KR20080007167A - Electrolyte with catechol carbonate substituted by eleectron withdrawing group and secondary battery comprising the same - Google Patents

Abstract

An electrolyte for a secondary battery is provided to form a more dense and firm solid electrolyte interface layer on the surface of an anode by virtue of a decreased reduction potential, thereby improving the lifespan and stability of a battery. An electrolyte for a secondary battery comprises an electrolyte salt and a solvent, and further comprises catechol carbonate substituted with an electron-withdrawing group. The catechol carbonate substituted with an electron-withdrawing group is a compound represented by the following formula 1, wherein at least one of R1-R4 is an electron-withdrawing group and the other substituents each independently represent H, a C1-C20 alkyl or phenyl.

Description

ELECTROLYTE WITH CATECHOL CARBONATE SUBSTITUTED BY ELEECTRON WITH DRAWING GROUP AND SECONDARY BATTERY COMPRISING THE SAME}

The present invention is a non-aqueous electrolyte; And it relates to a secondary battery comprising the same. More specifically, the present invention is a non-aqueous electrolyte containing a compound capable of improving the life performance and safety of the secondary battery; And it relates to a secondary battery comprising the same.

In recent years, with the trend of miniaturization and weight reduction of electronic devices, miniaturization and weight reduction of batteries acting as power sources are also required. BACKGROUND ART Secondary batteries have been put to practical use as small-sized, light-weight, high-capacitance rechargeable batteries, and are used in portable electronic and communication devices such as small video cameras, mobile phones, and notebook computers.

The secondary battery may be composed of a positive electrode, a negative electrode, a porous separator, and a non-aqueous electrolyte containing an electrolyte salt and an electrolyte solvent.

The non-aqueous electrolyte generally requires the following characteristics with respect to the operation and use of the battery. First, it must be able to sufficiently transfer ions between two electrodes during insertion and desorption of lithium ions from the cathode and anode, and second, it is electrochemically stable at the potential difference between the two electrodes, so that there is little concern about side reactions such as decomposition of electrolyte components. .

However, common electrolyte solvents, such as carbonate organic solvents, may decompose on the surface of the electrode during charge and discharge, causing side reactions in the battery. Particularly, molecular weights such as ethylene carbonate (EC), dimethyl carbonate (DMC), or diethyl carbonate (DEC) may be used. This large organic solvent can be co-intercalated between the graphite layers in the carbon-based negative electrode, disrupting the structure of the negative electrode.

On the other hand, it is known that the problem can be solved by a solid electrolyte interface (SEI) film formed on the surface of the negative electrode by electrical reduction of the carbonate-based organic solvent during the initial charging of the battery. However, when the SEI film is formed, lithium ions in the electrolyte are irreversibly involved, resulting in a decrease in battery capacity. In addition, the SEI film is generally not electrochemically stable and can easily collapse. Therefore, the battery capacity is reduced due to the continuous regeneration of the SEI film during charging and discharging of the battery, which may lower the lifespan performance of the battery.

In addition, side reactions such as decomposition of the electrolyte may occur on the exposed surface of the negative electrode due to the collapse of the SEI film, and a problem may occur that the battery swells or the internal pressure increases due to the generated gas.

In order to solve the above problems, 1,3-propanesultone (Japanese Patent Application No. 1999-339850), 1,3-propenesultone (1,3-propensultone; Japanese Patent Application No. 2001- 151863) has been presented. However, even in the case of the above method, the capacity is gradually decreased as the cycle is continued, and there are still problems as described above.

The present invention uses a catechol carbonate in which the electron withdrawing group (EWG) is substituted as a component of the electrolyte and the self-reduction potential is reduced, thereby forming a denser and more robust SEI film on the surface of the cathode. To improve the lifespan performance and stability of the battery.

The present invention provides a secondary battery electrolyte comprising an electrolyte salt and an electrolyte solvent, the electrolyte comprising an catechol carbonate substituted with an electron withdrawing group (EWG); And it provides a secondary battery having the electrolyte solution.

In addition, the present invention is an electrode formed on a part or all of the surface of the electrode active material SEI film containing a reducing agent of catechol carbonate substituted with an electron withdrawing group (EWG); And it provides a secondary battery having the electrode.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention is characterized by using a catechol carbonate having a reduced self-reduction potential by replacing the electron withdrawing group (EWG) as a component of the electrolyte, thereby improving the lifespan and stability of the secondary battery. Such battery performance improving effect can be estimated as follows, but is not limited thereto.

Since the catechol carbonate of the present invention has a reduced self-reduction potential due to substitution of an electron withdrawing group (EWG), the catechol carbonate may be reduced at a lower potential than a general electrolyte solvent, such as a carbonate-based organic solvent. Therefore, not only can the SEI film be formed before the electrolyte solvent at the time of initial charging of the battery, but also the SEI film can be regenerated before the electrolyte solvent even when the SEI film is collapsed by repeated charge and discharge. As a result, in the present invention, the amount of irreversible lithium ions consumed to form the SEI film can be reduced, and the decrease in battery initial capacity and charge / discharge capacity can be minimized. In addition, since the SEI film is more robust and dense and has excellent stability, side reactions between lithium ions and electrodes in the electrolyte and deterioration of the negative electrode can be more effectively suppressed.

On the other hand, the SEI film generally acts as a resistance film to the movement of lithium ions to the negative electrode active material may interfere with the smooth movement of lithium, the SEI film formed on the surface of the cathode according to the present invention is an electron-off group (EWG) It can be easily polarized, including, it is possible to facilitate the smooth movement of lithium ions to the negative electrode active material. As a result, in the present invention, the amount of irreversible lithium ions consumed by charging and discharging of the battery can be reduced, and battery capacity reduction can be minimized.

The electron withdrawing group (EWG) introduced in the present invention may be substituted with one or more phenylene groups of catechol carbonate. In addition, the electronic attracting group (EWG) is not particularly limited as long as it can only serve as electron withdrawing with electron affinity as known in the art.

Non-limiting examples of the electron withdrawing group of the electron withdrawing group (EWG) are halogen atom (F, Cl, Br, I), cyano (CN) group, nitro (NO ₂ ) group, trifluoromethane (CF ₃ ) Group, pentafluoroethane (C ₂ F ₅ ) group, trifluoro methane sulfonyl (SO ₂ CF ₃ ) group, pentafluoroethane sulfonyl (SO ₂ C ₂ F ₅ ) group, trifluoro methane sulfonate (SO ₃ CF ₃ ) group, pentafluoro ethane sulfonate (SO ₃ C ₂ F ₅ ) group, pentafluoro phenyl (C ₆ F ₅ ) group, alcetyl group (COCH ₃ ) group, ethyl ketone (COC ₂ H ₅ ) group , Propyl ketone (COC ₃ H ₇ ) group, butyl ketone (COC ₄ H ₉ ) group, pentyl ketone (COC ₅ H ₁₁ ) group, hexyl ketone (COC ₆ H ₁₃ ) group, ethane oate (CO ₂ CH ₃ ) Group, propanoate (CO ₂ C ₂ H ₅ ) group, butane oate (CO ₂ C ₃ H ₇ ) group, pentanoate (CO ₂ C ₄ H ₉ ) group, hexane oate (CO ₂ C ₅ H ₁₁ ) and the like, with halogen being preferred.

The catechol carbonate substituted with the electron withdrawing group (EWG) of the present invention may be a compound represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, at least one of R1 to R4 is an electron withdrawing group (EWG), and other substituents are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, or a phenyl group.

Non-limiting examples of the catechol carbonate include 3-fluorocatechol carbonate, 4-fluorocatechol carbonate, 3,5-difluorocatechol carbonate (3-difluorocatechol carbonate), 3,4,5,6-tetrafluorocatechol carbonate (3,4,5,6-tetrafluorocatechol carbonate), 3-fluoro-6-methylcatechol carbonate (3-fluoro- 6-methylcatechol carbonate) and 3,5-difluoro-4-methylcatechol carbonate.

In the secondary battery electrolyte provided in the present invention, the content of the catechol carbonate substituted with the electron withdrawing group (EWG) can be adjusted according to the goal of improving the performance of the battery, but 0.1 to 30 parts by weight per 100 parts by weight of the electrolyte desirable. When using less than 0.1 parts by weight, the desired life-improving effect is insignificant, and when it exceeds 30 parts by weight, the viscosity of the electrolyte may increase, thereby lowering the lithium ion transfer ability. In addition, the content of the catechol carbonate may be more preferably 0.5 to 10 parts by weight per 100 parts by weight of the electrolyte. If it is out of the above range, the initial capacity of the battery may be reduced by increasing the amount of lithium ions consumed to form the SEI film during initial charging.

In addition to the catechol carbonate, the secondary battery electrolyte of the present invention may include conventional electrolyte components known in the art, such as electrolyte salts and electrolyte solvents.

The electrolyte salt is A ⁺ B ^- A salt of the structure, such as, A ⁺ is Li ^+, Na ^+, K ⁺ comprises an alkaline metal cation or an ion composed of a combination thereof, such as, and B ^- is PF ₆ ^-, BF ₄ ^{-, Cl -, Br -,} I -, ClO 4 -, AsF 6 -, CH 3 CO 2 -, CF 3 SO 3 -, N (CF 3 SO 2) 2 -, C (CF 2 SO 2) 3 - It is a salt containing an ion such as anion or a combination thereof. In particular, lithium salts such as LiClO ₄ , LiCF ₃ SO ₃ , LiPF ₆ , LiBF ₄ , LiN (C ₂ F ₅ SO ₂ ) ₂ , or Li (CF ₃ SO ₂ ) ₂ are preferred.

In addition, the electrolyte solvent may be used conventional organic solvents known in the art, such as cyclic carbonate and / or linear carbonate. In particular, in order to increase the dissociation and transfer ability of lithium ions of the electrolyte, it is preferable to use a cyclic carbonate having a high polarity, and to mix the cyclic carbonate and linear carbonate in order to prevent a decrease in the lithium ion conductivity due to the viscosity increase of the electrolyte. It is more preferable to improve the lifespan characteristics of the battery. Non-limiting examples of the solvent solvent is propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxy Ethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethylmethyl carbonate (EMC), gamma butyrolactone (GBL), fluoroethylene carbonate (FEC), methyl formate, ethyl formate , Propyl formate, methyl acetate, ethyl acetate, propyl acetate, pentyl acetate, methyl propionate, ethyl propionate, ethyl propionate, butyl propionate or mixtures thereof. Moreover, the halogen derivative of the said organic solvent can also be used.

The present invention also provides an electrode, preferably a negative electrode, in which an SEI film containing a reduced substance of catechol carbonate substituted with an electron withdrawing group (EWG) is formed on part or all of the surface of the electrode active material. The electrode is assembled according to a battery cell using an electrode prepared according to a conventional method known in the art and an electrolyte solution containing a catechol carbonate substituted with an electron withdrawing group (EWG), and then charged and discharged at least once It can be prepared by forming an SEI film on the surface of the active material. In addition, before assembling the battery unit, an electrode in which the SEI film is preformed may be manufactured by electrically reducing the electrolyte containing the compound in the state of being impregnated with an electrode prepared according to a conventional method known in the art.

The electrode before the SEI film is formed can be prepared according to a conventional method known in the art, for example, a slurry by mixing and stirring a solvent, a binder, a conductive material, a dispersant as necessary in the electrode active material. After the preparation, it may be prepared by coating (coating), compressing and drying the current collector of a metal material.

As the negative electrode active material, a conventional negative electrode active material that can be used for a negative electrode of a conventional secondary battery can be used. Non-limiting examples thereof include lithium adsorbents such as lithium metal or lithium alloy carbon, petroleum coke, activated carbon, graphite, graphite, graphitized carbon or other carbons. It is preferable to use graphitized carbon having a crystal surface distance constant d002 of a carbonaceous material measured by X-ray diffraction method up to 0.338 nm and a specific surface area measured by BET method up to 10 m ² / g. Non-limiting examples of cathode current collectors include foils made of copper, gold, nickel or copper alloys or combinations thereof.

Furthermore, the secondary battery of the present invention is a solid electrolyte interface (SEI) film containing an electrolyte containing a catechol carbonate substituted with an electron withdrawing group (EWG), and / or a reducing compound of the compound, or part or all of the surface of the electrode active material It includes an electrode formed on. Preferably, the present invention is a separator, a positive electrode, a negative electrode formed on a part or all of the surface of the electrode active material is a solid electrolyte interface (SEI) film containing a reducing agent of catechol carbonate substituted with an electron withdrawing group (EWG); And / or provides a secondary battery having an electrolyte solution containing the compound.

Non-limiting examples of the secondary battery includes a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery or a lithium ion polymer secondary battery.

The positive electrode to be applied to the secondary battery of the present invention is not particularly limited, and according to a conventional method known in the art, the positive electrode active material may be prepared in a form bound to the positive electrode current collector. The positive electrode active material may be a conventional positive electrode active material that can be used for the positive electrode of a conventional secondary battery, non-limiting examples of lithium such as LiM _x O _y (M = Co, Ni, Mn, Co _a Ni _b Mn _c ) Transition metal composite oxides (for example, lithium manganese composite oxides such as LiMn ₂ O ₄ , lithium nickel oxides such as LiNiO ₂ , lithium cobalt oxides such as LiCoO ₂ , and some of the manganese, nickel and cobalt oxides of these oxides And the like, or a vanadium oxide containing lithium) or a chalcogen compound (for example, manganese dioxide, titanium disulfide, molybdenum disulfide, and the like). Preferably LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , LiMn ₂ O ₄ , Li (Ni _a Co _b Mn _c ) O ₂ (0 <a <1, 0 <b <1, 0 <c <1, a + b + c = 1), LiNi _1-Y Co _Y O ₂ , LiCo _1-Y Mn _Y O ₂ , LiNi _1-Y Mn _Y O ₂ (where 0 ≦ Y <1), Li (Ni _a Co _b Mn _c ) O ₄ (0 <a <2, 0 <b <2, 0 <c <2, a + b + c = 2), LiMn _2-z Ni _z O ₄ , LiMn _2-z Co _z O ₄ ( Here, 0 <Z <2), LiCoPO ₄ , LiFePO _4, or a mixture thereof is mentioned. Non-limiting examples of the positive electrode current collector include a foil made of aluminum, nickel, or a combination thereof.

The separator is not particularly limited, but a porous separator may be used, for example, a polypropylene-based, polyethylene-based, or polyolefin-based porous separator.

The secondary battery according to the present invention may be manufactured according to a conventional method known in the art, for example, an electrolyte prepared according to the present invention after assembling a separator between an anode and a cathode. It can be prepared by injecting.

The appearance of the secondary battery according to the present invention is not limited, but can be cylindrical, coin-shaped, square or pouch (pouch) of the can.

The electrolyte solution for secondary batteries of the present invention can improve the life and stability of the secondary battery by forming a more robust and dense SEI film on the negative electrode surface.

Various modifications may be made without departing from the spirit and scope of the invention as set forth in the claims.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the following examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example  One

Example 1-1

An electrolyte solution was prepared by adding 2 parts by weight of 3-fluorocatechol carbonate to a 1M LiPF ₆ solution of ethylene carbonate and ethylmethyl carbonate in a volume ratio of 1: 2.

Example 1-2

The negative electrode was mixed with 93 parts by weight of graphitized carbon and 7 parts by weight of polyvinylidene difluoride (PVDF) as a solvent, N-methyl-2-pyrrolidone, and mixed in a mixer for 2 hours. It was prepared by coating a copper foil current collector and drying at 130 ° C. A positive electrode was prepared by mixing 91 parts by weight of LiCoO ₂ , 3 parts by weight of PVDF and 6 parts by weight of conductive carbon, and N-methyl-2-pyrrolidone in a mixer, followed by coating on an aluminum foil current collector and drying at 130 ° C. . The anode was cut in a circular shape, placed in a coin-shaped can, and a separator (celgard 2400) was placed, and a cathode cut in a circular shape was placed. After sufficiently impregnated with the electrolyte solution prepared in Example 1-1, a coin-type battery was manufactured by covering and pressing a coin-type cap.

Example 2

An electrolyte solution was prepared in the same manner as in Example 1 except that 0.5 parts by weight of 3-fluorocatechol carbonate was added instead of 2 parts by weight; And a secondary battery.

Example 3

An electrolyte solution was prepared in the same manner as in Example 1, except that 10 parts by weight of 3-fluorocatechol carbonate was added instead of 2 parts by weight of electrolyte. And a secondary battery.

Example  4

An electrolyte solution was prepared in the same manner as in Example 1, except that 4-fluorocatechol carbonate was added instead of 3-fluorocatechol carbonate to prepare an electrolyte solution. And a secondary battery.

Example 5

Example 1 Except that an electrolyte was prepared using an ethylene carbonate, propylene carbonate, diethyl carbonate 1: 1: 2 volumetric 1M LiPF ₆ solution instead of an ethylene carbonate and ethylmethyl carbonate 1: 2 volumetric 1M LiPF ₆ solution. Electrolyte solution in the same manner as 1; And a secondary battery.

Comparative Example 1

Electrolyte solution in the same manner as in Example 1, except that no compound was added to the 1 M LiPF ₆ solution of ethylene carbonate and ethylmethyl carbonate in a volume ratio of 1: 2; And a secondary battery.

Comparative Example 2

2 parts by weight of catechol carbonate (catechol carbonate) was added to a 1M LiPF ₆ solution of ethylene carbonate and ethylmethyl carbonate in a volume ratio of 1: 2; And a secondary battery.

Experimental Example 1. Performance Evaluation of Secondary Batteries

The secondary batteries prepared in Examples and Comparative Examples were charged at 25 ° C. to 4.2 V at a rate of 0.5 C, charged at 4.2 V until the current became 0.05 mA or less, and discharged at a rate of 0.5 C to 3 V. Charge and discharge experiments were conducted. The discharge capacity retention rate (%) was expressed as a percentage of the ratio of the discharge capacity to the initial discharge capacity after 50 cycles. The results are shown in Table 1.

TABLE 1

Electrolyte additive Addition amount (part by weight) Electrolyte Composition (Volume Ratio) Initial discharge capacity (mAh) Discharge Capacity Retention Rate (%) Example 1 3-fluorocatechol carbonate 2.0 1M LiPF ₆ EC / EMC = 1/2 4.37 92.4 Example 2 3-fluorocatechol carbonate 0.5 1M LiPF ₆ EC / EMC = 1/2 4.19 88.6 Example 3 3-fluorocatechol carbonate 10.0 1M LiPF ₆ EC / EMC = 1/2 4.11 89.5 Example 4 4-fluorocatechol carbonate 2.0 1M LiPF ₆ EC / EMC = 1/2 4.45 91.8 Example 5 3-fluorocatechol carbonate 2.0 1M LiPF ₆ EC / PC / DEC = 1/1/2 4.34 92.2 Comparative Example 1 - - 1M LiPF ₆ EC / EMC = 1/2 4.23 84.6 Comparative Example 2 Catechol carbonate 2.0 1M LiPF ₆ EC / EMC = 1/2 4.33 88.7

As a result of the experiment, the battery of Examples 1 to 5 using the electrolyte solution containing the catechol carbonate substituted with the electron withdrawing group (EWG) according to the present invention, the battery of Comparative Example 1 using the electrolyte solution without adding any compound, and Compared with the battery of Comparative Example 2 using an electrolyte containing catechol carbonate, excellent discharge capacity retention rate was shown. In addition, the batteries of Examples 1, 4 and 5 according to the present invention showed a higher initial capacity than the batteries of Comparative Examples 1 and 2.

From this, when using the catechol carbonate substituted by the electron-withdrawing group in the present invention as an electrolyte component, not only can improve the battery life performance, but also minimize the amount of irreversible lithium ions consumed when the SEI film is generated. And it was found.

Experimental Example 2

Charge the secondary batteries prepared in Example 1 and Comparative Examples 1 and 2 at a rate of 0.5C to 4.2V at 25 ℃, and charging at 4.2V until the current is 0.05mA or less and the speed of 0.5C to 3V After charging and discharging three times to discharge the battery, the battery was disassembled in a discharged state to collect a negative electrode. Differential scanning calorimetry (DSC) analysis was performed on the cathode, and the measured exothermic peak temperature was shown in FIG. 1. At this time, the exothermic peak temperature is generally assumed to be due to the thermal collapse of the SEI film formed on the surface of the cathode.

As a result, the exothermic reaction pattern of the negative electrode was different from each other depending on the electrolyte solution used in Example 1 and Comparative Examples 1 and 2. From this, it was found that the catechol carbonate substituted with the electron withdrawing group (EWG) used in the electrolytic solution of the present invention was involved in the formation of the SEI film on the surface of the negative electrode.

In addition, the battery of Example 1 using the electrolyte solution containing catechol carbonate substituted with the electron withdrawing group (EWG) according to the present invention, the battery of Comparative Example 1 using the electrolyte solution without adding any compound, and catechol carbonate The exothermic peak temperature was higher than that of the battery of Comparative Example 2 using the containing electrolyte (see FIG. 1). In general, the higher the exothermic peak temperature in the DSC analysis, the better the thermal stability of the SEI film formed on the surface of the cathode. From this, it can be seen that the SEI film formed by the catechol carbonate in which the electron withdrawing group (EWG) is substituted according to the present invention has better thermal stability.

1 is a graph of differential scanning calorimetry (DSC) analysis according to Experimental Example 2. FIG.

Claims (9)

A secondary battery electrolyte comprising an electrolyte salt and an electrolyte solvent, wherein the electrolyte includes a catechol carbonate substituted with an electron withdrawing group (EWG). The electrolyte solution for a secondary battery according to claim 1, wherein the catechol carbonate substituted with the electron withdrawing group is a compound represented by the following Chemical Formula 1. [Formula 1]

In Formula 1, at least one of R1 to R4 is an electron withdrawing group (EWG), and other substituents are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, or a phenyl group. The method of claim 1, wherein the electron withdrawing group is halogen, cyano group, nitro group, trifluoromethane group, pentafluoroethane group, trifluoro methane sulfonyl group, pentafluoro ethane sulfonyl group, trifluoro methane sulfonate group, pentafur Orethane sulfonate group, pentafluoro phenyl group, alcetyl group, ethyl ketone group, propyl ketone group, butyl ketone group, pentyl ketone group, hexyl ketone group, ethanoate group, propaneoate group, butanoate group, pentaneoate Electrolyte solution for a secondary battery, characterized in that selected from the group consisting of a group, and a hexane oate group. The electrolyte of claim 1, wherein the content of the catechol carbonate substituted with the electron withdrawing group is 0.1 to 30 parts by weight per 100 parts by weight of the electrolyte. The electrolyte of claim 1, wherein the content of the catechol carbonate substituted with the electron withdrawing group (EWG) is 0.5 to 10 parts by weight per 100 parts by weight of the electrolyte. An electrode in which a solid electrolyte interface membrane containing a reduced substance of catechol carbonate in which an electron withdrawing group is substituted is formed on part or all of the surface of an electrode active material. The electrode according to claim 6, wherein the catechol carbonate substituted with the electron withdrawing group is a compound represented by the following Chemical Formula 1. [Formula 1]

In Formula 1, at least one of R1 to R4 is an electron withdrawing group (EWG), and other substituents are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, or a phenyl group. The method of claim 6, wherein the electron withdrawing group (EWG) is halogen, cyano group, nitro group, trifluoromethane group, pentafluoroethane group, trifluoro methane sulfonyl group, pentafluoro ethane sulfonyl group, trifluoro methane sulfonate Group, pentafluoro ethane sulfonate group, pentafluoro phenyl group, alcetyl group, ethyl ketone group, propyl ketone group, butyl ketone group, pentyl ketone group, hexyl ketone group, ethane oate group, propanoate group, butaneoate group Electrode, characterized in that selected from the group consisting of, pentane-oate group, and hexane-oate group. In a secondary battery comprising a positive electrode, a negative electrode and an electrolyte, the secondary battery The electrolyte solution is an electrolyte solution for a secondary battery according to any one of claims 1 to 5; The positive electrode or the negative electrode is an electrode according to any one of claims 6 to 8; Or a secondary battery comprising both the electrolyte and the electrode.

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