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WO2021217684A1 - 一种高浓度溶液及其应用与制备方法 - Google Patents

一种高浓度溶液及其应用与制备方法 Download PDF

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WO2021217684A1
WO2021217684A1 PCT/CN2020/088550 CN2020088550W WO2021217684A1 WO 2021217684 A1 WO2021217684 A1 WO 2021217684A1 CN 2020088550 W CN2020088550 W CN 2020088550W WO 2021217684 A1 WO2021217684 A1 WO 2021217684A1
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concentration
ions
solution
zinc
bromide
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高超
蔡盛赢
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Zhejiang University ZJU
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Zhejiang University ZJU
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
    • H01M10/0562—Solid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/36—Accumulators not provided for in groups H01M10/05-H01M10/34
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

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  • the present invention relates to a high-concentration solution and its application in an aqueous dual-ion battery.
  • the concentration of the solution can reach more than 30 mol kg -1 and can greatly promote the specific capacity of the battery.
  • An object of the present invention is to provide a high-concentration aqueous solution suitable for use in electrolyte.
  • the solution contains at least zinc ions, bromide ions and chloride ions, wherein the concentration of zinc ions is above 30 mol kg -1.
  • the solution includes at least two solutes of zinc chloride and zinc bromide dissolved in water.
  • the solution composed of zinc bromide and zinc chloride through the "multi-salt co-dissolution" function, that is, the high-concentration salt solution serves as a new
  • the solvent dissolves another unhydrated salt and forms a new "dissolved salt mixture", which greatly increases the concentration of the solution.
  • the concentration of the zinc ion can reach more than 30 mol kg -1 , and the concentration mol kg -1 refers to It is the amount of solute dissolved per kilogram of water.
  • zinc bromide and zinc chloride can be in any ratio.
  • concentration of bromide ion is in the range of 15-90 mol kg -1
  • concentration of chloride ion is in the range of 15-90 mol kg -1 .
  • concentration ratio of bromide ion to chloride ion is 1:3, which can effectively increase the zinc ion concentration in the dual system solution.
  • Another object of the present invention is to provide an ultra-high concentration solution, which also contains acetate ions, specifically, contains solute zinc acetate, and further through the "end-capping" effect of zinc acetate, the salt cannot continue to aggregate and grow, and then The inorganic oligomers with larger molecular weights stably exist in the solution.
  • the concentration of zinc ions should be below 50 mol kg -1 and the concentration of acetic acid high ions should be below 10 mol kg -1 .
  • Another object of the present invention is the application of the above solution in the battery electrolyte.
  • the high-concentration electrolyte not only effectively inhibits the electrolysis of water, but also reduces the oxidation potential of bromide ions, and promotes the insertion of bromine in the battery cathode material. Layer, which greatly improves the specific capacity of the positive electrode ( ⁇ 638mAh g -1 ).
  • the increase in the concentration of active ions in the electrolyte can reduce the amount of electrolyte, which is beneficial to the improvement of the energy density of non-rocking chair batteries.
  • Another object of the present invention is the application of the above-mentioned solution in the battery electrolyte.
  • the high-concentration electrolyte realizes the breakthrough of the I-stage intercalation of bromine from the existing single-layer graphene to the macroscopic material (in the prior art, The I-order intercalation of bromine is only observed on the single-layer graphene, which can only achieve the II-order intercalation in the macrographite materials, and the single-layer graphene cannot be used industrially), which gives the battery cathode a high specific capacity.
  • the positive electrode of the battery uses carbon materials, especially carbon nanotubes, natural graphite, expanded graphite, graphene, graphene assemblies, and other carbon materials with a graphite lattice structure.
  • carbon materials especially carbon nanotubes, natural graphite, expanded graphite, graphene, graphene assemblies, and other carbon materials with a graphite lattice structure.
  • the negative electrode of the battery adopts a zinc negative electrode, including metallic zinc, zinc-containing alloy, or other inert conductive substrates that can support zinc.
  • Another object of the present invention is the preparation method of the above-mentioned high-concentration solution, which is specifically as follows:
  • the beneficial effect of the present invention is that the hybrid solute system of the present invention has properties that any single component does not possess, and its solubility in water is much higher than that of a single zinc chloride, zinc bromide or zinc acetate.
  • the high concentration of the two-component solution composed of zinc bromide and zinc chloride is derived from the "multi-salt co-dissolution" effect, that is, the highly concentrated salt solution acts as a new solvent to dissolve another unhydrated salt and form a new "Mixed Salt Mixture".
  • ultra-concentrated zinc chloride-zinc bromide-zinc acetate-water "copolymer” is based on another mechanism: when a large amount of electrolyte salt dissolved in water at high temperature is cooled to room temperature, due to the "end capping of acetate ion""It cannot continue to aggregate and grow, and then becomes inorganic oligomers with larger molecular weights that stably exist in the electrolyte solution instead of forming crystal grains.
  • the formation mechanism of the latter is completely different from the known “salt-in-water” and “water-in-salt” electrolytes.
  • the concentration is expressed by the ratio of solute to solvent.
  • 60-100 mol kg -1 means that the amount of solute dissolved per kilogram of water is 60-100 mol.
  • Figure 1 is the mass spectrum of the salt-water "copolymer" of Example 1. It can be seen from the figure that there are a large number of molecular ion peaks in the solution with a relative molecular mass greater than any component in the system, which means that the salt-water "copolymer” The presence of oligomers.
  • Figure 2 is a photograph of the salt-water "copolymer” electrolyte and its precursors of Example 1. It can be seen from the figure that the molar ratio of zinc chloride, zinc bromide and zinc acetate is 33.75:11.25:1 with a small amount of Water is mixed and heated in a specific stoichiometric ratio to form a colorless and transparent salt-water "copolymer" that is stable at room temperature.
  • Figure 3 is a constant current charge and discharge diagram of the battery of Example 1. It can be seen from the figure that its specific charge and discharge capacity is greater than 650 mAh g -1 at a current density of 1A g -1 , and the coulombic efficiency is greater than 95%.
  • Figure 4 is a cycle diagram of the battery of Example 1. It can be seen from the figure that its capacity retention rate is greater than 98% after being cycled for 200 cycles at a current density of 1A g -1.
  • Figure 5 is a photo of the electrolyte and its precursor of Example 2. It can be seen from the figure that the molar ratio of zinc chloride, zinc bromide and zinc acetate is 28:14:1 mixed with a small amount of water in a specific stoichiometric ratio After heating, a colorless and transparent salt-water "copolymer" that is stable at room temperature can be formed.
  • Figure 6 is a photograph of the water-phase eutectic salt electrolyte and its precursors of Example 3. It can be seen from the figure that the molar ratio of zinc chloride, zinc bromide and a small amount of water are mixed in a specific stoichiometric ratio of 3:1 After heating, a colorless, transparent, water-phase eutectic salt that is stable at room temperature can be formed.
  • Figure 7 is a photograph of the salt-water "copolymer" electrolyte of Example 4 and its precursor. It can be seen from the figure that the molar ratio of zinc chloride, zinc bromide and zinc acetate is 22.5:22.5:1 with a small amount of zinc chloride, zinc bromide and zinc acetate. Water is mixed and heated in a specific stoichiometric ratio to form a colorless and transparent salt-water "copolymer" that is stable at room temperature.
  • FIG 8 is a positive electrode material Example 1 Macro - positive graphene film in the salt - the electrochemical water "copolymer” in situ Raman spectra, it will be seen, the process of charging the graphene G band from 1579 cm - 1 becomes 1625cm -1 , which represents the formation of I-order Br intercalated graphite compound; the G peak changes back to 1579cm -1 during the discharge process, which proves that the charge-discharge process is completely reversible.
  • Figure 9 is the electrochemical in-situ XRD spectra of the macroscopic cathode material-graphene film cathode in the salt-water "copolymer" of Example 1. It can be seen that the (002) surface peak position of graphene varies from The original 26.5° changed to 25.3°, representing the formation of I-order Br intercalated graphite compound; during the discharge process, it changed back to 26.3°, which proved that the charge and discharge process is completely reversible.
  • the battery cell obtained through the above steps has a specific discharge capacity of 607.5mAh g -1 (calculated based on the positive active material, see Figure 3) at a current density of 1A g -1, and has excellent cycle stability. After 200 charge-discharge cycles, the capacity retention rate is greater than 98% (see Figure 4).
  • the battery charge-discharge process situ Raman and X- ray diffraction pattern of the graphene films are a positive electrode 8 and 9, it will be seen, the process of charging the graphene G peak position changes from 1579cm -1 1625cm - 1 , represents the formation of I-order Br intercalated graphite compound; the G peak changes back to 1579 cm -1 during the discharge process, which proves that the charge and discharge process is completely reversible.
  • the redox potential of anions is:
  • the increase of the total ion concentration in the electrolyte reduces the oxidation potential of bromide ions, increases the reduction potential of zinc ions, further avoids the side reaction of water molecules from oxygen evolution and hydrogen evolution, and helps to inhibit the "shuttle effect" of halogens and promote Its intercalation in macroscopic cathode materials.
  • the battery cell obtained through the above steps has a specific discharge capacity of 632mAh g -1 (calculated based on the active material of the positive electrode) at a current density of 1A g -1, and has good cycle stability.
  • the capacity retention rate after discharge cycles is greater than 90%.
  • the battery cell obtained through the above steps has a specific discharge capacity of 637 mAh g -1 (calculated based on the positive electrode active material) at a current density of 1A g -1, and has good cycle stability.
  • the capacity retention rate after discharge cycles is greater than 85%.
  • Example 1 The in-situ Raman test and XRD test were performed on the middle phase microsphere graphite anode during the charging and discharging process of the battery, and the analysis was carried out according to Example 1. -Stage intercalation, which gives the battery a high specific capacity of the positive electrode.
  • the battery cell obtained through the above steps has a specific discharge capacity of 382 mAh g -1 (calculated based on the positive active material) at a current density of 1A g -1, and has good cycle stability.
  • the capacity retention rate after the discharge cycle is greater than 80%.
  • the battery cell obtained through the above steps has a specific discharge capacity of about 350mAh g -1 (calculated based on the positive electrode active material) at a current density of 1A g -1 , and the capacity retention rate is greater than 70 after 200 charge-discharge cycles %.

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Abstract

一种高浓度溶液，适用于电解液，溶液中至少具有锌离子、溴离子和氯离子，通过"多盐共溶"作用，形成新的"溶盐混合物"，大大提高溶液的浓度。还提供一种超高浓度溶液，其还包含有醋酸锌，通过醋酸锌的"封端"作用，使得盐无法继续聚集生长，进而成为分子量较大的无机寡聚体稳定地存在于溶液中，其浓度甚至可以达到45mol kg -1。高浓度的电解液不仅有效地抑制了水的电解，而且降低了溴离子的氧化电位，进一步促进了溴在电池正极材料中的插层，极大地提升了正极的比容量(～638mAh g -1)。而且电解液活性离子浓度的增加，可以减少电解液的用量，有利于非摇椅式电池能量密度的提升。

Description

一种高浓度溶液及其应用与制备方法 技术领域
本发明涉及一种高浓度溶液及其在水系双离子电池中的应用，所述溶液浓度可以达到30mol kg -1以上，可以大大促进电池的比容量。
背景技术
由于近年来可再生能源技术的快速发展，电网级储能需求正在不断增长。尽管锂离子电池凭借其高能量密度的特点主导了包括便携式电子设备和电动汽车等应用在内的电化学储能市场，但是考虑到天然锂资源的自然丰度、不均匀分布，将其用于千兆瓦级别的电网储能是不太合理的，并且还会带来较高的成本问题。水系电化学储能器件不仅价格便宜，而且还具有极高的安全性，为可再生能源的大规模存储提供了一种解决方案。
然而，目前无锂电池的能量密度普遍远低于锂离子电池，这种现象在水体系中尤为明显。虽然使用“盐包水”型电解质可有效提升水系电化学储能器件的能量密度，但这类电解质大部分都基于昂贵的有机锂盐。能否使用高自然丰度的非锂元素制备出具有超高浓度的水系电解质，并发展低成本，高能量密度的无锂型水系可充电电池技术，是一个亟待解决的问题，但也面临着巨大的挑战。
发明内容
本发明的一个目的在于提供一种高浓度水溶液，适用于电解液，溶液中至少具有锌离子、溴离子和氯离子，其中，锌离子的浓度在30mol kg -1以上。具体的，该溶液至少包括溶解在水中的氯化锌、溴化锌两种溶质，溴化锌和氯化锌组成的溶液通过“多盐共溶”作用，即高浓盐溶液作为一种新的溶剂溶解另一种未水合的盐，并形成新的“溶盐混合物”，大大提高溶液的浓度，其中，所述锌离子的浓度可以达到30mol kg -1以上，浓度mol kg -1指的是每千克水所溶解的溶质的物质的量。
上述溶液中，溴化锌和氯化锌可以任意配比，通常的，溴离子的浓度范围为15～90mol kg -1,氯离子的浓度范围为15～90mol kg -1。在某些实施例中，溴离子与氯离子的浓度比为1：3，可以有效提高双体系溶液中锌离子浓度。
本发明的另一个目的在于提供一种超高浓度溶液，其还包含有醋酸根离子，具体的，含有溶质醋酸锌，进一步通过醋酸锌的“封端”作用，使得盐无法继续聚集生长，进而成为分子量较大的无机寡聚体稳定地存在于溶液中。为保持液相状态，锌离子的浓度在50mol kg -1以下，醋酸高离子的浓度在10mol kg -1以下。
通过实验证明，溴离子与氯离子的浓度比为1：3，可以有效提高三体系溶液中锌离子浓度。
本发明的另一个目的在于上述溶液在电池电解液中的应用，高浓度的电解液不仅有效地抑制了水的电解，而且降低了溴离子的氧化电位，促进了溴在电池正极材料中的插层，极大地提升了正极的比容量(～638mAh g -1)。而且电解液活性离子浓度的增加，可以减少电解液的用量，有利于非摇椅式电池能量密度的提升。
本发明的另一个目的在于上述溶液在电池电解液中的应用，高浓度的电解液实现了溴的I-阶插层从现有的单层石墨烯向宏观材料的突破(现有技术中，仅在单层石墨烯上观察到溴的I阶插层，其在宏观石墨类材料中仅能实现II阶插层，而单层石墨烯无法工业化使用)，赋予了电池正极高的比容量。
在某些实施例中，电池的正极采用碳材料，尤其是碳纳米管、天然石墨、膨胀石墨、石墨烯、石墨烯组装体及其它具有石墨晶格结构的碳材料。实施例证明，不管何种正极材料，均能实现溴离子的I阶插层。
在某些实施例中，电池的负极采用锌负极，包括金属锌、含锌合金或其它可负载锌的惰性导电基底。
本发明的另一个目的在于上述高浓度溶液的制备方法，具体如下：
将ZnCl 2，ZnBr 2和去离子水加入到容器中混合均匀，控制锌离子的浓度在35mol kg -1以下，获得氯化锌、溴化锌两种溶质的溶液。其中，在混合过程中，可以适当加热(40-100℃，2～24小时)搅拌来促进溶解。
将ZnCl 2，ZnBr 2和去离子水加入到容器中，混合后加入无水Zn(OAc) 2，搅拌均匀后置于100～120℃下加热2h以上，获得氯化锌、溴化锌、醋酸锌三种溶质的溶液。其中，在ZnCl 2，ZnBr 2的混合过程中，可以适当加热(40-100℃，2～24小时)搅拌来促进溶解。经过实验证明，三体系溶液中，锌离子的浓度在50mol kg -1以下，醋酸高离子的浓度在10mol kg -1以下，可保持液相状态，作为液相电解质使用。因此，通过Zn(OAc) 2的加入，可以获得锌离子的浓度在35～50mol kg -1的溶液。
本发明的有益效果在于：本发明杂化溶质体系具有任意单一组分不具备的性质，其在水中的溶解度远高于单一的氯化锌、溴化锌或醋酸锌。由溴化锌和氯化锌组成的双组份溶液其高浓度来源于“多盐共溶”作用，即高浓盐溶液作为一种新的溶剂溶解另一种未水合的盐，并形成新的“溶盐混合物”。而超浓氯化锌-溴化锌-醋酸锌-水“共聚物”的形成则基于另一机理：高温下溶解于水中的大量电解质盐在冷却至室温时，由于醋酸根离子的“封端”而无法继续聚集生长，进而成为分子量较大的无机寡聚体稳定地存在于电解质溶液中而非形成晶粒析出。后者的形成机理与已知的“水包盐”和“盐包水”电解质截然不同，它的发现突破了常规溶解途径所能实现的电解质浓度极限，可以被认为是“第三类水系电 解质”。上述各种超浓电解液不仅有效地抑制了水的电解，而且降低了溴离子的氧化电位，进一步促进了溴在正极材料中的插层，实现了溴在正极材料中的一阶插层，极大地提升了正极的放电比容量(～638mAh g -1)和库伦效率。得益于电解液中极高的离子浓度，组装而成的双离子电池具有高的比能量密度，且制备简单，成本低廉，在大规模固定式电网级电化学储能市场中具有重要应用前景。
本发明中，除特别说明，浓度均采用溶质溶剂比表示，60～100mol kg -1指的是每千克水所溶解的溶质的物质的量为60～100mol。
附图说明
图1为实施例1的盐-水“共聚物”质谱，从图中可以看出溶液内存在大量相对分子质量大于体系内任意组分的分子离子峰，意味着盐-水“共聚物”中寡聚体的存在。
图2为实施例1的盐-水“共聚物”电解液及其前驱体照片，从图中可以看出由摩尔比为33.75：11.25：1的氯化锌、溴化锌和醋酸锌与少量水按特定化学计量比混合加热后可以形成室温稳定的无色透明盐-水“共聚物”。
图3为实施例1的电池恒流充放电图，从图中可以看出其在1A g -1的电流密度下充放电比容量大于650mAh g -1，且库伦效率大于95％。
图4为实施例1的电池循环图，从图中可以看出其在1A g -1的电流密度下循环200圈以后容量保持率大于98％。
图5为实施例2的电解液及其前驱体照片，从图中可以看出由摩尔比为28：14：1的氯化锌、溴化锌和醋酸锌与少量水按特定化学计量比混合加热后可以形成室温稳定的无色透明盐-水“共聚物”。
图6为实施例3的水相共溶盐电解液及其前驱体照片，从图中可以看出由摩尔比为3：1的氯化锌、溴化锌与少量水按特定化学计量比混合加热后可以形成室温稳定的无色透明水相共溶盐。
图7为实施例4的盐-水“共聚物”电解液及其前驱体照片，从图中可以看出由摩尔比为22.5：22.5：1的氯化锌、溴化锌和醋酸锌与少量水按特定化学计量比混合加热后可以形成室温稳定的无色透明盐-水“共聚物”。
图8为实施例1宏观正极材料-石墨烯膜正极在盐-水“共聚物”中的电化学原位拉曼 光谱图，从中可以看到，充电过程中石墨烯的G峰位置从1579cm -1变为1625cm -1，代表着I-阶Br插层石墨化合物的形成；放电过程中G峰重新变回1579cm -1，证明了充放电过程完全可逆。
图9为实施例1宏观正极材料-石墨烯膜正极在盐-水“共聚物”中的电化学原位XRD光谱图，从中可以看到，充电过程中石墨烯的(002)面峰位置从原先的26.5°变为25.3°，代表着I-阶Br插层石墨化合物的形成；放电过程中又重新变回26.3°，证明了充放电过程完全可逆。
具体实施方式
下面通过实施例对本发明进行具体描述，本实施例只用于对本发明做进一步的说明，不能理解为对本发明保护范围的限制，本领域的技术人员根据上述发明的内容做出一些非本质的改变和调整，均属于本发明的保护范围。
实施例1：
(1)将0.3375mol氯化锌、0.1125mol溴化锌依次加入到10g去离子水中，然后置于60℃环境下加热2h，得到由ZnCl 2、ZnBr 2和水组成的白色浑浊液。加入0.01mol醋酸锌，120℃烘箱中继续加热2h，自然冷却得到总浓度为46mol kg -1的氯化锌-溴化锌-醋酸锌盐-水“共聚物”溶液，其中溴离子与氯离子的摩尔比例为1:3，见图2。
(2)将锌负极、浸润了(1)中电解液的玻纤隔膜和石墨烯膜正极依次叠加到电池模具中加压热封。
经过以上步骤得到的电池单体，在1A g -1的电流密度下，其放电比容量为607.5mAh g -1(基于正极活性物质计算，见图3),且具有优异的循环稳定性，在进行200次充放电循环后容量保持率大于98％(见图4)。
该电池充放电过程中石墨烯膜正极的原位拉曼和X-射线衍射图分别如图8和9，从中可以看到，充电过程中石墨烯的G峰位置从1579cm -1变为1625cm -1，代表着I-阶Br插层石墨化合物的形成；放电过程中G峰重新变回1579cm -1，证明了充放电过程完全可逆。根据电化学原位XRD光谱图可以看出，充电过程中石墨烯的(002)面峰位置从原先的26.5°变为25.3°，代表着I-阶Br插层石墨化合物的形成；放电过程中又重新变回26.3°，证明了充放电过程完全可逆。
根据能斯特方程：
E＝E o-RT/zF·ln(α[R]/α[O])
阴离子的氧化还原电位为：
E anion＝E o-RT/zF·ln(c[anion]/γ[anion])
电解液中总离子浓度的提升，降低了溴离子的氧化电位，提高了锌离子的还原电位，进一步避免了水分子析氧析氢副反应的发生，并有利于抑制卤素的“穿梭效应”，促进其在宏观正极材料中的插层。
结合电化学原位拉曼和X-射线衍射技术(图8～9)，证明了充电过程中溴在石墨正极中实现了I-阶插层，从而赋予了电池正极高的比容量。
实施例2：
(1)将0.28mol氯化锌、0.14mol溴化锌依次加入到10g去离子水中，然后置于40℃环境下加热24h，得到由ZnCl 2、ZnBr 2和水组成的白色浑浊液。加入0.01mol醋酸锌，100℃烘箱中继续加热10h，自然冷却得到总浓度为43mol kg -1的氯化锌-溴化锌-醋酸锌盐-水“共聚物”溶液，其中溴离子与氯离子的摩尔比例为1:2，见图5。
(2)将石墨烯纤维无纺布负极基底、浸润了(1)中电解液的玻纤隔膜和膨胀石墨正极依次叠加到电池模具中加压热封。
经过以上步骤得到的电池单体，在1A g -1的电流密度下，其放电比容量为632mAh g -1(基于正极活性物质计算),且具有较好的循环稳定性，在进行200次充放电循环后容量保持率大于90％。
对该电池充放电过程中膨胀石墨正极进行原位拉曼测试和XRD测试，并按照实施例1进行分析，证明了该浓度下溴在膨胀石墨正极中也实现了I-阶插层，从而赋予了电池正极高的比容量。
实施例3：
(1)将0.245mol氯化锌、0.245mol溴化锌依次加入到10g去离子水中，然后置于100℃环境下加热2h，得到由ZnCl 2、ZnBr 2和水组成的白色浑浊液。加入0.05mol醋酸锌，120℃烘箱中继续加热72h，自然冷却得到总浓度为50mol kg -1的氯化锌-溴化锌-醋酸锌盐-水“共聚物”溶液，其中溴离子与氯离子的摩尔比例为1:1，见图6。
(2)将碳布负极基底、浸润了(1)中电解液的玻纤隔膜和中相微球石墨正极依次叠加到电池模具中加压热封。
经过以上步骤得到的电池单体，在1A g -1的电流密度下，其放电比容量为637mAh g -1(基于正极活性物质计算),且具有较好的循环稳定性，在进行200次充放电循环后容量保持率大于85％。
对该电池充放电过程中的中相微球石墨正极进行原位拉曼测试和XRD测试，并按照实施例1进行分析，证明了该浓度下溴在中相微球石墨正极中也实现了I-阶插层，从而 赋予了电池正极高的比容量。
实施例4：
(1)将0.2625mol氯化锌和0.0875mol溴化锌依次加入到10g去离子水中，置于60℃环境下加热2h，自然冷却后得到总浓度为35mol kg -1的氯化锌-溴化锌水相共溶盐溶液，其中溴离子与氯离子的摩尔比例为1:3，见图7。
(2)将锌负极、浸润了(1)中电解液的玻纤隔膜和人造石墨正极依次叠加到电池模具中加压热封。
经过以上步骤得到的电池单体，在1A g -1的电流密度下，其放电比容量为382mAh g -1(基于正极活性物质计算),且具有较好的循环稳定性，在进行200次充放电循环后容量保持率大于80％。
实施例5：
(1)将0.225mol氯化锌、0.075mol溴化锌一起加入到10g去离子水中，置于60℃环境下加热2h，得到总浓度为30mol kg -1的氯化锌-溴化锌水相共溶盐溶液，其中溴离子与氯离子的摩尔比例为1:3。
(2)将锌负极、浸润了(1)中电解液的玻纤隔膜和沥青基石墨正极依次叠加到电池模具中加压热封。
经过以上步骤得到的电池单体，在1A g -1的电流密度下，其放电比容量约为350mAh g -1(基于正极活性物质计算),在进行200次充放电循环后容量保持率大于70％。

Claims (10)

  1. 一种高浓度溶液，其特征在于，溶液为水溶液，溶液中至少具有锌离子、溴离子和氯离子，其中，锌离子的浓度在30mol kg -1以上，浓度指的是每千克水所溶解的溶质的物质的量。
  2. 根据权利要求1所述的溶液，其特征在于，溴离子的浓度范围为15～90mol kg -1,氯离子的浓度范围为15～90mol kg -1。
  3. 根据权利要求1所述的溶液，其特征在于，溴离子与氯离子的浓度比为1：3。
  4. 根据权利要求1所述的溶液，其特征在于，还包括醋酸根离子，且锌离子的浓度在50mol kg -1以下，醋酸根离子的浓度在10mol kg -1以下。
  5. 根据权利要求4所述的溶液，其特征在于，溴离子与氯离子的浓度比为1：3。
  6. 如权利要求1～5任一项所述的溶液作为电池电解液的应用。
  7. 根据权利要求6所述的应用，其特征在于，电解液中锌离子的浓度为46mol kg -1，溴离子、氯离子、醋酸根浓度比为11.25：33.75：1。
  8. 如权利要求4所述的溶液的制备方法，其特征在于，该方法至少包括：将ZnCl 2，ZnBr 2和去离子水加入到容器中，混合后，加入无水Zn(OAc) 2，搅拌均匀后置于100～120℃下加热2h以上。
  9. 根据权利要求8所述的制备方法，其特征在于，所述溴离子的浓度范围为15～90mol kg -1,氯离子的浓度范围为15～90mol kg -1，锌离子的浓度在50mol kg -1以下，醋酸根离子的浓度在10mol kg -1以下。
  10. 根据权利要求8所述的制备方法，其特征在于，溴离子与氯离子的浓度比为1：3。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN120073092A (zh) * 2025-02-26 2025-05-30 南京工业大学 一种锌离子电池用溴化锌/溴化锂复合电解液的制备方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102479968A (zh) * 2010-11-29 2012-05-30 中国科学院大连化学物理研究所 一种锌/多卤化物储能电池
CN103094627A (zh) * 2011-11-03 2013-05-08 苏州宝时得电动工具有限公司 电池
CN105206879A (zh) * 2015-10-29 2015-12-30 中国科学院青岛生物能源与过程研究所 一种碱性锌二次电池及其制备方法
CN107112576A (zh) * 2014-10-06 2017-08-29 Eos能源储存有限责任公司 用于可充电的电化学电池的电解质
CN109524248A (zh) * 2018-12-06 2019-03-26 中国科学院兰州化学物理研究所 一种锌离子混合电容器的构筑方法
WO2020076985A1 (en) * 2018-10-10 2020-04-16 Oregon State University Aqueous zinc-metal batteries comprising "water-in-salt" electrolyte
CN111244561A (zh) * 2020-03-08 2020-06-05 南开大学 基于水系电解液的高能量密度、高电压石墨-锌基离子电池的制备方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102479968A (zh) * 2010-11-29 2012-05-30 中国科学院大连化学物理研究所 一种锌/多卤化物储能电池
CN103094627A (zh) * 2011-11-03 2013-05-08 苏州宝时得电动工具有限公司 电池
CN107112576A (zh) * 2014-10-06 2017-08-29 Eos能源储存有限责任公司 用于可充电的电化学电池的电解质
CN105206879A (zh) * 2015-10-29 2015-12-30 中国科学院青岛生物能源与过程研究所 一种碱性锌二次电池及其制备方法
WO2020076985A1 (en) * 2018-10-10 2020-04-16 Oregon State University Aqueous zinc-metal batteries comprising "water-in-salt" electrolyte
CN109524248A (zh) * 2018-12-06 2019-03-26 中国科学院兰州化学物理研究所 一种锌离子混合电容器的构筑方法
CN111244561A (zh) * 2020-03-08 2020-06-05 南开大学 基于水系电解液的高能量密度、高电压石墨-锌基离子电池的制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DONGHYEON KIM , JOONHYEON JEON: "Study on Durability and Stability of an Aqueous Electrolyte Solution for Zinc Bromide Hybrid Flow Batteries", JOURNAL OF PHYSICS: CONFERENCE SERIES, vol. 574, no. 1, 31 December 2015 (2015-12-31), pages 1 - 4, XP020277390, ISSN: 1742-6596, DOI: 10.1088/1742-6596/574/1/012074 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN120073092A (zh) * 2025-02-26 2025-05-30 南京工业大学 一种锌离子电池用溴化锌/溴化锂复合电解液的制备方法

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