Electrochemical device and electronic device including the same

Abstract

The application provides an electrochemical device and an electronic device comprising the same, the electrochemical device comprising: a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and an electrolyte, wherein the negative electrode comprises a negative electrode current collector and a negative electrode active material layer arranged on the surface of the negative electrode current collector, and the negative electrode active material layer comprises a negative electrode binder having a structural formula I. In the technical scheme of the application, the negative electrode binder has the structural formula I, so that it has a large number of lithium ion exchange sites to improve the ionic conductivity thereof, so as to be capable of improving the fast charging performance and the discharging performance of the electrochemical device in a low-temperature environment.

Description

Technical Field

[0001] This application relates to the field of electrochemical device technology, specifically to an electrochemical device and an electronic device including the electrochemical device. Background Technology

[0002] Electrochemical devices, such as rechargeable batteries, have been widely used in consumer electronics, electric vehicles, aerospace, and other fields due to their advantages such as high energy density, long cycle life, and environmental friendliness. Fast charging performance, as a core indicator of electrochemical device performance, plays a crucial role, especially in consumer electronics, in terms of user experience and widespread adoption.

[0003] For the electrode of an electrochemical device, it typically includes a current collector and an active material layer disposed on the surface of the current collector. The active material layer may contain active material, conductive agent, binder and other components. The binder plays a role in bonding the active material with the current collector, between active materials, and between active material and conductive agent, so as to enhance the electronic contact between the active material and the conductive agent and between the active material and the current collector, and better stabilize the structure of the electrode.

[0004] However, existing binders have poor affinity with the electrolyte in electrochemical devices, which hinders the conduction of lithium ions in the binder during charging and discharging, resulting in increased interfacial impedance of the electrodes. This leads to a decrease in the fast-charging performance of the electrochemical device, especially at low temperatures, where the fast-charging performance of the electrochemical device decreases more significantly, and its discharge performance also decreases severely at low temperatures. Summary of the Invention

[0005] This application provides an electrochemical device and an electronic device including the electrochemical device, which has excellent fast charging and discharging performance in low-temperature environments.

[0006] In a first aspect, this application provides an electrochemical device, the electrochemical device comprising:

[0007] positive electrode;

[0008] The negative electrode includes a negative electrode current collector and a negative electrode active material layer disposed on the surface of the negative electrode current collector, wherein the negative electrode active material layer contains a negative electrode binder having structural formula I:

[0009] A diaphragm is disposed between the positive electrode and the negative electrode;

[0010] Electrolyte;

[0011]

[0012] In structural formula I, m is an integer between 1 and 10000, n is an integer between 1 and 10000, R1 is selected from C1 to C8 alkyl groups, and R2 is selected from C1 to C8 alkyl groups. 15 Alkyl groups.

[0013] In the technical solution of this application, the negative electrode binder has a structural formula I, which gives it a large number of lithium ion exchange sites to improve its ionic conductivity, thereby improving the fast charging performance and discharge performance of the electrochemical device in low temperature environment.

[0014] In some embodiments of this application, the mass percentage of the negative electrode binder is 0.5% to 5.0% based on the total mass of the negative electrode active material layer.

[0015] In some embodiments of this application, the lithium mass percentage in the negative electrode binder is 0.5% to 5% based on the total mass of the negative electrode active material layer.

[0016] In some embodiments of this application, the ionic conductivity of the negative electrode binder is from 0.06 mS / cm to 1.0 mS / cm.

[0017] In some embodiments of this application, the negative electrode binder comprises the following raw materials: aromatic ethylene monomers, olefinic unsaturated carboxylic acid monomers, olefinic unsaturated carboxylic acid ester monomers, and monomers having lithium sulfonate groups.

[0018] In some embodiments of this application, the weight percentage of the monomer having lithium sulfonate groups is 0.5% to 15% based on the total weight of the negative electrode binder.

[0019] In some embodiments of this application, the aromatic vinyl monomer is selected from at least one of styrene, α-methylstyrene, or divinylbenzene;

[0020] The olefinic unsaturated carboxylic acid monomer is selected from at least one of acrylic acid or methacrylic acid;

[0021] The olefinic unsaturated carboxylic acid ester monomer is selected from at least one of methyl acrylate, ethyl acrylate, butyl acrylate, isopropyl acrylate, n-butyl acrylate, hexyl acrylate, heptyl acrylate, isooctyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, or isooctyl methacrylate.

[0022] The monomer having a lithium sulfonate group is selected from at least one of lithium 2-acrylamido-2-methylpropanesulfonate, lithium p-styrenesulfonate, lithium trifluoromethylsulfonate, or lithium dodecyl sulfonate.

[0023] In some embodiments of this application, the raw materials for preparing the negative electrode binder further include crosslinking monomers, wherein the crosslinking monomers are selected from at least one of the following: tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, dipropylene glycol dimethacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, N-hydroxymethylacrylamide, itaconic acid monobutyl ester, divinylbenzene, butadiene, isoprene, dicyclopentadiene, divinylnaphthalene, N,N-methylenebisacrylamide, divinyl phthalate, pentaerythritol diallyl ether, pentaerythritol triallyl ether, pentaerythritol tetraallyl ether, trimethylolpropane diallyl ether, trimethylolpropane triallyl, or polyethyleneimine.

[0024] In some embodiments of this application, the ionic resistance of the negative electrode is 15 mΩ to 25 mΩ.

[0025] Secondly, this application also provides an electronic device, which includes the electrochemical device described in any of the above embodiments.

[0026] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0027] This application can be better understood from the following description of specific embodiments in conjunction with the accompanying drawings, wherein other features, objects and advantages of this application will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, in which the same or similar reference numerals denote the same or similar features.

[0028] Figure 1 Infrared spectra of negative electrode binders prepared according to some embodiments of this application are shown;

[0029] Figure 2 The surface state diagrams of the lithium-ion batteries prepared in Example 1 and Comparative Example 1 are shown when discharged at 1.0C@0℃ and 1.2C@0℃. Detailed Implementation

[0030] The features and exemplary embodiments of various aspects of this application will now be described in detail. Numerous specific details are disclosed in the following detailed description to provide a comprehensive understanding of this application. However, it will be apparent to those skilled in the art that this application can be implemented without some of these specific details. The following description of embodiments is merely intended to provide a better understanding of this application by illustrating examples. This application is by no means limited to any specific configurations and algorithms presented below, but covers any modifications, substitutions, and improvements to elements, components, and algorithms without departing from the spirit of this application. Well-known structures and techniques are not shown in the accompanying drawings and the following description in order to avoid unnecessary obfuscation of this application.

[0031] This application provides an electrochemical device, including a positive electrode, a negative electrode, a membrane disposed between the positive and negative electrodes, and an electrolyte. The negative electrode includes a negative electrode current collector and a negative electrode active material layer disposed on the surface of the negative electrode current collector. The negative electrode active material layer contains a negative electrode binder having structural formula I.

[0032]

[0033] In structural formula I, m is an integer between 1 and 10000, n is an integer between 1 and 10000, R1 is selected from C1 to C8 alkyl groups, and R2 is selected from C1 to C8 alkyl groups. 15 Alkyl groups.

[0034] In the technical solution of this application, the negative electrode binder has a structural formula I, which gives it a large number of lithium ion exchange sites to improve its ionic conductivity, thereby improving the fast charging performance and discharge performance of the electrochemical device in low temperature environment.

[0035] In some embodiments of this application, the mass percentage of the negative electrode binder is 0.5% to 5.0% based on the total mass of the negative electrode active material layer. A mass percentage of negative electrode binder within this range can reduce the ionic resistance of the negative electrode, which is beneficial for improving the fast-charging and discharging performance of the electrochemical device in low-temperature environments.

[0036] For example, the mass percentage of the negative electrode binder may be, but is not limited to, 0.50%, 0.60%, 0.70%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, 1.05%, 1.1%, 1.15%, 1.2%, 1.25%, 1.3%, 1.35%, 1.4%, 1.45%, 1.5%, 1.55%, 1.6%, 1.65%, 1.7%, 1.75%, 1.8%, 1.85%, 1.9%, 1.95%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, or 5.0%.

[0037] In some embodiments of this application, the lithium mass percentage in the negative electrode binder is 0.5% to 5% based on the total mass of the negative electrode active material layer. A lithium mass percentage in the negative electrode binder within this range allows the negative electrode to have a large number of lithium-ion exchange sites to improve its ionic conductivity, thereby enhancing the fast-charging and discharging performance of the electrochemical device in low-temperature environments.

[0038] For example, the mass percentage of lithium in the negative electrode binder may, but is not limited to, 0.50%, 0.55%, 0.60%, 0.65%, 0.70%, 0.75%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, 1.05%, 1.1%, 1.15%, 1.2%, 1.25%, 1.3%, 1.35%, or 1. 4%, 1.45%, 1.5%, 1.55%, 1.6%, 1.65%, 1.7%, 1.75%, 1.8%, 1.85%, 1.9%, 1.95%, 2.0%, 2.05%, 2.1%, 2.15%, 2.2%, 2.25%, 2.3%, 2.35%, 2.4%, 2.45%, 2.5%, 2.55%, 2.6 %, 2.65%, 2.7%, 2.75%, 2.8%, 2.85%, 2.9%, 2.95%, 3.0%, 3.05%, 3.1%, 3.15%, 3.2%, 3.25%, 3.3%, 3.35%, 3.4%, 3.45%, 3.5%, 3.55%, 3.6%, 3.65%, 3.7%, 3.75%, 3.8% 3.85%, 3.9%, 3.95%, 4.0%, 4.05%, 4.1%, 4.15%, 4.2%, 4.25%, 4.3%, 4.35%, 4.4%, 4.45%, 4.5%, 4.55%, 4.6%, 4.65%, 4.7%, 4.75%, 4.8%, 4.85%, 4.9%, 4.95%, 5.0%.

[0039] In some embodiments of this application, the ionic conductivity of the binder is 0.06 mS / cm to 1.0 mS / cm. The ionic conductivity of the binder within this range promotes lithium-ion conduction, thereby improving the fast-charging and discharging performance of the electrochemical device at low temperatures.

[0040] For example, the ionic conductivity of the adhesive may be, but is not limited to, 0.060 mS / cm, 0.061 mS / cm, 0.062 mS / cm, 0.063 mS / cm, 0.064 mS / cm, 0.065 mS / cm, 0.066 mS / cm, 0.067 mS / cm, 0.068 mS / cm, 0.069 mS / cm, 0.070 mS / cm, 0.071 mS / cm, 0.072 mS / cm, 0.073 mS / cm, 0.074 mS / cm, 0.075 mS / cm, 0.076 mS / cm, 0.077 mS / cm, 0.078 mS / cm, 0.079 mS / cm, 0.080 mS / cm, etc. cm, 0.081mS / cm, 0.082mS / cm, 0.083mS / cm, 0.084mS / cm, 0.085mS / cm, 0.086mS / cm, 0.087mS / cm, 0.088mS / cm, 0.089mS / cm, 0.090mS / cm, 0.091mS / cm, 0 .092mS / cm, 0.093mS / cm, 0.094mS / cm, 0.095mS / cm, 0.096mS / cm, 0.097mS / cm, 0.098mS / cm, 0.099mS / cm, 0.10mS / cm, 0.20mS / cm, 0.50mS / cm, 1.0mS / cm.

[0041] In some embodiments of this application, the negative electrode binder having structural formula I comprises the following raw material components by weight percentage:

[0042] Aromatic ethylene monomers, 40% to 90%;

[0043] Alkene unsaturated carboxylic acid monomers, 1% to 10%;

[0044] Alkene unsaturated carboxylic acid ester monomers, 40% to 90%;

[0045] Monomers having lithium sulfonate groups, 0.5% to 15%;

[0046] Initiator, 0.04% to 1.5%;

[0047] Emulsifier, 0.05% to 1.5%;

[0048] Crosslinking monomer, 0.5% to 2%;

[0049] The sum of the weight percentages of each raw material component is 100%.

[0050] In the embodiments of this application, aromatic ethylene monomers, as the first hard monomers, can impart cohesive force to the binder. This cohesive force enables the electrode to maintain its original structure at low temperatures, i.e., resist deformation under external forces. Furthermore, the weight percentage of the aromatic ethylene monomers is controlled within the range of 40% to 90%, which is beneficial for improving the fast charging and discharging performance of the electrochemical device at low temperatures.

[0051] For example, the weight percentage of aromatic ethylene monomers may be, but is not limited to, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%.

[0052] For example, the aromatic vinyl monomers described above may be selected from at least one of styrene, α-methylstyrene, and divinylbenzene. It is understood that the aromatic vinyl monomers are any one or more mixtures of styrene, α-methylstyrene, and divinylbenzene, and the sum of the weight percentages of the monomers in the mixture may be arbitrarily combined in the range of 40% to 90%.

[0053] In the embodiments of this application, the olefinic unsaturated carboxylic acid monomer is used as a second hard monomer to work synergistically with the aromatic ethylene monomer to improve the cohesive force of the binder. Moreover, the weight percentage of the olefinic unsaturated carboxylic acid monomer is controlled within the range of 1% to 10%, which is beneficial to improving the fast charging performance and discharge performance of the electrochemical device in low temperature environment.

[0054] For example, the weight percentage of the olefinic unsaturated carboxylic acid monomer may be, but is not limited to, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%.

[0055] In some embodiments of this application, the olefinic unsaturated carboxylic acid monomer is selected from at least one of acrylic acid and methacrylic acid.

[0056] In the embodiments provided in this application, the olefinic unsaturated carboxylic acid ester monomer, as a soft monomer, can impart adhesive properties to the binder, enabling the binder to bond the active material to the current collector, between active materials, and between the active material and the conductive agent, thereby enhancing the electronic contact between the active material and the conductive agent, and between the active material and the current collector, and better stabilizing the structure of the electrode. Furthermore, the weight percentage of the olefinic unsaturated carboxylic acid ester monomer is controlled within the range of 40% to 90%.

[0057] For example, the weight percentage of the olefinic unsaturated carboxylic acid ester monomer may be, but is not limited to, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%.

[0058] In some embodiments of this application, olefinic unsaturated carboxylic acid ester monomers can crosslink with aromatic ethylene monomers and olefinic unsaturated carboxylic acid monomers to form emulsions. Since olefinic unsaturated carboxylic acid ester monomers have ester functional groups, this can increase the affinity between the binder and the electrolyte, which is beneficial to improving the ionic conductivity of the binder. Moreover, the molecular chain of the emulsion has a large number of electronegative elements, i.e., lone pairs of electrons, which will continuously undergo complexation / de-complexation reactions with lithium ions under the action of an electric field, which is beneficial to the diffusion of lithium ions. This is conducive to improving the fast charging performance and discharge performance of the electrochemical device in low-temperature environments.

[0059] For example, the olefinic unsaturated carboxylic acid ester monomer is selected from at least one of methyl acrylate, ethyl acrylate, butyl acrylate, isopropyl acrylate, n-butyl acrylate, hexyl acrylate, heptyl acrylate, isooctyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, and isooctyl methacrylate. It is understood that the olefinic unsaturated carboxylic acid ester monomer can be any one or a mixture of two or more of methyl acrylate, ethyl acrylate, butyl acrylate, isopropyl acrylate, n-butyl acrylate, hexyl acrylate, heptyl acrylate, isooctyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, and isooctyl methacrylate, and the sum of the weight percentages of the monomers in the mixture can be arbitrarily combined within the range of 40% to 90%.

[0060] In the embodiments of this application, the monomer with lithium sulfonate group is used as a functional monomer to modify the emulsion formed by hard monomer and soft monomer, so that it has a large number of lithium ion exchange sites to improve its ionic conductivity. Moreover, the weight percentage of the monomer with lithium sulfonate group is controlled within the range of 0.5% to 15.0%, thereby improving the fast charging performance and discharge performance of the electrochemical device in low temperature environment.

[0061] For example, the weight percentage of monomers having lithium sulfonate groups may, but is not limited to, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0%, 8.5%, 9.0%, 9.5%, 10.0%, 10.5%, 11.0%, 11.5%, 12.0%, 12.5%, 13.0%, 13.5%, 14.0%, 14.5%, and 15.0%.

[0062] In some embodiments of this application, the monomer having a lithium sulfonate group is selected from at least one of lithium 2-acrylamido-2-methylpropanesulfonate, lithium p-styrenesulfonate, lithium trifluoromethanesulfonate, and lithium dodecyl sulfonate. It is understood that the monomer having a lithium sulfonate group can be any one or a mixture of two or more of lithium 2-acrylamido-2-methylpropanesulfonate, lithium p-styrenesulfonate, lithium trifluoromethanesulfonate, and lithium dodecyl sulfonate, and the sum of the weight percentages of each monomer in the mixture can be arbitrarily combined within the range of 0.5% to 15.0%.

[0063] In the embodiments of this application, the initiator is capable of initiating the polymerization reaction of aromatic ethylene monomers, olefinic unsaturated carboxylic acid monomers, olefinic unsaturated carboxylic acid ester monomers and monomers having lithium sulfonate groups to form an emulsion, and its weight percentage content is controlled within the range of 0.04% to 1.5%.

[0064] For example, the weight percentage of the initiator may be, but is not limited to, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, 0.40%, 0.45%, 0.50%, 0.55%, 0.60%, 0.65%, 0.70%, 0.75%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, 1.05%, 1.1%, 1.15%, 1.2%, 1.25%, 1.3%, 1.35%, 1.4%, 1.45%, or 1.5%.

[0065] In some embodiments of this application, the initiator is selected from peroxides and / or azo compounds.

[0066] For example, the peroxide is selected from at least one of benzoyl peroxide, tert-butyl hydroperoxide, ammonium persulfate, and potassium persulfate. It is understood that the peroxide can be any mixture of benzoyl peroxide, tert-butyl hydroperoxide, ammonium persulfate, and potassium persulfate, or a mixture of two or more of them, and the sum of the weight percentages of each peroxide in the mixture can be arbitrarily combined in the range of 0.04% to 1.5%.

[0067] For example, the azo compound is selected from at least one of azobisisobutyronitrile, azobisisoheptanenitrile, azobiscyclohexylformitrile, azobisisobutyramidine hydrochloride, and azobisisobutyramidine hydrochloride. It is understood that the azo compound can be any one or a mixture of two or more of azobisisobutyronitrile, azobisisoheptanenitrile, azobiscyclohexylformitrile, azobisisobutyramidine hydrochloride, and azobisisobutyramidine hydrochloride, and the sum of the weight percentages of each azo compound in the mixture can be arbitrarily combined within the range of 0.04% to 1.5%.

[0068] In some specific embodiments of this application, the initiator may be selected from V-50 initiator, VA-044 initiator, or VA061 initiator.

[0069] In some embodiments of this application, the initiators include peroxides and azo compounds, the specific types of which are as described above, and the total weight percentage of these initiators can be arbitrarily combined in the range of 0.04% to 1.5%.

[0070] In the embodiments of this application, the emulsifier acts as an emulsifier, facilitating the formation of stable emulsions from aromatic ethylene monomers, olefinically unsaturated carboxylic acid monomers, olefinically unsaturated carboxylic acid ester monomers, and monomers with lithium sulfonate groups. In the embodiments of this application, the weight percentage of the emulsifier is controlled within the range of 0.05% to 1.5%.

[0071] For example, the weight percentage of the emulsifier may be, but is not limited to, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, 0.40%, 0.45%, 0.50%, 0.55%, 0.60%, 0.65%, 0.70%, 0.75%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, 1.05%, 1.1%, 1.15%, 1.2%, 1.25%, 1.3%, 1.35%, 1.4%, 1.45%, or 1.5%.

[0072] In some embodiments of this application, the emulsifier is selected from at least one of anionic emulsifiers and nonionic emulsifiers. These emulsifiers help to improve the affinity between the binder and the electrolyte, thereby facilitating the conduction of lithium ions in the binder and reducing the interfacial impedance of the electrode, thus improving the fast charging and discharging performance of the electrochemical device in low-temperature environments.

[0073] In some embodiments of this application, the anionic emulsifier may be selected from at least one of carboxylates, sulfates, and sulfonates. Exemplary examples include potassium laurate, sodium dodecyl sulfate (C12H25OSO3Na), and sodium dioctyl succinate sulfonate.

[0074] In some embodiments of this application, the nonionic emulsifier is selected from fatty alcohol polyoxyethylene ether and / or alkylphenol polyoxyethylene ether.

[0075] In the embodiments of this application, the crosslinking monomer enables the monomer to undergo covalent crosslinking. In the embodiments of this application, the weight percentage of the crosslinking monomer is controlled within the range of 0.5% to 2%.

[0076] For example, the weight percentage of crosslinking monomers may be, but is not limited to, 0.50%, 0.55%, 0.60%, 0.65%, 0.70%, 0.75%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, 1.05%, 1.1%, 1.15%, 1.2%, 1.25%, 1.3%, 1.35%, 1.4%, 1.45%, 1.5%, 1.55%, 1.6%, 1.65%, 1.7%, 1.75%, 1.8%, 1.85%, 1.9%, 1.95%, or 2.0%.

[0077] In some embodiments of this application, the crosslinking monomer is selected from acrylic crosslinking monomers and / or olefin crosslinking monomers.

[0078] For example, the acrylic crosslinking monomer is selected from at least one of tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, dipropylene glycol dimethacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, and N-hydroxymethylacrylamide. It is understood that the acrylic crosslinking monomer can be any one or a mixture of two or more of tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, dipropylene glycol dimethacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, and N-hydroxymethylacrylamide, and the sum of the weight percentages of each crosslinking monomer in the mixture can be arbitrarily combined within the range of 0.5% to 2.0%.

[0079] For example, the olefin crosslinking monomer is selected from at least one of itaconic acid monobutyl ester, divinylbenzene, butadiene, isoprene, dicyclopentadiene, divinylnaphthalene, N,N-methylenebisacrylamide, divinyl phthalate, pentaerythritol diallyl ether, pentaerythritol triallyl ether, pentaerythritol tetraallyl ether, trimethylolpropane diallyl ether, trimethylolpropane triallyl, and polyethyleneimine. It is understood that the olefin crosslinking monomer can be any one or a mixture of two or more of the above, and the sum of the weight percentages of the various crosslinking monomers in the mixture can be arbitrarily combined within the range of 0.5% to 2.0%.

[0080] In some embodiments of this application, the crosslinking monomers may include acrylic crosslinking monomers and olefin crosslinking monomers. The specific types of acrylic crosslinking monomers and olefin crosslinking monomers are as described above. The sum of the weight percentages of these crosslinking monomers can be arbitrarily combined in the range of 0.5% to 2.0%.

[0081] This application also provides a method for manufacturing a negative electrode binder, the method comprising the following steps:

[0082] S10: Mix aromatic ethylene monomers, olefinic unsaturated carboxylic acid monomers, olefinic unsaturated carboxylic acid ester monomers, monomers with lithium sulfonate groups and a portion of emulsifiers, then add them to a portion of water for emulsification to obtain a pre-emulsion.

[0083] S20: Mix part of the initiator with the remaining emulsifier and water, then mix with part of the pre-emulsion and heat to about 80°C. Then slowly add the remaining initiator and crosslinking monomer, and control the temperature of the reaction solution to about 80°C.

[0084] S30: Slowly add the remaining pre-emulsion to the reaction carried out in step S20 and keep warm for about 4 hours;

[0085] S40: After the reaction is complete, cool to room temperature and adjust the pH of the product to obtain the negative electrode binder.

[0086] In some embodiments of this application, the negative electrode current collector can be made of materials such as metal foil or porous metal plate. For example, the material of the negative electrode current collector can be, but is not limited to, foil or porous plate of metals such as copper, nickel, titanium, or iron, or their alloys. Further, in some specific embodiments of this application, the negative electrode current collector is made of copper foil.

[0087] The negative electrode active material in the negative electrode active material layer may be, but is not limited to, one or more of the following: natural graphite, artificial graphite, soft carbon, hard carbon, mesophase carbon microspheres, nano-carbon, carbon fiber, elemental silicon, silicon oxide, silicon-carbon composite, silicon alloy, elemental tin, tin oxide, tin-carbon composite, tin alloy, and lithium titanate.

[0088] In addition to the negative electrode active material, the negative electrode active material layer also includes a conductive agent and a binder. This application does not impose specific limitations on the type of conductive agent in the negative electrode active material layer; it can be selected according to actual needs. The binder is the negative electrode binder described in the above embodiments. The specific components of this negative electrode binder are described above and will not be repeated here.

[0089] For example, the conductive agent may be, but is not limited to, one or more of graphite, superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0090] In some embodiments of this application, the negative electrode active material layer may also include a thickener, such as carboxymethyl cellulose (CMC).

[0091] The aforementioned negative electrode can be prepared according to conventional methods in the art. As an example, a negative electrode active material (e.g., graphite), a conductive agent (e.g., carbon black), a negative electrode binder, and a solvent are mixed in the above proportions to obtain a negative electrode slurry; the negative electrode slurry is coated onto the surface of a copper foil, and after drying and other processes, a negative electrode is obtained.

[0092] In the embodiments of this application, the positive electrode includes a positive current collector and a positive active material layer disposed on the surface of the positive current collector. There are no specific limitations on the positive current collector and the positive active material layer, and they can be selected according to actual needs.

[0093] In some embodiments of this application, the positive current collector may be, but is not limited to, a metal foil or a porous metal foil. For example, the positive current collector may be one or more of aluminum, aluminum alloys, copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys.

[0094] In some embodiments of this application, the positive electrode active material layer includes a positive electrode active material, a conductive agent, a binder, and a solvent, and the positive electrode active material layer is capable of reversible lithium ion insertion / extraction.

[0095] For example, the positive electrode active material may be a lithium transition metal complex, wherein the transition metal may be one or more of Mn, Fe, Ni, Co, Cr, Ti, Zn, V, Al, Zr, Ce and Mg.

[0096] As an example, a lithium transition metal complex could be lithium cobalt oxide.

[0097] For example, the adhesive may be one or more of styrene-butadiene rubber (SBR), carboxymethyl cellulose (CMC), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), ethylene-vinyl acetate copolymer (EVA), polyvinyl alcohol (PVA), and polyvinyl butyral (PVB).

[0098] For example, the conductive agent is one or more of graphite, superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0099] The aforementioned positive electrode can be prepared according to conventional methods in the art. As an example, a positive electrode active material (e.g., lithium cobalt oxide), a conductive agent (e.g., carbon black), and a binder (e.g., polyvinylidene ethylene) are dispersed in a solvent (e.g., N-methylpyrrolidone, abbreviated as NMP) to form a uniform positive electrode slurry. The positive electrode slurry is then coated onto a positive electrode current collector, and after drying and other processes, the positive electrode is obtained.

[0100] In the embodiments of this application, the diaphragm is not specifically limited and can be any diaphragm known in the art. For example, the diaphragm may be a single-layer or multi-layer film made of one or more of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0101] In the embodiments of this application, no specific limitations are placed on the electrolyte, and it can be any electrolyte known in the art. Exemplarily, the electrolyte includes an organic solvent and an electrolyte salt, wherein the organic solvent may be 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), butenyl 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), or 1,4-butyrolactone (GBL). One or more of sulfolane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS), and diethyl sulfone (ESE); the electrolyte salt may be one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluorooxalate borate (LiDFOB), lithium dioxalate borate (LiBOB), lithium difluorophosphate (LiPO2F2), lithium difluorodioxalate phosphate (LiDFOP), and lithium tetrafluorooxalate phosphate (LiTFOP).

[0102] The electrochemical device described in this application is not particularly limited and may include any device in which an electrochemical reaction occurs. In some embodiments, the electrochemical device may include, but is not limited to, a lithium-ion battery.

[0103] The preparation process of electrochemical devices is well known to those skilled in the art, and this application does not impose any particular limitations. For example, it may include, but is not limited to, the following steps: stacking the positive electrode, separator, and negative electrode in sequence, and performing operations such as winding and folding as needed to obtain a wound electrode assembly; placing the electrode assembly in a packaging bag; injecting electrolyte into the packaging bag and sealing it to obtain the electrochemical device; or stacking the positive electrode, separator, and negative electrode in sequence, and then fixing the four corners of the entire stacked structure with tape to obtain a stacked electrode assembly; placing the electrode assembly in a packaging bag; injecting electrolyte into the packaging bag and sealing it to obtain the electrochemical device. In addition, overcurrent protection elements, conductive plates, etc., may be placed in the packaging bag as needed to prevent pressure rise and overcharging / discharging inside the electrochemical device.

[0104] In some embodiments of this application, the discharge rate of the above-described electrode assembly is 40% to 48% under conditions of -20°C, 3.4V, and 0.2C.

[0105] This application also provides an electronic device comprising the electrochemical device in any of the foregoing embodiments of this application. The electrochemical device provided by this application has good cycle performance and safety performance, thereby providing the electronic device with a long service life and good performance.

[0106] The electronic device described in this application is not particularly limited and can be any electronic device known in the prior art. For example, electronic devices include, but are not limited to, laptops, pen-based computers, mobile computers, e-book players, portable telephones, portable fax machines, portable copiers, portable printers, stereo headphones, video recorders, LCD TVs, portable cleaners, portable CD players, mini CDs, transceivers, electronic notebooks, calculators, memory cards, portable recorders, radios, backup power supplies, motors, automobiles, motorcycles, electric bicycles, bicycles, lighting fixtures, toys, game consoles, clocks, power tools, flashlights, cameras, large household batteries, and lithium-ion capacitors, etc.

[0107] The following specific embodiments use lithium-ion batteries as examples of electrochemical devices to explain this application in detail; however, the electrochemical devices of this application are not limited to lithium-ion batteries. Those skilled in the art should understand that the following descriptions are merely illustrative and do not limit the scope of protection of this application. In the following embodiments, all raw material components are expressed in parts by weight.

[0108] Example 1

[0109] This embodiment provides a method for preparing a negative electrode binder, as detailed below:

[0110] S10: Mix 1 part fatty alcohol polyoxyethylene ether, 25 parts styrene, 24 parts butyl acrylate, 1.5 parts acrylic acid and 5 parts lithium 2-acrylamide-2-methylpropanesulfonate, and emulsify in 39.95 parts water to obtain a pre-emulsion.

[0111] S20: Mix 0.05 parts azobisisobutyronitrile, 0.5 parts fatty alcohol polyoxyethylene ether and 6 parts water evenly, then pour 1 / 3 of the pre-emulsion into the reaction vessel and heat and stir. When the temperature reaches about 80°C, slowly add 0.05 parts azobisisobutyronitrile and 1 part tripropylene glycol diacrylate, and control the temperature at about 80°C.

[0112] S30: Slowly add the remaining 2 / 3 of the emulsion, keeping the emulsion in a bluish-green state, and incubate for about 4 hours;

[0113] S40: After the reaction is complete, cool to room temperature and adjust the pH value to between 7 and 8 to obtain the negative electrode binder.

[0114] Preparation of the negative electrode: Artificial graphite, carbon black, sodium carboxymethyl cellulose, and negative electrode binder were added to water in a weight ratio of 97.3:0.5:1.2:1.0 and stirred to obtain a negative electrode slurry. The negative electrode slurry was coated onto a 6 μm thick copper foil using an extrusion coating machine at a coating speed of 18 m / min. The foil was then baked in an oven until the electrode was dry to obtain the negative electrode.

[0115] Preparation of the positive electrode: Lithium cobalt oxide, carbon black, polyvinylidene fluoride and NMP solvent are stirred to form a positive electrode slurry. The positive electrode slurry is then coated on the surface of a 6µm thick aluminum foil and dried to obtain the positive electrode.

[0116] The diaphragm is made of ceramic coating on one side and water-based vinylidene fluoride-hexafluoropropylene copolymer coating on both sides.

[0117] Electrolyte: 1 mol / L lithium hexafluorophosphate + (ethylene carbonate + propylene carbonate + diethyl carbonate + ethyl propionate + fluoroethylene carbonate + 1,3-propanesulfonyl lactone) solvent.

[0118] The positive and negative electrodes are welded with tabs, then wound with a separator to form a cell. The cells are then packaged with an aluminum-plastic film, baked in a vacuum for 24 hours to remove moisture, injected with electrolyte, and left to stand at high temperature. The cells are then formed and sorted to obtain square soft-pack lithium-ion batteries with a thickness / width / height of 3.8 mm, 64 mm, and 82 mm, respectively.

[0119] Example 2

[0120] The difference between this embodiment and Embodiment 1 is that 0.5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0121] Example 3

[0122] The difference between this embodiment and Embodiment 1 is that 3 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0123] Example 4

[0124] The difference between this embodiment and Embodiment 1 is that 10 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0125] Example 5

[0126] The difference between this embodiment and Embodiment 1 is that 15 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0127] Example 6

[0128] The difference between this embodiment and Embodiment 1 is that 5 parts of lithium p-styrene sulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0129] Example 7

[0130] The difference between this embodiment and Embodiment 1 is that 5 parts of lithium p-trifluoromethanesulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0131] Example 8

[0132] The difference between this embodiment and Example 1 is that 5 parts of lithium dodecyl sulfonate monomer are used instead of 5 parts of lithium 2-acrylamide-2-methylpropanesulfonate monomer.

[0133] Example 9:

[0134] The difference between this embodiment and Embodiment 1 is that: artificial graphite, carbon black, sodium carboxymethyl cellulose, and negative electrode binder are added to water in a weight ratio of 97.5:0.5:1.2:0.8 and stirred to obtain a negative electrode slurry; the above negative electrode slurry is coated on the surface of a 6µm thick copper foil to obtain a negative electrode.

[0135] Example 10

[0136] The difference between this embodiment and Embodiment 1 is that: artificial graphite, carbon black, sodium carboxymethyl cellulose, and negative electrode binder are added to water in a weight ratio of 97.1:0.5:1.2:1.2 and stirred to obtain a negative electrode slurry; the above negative electrode slurry is coated on the surface of a 6µm thick copper foil to obtain a negative electrode.

[0137] Comparative Example 1

[0138] The difference between this comparative example and Example 1 is that lithium 2-acrylamide-2-methylpropanesulfonate was not added.

[0139] Test case

[0140] The lithium-ion batteries prepared in Examples 1 to 10 and Comparative Example 1 were subjected to performance testing. The testing process is as follows:

[0141] (1) Stability of negative electrode slurry

[0142] Take a cup of negative electrode slurry and place it in a room temperature environment. After 48 hours, scrape the slurry with an iron sheet or scraper. Then, hold the iron sheet or scraper vertically and let the slurry flow naturally. If there are clumps of slurry remaining on the iron sheet or scraper and cannot be left normally, the slurry will settle. Otherwise, the slurry will not settle.

[0143] (2) Lithium content

[0144] Take 0.5g of binder film / negative electrode powder (powder scraped off the electrode), digest it with 10ml of nitric acid, and then test it with ICP-OES (PE 7000DV). The spectral lines are compared with those obtained by the standard curve method to determine the lithium content.

[0145] (3) Infrared testing

[0146] Powder was scraped off the negative electrode sheet and dried under an alcohol lamp. The dried powder was then mixed with potassium bromide powder at a ratio of 1:100, pressed into a disc in an infrared die, and then placed in a Nicoletis 10 infrared spectrometer to obtain the infrared spectrum. Figure 1 As shown.

[0147] (4) Ion resistance

[0148] The negative electrode was punched to a size of 23mm*35mm and assembled into a symmetrical battery with the separator and pocket in a glove box. Two drops of electrolyte were added, and the battery was sealed. The symmetrical battery was then placed in a charge-discharge test channel for testing, and the ion resistance Rion was calculated according to Nm=(Rion·A·κ) / d.

[0149] (5) Ionic conductivity

[0150] The negative electrode binder was made into a uniform thickness film, and SS / thin film / SS cells were assembled. The film was sandwiched between two stainless steel sheet electrodes. The electrochemical workstation was used for testing, and the scanning frequency range was 1Hz-105Hz to obtain the EIS curve. The ionic conductivity was calculated according to the formula: σ=d / (Rb×S).

[0151] (6) Discharge rate

[0152] The battery cell was fully charged and placed in a 25°C constant temperature chamber. It was discharged from 0.2C to 3.4V, and the initial capacity was recorded as q1. Then, another fully charged battery cell was placed in a -20°C constant temperature chamber and discharged from 0.2C to 3.4V. The initial capacity was recorded as q2, and the discharge rate was (q1-q2) / q1*100%.

[0153] (7) 1.2C@0℃ discharge test

[0154] Discharge the battery cell, then charge it to full capacity at 1.2C in a 0℃ constant temperature chamber, then discharge it to 3.0V at 0.5C. Repeat the 1.2C charging and 0.5C discharging cycle for a total of 9 cycles, then charge it to full capacity at 1.2C. Disassemble the interface and take photos to observe the lithium plating.

[0155] (8) 1.0C@0℃ discharge test

[0156] Discharge the battery cell, then charge it to full capacity at 1.0C in a 0℃ constant temperature chamber, then discharge it to 3.0V at 0.5C. Repeat the 1.0C charging and 0.5C discharging for a total of 9 cycles, then charge it to full capacity at 1.0C. Disassemble the interface and take photos to observe the lithium plating.

[0157] (9) Cycle retention rate

[0158] The cell is charged and discharged once, and the initial capacity is recorded as q3. It is then charged and discharged for another 500 cycles, and the capacity after 500 cycles is recorded as q4. The capacity retention rate after 500 cycles at 25℃ is (q3-q4) / q3*100%.

[0159] Table 1

[0160] Test case Monomers with lithium sulfonate groups and their content Content of negative electrode binder Stability of negative electrode slurry Example 1 Lithium 2-acrylamide-2-methylpropanesulfonate, 5% 1.0％ No sediment Example 2 Lithium 2-acrylamide-2-methylpropanesulfonate, 0.5% 1.0％ No sediment Example 3 Lithium 2-acrylamide-2-methylpropanesulfonate, 3% 1.0％ No sediment Example 4 Lithium 2-acrylamide-2-methylpropanesulfonate, 10% 1.0％ No sediment Example 5 Lithium 2-acrylamide-2-methylpropanesulfonate, 15% 1.0％ No sediment Example 6 Lithium styrene sulfonate, 5% 1.0％ No sediment Example 7 Lithium trifluoromethanesulfonate, 5% 1.0％ No sediment Example 8 Lithium dodecyl sulfonate, 5% 1.0％ No sediment Example 9 Lithium 2-acrylamide-2-methylpropanesulfonate, 5% 0.8％ No sediment Example 10 Lithium 2-acrylamide-2-methylpropanesulfonate, 5% 1.2％ No sediment Comparative Example 1 none 1.0％ No sediment

[0161] Table 2

[0162]

[0163]

[0164] Table 3

[0165] Test case Discharge rate Discharge at 1.5C@12℃ Discharge at 1.0C@0℃ 25℃ cycling for 500cls capacity retention Example 1 41.50％ Non-lithium plating Non-lithium plating 93.00％ Example 2 40.90％ Slight lithium plating Slight lithium plating 92.80％ Example 3 41.20％ Non-lithium plating Slight lithium plating 93.00％ Example 4 41.80％ Non-lithium plating Non-lithium plating 92.90％ Example 5 41.00％ Slight lithium plating Slight lithium plating 93.00％ Example 6 41.60％ Non-lithium plating Non-lithium plating 93.00％ Example 7 40.90％ Non-lithium plating Slight lithium plating 93.00％ Example 8 40.80％ Non-lithium plating Slight lithium plating 93.00％ Example 9 41.90％ Non-lithium plating Non-lithium plating 92.90％ Example 10 40.50％ Non-lithium plating Non-lithium plating 92.80％ Comparative Example 1 39.2％ Severe lithium plating Severe lithium plating 92.8％

[0166] Figure 1 Infrared spectra of negative electrode binders prepared according to some embodiments of this application are shown. Figure 1 It can be seen from this that at 1160cm -1 and 1050cm -1 There are obvious characteristic peaks of sulfonic acid groups.

[0167] Figure 2The diagram shows surface state diagrams of the lithium-ion batteries prepared in Example 1 and Comparative Example 1 at 1.0C@0℃ and 1.0C@0℃ discharge. Figure 2 As can be seen from the data, the lithium plating in Example 1 during discharge is significantly better than that in Comparative Example 1.

[0168] Furthermore, as shown in Tables 1 to 3, the negative electrode binder with structural formula I can have a large number of lithium-ion exchange sites to improve its ionic conductivity, thereby improving the fast charging and discharging performance of lithium-ion batteries in low-temperature environments.

[0169] Those skilled in the art will understand that the above embodiments are exemplary and not restrictive. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Based on a study of the drawings, specification, and claims, those skilled in the art should be able to understand and implement other variations of the disclosed embodiments. In the claims, the term "comprising" does not exclude other components or steps; "article" without the use of a quantifier is intended to include one or more articles and can be used interchangeably with "one or more articles"; the terms "first" and "second" are used to identify names and not to indicate any particular order. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. An electrochemical device, wherein, The electrochemical device includes: positive electrode; The negative electrode includes a negative electrode current collector and a negative electrode active material layer disposed on the surface of the negative electrode current collector, wherein the negative electrode active material layer contains a negative electrode binder having structural formula I: In structural formula I, m is an integer between 1 and 10000, n is an integer between 1 and 10000, R1 is selected from C1 to C8 alkyl groups, and R2 is selected from C1 to C8 alkyl groups. 15 Alkyl groups; The negative electrode binder comprises the following raw materials: aromatic ethylene monomers, olefinic unsaturated carboxylic acid monomers, olefinic unsaturated carboxylic acid ester monomers, and monomers having lithium sulfonate groups; based on the total weight of the negative electrode binder, the weight percentage of the monomers having lithium sulfonate groups is 0.5% to 15%. A diaphragm is disposed between the positive electrode and the negative electrode; Electrolyte.

2. The electrochemical device according to claim 1, wherein, Based on the total mass of the negative electrode active material layer, the mass percentage of the negative electrode binder is 0.5% to 5.0%.

3. The electrochemical device according to claim 1, wherein, Based on the total mass of the negative electrode active material layer, the lithium mass percentage in the negative electrode binder is 0.5% to 5%.

4. The electrochemical device according to claim 1, wherein, The negative electrode binder has an ionic conductivity of 0.06 mS / cm to 1.0 mS / cm.

5. The electrochemical device according to claim 1, wherein, The aromatic vinyl monomer is selected from at least one of styrene, α-methylstyrene or divinylbenzene; The olefinic unsaturated carboxylic acid monomer is selected from at least one of acrylic acid or methacrylic acid; The olefinic unsaturated carboxylic acid ester monomer is selected from at least one of methyl acrylate, ethyl acrylate, butyl acrylate, isopropyl acrylate, n-butyl acrylate, hexyl acrylate, heptyl acrylate, isooctyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, or isooctyl methacrylate. The monomer having a lithium sulfonate group is selected from at least one of lithium 2-acrylamido-2-methylpropanesulfonate, lithium p-styrenesulfonate, lithium trifluoromethylsulfonate, or lithium dodecyl sulfonate.

6. The electrochemical device according to claim 5, wherein, The raw materials for preparing the negative electrode binder also include crosslinking monomers, which are selected from at least one of the following: tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, dipropylene glycol dimethacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, N-hydroxymethylacrylamide, itaconic acid monobutyl ester, divinylbenzene, butadiene, isoprene, dicyclopentadiene, divinylnaphthalene, N,N-methylenebisacrylamide, divinyl phthalate, pentaerythritol diallyl ether, pentaerythritol triallyl ether, pentaerythritol tetraallyl ether, trimethylolpropane diallyl ether, trimethylolpropane triallyl, or polyethyleneimine.

7. The electrochemical device according to claim 1, wherein, The ionic resistance of the negative electrode is 15mΩ to 25mΩ.

8. An electronic device, wherein, The electronic device includes the electrochemical device as described in any one of claims 1 to 7.

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