WO2020124467A1 - Oxalate material, preparation method, use, lithium-ion battery cathode material and lithium-ion battery - Google Patents

Abstract

The present application relates to the technical field of batteries, and relates to an oxalate material, a preparation method, a use, a lithium-ion battery cathode material and a lithium-ion battery. The oxalate material of the present application comprises the following chemical compositions: Li2TMC4O8, wherein TM is a transition metal having charge of plus two. The oxalate material is a polyanionic-based cathode material having dual electrochemical activities and can be used as a lithium-ion battery cathode active material in a lithium-ion battery. With respect to existing lithium-ion battery cathode materials, the present application provides a designing and preparation method for a cathode material having a good safety and high capability. Besides, the synthesis method for the cathode active material is convenient, rapid and safe and all materials are cheap and easily obtained; and the cathode active material is important for optimizing battery material synthesis technique and reducing electrode material preparation cost.

Description

草酸盐材料、制备方法、用途、锂离子电池正极材料及锂离子电池Oxalate material, preparation method, use, cathode material of lithium ion battery and lithium ion battery 技术领域Technical field

本申请属于二次电池技术领域，具体而言，涉及一种草酸盐材料、制备方法、用途、锂离子电池正极材料及锂离子电池。The present application belongs to the technical field of secondary batteries, and specifically relates to an oxalate material, a preparation method, a use, a positive electrode material for a lithium ion battery, and a lithium ion battery.

背景技术Background technique

二次电池也可称为可充电电池，是一种可重复充放电、多次使用的电池。相比于不可重复使用的一次电池，二次电池具有使用成本低、对环境污染小的优点。目前，主要的二次电池技术包括铅酸电池、镍铬电池、镍氢电池、锂离子电池等。其中，锂离子电池的应用最为广泛，它是手机、笔记本电脑、数码相机等便携式电子设备的主要能源供给方式。锂离子电池的核心组成部件通常包含正极、负极和电解液，通过发生在正极、负极与电解液界面上的离子传输与电子传输相分离的氧化还原反应来实现电能存储与释放。传统锂离子电池的正极通常以过渡金属氧化物(LiCoO ₂、LiNi _xMn _yCo _1-x-yO ₂、LiMn ₂O ₄)组成。这些氧化物在充电过程中易发生骨架结构坍塌，并在高电压下(>4.3V)产气(氧气)，由此导致电池失效甚至***等危险，稳定性和安全性较差。 The secondary battery can also be called a rechargeable battery, which is a battery that can be repeatedly charged and discharged and used many times. Compared with non-reusable primary batteries, secondary batteries have the advantages of low use cost and low environmental pollution. At present, the main secondary battery technologies include lead-acid batteries, nickel-chromium batteries, nickel-metal hydride batteries, and lithium-ion batteries. Among them, lithium-ion batteries are the most widely used. It is the main energy supply method for portable electronic devices such as mobile phones, notebook computers, and digital cameras. The core components of a lithium-ion battery generally include a positive electrode, a negative electrode, and an electrolyte. The electrical energy is stored and released through a redox reaction that separates the ion transport and electron transport at the interface between the positive electrode, the negative electrode, and the electrolyte. The positive electrode of a conventional lithium ion battery is usually composed of transition metal oxides (LiCoO ₂ , LiNi _x Mn _y Co _1-xy O ₂ , LiMn ₂ O ₄ ). These oxides are prone to collapse of the skeleton structure during charging and produce gas (oxygen) at high voltage (>4.3V), which leads to the danger of battery failure or even explosion, and the stability and safety are poor.

目前，聚阴离子型正极材料因工作电压可调、稳定性和安全性高而广受关注，如磷酸亚铁锂(LiFePO ₄)、硫酸亚铁锂(Li ₂Fe(SO ₄) ₂)、硅酸亚铁锂(Li ₂FeSiO ₄)等，这些正极材料的稳定性优于现有的氧化物型正极材料，其电化学反应活性基于过渡金属的可变价态，例如，Fe ²⁺/Fe ³⁺氧化还原电对、Co ²⁺/Co ³⁺氧化还原电对、Mn ²⁺/Mn ³⁺氧化还原电对。然而，目前的聚阴离子型正极材料中的聚阴离子(酸根离子)作为非电化学活性成分，其引入增加了正极材料中的非活性质量，从而限制了正极材料及相应电池的容量和能量密度。因此，所期望的提供一种新型正极活性材料，能够克服当前的锂离子电池正极材料存在的电化学活性单一、非活性物质质量高的问题。 At present, polyanion cathode materials are widely concerned because of adjustable working voltage, high stability and safety, such as lithium iron phosphate (LiFePO ₄ ), lithium iron sulfate (Li ₂ Fe(SO ₄ ) ₂ ), silicon Lithium ferrous acid (Li ₂ FeSiO ₄ ), etc., the stability of these cathode materials is better than the existing oxide cathode materials, and their electrochemical reaction activity is based on the variable valence state of the transition metal, for example, Fe ²⁺ /Fe ^{3 +} Redox couple, Co ²⁺ /Co ³⁺ redox couple, Mn ²⁺ /Mn ³⁺ redox couple. However, the introduction of polyanions (acid ions) in current polyanion cathode materials as non-electrochemically active components increases their inactive mass in cathode materials, thereby limiting the capacity and energy density of cathode materials and corresponding batteries. Therefore, it is desirable to provide a new type of positive electrode active material, which can overcome the problems of single electrochemical activity and high quality of inactive materials existing in the current lithium ion battery positive electrode material.

鉴于此，特提出本申请。In view of this, this application is hereby submitted.

发明内容Summary of the invention

本申请的第一目的在于提供一种草酸盐材料，能够克服上述问题或者至少部分地解决上述技术问题。The first object of the present application is to provide an oxalate material that can overcome the above problems or at least partially solve the above technical problems.

本申请的第二目的在于提供一种上述草酸盐材料的制备方法，工艺简单、迅速、有效，成本低廉，环境友好。The second object of the present application is to provide a method for preparing the above oxalate material. The process is simple, rapid, effective, low cost, and environmentally friendly.

本申请的第三目的在于提供一种上述草酸盐材料作为锂离子电池电极活性材料的用途。The third object of the present application is to provide the use of the above oxalate material as an active material for an electrode of a lithium ion battery.

本申请的第四目的在于提供一种锂离子电池正极材料，包括上述草酸盐材料。The fourth object of the present application is to provide a positive electrode material for a lithium ion battery, including the above-mentioned oxalate material.

本申请的第五目的在于提供一种锂离子电池，包括上述的锂离子电池正极材料。本申请的第六目的在于提供一种包含上述锂离子电池的电子装置、电动工具、电动车辆或电力储存***。The fifth object of the present application is to provide a lithium ion battery, including the above-mentioned positive electrode material of the lithium ion battery. A sixth object of the present application is to provide an electronic device, power tool, electric vehicle, or power storage system including the above-mentioned lithium ion battery.

为实现上述目的，本申请采用的技术方案为：In order to achieve the above purpose, the technical solutions adopted in this application are:

根据本申请的一个方面，本申请提供一种草酸盐材料，所述草酸盐材料具有如下化学组成：Li ₂TMC ₄O ₈，其中，TM为正二价的过渡金属。 According to one aspect of the present application, the present application provides an oxalate material having the following chemical composition: Li ₂ TMC ₄ O ₈ , where TM is a positive divalent transition metal.

作为进一步优选技术方案，所述过渡金属包括Ti、V、Cr、Mn、Fe、Co、Ni、Cu和Zn中的至少一种，优选包括Fe、Mn、Co、Ni、Cu和Zn中的至少一种，进一步优选为Fe和/或Mn。As a further preferred technical solution, the transition metal includes at least one of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, and preferably includes at least one of Fe, Mn, Co, Ni, Cu, and Zn One is more preferably Fe and/or Mn.

作为进一步优选技术方案，所述草酸盐材料为异质同构体，具有三维结构，晶系属于单斜晶系，空间群为P2 ₁/n。 As a further preferred technical solution, the oxalate material is a heterogeneous isoform with a three-dimensional structure, the crystal system belongs to a monoclinic crystal system, and the space group is P2 ₁ /n.

作为进一步优选技术方案，所述草酸盐材料为草酸亚铁锂，分子式为Li ₂FeC ₄O ₈，属于单斜晶系，空间群为P2 ₁/n，分解温度为290～310℃，单胞参数为

α＝γ＝90°，β＝110.93(1)°，

Z＝4； As a further preferred technical solution, the oxalate material is lithium ferrous oxalate, the molecular formula is Li ₂ FeC ₄ O ₈ , which belongs to the monoclinic crystal system, the space group is P2 ₁ /n, and the decomposition temperature is 290-310°C. The cell parameters are

α=γ=90°, β=110.93(1)°,

Z=4;

和/或，所述草酸盐材料为草酸锰锂，分子式为Li ₂MnC ₄O ₈，属于单斜晶系，空间群为P2 ₁/n，分解温度为300～320℃，单胞参数为

α＝γ＝90°，β＝110.699(7)°，

Z＝4。 And/or, the oxalate material is lithium manganese oxalate, the molecular formula is Li ₂ MnC ₄ O ₈ , which belongs to the monoclinic crystal system, the space group is P2 ₁ /n, the decomposition temperature is 300～320℃, and the unit cell parameter is

α=γ=90°, β=110.699(7)°,

Z=4.

根据本申请的另一个方面，本申请提供一种上述草酸盐材料的制备方法，将锂源、过渡金属源和草酸源混合，进行溶剂热反应，得到所述草酸盐材料。According to another aspect of the present application, the present application provides a method for preparing the above oxalate material. A lithium source, a transition metal source and an oxalic acid source are mixed to perform a solvothermal reaction to obtain the oxalate material.

作为进一步优选技术方案，所述过渡金属源包括过渡金属钛源、过渡金属钒源、过渡金属铬源、过渡金属锰源、过渡金属铁源、过渡金属钴源、过渡金属镍源、过渡金属铜源和过渡金属锌源中的至少一种；As a further preferred technical solution, the transition metal source includes a transition metal titanium source, a transition metal vanadium source, a transition metal chromium source, a transition metal manganese source, a transition metal iron source, a transition metal cobalt source, a transition metal nickel source, a transition metal copper At least one of a source and a source of transition metal zinc;

优选地，所述过渡金属源包括过渡金属单质、过渡金属氧化物、过渡金属氢氧化物、过渡金属卤化物、过渡金属硫酸盐、过渡金属磷酸盐、过渡金属硝酸盐、过渡金属碳酸盐、过渡金属甲酸盐、过渡金属乙酸盐、过渡金属草酸盐、过渡金属铵盐、过渡金属酯化物及其水合物中的至少一种；Preferably, the transition metal source includes transition metal element, transition metal oxide, transition metal hydroxide, transition metal halide, transition metal sulfate, transition metal phosphate, transition metal nitrate, transition metal carbonate, At least one of transition metal formate, transition metal acetate, transition metal oxalate, transition metal ammonium salt, transition metal ester and its hydrate;

优选地，所述锂源包括碳酸锂、氢氧化锂、偏硼酸锂、钼酸锂、硫酸锂、四氟硼酸锂、磷酸锂、四氯铜酸锂、四硼酸锂、草酸锂、铬酸锂、三氟甲磺酸锂及其水合物中的至少一种；Preferably, the lithium source includes lithium carbonate, lithium hydroxide, lithium metaborate, lithium molybdate, lithium sulfate, lithium tetrafluoroborate, lithium phosphate, lithium tetrachlorocuprate, lithium tetraborate, lithium oxalate, lithium chromate , At least one of lithium trifluoromethanesulfonate and its hydrate;

优选地，所述草酸源包括草酸、草酸水合物、草酸盐和草酸盐水合物中的至少一种。Preferably, the oxalic acid source includes at least one of oxalic acid, oxalic acid hydrate, oxalate and oxalate hydrate.

作为进一步优选技术方案，过渡金属源、锂源、草酸源与溶剂的摩尔比为1：(1～20)：(8～40)：(3～400)，优选为1：(4～8)：(8～40)：(8～40)；As a further preferred technical solution, the molar ratio of the transition metal source, the lithium source, the oxalic acid source and the solvent is 1: (1-20): (8-40): (3-400), preferably 1: (4-8) : (8～40): (8～40);

优选地，溶剂热反应的温度为160～260℃，优选为180～250℃；Preferably, the temperature of the solvothermal reaction is 160-260°C, preferably 180-250°C;

和/或，溶剂热反应的时间为2～180小时，优选为4～168小时；And/or, the solvothermal reaction time is 2 to 180 hours, preferably 4 to 168 hours;

优选地，反应所用反应器的材质为聚四氟乙烯或者对位聚苯；Preferably, the material of the reactor used for the reaction is polytetrafluoroethylene or para-polyphenylene;

优选地，溶剂热反应之后还包括分离、洗涤和干燥的步骤；Preferably, the solvothermal reaction further includes steps of separation, washing and drying;

优选地，分离包括离心、超声、过滤和粒径分级中的至少一种；Preferably, the separation includes at least one of centrifugation, ultrasound, filtration and particle size classification;

优选地，干燥的温度为40～120℃，干燥的压力为≤20kPa，时间为10～24小时。Preferably, the drying temperature is 40 to 120° C., the drying pressure is ≤20 kPa, and the time is 10 to 24 hours.

根据本申请的另一个方面，本申请提供一种上述的草酸盐材料或利用上述的草酸盐材料的制备方法得到的草酸盐材料作为锂离子电池正极活性材料的用途。According to another aspect of the present application, the present application provides a use of the above-mentioned oxalate material or the oxalate material obtained by the above-mentioned preparation method of the oxalate material as a positive electrode active material of a lithium ion battery.

根据本申请的另一个方面，本申请提供一种锂离子电池正极材料，包括上述的草酸盐材料或利用上述的草酸盐材料的制备方法得到的草酸盐材料。According to another aspect of the present application, the present application provides a positive electrode material for a lithium ion battery, including the above-mentioned oxalate material or the oxalate material obtained by the above-mentioned preparation method of the oxalate material.

根据本申请的另一个方面，本申请提供一种锂离子电池，包括正极、负极、介于正极和负极之间的隔膜以及电解液；According to another aspect of the present application, the present application provides a lithium ion battery, including a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and an electrolyte;

其中，所述正极包括上述的锂离子电池正极材料以及正极集流体。Wherein, the positive electrode includes the foregoing positive electrode material of a lithium ion battery and a positive electrode current collector.

根据本申请的另一个方面，本申请提供一种包含所述的锂离子电池的电子装置、电动工具、电动车辆或电力储存***。According to another aspect of the present application, the present application provides an electronic device, a power tool, an electric vehicle, or a power storage system including the lithium-ion battery.

与现有技术相比，本申请的有益效果在于：Compared with the prior art, the beneficial effects of this application are:

1、本申请提供的草酸盐材料为具有双电化学活性的聚阴离子型正极活性材料，该材料的化学式为Li ₂TMC ₄O ₈，可以看出该正极活性材料所含的聚阴离子为草酸根离子，可作为电化学成分，即该材料所含的聚阴离子和过渡金属离子同时具有电化学氧化还原活性，相比于现有的正极材料，其反应机理新颖，有利于充分利用草酸根离子，降低正极材料中的非活性质量，提高电池的容量。 1. The oxalate material provided in this application is a polyanionic positive electrode active material with dual electrochemical activity. The chemical formula of the material is Li ₂ TMC ₄ O _8. It can be seen that the polyanion contained in the positive electrode active material is oxalic acid The root ion can be used as an electrochemical component, that is, the polyanion and transition metal ion contained in the material have electrochemical redox activity at the same time. Compared with the existing positive electrode material, the reaction mechanism is novel and it is beneficial to make full use of the oxalate ion , To reduce the inactive mass in the positive electrode material and increase the battery capacity.

2、本申请的新型化合物草酸盐正极活性材料，所用材料均储量丰富、价格低廉、易于获得，且均为环境友好的材料，对于降低二次电池的成本、提高二次电池的能量密度具有重要意义。从长远来看，所用草酸根可来自生物质降解或CO ₂转换，有利于充分利用有机自然资源并降低温室效应。 2. The new compound oxalate cathode active material of the present application, the materials used are all rich in reserves, low in price, easy to obtain, and are all environmentally friendly materials, which have the advantages of reducing the cost of secondary batteries and improving the energy density of secondary batteries. important meaning. In the long run, the oxalate used can come from biomass degradation or CO ₂ conversion, which is beneficial to make full use of organic natural resources and reduce the greenhouse effect.

3、相对于传统氧化物型锂离子电池正极活性材料，聚阴离子型正极活性材料的结构更加稳定，有利于提高电池的安全性和循环性能。3. Compared with the traditional oxide active material of lithium ion battery, the structure of polyanion positive electrode active material is more stable, which is conducive to improving the safety and cycle performance of the battery.

4、本申请所用合成工艺简洁、方便、迅速、有效，安全环保，所有材料均廉价易得，对于提高材料合成效率、优化电池材料的合成工艺、降低材料制备成本具有重要作用。4. The synthesis process used in this application is simple, convenient, rapid, effective, safe and environmentally friendly. All materials are cheap and readily available. It plays an important role in improving the synthesis efficiency of materials, optimizing the synthesis process of battery materials, and reducing the cost of material preparation.

5、上述新化合物草酸盐材料的用途为锂离子电池的正极材料，该锂离子电池正极包含上述聚阴离子化合物草酸盐材料、负极可为常规材料、电解液可为含有锂盐的有机溶液。所有材料均储量丰富、便宜易得，对于降低二次电池的价格具有重要作用。此外，该锂离 子电池组成材料均是环境友好型材料，不会造成环境污染。5. The use of the above-mentioned new compound oxalate material is a positive electrode material of a lithium-ion battery. The positive electrode of the lithium-ion battery contains the above-mentioned polyanionic compound oxalate material, the negative electrode may be a conventional material, and the electrolyte may be an organic solution containing a lithium salt . All materials are rich in reserves, cheap and readily available, and play an important role in reducing the price of secondary batteries. In addition, the lithium ion battery components are all environmentally friendly materials and will not cause environmental pollution.

附图说明BRIEF DESCRIPTION

为了更清楚地说明本申请具体实施方式或现有技术中的技术方案，下面将对具体实施方式或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图是本申请的一些实施方式，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。In order to more clearly explain the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the specific embodiments or the description of the prior art. Obviously, the appended The drawings are some embodiments of the present application. For those of ordinary skill in the art, without paying any creative work, other drawings can be obtained based on these drawings.

图1为本申请一种实施方式提供的正极活性材料Li ₂TMC ₄O ₈晶体结构示意图； 1 is a schematic diagram of a crystal structure of a positive electrode active material Li ₂ TMC ₄ O ₈ provided by an embodiment of the present application;

图2为本申请一种实施方式提供的正极活性材料Li ₂TMC ₄O ₈晶体形貌示意图； 2 is a schematic diagram of the crystal morphology of the positive electrode active material Li ₂ TMC ₄ O ₈ provided by an embodiment of the present application;

图3为本申请一种实施方式提供的正极活性材料Li ₂TMC ₄O ₈的X射线粉末衍射图(XRD图)； 3 is an X-ray powder diffraction pattern (XRD pattern) of a positive electrode active material Li ₂ TMC ₄ O ₈ provided by an embodiment of the present application;

图4为本申请一种实施方式提供的正极活性材料Li ₂TMC ₄O ₈热重分析图； 4 is a thermogravimetric analysis diagram of a positive electrode active material Li ₂ TMC ₄ O ₈ provided by an embodiment of the present application;

图5为本申请一种实施方式提供的包括正极活性材料Li ₂TMC ₄O ₈的锂离子电池示意图； 5 is a schematic diagram of a lithium ion battery including a positive electrode active material Li ₂ TMC ₄ O ₈ according to an embodiment of the present application;

图6为本申请一种实施方式提供的包括正极活性材料Li ₂TMC ₄O ₈的锂离子电池充放电曲线图。 6 is a charge-discharge curve diagram of a lithium ion battery including a positive electrode active material Li ₂ TMC ₄ O ₈ according to an embodiment of the present application.

图标：1-负极；2-电解液；3-隔膜；4-正极活性材料；5-正极集流体。Icons: 1-negative electrode; 2-electrolyte; 3-separator; 4-positive electrode active material; 5-positive electrode current collector.

具体实施方式detailed description

下面将结合实施方式和实施例对本申请的实施方案进行详细描述，但是本领域技术人员将会理解，下列实施方式和实施例仅用于说明本申请，而不应视为限制本申请的范围。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。未注明具体条件者，按照常规条件或制造商建议的条件进行。所用试剂或仪器未注明生产厂商者，均为可以通过市售购买获得的常规产品。The embodiments of the present application will be described in detail below in conjunction with the embodiments and examples, but those skilled in the art will understand that the following embodiments and examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts fall within the protection scope of the present application. If no specific conditions are indicated, follow the normal conditions or the conditions recommended by the manufacturer. The reagents or instruments used do not indicate the manufacturer, are all conventional products that can be obtained through commercial purchase.

需要说明的是：It should be noted:

本申请中，如果没有特别的说明，本文所提到的所有实施方式以及优选实施方法可以相互组合形成新的技术方案。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.

本申请中，如果没有特别的说明，本文所提到的所有技术特征以及优选特征可以相互组合形成新的技术方案。In this application, if there is no special description, all the technical features and preferred features mentioned in this document can be combined with each other to form a new technical solution.

本申请所公开的“范围”以下限和上限的形式，可以分别为一个或多个下限，和一个或多个上限。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.

本申请中，除非另有说明，各个反应或操作步骤可以顺序进行，也可以不按照顺序进行。优选地，本文中的方法是顺序进行的。In this application, unless otherwise stated, each reaction or operation step may be performed sequentially or not. Preferably, the methods herein are performed sequentially.

除非另有说明，本文中所用的专业与科学术语与本领域熟练人员所熟悉的意义相同。此外，任何与所记载内容相似或均等的方法或材料也可应用于本申请中。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.

第一方面，在至少一个实施例中提供一种草酸盐材料，所述草酸盐材料具有如下化学组成：Li ₂TMC ₄O ₈，其中，TM为正二价的过渡金属。 In a first aspect, in at least one embodiment, an oxalate material is provided, the oxalate material having the following chemical composition: Li ₂ TMC ₄ O ₈ , where TM is a positive divalent transition metal.

为缓解现有的氧化物型正极材料的结构稳定性较差，导致电池的安全性、循环性能较差的问题，和/或，现有的聚阴离子型正极材料电化学活性单一、非活质量高，导致电池的容量和能量密度较低的问题。本申请打破本领域技术人员常规思维的禁锢，独辟蹊径，创造性地提供一种新型有机聚阴离子化合物，将草酸根聚阴离子作为电化学活性成分，充分利用草酸根离子，降低正极材料中的非活性质量，提高电池的容量、能量密度，并且结构稳定，使得电池的安全性和循环性能优异。To alleviate the problem of poor structural stability of existing oxide-type cathode materials, resulting in poor battery safety and cycle performance, and/or, the existing polyanion-type cathode materials have single electrochemical activity and inactive mass High, leading to the problem of low battery capacity and energy density. This application breaks the confinement of the conventional thinking of those skilled in the art, opens up new ways, and creatively provides a new type of organic polyanion compound, which uses oxalate polyanion as an electrochemically active component, makes full use of oxalate ion, and reduces the inactive quality in the cathode material , Improve the capacity and energy density of the battery, and the structure is stable, making the battery excellent in safety and cycle performance.

上述草酸盐材料为双电化学活性的聚阴离子型正极活性材料，过渡金属离子和草酸根离子均具有电化学活性。The oxalate material is a dual-electrochemically active polyanionic positive electrode active material, and both the transition metal ion and the oxalate ion have electrochemical activity.

应当理解的是，本申请对于过渡金属TM的种类没有特殊限制，只要不对本申请的目的产生限制即可。It should be understood that there is no special restriction on the type of transition metal TM in this application, as long as the purpose of this application is not limited.

在一种优选的实施方式中，所述过渡金属包括Ti、V、Cr、Mn、Fe、Co、Ni、Cu和Zn中的至少一种；In a preferred embodiment, the transition metal includes at least one of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn;

优选地，所述过渡金属包括Fe、Mn、Co、Ni、Cu和Zn中的至少一种；更优选为Fe和/或Mn。Preferably, the transition metal includes at least one of Fe, Mn, Co, Ni, Cu, and Zn; more preferably Fe and/or Mn.

根据本申请，该草酸盐正极材料的化学式为Li ₂TMC ₄O ₈，其中TM为正二价的过渡金属，包括但不限于钛(Ti)、钒(V)、铬(Cr)、锰(Mn)、铁(Fe)、钴(Co)、镍(Ni)、铜(Cu)和锌(Zn)中的一种或多种的组合。例如，TM为Fe时，该化合物为草酸亚铁锂(Li ₂FeC ₄O ₈)简称LFO；TM为Mn时，该化合物为草酸锰(II)锂(Li ₂MnC ₄O ₈)简称LMO；当TM为混合过渡金属Fe和Mn时，该化合物可表示为Li ₂Fe _0.8Mn _0.2C ₄O ₈简称为L(Fe _0.8Mn _0.2)O，以此类推。 According to the present application, the chemical formula of the oxalate cathode material is Li ₂ TMC ₄ O ₈ , where TM is a positive divalent transition metal, including but not limited to titanium (Ti), vanadium (V), chromium (Cr), manganese ( A combination of one or more of Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), and zinc (Zn). For example, when TM is Fe, the compound is lithium ferrous oxalate (Li ₂ FeC ₄ O ₈ ) or LFO; when TM is Mn, the compound is lithium manganese (II) oxalate (Li ₂ MnC ₄ O ₈ ) or LMO; When TM is the mixed transition metals Fe and Mn, the compound can be expressed as Li ₂ Fe _0.8 Mn _0.2 C ₄ O ₈ referred to as L(Fe _0.8 Mn _0.2 )O, and so on.

应当理解的是，本申请对于混合过渡金属中的各组分的配比没有特殊限制，只要不对本申请的目的产生限制即可。例如，TM为混合过渡金属Fe和Mn时，Fe和Mn的比例可以为0.8:0.2，也可以为0.6:0.4，也可以为0.5:0.5；TM为混合过渡金属Fe、Co和Mn时，Fe、Co和Mn的比例可以为0.4:0.2:0.4，也可以为0.5:0.25：0.25等，本申请在此不再一一列举。It should be understood that the present application has no special restrictions on the ratio of each component in the mixed transition metal, as long as the purpose of the present application is not limited. For example, when TM is a mixed transition metal Fe and Mn, the ratio of Fe and Mn may be 0.8:0.2, or 0.6:0.4, or 0.5:0.5; when TM is a mixed transition metal Fe, Co, and Mn, Fe , The ratio of Co and Mn may be 0.4:0.2:0.4, or 0.5:0.25:0.25, etc., and this application will not list them one by one here.

在一种优选的实施方式中，所述草酸盐材料为异质同构体，具有三维结构，晶系属于单斜晶系，空间群为P2 ₁/n。进一步的，每两个碳原子和四个氧原子链接，形成C ₂O ₄草酸根基团；每个过渡金属原子与六个氧原子链接，这六个氧原子分别来自四个不同的草酸根；有两个氧原子只与碳原子链接而不与过渡金属原子相连，成为悬挂氧；每两个过渡金属-氧八面体共用一条边，形成[TM ₂O ₁₀]二聚体；该二聚体和草酸根共同形成三维骨架结构，Li 原子位于骨架结构的孔隙中。 In a preferred embodiment, the oxalate material is a heterogeneous isoform with a three-dimensional structure, the crystal system belongs to a monoclinic crystal system, and the space group is P2 ₁ /n. Further, every two carbon atoms and four oxygen atoms are linked to form a C ₂ O ₄ oxalate group; each transition metal atom is linked to six oxygen atoms, which are from four different oxalate groups; There are two oxygen atoms that are only linked to the carbon atom and not connected to the transition metal atom, and become a suspended oxygen; every two transition metal-oxygen octahedrons share an edge to form a [TM ₂ O ₁₀ ] dimer; the dimer Together with oxalate, a three-dimensional framework is formed, and Li atoms are located in the pores of the framework.

根据本申请，上述草酸盐材料为草酸根离子与过渡金属离子同时具有电化学氧化还原活性的聚阴离子型正极活性材料，是一种具有双电化学活性的聚阴离子型锂离子电池正极材料，能够克服现有锂离子电池正极材料电化学活性单一、非活性质量高的不足。进一步地讲，该正极活性材料具有三维结构，所含的聚阴离子和过渡金属离子同时具有电化学氧化还原活性。在电化学反应中，通过酸根离子变价和过渡金属离子变价实现锂离子的反复嵌入和脱出，从而实现电池的可逆充放电反应。According to the present application, the above oxalate material is a polyanionic positive electrode active material with electrochemical oxidation-reduction activity of both oxalate ions and transition metal ions, and is a polyanionic lithium ion battery cathode material with dual electrochemical activities. It can overcome the shortcomings of the existing lithium ion battery cathode material with single electrochemical activity and high inactive quality. Further, the positive electrode active material has a three-dimensional structure, and the contained polyanions and transition metal ions simultaneously have electrochemical redox activity. In the electrochemical reaction, the repetition of lithium ion insertion and extraction is achieved through the acid ion valence and transition metal ion valence, thereby achieving the reversible charge and discharge reaction of the battery.

实验表明，将本申请的正极活性材料应用在锂离子电池中，在2.0～4.5V的电压区间可实现50～300mAh/g的充放电容量。相对于现有锂离子电池正极材料来说，本申请提供了一种获得安全性好、比容量高的正极材料的设计及制备方法。Experiments show that the application of the positive electrode active material of the present application in a lithium ion battery can achieve a charge-discharge capacity of 50-300mAh/g in a voltage range of 2.0-4.5V. Compared with the existing cathode materials for lithium ion batteries, the present application provides a design and preparation method for obtaining anode materials with good safety and high specific capacity.

根据本申请，所提供的锂离子电池正极活性材料Li ₂TMC ₄O ₈，其中，TM为正二价的过渡金属Ti、V、Cr、Mn、Fe、Co、Ni、Cu或Zn中的一种或者多种的组合。该类化合物属于异质同构体，其结构均为单斜晶系，空间群为P2 ₁/n。其结构如图1所示：每两个C原子和四个氧原子链接，形成C ₂O ₄草酸根基团；每个过渡金属原子与六个氧原子链接，这六个氧原子分别来自四个不同的草酸根；有两个氧原子只与碳原子链接而不与过渡金属原子相连，成为悬挂氧；每两个过渡金属-氧八面体共用一条边，形成TM ₂O ₁₀二聚体；该二聚体和草酸根共同形成三维骨架结构，Li原子位于骨架结构的孔隙中。这种结构使得锂原子能够较容易的迁移，有利于获得高电化学活性和快速的反应动力学。Li ₂TMC ₄O ₈晶粒宏观呈棱柱状，如图2所示；其颜色依据过渡金属的种类不同而不同。经X射线粉末衍射(XRD)验证，样品晶粒为所述纯Li ₂TMC ₄O ₈化合物，如图3所示。 According to the present application, the provided lithium ion battery positive active material Li ₂ TMC ₄ O ₈ , where TM is one of the positive divalent transition metals Ti, V, Cr, Mn, Fe, Co, Ni, Cu or Zn Or a combination of multiple. These compounds belong to heterogeneous isomers, their structures are monoclinic and the space group is P2 ₁ /n. Its structure is shown in Figure 1: Every two C atoms and four oxygen atoms are linked to form a C ₂ O ₄ oxalate group; each transition metal atom is linked to six oxygen atoms, which are from four Different oxalates; there are two oxygen atoms that are only linked to carbon atoms and not connected to transition metal atoms to become dangling oxygen; every two transition metal-oxygen octahedrons share a side to form a TM ₂ O ₁₀ dimer; the The dimer and oxalate together form a three-dimensional skeleton structure, and Li atoms are located in the pores of the skeleton structure. This structure allows lithium atoms to migrate more easily, which is beneficial to obtain high electrochemical activity and fast reaction kinetics. The crystal grains of Li ₂ TMC ₄ O ₈ are prismatic, as shown in Fig. 2; their colors vary according to the type of transition metal. According to X-ray powder diffraction (XRD), the sample grains are the pure Li ₂ TMC ₄ O ₈ compounds, as shown in FIG. 3.

可以理解的是，图1中只是以Fe为示例，Fe的位置可以用过渡金属Ti、V、Cr、Mn、Co、Ni、Cu、Zn等中的部分或者全部取代。同样的，如图2中的Li ₂TMC ₄O ₈中TM包括正二价的过渡金属Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn中的一种或多种。如图3中的TM包括正二价的过渡金属Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn中的一种或多种，并伴随着角度的合理偏移。 It can be understood that FIG. 1 only uses Fe as an example, and the position of Fe may be partially or completely replaced with transition metals Ti, V, Cr, Mn, Co, Ni, Cu, Zn, and the like. Similarly, as in Li ₂ TMC ₄ O ₈ in FIG. 2, TM includes one or more of positive divalent transition metals Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn. As shown in FIG. 3, TM includes one or more of positive divalent transition metals Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, and is accompanied by a reasonable angle deviation.

该正极活性材料的分解温度一般在200～500℃范围内，如图4所示。可以理解的是，图4中只是以Fe为示例，Fe的位置可以用过渡金属Ti、V、Cr、Mn、Co、Ni、Cu、Zn等中的部分或者全部取代，并伴随着失重温度的合理偏移。The decomposition temperature of the positive electrode active material is generally in the range of 200 to 500°C, as shown in FIG. 4. It is understandable that Fe is only used as an example in FIG. 4, and the position of Fe can be partially or completely replaced with transition metals Ti, V, Cr, Mn, Co, Ni, Cu, Zn, etc., accompanied by the weightlessness temperature. Reasonable offset.

例如，草酸亚铁锂，分子式为Li ₂FeC ₄O ₈，浅黄色晶粒，属于单斜晶系，空间群为P2 ₁/n，分解温度约为300℃，在空气中不潮解，分子量为245.77，单胞参数为

α＝γ＝90°，β＝110.93(1)°,

Z＝4。 For example, lithium ferrous oxalate, with the molecular formula Li ₂ FeC ₄ O ₈ , light yellow grains, belongs to the monoclinic system, the space group is P2 ₁ /n, the decomposition temperature is about 300 ℃, it does not deliquesce in air, and the molecular weight is 245.77, the unit cell parameter is

α=γ=90°, β=110.93(1)°,

Z=4.

再例如，草酸锰锂，其分子式为Li ₂MnC ₄O ₈，淡粉色晶粒，属于单斜晶系，空间群为 P2 ₁/n，分解温度约为310℃，在空气中不潮解，分子量为244.86，单胞参数为

α＝γ＝90°，β＝110.699(7)°，

Z＝4。 As another example, lithium manganese oxalate, whose molecular formula is Li ₂ MnC ₄ O ₈ , pale pink grains, belongs to the monoclinic crystal system, the space group is P2 ₁ /n, the decomposition temperature is about 310℃, it does not deliquesce in the air, and its molecular weight Is 244.86, the unit cell parameter is

α=γ=90°, β=110.699(7)°,

Z=4.

第二方面，在至少一个实施例中提供一种上述草酸盐材料的制备方法，将锂源、过渡金属源和草酸源混合，进行溶剂热反应，得到所述草酸盐材料。In a second aspect, in at least one embodiment, a method for preparing the above oxalate material is provided. A lithium source, a transition metal source, and an oxalic acid source are mixed to perform a solvothermal reaction to obtain the oxalate material.

本申请的合成方法方便、快捷、安全，所有材料均廉价易得，对于优化电池材料的合成工艺、降低电极材料的制作成本具有重要作用。从长远来看，所用草酸根可来自生物质降解或者CO ₂转换，有利于充分利用有机自然资源并降低温室效应。此外，将上述草酸盐材料应用在锂离子电池中，所提供的锂离子二次电池，均采用储量丰富、价格低廉、易于获得、且环境友好的材料，对于降低二次电池的成本、提高二次电池的能量密度具有重要意义。 The synthesis method of the present application is convenient, fast, and safe, and all materials are cheap and readily available, which plays an important role in optimizing the synthesis process of battery materials and reducing the production cost of electrode materials. In the long run, the oxalate used can come from biomass degradation or CO ₂ conversion, which is beneficial to make full use of organic natural resources and reduce the greenhouse effect. In addition, the above oxalate materials are used in lithium-ion batteries. The lithium-ion secondary batteries provided are made of materials with abundant reserves, low prices, easy access, and environmental friendliness. The energy density of the secondary battery is of great significance.

在一种优选的实施方式中，所述方法包括以下步骤：In a preferred embodiment, the method includes the following steps:

(a)按照一定比例称量锂源、过渡金属源和草酸源，将称量的原料搅拌混合均匀，加入一定量的溶剂混合，得到混合液；(a) Weigh the lithium source, transition metal source and oxalic acid source according to a certain ratio, mix the weighed raw materials evenly, add a certain amount of solvent and mix to obtain a mixed solution;

(b)将所述混合液在反应器中恒温加热，冷却降温后得到反应混合物，即得到正极活性材料与反应副产物；以及(b) heating the mixed solution at a constant temperature in the reactor, cooling and lowering the temperature to obtain a reaction mixture, that is, a cathode active material and reaction by-products; and

(c)将所述反应混合物中的沉淀分离出来，经洗涤和真空干燥后，得到所述草酸盐材料。(c) The precipitate in the reaction mixture is separated, washed and dried in vacuum to obtain the oxalate material.

需要说明的是，本申请对于所用原料锂源、过渡金属源、草酸源等的来源没有特殊的限制，采用本领域技术人员所熟知的各原料即可；如可以采用其市售商品，也可以采用本领域技术人员熟知的制备方法自行制备。It should be noted that the present application has no special restrictions on the sources of the raw material lithium source, transition metal source, oxalic acid source, etc., and all raw materials well known to those skilled in the art may be used; It is prepared by the preparation method well known to those skilled in the art.

较佳的，步骤(a)中，过渡金属源包括但不限于过渡金属钛源、过渡金属钒源、过渡金属铬源、过渡金属锰源、过渡金属铁源、过渡金属钴源、过渡金属镍源、过渡金属铜源和过渡金属锌源中的一种或多种；Preferably, in step (a), the transition metal source includes, but is not limited to, a transition metal titanium source, a transition metal vanadium source, a transition metal chromium source, a transition metal manganese source, a transition metal iron source, a transition metal cobalt source, a transition metal nickel One or more of source, transition metal copper source and transition metal zinc source;

进一步的，过渡金属源包括但不限于过渡金属单质、过渡金属氧化物、过渡金属氢氧化物、过渡金属卤化物、过渡金属硫酸盐、过渡金属磷酸盐、过渡金属硝酸盐、过渡金属碳酸盐、过渡金属甲酸盐、过渡金属乙酸盐、过渡金属草酸盐、过渡金属铵盐、过渡金属酯化物及其水合物中的至少一种。Further, transition metal sources include, but are not limited to, transition metal elements, transition metal oxides, transition metal hydroxides, transition metal halides, transition metal sulfates, transition metal phosphates, transition metal nitrates, and transition metal carbonates , At least one of transition metal formate, transition metal acetate, transition metal oxalate, transition metal ammonium salt, transition metal ester and its hydrate.

应当理解的是，本申请对于过渡金属源的种类没有特殊限制，只要不对本申请的目的产生限制即可。It should be understood that this application has no special restrictions on the type of transition metal source, as long as it does not limit the purpose of this application.

优选地，过渡金属钛源包括单质钛、三氧化二钛、二氧化钛、硫酸钛(Ⅲ)、硫酸钛(Ⅳ)、磷酸钛、氟钛酸钾、六氟钛酸、钛酸四丁酯、钛酸四乙酯、钛酸异丙酯、四氯化钛、三氯化钛、二氢化钛、氟钛酸铵、四氟化钛、二氯二茂钛、双(乙酰丙酮基)异丙基钛酸酯及 其水合物中的一种或多种。更优选地，过渡金属钛源为四氟化钛、硫酸钛(Ⅲ)、三氯化钛及其水合物。Preferably, the transition metal titanium source includes elemental titanium, titanium dioxide, titanium dioxide, titanium (III) sulfate, titanium (IV) sulfate, titanium phosphate, potassium fluorotitanate, hexafluorotitanic acid, tetrabutyl titanate, titanium Tetraethyl acid, isopropyl titanate, titanium tetrachloride, titanium trichloride, titanium dihydride, ammonium fluorotitanate, titanium tetrafluoride, titanium dichloride, bis(acetylacetonyl)isopropyl One or more of titanate and its hydrate. More preferably, the source of the transition metal titanium is titanium tetrafluoride, titanium (III) sulfate, titanium trichloride, and hydrates thereof.

优选地，过渡金属钒源包括单质钒、三氧化二钒、二氧化钒、五氧化二钒、二氟化钒、三氟化钒、四氟化钒、五氟化钒、氟氧化钒、二氯化钒、三氯化钒、四氯化钒、氯氧化钒、二溴化钒、三溴化钒、四溴化钒、偏钒酸铵、正钒酸钾、偏钒酸钾、乙酰丙酮钒、乙酰丙酮氧钒、三异丙氧基氧化钒、三丙醇氧化钒及其水合物中的一种或多种。更优选地，过渡金属钒源为二氧化钒、五氧化二钒、氟氧化钒及其水合物。Preferably, the source of the transition metal vanadium includes elemental vanadium, vanadium trioxide, vanadium dioxide, vanadium pentoxide, vanadium difluoride, vanadium trifluoride, vanadium tetrafluoride, vanadium pentafluoride, vanadium oxyfluoride, divalent Vanadium chloride, vanadium trichloride, vanadium tetrachloride, vanadium oxychloride, vanadium dibromide, vanadium tribromide, vanadium tetrabromide, ammonium metavanadate, potassium orthovanadate, potassium metavanadate, acetylacetone One or more of vanadium, vanadium acetylacetonate, vanadium triisopropoxide, vanadium tripropoxide and their hydrates. More preferably, the source of the transition metal vanadium is vanadium dioxide, vanadium pentoxide, vanadium oxyfluoride, and hydrates thereof.

优选地，过渡金属铬源包括单质铬、三氧化铬、二氧化铬、三氧化二铬、氢氧化铬、硫酸铬、硫酸亚铬、亚铬酸锂、重铬酸钾、重铬酸钠、铬钒、三氟化铬、二氯化铬、三氯化铬、溴化铬、溴化亚铬、正磷酸铬、偏磷酸铬、焦磷酸铬、酸式磷酸铬、碱式磷酸铬、磷氯酸铬、硝酸铬、硝酸亚铬、甲酸铬、乙酸镉、乙酸亚铬、草酸铬及其水合物中的一种或多种。更优选地，过渡金属铬源为氢氧化铬、二氯化铬、三氯化铬及其水合物。Preferably, the transition metal chromium source includes elemental chromium, chromium trioxide, chromium dioxide, chromium trioxide, chromium hydroxide, chromium sulfate, chromite sulfate, lithium chromite, potassium dichromate, sodium dichromate, Chromium vanadium, chromium trifluoride, chromium dichloride, chromium trichloride, chromium bromide, chromium bromide, chromium orthophosphate, chromium metaphosphate, chromium pyrophosphate, acid chromium phosphate, basic chromium phosphate, phosphorus One or more of chromium chlorate, chromium nitrate, chromium nitrate, chromium formate, cadmium acetate, chromium acetate, chromium oxalate and their hydrates. More preferably, the source of transition metal chromium is chromium hydroxide, chromium dichloride, chromium trichloride and their hydrates.

优选地，过渡金属锰源包括单质锰、氧化锰、二氧化锰、四氧化三锰、氟化锰(Ⅱ)、氟化锰(Ⅲ)、氯化锰(Ⅱ)、氯化锰(Ⅲ)、溴化锰、碳酸锰、硝酸锰、硫酸锰、磷酸锰、磷酸二氢锰、乙酰丙酮锰、甲酸锰、乙酸锰(Ⅱ)、乙酸锰(Ⅲ)、草酸锰及其水合物中的一种或多种。更优选地，过渡金属锰源为乙酸锰、草酸锰、氯化锰及其水合物。Preferably, the source of transition metal manganese includes elemental manganese, manganese oxide, manganese dioxide, trimanganese tetraoxide, manganese (II) fluoride, manganese fluoride (Ⅲ), manganese chloride (Ⅱ), manganese chloride (Ⅲ) , Manganese bromide, manganese carbonate, manganese nitrate, manganese sulfate, manganese phosphate, manganese dihydrogen phosphate, manganese acetylacetonate, manganese formate, manganese acetate (Ⅱ), manganese acetate (Ⅲ), manganese oxalate and one of its hydrates One or more. More preferably, the source of transition metal manganese is manganese acetate, manganese oxalate, manganese chloride and hydrates thereof.

优选地，过渡金属铁源包括单质铁、三氧化二铁、四氧化三铁、氢氧化亚铁、氢氧化铁、氟化亚铁、氟化铁、氯化亚铁、氯化铁、溴化亚铁、溴化铁、甲酸铁、乙酸亚铁、硝酸亚铁、硫酸亚铁、硝酸铁、硫酸铁、乙酰丙酮铁、草酸亚铁、草酸铁及其水合物中的一种或者多种。更优选地，过渡金属铁源为草酸亚铁、氯化亚铁及其水合物。Preferably, the transition metal iron source includes elemental iron, ferric oxide, ferric oxide, ferrous hydroxide, ferric hydroxide, ferrous fluoride, ferric fluoride, ferrous chloride, ferric chloride, bromide One or more of ferrous iron, ferric bromide, ferric formate, ferrous acetate, ferrous nitrate, ferrous sulfate, ferric nitrate, ferric sulfate, ferric acetylacetonate, ferrous oxalate, ferric oxalate and their hydrates. More preferably, the source of transition metal iron is ferrous oxalate, ferrous chloride, and hydrates thereof.

优选地，过渡金属钴源包括单质钴、一氧化钴、三氧化二钴、四氧化三钴、氢氧化钴(Ⅱ)、氢氧化钴(Ⅲ)、氟化钴(Ⅱ)、氟化钴(Ⅲ)、氯化钴(Ⅱ)、氯化钴(Ⅲ)、溴化钴、硝酸钴、硫酸钴、碳酸钴、乙酸钴、草酸钴、六氨基氯化钴、乙酰丙酮钴及其水合物中的一种或多种。更优选地，过渡金属钴源为乙酸钴、草酸钴、氯化钴及其水合物。Preferably, the source of the transition metal cobalt includes elemental cobalt, cobalt monoxide, cobalt trioxide, tricobalt tetroxide, cobalt (II) hydroxide, cobalt hydroxide (Ⅲ), cobalt fluoride (II), cobalt fluoride (Ⅲ), Cobalt(Ⅱ) chloride, cobalt(Ⅲ) chloride, cobalt bromide, cobalt nitrate, cobalt sulfate, cobalt carbonate, cobalt acetate, cobalt oxalate, hexaaminocobalt chloride, cobalt acetylacetonate and one of its hydrates Or more. More preferably, the source of the transition metal cobalt is cobalt acetate, cobalt oxalate, cobalt chloride, and hydrates thereof.

优选地，过渡金属镍源包括单质镍、氧化镍、氧化高镍、氢氧化镍、氢氧化高镍、氟化镍、氯化镍、溴化镍、硝酸镍、碳酸镍、硫酸镍、乙酸镍、草酸镍、双(六氟乙基丙酮)合镍、氨基磺酸镍、碱式碳酸镍、乙酰丙酮镍二水合物、三氟甲磺酸镍、苯磺酸镍、乙酰丙酮镍、氟硼酸镍中的一种或多种。更优选地，过渡金属镍源为草酸镍、氯化镍、氟化镍、乙酸镍及其水合物。Preferably, the transition metal nickel source includes elemental nickel, nickel oxide, high nickel oxide, nickel hydroxide, high nickel hydroxide, nickel fluoride, nickel chloride, nickel bromide, nickel nitrate, nickel carbonate, nickel sulfate, nickel acetate , Nickel oxalate, nickel bis(hexafluoroethylacetone), nickel sulfamate, basic nickel carbonate, nickel acetylacetonate dihydrate, nickel trifluoromethanesulfonate, nickel benzenesulfonate, nickel acetylacetonate, fluoroboric acid One or more of nickel. More preferably, the source of transition metal nickel is nickel oxalate, nickel chloride, nickel fluoride, nickel acetate, and hydrates thereof.

优选地，过渡金属铜源包括单质铜、氧化亚铜、氧化铜、氢氧化铜、氟化铜、氯化铜、溴化铜、碳酸铜、碱式碳酸铜、硝酸铜、硫酸铜、乙酸铜、草酸铜、酒石酸铜、柠檬酸铜、氟硼酸铜、乙酰丙酮铜、葡萄糖酸铜及其水合物中的一种或多种。更优选地，过渡金属铜 源为醋酸铜、硫酸铜、氯化铜及其水合物。Preferably, the transition metal copper source includes elemental copper, cuprous oxide, copper oxide, copper hydroxide, copper fluoride, copper chloride, copper bromide, copper carbonate, basic copper carbonate, copper nitrate, copper sulfate, copper acetate , Copper oxalate, copper tartrate, copper citrate, copper fluoroborate, copper acetylacetonate, copper gluconate and one or more of their hydrates. More preferably, the source of the transition metal copper is copper acetate, copper sulfate, copper chloride, and hydrates thereof.

优选地，过渡金属锌源包括单质锌、氧化锌、氢氧化锌、氟化锌、氯化锌、溴化锌、碘化锌、硫酸锌、硝酸锌、碳酸锌、乙酸锌、草酸锌、柠檬酸锌、氟硼酸锌、酒石酸锌、硼酸锌、偏硼酸锌、乙酰丙酮锌、葡萄糖酸锌及其水合物中的一种或多种。更优选地，过渡金属锌源为硫酸锌、氯化锌及其水合物。Preferably, the transition metal zinc source includes elemental zinc, zinc oxide, zinc hydroxide, zinc fluoride, zinc chloride, zinc bromide, zinc iodide, zinc sulfate, zinc nitrate, zinc carbonate, zinc acetate, zinc oxalate, lemon One or more of zinc acid, zinc fluoroborate, zinc tartrate, zinc borate, zinc metaborate, zinc acetylacetonate, zinc gluconate and their hydrates. More preferably, the source of transition metal zinc is zinc sulfate, zinc chloride, and hydrates thereof.

应当理解的是，本申请对于锂源的种类没有特殊限制，只要能使混合溶液中含有锂离子，且不对本申请的目的产生限制即可。It should be understood that the present application has no particular limitation on the type of lithium source, as long as the mixed solution can contain lithium ions without limiting the purpose of the present application.

优选地，锂源包括但不限于碳酸锂(Li ₂CO ₃)、氢氧化锂(LiOH)、偏硼酸锂(LiBO ₂)、钼酸锂(Li ₂MoO ₄)、硫酸锂(Li ₂SO ₄)、四氟硼酸锂(LiBF ₄)、磷酸锂(Li ₃PO ₄)、四氯铜酸锂(Li ₂CuCl ₄)、四硼酸锂(Li ₂B ₄O ₇)、草酸锂(Li ₂C ₂O ₄)、铬酸锂(Li ₂CrO ₄)、三氟甲磺酸锂(CF ₃SO ₃Li)及上述物质的水合物中的任意一种或至少两种的组合。更优选地，锂源为碳酸锂(Li ₂CO ₃)。 Preferably, the lithium source includes but is not limited to lithium carbonate (Li ₂ CO ₃ ), lithium hydroxide (LiOH), lithium metaborate (LiBO ₂ ), lithium molybdate (Li ₂ MoO ₄ ), lithium sulfate (Li ₂ SO ₄ ), lithium tetrafluoroborate (LiBF ₄ ), lithium phosphate (Li ₃ PO ₄ ), lithium tetrachlorocuprate (Li ₂ CuCl ₄ ), lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium oxalate (Li ₂ C ₂ O ₄ ), lithium chromate (Li ₂ CrO ₄ ), lithium trifluoromethanesulfonate (CF ₃ SO ₃ Li), and any one or a combination of at least two of the hydrates of the foregoing. More preferably, the lithium source is lithium carbonate (Li ₂ CO ₃ ).

应当理解的是，本申请对于草酸源的种类没有特殊限制，只要不对本申请的目的产生限制即可。It should be understood that there is no special restriction on the type of oxalic acid source in this application, as long as it does not limit the purpose of this application.

优选地，草酸源包括但不限于草酸、草酸水合物、草酸盐和草酸盐水合物中的一种或多种的组合。更优选地，草酸源为草酸水合物。Preferably, the oxalic acid source includes, but is not limited to, a combination of one or more of oxalic acid, oxalic acid hydrate, oxalate, and oxalate hydrate. More preferably, the source of oxalic acid is oxalic acid hydrate.

应当理解的是，本申请对于溶剂的种类没有特殊限制，只要不对本申请的目的产生限制即可。It should be understood that there is no special restriction on the type of solvent in this application, as long as the purpose of this application is not limited.

优选地，溶剂包括但不限于水、醇类溶剂、酮类溶剂等，更优选地，所述溶剂为水。Preferably, the solvent includes but is not limited to water, alcohol solvents, ketone solvents, etc. More preferably, the solvent is water.

需要说明的是，本申请中的反应溶剂优选采用的是水，水可以来源于含有水的原料，例如草酸水合物或草酸盐水合物，也可以在反应中额外添加一定量的水。It should be noted that the reaction solvent in the present application is preferably water. Water may be derived from raw materials containing water, such as oxalic acid hydrate or oxalate hydrate, or a certain amount of water may be added to the reaction.

根据本申请，步骤(a)中，过渡金属源、锂源、草酸源与溶剂的摩尔比为1：(1～20)：(8～40)：(3～400)，优选为1：(4～8)：(8～40)：(8～40)；典型但非限制的，例如可以为1:2:8:4、1:4:8:8、1:5:10:15、1:6:10:20、1:7:30:30或1:8:40:40。适宜的原料比制得的正极活性材料的综合性能好，能更好的发挥正极活性材料在该体系电池中的作用。According to the present application, in step (a), the molar ratio of the transition metal source, the lithium source, the oxalic acid source and the solvent is 1: (1-20): (8-40): (3-400), preferably 1: 4～8): (8～40): (8～40); typical but not limited, for example, 1:2:8:4, 1:4:8:8, 1:5:10:15, 1:6:10:20, 1:7:30:30 or 1:8:40:40. The suitable raw materials have better overall performance than the prepared cathode active material, and can better play the role of the cathode active material in the system battery.

根据本申请，步骤(b)中，恒温加热的温度为160～260℃，优选为180～250℃；典型但非限制的，例如可以为160℃、180℃、200℃、220℃、240℃、250℃或260℃。恒温加热的时间为2～180小时，优选为4～168小时；典型但非限制的，例如可以为2小时、4小时、6小时、8小时、10小时、12小时、24小时、36小时、48小时、96小时、168小时等。适宜的反应温度和反应时间可以使各原料更充分的反应，提高反应速率，制得的正极活性材料的电化学性能更优异。According to the present application, in step (b), the temperature of constant temperature heating is 160-260°C, preferably 180-250°C; typical but not limited, for example, 160°C, 180°C, 200°C, 220°C, 240°C , 250℃ or 260℃. The time of constant temperature heating is 2 to 180 hours, preferably 4 to 168 hours; typical but not limited, for example, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 36 hours, 48 hours, 96 hours, 168 hours, etc. Appropriate reaction temperature and reaction time can make each raw material react more fully, increase the reaction rate, and the cathode active material obtained has more excellent electrochemical performance.

步骤(b)中，冷却的时间或降温所需时间为2～48小时，优选为2～24小时；典型但 非限制的，例如可以为2小时、4小时、6小时、8小时、10小时、12小时、24小时或48小时等。In step (b), the cooling time or the time required to lower the temperature is 2 to 48 hours, preferably 2 to 24 hours; typical but not limited, for example, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours , 12 hours, 24 hours, or 48 hours.

步骤(b)中，反应器为密封的聚四氟乙烯或者对位聚苯材质。采用这两种材质的反应器进行反应，可以实现耐酸碱腐蚀、耐高温、密封性好、高润滑、不粘附、允许骤冷骤热、和无毒害，对所述反应不产生任何有害副作用。In step (b), the reactor is made of sealed polytetrafluoroethylene or para-polyphenylene. Reacting with these two material reactors, it can achieve acid and alkali corrosion resistance, high temperature resistance, good sealing, high lubrication, non-adhesion, allow quenching and sudden heat, and non-toxic, without any harm to the reaction side effect.

根据本申请，步骤(c)中，分离包括离心、超声、过滤和粒径分级中的至少一种。应当理解的是，本申请对于分离的方式没有特殊的限制，采用本领域技术人员所熟知的分离方式即可；例如通过离心、超声、抽滤、粒径分级方式等将反应生成的沉淀分离出来。According to the present application, in step (c), the separation includes at least one of centrifugation, ultrasound, filtration, and particle size classification. It should be understood that there is no particular limitation on the separation method in this application, and the separation method well known to those skilled in the art may be used; for example, the precipitate generated by the reaction is separated by centrifugation, ultrasound, suction filtration, particle size classification, etc. .

需要说明的是，本申请对于步骤(c)中的洗涤方式没有特殊的限制，采用本领域技术人员所熟知的洗涤方式即可；例如可以将分离出来的沉淀用水或乙醇进行洗涤。It should be noted that the present application has no particular limitation on the washing method in step (c), and it may be a washing method well known to those skilled in the art; for example, the separated precipitate can be washed with water or ethanol.

步骤(c)中，干燥的温度为40～120℃，干燥的压力为≤20kPa，时间为10～24小时。In step (c), the drying temperature is 40 to 120° C., the drying pressure is ≤20 kPa, and the time is 10 to 24 hours.

第三方面，在至少一个实施例中提供一种上述草酸盐材料作为锂离子电池正极活性材料的用途。In a third aspect, in at least one embodiment, there is provided a use of the above oxalate material as a positive electrode active material for a lithium ion battery.

第四方面，在至少一个实施例中提供一种锂离子电池正极材料，包括上述的草酸盐材料。According to a fourth aspect, in at least one embodiment, a positive electrode material for a lithium ion battery is provided, including the oxalate material described above.

第五方面，在至少一个实施例中提供一种锂离子电池，包括正极、负极、介于正极和负极之间的隔膜以及电解液；According to a fifth aspect, in at least one embodiment, a lithium ion battery is provided, including a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and an electrolyte;

其中，所述正极包括上述的草酸盐材料(正极活性材料)以及正极集流体。Wherein, the positive electrode includes the above-mentioned oxalate material (positive electrode active material) and a positive electrode current collector.

可以理解的是，本申请对于锂离子二次电池的除正极活性材料以外的其余部件不做特殊限制，该锂离子二次电池的核心在于包含了本申请的正极活性材料，其余组成或部件可参照现有技术。It can be understood that the present application does not specifically limit the remaining components of the lithium ion secondary battery except the positive electrode active material. The core of the lithium ion secondary battery is that the positive electrode active material of the present application is included, and the remaining components or components can be Refer to existing technology.

参照图5所示，包含本申请的正极活性材料Li ₂TMC ₄O ₈的锂离子电池的基本构造，包括：负极(1)、电解液(2)、隔膜(3)正极活性材料(4)、正极集流体(5)以及用于封装的电池壳体，其中的负极(1)包括电池负极活性材料和负极集流体。 As shown in FIG. 5, the basic structure of a lithium ion battery including the positive electrode active material Li ₂ TMC ₄ O ₈ of the present application includes: a negative electrode (1), an electrolyte (2), a separator (3), and a positive electrode active material (4) , A cathode current collector (5) and a battery case for packaging, wherein the anode (1) includes a battery anode active material and an anode current collector.

可选的，当负极活性材料使用金属箔材时，则不需要负极集流体；电解液为钾盐电解质和有机溶剂及添加剂的混合溶液；电池正极活性材料为以上所述的正极活性材料。Optionally, when a metal foil is used as the negative electrode active material, the negative electrode current collector is not required; the electrolyte is a mixed solution of potassium salt electrolyte and organic solvent and additives; and the battery positive electrode active material is the positive electrode active material described above.

优选地，负极活性材料包括碳材料、金属氧化物、硫化物、硒化物、碲化物、金属及其合金中的一种或多种。Preferably, the negative electrode active material includes one or more of carbon materials, metal oxides, sulfides, selenides, tellurides, metals, and alloys thereof.

优选地，负极集流体包括铝、铜、铁、锡、锌、镍、钛、锰中的一种或前述的合金或前述的复合材料。Preferably, the negative electrode current collector includes one of aluminum, copper, iron, tin, zinc, nickel, titanium, and manganese, or the aforementioned alloy or the aforementioned composite material.

优选地，正极集流体包括铝、铜、铁、锡、锌、镍、钛、锰中的一种或前述的合金或前述的复合材料。Preferably, the positive electrode current collector includes one of aluminum, copper, iron, tin, zinc, nickel, titanium, and manganese or the aforementioned alloy or the aforementioned composite material.

进一步优选地，负极集流体为铝，正极集流体为铝。Further preferably, the negative electrode current collector is aluminum, and the positive electrode current collector is aluminum.

本申请对于电解液中的溶剂没有特别限制，只要溶剂可以使电解质离解成阳离子和阴离子，且阳离子和阴离子可以自由迁移即可。例如，本申请实施例电解液中的溶剂包括酯类、砜类、醚类、腈类或离子液体等有机溶剂。具体地，包括碳酸丙烯酯(PC)、碳酸乙烯酯(EC)、碳酸二乙酯(DEC)、碳酸二甲酯(DMC)、碳酸甲乙酯(EMC)、甲酸甲酯(MF)、乙酸甲酯(MA)、N,N-二甲基乙酰胺(DMA)、氟代碳酸乙烯酯(FEC)、丙酸甲酯(MP)、丙酸乙酯(EP)、乙酸乙酯(EA)、γ-丁内酯(GBL)、四氢呋喃(THF)、2-甲基四氢呋喃(2MeTHF)、1,3-二氧环戊烷(DOL)、4-甲基-1,3-二氧环戊烷(4MeDOL)、二甲氧甲烷(DMM)、1,2-二甲氧丙烷(DMP)、三乙二醇二甲醚(DG)、二甲基砜(MSM)、二甲醚(DME)、亚硫酸乙烯酯(ES)、亚硫酸丙烯脂(PS)、亚硫酸二甲脂(DMS)、亚硫酸二乙脂(DES)、冠醚(12-冠-4)、1-乙基-3-甲基咪唑-六氟磷酸盐、1-乙基-3-甲基咪唑-四氟硼酸盐、1-乙基-3-甲基咪唑-双三氟甲基磺酰亚胺盐、1-丙基-3-甲基咪唑-六氟磷酸盐、1-丙基-3-甲基咪唑-四氟硼酸盐、1-丙基-3-甲基咪唑-双三氟甲基磺酰亚胺盐、1-丁基-1-甲基咪唑-六氟磷酸盐、1-丁基-1-甲基咪唑-四氟硼酸盐、1-丁基-1-甲基咪唑-双三氟甲基磺酰亚胺盐、N-丁基-N-甲基吡咯烷-双三氟甲基磺酰亚胺盐、1-丁基-1-甲基吡咯烷-双三氟甲基磺酰亚胺盐、N-甲基-N-丙基吡咯烷-双三氟甲基磺酰亚胺盐、N-甲,丙基哌啶-双三氟甲基磺酰亚胺盐、以及N-甲,丁基哌啶-双三氟甲基磺酰亚胺盐中的一种或几种。The present application has no particular limitation on the solvent in the electrolyte, as long as the solvent can dissociate the electrolyte into cations and anions, and the cations and anions can freely migrate. For example, the solvents in the electrolyte in the embodiments of the present application include organic solvents such as esters, sulfones, ethers, nitriles, or ionic liquids. Specifically, including propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), methyl formate (MF), acetic acid Methyl ester (MA), N,N-dimethylacetamide (DMA), fluoroethylene carbonate (FEC), methyl propionate (MP), ethyl propionate (EP), ethyl acetate (EA) , Γ-butyrolactone (GBL), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2MeTHF), 1,3-dioxolane (DOL), 4-methyl-1,3-dioxolane Alkane (4MeDOL), dimethoxymethane (DMM), 1,2-dimethoxypropane (DMP), triethylene glycol dimethyl ether (DG), dimethyl 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-methylimidazole-bistrifluoromethylsulfonimide salt, 1-propyl-3-methylimidazole-hexafluorophosphate, 1-propyl-3-methylimidazole-tetrafluoroborate, 1-propyl-3-methylimidazole-bistrifluoromethylsulfonate Imide salt, 1-butyl-1-methylimidazole-hexafluorophosphate, 1-butyl-1-methylimidazole-tetrafluoroborate, 1-butyl-1-methylimidazole-bis Trifluoromethylsulfonimide salt, N-butyl-N-methylpyrrolidine-bistrifluoromethylsulfonimide salt, 1-butyl-1-methylpyrrolidine-bistrifluoromethyl Sulfonimide salt, N-methyl-N-propylpyrrolidine-bistrifluoromethylsulfonimide salt, N-methyl, propylpiperidine-bistrifluoromethylsulfonimide salt, and One or more of N-methyl, butyl piperidine-bis-trifluoromethylsulfonimide salt.

本申请对于作为电解质的锂盐也没有特别限制，只要可以离解成阳离子和阴离子即可。例如可以包括六氟磷酸锂、氯化锂、氟化锂、硫酸锂、碳酸锂、磷酸锂、硝酸锂、二氟草酸硼酸锂、焦磷酸锂、十二烷基苯磺酸锂、十二烷基硫酸锂、柠檬酸三锂、偏硼酸锂、硼酸锂、钼酸锂、钨酸锂、溴化锂、亚硝酸锂、碘酸锂、碘化锂、硅酸锂、木质素磺酸锂、草酸锂、铝酸锂、甲基磺酸锂、醋酸锂、重铬酸锂、六氟砷酸锂、四氟硼酸锂、高氯酸锂、三氟甲烷磺酰亚胺钾(LiTFSI)、LiCF ₃SO ₃、以及LiN(SO ₂CF ₃) ₂中的一种或几种，且浓度范围为0.1～10mol/L。 The present application is also not particularly limited to lithium salts as electrolytes, as long as they can dissociate into cations and anions. For example, it may include lithium hexafluorophosphate, lithium chloride, lithium fluoride, lithium sulfate, lithium carbonate, lithium phosphate, lithium nitrate, lithium difluorooxalate borate, lithium pyrophosphate, lithium dodecylbenzenesulfonate, lithium dodecylsulfate , Trilithium citrate, lithium metaborate, lithium borate, lithium molybdate, lithium tungstate, lithium bromide, lithium nitrite, lithium iodate, lithium iodide, lithium silicate, lithium lignosulfonate, lithium oxalate, aluminate Lithium, lithium methanesulfonate, lithium acetate, lithium dichromate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium perchlorate, potassium trifluoromethanesulfonimide (LiTFSI), LiCF ₃ SO ₃ , and One or more of LiN(SO ₂ CF ₃ ) ₂ and the concentration range is 0.1 to 10 mol/L.

优选地，所述电解质锂盐为六氟磷酸锂。Preferably, the electrolyte lithium salt is lithium hexafluorophosphate.

进一步的，本申请实施例中电解液增加了添加剂，添加剂包括酯类、砜类、醚类、腈类或烯烃类有机添加剂的一种或几种，添加剂在电解液中的添加量为0.1～20wt％。添加剂包括氟代碳酸乙烯酯、碳酸亚乙烯酯、碳酸乙烯亚乙酯、1,3-丙磺酸内酯、1,4-丁磺酸内酯、硫酸乙烯酯、硫酸丙烯酯、硫酸亚乙酯、亚硫酸乙烯酯、亚硫酸丙烯酯、二甲基亚硫酸酯、二乙基亚硫酸酯、亚硫酸亚乙酯、氯代甲酸甲脂、二甲基亚砜、苯甲醚、乙酰胺、二氮杂苯、间二氮杂苯、冠醚12-冠-4、冠醚18-冠-6、4-氟苯甲醚、氟代链状醚、二氟代甲基碳酸乙烯酯、三氟代甲基碳酸乙烯酯、氯代碳酸乙烯酯、溴代碳酸乙烯酯、三氟乙基膦酸、溴 代丁内酯、氟代乙酸基乙烷、磷酸酯、亚磷酸酯、磷腈、乙醇胺、碳化二甲胺、环丁基砜、1,3-二氧环戊烷、乙腈、长链烯烃、三氧化二铝、氧化镁、氧化钡、碳酸钠、碳酸钙、二氧化碳、二氧化硫、以及碳酸锂中的一种或几种。Further, in the embodiment of the present application, the electrolyte has added additives. The additives include one or more of organic additives such as esters, sulfones, ethers, nitriles or olefins. The amount of additives added in the electrolyte is 0.1 to 20wt%. Additives include fluoroethylene carbonate, vinylene carbonate, ethylene ethylene carbonate, 1,3-propane sultone, 1,4-butane sultone, vinyl sulfate, propylene sulfate, ethylene sulfate Ester, vinyl sulfite, propylene sulfite, dimethyl sulfite, diethyl sulfite, ethylene sulfite, methyl chloroformate, dimethyl sulfoxide, anisole, acetamide , Diazabenzene, m-diazepine, crown ether 12-crown-4, crown ether 18-crown-6, 4-fluoroanisole, fluorochain ether, difluoromethyl vinyl carbonate, Trifluoromethyl ethylene carbonate, chloroethylene carbonate, bromoethylene carbonate, trifluoroethylphosphonic acid, bromobutyrolactone, fluoroacetoxyethane, phosphate, phosphite, phosphazene , Ethanolamine, carbodimethylamine, cyclobutyl sulfone, 1,3-dioxolane, acetonitrile, long-chain olefins, aluminum oxide, magnesium oxide, barium oxide, sodium carbonate, calcium carbonate, carbon dioxide, sulfur dioxide, And one or more of lithium carbonate.

进一步的，本申请实施例提供的锂离子电池所使用的隔膜的成分为绝缘的多孔聚合物薄膜或无机多孔薄膜，可以选用多孔聚丙烯薄膜、多孔聚乙烯薄膜、多孔复合聚合物薄膜、玻璃纤维纸或多孔陶瓷隔膜中的一种或几种。Further, the composition of the separator used in the lithium ion battery provided in the examples of the present application is an insulating porous polymer film or an inorganic porous film, and a porous polypropylene film, a porous polyethylene film, a porous composite polymer film, and glass fiber may be used One or more of paper or porous ceramic separators.

优选的，本申请实施例提供的正极活性材料层还包括导电剂以及粘结剂，其中正极活性材料的含量为60～90wt％，导电剂的含量为5～30wt％，粘结剂的含量为5～10wt％。同时，导电剂和粘结剂没有特别的限制，采用本领域常用的即可。例如，导电剂为导电炭黑、导电碳球、导电石墨、碳纳米管、导电碳纤维、石墨烯、还原氧化石墨烯中的一种或多种。例如，粘结剂为聚偏氟乙烯、聚四氟乙烯、聚乙烯醇、羧甲基纤维素、SBR橡胶、以及聚烯烃类中的一种或多种。Preferably, the positive electrode active material layer provided in the embodiments of the present application further includes a conductive agent and a binder, wherein the content of the positive electrode active material is 60 to 90 wt%, the content of the conductive agent is 5 to 30 wt%, and the content of the binder is 5～10wt%. At the same time, the conductive agent and the binder are not particularly limited, and only those commonly used in the art may be used. For example, the conductive agent is one or more of conductive carbon black, conductive carbon spheres, conductive graphite, carbon nanotubes, conductive carbon fiber, graphene, and reduced graphene oxide. For example, the binder is one or more of polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, carboxymethyl cellulose, SBR rubber, and polyolefins.

再者，本申请还提供了一种锂离子电池的制备方法，该方法包括：Furthermore, the present application also provides a method for preparing a lithium ion battery. The method includes:

步骤201：制备电池负极：将金属箔片裁切成所需的尺寸，然后干燥作为电池负极及负极集流体，或者按一定比例称取负极活性材料、导电剂以及粘结剂，加入适当溶剂中充分混合成均匀浆料制成负极活性材料层；将负极集流体清洗干净，然后将所述负极活性材料层均匀涂覆于负极集流体表面，待所述负极活性材料层完全干燥后进行裁切，得所需尺寸的电池负极。Step 201: Prepare battery negative electrode: Cut the metal foil to the required size, and then dry it as the battery negative electrode and negative electrode current collector, or weigh the negative electrode active material, conductive agent and binder according to a certain proportion, and add it to the appropriate solvent Fully mix into a uniform slurry to make a negative electrode active material layer; clean the negative electrode current collector, then apply the negative electrode active material layer evenly on the surface of the negative electrode current collector, and cut after the negative electrode active material layer is completely dry , To get the negative battery of the required size.

步骤202：配制电解液：称取一定量锂盐电解质加入到相应溶剂中，充分搅拌溶解。Step 202: Prepare electrolyte solution: Weigh a certain amount of lithium salt electrolyte into the corresponding solvent, and stir to dissolve.

步骤203：制备隔膜：将隔膜裁切成所需尺寸，清洗干净。Step 203: Preparation of the diaphragm: the diaphragm is cut to a desired size and cleaned.

步骤204：制备电池正极，按一定比例称取正极活性材料、导电剂以及粘结剂，加入适当溶剂中充分混合成均匀浆料制成正极活性材料层；将正极集流体清洗干净，然后将所述正极活性材料层均匀涂覆于正极集流体表面，待所述正极活性材料层完全干燥后进行裁切，得所需尺寸的电池正极。Step 204: prepare a battery positive electrode, weigh the positive electrode active material, conductive agent and binder in a certain proportion, add an appropriate solvent and mix it into a uniform slurry to make a positive electrode active material layer; clean the positive electrode current collector, and then The positive electrode active material layer is uniformly coated on the surface of the positive electrode current collector. After the positive electrode active material layer is completely dried, it is cut to obtain a battery positive electrode of a desired size.

步骤205：利用所述电池负极、电解液、隔膜以及电池正极进行组装。Step 205: Assemble using the battery negative electrode, electrolyte, separator, and battery positive electrode.

上述方法简洁、安全、高效，所用原料均储量丰富、价格低廉、易于获得、且环境友好。The above method is simple, safe and efficient, and the raw materials used are rich in reserves, low in price, easy to obtain, and environmentally friendly.

需要说明的是尽管上述步骤201-204是以特定顺序描述了本申请制备方法的操作，但是，这并非要求或者暗示必须按照该特定顺序来执行这些操作。步骤201-204的制备可以同时或者任意先后执行。It should be noted that although the above steps 201-204 describe the operations of the preparation method of the present application in a specific order, this does not require or imply that these operations must be performed in the specific order. The preparation of steps 201-204 can be performed simultaneously or in any order.

经电化学性能测试，上述正极活性材料Li ₂TMC ₄O ₈在锂离子电池中表现出良好的充放电性能，如图6所示。同时，经非原位测试不同状态下的正极材料(图6中的a、b、c点)， 结果表明草酸根离子和过渡金属离子均发生变价，表现出双离子氧化还原活性。 After electrochemical performance tests, the above-mentioned positive electrode active material Li ₂ TMC ₄ O ₈ showed good charge and discharge performance in lithium ion batteries, as shown in FIG. 6. At the same time, after ex-situ testing of the positive electrode materials in different states (points a, b, and c in Fig. 6), the results showed that both oxalate ions and transition metal ions changed in value, showing dual ion redox activity.

第六方面，在至少一个实施例中提供一种包含上述的锂离子电池的电子装置、电动工具、电动车辆或电力储存***。According to a sixth aspect, in at least one embodiment, an electronic device, an electric tool, an electric vehicle, or an electric power storage system including the lithium-ion battery described above is provided.

将本申请的锂离子电池应用到如手机、相机、电脑、电动车等装置中时，有助于延长这些装置的使用时间，具有更优异的电化学性能。When the lithium ion battery of the present application is applied to devices such as mobile phones, cameras, computers, electric vehicles, etc., it helps to extend the use time of these devices and has more excellent electrochemical performance.

以上可以看出，本申请与现有技术相比主要具有以下特点：As can be seen from the above, the present application mainly has the following characteristics compared with the prior art:

(1)在电池充放电过程中，正极活性材料的酸根离子与过渡金属离子共同提供电化学活性，这有利于提升电池能量密度；此外，其三维结构稳定，有利于提高电池的安全性和循环稳定性。即，相对于传统氧化物型锂离子电池正极材料，聚阴离子型正极活性材料的结构更加稳定，有利于提高电池的安全性和循环性能。(1) During the battery charging and discharging process, the acid ion of the positive electrode active material and the transition metal ion together provide electrochemical activity, which is conducive to improving the energy density of the battery; in addition, its three-dimensional structure is stable, which is conducive to improving the safety and cycle of the battery stability. That is, the structure of the polyanionic positive electrode active material is more stable than that of the conventional oxide-type lithium ion battery positive electrode material, which is beneficial to improve the safety and cycle performance of the battery.

(2)此锂离子电池利用正极材料的双活性特征，伴随着正极材料中阴离子和过渡金属的得失电子，锂离子发生可逆的嵌入-脱嵌反应，从而实现电池充放电过程。相对于现有锂离子电池，其反应机理新颖，有利于充分利用酸根离子，降低正极材料中的非活性质量，提高电池的容量。(2) This lithium-ion battery utilizes the dual-active characteristics of the positive electrode material. With the gain and loss of electrons of the anion and transition metal in the positive electrode material, lithium ions undergo a reversible intercalation-deintercalation reaction, thereby realizing the battery charging and discharging process. Compared with the existing lithium ion battery, the reaction mechanism is novel, which is beneficial to make full use of acid ion, reduce the inactive quality in the positive electrode material, and increase the capacity of the battery.

(3)正极活性材料为具有三维晶体结构的有机聚阴离子化合物，所用材料均储量丰富、便宜易得；所用合成工艺简洁、迅速、有效，对于提高材料合成效率、降低材料制备成本具有重要作用。(3) The positive electrode active material is an organic polyanion compound with a three-dimensional crystal structure. The materials used are rich in reserves and cheap and easy to obtain; the synthesis process used is simple, rapid and effective, and plays an important role in improving the efficiency of material synthesis and reducing the cost of material preparation.

(4)该新化合物的用途为锂离子电池的正极材料，该锂离子电池正极包括具有三维晶体结构的聚阴离子化合物，负极为常规材料，电解液为含有锂盐的有机溶液。所有材料均储量丰富、便宜易得，且均是环境友好型材料，不会造成环境污染，对于降低二次电池的价格具有重要作用。(4) The new compound is used as a positive electrode material of a lithium ion battery. The positive electrode of the lithium ion battery includes a polyanion compound having a three-dimensional crystal structure, the negative electrode is a conventional material, and the electrolyte is an organic solution containing a lithium salt. All materials are rich in reserves, cheap and easy to obtain, and are all environmentally friendly materials, which will not cause environmental pollution and play an important role in reducing the price of secondary batteries.

应当指出，上述实施方式仅为本申请的优选实施方式，不能以此来限定本申请保护的范围，本领域的技术人员在本申请的基础上所做的任何非实质性的变化及替换均属于本申请所要求保护的范围。It should be noted that the above-mentioned embodiments are only preferred embodiments of the present application, and the scope of protection of the present application cannot be limited by this. Any non-substantial changes and replacements made by those skilled in the art on the basis of the present application belong to The scope of protection claimed in this application.

下面通过具体的实施例进一步说明上述正极活性材料及其制备方法，以及锂离子电池及其制备方法，但是，应当理解为，这些实施例仅仅是用于更详细地说明之用，而不应理解为用于以任何形式限制本申请。The following further describes the above-mentioned positive electrode active material and its preparation method, as well as the lithium ion battery and its preparation method through specific examples, but it should be understood that these examples are only for more detailed explanation, and should not be understood For restricting this application in any form.

实施例1Example 1

一种草酸盐材料，化学式为Li ₂FeC ₄O ₈。 An oxalate material with the chemical formula Li ₂ FeC ₄ O ₈ .

所述草酸盐材料料的制备方法，包括：The preparation method of the oxalate material includes:

准确称量FeCl ₂·4H ₂O 0.7425g，Li ₂CO ₃ 0.5543g，H ₂C ₂O ₄·2H ₂O 1.26g，在玛瑙研钵中研磨均匀，转移到容积为25mL的聚四氟乙烯反应罐，再以不锈钢反应釜密封；将此反应釜 直接置于190℃烘箱，搁置3天后取出，于空气中冷却至室温；打开反应釜后将产物抽滤，抽滤过程中以去离子水反复清洗直至产物为均一淡黄色，用无水乙醇快速冲洗并抽滤；将抽滤所得固体置于80℃烘箱，搁置12小时后取出，经不锈钢筛子分级，去除300目以上的最小粒径的颗粒，剩余产物研磨成粉末后经粉末X射线衍射确认其产物为LFO化合物,确定其为纯相。 Accurately weigh 0.7425g of FeCl ₂ ·4H ₂ O, 0.5543g of Li ₂ CO _3, 1.26g of H ₂ C ₂ O ₄ ·2H ₂ O, grind evenly in an agate mortar, and transfer to 25mL polytetrafluoroethylene The reaction tank is sealed with a stainless steel reactor; put the reactor directly in an oven at 190°C, let it stand for 3 days, take it out, and cool it to room temperature in the air; after opening the reactor, the product is suction filtered, and deionized water is used during the suction filtration process Wash repeatedly until the product is uniform light yellow, quickly rinse with anhydrous ethanol and suction filtration; place the solid obtained by suction filtration in an 80°C oven, leave it for 12 hours, take it out, and classify it through a stainless steel sieve to remove the smallest particle size above 300 mesh After the particles and the remaining product were ground into powder, the product was confirmed to be an LFO compound by powder X-ray diffraction, and it was determined to be a pure phase.

实施例2Example 2

一种草酸盐材料，化学式为Li ₂FeC ₄O ₈。 An oxalate material with the chemical formula Li ₂ FeC ₄ O ₈ .

所述草酸盐材料的制备方法，与实施例1的区别仅在于：The preparation method of the oxalate material differs from Example 1 only in that:

准确称量FeC ₂O ₄·2H ₂O 0.495g，LiOH·H ₂O 0.628g，H ₂C ₂O ₄·2H ₂O 0.945g； Accurately weigh FeC ₂ O ₄ ·2H ₂ O 0.495g, LiOH·H ₂ O 0.628g, H ₂ C ₂ O ₄ ·2H ₂ O 0.945g;

将此反应釜直接置于180℃烘箱，搁置5天后取出。Place the reaction kettle directly in an oven at 180°C and leave it for 5 days before taking it out.

实施例3Example 3

一种草酸盐材料，化学式为Li ₂FeC ₄O ₈。 An oxalate material with the chemical formula Li ₂ FeC ₄ O ₈ .

所述草酸盐材料的制备方法，与实施例1的区别仅在于：The preparation method of the oxalate material differs from Example 1 only in that:

准确称量FeCl ₂·4H ₂O 0.7425g，LiOH·H ₂O 0.628g，H ₂C ₂O ₄·2H ₂O 1.26g。 Accurately weigh 0.7425 g of FeCl ₂ ·4H ₂ O, 0.628 g of LiOH·H ₂ O, and 1.26 g of H ₂ C ₂ O ₄ ·2H ₂ O.

实施例4Example 4

一种草酸盐材料，化学式为Li ₂MnC ₄O ₈。 An oxalate material with the chemical formula Li ₂ MnC ₄ O ₈ .

所述草酸盐材料的制备方法，包括：The preparation method of the oxalate material includes:

准确称量MnCl ₂·4H ₂O 0.7395g，Li ₂CO ₃ 0.5543g，H ₂C ₂O ₄·2H ₂O 1.26g，在玛瑙研钵中研磨均匀，转移到容积为25mL的聚四氟乙烯反应罐，再以不锈钢反应釜密封；将此反应釜直接置于190℃烘箱，搁置5天后取出，于空气中冷却至室温；打开反应釜后将产物抽滤，抽滤过程中以去离子水反复清洗直至产物为均一淡黄色，用无水乙醇快速冲洗并抽滤；将抽滤所得固体置于80℃烘箱，搁置12小时后取出，经不锈钢筛子分级，去除300目以上的最小粒径的颗粒，剩余产物研磨成粉末后经粉末X射线衍射确认其产物为LMO化合物,确定其为纯相。 Accurately weigh MnCl ₂ ·4H ₂ O 0.7395g, Li ₂ CO ₃ 0.5543g, H ₂ C ₂ O ₄ ·2H ₂ O 1.26g, grind evenly in an agate mortar, and transfer to 25mL polytetrafluoroethylene The reaction tank is sealed with a stainless steel reactor; put the reactor directly in an oven at 190°C, leave it for 5 days and take it out, and cool it to room temperature in the air; after opening the reactor, the product is suction filtered, and deionized water is used during the suction filtration process Wash repeatedly until the product is uniformly light yellow, quickly rinse with anhydrous ethanol and suction filtration; place the solid obtained by suction filtration in an 80°C oven, leave it for 12 hours, take it out, and classify it through a stainless steel sieve to remove the smallest particle size above 300 mesh After the particles and the remaining product were ground into powder, the product was confirmed to be a pure phase by powder X-ray diffraction.

实施例5Example 5

一种草酸盐材料，化学式为Li ₂MnC ₄O ₈。 An oxalate material with the chemical formula Li ₂ MnC ₄ O ₈ .

所述草酸盐材料的制备方法，与实施例4的区别仅在于：The preparation method of the oxalate material differs from Example 4 only in that:

准确称量Mn(CH ₃COO) ₂·4H ₂O 0.9190g，Li ₂CO ₃ 0.5543g，H ₂C ₂O ₄·2H ₂O 1.26g。 Accurately weigh Mn(CH ₃ COO) ₂ · 4H ₂ O 0.9190g, Li ₂ CO ₃ 0.5543g, H ₂ C ₂ O ₄ · 2H ₂ O 1.26g.

实施例6Example 6

一种草酸盐材料，化学式为Li ₂MnC ₄O ₈。 An oxalate material with the chemical formula Li ₂ MnC ₄ O ₈ .

所述草酸盐材料的制备方法，与实施例4的区别仅在于：The preparation method of the oxalate material differs from Example 4 only in that:

准确称量MnCl ₂·4H ₂O 0.7395g，Li ₂CO ₃ 0.5543g，H ₂C ₂O ₄·2H ₂O 1.26g，在玛瑙研钵中研 磨均匀，转移到容积为25mL的对位聚苯反应罐，再以不锈钢反应釜密封。 Accurately weigh MnCl ₂ ·4H ₂ O 0.7395g, Li ₂ CO ₃ 0.5543g, H ₂ C ₂ O ₄ ·2H ₂ O 1.26g, grind evenly in an agate mortar, and transfer to 25-mL para-polyphenyl The reaction tank is sealed with a stainless steel reactor.

实施例7-30Examples 7-30

实施例7-30与实施例1的不同之处在于，各原料的类型、配比，反应罐以及反应条件，具体如表1所示。The difference between Examples 7-30 and Example 1 is that the types, proportions, reaction tanks and reaction conditions of each raw material are shown in Table 1.

表1实施例7-30的草酸盐材料及制备中的主要操作条件Table 1 Examples 7-30 of oxalate materials and main operating conditions in preparation

注：表1中，原料2均为Li ₂CO ₃，用量为0.5543g；原料3均为H ₂C ₂O ₄·2H ₂O，用量1.26g。 Note: In Table 1, the raw materials 2 are all Li ₂ CO ₃ and the dosage is 0.5543g; the raw materials 3 are all H ₂ C ₂ O ₄ · 2H ₂ O and the dosage is 1.26g.

将上述草酸盐材料作为正极活性材料应用到锂离子电池中。The above oxalate material is applied as a positive electrode active material to a lithium ion battery.

实施例31Example 31

一种锂离子电池，包括实施例1所述的草酸盐材料(正极活性材料)、正极集流体、负极、电解液和隔膜。A lithium ion battery includes the oxalate material (positive electrode active material), positive electrode current collector, negative electrode, electrolyte, and separator described in Example 1.

所述锂离子电池的制备方法包括：准确称量0.35g实施例1制得的正极活性材料LFO，0.10g科琴黑导电碳，0.05g聚偏氟乙烯，研磨均匀后转入玛瑙研磨罐，用高能球磨机研磨30分钟；取出后在NMP中分散成均匀的浆料，涂覆于厚度20微米的铝箔；充分干燥后裁成直径10微米的小原片。以该小原片为正极，金属锂片为负极，溶有1M LiPF ₆的聚碳酸酯为电解液，在氩气保护的手套箱将上述电池正极、隔膜、电解液、电池负极依次排放，再经过封口完成扣式电池的制备。 The preparation method of the lithium-ion battery includes: accurately weighing 0.35 g of the positive electrode active material LFO prepared in Example 1, 0.10 g of Ketjen black conductive carbon, and 0.05 g of polyvinylidene fluoride. After uniform grinding, it is transferred to an agate grinding tank. Grind with a high-energy ball mill for 30 minutes; disperse it into a uniform slurry in NMP after taking it out, and coat it on an aluminum foil with a thickness of 20 microns; fully dry and cut into small original pieces with a diameter of 10 microns. Taking the small original sheet as the positive electrode, the lithium metal sheet as the negative electrode, and the polycarbonate dissolved with 1M LiPF ₆ as the electrolyte, the battery positive electrode, the separator, the electrolyte, and the battery negative electrode are sequentially discharged in a glove box protected by argon, and then pass through The sealing completes the preparation of the button battery.

实施例32Example 32

一种锂离子电池，包括实施例1所述的正极活性材料、正极集流体、负极、电解液和隔膜。A lithium ion battery includes the positive electrode active material, the positive electrode current collector, the negative electrode, the electrolyte, and the separator described in Example 1.

所述锂离子电池的制备方法包括：准确称量0.30g LFO，0.15g科琴黑导电碳，0.05g聚偏氟乙烯，研磨均匀后转入玛瑙研磨罐，用高能球磨机研磨30分钟；取出后充分干燥，用油压机压制成直径10微米的小原片。以该小原片为正极，金属锂片为负极，溶有1M LiClO ₄的聚碳酸酯为电解液，在氩气保护的手套箱将上述电池正极、隔膜、电解液、电池负极依次排放，再经过封口完成扣式电池的制备。 The preparation method of the lithium-ion battery includes: accurately weighing 0.30g LFO, 0.15g Ketjen black conductive carbon, 0.05g polyvinylidene fluoride, evenly ground and transferred to an agate grinding tank, and ground with a high-energy ball mill for 30 minutes; after removal Dry thoroughly and use a hydraulic press to make small original pieces with a diameter of 10 microns. Take the small original sheet as the positive electrode, the metal lithium sheet as the negative electrode, and the polycarbonate dissolved with 1M LiClO ₄ as the electrolyte. The sealing completes the preparation of the button battery.

实施例33-60Examples 33-60

实施例33-60与实施例31的不同之处在于，锂离子电池中的正极、负极、隔膜和电解液，具体如表2所示。Examples 33-60 are different from Example 31 in that the positive electrode, negative electrode, separator and electrolyte in the lithium ion battery are shown in Table 2.

表2实施例33-60的锂离子电池Table 2 Lithium-ion batteries of Examples 33-60

注：表2中，实施例33-60的正极活性材料部分选自上述实施例1-30的部分正极活性材料。Note: In Table 2, the positive electrode active material parts of Examples 33-60 are selected from the part of the positive electrode active materials of Examples 1-30 described above.

对比例1Comparative Example 1

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的聚阴离子型正极活性材料，化学式为Li ₂Fe(SO ₄) ₂。 In this comparative example, the positive electrode active material is an existing polyanionic positive electrode active material, and the chemical formula is Li ₂ Fe(SO ₄ ) ₂ .

对比例2Comparative Example 2

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的聚阴离子型正极活性材料，化学式为LiFePO ₄。 In this comparative example, the positive electrode active material is an existing polyanionic positive electrode active material, and the chemical formula is LiFePO ₄ .

对比例3Comparative Example 3

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的聚阴离子型正极活性材料，化学式为Li ₂FeSiO ₄。 In this comparative example, the positive electrode active material is an existing polyanionic positive electrode active material, and the chemical formula is Li ₂ FeSiO ₄ .

对比例4Comparative Example 4

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的聚阴离子型正极活性材料，化学式为LiFeSO ₄F。 In this comparative example, the positive electrode active material is an existing polyanionic positive electrode active material, and the chemical formula is LiFeSO ₄ F.

对比例5Comparative Example 5

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的氧化物型正极活性材料，化学式为LiMn ₂O ₄。 In this comparative example, the positive electrode active material is an existing oxide-type positive electrode active material, and the chemical formula is LiMn ₂ O ₄ .

对比例6Comparative Example 6

一种锂离子电池，与实施例31的不同之处在于正极活性材料；A lithium ion battery, which differs from Example 31 in the positive electrode active material;

本对比例中，正极活性材料为现有的氧化物型正极活性材料，化学式为 LiNi _0.8Co _0.15Al _0.05O ₂。 In this comparative example, the positive electrode active material is an existing oxide-type positive electrode active material, and the chemical formula is LiNi _0.8 Co _0.15 Al _0.05 O ₂ .

性能测试Performance Testing

对上述实施例31-60以及对比例1-6的锂离子电池进行性能测试，包括恒流充放电测试、电化学循环伏安曲线测试；测试结果参见表3。The performance tests were performed on the lithium ion batteries of Examples 31-60 and Comparative Examples 1-6, including constant current charge and discharge tests and electrochemical cyclic voltammetry tests; for test results, see Table 3.

其中，恒流充放电测试采用市售电池测试仪，环境为恒温恒湿房(30℃，35％)，电池正极负载量为2-5mg/cm ²,电池充放电电流密度为100mA/g，循环次数设定为1000圈；当比容量下降为初始比容量的50％时手动停止测试。电化学循环伏安曲线采用市售电化学工作站，测试电压的初始上下限设定为1.5V和4.5V，步进为0.1-10mV/s,经优化确定最终电压范围和最佳步进。 Among them, the constant current charge and discharge test uses a commercially available battery tester, the environment is a constant temperature and humidity room (30 ℃, 35%), the battery positive load is 2-5mg/cm ² , and the battery charge and discharge current density is 100mA/g. The number of cycles is set to 1000 cycles; when the specific capacity drops to 50% of the initial specific capacity, the test is manually stopped. The electrochemical cyclic voltammetry curve uses a commercially available electrochemical workstation. The initial upper and lower limits of the test voltage are set to 1.5V and 4.5V in steps of 0.1-10mV/s. The final voltage range and optimal step are determined through optimization.

表3实施例及对比例的锂离子电池性能测试结果Table 3 Examples and comparative examples of lithium ion battery performance test results

由表3可以看出，本申请中经优选的实施例(如实施例31-37)，较已有的氧化物正极材料具有更好的循环稳定性，较已有的聚阴离子型正极材料具有更高的相对比容量和可媲美的工作电压区间。It can be seen from Table 3 that the preferred examples in this application (such as Examples 31-37) have better cycle stability than the existing oxide cathode materials, and have better than the existing polyanion cathode materials Higher relative specific capacity and comparable operating voltage range.

最后应说明的是：以上各实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述各实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分或者全部技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。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 (10)

1. 一种草酸盐材料，其特征在于，所述草酸盐材料具有如下化学组成：Li ₂TMC ₄O ₈，其中，TM为正二价的过渡金属。 An oxalate material, characterized in that the oxalate material has the following chemical composition: Li ₂ TMC ₄ O ₈ , where TM is a positive divalent transition metal.
2. 根据权利要求1所述的草酸盐材料，其特征在于，所述过渡金属包括Ti、V、Cr、Mn、Fe、Co、Ni、Cu和Zn中的至少一种，优选包括Fe、Mn、Co、Ni、Cu和Zn中的至少一种，进一步优选为Fe和/或Mn。The oxalate material according to claim 1, wherein the transition metal includes at least one of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, preferably including Fe, Mn, At least one of Co, Ni, Cu, and Zn is further preferably Fe and/or Mn.
3. 根据权利要求1所述的草酸盐材料，其特征在于，所述草酸盐材料为异质同构体，具有三维结构，晶系属于单斜晶系，空间群为P2 ₁/n。 The oxalate material according to claim 1, characterized in that the oxalate material is a heterogeneous isoform with a three-dimensional structure, the crystal system belongs to a monoclinic crystal system, and the space group is P2 ₁ /n.
4. 根据权利要求1～3任一项所述的草酸盐材料，其特征在于，所述草酸盐材料为草酸亚铁锂，分子式为Li ₂FeC ₄O ₈，属于单斜晶系，空间群为P2 ₁/n，分解温度为290～310℃，单胞参数为

   

   α＝γ＝90°，β＝110.93(1)°，

   

   Z＝4； The oxalate material according to any one of claims 1 to 3, characterized in that the oxalate material is lithium ferrous oxalate and the molecular formula is Li ₂ FeC ₄ O ₈ , belonging to the monoclinic system, space group Is P2 ₁ /n, the decomposition temperature is 290～310℃, and the unit cell parameter is

   

   α=γ=90°, β=110.93(1)°,

   

   Z=4;

   和/或，所述草酸盐材料为草酸锰锂，分子式为Li ₂MnC ₄O ₈，属于单斜晶系，空间群为P2 ₁/n，分解温度为300～320℃，单胞参数为

   

   

   α＝γ＝90°，β＝110.699(7)°，

   

   Z＝4。 And/or, the oxalate material is lithium manganese oxalate, the molecular formula is Li ₂ MnC ₄ O ₈ , which belongs to the monoclinic crystal system, the space group is P2 ₁ /n, the decomposition temperature is 300～320℃, and the unit cell parameter is

   

   

   α=γ=90°, β=110.699(7)°,

   

   Z=4.
5. 权利要求1～4任一项所述的草酸盐材料的制备方法，其特征在于，将锂源、过渡金属源和草酸源混合，进行溶剂热反应，得到所述草酸盐材料；The method for preparing an oxalate material according to any one of claims 1 to 4, wherein a lithium source, a transition metal source and an oxalic acid source are mixed, and a solvothermal reaction is performed to obtain the oxalate material;

   优选地，所述过渡金属源包括过渡金属钛源、过渡金属钒源、过渡金属铬源、过渡金属锰源、过渡金属铁源、过渡金属钴源、过渡金属镍源、过渡金属铜源和过渡金属锌源中的至少一种；Preferably, the transition metal source includes a transition metal titanium source, a transition metal vanadium source, a transition metal chromium source, a transition metal manganese source, a transition metal iron source, a transition metal cobalt source, a transition metal nickel source, a transition metal copper source and a transition metal At least one of metal zinc sources;

   优选地，所述过渡金属源包括过渡金属单质、过渡金属氧化物、过渡金属氢氧化物、过渡金属卤化物、过渡金属硫酸盐、过渡金属磷酸盐、过渡金属硝酸盐、过渡金属碳酸盐、过渡金属甲酸盐、过渡金属乙酸盐、过渡金属草酸盐、过渡金属铵盐、过渡金属酯化物及其水合物中的至少一种；Preferably, the transition metal source includes transition metal element, transition metal oxide, transition metal hydroxide, transition metal halide, transition metal sulfate, transition metal phosphate, transition metal nitrate, transition metal carbonate, At least one of transition metal formate, transition metal acetate, transition metal oxalate, transition metal ammonium salt, transition metal ester and its hydrate;

   优选地，所述锂源包括碳酸锂、氢氧化锂、偏硼酸锂、钼酸锂、硫酸锂、四氟硼酸锂、磷酸锂、四氯铜酸锂、四硼酸锂、草酸锂、铬酸锂、三氟甲磺酸锂及其水合物中的至少一种；Preferably, the lithium source includes lithium carbonate, lithium hydroxide, lithium metaborate, lithium molybdate, lithium sulfate, lithium tetrafluoroborate, lithium phosphate, lithium tetrachlorocuprate, lithium tetraborate, lithium oxalate, lithium chromate , At least one of lithium trifluoromethanesulfonate and its hydrate;

   优选地，所述草酸源包括草酸、草酸水合物、草酸盐和草酸盐水合物中的至少一种。Preferably, the oxalic acid source includes at least one of oxalic acid, oxalic acid hydrate, oxalate and oxalate hydrate.
6. 根据权利要求5所述的草酸盐材料的制备方法，其特征在于，过渡金属源、锂源、草酸源与溶剂的摩尔比为1：(1～20)：(8～40)：(3～400)，优选为1：(4～ 8)：(8～40)：(8～40)；The method for preparing an oxalate material according to claim 5, wherein the molar ratio of the transition metal source, lithium source, oxalic acid source and solvent is 1: (1-20): (8-40): (3 ~400), preferably 1: (4-8): (8-40): (8-40);

   优选地，溶剂热反应的温度为160～260℃，优选为180～250℃；Preferably, the temperature of the solvothermal reaction is 160-260°C, preferably 180-250°C;

   和/或，溶剂热反应的时间为2～180小时，优选为4～168小时；And/or, the solvothermal reaction time is 2 to 180 hours, preferably 4 to 168 hours;

   优选地，反应所用反应器的材质为聚四氟乙烯或者对位聚苯；Preferably, the material of the reactor used for the reaction is polytetrafluoroethylene or para-polyphenylene;

   优选地，溶剂热反应之后还包括分离、洗涤和干燥的步骤；Preferably, the solvothermal reaction further includes steps of separation, washing and drying;

   优选地，分离包括离心、超声、过滤和粒径分级中的至少一种；Preferably, the separation includes at least one of centrifugation, ultrasound, filtration and particle size classification;

   优选地，干燥的温度为40～120℃，干燥的压力为≤20kPa，时间为10～24小时。Preferably, the drying temperature is 40 to 120° C., the drying pressure is ≤20 kPa, and the time is 10 to 24 hours.
7. 权利要求1～4任一项所述的草酸盐材料或权利要求5～6任一项所述的草酸盐材料的制备方法得到的草酸盐材料作为锂离子电池正极活性材料的用途。Use of the oxalate material according to any one of claims 1 to 4 or the oxalate material obtained by the preparation method of any one of claims 5 to 6 as a positive electrode active material for a lithium ion battery.
8. 一种锂离子电池正极材料，其特征在于，包括权利要求1～4任一项所述的草酸盐材料或权利要求5～6任一项所述的草酸盐材料的制备方法得到的草酸盐材料。A positive electrode material for lithium ion batteries, characterized by comprising the oxalate material according to any one of claims 1 to 4 or the grass obtained by the preparation method of the oxalate material according to any one of claims 5 to 6. Salt material.
9. 一种锂离子电池，其特征在于，包括正极、负极、介于正极和负极之间的隔膜以及电解液；A lithium ion battery, characterized by comprising a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode, and an electrolyte;

   其中，所述正极包括权利要求8所述的锂离子电池正极材料。Wherein, the positive electrode includes the positive electrode material for a lithium ion battery according to claim 8.
10. 包含权利要求9所述的锂离子电池的电子装置、电动工具、电动车辆或电力储存***。An electronic device, a power tool, an electric vehicle, or a power storage system including the lithium ion battery of claim 9.

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