Metal-containing electrolyte and method for producing same

Abstract

Some embodiments in the present disclosure provide metal-containing electrolytes and methods of making the same. The metal-containing electrolyte comprises a structure shown in the following formula I, wherein R is hydrogen or alkyl containing 1-20 carbon numbers; m is a metal element; a is an integer from 5 to 50; b is an integer from 2 to 100; z is an integer from 0 to 10; the metal-containing electrolyte can carry metal ions, has good conductivity, and has good conductivity without adding metal salts, so that the problem of possible mechanical property change due to the addition of excessive metal salts in the known solid electrolyte can be avoided.

Description

Technical Field

[0001]

[0011] Some embodiments of the present disclosure provide metal-containing electrolytes and methods of making the same. Background Art

[0002] Lithium-ion batteries (LIBs) are widely used due to their high energy density, high output voltage, and low self-discharge rate. Conventional LIBs typically use solid-state polymer electrolytes. To enhance ionic conductivity, conductive agents such as lithium salts and graphene oxide are often added. However, these additives are expensive and can alter the mechanical properties of the polymer.

[0003] Therefore, how to provide an electrolyte with good electrical conductivity without adding an external conductive agent is a problem to be solved. Summary of the Invention

[0004] Some embodiments of the present disclosure provide a metal-containing electrolyte comprising a structure of Formula 1 below:

[0005] wherein R is hydrogen or an alkyl group containing 1 to 20 carbon atoms;

[0006] M is a metal element;

[0007] a is an integer from 5 to 50;

[0008] b is an integer from 2 to 100;

[0009] z is an integer from 0 to 10.

[0010] In some embodiments, M is an element from Group 1 of the Periodic Table of Elements.

[0011] In some embodiments, the metal-containing electrolyte has the structure of Formula 2 or Formula 3 below: wherein a is an integer from 5 to 50; and b is an integer from 2 to 100.

[0012] In some embodiments, the metal-containing electrolyte further comprises an alkali metal salt.

[0013] In some embodiments, the alkali metal salt comprises lithium bis(fluorosulfonylimide), potassium bis(fluorosulfonylimide), lithium bis(trifluoromethanesulfonylimide), potassium bis(trifluoromethanesulfonylimide), or a combination thereof.

[0014] In some embodiments, the weight ratio of the metal-containing electrolyte to the alkali metal salt is from 5:95 to 95:5.

[0015] Some embodiments of the present disclosure provide methods for manufacturing a metal-containing electrolyte, comprising: providing a siloxane polymer, polyethylene glycol methyl ether methacrylate, and an olefinic acid compound; mixing the siloxane polymer, polyethylene glycol methyl ether methacrylate, and the olefinic acid compound in an organic solvent to obtain a first mixed solution; heating the first mixed solution so that the alkenyl groups of the polyethylene glycol methyl ether methacrylate and the alkenyl groups of the olefinic acid compound undergo hydrosilylation reactions with the silicon-hydrogen bonds of the siloxane polymer, respectively, to form an initial electrolyte, thereby obtaining a first reaction solution containing the initial electrolyte; providing a metal compound; mixing the metal compound with the first reaction solution to obtain a second mixed solution; and heating the second mixed solution so that metal ions in the metal compound ionic bonds with oxygen of hydroxyl groups in the initial electrolyte to obtain a metal-containing electrolyte.

[0016] In some embodiments, the silicone polymer comprises polydimethylsiloxane.

[0017] In some embodiments, the olefinic compound comprises acrylic acid, carboxyethyl acrylate, or a combination thereof.

[0018] In some embodiments, in the step of mixing the siloxane polymer, polyethylene glycol methyl ether methacrylate, and the olefinic acid compound in the organic solvent, the molar ratio of the siloxane polymer to the polyethylene glycol methyl ether methacrylate is 1:5 to 5:1.

[0019] In some embodiments, in the step of mixing the siloxane polymer, polyethylene glycol methyl ether methacrylate, and the olefinic acid compound in an organic solvent, the molar ratio of the polyethylene glycol methyl ether methacrylate to the olefinic acid compound is 1:5 to 5:1.

[0020] In some embodiments, the organic solvent comprises tetrahydrofuran, n-hexane, or a combination thereof.

[0021] In some embodiments, the step of mixing the siloxane polymer, polyethylene glycol methyl ether methacrylate, and the acrylate compound in the organic solvent includes adding platinum.

[0022] In some embodiments, the step of heating the first mixed liquid comprises heating the first mixed liquid at 70° C. to 90° C. in an environment containing an inert gas.

[0023] In some embodiments, the metal compound comprises a metal ion from Group 1, Group 2 of the Periodic Table of Elements, or a combination thereof.

[0024] In some embodiments, in the step of mixing the metal compound with the first reaction solution, the molar ratio of the olefinic acid compound to the metal compound is 1:20 to 20:1.

[0025] In some embodiments, the step of heating the second mixed liquid comprises heating the second mixed liquid at 70° C. to 90° C. in an environment containing an inert gas.

[0026] In some embodiments, the step of heating the second mixed solution includes mixing a metal-containing electrolyte with an alkali metal salt.

[0027] In some embodiments, the weight ratio of the metal-containing electrolyte to the alkali metal salt is from 5:95 to 95:5.

[0028] In some embodiments, the alkali metal salt comprises lithium bis(fluorosulfonylimide), potassium bis(fluorosulfonylimide), lithium bis(trifluoromethanesulfonylimide), potassium bis(trifluoromethanesulfonylimide), or a combination thereof.

[0029] It is to be understood that both the foregoing general description and the following detailed description are examples, and are intended to provide further explanation of the disclosure as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] To make the above and other objects, features, advantages and embodiments of the present invention more apparent, the detailed description of the accompanying drawings is as follows:

[0031] Figure 1 A flow chart of a method for manufacturing a metal-containing electrolyte according to some embodiments of the present application;

[0032] Figure 2 In an embodiment illustrating the present disclosure, charge-discharge cycle tests were performed on half-cell systems comprising solid electrolytes of the AAM950 group and the CEAM950 group. The relationship between specific capacitance and coulombic efficiency and the number of cycles of each half-cell system was compared over multiple charge-discharge cycles.

[0033] Figure 3 In an embodiment illustrating the present disclosure, charge-discharge cycling tests were performed on half-cell systems comprising a solid electrolyte system composed of either an AAM950 or CEAM950 and a liquid electrolyte (EC:PC:DEC system). The relationship between potential and specific capacitance was compared across multiple charge-discharge cycles for each half-cell system.

[0034] Figure 4A as well as Figure 4B In the examples of the present disclosure, the potassium salt group ( Figure 4A ) or lithium salt group ( Figure 4B ) solid electrolyte half-cell system, performing charge-discharge cycle tests, and comparing the relationship between potential and specific capacitance of each half-cell system during multiple charge-discharge cycles;

[0035] Figure 5AIn an embodiment of the present disclosure, charge-discharge cycle tests were performed on half-cell systems containing solid electrolytes of different types and contents of lithium salts. The relationship between specific capacitance and coulombic efficiency and the number of cycles was compared for each half-cell system over multiple charge-discharge cycles.

[0036] Figure 5B In an embodiment illustrating the present disclosure, charge-discharge cycling tests were conducted on half-cell systems comprising solid electrolytes containing CEAM950 and a lithium salt (LiTFSI) at varying weight ratios. The relationship between specific capacitance and coulombic efficiency versus cycle number was compared for each half-cell system over multiple charge-discharge cycles.

[0037]

Explanation of symbols

[0038] 100: Method

[0039] S110, S120, S130, S140, S150, S160: Steps DETAILED DESCRIPTION

[0040] It will be appreciated that the following content provides different embodiments or examples that may implement different features of the subject matter of the present disclosure. The examples of specific components and arrangements are intended to simplify the present disclosure and are not intended to limit the present disclosure. Of course, these are merely examples and are not intended to be limiting. For example, the description below of a first feature being formed on a second feature includes the two being in direct contact, or the two being separated by other additional features rather than in direct contact. In addition, the present disclosure may repeat reference numbers and / or symbols in multiple embodiments. Such repetition is for simplicity and clarity and does not represent a relationship between the various embodiments and / or configurations discussed.

[0041] The terms used in this specification generally have their ordinary meanings in the art and in the context in which they are used. The examples used in this specification, including examples of any term discussed herein, are illustrative only and do not limit the scope and meaning of the present disclosure or any exemplary term. Similarly, the present disclosure is not limited to the embodiments provided in this specification.

[0042] It will be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. For example, without departing from the scope of this embodiment, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0043] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0044] As used herein, the terms "include", "comprising", "having" and the like should be understood as open ended, that is, meaning including but not limited to.

[0045] Please refer to Figure 1 Some embodiments of the present disclosure provide a method 100 for manufacturing a metal-containing electrolyte, comprising steps S110 to S160.

[0046] The method 100 forms an ionic bond between metal ions of a metal compound and oxygen of hydroxyl groups in an initial electrolyte (eg, a pre-lithiation process) to obtain a metal-containing electrolyte capable of carrying metal ions.

[0047] Compared to conventional polymer electrolytes, metal-containing electrolytes carrying metal ions have better electrical conductivity. Furthermore, because they can achieve good electrical conductivity without the addition of metal salts, they avoid the mechanical property changes (e.g., excessive hardness or softness) that can occur in conventional solid-state electrolytes due to the addition of excessive metal salts.

[0048] First, referring to step S110 , a siloxane polymer, poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) and an olefinic acid compound are provided.

[0049] In some embodiments, the siloxane polymer comprises polymethylhydrosiloxane (PMHS). In some embodiments, one PEGMEMA comprises 2 to 100 repeating -CH2-CH2-O- segments. In some embodiments, the olefinic acid compound comprises an organic acid having an olefinic group and a carboxyl group, such as acrylic acid (AA), carboxyethyl acrylate (CEA), or a combination thereof.

[0050] In step S120 , a siloxane polymer, polyethylene glycol methyl ether methacrylate (PEGMEMA), and an acrylate compound are mixed in an organic solvent to obtain a first mixed solution.

[0051] In some embodiments, the organic solvent comprises tetrahydrofuran (THF), n-hexane, or a combination thereof. Compared to other organic solvents, siloxane polymers, PEGMEMA, and olefinic acid compounds have better solubility in THF.

[0052] In some embodiments, during the step of mixing the siloxane polymer, PEGMEMA, and the olefinic acid compound in an organic solvent, the molar ratio of the siloxane polymer to the PEGMEMA is 1:5 to 5:1, for example, 1:5, 2:5, 3:5, 4:5, 1:1, 2:1, 3:1, 4:1, 5:1, or values ​​in between. If the molar ratio is too high or too low, the efficiency of the subsequent bonding reaction is limited.

[0053] In some embodiments, during the step of mixing the siloxane polymer, PEGMEMA, and the olefinic acid compound in an organic solvent, the molar ratio of PEGMEMA to the olefinic acid compound is 1:5 to 5:1, for example, 1:5, 2:5, 3:5, 4:5, 1:1, 2:1, 3:1, 4:1, 5:1, or values ​​in between. If the molar ratio is too high or too low, the efficiency of the subsequent bonding reaction is limited.

[0054] In some embodiments, the step of mixing the siloxane polymer, PEGMEMA, and the olefinic acid compound in the organic solvent includes adding platinum. It is understood that platinum can act as a catalyst to improve the efficiency of subsequent bonding.

[0055] In step S130 , the first mixed solution is heated to allow the alkenyl groups of PEGMEMA and the alkenyl groups of the olefinic acid compound to undergo hydrosilylation reactions with the silicon-hydrogen bonds of the siloxane polymer to form an initial electrolyte, thereby obtaining a first reaction solution containing the initial electrolyte.

[0056] Specifically, PEGMEMA undergoes a hydrosilylation reaction with the silicon-hydrogen bond of the siloxane polymer via the alkenyl group, thereby replacing the hydrogen of the silicon-hydrogen bond and bonding to the siloxane polymer. The olefinic acid compound undergoes a hydrosilylation reaction with another silicon-hydrogen bond in the siloxane polymer via the alkenyl group, thereby replacing the hydrogen of the silicon-hydrogen bond and bonding to the siloxane polymer. It is worth emphasizing that by selecting PEGMEMA and olefinic acid compounds with carbonyl groups (C=O) and bonding them to the siloxane polymer respectively, it can be ensured that the subsequent metal-containing electrolyte contains carbonyl groups (C=O), thereby giving the metal-containing electrolyte the property of attracting metal ions to improve conductivity. In some embodiments, olefinic acid compounds with different numbers of carbonyl groups can also be selected as needed to adjust the conductivity of the metal-containing electrolyte.

[0057] In some embodiments, step S130 includes heating the first mixed liquid at 70°C to 90°C in an environment containing an inert gas, for example, 70°C, 75°C, 80°C, 85°C, 90°C, or values ​​in between. If the temperature is too high, the alkenyl groups of PEGMEMA and the alkenyl groups of the olefinic acid compound may polymerize first, resulting in a decrease in reactivity with the siloxane polymer and a product structure that is different from the expected; if the temperature is too low, the reaction efficiency is limited. In addition, by using an inert gas, air can be isolated from entering, preventing the generation of other impurities and ensuring the smooth progress of the reaction. In some embodiments, the inert gas comprises nitrogen, argon, helium, or a combination thereof.

[0058] Please see step S140 , providing a metal compound.

[0059] In some embodiments, the metal compound comprises a metal ion from Group 1, Group 2, or a combination thereof of the periodic table. In some embodiments, the metal compound is a metal salt having a degree of dissociation greater than 50% in an organic solvent, wherein the metal is from Group 1, Group 2, or a combination thereof of the periodic table. In some embodiments, the metal compound comprises lithium hydroxide, potassium hydroxide, lithium carbonate, potassium carbonate, lithium phosphate, lithium sulfate, lithium nitrate, or a combination thereof. Depending on the battery performance requirements, a metal compound with a suitable metal ion can be selected for subsequent ionic bonding reactions (e.g., pre-lithiation treatment).

[0060] Please see step S150 , the metal compound is mixed with the first reaction solution to obtain a second mixed solution.

[0061] In some embodiments, the molar ratio of the olefinic acid compound to the metal compound in step S150 is from 1:20 to 20:1, for example, 1:20, 1:15, 1:10, 1:5, 1:1, 5:1, 10:1, 15:1, 20:1, or values ​​in between. A high molar ratio may increase polymer viscosity, while a low molar ratio may limit the reaction efficiency of the metal ion and the olefinic acid compound.

[0062] In step S160 , the second mixed solution is heated to allow the metal ions in the metal compound to form ionic bonds with the oxygen of the hydroxyl groups in the initial electrolyte, thereby obtaining a metal-containing electrolyte.

[0063] In some embodiments, step S160 includes heating the second mixed liquid in an inert gas atmosphere at a temperature between 70°C and 90°C, such as 70°C, 75°C, 80°C, 85°C, 90°C, or values ​​therebetween. Because the features here are similar to those of step S130 , they are not further described here.

[0064] In some embodiments, the metal-containing electrolyte has the structure of Formula 1:

[0065]

[0066] wherein R is hydrogen or an alkyl group having 1 to 20 carbon atoms (e.g., 1, 5, 10, 15, 20 carbon atoms, or carbon atoms in between);

[0067] M is a metal element (e.g., an element from Group 1 of the periodic table, for example, lithium, sodium, potassium, rubidium, cesium, or mesorium);

[0068] a is an integer from 5 to 50 (e.g., 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, or an integer therebetween);

[0069] b is an integer from 2 to 100 (e.g., 2, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, or an integer therebetween);

[0070] z is an integer from 0 to 10 (eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or an integer therebetween).

[0071] Please refer to Formula 1. The hydroxyl group of the initial electrolyte is part of the carboxyl group (the carboxyl group here corresponds to the carboxyl group of the olefinic acid compound in the previous reactant). In step 160, the metal ion replaces the hydrogen in the carboxyl group of the initial electrolyte and forms an ionic bond with the oxygen in the carboxyl group. In addition, the lithium-containing electrolyte also has a carbonyl group (C=O). Therefore, in addition to ionic bonding, it can also carry metal ions in a non-bonding manner, so that the metal-containing electrolyte can carry multiple metal ions by itself and dissociate under appropriate conditions for conductivity (at this time, the anionic segment (such as COO - ) can provide a base for metal ion conduction, improving electrical conductivity. Therefore, the larger the z in Formula 1, the more carbonyl groups there are, and the more metal ions can be carried.

[0072] Therefore, since the lithium-containing electrolyte itself contains conductive metal ions, it is unnecessary to add additional metal salts (but it can still be added selectively), which can avoid the problem of mechanical property changes (such as excessive hardness or softness) caused by the addition of excessive metal salts in conventional solid electrolytes.

[0073] In some embodiments, by selecting different olefinic acid compounds, a metal-containing electrolyte having the following formula 2 (the reactant includes AA) or formula 3 (the reactant includes CEA) can be obtained:

[0074]

[0075] wherein a is an integer from 5 to 50;

[0076] b is an integer from 2 to 100.

[0077] In some embodiments, after step S160, the step further includes mixing a metal-containing electrolyte with an alkali metal salt. The addition of the alkali metal salt further enhances the electrical conductivity.

[0078] In some embodiments, the weight ratio of the metal-containing electrolyte to the alkali metal salt is 5:95 to 95:5, for example, 5:95, 1:9, 1:3, 1:1, 3:1, 9:1, 95:5, or values ​​in between the foregoing ranges. If the weight ratio is too large, the improvement in conductivity is limited, and if the weight ratio is too small, the mechanical properties of the metal-containing electrolyte may be changed.

[0079] In some embodiments, the alkali metal salt includes lithium bis(fluorosulfonyl)imide (LiFSi), potassium bis(fluorosulfonyl)imide (KFSi), lithium bis(trifluoromethanesulfonyl)imide (LiTFSi), potassium bis(trifluoromethanesulfonyl)imide (KTFSi), or a combination thereof. By releasing lithium ions, the electrical conductivity can be enhanced.

[0080] A series of examples of metal-containing electrolytes, manufacturing methods, and conditional testing of metal-containing electrolytes are provided below to illustrate some embodiments of the present disclosure.

[0081] Example 1: Method for manufacturing a metal-containing electrolyte

[0082] 1. Synthesis of AAM950 (addition of AA)

[0083] The reaction formula of AAM950 can be expressed as the following reaction formula 1:

[0084]

[0085] The specific process is as follows:

[0086] First, 0.99 g of polydimethylsiloxane (PMHS) [0.0165 mol, wherein n in Reaction Formula 1 is 25-50], 12.825 g of polyethylene glycol methyl ether methacrylate (PEGMEMA, wherein m in Reaction Formula 1 is 19-20) [0.0135 mol], and 0.108 g of acrylic acid (AA) [0.0015 mol] were added to a flask, wherein PMHS:PEGMEMA:AA = 1.1:0.9:0.1.

[0087] Next, the flask was placed in a silicone oil bath and stirred at 60±2°C and 100±5 rpm (revolutions per minute) until the above materials were uniformly dispersed. Approximately 150 ml of tetrahydrofuran (THF) as a solvent and a drop of platinum as a catalyst were added to form a first mixed solution.

[0088] The first mixed liquid was transferred into a condensation system, and an appropriate amount of nitrogen was introduced into the reaction bottle containing the first mixed liquid to isolate the air; the mixture was then heated to 80±2°C and stirred at 110±5 rpm for 78 hours to allow the alkenyl groups of PEGMEMA and AA to undergo hydrosilylation reactions with the silicon-hydrogen bonds of PMHS, respectively, to form an initial electrolyte, thereby obtaining a first reaction liquid having an initial electrolyte.

[0089] Next, 0.005 mol of lithium hydroxide hydrate (LiOH·nH2O) was added to the first reaction solution to obtain a second mixed solution. An appropriate amount of nitrogen was introduced into the reaction flask of the second mixed solution to isolate the air. The second mixed solution was then heated to 80±2°C and stirred at 110±5 rpm for 24 hours to allow the Li+ in the LiOH to ionically bond with the oxygen of the hydroxyl groups of the initial electrolyte (replacing the hydrogen in the hydroxyl groups, a pre-lithiation reaction). Thus, a lithium-containing electrolyte having a structure of Formula 2 (hereinafter referred to as AAM950) was obtained in the heated second mixed solution.

[0090] In addition, although not shown in the figure, it can be understood that since the carbonyl group (C=O) has a high dipole property, it also has a high attraction for Li ions. Therefore, in the lithium-containing electrolyte obtained by the pre-lithiation reaction, each carbonyl group (C=O) has Li+ attracted in a non-ionic bonding manner, which can give the lithium-containing electrolyte better conductivity.

[0091] Next, the condensation system was removed, and residual salts were removed via vacuum filtration. The THF was then removed using a low-temperature vacuum cyclone concentrator, yielding a viscous slurry (containing the lithium-containing electrolyte of Formula 2). The slurry was then purified three times with n-hexane and then placed in a vacuum oven at 70°C for 24 hours to remove residual solvent, yielding AAM950.

[0092] 2.CEAM950

[0093] The reaction formula of CEAM950 can be expressed as the following reaction formula 2:

[0094]

[0095] The manufacturing process for CEAM950 is essentially similar to that for AAM950. The difference between the two is that the 0.108 g of AA (0.0015 mol) added in Reaction 1 of AAM950 is replaced with 0.216 g of carboxyethyl acrylate (0.0015 mol) in Reaction 2 of CEAM950. Following Reaction 2, a lithium-containing electrolyte having the structure of Formula 3 (hereinafter referred to as CEAM950) is obtained.

[0096] Based on the description of Formula 2, although not shown in the figure, it can be understood that each carbonyl group (C=O) in Formula 3 has Li+ attracted in a non-ionic bonding manner, which can give the lithium-containing electrolyte better conductivity.

[0097] Example 2: Comparison of the performance of pre-lithiation and added lithium salt

[0098] To compare the effects of pre-lithiation or lithium salt addition on the conductivity and activation energy of solid electrolytes, first, solid electrolyte 1 without pre-lithiation and lithium salt addition, solid electrolyte 2 without pre-lithiation but with lithium salt addition, and solid electrolyte 3 with pre-lithiation and lithium salt addition were prepared.

[0099] Preparation method of solid electrolyte 1: The raw materials and contents are the same as those in Example 1, but the first reaction solution contains PMHS, PEGMEMA, CEA, and LiOH, and does not undergo a subsequent pre-lithiation step of heating at 80°C. Therefore, there is no ionic bonding between Li+ in solid electrolyte 1 and PMHS, PEGMEMA, and CEA.

[0100] That is, the solid electrolyte 1 contains the initial electrolyte+LiOH.

[0101] That is, solid electrolyte 1 is CEAM950 (unlithiated) + 0M LiFSI.

[0102] Preparation method of solid electrolyte 2: The method is the same as that of solid electrolyte 1, but LiFSI is additionally added to make the concentration of LiFSI 1M to help conductivity.

[0103] That is, the solid electrolyte 2 includes the initial electrolyte + LiOH + 1M LiFSI. In other words, the solid electrolyte 2 is CEAM950 (unlithiated) + 1M LiFSI.

[0104] Preparation method of solid electrolyte 3: After obtaining CEAM950 using the same method as Example 1 (with pre-lithiation), LiFSI is additionally added to make the concentration of LiFSI 1M to facilitate conductivity.

[0105] That is, the solid electrolyte 3 comprises CEAM950 (lithiated electrolyte) + 1M LiFSI. In other words, the solid electrolyte 3 is CEAM950 (lithiated) + 1M LiFSI.

[0106] Next, each set of solid electrolytes (solid electrolyte 1, solid electrolyte 2, and solid electrolyte 3) was placed in a Teflon container containing two 304 stainless steel electrodes, with the solid electrolyte covering the stainless steel electrodes. The Teflon container was then placed in an oven. The Arrhenius equation was used to calculate the ionic conductivity and activation energy of each solid electrolyte set at various temperatures between 303K and 363K. The results are summarized in Table 1.

[0107] Table 1

[0108]

[0109] Table 1 shows that the addition of a lithium salt (LiFSI) can improve conductivity and activation energy (see the comparison of solid electrolyte 1 and solid electrolyte 2). Pre-lithiation of the solid electrolyte can also improve conductivity (see the comparison of solid electrolyte 2 and solid electrolyte 3).

[0110] Example 3: Performance of AAM950 and CEAM950

[0111] 1. Conductivity and activation energy of AAM950 and CEAM950

[0112] To compare the conductivity and activation energy of AAM950 and CEAM950, a method similar to Example 2 was used, first increasing the temperature and then decreasing the temperature. The conductivity and activation energy of the AAM950 group and the CEAM950 group were compared. The results are summarized in Table 2.

[0113] In addition, in addition to AAM950 or CEAM950, each group also added the same concentration of LiFSI (1.2M LiFSI in AAM950 or CEAM950) to improve conductivity and facilitate observation.

[0114] Table 2

[0115]

[0116]

[0117] The results in Table 2 show that the AAM950 group and the CEAM950 group have similar performance, both with good conductivity and low activation energy.

[0118] 2. Electrochemical testing of AAM950 and CEAM950 groups

[0119] To further test the electrochemical performance of AAM950 and CEAM950 when prepared as batteries, the electrochemical performance of AAM950 group and CEAM950 group was tested in a half-cell system, in which the active material of the working electrode was LiNi 0.8 Mn 0.1 Co 0.1 O2 (abbreviated as NCM811), aluminum foil is used as the current collecting layer, lithium foil is used as the auxiliary electrode, and the solid electrolyte is the AAM950 group (AAM950+1.2M LiFSI) or CEAM950 group (CEAM950+1.2MLiFSI) mentioned in the first point above.

[0120] The specific steps are as follows:

[0121] A solid electrolyte material of AAM950+1.2M LiFSI or CEAM950+1.2M LiFSI was mixed with an anhydrous oily solvent (which could be N-methylpyrrolidone (NMP), acetone, or a 1:1 mixture of NMP and acetone) at a ratio of 1.34 g:20 ml, and then stirred at 600 rpm for 10 minutes to obtain a solid electrolyte solution.

[0122] The solid electrolyte solution and the active material (NCM811) were mixed at a weight ratio of 1.34:9 to obtain an electrode mixture. The mixture was stirred at 900 rpm for 10 minutes and then placed in a 60° C. oven to remove the anhydrous oily solvent.

[0123] Next, the electrode mixture was sieved through a 400-mesh screen to ensure that the active material was not excessively agglomerated. It was then placed in a 90°C vacuum oven for 30 minutes to ensure that the anhydrous oily solvent was completely removed, allowing the active material to coat the solid electrolyte material.

[0124] The active material, conductive carbon, and a binder solution (6% polyvinylidene fluoride dissolved in N-methylpyrrolidone) were mixed in a weight ratio of 90:5:5 to obtain an electrode slurry.

[0125] After the electrode slurry is evenly coated on an aluminum foil with a thickness of 200 μm, the wet electrode is placed in an 80°C vacuum oven for 1 hour to dry it into a dry electrode, and then cut into a circular electrode piece with a diameter of 12 mm to obtain a working electrode impregnated with a solid electrolyte.

[0126] A half-cell system was prepared by combining a solid electrolyte-impregnated working electrode (the solid electrolyte comprising the AAM950 group (AAM950 + 1.2M LiFSI) or the CEAM950 group (CEAM950 + 1.2M LiFSI) described in point 1 above) with an auxiliary electrode (lithium foil). Next, a charge-discharge cycle test was performed at 60°C with a current density of 0.1 coulomb (C) for 25 cycles (one cycle was defined as a voltage from 2.8 volts to 4.3 volts). The relationship between the specific capacitance and coulombic efficiency during the charge-discharge process and the number of cycles was measured. The results are shown in the table. Figure 2 .

[0127] Figure 2 The results show that the specific capacitance and coulombic efficiency of the AAM950 and CEAM950 groups are generally similar. At the 25th cycle, the specific capacitance of the AAM950 group is slightly higher than that of the CEAM950 group, while the coulombic efficiency of the CEAM950 group is slightly higher than that of the AAM950 group.

[0128] 3. Comparison of electrochemical performance between solid electrolytes (AAM950 group and CEAM950 group) and liquid electrolytes

[0129] To compare the electrochemical performance of the solid electrolytes of the AAM950 group (with added lithium salt) and the CEAM950 group (with added lithium salt) in the first point above and the liquid electrolyte (mixed with 30 parts by volume of ethylene carbonate (EC) + 20 parts by volume of propylene carbonate (PC) + 50 parts by volume of diethyl carbonate (DEC), referred to as the EC:PC:DEC group), a half-cell system was prepared in a manner similar to that in the second point of Example 3 (the only difference was that the active material of the working electrode was LiNi 0.6 Co 0.2 Mn 0.2 O2 (NCM622)), at room temperature, conduct charge and discharge tests to observe the relationship between the potential and specific capacitance of each half-cell system during charging. Figure 3 .

[0130] Specifically, the charging step involved discharging to 2.8V at a current density of 0.1C. Each group then charged using a constant current-constant voltage procedure, with a voltage range of 2.8V to 4.3V. The discharging step involved charging to 4.3V at a current density of 0.1C, followed by discharging from 4.3V to 2.8V. Furthermore, a control group was designed for the EC:PC:DEC group, which was charged only to 4.0V.

[0131] Figure 3 It is shown that compared with the liquid electrolyte (EC:PC:DEC group), the solid electrolyte group (AAM950 group and CEAM950 group) has electrochemical properties similar to those of the liquid electrolyte.

[0132] Compared to liquid electrolytes, solid electrolytes have advantages such as higher safety and ease of miniaturization. Therefore, the solid electrolyte test examples (AAM950 group and CEAM950 group) disclosed in this disclosure are applied to batteries. While exhibiting electrochemical performance similar to that of liquid electrolytes, they are more conducive to miniaturization development and have higher safety.

[0133] At the same time, the discharge capacitance and reversibility after the first cycle of charge and discharge (initial discharge capacitance / initial charge capacitance x 100%, initial coulombic efficiency) were observed, and the irreversibility (100% - reversibility) was calculated accordingly. The results are shown in Table 3 below.

[0134] Table 3

[0135]

[0136] Table 3 shows that the CEAM950 group has a lower irreversibility rate compared to the liquid electrolyte.

[0137] Example 4: Comparison of Added Potassium Salt or Added Lithium Salt

[0138] Furthermore, in order to test the electrochemical performance of the battery when metal-containing electrolytes (added alkali metal salts) with different types of alkali metal salts are used as solid electrolytes, the electrochemical performance of the corresponding potassium ion half-cell or lithium ion half-cell is compared in the half-cell system when the solid electrolyte contains potassium salt or lithium salt respectively.

[0139] The active material of the working electrode is a mixture of graphite, carbon black (super P), and polyvinylidene fluoride (PVDF). The current collector layer is made of copper foil. The auxiliary electrode is made of lithium foil or potassium foil (the choice depends on the solid electrolyte; for example, when the solid electrolyte contains potassium salt, potassium foil is used). The solid electrolyte includes a potassium salt combination (CEAM950 + 1M KFSI) and a lithium salt combination (CEAM950 + 1M LiFSI).

[0140] The specific preparation method of the half-cell is as follows:

[0141] The active material coating for the working electrode, graphite, carbon black (super P), and polyvinylidene fluoride (PVDF), was mixed in NMP at a weight ratio of 90:5:5 and dried in a vacuum oven at 80°C for 12 hours. The active material coating was then coated and pressed onto a copper foil sheet, which was then cut to the appropriate size to form the working electrode.

[0142] After obtaining the working electrode, the working electrode was paired with a solid electrolyte and an auxiliary electrode to prepare a potassium ion half-cell (auxiliary electrode: potassium foil; solid electrolyte: CEAM950+1M KFSI) and a lithium ion half-cell (auxiliary electrode: lithium foil; solid electrolyte: CEAM950+1M LiFSI), respectively.

[0143] Next, at 60°C, the potassium ion half-cell and lithium ion half-cell were subjected to 200 charge-discharge cycle tests (3.0V to 0.01V voltage meter as one cycle) at a current density of 0.1C. The relationship between the potential and specific capacitance during the charge-discharge process was detected. The results are shown in Figure 2. Figure 4A (potassium ion half-cell-potassium salt group) and Figure 4B (Lithium-ion half-cell - lithium salt group).

[0144] Figure 4A as well as Figure 4B It is shown that regardless of whether the solid electrolyte contains potassium salt or lithium salt, the half-cell exhibits stable electrochemical performance.

[0145] Furthermore, the comparison Figure 4A as well as Figure 4B It can be observed that the potassium ion half-cell and the lithium ion half-cell show different battery capacity performance (specific capacitance) and electrochemical voltage reaction (potential) feedback phenomena. Taking the second cycle as an example, Figure 5A In the potassium-ion half-cell, the plateau reaction is not obvious between 0.5 volts and 1 volt, indicating that potassium ions do not contribute to the reaction during this period. In contrast, the plateau reaction in the lithium-ion half-cell is obvious and prolonged, indicating that lithium ions assist the reaction at this point. Therefore, the different ionic conductivity of the two ions in the solid electrolyte gives the battery different performance characteristics.

[0146] Example 5: Conditional test of the type and ratio of added lithium salt

[0147] 1. Lithium salts of different types and contents

[0148] To further test whether the solid electrolyte prepared by combining CEAM950 with lithium salts of different types or ratios (LiFSI, LiTFSI, or a mixture of the two) would result in differences in battery electrochemical performance, a half-cell system was prepared in a manner similar to that described in Example 3, point 2, and electrochemical testing was performed to examine the relationship between specific capacitance and coulombic efficiency during charge and discharge and the number of cycles. The results are shown in Figure 2. Figure 5A .

[0149] Specifically, the main difference between the half-cell system here and the half-cell system of Example 3, point 2, is that the solid electrolyte is changed to a 1.2M LiFSI group (including CEAM950 and 1.2M LiFSI), a 0.6M LiFSI+0.6M LiTFSI group (including CEAM950, 0.6M LiFSI and 0.6M LiTFSI), or a 1.2M LiTFSI group (including CEAM950 and 1.2M LiTFSI).

[0150] Figure 5A The results show that the 1.2M LiTFSI group maintained a higher specific capacitance than the 0.6M LiFSI + 0.6M LiTFSI group and the 1.2M LiTFSI group at the 30th cycle. Furthermore, the Coulombic efficiency of each group remained above 95% at the 30th cycle, with no significant fluctuation in Coulombic efficiency between cycles, demonstrating the high stability of each battery group.

[0151] Therefore, by comparing the 1.2M LiFSI group, the 0.6M LiFSI+0.6M LiTFSI group and the 1.2M LiTFSI group, it can be found that when the lithium salt is the LiTFSI group, the battery has better electrochemical performance.

[0152] 2. Lithium-containing electrolyte and lithium salt at different weight ratios

[0153] To further test whether the difference in electrochemical performance of the battery would occur when metal-containing electrolytes containing different weight ratios of CEAM950 and lithium salt (LiTFSI) were prepared as solid electrolytes, a half-cell system was prepared in a manner similar to that of Example 3, point 2, and electrochemical tests were performed to detect the relationship between the specific capacitance and coulombic efficiency during the charge and discharge process and the number of cycles. The results are shown in FIG. Figure 5B .

[0154] Specifically, the primary difference between this half-cell system and the half-cell system described in Example 3, Section 2, is that electrochemical testing was performed using three solid electrolyte combinations: CEAM959 and 1.2M LiTFSI in a weight ratio of 10:90, 30:70, or 50:50, respectively. Specifically, in the 10:90 combination, the solid electrolyte contained 1.2M LiTFSI, and the weight ratio of CEAM959 to LiTFSI was 10:90.

[0155] Figure 5B The results show that compared to the 30:70 and 50:50 groups, the 10:90 group maintained a higher specific capacitance after the fifth cycle (the 50:50 group was second, and the 30:70 group was last). Furthermore, at the 20th cycle, the coulombic efficiency of each group remained above 95%, with no significant fluctuations between cycles, demonstrating the high stability of each battery group.

[0156] Therefore, by comparing the solid electrolyte performance of the three groups of 10:90, 30:70, and 50:50, it can be found that when the weight ratio of CEAM959 to LiTFSI is 10:90, the battery has better electrochemical performance.

[0157] Although the present disclosure has been described in detail with reference to certain embodiments, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the embodiments described herein.

Claims

1. A metal-containing electrolyte, characterized in that Contains the structure of the following formula 1: wherein R is hydrogen or an alkyl group containing 1 to 20 carbon atoms; M is a metal element; a is an integer from 5 to 50; b is an integer from 2 to 100; z is an integer from 0 to 10.

2. The metal-containing electrolyte according to claim 1, wherein The metal-containing electrolyte has the structure of the following formula 2 or formula 3: wherein a is an integer from 5 to 50; b is an integer from 2 to 100.

3. The metal-containing electrolyte according to claim 1, wherein Also included are alkali metal salts.

4. The metal-containing electrolyte according to claim 3, wherein The alkali metal salt comprises lithium bis(fluorosulfonyl)imide, potassium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide or a combination thereof.

5. The metal-containing electrolyte according to claim 3, wherein The weight ratio of the metal-containing electrolyte to the alkali metal salt is 5:95 to 95:

5.

6. A method for producing a metal-containing electrolyte, characterized in that Include: Provide silicone polymers, polyethylene glycol methyl ether methacrylate and olefinic acid compounds; Mixing the siloxane polymer, the polyethylene glycol methyl ether methacrylate, and the olefinic acid compound in an organic solvent to obtain a first mixed solution; Heating the first mixed solution to allow the alkenyl groups of the polyethylene glycol methyl ether methacrylate and the alkenyl groups of the olefinic acid compound to undergo hydrosilylation reactions with the silicon-hydrogen bonds of the siloxane polymer, respectively, to form an initial electrolyte, thereby obtaining a first reaction solution containing the initial electrolyte; providing a metal compound; mixing the metal compound with the first reaction solution to obtain a second mixed solution; The second mixed solution is heated to allow the metal ions in the metal compound to form ionic bonds with the oxygen of the hydroxyl groups in the initial electrolyte, thereby obtaining a metal-containing electrolyte.

7. The method according to claim 6, wherein The silicone polymer comprises polydimethylsiloxane.

8. The method according to claim 6, wherein The olefinic compound comprises acrylic acid, carboxyethyl acrylate or a combination thereof.

9. The method according to claim 6, wherein In the step of mixing the siloxane polymer, the polyethylene glycol methyl ether methacrylate and the olefinic acid compound in the organic solvent, the molar ratio of the siloxane polymer to the polyethylene glycol methyl ether methacrylate is 1:5 to 5:

1.

10. The method according to claim 6, wherein In the step of mixing the siloxane polymer, the polyethylene glycol methyl ether methacrylate and the olefinic acid compound in the organic solvent, the molar ratio of the polyethylene glycol methyl ether methacrylate to the olefinic acid compound is 1:5 to 5:1.

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