is 0.03g, and the rest are the same as in Example 14, and will not be repeated here.

Comparative Example 1

This comparative example provides a potassium ion full battery, which is different from Example 14 in that KMnO _{2 is used} instead of KLi ₃ Co(C ₂ O ₄ ) ₃ as the positive electrode active material, and the rest are the same as in Example 14, I will not repeat them here.

Comparative Example 2

This comparative example provides a potassium ion full battery, which differs from Example 14 in that K ₃ V ₂ (PO ₄ ) ₂ F _{3 is used} instead of KLi ₃ Co(C ₂ O ₄ ) ₃ as the positive electrode active material The rest are the same as in Embodiment 14, and will not be repeated here.

Example 24

This embodiment provides a lithium ion half-cell, which is prepared according to the following steps:

(1) Battery negative electrode: commercial metal lithium sheet;

(3) Preparation of battery positive electrode: Add 0.8 g of ball-milled KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder, 0.15 g of conductive carbon black, and 0.05 g of polyvinylidene fluoride to 1 mL of N-methylpyrrolidone solution, and grind it thoroughly A uniform slurry is obtained; then the slurry is evenly coated on the surface of the carbon-coated aluminum foil and vacuum dried. Cut the dried electrode sheet into 10mm diameter discs and use it as a positive electrode after compaction;

(4) Preparation of electrolyte: Weigh 1.5g of lithium hexafluorophosphate into a mixed solvent of 10mL of ethylene carbonate and dimethyl carbonate (volume ratio is 1:1), stir until lithium hexafluorophosphate is completely dissolved, fully stirred and evenly used as electrolyte reserve (The electrolyte concentration is 1 mol/L).

(5) Battery assembly: In an inert gas-protected glove box, the above-mentioned prepared negative electrode current collector, separator, and battery positive electrode are stacked closely in sequence, and electrolyte is added dropwise to completely infiltrate the separator, and then the above-mentioned stacked part is encapsulated into a button type The battery casing completes the battery assembly to obtain a lithium ion half-cell.

Example 25

This embodiment provides a lithium ion full battery, which is prepared according to the following steps:

(1) Preparation of battery negative electrode: Add 0.85g activated carbon, 0.1g carbon black and 0.05g polyvinylidene fluoride to 2mL of N-methylpyrrolidone solution, fully grind to obtain a uniform slurry; then uniformly apply the slurry to aluminum foil Surface (ie, negative electrode current collector) and vacuum dried. Cut the dried electrode sheet into 10mm diameter discs and use it as a battery negative electrode after compaction;

Example 26

This example provides a lithium ion full battery, which differs from Example 25 in that the solvents used in the electrolyte are ethylene carbonate and diethyl carbonate (volume ratio 1:3), and the rest are the same as in Example 25 The same, no more details here.

Example 27

This embodiment provides a lithium-ion full battery, which is different from Embodiment 25 in that the solvents used in the electrolyte are ethyl methyl carbonate, dimethyl carbonate, and ethylene carbonate (volume ratio 1:1:2 ), the rest are the same as those in Embodiment 25, and will not be repeated here.

Example 28

This embodiment provides a lithium ion full battery, which is different from Embodiment 25 in that the negative electrode active material is spherical graphite, and the rest are the same as those in Embodiment 25, which will not be repeated here.

Example 29

This embodiment provides a lithium ion full battery, which is different from Embodiment 25 in that the negative electrode active material is activated carbon fiber, and the rest are the same as those in Embodiment 25, which will not be repeated here.

Example 30

This embodiment provides a lithium ion full battery, which is different from Embodiment 25 in that the electrolyte concentration is 1.5 mol/L, and the rest are the same as those in Embodiment 25, which will not be repeated here.

Example 31

This embodiment provides a lithium ion full battery, which is different from Embodiment 25 in that the negative electrode current collector is aluminum, and the rest are the same as those in Embodiment 25, which will not be repeated here.

Example 32

This example provides a lithium ion full battery, which is different from Example 25 in that the solvent used in the electrolyte is ethylene carbonate and diethyl carbonate (volume ratio 2:1), and the rest are the same as Example 25 The same, no more details here.

Example 33

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.75 g, conductive carbon black is 0.15 g, and The vinyl fluoride is 0.1 g, and the rest are the same as in Example 25, and will not be repeated here.

Example 34

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.9 g, conductive carbon black is 0.05 g, and The vinyl fluoride is 0.05g, and the rest are the same as those in Example 25, which will not be repeated here.

Example 35

This embodiment provides a lithium ion full battery, which is different from Embodiment 25 in that KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.95 g, conductive carbon black is 0.02 g, and polyvinylidene fluoride is 0.03 g, the rest are the same as those in Embodiment 25, and will not be repeated here.

Example 36

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that in the positive electrode material, KLi ₃ Co(C ₂ O ₄ ) ₃ is 0.5 g, conductive carbon black is 0.3 g, and The vinyl fluoride is 0.2 g, and the rest are the same as those in Example 25, which will not be repeated here.

Comparative Example 3

This comparative example provides a lithium ion full battery, which differs from Example 25 in that LiMn ₂ O _{4 is used} instead of KLi ₃ Co(C ₂ O ₄ ) ₃ as the positive electrode active material, and the rest are the same as in Example 25 The same, no more details here.

Comparative Example 4

This comparative example provides a lithium ion full battery, which is different from Example 25 in that LiCoO _{2 is used} instead of KLi ₃ Co(C ₂ O ₄ ) ₃ as the positive electrode active material, and the rest are the same as in Example 25. I will not repeat them here.

Example 37

This example provides a lithium ion full battery, which is different from Example 25 in that the positive electrode material is 0.3 g of ball-milled KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder, 0.4 g CoSO ₄ F, 0.2g conductive carbon black and 0.1g polyvinylidene fluoride, the rest are the same as in Example 25, and will not be repeated here.

Example 38

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that the cathode material is 0.05 g of ball-milled KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder, 0.65 g CoSO ₄ F, 0.2g conductive carbon black and 0.1g polyvinylidene fluoride, the rest are the same as in Example 25, and will not be repeated here.

Example 39

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that the positive electrode material is 0.5 g KLi ₃ Co(C ₂ O ₄ ) ₃ crystal powder after ball milling, 0.2 g CoSO ₄ F, 0.2g conductive carbon black and 0.1g polyvinylidene fluoride, the rest are the same as in Example 25, and will not be repeated here.

Comparative Example 5

This embodiment provides a lithium ion full battery, which differs from Embodiment 25 in that the cathode material is 0.8g CoSO ₄ F, 0.15g conductive carbon black, and 0.05g polyvinylidene fluoride, and the rest are the same as the embodiment 25 is the same and will not be repeated here.

Test Example 1

The KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles prepared in Example 1-5 were subjected to copper target XRD test, and the results showed that KLi ₃ Co(C ₂ O ₄ ) ₃ crystals were prepared in Example 1-5. The crystal form of the particles can be consistent with the KLi ₃ Co(C ₂ O ₄ ) ₃ crystal form.

2 is a comparison chart of the XRD of the KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles prepared in Example 1 and the standard KLi ₃ Co(C ₂ O ₄ ) ₃ crystal, where the experimental value diffraction line represents the example The diffraction spectrum of 1. The theoretical diffraction line represents the diffraction spectrum of the standard KLi ₃ Co(C ₂ O ₄ ) ₃ crystal. It can be seen from FIG. 2 that the XRD spectrum of the product prepared in Example 1 is completely consistent with the XRD spectrum of the standard KLi ₃ Co(C ₂ O ₄ ) ₃ crystal, and there are basically no peaks appearing, which shows that the preparation of Embodiment 1 KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles with high purity were obtained.

Test Example 2

The yields of KLi ₃ Co(C ₂ O ₄ ) ₃ in the products prepared in Examples 1-5 were measured respectively. Taking the complete conversion of cobalt into the target product as the theoretically calculated product quality, the yield = the experimentally obtained product quality/the theoretically calculated product quality. The results are shown in Table 1.

Table 1 KLi ₃ Co(C ₂ O ₄ ) ₃ yield data table prepared in Examples 1-5

A	产率(％)Yield(%)
实施例1Example 1	9898
实施例2Example 2	9595
实施例3Example 3	9090
实施例4Example 4	9999
实施例5Example 5	9797

It can be seen from Table 1 that the yields of the KLi ₃ Co(C ₂ O ₄ ) ₃ crystal materials provided in Examples 1-5 are all higher than 90%, which indicates that when preparing the crystal materials, the potassium source, lithium source, The molar ratio of cobalt source and oxalic acid is (1-20): (1-40): (1-2): (2-20), the yield of the obtained KLi ₃ Co(C ₂ O ₄ ) ₃ crystal material is more high.

Test Example 3

The KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles prepared in Example 6 were subjected to copper target XRD test. FIG. 3 is the XRD and standard of the KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles prepared in Example 6 KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal diffraction chart, where the experimental value diffraction line represents the diffraction spectrum of Example 6, and the theoretical value diffraction line represents the diffraction of the standard KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal Spectra. It can be seen from FIG. 3 that the XRD spectrum of the product prepared in Example 6 is completely consistent with the XRD spectrum of the standard KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal, and there is basically no impurity peaks, which shows that the preparation of Embodiment 6 KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles with high purity were obtained.

Test Example 4

The KLi ₃ Co(C ₂ O ₄ ) ₃ crystal particles and KLi ₃ Ni(C ₂ O ₄ ) ₃ crystal particles prepared in Example 1 and Example 6 were subjected to thermogravimetric (TG) and differential scanning calorimetry ( DSC) test. Figures 4 and 5 are the thermogravimetric (TG) and differential scanning calorimetry (DSC) curves of the crystals prepared in Example 1 and Example 6, respectively. It can be seen from the figure that KLi ₃ Co(C ₂ O ₄ ) ₃ and KLi ₃ Ni(C ₂ O ₄ ) ₃ can be stabilized to about 320 ℃ and 300 ℃, respectively; when further heated, the two significantly lose weight, and It is accompanied by an exotherm; when heated to 600°C, the weight loss of the sample is about 62-65% of the initial weight.

Test Example 5

The potassium ion half-cell provided in Example 13 was subjected to constant current charge and discharge performance test, and the results are shown in FIG. 6. Among them, the test conditions are:

1. Standard charging:

Ambient temperature 25±2℃

Constant current charging

Constant current: 150mA/g, protection condition: cut-off voltage ≥4.5V

Let stand for 2 minutes

2. Standard discharge:

Ambient temperature 25±2℃

Constant current discharge

Constant current: 150mA/g, protection condition: cut-off voltage ≤1.5V

Let stand for 2 minutes

It can be seen from FIG. 6 that the potassium ion half-cell provided in Example 13 has excellent cycle stability.

Test Example 6

The potassium ion full batteries provided in Examples 14-23 and Comparative Examples 1-2 were subjected to capacity and cycle stability tests. The results are shown in Table 2. Among them, the charge cut-off voltage is 4.5V, the discharge cut-off voltage is 1.5V, and the charge and discharge current is 100mA/g.

Table 2 Potassium ion full cell electrochemical performance data table

As can be seen from the comparison between Examples 14-21 and Comparative Examples 1-2 in Table 2, the specific capacities of the potassium ion batteries provided in Examples 14-21 are all higher than 130mAh/g, and the capacity retention rate after 100 cycles are all higher than 80 %, which shows that the potassium ion batteries provided in Examples 14-21 have higher specific capacity and excellent cycle stability.

It can be seen from the comparison between Examples 14-21 and Examples 22-23 that by controlling the battery cathode material KLi ₃ Co(C ₂ O ₄ ) ₃ is 60-90wt%, the cathode conductive agent is 5-30wt% and the cathode The binder is 5-10wt%, the specific capacity of the produced potassium ion battery is higher, and the cycle stability is better.

Test Example 7

The lithium ion half-cell provided in Example 24 was subjected to constant current charge and discharge performance test, and the results are shown in FIG. 7. Among them, the test conditions are:

1. Standard charging:

Ambient temperature 25±2℃

Constant current charging

Constant current: 300mA/g, protection condition: cut-off voltage ≥4.5V

Let stand for 2 minutes

2. Standard discharge:

Ambient temperature 25±2℃

Constant current discharge

Constant current: 300mA/g, protection condition: cut-off voltage ≤1.5V

Let sit for 2 minutes

It can be seen from FIG. 7 that the lithium ion half-cell provided in Example 24 has excellent cycle stability.

Test Example 8

The lithium ion full batteries provided in Examples 25-36 and Comparative Examples 3-4 were subjected to capacity and cycle stability tests. The results are shown in Table 3. Among them, the charge cut-off voltage is 4.5V, and the discharge cut-off voltage is 1.5V. The charge and discharge current is 100mA/g.

Table 3 Lithium ion full battery electrochemical performance data table

From the comparison of Examples 25-34 and Comparative Examples 3-4 in Table 3, it can be seen that the specific discharge capacities of the lithium ion batteries provided in Examples 25-34 are not less than 145 mAh, and the capacity retention rate after 100 cycles Above 80%, this shows that the lithium ion batteries provided in Examples 25-34 not only have a higher specific capacity for first discharge, but also have excellent cycle stability.

From the comparison between Examples 25-34 and Examples 35-36, it can be seen that the specific discharge capacity of the lithium ion battery provided by Examples 25-34 and the capacity retention rate after 100 cycles are significantly higher than those of Example 35- 36. This shows that the lithium ion battery provided in this application, when the cathode material, KLi ₃ Co (C ₂ O ₄ ) ₃ is 60-90wt%, the cathode conductive agent is 5-30wt% and the cathode binder is 5- 10wt%, the specific capacity of the manufactured lithium ion battery is higher, and the cycle stability is better.

Test Example 9

The lithium ion full batteries provided in Examples 37-39 and Comparative Example 5 were subjected to capacity and cycle stability tests. The results are shown in Table 4. Among them, the charge cut-off voltage is 4.5V, and the discharge cut-off voltage is 1.5V. The charge and discharge current is 100mA/g.

Table 4 Lithium ion full cell electrochemical performance data table

Group

First discharge specific capacity

100 times capacity retention

A	(mAh/g)(mAh/g)	率(％)rate(%)
实施例37Example 37	9090	9292
实施例38Example 38	6464	9595
实施例39Example 39	9292	8383
对比例5Comparative Example 5	4646	5151

From the comparison between Example 37 and Comparative Example 5 in Table 4, it can be seen that by adding KLi ₃ CoC ₂ O ₄ ) ₃ to CoSO ₄ F as a cathode active material in the cathode material of a lithium ion full battery, it can be used significantly as a cathode active material Improve the specific discharge capacity of lithium ion batteries for the first time.

From the comparison between Example 37 and Examples 38-39 in Table 4, it can be seen that when the cathode material of the lithium ion battery, the lithium-deficient cathode active material is 40-60wt%, and KLi ₃ Co(C ₂ O ₄ ) ₃ is 10 When the -30wt%, the positive electrode conductive agent is 5-30wt% and the positive electrode binder is 5-10wt%, the first discharge specific capacity of the manufactured lithium ion battery is higher, and the cycle stability is better.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not deviate from the essence of the corresponding technical solutions of the technical solutions of the embodiments of the present application. range.

Claims

A crystalline material, characterized in that the molecular formula of the crystalline material is KLi 3 Tm(C 2 O 4 ) 3 , Tm is a transition metal, and the transition metal is selected from Co, Ni, Mn, Cu, Zn, Ti, At least one of V and Cr.
The crystalline material according to claim 1, wherein the KLi 3 Tm(C 2 O 4 ) 3 is a trigonal crystal, the space group is R-3c, and Tm is respectively connected to six oxygens from oxalate to form Octahedron.
A method for preparing a crystalline material, characterized in that it includes the following steps: a solvothermal reaction is performed on a potassium source, a lithium source, a transition metal source and an oxalic acid source to obtain KLi 3 Tm(C 2 O 4 ) 3 , and Tm is a transition metal ;

Wherein, the transition metal source is selected from at least one of cobalt source, nickel source, manganese source, copper source, zinc source, titanium source, vanadium source and chromium source.
The preparation method according to claim 3, wherein the molar ratio of the potassium source, lithium source, transition metal source and oxalic acid source is (1-20): (1-40): (1-2): ( 2-20), preferably (1-2): (1-4): (1-2): (2-5);

Preferably, the solvent for the solvothermal reaction is selected from at least one of water, alcohols, ketones or pyridine solvents, preferably water;

Preferably, the molar ratio of potassium source, lithium source, transition metal source, oxalic acid source and water is (1-20): (1-40): (1-2): (2-20): (10-500) , Preferably (1-2): (1-4): (1-2): (2-5): (10-20).
The preparation method according to claim 4, characterized in that the potassium source is selected from at least one of potassium element, potassium oxide or potassium salt, preferably potassium salt;

And/or, the lithium source is selected from at least one of lithium element, lithium oxide, or lithium salt, preferably a lithium salt;

And/or, the source of the transition metal is at least one selected from the group consisting of a transition metal element, a transition metal oxide, or a transition metal salt; preferably a transition metal salt;

And/or, the oxalic acid source is selected from oxalic acid and/or oxalate, preferably oxalic acid.
Use of the crystalline material according to claim 1 or 2 or the crystalline material obtained by the preparation method according to any one of claims 3-5 in a battery positive electrode active material.
A positive electrode active material for a battery, characterized by comprising the crystalline material according to claim 1 or 2, or the crystalline material obtained by the preparation method according to any one of claims 3-5.
A battery positive electrode material, characterized by comprising the crystalline material according to claim 1 or 2, or the crystalline material obtained by the preparation method according to any one of claims 3-5;

Preferably, the battery cathode material includes a crystalline material, a cathode conductive agent, and a cathode binder;

Preferably, the battery cathode material includes crystalline material 60-90wt%, cathode conductive agent 5-30wt% and cathode binder 5-10wt%;

Preferably, the battery cathode material includes a lithium-deficient cathode active material, KLi 3 Tm(C 2 O 4 ) 3 , a cathode conductive agent, and a cathode binder;

Preferably, the battery cathode material includes lithium-deficient cathode active material 40-60wt%, KLi 3 Co(C 2 O 4 ) 3 10-30wt%, cathode conductive agent 5-30wt% and cathode binder 5-10wt% ;

Preferably, the lithium-deficient cathode active material is selected from CoPO 4 and/or CoSO 4 F.
A battery, characterized by comprising the crystalline material according to claim 1 or 2, the crystalline material obtained by the preparation method according to any one of claims 3-5, the battery positive electrode active material according to claim 7 or the right The battery positive electrode material according to claim 8;

Preferably, the battery is a potassium ion battery or a lithium ion battery.
An electric device, characterized by comprising the crystalline material according to claim 1 or 2, the crystalline material obtained by the preparation method according to any one of claims 3-5, and the battery positive electrode active material according to claim 7 7. The battery positive electrode material of claim 8 or the battery of claim 9.