Battery and electric device

Abstract

Disclosed are a battery and an electric device. The battery comprises an electrolyte solution and a negative electrode sheet, the electrolyte solution comprises sodium ions, M ions, and an ether solvent, the volume proportion of the ether solvent in the electrolyte solution is greater than or equal to 50%, and M is a metal element, and comprises one or more of potassium, lead, and mercury. The negative electrode sheet comprises flowable metallic compositions when the battery is in a fully charged state, and the metallic compositions comprise a sodium element and the M element.

Description

Batteries and electrical devices Technical Field

[0001] The present invention relates to the field of batteries, and more specifically, to batteries and electrical devices. Background Art

[0002] Batteries, as energy storage devices, are widely used in various fields. For example, they are not only widely used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also in electric vehicles such as electric bicycles, electric motorcycles, electric vehicles, and ships, as well as in military equipment and aerospace. As society develops, people's requirements for batteries are also becoming increasingly higher.

[0003] Summary of the Invention

[0004] In view of the technical problems existing in the background technology, the present application provides a battery aimed at inhibiting dendrite growth.

[0005] In order to achieve the above objectives, the first aspect of the present application provides a battery, comprising:

[0006] An electrolyte and a negative electrode plate, wherein the electrolyte includes sodium ions, M ions and an ether solvent, the volume proportion of the ether solvent in the electrolyte is ≥50%, M is a metal element and includes one or more of potassium, lead, and mercury; when the battery is fully charged, the negative electrode plate includes a fluid metal component, and the metal component includes sodium and M elements.

[0007] The battery of the present application has the following beneficial effects: ether solvents and sodium metal have good compatibility, and the use of the electrolyte of the given composition is conducive to the reduction and deposition of sodium ions and M ions at the negative electrode during the charging process to form a mobile metal component, thereby fundamentally inhibiting the growth of dendrites and reducing the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle.

[0008] In some embodiments of the present application, the molar ratio of the M ions in the electrolyte is ≤ 50%, based on the total molar number of the sodium ions and the M ions. This is beneficial for achieving a better effect of inhibiting dendrite growth and improving the operability of the battery during the production process.

[0009] In some embodiments of the present application, the molar ratio of the M ions in the electrolyte is ≤ 20%, based on the total molar number of the sodium ions and the M ions. This effectively inhibits dendrite growth while further reducing the fluidity of the electrode material and improving the operability of the battery during production.

[0010] In some embodiments of the present application, in the electrolyte, the total molar concentration of sodium ions and M ions is 0.6 mol / L to 2.5 mol / L.

[0011] In some embodiments of the present application, the volume proportion of the ether solvent in the electrolyte is ≥ 80%. This further facilitates the reduction and deposition of sodium and M ions at the negative electrode to form mobile metal components, thereby achieving improved cycle life and interfacial stability.

[0012] In some embodiments of the present application, the ether solvent includes a halogen-substituted and / or unsubstituted ether solvent.

[0013] In some embodiments of the present application, the unsubstituted ether solvent includes one or more of dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, pentaethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, pentaethylene glycol diethyl ether, diethylene glycol dibutyl ether, tetrahydrofuran, and dioxolane.

[0014] In some embodiments of the present application, the halogen-substituted ether solvent includes one or more of methyl nonafluoro-n-butyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, and octafluoropentyl-tetrafluoroethyl ether.

[0015] In some embodiments of the present application, the negative electrode plate includes a metal foil.

[0016] In some embodiments of the present application, the metal foil includes: a substrate and a surface modification layer provided on at least one side of the substrate.

[0017] In some embodiments of the present application, the surface modification layer includes a conductive agent, which is beneficial for promoting the directional and orderly deposition of sodium ions and M ions on the surface of the negative electrode, and improving the deposition morphology and distribution uniformity of the mobile metal components on the surface of the negative electrode.

[0018] In some embodiments of the present application, the surface modification layer includes a conductive carbon material and a binder, and the binder accounts for 10 wt % to 95 wt % of the surface modification layer.

[0019] In some embodiments of the present application, the binder includes one or more of styrene-butadiene copolymer, acrylate-styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-styrene copolymer, acrylic rubber, butyl rubber, styrene-butadiene rubber, fluororubber, polyethylene, polypropylene, EPDM rubber, EPDM rubber, polyethylene oxide, polyepichlorohydrin, polyvinyl pyrrolidone, polyphosphazene, polyacrylonitrile, polystyrene, polyvinyl pyridine, chlorosulfonated polyethylene, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, hydroxypropyl methylcellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polytetrafluoroethylene, polyacrylic acid, polyimide, polyamideimide, polyimide-polyamideimide copolymer, sodium carboxymethyl cellulose, sodium alginate, and / or derivatives of one or more thereof.

[0020] In some embodiments of the present application, the binder includes hydroxyl and / or carboxyl groups. This can promote the desolvation of sodium ions during deposition on the negative electrode sheet, improve the deposition morphology and distribution uniformity of the formed mobile metal component on the surface of the negative electrode sheet, and further help to inhibit dendrite formation and reduce the risk of separator puncture.

[0021] In some embodiments of the present application, the binder includes one or more of sodium carboxymethyl cellulose, sodium alginate and polyacrylic acid.

[0022] The second aspect of the present application provides an electrical device, comprising: the battery of the first aspect of the present application.

[0023] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] FIG1 is a schematic structural diagram of a battery according to one embodiment of the present application.

[0026] FIG2 is a schematic structural diagram of a battery module according to an embodiment of the present application.

[0027] FIG3 is a schematic structural diagram of a battery pack according to an embodiment of the present application.

[0028] FIG4 is an exploded view of a battery pack according to an embodiment of the present application.

[0029] FIG5 is a schematic diagram of an electric device using a battery as a power source according to an embodiment of the present application.

[0030] FIG6 is a scanning electron microscope image of the side of the diaphragm facing the negative electrode sheet obtained by disassembling the battery prepared according to Example 1 of the present application after 100 charge and discharge cycles in the charged state.

[0031] FIG7 is a scanning electron microscope image of the side of the diaphragm facing the negative electrode sheet obtained by disassembling the battery prepared in Comparative Example 2 of the present application after an internal short circuit occurs.

[0032] Figure 8 is a voltage difference curve corresponding to different charge states calculated based on the formation stage charging curves collected in Example 1 and Comparative Example 1 of the present application, wherein the right figure in Figure 8 is a partial enlarged view of the left figure.

[0033] Description of reference numerals:

[0034] 1: Battery; 2: Battery module; 3: Battery pack; 4: Upper case; 5: Lower case. DETAILED DESCRIPTION

[0035] The present application will be further described below in conjunction with specific embodiments. It should be understood that these specific embodiments are only used to illustrate the present application and are not used to limit the scope of the present application.

[0036] Below, with appropriate reference to the accompanying drawings, the embodiments of the positive electrode active material and its preparation method, the positive electrode sheet, the battery and the electric device of the present application are described in detail. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structure are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0037] The "range" disclosed in this application is defined in the form of a lower limit and / or an upper limit, and a given range is defined by selecting a lower limit and / or an upper limit, and the selected lower limit and / or upper limit define the boundaries of a particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form an unspecified range, and any lower limit can be combined with other lower limits to form an unspecified range, and similarly any upper limit can be combined with any other upper limit to form an unspecified range. In addition, each separately disclosed point or single value itself can be combined with any other point or single value as a lower limit or upper limit or with other lower limits or upper limits to form an unspecified range. For example, if a range of 60 to 120 and 80 to 110 is listed for a particular parameter, it is understood that a range of 60 to 110 and 80 to 120 is also contemplated. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4, and 5 are listed, the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise specified, the numerical range "a-b" is an abbreviation for any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed in this document, and "0-5" is just an abbreviation for these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0038] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present application.

[0039] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form new technical solutions, and such technical solutions should be deemed to be included in the disclosure of this application.

[0040] Unless otherwise specified, all steps of the present application can be performed sequentially or randomly, preferably sequentially.

[0041] Unless otherwise specified, the term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0042] In this application, the terms "plurality" and "multiple" refer to two or more.

[0043] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned description of the drawings and any variations thereof are intended to cover non-exclusive inclusions. Unless otherwise specified, the terms used in this application have the well-known meanings commonly understood by those skilled in the art. Unless otherwise specified, the numerical values ​​of the parameters mentioned in this application can be measured using various measurement methods commonly used in the art (for example, they can be tested according to the methods given in the examples of this application).

[0044] With the continuous advancement of the theme of green environmental protection, the application of batteries has penetrated into all aspects of life, including vehicles, electronic equipment, energy storage devices, etc. However, with the continuous promotion of battery applications, people's requirements for batteries are getting higher and higher. Taking sodium batteries as an example, especially sodium batteries that directly use metal foil as the negative electrode plate, they face the problem of negative electrode dendrite growth during the cycle, which causes the dendrites to pierce the isolation membrane and cause internal short circuits. At present, related fields usually adopt methods such as increasing the strength of the isolation membrane, constructing SEI film, or modifying the negative electrode plate to induce orderly deposition of sodium ions, and solid-state battery design to reduce the risk of dendrites piercing the diaphragm.

[0045] In the present application, the battery adopts an electrolyte including sodium ions, M ions and ether solvents, and the volume proportion of ether solvents in the electrolyte is ≥50%, M is a metal element including one or more of potassium, lead, and mercury, and the battery includes a fluid metal component on the negative electrode plate when fully charged, and the metal component contains sodium and M elements. This can fundamentally inhibit the growth of dendrites and reduce the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle.

[0046] The battery disclosed in the embodiments of the present application can be used in electrical devices that use the battery as a power source or various energy storage systems that use the battery as an energy storage element. Electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery cars, electric cars, ships, spacecraft, and the like. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like, and spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0047] The first aspect of the present application provides a battery comprising: an electrolyte and a negative electrode plate, the electrolyte comprising sodium ions, M ions and an ether solvent, the volume proportion of the ether solvent in the electrolyte being ≥50%, M being a metal element and comprising one or more of potassium, lead, and mercury; when the battery is fully charged, the negative electrode plate comprises a metal component with fluidity, and the metal component comprises sodium and M elements.

[0048] The term "fully charged state" refers to the state in which the battery, after being charged to the upper operating voltage, does not change its SOC value at a charging current of 0.05C. The operating voltage of the battery is limited by the type of positive electrode active material or selected according to standard battery parameters. Furthermore, the volume percentage of the ether solvent in the electrolyte can be 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.8%, 99.9%, 100%, or any range thereof. Among them, whether there is an ether solvent in the electrolyte and the volume ratio of the ether solvent in the electrolyte can be obtained in combination with conventional detection methods and instruments in the field, such as gas chromatography, gas chromatography-mass spectrometry, liquid chromatography and other testing methods. Whether there are Na ions and M ions in the electrolyte can also be obtained in combination with conventional detection methods and instruments in the field, such as atomic absorption spectrometry (AAS), inductively coupled plasma optical emission spectrometry (ICP-OES) and other methods. In addition, the electrolyte can be tested at room temperature (25 ° C) under a vacuum environment (the vacuum degree can be 10 -6 Pa or less, such as 10 -6 Pa~10 -8 Pa) The fully charged battery is disassembled and transferred to observe whether there is a mobile metal component on the surface of the negative electrode (the instruments used in the observation process include but are not limited to atomic force microscopy, etc.). In addition, the elemental composition of the metal component can also be obtained by combining conventional detection methods and instrument tests in this field, such as including but not limited to one or more of XPS half-charge characterization, AAS method, ICP-OES method, etc.

[0049] In the electrolyte, for sodium ions and M ions, the composition of the solvent and the content of ether solvents will affect the deposition effect of sodium ions and M ions on the negative electrode sheet, and the deposition effect will affect the performance of the battery, such as cycle life. Taking ether solvents and ester solvents as examples, ether solvents have relatively good compatibility with sodium metal and good reduction resistance. Compared with batteries configured with ester solvents as electrolyte solvents, batteries configured with electrolytes containing ether solvents and with the volume ratio of ether solvents meeting the given range can achieve the reduction of sodium ions and M ions at the negative electrode during charging. And deposited to form a metal component with fluidity. The metal component with fluidity usually exists in liquid form and has a certain surface tension. Compared with dendrites, it does not form sharp edges and corners, and the risk of piercing the diaphragm after contact with the diaphragm is lower; and, affected by the composition, fluidity and surface tension of the metal component, the metal component with fluidity is easy to form on the side of the negative electrode sheet close to the separator, and can cover the surface of the negative electrode sheet, reducing the area of ​​the region where dendrites may form on the surface of the negative electrode sheet, thereby further reducing the risk of dendrites piercing the diaphragm. In summary, the growth of dendrites can be fundamentally suppressed, and an improved cycle life can be obtained. In addition, the use of ether solvents is also beneficial to improving the interface stability of the negative electrode, such as improving the interface stability of the metal negative electrode.

[0050] The battery of the present application has the following beneficial effects: ether solvents and sodium metal have good compatibility, and the use of the electrolyte of the given composition is conducive to the reduction and deposition of sodium ions and M ions at the negative electrode during the charging process to form mobile metal particles, thereby fundamentally inhibiting the growth of dendrites and reducing the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle.

[0051] Furthermore, the battery of the first aspect of the present application may optionally meet one or more of the following conditions on the basis of meeting the above conditions.

[0052] In some embodiments of the present application, when the battery is in a fully charged state, the fluid metal component included on the negative electrode plate may include a liquid alloy. In the charged state, sodium ions and M ions can be reduced and deposited on the negative electrode plate to form metallic sodium and metallic M, and when metallic sodium comes into contact with metallic potassium, lead or mercury, an alloying reaction easily occurs to form a liquid alloy. For example, taking potassium as an example, metallic sodium and metallic potassium can form a liquid sodium-potassium alloy when they come into contact. In addition to being fluid, the liquid alloy formed by metallic sodium and metallic M also has good surface tension, which is beneficial to further improve the coverage and distribution uniformity of the fluid metal component on the surface of the negative electrode plate, and further helps to fundamentally inhibit the growth of dendrites and reduce the risk of internal short circuits caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle. Optionally, M can be potassium.

[0053] In some embodiments of the present application, in the electrolyte, based on the total molar number of sodium ions and M ions, the molar ratio of M ions may be ≤50%.

[0054] For example, based on the total molar number of sodium ions and M ions, the molar proportion of M ions can be 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, etc., or can be a range consisting of any of the above values. The content of sodium ions and M ions in the electrolyte can be quantitatively analyzed by atomic absorption spectrometry or inductively coupled plasma optical emission spectrometry, and the molar proportion of M ions can be calculated based on the quantitative analysis results. The relative amounts of M ions and sodium ions will affect their reduction deposition on the negative electrode sheet, as well as the content and formation efficiency of the mobile metal components formed. During the charging process, the formation of a small amount of mobile metal components on the surface of the negative electrode sheet can effectively inhibit the formation and growth of dendrites while taking into account good electrochemical performance. Among them, reducing the content of mobile metal components is beneficial to reducing the fluidity of the electrode material and improving the operability during the battery production process. For sodium batteries, ensuring that the content of M ions meets the given range is also beneficial to reducing the internal resistance of the battery and improving the performance and efficiency of the battery. Increasing the content of mobile metal components is beneficial to increasing its coverage on the surface of the negative electrode sheet and reducing the risk area of ​​dendrite formation on the negative electrode sheet.

[0055] Therefore, ensuring that the content of M ions meets the given range is beneficial for achieving a better effect of inhibiting dendrite growth and reducing the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle, while also taking into account the electrochemical properties of the battery and improving the operability of the battery during the production process.

[0056] In some embodiments of the present application, the molar proportion of M ions in the electrolyte can be ≤20%, based on the total molar number of sodium ions and M ions. By further adjusting the M ion content to meet the given range, the battery can achieve better electrochemical performance while effectively suppressing dendrite growth, further reducing the fluidity of the electrode material, and improving the operability of the battery during the production process.

[0057] In some embodiments of the present application, the total molar concentration of sodium ions and M ions in the electrolyte can be 0.6 mol / L to 2.5 mol / L. For example, it can be 0.6 mol / L, 0.8 mol / L, 1 mol / L, 1.2 mol / L, 1.5 mol / L, 1.8 mol / L, 2 mol / L, 2.2 mol / L, 2.5 mol / L, etc., or it can be a range consisting of any of the above values. The total molar concentration of sodium ions and M ions in the electrolyte can also be quantitatively analyzed by atomic absorption spectrometry or inductively coupled plasma optical emission spectrometry. The concentrations of M ions and sodium ions in the electrolyte will also affect their reduction deposition on the negative electrode sheet, as well as the content and formation efficiency of the mobile metal components formed. Making the concentrations of the two meet the given range is beneficial to taking into account the coverage of the mobile metal components on the surface of the negative electrode sheet, the fluidity of the metal components, and the electrochemical performance of the battery during the charging process. This is conducive to achieving a better effect of inhibiting dendrite growth, reducing the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle, and improving the operability of the battery during the production process.

[0058] In some embodiments of the present application, the volume proportion of the ether solvent in the electrolyte may be ≥80%.

[0059] For example, the volume percentage of the ether solvent in the electrolyte can be 80%, 82%, 85%, 88%, 90%, 92%, 95%, 98%, 100%, etc., or can be a range consisting of any of the above values. Increasing the volume content of the ether solvent in the electrolyte not only helps to further improve the compatibility of the solvent and sodium metal, but also enables better reduction and deposition of sodium ions and M ions at the negative electrode during charging to form a mobile metal component, such as a liquid alloy, thereby achieving an improved cycle life, and further helps to further improve the interfacial stability of the negative electrode.

[0060] This not only helps to further inhibit the growth of dendrites and reduce the risk of internal short circuit caused by dendrite growth piercing the diaphragm during the battery charge and discharge cycle, but also helps to improve the cycle life of the battery.

[0061] In some embodiments of the present application, the ether solvent may include a halogen-substituted and / or unsubstituted ether solvent.

[0062] The ether solvents used in the electrolyte may include ether solvents that are not substituted by substituents, and may also include ether solvents containing halogen substitutions. Among them, the type of ether solvent in the electrolyte can be obtained in combination with conventional detection methods and instruments in the field, such as one or more of the test methods such as gas chromatography, gas chromatography-mass spectrometry, and liquid chromatography. Ether solvents are beneficial to improving the interfacial stability of the negative electrode, and halogen-substituted ether solvents are beneficial to further improving the interfacial stability of the negative electrode. Thus, it is beneficial to further improve the electrochemical performance of the battery. It is understandable that the substituents carried in the halogen-substituted ether solvents may include but are not limited to halogen substituents. Alternatively, the halogen substitution may include but is not limited to fluorine substitution, wherein fluorine-substituted ether solvents are beneficial to further improve the interfacial stability of the negative electrode.

[0063] In some embodiments of the present application, the unsubstituted ether solvent may include one or more of dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, pentaethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, pentaethylene glycol diethyl ether, diethylene glycol dibutyl ether, tetrahydrofuran, and dioxolane. The above-mentioned ether solvents have good compatibility with sodium metal, and can not only better achieve the reduction and deposition of sodium ions and M ions at the negative electrode during charging to form a metal component with mobility, thereby obtaining an improved cycle life, but also improve the interfacial stability of the negative electrode.

[0064] In some embodiments of the present application, the halogen-substituted ether solvent may include one or more of methyl nonafluoro-n-butyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, and octafluoropentyl-tetrafluoroethyl ether. These fluorine-substituted ether solvents have good compatibility with sodium metal, enabling not only the reduction and deposition of sodium and M ions at the negative electrode during charging to form mobile metal components, thereby improving cycle life, but also further improving the interfacial stability of the negative electrode.

[0065] In some embodiments of the present application, the organic solvent used in the electrolyte can be all ether solvents or a combination of ether solvents and other solvents, as long as the volume ratio of the ether solvent in the electrolyte meets the given range. Wherein, the other solvents may include but are not limited to ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), butylene carbonate (BC), fluoroethylene carbonate (FEC), methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB), ethyl butyrate (EB), 1,4-butyrolactone (GBL), cyclopentane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS), diethyl sulfone (ESE), and one or more of dimethoxymethane (DMM).

[0066] In some embodiments of the present application, the sodium ions and M ions in the electrolyte can be provided by sodium salts and M salts, and the sodium salts may include but are not limited to sodium hexafluorophosphate (NaPF6), sodium tetrafluoroborate (NaBF4), sodium perchlorate (NaIO4), sodium hexafluoroarsenate (NaAsF6), sodium bis(fluorosulfonyl)imide (NaFSI), sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), sodium trifluoromethanesulfonate (NaTFS), sodium difluorooxalatoborate (NaDFOB), sodium dioxalatoborate (NaBOB), sodium difluorophosphate (NaPO2F2), sodium difluorobis(oxalatophosphate) (NaDFOP) and sodium tetrafluorooxalatophosphate (NaTFOP). The anions of the M salts may include but are not limited to one or more of the anions mentioned above for the sodium salts. It is understood that the anions of the M salts may be the same as or different from the anions of the sodium salts. For example, taking the sodium salt as NaPF6 and the M salt as a potassium salt as an example, the potassium salt may be KPF6, KFSI, KTFSI, etc. Optionally, when the M salt is a potassium salt, it may include KPF6, PF6 - The compatibility with the negative electrode is relatively good.

[0067] In some embodiments of the present application, the battery may be a negative electrode-free battery. Compared with the conventional structure including a negative electrode current collector and a negative electrode active material layer provided on at least one side of the negative electrode current collector, in the battery of the present application, the negative electrode pole piece may be a metal foil or a composite current collector. It is understandable that the surface of the metal foil or composite current collector does not contain a negative electrode active material layer. As a result, it is beneficial to significantly improve the energy density of the battery. Among them, the metal foil may be a conventional metal foil that can be used as a negative electrode current collector, and the composite current collector may be a conventional composite current collector (for example, a metal material may be provided on a polymer substrate to form a composite current collector).

[0068] In some embodiments of the present application, the negative electrode plate may include a metal foil, that is, a metal foil may be used as the negative electrode plate. For example, the metal foil may be copper foil.

[0069] In some embodiments of the present application, the metal foil used as the negative electrode plate may include: a substrate and a surface modification layer provided on at least one side of the substrate. The surface modification layer is used to improve the performance of the battery. Exemplarily, the purpose of providing the surface modification layer may include improving the conductivity of the negative electrode plate, improving the interface stability of the negative electrode plate, promoting the directional and / or orderly deposition of sodium ions and M ions on the surface of the negative electrode plate, improving the deposition morphology (such as density, coverage, etc.) and distribution of metal components with fluidity on the negative electrode plate, and thereby improving the performance of the battery. Among them, the presence of a surface modification layer can be determined by disassembling the discharged battery and characterizing the obtained negative electrode plate structure and / or surface composition. In addition, the composition and thickness of the surface modification layer can be flexibly selected according to actual conditions such as the actual battery type and design requirements.

[0070] In some embodiments of the present application, the surface modification layer may include a conductive agent. Wherein, the presence of a conductive agent in the surface modification layer can be determined by conventional testing methods and instruments in the art. Introducing a conductive agent into the surface modification layer is beneficial to promoting the directional and orderly deposition of sodium ions and M ions on the surface of the negative electrode, improving the deposition morphology and distribution uniformity of the metal components with fluidity on the surface of the negative electrode, and is beneficial to further inhibiting the growth of dendrites, reducing the risk of the isolation membrane being punctured, and improving the electrochemical performance of the battery and extending the cycle life. Wherein, the conductive agent can be flexibly selected according to actual needs, for example, it can include but is not limited to conductive carbon materials.

[0071] In some embodiments of the present application, the surface modification layer may include a conductive carbon material and a binder, and the binder may account for 10 wt % to 95 wt % of the surface modification layer.

[0072] For example, the mass proportion of the binder in the surface modification layer can be 10wt%, 15wt%, 20wt%, 30wt%, 40wt%, 50wt%, 60wt%, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt%, etc., or can be a range consisting of any of the above values. The specific surface area of ​​the conductive carbon material is relatively large, and increasing the content of the binder is beneficial to improving the processability of the negative electrode plate and improving the adhesion and structural stability of the surface modification layer on the substrate; and increasing the content of the conductive carbon material is beneficial to increasing the exposed area of ​​the conductive carbon material, which is beneficial to regulating and promoting the directional and orderly deposition of sodium ions and M ions on the surface of the negative electrode plate, improving electronic conduction, and further improving the deposition morphology and distribution uniformity of the mobile metal components on the surface of the negative electrode plate.

[0073] Controlling the binder content in the surface modification layer to within the specified range further inhibits dendrite growth, reduces the risk of separator puncture, and improves the battery's electrochemical performance and cycle life. Alternatively, the binder content in the surface modification layer can range from 20 wt% to 95 wt%.

[0074] In some embodiments of the present application, the binder in the surface modification layer may include one or more of styrene-butadiene copolymer, acrylate-styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-styrene copolymer, acrylic rubber, butyl rubber, styrene-butadiene rubber, fluororubber, polyethylene, polypropylene, EPDM rubber, EPDM rubber, polyethylene oxide, polyepichlorohydrin, polyvinyl pyrrolidone, polyphosphazene, polyacrylonitrile, polystyrene, polyvinyl pyridine, chlorosulfonated polyethylene, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, hydroxypropyl methylcellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polytetrafluoroethylene, polyacrylic acid, polyimide, polyamideimide, polyimide-polyamideimide copolymer, sodium carboxymethyl cellulose, sodium alginate, and / or derivatives of one or more thereof. Among them, one or more derivatives of the polymers in the given range include but are not limited to polymers partially or fully substituted by alkali metals. Selecting polymers partially or fully substituted by alkali metals can reduce the risk of unsubstituted functional groups in the polymer used as a binder being gradually replaced during the use of the battery, which may lead to a certain amount of sodium loss.

[0075] In some embodiments of the present application, the binder may include hydroxyl and / or carboxyl groups. The hydroxyl and / or carboxyl groups have a strong interaction with sodium ions, which is beneficial to promote the desolvation of sodium ions during the charging process, improve the deposition morphology distribution of sodium ions on the negative electrode, and further improve the deposition morphology and distribution uniformity of the formed metal component with fluidity on the surface of the negative electrode, which is beneficial to further inhibit the growth of dendrites, reduce the risk of puncture of the isolation membrane, and improve the electrochemical performance of the battery and extend the cycle life. Among them, conventional testing methods and instruments in the field can be used to determine whether the binder in the surface modification layer includes hydroxyl and / or carboxyl groups, for example, including but not limited to infrared characterization methods.

[0076] In some embodiments of the present application, the binder used in the surface modification layer may include one or more of sodium carboxymethyl cellulose, sodium alginate, and polyacrylic acid. The binder can promote the desolvation of sodium ions during deposition on the negative electrode sheet, improving the deposition morphology and distribution of sodium ions on the negative electrode sheet. This can further improve the deposition morphology and distribution uniformity of the formed mobile metal component on the surface of the negative electrode sheet, thereby further suppressing dendrite formation and reducing the risk of separator puncture.

[0077] In some embodiments of the present application, the battery may be a secondary battery, that is, a battery that can be recharged after discharge to activate the active material and continue to be used. Optionally, the battery may be a sodium battery.

[0078] Typically, a battery also includes a positive electrode sheet and a separator. During the battery's charge and discharge process, active ions are embedded and released back and forth between the positive electrode sheet and the negative electrode sheet. The separator is arranged between the positive electrode sheet and the negative electrode sheet to serve as an isolation. Among them, the raw material composition and structure of the positive electrode sheet, the material and structural characteristics of the separator, etc. can all be conventional choices in the field. The embodiments of the present application do not have any particular restrictions on the type of battery, which may include but is not limited to sodium batteries.

[0079] Optionally, in some embodiments, the positive electrode sheet generally includes a positive electrode current collector and a positive electrode active material layer provided on the positive electrode current collector, and the positive electrode active material layer may include a positive electrode active material. The positive electrode current collector may be a conventional metal foil or a composite current collector (a metal material may be provided on a polymer substrate to form a composite current collector). As an example, the positive electrode current collector may include at least one of copper foil, aluminum foil, nickel foil, stainless steel foil, stainless steel mesh and carbon-coated aluminum foil, and aluminum foil may be optionally used. The positive electrode active material may be a positive electrode active material conventionally used in the art, and the specific type may be flexibly selected according to the battery type. In addition, conductive agents such as carbon black, acetylene black, or binders such as polyvinylidene fluoride and polyethylene oxide may be appropriately added to the positive electrode active material layer, and other optional additives may be optionally included, and the positive electrode slurry may be prepared and coated on the positive electrode current collector.

[0080] Optionally, in some embodiments, the isolation membrane can be selected from any well-known porous structure membrane with electrochemical stability and mechanical stability according to actual needs, for example, it can include but is not limited to a single-layer or multi-layer film containing at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. Optionally, the surface of the porous structure membrane can also be coated with an insulating ceramic coating, and the insulating ceramic coating can include but is not limited to alumina and / or boehmite, etc.

[0081] In addition, the embodiment of the present application has no particular limitation on the shape of the battery, which can be cylindrical, square or any other shape. FIG1 shows a square battery 1 as an example.

[0082] In some embodiments, the battery may include an outer packaging for encapsulating the positive electrode sheet, the negative electrode sheet, and the electrolyte.

[0083] In some embodiments, the outer packaging may include a housing and a cover. The housing may include a bottom plate and side plates connected to the bottom plate, with the bottom plate and side plates enclosing a receiving cavity. The housing may have an opening communicating with the receiving cavity, and the cover may be positioned over the opening to seal the receiving cavity.

[0084] The positive electrode sheet, negative electrode sheet, and separator can be wound or laminated to form an electrode assembly. The electrode assembly is encapsulated in the housing. The number of electrode assemblies in a battery can include one or more, which can be adjusted according to needs.

[0085] In some embodiments, the outer packaging of the battery may include a hard shell, such as a hard plastic shell, an aluminum shell, or a steel shell.

[0086] The outer packaging of the battery may also include a soft bag, such as a bag-type soft bag. The material of the soft bag may be plastic, such as at least one of polypropylene (PP), polybutylene terephthalate (PBT), and polybutylene succinate (PBS).

[0087] In some embodiments, the battery may be either a single battery cell or a battery module or battery pack assembled from battery cells. The battery module or battery pack may contain multiple batteries, and the specific number may be adjusted according to the application and capacity of the battery module.

[0088] Figure 2 shows an example battery module 2. Referring to Figure 2 , within the battery module 2, multiple batteries 1 may be arranged sequentially along the length of the battery module 2. Of course, any other arrangement is also possible. Furthermore, the multiple batteries 1 may be secured together using fasteners.

[0089] The battery module 2 may further include a housing having a housing space, wherein the housing space accommodates a plurality of batteries 1. In some embodiments, the battery modules may be assembled into a battery pack, and the number of battery modules contained in the battery pack may be adjusted according to the application and capacity of the battery pack.

[0090] Figures 3 and 4 illustrate an example battery pack 3. Referring to Figures 3 and 4 , the battery pack 3 may include a battery box and multiple battery modules 2 disposed within the battery box. The battery box comprises an upper case 4 and a lower case 5. The upper case 4 can be placed over the lower case 5 to form an enclosed space for accommodating the battery modules 2. The multiple battery modules 2 can be arranged in any manner within the battery box.

[0091] The second aspect of the present application provides an electrical device, which includes: the battery of the second aspect of the present application.

[0092] Specifically, the battery can serve as a power source or an energy storage unit for the electrical device. The electrical device may include, but is not limited to, mobile devices (e.g., mobile phones, laptops), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks), electric trains, ships, satellites, and energy storage systems.

[0093] Figure 5 shows an example of an electrical device. This device may include a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. Another example of an electrical device may include a mobile phone, a tablet computer, or a laptop computer. These devices are typically lightweight and thin, and may use batteries as a power source.

[0094] Below, the embodiment of the present application is described. The embodiment described below is exemplary and is only used to explain the present application, and is not to be construed as limiting the present application. Where specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. Reagents or instruments used that do not specify the manufacturer are conventional products that can be obtained commercially.

[0095] Example 1

[0096] 1. Preparation of secondary batteries

[0097] Positive electrode preparation:

[0098] Na4Fe3(PO4)2(P2O7), conductive carbon black (Super P), and polyvinylidene fluoride (PVDF) were mixed in a 90:5:5 mass ratio in N-methylpyrrolidone (NMP), stirred, and dispersed to form a positive electrode active slurry. The positive electrode active slurry was then coated on one side of aluminum foil at a surface density of 20g / cm2. After coating, the positive electrode sheets were dried, cold pressed, and slit.

[0099] Negative electrode preparation:

[0100] Conductive agent carbon nanotubes (CNT) and binder sodium carboxymethyl cellulose (CMC) were prepared by fully stirring and mixing in an appropriate amount of solvent deionized water at a weight ratio of 80:20 to form an interface modification layer slurry. The slurry was coated on the surface of one side of the copper foil, and the coating surface density was controlled to be 0.3 mg / cm 2 After coating is completed, drying, cold pressing, slitting and preparing the negative electrode sheet with the interface modification layer are performed.

[0101] Isolation membrane: PE porous polymer film with a thickness of 20μm.

[0102] Prepare electrolyte:

[0103] The composition includes: an organic solvent and an electrolyte, the organic solvent is dimethyl ether (DME), the electrolyte is sodium hexafluorophosphate (NaPF6) and potassium bis(fluorosulfonyl)imide (KFSI), and the concentrations of NaPF6 and KFSI in the electrolyte are both 0.5 mol / L.

[0104] The positive electrode sheet, separator, and negative electrode sheet are stacked in order, with the separator positioned between the positive and negative electrode sheets to form an electrode assembly. The electrode assembly is then placed in a pre-designed aluminum-plastic bag housing, and electrolyte is added to the housing to form a button cell. No formation is performed.

[0105] Examples 2 to 9 and Comparative Examples 1 to 3

[0106] The differences between Examples 2 to 9 and Comparative Examples 1 to 3 and Example 1 are shown in Table 1.

[0107] Performance testing:

[0108] 1) First charging test

[0109] At 25°C, the secondary battery was first charged to 3.65V at a constant current of 0.33C. Further, the battery was charged at a constant voltage of 3.65V to a current of 0.05C. The initial formation charge curve was collected to observe the potential differences corresponding to different SOCs (States of Charge) during the charging process. The specific operation included calculating the voltage differences corresponding to different SOCs (States of Charge) during the collected charge curves, with the total charge capacity as 100% SOC and 0.5% SOC as intervals. This yielded the voltage differences corresponding to different SOCs during the charging process between the embodiment and comparative example 1.

[0110] 2) Cyclic performance test

[0111] At 25°C, after the battery is formed, it is first discharged at a constant current of 0.33C to the lower cut-off voltage; then the secondary battery is charged to 3.65V at a constant current of 0.33C, and then charged at a constant voltage of 3.65V to a current of 0.05C; then discharged to the lower cut-off voltage at a constant current of 0.33C, and the discharge capacity at this time is recorded as C0; then, the secondary battery is charged to 3.65V at a constant current of 0.33C, and charged at a constant voltage of 3.65V to a current of 0.05C, and then discharged to the lower cut-off voltage at a constant current of 0.33C, and this cycle is repeated for n times to observe whether the secondary battery has an internal short circuit during the cycle. Among them, after n cycles, the discharge capacity of the nth cycle is recorded as C n , based on the formula: C n / C0×100%, calculate the cycle capacity retention rate of the nth cycle.

[0112] 3) Surface state of the negative electrode after charging

[0113] After the cycle performance test, the battery with internal short circuit was disassembled in a vacuum glove box at 25°C to obtain the diaphragm; for the battery without internal short circuit, the secondary battery was first charged to 3.65V at a constant current of 0.33C at 25°C, and then charged to a current of 0.05C at a constant voltage of 3.65V. The battery was then disassembled in a vacuum glove box at 25°C, and the obtained diaphragm was transferred under vacuum conditions to observe the surface morphology of the diaphragm facing the negative electrode.

[0114] Relevant tests were performed on the batteries of Examples 1 to 9 and Comparative Examples 1 to 3. The test results are shown in Table 1 and Figures 6 to 8.

[0115] Conclusion: Based on Examples 1 to 9 and Comparative Examples 1 to 3, Table 1, and Figures 6 to 8, it can be seen that during the charging process of the batteries of the above embodiments of the present application, less adhesive is formed on the side of the diaphragm facing the negative electrode plate, and only a small amount of adhesive can be observed on the surface. Passivation particles with metallic luster and spherical shape are observed, and there is no dendrite as a whole. This shows that during the charging process of the batteries of the above embodiments of the present application, a metal component with a certain coverage is formed on the surface of the negative electrode plate, and the metal component has a certain fluidity or surface tension. Compared with the sodium deposition formed in Comparative Example 1, the risk area of ​​dendrites and the risk of dendrite formation are significantly reduced. For example, taking Example 1 and Comparative Example 2 as examples, Figure 6 shows a scanning electron microscope image of the side of the diaphragm facing the negative electrode plate obtained by disassembling the battery prepared in Example 1 after 100 charge and discharge cycles in the charging state. Figure 7 shows the battery prepared in Comparative Example 2 after an internal short circuit occurs. The scanning electron microscope image of the side of the diaphragm facing the negative electrode sheet obtained by disassembly is shown in Figure 6. As can be seen from Figure 6, the battery in Example 1 was charged again after 100 cycles. After charging, there was only a small amount of adhesive on the side of the diaphragm surface facing the negative electrode sheet, and passivation particles with a metallic luster and spherical shape were clearly observed, and no dendrites were observed, indicating that a metal component with a certain fluidity or surface tension was formed on the surface of the negative electrode sheet (analysis may be the formation of a sodium-potassium liquid alloy). The surface of the metal component with a certain fluidity or surface tension is not easy to form sharp edges and corners, and the risk of puncturing the diaphragm is relatively small. As can be seen from Figure 7, when the battery in Comparative Example 2 was short-circuited, a large number of dendrites were found on the side of the diaphragm surface facing the negative electrode sheet, and no passivation particles with a metallic luster were observed. This indicates that a large number of dendrites were formed on the negative electrode sheet of Comparative Example 2, and compared with Example 1, the risk of puncturing the diaphragm in Comparative Example 2 is greater. In addition, the battery of the above embodiment of the present application has a voltage difference compared with the formation curve of comparative example 1 in the late stage of the formation process. In the late stage of charging, the voltage corresponding to the battery in the embodiment at the same SOC is slightly higher, and the voltage difference peak between the embodiment and the comparative example is located at the end of charging, indicating that sodium ions are preferentially deposited in the embodiment. For example, taking embodiment 1 as an example, FIG8 shows the voltage difference curves corresponding to different states of charge obtained by calculating the charging curves of the formation stage collected by embodiment 1 and comparative example 1, wherein the right figure in FIG8 is a partial enlarged view of the left figure. Combined with FIG8, it can be seen that when charged to about 70% SOC, a significant voltage difference begins to appear between embodiment 1 and comparative example 1, and the voltage difference peak between the two is located at about 98% SOC. From the change in the voltage difference between the two, it can be explained to a certain extent that, during the charging process, sodium ions begin to deposit preferentially before potassium ions, and a metal component with mobility (such as sodium-potassium alloy) is formed later and is located on the surface of the negative electrode sheet. Further, relative to directly using aluminum foil as the negative electrode sheet, forming an interface modification layer including a conductive carbon material on the surface of the aluminum foil is beneficial to further improve the cycle life of the battery.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery, wherein: include: An electrolyte and a negative electrode plate, wherein the electrolyte includes sodium ions, M ions and an ether solvent, the volume proportion of the ether solvent in the electrolyte is ≥50%, M is a metal element and includes one or more of potassium, lead, and mercury; when the battery is fully charged, the negative electrode plate includes a fluid metal component, and the metal component includes sodium and M elements.

2. The battery according to claim 1, wherein In the electrolyte, based on the total molar number of the sodium ions and the M ions, the molar proportion of the M ions is ≤50%.

3. The battery according to claim 1 or 2, wherein In the electrolyte, based on the total molar number of the sodium ions and the M ions, the molar proportion of the M ions is ≤20%.

4. The battery according to any one of claims 1 to 3, wherein In the electrolyte, the total molar concentration of sodium ions and M ions is 0.6 mol / L to 2.5 mol / L.

5. The battery according to any one of claims 1 to 4, wherein The volume proportion of the ether solvent in the electrolyte is ≥80%.

6. The battery according to any one of claims 1 to 5, wherein The ether solvent includes halogen-substituted and / or unsubstituted ether solvents.

7. The battery according to claim 6, wherein The unsubstituted ether solvent includes one or more of dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, pentaethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, pentaethylene glycol diethyl ether, diethylene glycol dibutyl ether, tetrahydrofuran, and dioxolane; and / or, The halogen-substituted ether solvent includes one or more of methyl nonafluoro-n-butyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, and octafluoropentyl-tetrafluoroethyl ether.

8. The battery according to any one of claims 1 to 7, wherein The negative electrode plate includes a metal foil.

9. The battery according to claim 8, wherein The metal foil comprises a substrate and a surface modification layer provided on at least one side of the substrate.

10. The battery according to claim 9, wherein The surface modification layer includes a conductive agent.

11. The battery according to claim 9 or 10, wherein The surface modification layer includes a conductive carbon material and a binder, and the binder accounts for 10 wt% to 95 wt% of the surface modification layer.

12. The battery according to claim 11, wherein The binder includes one or more of styrene-butadiene copolymer, acrylate-styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-styrene copolymer, acrylic rubber, butyl rubber, styrene-butadiene rubber, fluororubber, polyethylene, polypropylene, EPDM rubber, EPDM rubber, polyethylene oxide, polyepichlorohydrin, polyvinyl pyrrolidone, polyphosphazene, polyacrylonitrile, polystyrene, polyvinyl pyridine, chlorosulfonated polyethylene, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, hydroxypropyl methylcellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinylidene fluoride, vinylidene fluoride hexafluoropropylene copolymer, polytetrafluoroethylene, polyacrylic acid, polyimide, polyamideimide, polyimide-polyamideimide copolymer, sodium carboxymethyl cellulose, sodium alginate, and / or derivatives of the one or more thereof.

13. The battery according to claim 11 or 12, wherein The binder includes hydroxyl groups and / or carboxyl groups.

14. The battery according to any one of claims 11 to 13, wherein The binder includes one or more of sodium carboxymethyl cellulose, sodium alginate and polyacrylic acid.

15. An electrical device, wherein: include: The battery according to any one of claims 1 to 14.

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