JP2019121603A - Electrolyte, composition used for electrolyte, and lithium battery using the same - Google Patents

Abstract

To provide a novel electrolyte which overcomes disadvantages of the prior art.SOLUTION: An electrolyte is provided. The electrolyte includes a polymer, a lithium salt, and an organic solvent. The polymer is a polymerization product of a reactive additive and an initiator. The reactive additive includes at least one amide group and at least one epoxy group or vinyl group. Also provided are a composition for the electrolyte and a battery using the electrolyte.SELECTED DRAWING: Figure 3

Description

  This application is based on and claims the priority of Taiwan Patent Application No. 106146229 filed on December 28, 2017, which is incorporated herein by reference in its entirety. Be done.

  The present disclosure relates to an electrolyte and a lithium battery using the same.

Solid electrolytes can be classified into organic electrolytes, inorganic electrolytes and organic-inorganic composite electrolytes. However, the conductivity of organic polymer solid electrolytes (eg, PEO, PAN, etc.) is low (<10 ⁻⁵ S / cm). Inorganic solid electrolytes (eg, LLZO, LLTO, LAGP, etc.) have high conductivity (about 10 ^-3 S / cm), but the interfacial resistance between the inorganic solid electrolyte and the electrode is large. In addition, conventional inorganic ceramic electrolytes are very fragile, have poor film-forming ability and mechanical properties, and can not apply continuous processes. The organic-inorganic composite electrolyte can reduce the interface resistance, but the conductivity decreases due to the addition of the organic polymer.

  Thus, a quasi-solid state electrolyte (QSSE) has emerged as a fourth type of solid electrolyte. This is such that in addition to the organic-inorganic composite electrolyte, a small amount (<5 wt%) of liquid electrolyte is added to enhance the ionic conductivity.

  However, the presence of liquid electrolyte can cause problems such as, for example, liquid leakage, flammability, short cycle life, gassing, lack of resistance to high temperatures, and the like. Also, the problem of high interface resistance of solid electrolyte still exists.

US Patent No. 6511769 U.S. Patent No. 6,749,962 US Patent Application Publication No. 2015/0072244 Taiwan Patent No. I351121 Specification Chinese Patent Application Publication No. 106797053

  One object of the present disclosure is to provide a novel electrolyte which overcomes the above mentioned drawbacks.

  In order to achieve the above and other objects, one embodiment of the present disclosure is a polymer which is a polymerization product of a reactive additive and an initiator comprising at least one amide group and at least one epoxy group or vinyl group. Provided is an electrolyte comprising a lithium salt as well as an organic solvent.

  Another embodiment of the present disclosure is a first solution comprising a reactive additive comprising at least one amide group and at least one epoxy group or vinyl group and a first organic solvent, and an initiator, lithium A composition for an electrolyte comprising a second solution comprising a salt and a second organic solvent, the first solution and the second solution being mixed to form the electrolyte. The composition is provided, wherein the solution of and the second solution are stored separately.

  Another embodiment of the present disclosure is a lithium battery including a positive electrode, a negative electrode, and an ion conductive layer disposed between the positive electrode and the negative electrode, wherein the ion conductive layer comprises the aforementioned electrolyte. provide.

  Embodiments of the present disclosure provide electrolytes that are non-combustible and free of leak concerns. Furthermore, the electrolyte provided by the present disclosure has good coatability to both the positive electrode and the negative electrode, so that the interfacial resistance between the electrolyte and the positive electrode or the negative electrode can be effectively reduced, thus The electrolyte according to the present disclosure can be used as an ion conductive layer.

  The following embodiments will be described in detail with reference to the accompanying drawings. The disclosure may be more fully understood by reference to the following detailed description and examples, taken with reference to the accompanying drawings.

It is a figure which shows the result of the charge / discharge rate (rate charge-discharge) test of the battery using the liquid electrolyte produced by the comparative example 1. FIG. FIG. 10 is a diagram showing the results of charge and discharge rate test of a battery using the pseudo solid electrolyte produced in Example 4. It is a figure which shows the result of the cycle life test of the battery using the liquid electrolyte produced by the comparative example 1, and the battery using the pseudo | simulation solid electrolyte produced in Example 4. FIG.

  As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly indicates otherwise. Is intended. The terms "comprises" and / or "comprising" as used herein identify the presence of the described features, steps, operations, elements and / or components. It will be further understood that although not excluded the presence and addition of one or more other features, steps, operations, elements, components and / or groups thereof.

  Throughout the specification, references to "one embodiment" or "an embodiment" refer to particular features, structures or characteristics described in connection with that embodiment: It is meant to be included in at least one embodiment. Thus, the appearances of the phrase "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

  One embodiment of the present disclosure provides an electrolyte comprising a polymer, a lithium salt and an organic solvent. The polymer is the polymerization product of a reactive additive and an initiator. The reactive additive comprises at least one amide group and at least one epoxy or vinyl group.

  In some embodiments, the reactive additive has an amide structure represented by Formula (I) below or includes a structure represented by Formula (II) below.

であり得る。 Here, R ¹ and R ² are each independently an unsubstituted or substituted epoxy group, amino group, alkylamino group, alkyl group, alkyl group, alkoxy group, alkenyl group, alkenyloxy group, ether group, ester group And R ³ represents an unsubstituted or substituted epoxy group, an amino group, an alkylamino group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an ether group, an ester group, An aryl group or a haloalkyl group, which may contain 1 to 9 repeating units of an amide group, and at least one of R ¹ , R ² and R ³ is an epoxy group or Contains a vinyl group. The epoxy group or vinyl group can allow the polymerization reaction to proceed. In one embodiment, for example, the amide of formula (I) is

It can be.

であり得る。 In one embodiment, when R ³ contains one repeating unit of an amide group, the amide represented by formula (I) is, for example,

It can be.

からなる構造であり得る。 In some embodiments, the structure of Formula (II) is, for example, an unsubstituted or substituted cycloalkane that is a 4 to 20 membered multi-membered ring, an aromatic carbon A repeating unit of hydrogen, an aromatic ring, a heterocyclic ring, or a plurality of the following amide groups

It may be a structure consisting of

であってよい。 Here, R ⁴ may be at least one epoxy group or a group containing a vinyl group, R ⁵ is — (CH ₂ ) _n — (n is an integer of 1 to 18), one or more of —CH ₂ - is -NR ⁴ - substituted with _{- (CH 2) n - (} n is 1 to 18 integer), or a repeating unit of 1 to 9 in the following amide group

It may be.

  For example, in some embodiments, the structure having formula (II) may specifically include, for example, the following structures, but is not limited thereto.

からなる構造を有する。 In some embodiments, the reactive additive comprises 2 to 10 repeating units of the following amide group:

It has a structure consisting of

  Such a structure is not specifically limited to these, but includes, for example, the following structures.

  It should be understood that the foregoing reactive compounds are merely exemplary and are not intended to limit the present disclosure.

  By adding a reactive additive having at least one amide group and at least one epoxy group or vinyl group, and controlling the ratio between reactive additive, initiator, lithium salt and organic solvent It should be noted that the electrolyte of the present disclosure changes from the liquid state to the colloidal state or the pseudo-solid state after the polymerization reaction with the reactive additive.

  Specifically, the amide group of the reactive additive has a negative field effect, and an organic solvent used for a liquid electrolyte (for example, propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC) And amide groups and carbonyl groups tend to attract positively charged lithium ions and to chelate lithium ions, since there is a non-covalent electron pair in the carbonyl group of common carbonate solvents such as There is. When several reactive additives with an amide group attract each other via lithium ions, the fluidity of the organic solvent molecules is reduced, which increases the viscosity of the electrolyte. In addition, since the reactive additive agent having an amide group also has an epoxy group or a vinyl group, the ring opening polymerization reaction of the epoxy group and the radical polymerization reaction of the vinyl group by the action of the initiator During this time, the viscosity of the electrolyte is further increased, and the electrolyte changes from a liquid state to a colloidal state or a quasi-solid state.

  In some embodiments, the weight percent of the reactive additive may be, for example, 5 wt% to 50 wt%, relative to the total weight of the electrolyte. For example, in some embodiments, the weight percent of the reactive additive can be, for example, 8 wt%, 10 wt%, 20 wt%, or 50 wt%, based on the total weight of the electrolyte. By controlling the addition amount of the reactive additive, the fluidity of the electrolyte can be controlled. If the amount of reactive additive is too low, the viscosity of the electrolyte can not be increased, and the liquid electrolyte can not be cured to form a quasi-solid electrolyte. If the amount of reactive additive is too high, the viscosity of the electrolyte will be too high and the ionic conductivity will be reduced to affect the performance of the cell.

In some embodiments, examples of initiators include, for example, ionic compounds that can be dissociated to give a nucleophile, peroxides or azo compounds that can generate free radicals, or primary amine compounds. It may be mentioned. In some embodiments, the ionic compound of the above _{example, CH 3 COOLi, LiOH, LiBF} 4, LiPF 6, LiClO 4, LiTFSI, LiFSI, LiAsF 6, LiSbF 6 , or a combination thereof may be mentioned. Examples of the aforementioned peroxide may include dibenzoyl peroxide (BPO) and the like. Moreover, as the above-mentioned azo compound, for example, azobisisobutyronitrile (AIBN) can be mentioned. In the present disclosure, an initiator can be used to cause the epoxy or vinyl group of the reactive additive to undergo a polymerization reaction, which results in an increase in the molecular weight and viscosity of the electrolyte.

  In some embodiments, the weight percent of the initiator can be, for example, 0.5 wt% to 15 wt%, based on the total weight of the electrolyte. If the amount of initiator is too low, the reaction rate of the polymerization reaction will be slow and it will be difficult for the reaction to proceed completely, so excess monomer reactant may be left, thereby curing the liquid electrolyte and making it a quasi-solid It can not be an electrolyte. If the amount of initiator is too high, the reaction rate of polymerization becomes too fast, the molecular chain becomes short, and a polymer having a large molecular weight is less likely to be formed, which makes it difficult to cure the electrolyte and the electrolyte has a low mechanical It will only have properties.

In some embodiments, for _{example, LiBF 4, LiPF 6, LiClO} 4, LiTFSI, include other ionic compounds capable of dissociating the LiAsF _6, LiSbF ₆ or a lithium ion (Li ⁺⁾ as the lithium salt of the aforementioned Can be

  In some embodiments, the molar concentration of lithium salt in the electrolyte can be, for example, 0.8 M to 6 M. In some embodiments, the weight percent of the lithium salt can be, for example, 5 wt% to 50 wt%, based on the total weight of the electrolyte. If the amount of lithium salt is too low, the dissociation number of anions and cations will be too low and ion conductivity will be reduced. If the amount of lithium salt is too high, the viscosity of the electrolyte will increase and likewise the ionic conductivity will decrease.

  It should be noted that in some embodiments, the initiator may be the same as the lithium salt. In other words, if the lithium salt used can also dissociate the nucleophile, such lithium salt can also play the role of an initiator for the anionic polymerization reaction. Thus, in these embodiments, the lithium salt need only be added without the addition of other initiators. In some embodiments, the initiator may be different from the lithium salt. The type of initiator depends on the functional group of the reactive additive. When the reactive additive has a vinyl group, peroxides or azo compounds are used as initiators for the free radical polymerization reaction. If the reactive additive has an epoxy group, primary amino compounds or ionic compounds can be used as initiators.

The reaction rate and reaction temperature of the polymerization reaction vary according to the various types and amounts of initiator (or lithium salt that can be used as initiator). For example, if LiBF ₄ is selected to be used as a lithium salt, LiBF ₄ can simultaneously play the role of an initiator. The polymerization reaction may be completed at room temperature (about 25-28 ° C.) after about 12 to 24 hours without heating or supplying additional energy. If LiPF ₆ is chosen to be used as a lithium salt, LiPF ₆ may also serve as an initiator, but the polymerization reaction is completed by reacting for about 5 to 10 minutes at about 90 to 100 ° C. . When LiClO _4, LiTFSI, etc. are selected to be used as a lithium salt, LiClO ₄ and LiTFSI can also serve as an initiator, but the polymerization reaction is carried out by reacting at about 170 to 180 ° C. for about 120 minutes. It is completed.

  However, as initiators, the aforementioned initiators (or lithium salts that can be used as initiators) can provide adequate polymerization reaction rates and sufficient polymerization reaction time, so that before the electrolyte cures The electrolyte may be injected and permeated into the battery in the liquid state, and then the polymerization reaction is terminated, and the coordination force formed between the lithium ion and the solvent causes the solvent to It should be understood that any initiator can be applied to the embodiments of the present disclosure as long as the colloidal state or quasi-solid electrolyte is formed by impeding flow. A technical advantage of the present disclosure is that when the electrolyte is in a liquid state, it can fully penetrate each corner of the battery to reduce the interfacial resistance between the electrolyte and the positive or negative electrode. Once the electrolyte is cured to a colloidal or quasi-solid state, there is no leakage from the battery. Also, the colloidal state or solid electrolyte formed after curing has a flash point several times higher than commercially available liquid electrolytes and is therefore not flammable, thus significantly improving the safety of lithium batteries. Thus, the electrolyte provided by the present disclosure can effectively reduce interfacial resistance and enhance the safety of lithium batteries.

  In some embodiments, the weight percent of the organic solvent can be, for example, 40 wt% to 80 wt%, based on the total weight of the electrolyte.

  In some embodiments, the aforementioned organic solvents include, for example, solvents commonly used as common liquid electrolytes, such as carbonates, sulfonates, nitriles, ethers, ethers ), Esters, fluorides or other aprotic solvents with high polarity etc. may be mentioned.

  In some embodiments, carbonates can be classified into cyclic carbonate compounds and linear carbonate compounds. Examples of cyclic carbonate compounds include ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate, vinylene Mention may be made, without limitation, of carbonates, vinyl ethylene carbonates or combinations thereof. Examples of linear carbonate compounds include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, ethyl methyl carbonate (EMC), methyl propyl carbonate, ethyl propyl carbonate, and combinations thereof It is not necessarily limited to

  In some embodiments, the ether may include, for example, but is not limited to, dimethyl ether, diethyl ether, dipropyl ether, methyl ethyl ether, methyl propyl ether, ethyl propyl ether, combinations thereof, and the like. Absent.

  In some embodiments, esters include, for example, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, γ-valerolactone, γ-caprolactone, σ-valerolactone, ε-caprolactone Or combinations thereof, but is not limited to them.

In some embodiments, the electrolyte provided by the present disclosure may further include an inorganic electrolyte. In some embodiments, inorganic ceramic electrolytes include, for example, lithium lanthanum zirconium oxide (LLZO), tantalum doped lithium lanthanum zirconium oxide (tantalum doping lithium lanthanum zirconium oxide, LLZTO), lithium lanthanum titanium oxide (Lithium lanthanum titanium oxide, LLTO), lithium aluminum titanium phosphate (LATP), aluminum titanium phosphate (germanium aluminum titanium phosphate, LAGP), lithium germanium phosphorus sulfide (lithium phosphide sulfide, LGPS) Or lithium tin phosphorous sulfide (LSPS) and the like. For example, as inorganic ceramic electrolytes, Li ₇ La ₃ Zr ₂ O ₁₂ , Li _6.75 La ₃ Zr _1.75 Ta _0.25 O ₁₂ , Li _0.33 La _0.56 TiO ₃ , Li _1.3 Al _0.3 Ti _1.7 (PO ₄ ) ₃ , Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ , Li ₁₀ GeP ₂ S ₁₂ , Li ₁₀ SnP ₂ S ₁₂ , 70Li ₂ S · 30P ₂ S ₅ or other elements having the same element but different stoichiometric quantities Combinations may be mentioned. In one embodiment of the present disclosure, the organic-inorganic electrolyte formed by blending the electrolyte and the inorganic electrolyte not only has flexibility but also has good conductivity.

  In another embodiment of the present disclosure, a composition for an electrolyte is also provided, comprising a first solution and a second solution. The first solution comprises a reactive additive and a first organic solvent, the reactive additive comprising at least one amide group and at least one epoxy group or vinyl group. The second solution comprises an initiator, a lithium salt and a second organic solvent. With regard to reactive additives, initiators, lithium salts and organic solvents, reference can be made to the description in the preceding related paragraphs herein. In some embodiments, the first organic solvent and the second organic solvent may be the same or different.

  After mixing the first solution and the second solution, the reactive additive in the first solution and the initiator or lithium salt in the second solution initiate a polymerization reaction to form an electrolyte . It should be noted that the first solution and the second solution are stored separately before the first solution and the second solution are mixed to form the electrolyte.

  In some embodiments, the weight percent of the reactive additive in the first solution can be, for example, 5 wt% to 50 wt%, based on the total weight of the first solution and the second solution. By way of example, in some embodiments, the weight percent of the reactive additive may be, for example, 8 wt%, 10 wt%, 20 wt% or 50 wt%, relative to the total weight of the first solution and the second solution.

  In some embodiments, the weight percent of the initiator in the second solution can be, for example, 0.5 wt% to 15 wt%, based on the total weight of the first solution and the second solution.

  In some embodiments, in the mixed solution of the first solution and the second solution, the molar concentration of the lithium salt may be, for example, 0.8 M to 6 M. In some embodiments, the lithium salt in the second solution can be, for example, 5 wt% to 50 wt%, relative to the total weight of the first solution and the second solution.

  In some embodiments, the total weight percent of the first organic solvent and the second organic solvent can be, for example, 40 wt% to 80 wt%, based on the total weight of the first solution and the second solution.

In another embodiment of the present disclosure, a lithium battery is also provided. The lithium battery includes a positive electrode, a negative electrode, and an ion conductive layer disposed between the positive electrode and the negative electrode. The ion conductive layer contains the aforementioned electrolyte. In some embodiments, the material of the positive electrode such as lithium nickel manganese oxide _{(LiNi a Mn 2-a O} 4, 0 <a <2), lithium nickel manganese cobalt oxide (LiNi _n Mn _m Co _{1- nm} O ₂ , 0 <n <1, 0 <m <1, n + m <1), lithium manganate (LiMn ₂ O ₄ ), lithium iron phosphate (LiFePO ₄ ), lithium manganese oxide (LiMnO ₂ ), lithium cobalt oxide (LiCoO _2), lithium nickel cobalt oxide _{(LiNi p Co 1-p O} 2, 0 <p <1) or lithium nickel manganese oxide _{(LiNi q Mn 2-q O} 4, 0 <q <2 And the like. In some embodiments, materials for the negative electrode can include, for example, graphite, lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ), lithium and the like. In one embodiment, the aforementioned lithium battery may further include a separator.

  In the embodiments of the present disclosure, the liquid electrolyte is cured without heating or supplying additional energy by adding a reactive compound having an amide group and an epoxy group or a vinyl group in an appropriate ratio. It can be an electrolyte in a colloidal or quasi-solid state. The colloidal or quasi-solid state electrolytes prepared in the embodiments of the present disclosure not only have flame retardant properties that do not cause liquid leakage, but also between the electrolyte and the battery positive or negative electrode. Interface resistance can be reduced, so that the electrolyte can be used as an ion conducting layer. In addition, batteries using the colloidal or quasi-solid state electrolytes provided by the present disclosure also have excellent rate charging-discharging characteristics and excellent cycle life performance at room temperature.

  The quasi-solid electrolytes and lithium batteries provided by the present disclosure, and various comparative examples and examples are listed below to illustrate their properties.

Comparative Example 1, Examples 1 to 4
Preparation of Electrolyte An organic solvent EC /, such that LiBF ₄ as an initiator and LiPF ₆ as a lithium salt, the concentration of LiBF ₄ in an organic solvent is 0.5 M and the concentration of LiPF ₆ in an organic solvent is 1 M It was dissolved in DMC (v / v = 1: 2). Then, according to the weight and ratio shown in Table 1, to the aforementioned organic solvent containing an initiator which is LiBF ₄ and an initiator which is LiBF ₄ and a lithium salt which is LiPF ₆ according to the weight and ratio shown in Was added. The mixture was mixed at room temperature and stirred thoroughly to form an electrolyte.

  After the aforementioned mixing, the electrolytes prepared in each of the comparative examples and examples were initially in a liquid state. After standing at room temperature for about 12 hours, the morphology of the electrolyte prepared in each of the comparative examples and examples changed. As shown in Table 1, after being reacted at room temperature for about 12 hours, the electrolyte of Example 1 changed to the colloidal state, and the electrolytes of Examples 2 to 4 changed to the quasi-solid state. On the other hand, the electrolyte of Comparative Example 1 still remained in the liquid state.

  From these results, it can be seen that the present disclosure has succeeded in producing electrolytes in a colloidal or quasi-solid state, and that application to a battery system avoids liquid leakage from the battery.

Electrolyte Self-extinguishing Time Test The self-extinguishing time (SET) in each Comparative Example and Example was then tested. According to the reference "J. of Electrochem. Soc. 2002, 149, A6225", it is shown that SET> 20 is a flammable material, and 6 <SET <20 is flame-retardant. It shows that it is a material, and SET <6 shows that it is a flame-resistant material. The test results of each comparative example and example are shown in Table 2.

  As shown in Table 2, as the amount of reactive additive in the electrolyte increases, the self-extinguishing time of the electrolyte is 57 (sec / g) in the comparative example to 0 in Examples 1 to 4 ( It has decreased to sec / g). The colloidal electrolyte prepared in Example 1 and the quasi-solid electrolyte prepared in Examples 2 to 4 are all flame resistant materials.

  The above results show that the electrolyte provided by the present disclosure has good safety because it contains reactive additives.

Electrolyte Conductivity Test of Electrolyte The conductivities of the electrolytes prepared in the respective comparative examples and examples were then tested. The results are shown in Table 3.

As shown in Table 3, conductivity decreases as the amount of reactive additive in the electrolyte increases, but Example 2 (pseudo-solid containing 8 wt% reactive additive) Is similar to that of the ceramic solid electrolyte (about 10 ^-4 S / cm), and there is no drawback of the interfacial resistance that is present in the solid electrolyte. In addition, the ion conductivity of Example 2 is superior to that of general polymer solid electrolytes (for example, PEO, PAN, etc.) (<10 ⁻⁵ S / cm).

Battery Fabrication To assemble the battery, 80 μm thick lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ; LTO) is used as the negative electrode, and 65 μm thick lithium nickel manganese oxide (LiNi _0.5 Mn _1.5 O) ₄ ; LNMO) was used as the positive electrode. The mixed electrolytes of Comparative Example 1 and Example 4 were each injected into the assembled battery. Then, it was allowed to stand at room temperature for about 12 hours, and preparation of the battery was completed.

  After the above reaction at room temperature, a thin film quasi-solid electrolyte layer of only 15 μm thickness was fabricated in a cell using the electrolyte of Example 4 as the electrolyte. As shown in the following experimental results, a thinner electrolyte layer can effectively shorten the ion conduction path, reduce the internal resistance of the battery, and improve the charge and discharge rate characteristics of the battery.

Charge and Discharge Rate Characteristics of Battery A test of the charge and discharge rate of the battery (battery capacity: 250 mAh) manufactured above was performed at room temperature. FIG. 1 shows the results of the charge / discharge rate test of a battery using the liquid electrolyte prepared in Comparative Example 1 as the electrolyte. FIG. 2 shows the results of the charge / discharge rate test of a battery using the pseudo-solid electrolyte prepared in Example 4 as the electrolyte.

  As shown in FIGS. 1 and 2, the charge and discharge rate performance of the two cells is similar, indicating that the electrical performance of the quasi-solid electrolyte is about the same as the liquid electrolyte. However, the safety of the quasi-solid electrolyte is significantly improved. As shown in the results of the self-extinguishing test, the quasi-solid electrolyte prepared in Example 4 has better safety than the liquid electrolyte prepared in Comparative Example 1.

Battery Cycle Life A test of the cycle life of the battery made above was performed at room temperature. FIG. 3 shows the results of cycle life tests of a battery using the liquid electrolyte produced in Comparative Example 1 as the electrolyte and a battery using the quasi-solid electrolyte produced in Example 4 as the electrolyte.

  As shown in FIG. 3, when the pseudo solid electrolyte prepared in Example 4 is used, the capacity retention rate of the battery is better. On the other hand, when the liquid electrolyte produced in Comparative Example 1 is used, the capacity decreases faster, and the final capacity (after 80 cycles) is lower, and the capacity retention rate is deteriorated.

Comparative Example 2, Example 5
Preparation of Organic-Inorganic Pseudo-Solid Electrolyte In Comparative Example 2, Li _1.6 Al _0.6 Ge _1.4 (PO ₄ ) ₃ (LAGP), which is an inorganic ceramic material, was used as a solid electrolyte.

In Example 5, in order to produce an organic-inorganic pseudo-solid electrolyte (LAGP / QSSE), all the components shown in Example 4 in Table 1 and the inorganic electrolyte Li _1.6 Al _0.6 Ge _1.4 (PO ₄ ) ₃ (LAGP) was mixed at a weight ratio of 50/50.

  Conductivity test of organic-inorganic pseudo solid electrolyte

  Tests of the conductivity of the inorganic electrolyte produced in Comparative Example 2 and the organic-inorganic pseudo-solid electrolyte produced in Example 5 were further conducted. The results are shown in Table 4.

As shown in Table 4, the conductivity of the organic-inorganic pseudo-solid electrolyte LAGP / QSSE is close to 10 ^-3 (S / cm) and higher than the inorganic solid ceramic electrolyte of Comparative Example 2. In addition, the morphology confirms that the organic-inorganic pseudo-solid electrolyte LAGP / QSSE prepared using the pseudo-solid electrolyte of Example 4 is flexible.

  The results of the various comparative examples and examples demonstrate that the electrolyte provided by the present disclosure has flame retardancy without causing liquid leakage. Furthermore, the disadvantage of interfacial resistance existing between the electrolyte and the positive electrode or negative electrode can be eliminated. Thus, the electrolyte provided by the present disclosure can be used as an ion conductive layer. In addition, batteries using the electrolyte provided by the present disclosure have excellent charge and discharge rate characteristics and excellent cycle life performance at room temperature. Furthermore, the organic-inorganic pseudo-solid electrolyte prepared by mixing the electrolyte and the inorganic electrolyte provided by the present disclosure also has excellent conductivity and flexibility.

  Although the present disclosure has been described by the several preferred embodiments described above, the present disclosure is not limited to the disclosed embodiments. Those skilled in the art can make changes and variations without departing from the spirit and scope of the present disclosure. Accordingly, the protection scope of the present disclosure should be indicated by the following claims.

Claims (19)

A polymer which is the polymerization product of a reactive additive comprising at least one amide group and at least one epoxy group and an initiator,
Electrolyte containing lithium salt and organic solvent. The electrolyte according to claim 1, wherein the reactive additive has a structure represented by the following formula (I) or contains a structure represented by the following formula (II).

(Wherein, R ¹ and R ² are each independently an unsubstituted or substituted epoxy group, amino group, alkylamino group, alkyl group, alkoxy group, alkenyl group, alkenyloxy group, ether group, ester R ³ represents an unsubstituted or substituted epoxy group, an amino group, an alkylamino group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an ether group or an ester group. , An aryl group, a haloalkyl group, which may contain 1 to 9 repeating units of an amide group, and at least one of R ¹ , R ² , and R ³ is an epoxy, a group containing a group, R ⁴ is a group containing at least one epoxy group, R ⁵ _{is, - (CH 2) n -} , 1 s -CH ₂ - is -NR ⁴ - substituted with - (CH _{2) n} -, or a repeating unit of 1 to 9 in the following amide group

Where n is an integer from 1 to 18. ) The structure represented by the formula (II) is an unsubstituted or substituted cycloalkane which is a 4-membered to 20-membered multi-membered ring, an aromatic hydrocarbon, an aromatic ring, a heterocyclic ring, or 1 Repeat unit of up to 10 amide groups

The electrolyte according to claim 2, which is a structure comprising:   The initiator according to any one of claims 1 to 3, wherein the initiator comprises an ionic compound which can be dissociated to form a nucleophile, a peroxide or azo compound capable of generating free radicals, or a primary amine compound. The electrolyte according to item 1. The ionic compound _{is, CH 3 COOLi, LiOH, LiBF} 4, LiPF 6, LiClO 4, LiTFSI, LiFSI, including LiAsF ₆ or LiSbF _6, electrolyte according to claim 4.   The electrolyte according to claim 4, wherein the peroxide comprises dibenzoyl peroxide (BPO) and the azo compound comprises azobisisobutyronitrile (AIBN). The lithium _{salt, LiBF 4, LiPF 6, LiClO} 4, LiTFSI, LiAsF 6, including LiSbF _6, or a combination thereof, the electrolyte according to any one of claims 1-6.   The electrolyte according to any one of claims 1 to 7, wherein the organic solvent comprises carbonate, sulfonate, nitrile, ether, ester or fluoride.   The electrolyte further includes an inorganic electrolyte, and the inorganic electrolyte includes lithium lanthanum zirconium oxide (lithium zirconium oxide, LLZO), tantalum-doped lithium lanthanum zirconium oxide (tantalum doping lithium lanthanum zirconium oxide, LLZTO), lithium lanthanum titanium oxide (LZTO). lithium lanthanum titanium oxide (LLTO), lithium aluminum titanium phosphate (LATP), aluminum titanium phosphate (germanium aluminum titanium phosphate (LAGP)), lithium germanium phosphorus sulfide (LGPS) or The electrolyte according to any one of claims 1 to 8, wherein lithium tin phosphorous sulfide (LSPS) is included.   The electrolyte according to any one of claims 1 to 9, wherein the weight percentage of the reactive additive is 5 wt% to 50 wt% with respect to the total weight of the electrolyte.   The electrolyte according to any one of claims 1 to 10, wherein the electrolyte is in a colloidal or quasi-solid state. A composition for the electrolyte,
A first solution comprising a reactive additive comprising at least one amide group and at least one epoxy group and a first organic solvent, and a second solution comprising an initiator, a lithium salt and a second organic solvent Including
The composition wherein the first solution and the second solution are stored separately before the first solution and the second solution are mixed to form the electrolyte. The composition according to claim 12, wherein the reactive additive has a structure represented by the following formula (I) or contains a structure represented by the following formula (II).

(Wherein, R ¹ and R ² are each independently an unsubstituted or substituted epoxy group, amino group, alkylamino group, alkyl group, alkoxy group, alkenyl group, alkenyloxy group, ether group, ester R ³ represents an unsubstituted or substituted epoxy group, an amino group, an alkylamino group, an alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, an ether group or an ester group. , An aryl group, a haloalkyl group, which may contain 1 to 9 repeating units of an amide group, and at least one of R ¹ , R ² , and R ³ is an epoxy, And R ⁴ is a group containing at least one epoxy group, and R ⁵ is — (CH ₂ ) _n —, one or more of —CH ₂ - is -NR ⁴ - substituted with - (CH _{2) n} -, or a repeating unit of 1 to 9 in the following amide group

Where n is an integer from 1 to 18. ) The structure represented by the formula (II) is an unsubstituted or substituted cycloalkane which is a 4-membered to 20-membered multi-membered ring, an aromatic hydrocarbon, an aromatic ring, a heterocyclic ring, or 1 Repeat unit of up to 10 amide groups

The composition according to claim 13, which is a structure comprising   The composition according to any one of claims 12 to 14, wherein the weight percentage of the reactive additive is 5 wt% to 50 wt% with respect to the total weight of the first solution and the second solution. Positive electrode,
An ion conductive layer comprising the negative electrode, and the electrolyte according to any one of claims 1 to 11 disposed between the positive electrode and the negative electrode,
Containing lithium batteries. The material of the positive electrode, lithium nickel-manganese oxide _{(LiNi a Mn 2-a O} 4, 0 <a <2), lithium nickel manganese cobalt oxide _{(LiNi n Mn m Co 1-} nm O 2, 0 <n < 1, 0 <m <1, n + m <1), lithium manganate (LiMn ₂ O ₄ ), lithium iron phosphate (LiFePO ₄ ), lithium manganese oxide (LiMnO ₂ ), lithium cobalt oxide (LiCoO ₂ ), lithium nickel cobalt oxide _{(LiNi p Co 1-p O} 2, 0 <p <1) or lithium nickel manganese oxide _{(LiNi q Mn 2-q O} 4, 0 <q <2) including, in claim 16 Description Lithium battery. The lithium battery according to claim 16, wherein the material of the negative electrode contains graphite, lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ) or lithium.   The lithium battery according to any one of claims 16 to 18, further comprising a separator.

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