KR101633070B1 - Composite electrode material of lithium secondary battery and lithium secondary battery - Google Patents

Abstract

A composite cathode material of a lithium secondary battery and a lithium secondary battery are provided. The composite cathode material of the lithium secondary battery includes at least an electrode active powder and a nanoscale coating layer coated on the electrode active powder, and the nanoscale coating layer is composed of a metastable polymer, a compound A, a compound B, or a combination thereof. The compound A is a monomer having a reactive end functional group, and the compound B is a heterocyclic amino aromatic derivative used as an initiator. The weight ratio of the nanoscale coating layer to the composite electrode material of the lithium secondary battery is 0.005% to 10%.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite electrode material of a lithium secondary battery,

The present disclosure relates to a composite electrode material of a lithium secondary battery and a lithium secondary battery.

Lithium secondary batteries have become a battery system that has gained much attention in recent years due to their high energy density, high operating voltage, low self-discharge rate, and long shelf life. The lithium secondary battery is widely used in portable electronic applications such as mobile phones, tablet PCs, and digital cameras. The initial lithium battery includes a lithium metal as an anode, an intercalation compound (e.g., Li _x CoO ₂ and Li _x MnO ₂ ) composed of a transition metal oxide as a cathode, and lithium ions as an electrolyte Was used as the nonaqueous organic electrolyte solution. After the battery is discharged a plurality of times, a dendritic crystal is easily formed on the negative electrode of the battery, so that the separator used for separating the positive electrode and the negative electrode material can easily penetrate, Lt; / RTI > In addition, the battery is rapidly heated, causing a decomposition reaction of the electrolyte and the cathode material, which in turn can cause hazards such as ignition and explosion.

Therefore, the surface of the electrode of the lithium secondary battery needs to have a protective layer in order to prevent direct contact with the electrolyte and to suppress delithiation of the electrode and side reaction of the electrolyte. In the prior art, the category of the protective layer of the anode surface is a metal (e.g., Ag), a metal oxide (e.g. Al ₂ O ₃ And a ZrO _2), metal fluorides (e.g., AlF ₃ and ZrF _2), and a plurality of carbon composite material (for example, graphene). In all of the above categories, an organic material is coated on the surface of the anode. Moreover, the process of making the coating is complex and expensive. The preferable protective layer on the electrode surface of the lithium secondary battery not only promotes the electrochemical characteristics and the thermal stability, but also needs to improve the cycle life of the battery at a high temperature. In addition, the manufacturing process needs to be simplified in order to reduce the cost.

The present disclosure provides a composite electrode material for a lithium secondary battery.

The present disclosure also provides a lithium secondary battery.

The present disclosure provides a composite electrode material for a lithium secondary battery. Wherein the composite electrode material comprises an electrode active powder and a nanoscale coating layer coated on the surface of the electrode active powder, wherein the nanoscale coating layer comprises a metastable state polymer, a compound A, a compound B, . The compound A is a monomer having a reactive end functional group, and the compound B is a heterocyclic amino aromatic derivative used as an initiator. The weight ratio of the nanoscale coating layer to the composite electrode material of the lithium secondary battery is 0.005% to 10%.

The present disclosure also provides a composite electrode material for a lithium secondary battery. Wherein the composite nanoparticle coating layer comprises a first metastable polymer, a compound A, a compound B, a second nanostructured polymer, and a second nanostructured coating layer, , Or a combination thereof. The compound A is a monomer having a reactive end functional group, and the compound B is a heterocyclic amino aromatic derivative used as an initiator. The weight ratio of the first nanoscale coating layer to the composite electrode material of the lithium secondary battery is 0.005% to 10%.

The present disclosure also provides a lithium secondary battery. The lithium secondary battery includes at least one electrode material, a non-aqueous electrolyte, and a separator. The electrode material is a composite electrode material of the lithium secondary battery described above. The nonaqueous electrolyte solution is in contact with the electrode material, and the nonaqueous electrolyte solution includes a nonaqueous solvent and a lithium salt. The separator is placed in the non-aqueous electrolyte.

Some exemplary implementations accompanying the figures are additionally described in detail below in order to describe the present disclosure in detail.

The accompanying drawings are included to provide further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary implementations and, together with the description, serve to explain the principles of the disclosure.
1 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a first exemplary embodiment of the present disclosure.
2 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a second exemplary embodiment of the present disclosure.
3 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a third exemplary embodiment of the present disclosure.
4 is a schematic view of a lithium secondary battery according to a fourth exemplary embodiment of the present disclosure;
FIG. 5 is a transmission electron microscope (TEM) photograph of the composite cathode material of the lithium secondary battery manufactured in Example 1. FIG.
6 shows a curve diagram of a charge-discharge cycle test result of the first embodiment.
FIG. 7 shows a curve diagram of the results of the charge-discharge cycle test of Example 2. FIG.
FIG. 8 shows a curve diagram of the charge-discharge cycle test result of Example 3. FIG.
FIG. 9 shows a curve diagram of the charge-discharge cycle test result of Example 4. FIG.
10A is a scanning electron microscope (SEM) photograph of an initial composite cathode material of a lithium secondary battery manufactured in Example 4. FIG.
10B is a SEM photograph of the composite cathode material of the lithium secondary battery manufactured in Example 4 after multiple cycles.
10C is a SEM photograph of the composite anode material of the lithium secondary battery manufactured in Example 4 after multiple cycles.
11A is a SEM photograph of the initial uncoated cathode material prepared in Example 4. Fig.
11B is a SEM photograph of the uncoated cathode material prepared in Example 4 after multiple cycles.
11C is a SEM photograph of the uncoated cathode material prepared in Example 4 after multiple cycles.
12 is a curve diagram of the charge-discharge cycle test result of the fifth embodiment.
13 is a TEM photograph of the composite cathode material of the lithium secondary battery manufactured in Example 6. Fig.
FIG. 14 is a curve diagram of a charge-discharge cycle test result of Example 7. FIG.
15 is a curve diagram of the decomposition potential of the electrolytic solution of Example 8. Fig.
16 is a curve diagram of the decomposition potential of the electrolytic solution of Comparative Example 7 and Example 9, respectively.
17 is gel permeation chromatography (GPC) of the metastable polymer of Example 1.
18 is a GPC diagram of the metastable polymer of Example 5;
19 is a GPC diagram of the metastable polymer of Example 7.

1 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a first exemplary embodiment of the present disclosure.

Referring to FIG. 1, a composite electrode material 10 of a lithium secondary battery includes an electrode active powder 100 and a nanoscale coating layer 102 coated on a surface 100a of the electrode active powder 100. In particular, the nanoscale coating layer 102 is formed from a metastable polymer, Compound A, Compound B, or a combination thereof. Specifically, the compound A is a monomer having a reactive end functional group, and the compound B is a heterocyclic amino aromatic derivative used as an initiator. The weight ratio of the nanoscale coating layer 102 to the composite electrode material 10 of the lithium secondary battery is 0.005% to 10%. Although FIG. 1 shows only one grain of the electrode active powder 100, it should be clear to those skilled in the art that the electrode material of the lithium secondary battery is usually made of a plurality of powder particles. In this embodiment, the electrode active powder 100 may be a cathode material or a cathode material having a thickness of 1 nm to 30 nm. When the electrode active powder 100 is used as a cathode material, the electrode active powder 100 may be a lithium-containing oxide, a lithiated sulphide, a lithiated selenide, a lithiated telluride of vanadium, , Titanium, chromium, copper, molybdenum, niobium, iron, nickel, cobalt, manganese, and combinations thereof. Specifically, the electrode active powder 100 may be LiMn ₂ O ₄ , LiNi _x Co _y O ₂ , LiCoO ₂ , LiFePO ₄ , LiNi _x Co _y Mn _z O ₂ , or LiNi _x Mn _y O ₂ . When the anode is discharging, lithium ions are inserted into the cathode material. When the anode is being charged, lithium ions are extracted. When the electrode active powder 100 is used as a negative electrode material, the electrode active powder 100 may be selected from the group consisting of mesocarbon microbeads (MCMB), mesophase graphite powder (MGP), vapor grown carbon fibers (VGCF), carbon nanotubes ), Coke, carbon black, natural graphite, artificial graphite, acetylene black, carbon fiber, vitreous carbon, lithium alloy, and combinations thereof. The negative electrode selected from the metal group may be, for example, Al, Zn, Bi, Cd, Sb, Si, Pb, Sn, Li ₃ FeN ₂ , Li _{2 .6} Co _{0 .4} N, Li _{2 .6} Cu _{0 . 4} N, or a combination of these. Additionally, the negative electrode plate for a metal oxide, such as _{SnO, SnO 2, GeO, GeO} 2, In 2 O, In 2 O 3, PbO, PbO 2, Pb 2 O 3, Pb 3 O 4, AgO, Ag 2 O, Ag ₂ O ₃ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , SiO, ZnO, CoO, NiO, FeO, TiO ₂ , Li ₃ Ti ₅ O ₁₂ , When the negative electrode is being charged, lithium ions are intercalated into the negative electrode material. When the cathode is discharging, lithium ions are de-intercalated. The compound A, compound B, metastable state polymer, or combinations thereof used to form the nanoscale coating layer 102 are described in detail below.

2 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a second exemplary embodiment of the present disclosure.

2, the composite electrode material 20 of the lithium secondary battery includes an electrode plate 202 composed of an electrode active powder 200 and a nanoscale coating layer (not shown) coated on the surface 202a of the electrode plate 202 204, and the nanoscale coating layer 204 is formed from a metastable polymer, Compound A, Compound B, or a combination thereof. The compound A is a monomer having a reactive end functional group, and the compound B is a heterocyclic amino aromatic derivative used as an initiator. In addition, the weight ratio of the nanoscale coating layer 204 to the composite electrode material 20 of the lithium secondary battery is 0.005% to 10%. The thickness of the nanoscale coating layer 204 is, for example, 1 nm to 30 nm. The electrode active powder 200 used in this embodiment is discussed in the first embodiment above and is not repeated here. The compound A, compound B, metastable polymer, and preparation thereof used to form the nanoscale coating layer 204 are described in detail below.

3 is a schematic cross-sectional view of a composite electrode material of a lithium secondary battery according to a third exemplary embodiment of the present disclosure.

3, a composite electrode material 30 of a lithium secondary battery includes an electrode plate 302 composed of an electrode active powder 300 and a first nanoscale electrode 300 coated on a surface 302a of the electrode plate 302. [ Coating layer 304a. And the second nanoscale coating layer 304b is coated on the surface 300a of the electrode active powder 300. [ In particular, the first nanoscale coating layer 304a is formed from a first metastable polymer, Compound A, Compound B, or a combination thereof. The weight ratio of the first nanoscale coating layer 304a to the composite electrode material 30 of the lithium secondary battery is, for example, 0.005% to 10%. The second nanoscale coating layer 304b is formed from a second metastable polymer, Compound A, Compound B, or a combination thereof. The weight ratio of the second nanoscale coating layer 304b to the composite electrode material 30 of the lithium secondary battery is, for example, 0.005% to 10%. The electrode active powder 300 used in this embodiment is discussed in the first embodiment and is not repeated here. The thickness of the second nanoscale coating layer 304b is, for example, 1 nm to 30 nm. The compound A, compound B, first and second metastable polymers are described in detail below.

In the first, second, and third exemplary embodiments, the metastable state polymer, the first metastable state polymer, and the second metastable state polymer are each independently generated from the reaction of compound A and compound B , The molar ratio of compound A to compound B is 10: 1 to 1:10.

In addition, the metastable polymers mentioned in each of the embodiments of the present disclosure are recited in the synthetic embodiment of the disclosure of Taiwan Patent Application No. 100147749.

The compound B is represented, for example, by one of the following formulas (1) to (9) or a combination thereof:

Wherein R ₁ is hydrogen, alkyl, alkylalkenyl, phenyl, dimethylamino, or -NH ₂ and R ₂ , R ₃ , R ₄ , and R ₅ are each independently hydrogen, alkyl, or a -NH _2.

Exemplary Compound B is an imidazole, imidazole derivative, pyrrole, pyrrole derivative, pyridine, 4- tert -butylpyridine, 3-butylpyridine, 4-dimethylaminopyridine, 2,4, 6-triamino-1,3,5-triazine, 2,4-dimethyl-2-imidazoline, pyridazine, pyrimidine, and pyradine.

[Table 1]

The compound A is represented, for example, by one of the following formulas (10) to (13) or a combination thereof:

(10)

(10)

Wherein n is an integer from 0 to 4;

R ₆ is -RCH ₂ R ', -RNHR-, -C (O) CH ₂ -, -R'OR "OR'-, -CH ₂ OCH ₂ -, -C (O) OO-, -S-, -SS-, -S ( O) -, -CH 2 S (O) CH 2 -, - (O) S (O) -, -C 6 H 4 -, -CH 2 ( C ₆ H ₄ ) CH ₂ -, -CH ₂ (C ₆ H ₄ ) (O) -, -C ₂ H ₄ - (NC ₂ H ₄ ) -C ₂ H ₄ , a siloxane group, Phenylene, or substituted biphenylene, R is C _{1 -4} alkylene, R 'is C _{1 -4} alkylene, biphenylene, or substituted biphenylene, and R "is C _{1 -4} Alkylene, -C ₆ H ₄ -C (CF ₃ ) ₂ -C ₆ H ₄ -, biphenylene, or substituted biphenylene;

R ₇ is selected from the group consisting of -RCH ₂ -, -CH ₂ - (O) -, -C (CH ₃ ) ₂ -, -O-, -OO-, -S-, _{-, C (CF 3) 2} -, or -S (O) -, in which R is a C _1-4 alkylene group.

R ₈ is hydrogen, C _{1 -4} alkyl, phenyl, benzyl, cyclohexyl, sulfonyl hydroxide, -C ₆ H ₄ CN, N- _{methoxycarbonyl, - (C 6 H 4)} -O (C 2 H ₄ O) -CH ₃ , C ₂ H ₄ - (C ₂ H ₄ O) ₁₁ -OCH ₃ , or -C (O) CH ₃ .

Examples of the compound A are shown in Table 2A below.

[Table 2A]

Other examples of the above formula (A) are shown in Table 2B below.

[Table 2B]

In another embodiment, the compound A may also be polyethylene glycol dimethacrylate, bis [[4- [(vinyloxy) methyl] cyclohexyl] methyl] isophthalate, or triallyl trimellitate.

In the third exemplary embodiment, the first and second metastable polymers used in the first nanoscale coating layer and the second nanoscale coating layer may be the same or different.

The method for synthesizing the metastable state polymer includes a step of dissolving the compound A in a solvent to form a mixed solution. The solvent includes a high-polarity solvent such as gamma -butyrolactone (GBL), ethylene carbonate (EC), propylene carbonate (PC), or N-methylpyrrolidone (NMP) , The high polarity solvent may provide a higher solubility to promote thermal polymerization of the reactants. In addition, the high polarity solvent can provide a flexible variation in solids content. This feature broadens the scope of application of the present disclosure.

Thereafter, the compound B is added to the mixed solution in several batches. Thereafter, thermal polymerization is carried out in the mixed solution. The molar ratio of compound A to compound B is, for example, from 10: 1 to 1:10, preferably from 1: 1 to 5: 1. The compound B may be added in the same or different amounts in 2 to 30 positions, preferably 4 to 16 positions. The addition time may be from 5 minutes to 6 hours per batch. Preferably, the time between additions of each batch is 15 minutes to 2 hours. The compound B may be added at a reaction temperature of 60 ° C to 150 ° C, preferably at a temperature of 120 ° C to 140 ° C. Further, the duration of action refers to the reaction time which is continued after the compound B is completely added, and the operation period may be 0.5 hours to 48 hours, preferably 1 hour to 24 hours.

The compound B is added in a plurality of batches (a plurality of times, i.e., two or more times) to the mixed solution containing the system of the compound A / solvent having the above reaction temperature, and then the thermal polymerization is performed, Gelation or reticular structure due to over reaction due to the simultaneous addition of materials can be prevented.

The metastable polymer synthesized by the method described above can be stored for a long time at room temperature (or at temperatures above room temperature), and the viscosity of the metastable polymer does not change rapidly after opening. In addition, the metastable state polymer retains some of the functional groups that can be reacted again, which can facilitate subsequent processing. The unreacted functional group may be reacted by heating as required or by applying a voltage. For example, if the temperature of the metastable-state nitrogen-containing polymer is 160 ° C to 200 ° C, another reaction can be induced to completely transform the macromolecule of the metastable polymer into a polymer.

4 is a schematic view of a lithium secondary battery according to a fourth exemplary embodiment of the present disclosure;

4, the lithium secondary battery 400 includes at least one electrode material, a non-aqueous electrolyte 402, and a separator 404 disposed in the non-aqueous electrolyte 402, Non-aqueous solvents and lithium salts. The electrode material of the fourth exemplary embodiment includes a cathode material 406 and a cathode material 408 and the composite electrode material of the lithium secondary battery referred to in the first to third exemplary embodiments includes a cathode material 406 And the cathode material 408, as shown in FIG. Of course, the composite electrode material of the lithium secondary battery mentioned in the first to third exemplary embodiments may also be used for both the cathode material 406 and the anode material 408. [ 4 shows only the anode material 406, the cathode material 408, the non-aqueous electrolyte 402, and the separator 404, but the present disclosure is not limited thereto.

Method for manufacturing composite anode of lithium secondary battery

When the cathode material 406 of the lithium secondary battery 400 is a composite electrode material of the lithium secondary battery mentioned in the first to third exemplary embodiments, its manufacturing method is exemplified as follows.

The cathode active material containing the metastable polymer in an amount of 0.005% to 10% (concentration ratio to the anode) is stirred in a planetary-type mixing machine or a regular machine for 3 to 10 minutes. Thereafter, a nanoscale layer having a thickness of about 1 nm to 30 nm is coated. The result is a composite cathode active material . The composite cathode active material, the conductive additive, and the binder are dissolved in NMP at a ratio of 80% to 95%, 3% to 15%, and 3% to 10%, respectively, and evenly mixed and stirred. The mixture is then evenly coated on an aluminum foil roll having a width of 35 cm and a thickness of 20 mu m. The dried anode roll was rolled and slit, and finally dried in vacuo at about 110 캜 for 4 hours. The cathode active material may be a lithium oxide, a lithium sulphide, a lithium selenide, a lithiated telluride, or a combination thereof. The compound may be selected from the group consisting of vanadium, titanium, chromium, copper, molybdenum, niobium, iron , Nickel, cobalt, and manganese. The conductive additive may be carbon black, graphite, acetylene black, nickel powder, aluminum powder, titanium powder, stainless steel powder, or a combination thereof. The binder may be a fluororesin binder such as polyvinylidene fluoride (PVDF), Teflon, styrene-butadiene rubber, polyamide, melamine resin, carboxymethylcellulose (CMC) binder or polyacrylate latex binder (LA 132) Lt; / RTI >

Method for manufacturing composite anode of lithium secondary battery

When the negative electrode material 408 of the lithium secondary battery 400 is a composite electrode material of the lithium secondary battery mentioned in the first to third exemplary embodiments, its manufacturing method is exemplified as follows.

The negative electrode active material containing the metastable polymer in an amount of 0.005% to 10% (concentration ratio to the negative electrode) is stirred in a planetary mixer or standard equipment for 3 minutes to 10 minutes. Thereafter, a nanoscale layer having a thickness of about 1 nm to 30 nm is coated. The result is composite anode active material . Then, the composite negative electrode active material, the conductive additive, and the binder are dissolved in NMP at a ratio of 90% to 95%, 1% to 10%, and 3% to 10%, respectively. After even mixing, the mixture is coated onto a copper foil roll having a width of 35 cm and a thickness of 10 m. The formed negative electrode roll was rolled and cut, and vacuum-dried at 110 캜 for 4 hours similarly to the positive electrode. The negative electrode active material may be MCMB, MGP, VGCF, CNT, coke, carbon black, graphite, acetylene black, carbon fiber, glassy carbon, SiC, lithium alloy, or a combination thereof. The negative electrode selected from the metal group may be, for example, Al, Zn, Bi, Cd, Sb, Si, Pb, Sn, Li ₃ FeN ₂ , Li _{2 .6} Co _{0 .4} N, Li _{2 .6} Cu _{0 . 4} N, or a combination thereof. In addition, the anode active material may be a metal oxide such as SnO ₂ , GeO ₂ , GeO ₂ , In ₂ O, In ₂ O ₃ , PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₃ O ₄ , AgO, Ag ₂ O, Ag ₂ O ₃ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , SiO ₂ , ZnO, CoO, NiO, FeO, TiO ₂ , Li ₃ Ti ₅ O ₁₂ , SiC, . The binder may be a fluororesin binder such as PVDF, Teflon, styrene-butadiene rubber, polyamide, melamine resin, CMC binder, or polyacrylate latex binder (LA 132).

In the fourth exemplary embodiment, the separator 404 is a PP / PE / PP triple layer film having a thickness of, for example, 10 mu m to 20 mu m.

Non-aqueous electrolyte and its production method

The nonaqueous electrolyte solution 402 of the fourth exemplary embodiment includes a lithium salt, an organic solvent, and the above-described metastable state polymer additive, wherein the metastable state polymer additive is present in an amount of 0.01 to 5% By weight.

Wherein the lithium salt is selected from the group consisting of LiPF ₆ , LiClO ₄ , LiBF ₄ , LiSO ₃ CF ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ CF ₂ CF ₃ ) ₂ , LiTFSI, LiAsF ₆ , LiSbF ₆ , LiAlCl ₄ , LiGaCl _{4, LiNO 3, LiC (SO} 2 CF 3) 3, LiSCN, LiO 3 SCF 2 CF 3, LiC 6 F 5 SO 3, LiO 2 CCF 3, LiSO 3 F, LiB (C 6 H 5) 4, LiB ( C ₂ O ₄ ) ₂ , or combinations thereof. The concentration of the lithium salt is 0.5 mol / L (M) to 1.5 mol / L (M).

The organic solvent may be at least one selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, dipropyl carbonate, acid anhydride, N-methylpyrrolidone, N-methylacetamide, N-methylformamide, dimethyl sulfoxide, 1,2-diethoxyethane, 1,2-dimethoxyethane, 1,2-dibutoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, Furan, propylene oxide, sulfite, sulfate, phosphonate, or derivatives thereof.

In addition, the organic solvent may include a carbonate, an ester, an ether, a ketone, or a combination thereof. The ester is selected from the group consisting of methyl acetate, ethyl acetate, methyl butyrate, ethyl butyrate, methyl propionate, ethyl propionate, and propyl acetate (PA). The carbonate includes EC, PC, diethyl carbonate (DEC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), vinylene carbonate, butylene carbonate, dipropyl carbonate or combinations thereof.

The lithium secondary battery 400 is manufactured by winding and rolling the anode material 406 (positive electrode or composite positive electrode), the negative electrode material 408 (negative electrode or composite negative electrode), and the separator 404 into a rectangular aluminum Placing in a foil bag housing, the dimensions of the housing being 38 mm x 3.5 mm x 62 mm. Then, the nonaqueous electrolyte solution 402 is filled in the housing.

In order to demonstrate the effectiveness of the disclosure, a plurality of examples and comparative examples are listed below. The following tests were conducted on the lithium half-cell or lithium cell produced: decomposition voltage test, capacity-voltage test, charge-discharge cycle test, scanning electron microscope (SEM) and transmission electron microscope (TEM).

"Disassembly voltage test"

Linear sweep voltammetry (LSV) consisted of continuously testing the current through the cell or electrode, and recording the change in potential over time. Here, the decomposition voltage of the non-aqueous electrolyte was measured at 3 V to 9 V at a scan rate of 0.5 mv / s with a Biological (VMP3) fixed potential device.

"Capacity-Voltage Test"

The C-V (Capacity-Voltage) curve describes the relationship between battery voltage and capacity during charging and discharging. In the first to fifth cycles, the cells were separately charged and discharged at a rate of 0.1 C (C-rate), 0.2 C, 0.5 C, 1 C, and 2 C to measure the capacity. First, the test was charged with a constant current (CC), then charged with a constant voltage (CV), and the constant voltage was 4.2V. At the same time, the test was performed with a cut off current of one-half the value of the constant current.

"Charge / Discharge Cycle Test"

The charge of 0.2C and the discharge at 0.5C were used to record changes in cell capacity after multiple charge and discharge cycles.

< Example  1>

First, a composite LiNi ₄ Co ₄ Mn ₂ O ₂ was used as a cathode material and a lithium metal was used as a cathode. At the same time, the composite LiNi ₄ Co ₄ Mn ₂ O ₂ was used _first as a cathode material, and lithium metal was used as a cathode. In addition, a regular electrolyte solution (1.1M LiPF ₆ EC / EMC / DEC) was used. The weight ratio of metastable polymer to all materials was about 0.5%.

The metastable polymer of Example 1 was formed by dissolving 3% of the oligomer of phenylmethane maleimide (Compound A) in NMP to form a mixed solution. Then, 2,4-dimethyl-2-imidazoline (Compound B) was added to the mixed solution in several batches, and thermal polymerization was carried out at 130 ° C for 8 hours. The molar ratio of the oligomer of 3% phenylmethane maleimide to the 2,4-dimethyl-2-imidazoline was 2: 1. Here, the metastable state polymer of Example 1 was obtained.

As shown in FIG. 17, the metastable polymer of Example 1 has a narrow molecular weight distribution and has a GPC (gel permeation chromatography) peak time of 20.2 minutes and a polydispersity index (PDI) of molecular weight Index) is 1.2. The definition of PDI of the molecular weight is the weight average molecular weight divided by the number average molecular weight.

In Example 1, the positive electrode active powder was LiNi ₄ Co ₄ Mn ₂ O ₂ , the conductive additive was carbon black (Super P ^® ), and the binder was PVDF. The metastable state polymer was directly coated on the cathode material by a mixing method, and then a TEM photograph of FIG. 5 was obtained by using a TEM to observe the composite cathode material of the obtained lithium secondary battery. The TEM photograph shows that the surface of the positive electrode active powder has a nanoscale coating layer having a thickness of about 2 nm to 5 nm as a nanoscale coating layer.

Thereafter, a lithium secondary battery was manufactured according to the method of the fourth exemplary embodiment. As shown in FIG. 6, the capacity test of the battery cycle life (Test 1) was carried out at a high temperature (about 55 ° C) and a voltage of 2.8 V to 4.3 V using the composite cathode material of the lithium secondary battery. The results showed that the specific capacity was still maintained even when the cycle number reached 70 cycles. In addition, even after 150 cycles, the capacity could still reach over 150 mAh / g, indicating a maintenance rate of over 82%.

Comparative Example  One

Also, the uncoated cathode material was used to perform the capacity test of the battery cycle life under the same temperature condition and the normal voltage range of 2.8 V to 4.2 V as in Example 1. Similar to Example 1, the results are shown in FIG. 6 (Test 2), with a much lower capacity than Test 1 in Example 1. In addition, a capacity test of battery cycle life (Test 3) was performed using uncoated cathode materials under the same temperature conditions but at a voltage of 2.8 V to 4.4 V. [ The results showed that when the number of cycles reached 70, the capacity was substantially reduced, and after the number of cycles reached 150, the capacity was reduced to a very poor level.

It can be seen from FIG. 6 that when the charge voltage is increased from 4.2 V to 4.4 V, the composite cathode material of the lithium secondary battery comprising the coated nanoscale coating layer has an apparently stable cycle life and a significantly increased energy density have.

< Example  2>

The composite LiNi ₄ Co ₄ Mn ₂ O ₂ of Example 1 was used as the cathode material and lithium metal was used as the cathode. A standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) was used. The weight ratio of the metastable polymer to the composite electrode material of the lithium secondary battery was individually changed to 1% (Test 1), 0.75% (Test 2), and 0.5% (Test 3). Under the voltage conditions of 2.8 V to 4.4 V at 55 캜, the cells were independently charged to 0.2 C and discharged to 0.5 C to obtain the curve of FIG. 7 between battery cycle life and capacity.

Comparative Example  2

In addition, uncoated LiNi ₄ Co ₄ Mn ₂ O ₂ was used as the cathode material and lithium metal was used as the cathode material. In addition, a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) was used. Similar to Example 2, the battery was charged to 0.2 C and discharged at 0.5 C under a voltage condition of 2.8 V to 4.4 V at 55 캜. The result (Test 4) is shown in Fig. 7 similarly to Example 2. Fig.

It can be seen from Fig. 7 that the cycle life of the uncoated cathode material was considerably shortened and the capacity was also considerably reduced. On the other hand, for a composite cathode material of a lithium secondary battery having a nanoscale coating layer coated on its surface, in a test example in which the weight ratio of the electrode material of the metastable polymer was 0.5%, 0.75%, and 1% Stable cycle life was maintained. Even when the number of cycles reached 100, the capacity still remained at 88%. Thus, each test embodiment has an apparently stable cycle life.

< Example  3>

The composite LiNi ₄ Co ₄ Mn ₂ O ₂ of Example 1 Was used as a cathode material, and lithium metal was used as a cathode. In addition, a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) was used. A capacity test (Test 1) for the battery was performed at a high operating voltage at room temperature and at different voltages (including 4.2V, 4.3V, 4.4V, 4.5V, and 4.6V). The results are shown in Fig.

In addition, the composite LiNi ₄ Co ₄ Mn ₂ O ₂ of Example 1 Was used as a cathode material, and lithium metal was used as a cathode. In addition, an electrolyte (1.1 M LiPF ₆ EC / EMC / DEC) containing 1.5% metastable polymer additive was used. Under the same test conditions as Test 1 of Example 3, a capacity test (Test 2) was performed on the battery at a high operating voltage. The results are shown in Fig.

Comparative Example  3

Thereafter, a capacity test (Test 3) was performed for a cell having a cathode material containing only uncoated anode LiNi ₄ Co ₄ Mn ₂ O ₂ and a lithium metal anode together with a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) Under the same test conditions as in Example 3. The results are shown in Fig.

From Figure 8 it can be seen that at test voltages of 4.2V, 4.3V, 4.4V, 4.5V, and 4.6V both the capacities of Test 1 and Test 2 are higher than the capacities of Test 3. The composite LiNi ₄ Co ₄ Mn ₂ O ₂ cathode material produced a capacity of greater than 16% at high operating voltage.

< Example  4>

The composite LiNi ₄ Co ₄ Mn ₂ O ₂ cathode material of Example 1 and the MGP anode were assembled with a 18650 large battery together with a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC). Thereafter, the 18650 mass cell was independently charged and discharged at 1 C and 3 C under a voltage condition of 2.8 V to 4.3 V at 55 캜. The results are shown in Fig. Simultaneously, the initial composite cathode material of the lithium secondary battery and the surface of the cathode material and the cathode material (graphite carbon material) after 100 cycles (1C) were observed by SEM. 10a of the initial cathode material, Fig. 10b of the cathode material after a plurality of cycles, and Fig. 10c of the cathode material after a plurality of cycles were obtained.

Comparative Example  4

In addition to the standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC), uncoated LiNi ₄ Co ₄ Mn ₂ O ₂ The anode material and the MGP anode material were assembled into a 18650 mass cell. Thereafter, the 18650 mass cell was independently charged and discharged at 1 C and 3 C under a voltage condition of 2.8 V to 4.3 V at 55 캜. The results are shown in Fig. 9 similarly to Example 4. Fig. Simultaneously, the initial uncoated composite cathode material and the surface of the cathode material and the cathode material (graphite carbon material) after 100 cycles (1C) were observed by SEM. 11a of the initial cathode material, Fig. 11b of the cathode material after a plurality of cycles, and Fig. 11c of the cathode material after a plurality of cycles were obtained.

 9, the composite cathode material of a lithium secondary battery having a nanoscale coating layer on its surface has a significantly higher capacity retention in a high temperature cycle life test than a composite cathode material without a nanoscale coating layer. .

Further, from the SEM photograph, after 100 charge and discharge cycles, the thickness of the coating layer of the composite cathode material of the lithium secondary battery having the nanoscale coating layer on the surface is thicker, and the coating layer is uniformly coated on the positive electrode active powder ) Were observed. However, the surface of the uncoated cathode material was unchanged (see FIG. 11B). From the SEM photograph of the surface of the negative electrode material, it was observed that the negative electrode material of the large capacity battery composed of uncoated positive electrode material cracked (see FIG. 11C). However, in the case of the cathode material of a lithium secondary battery having a nanoscale coating layer on its surface, the integrity of the cathode material of the battery was maintained (see Fig. 10c), which presumably reflected the ability of the cathode material to stabilize the SEI composition .

< Example  5>

First, mesocarbon microbeads (MCMB) were prepared and used as a negative electrode active material. The MCMB negative electrode to which 0.5% of the metastable polymer (concentration ratio to the negative electrode) was added was stirred for 3 to 10 minutes in a planetary mixer or standard equipment. A nanoscale layer having a thickness of about 1 nm to 30 nm was coated and the result was a mesocarbon microbead (MCMB) anode active material.

First, 4,4'-diphenylmethane bismaleimide and 2,2-bis (4- (p-maleimidophenoxy) -phenyl) -hexafluoropropane were dissolved in NMP in a molar ratio of 2: 1, 3% mixed solution to form the metastable polymer of Example 5. Then, 2,4-dimethyl-2-imidazoline was added to the mixed solution in several batches, and thermal polymerization was carried out at 130 캜 for 8 hours. The molar ratio of the 3% mixed solution to the 2,4-dimethyl-2-imidazoline was 2: 1. Here, the metastable state polymer of Example 5 was obtained.

As shown in FIG. 18, the metastable state nitrogen-containing polymer of Example 5 is a polymer having a narrow molecular weight distribution and having a GPC peak time of 20.6 minutes and a molecular weight of 1.2 PDI.

The conductive additive of Example 5 was Super P and the binder was PVDF.

Hereinafter, the production of the composite cathode of the lithium secondary battery is as described in the fourth exemplary embodiment. The thickness of the nanoscale coating layer of the composite anode material of the lithium secondary battery was about 5 nm to 10 nm. Then, with the standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC), the negative electrode and LiCoO ₂ The positive electrode was assembled into a full cell. The pull cells were charged at 0.2 C under a voltage of 2.8 V to 4.3 V at room temperature and discharged to 0.5C. A curve diagram of Fig. 12 between the battery cycle life and the discharge capacity was obtained.

Comparative Example  5

In addition, an uncoated MCMB was used as a negative electrode material, LiCoO ₂ was used as a positive electrode material, and a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) was used. Similar to Example 5, the cells were charged to 0.2 C and discharged to 0.5 C under the same voltage conditions of 2.8 V to 4.3 V at room temperature. The results are shown in FIG. 12 similarly to Example 5.

From Fig. 12, it can be seen that when the number of cycles reaches 110, the capacity retention of a cell having only a nanoscale coating layer containing only a metastable polymer is 82%. On the other hand, the capacity retention ratio of the cells not having a nanoscale coating layer on both the positive electrode and the negative electrode was only 70%.

< Example  6>

First, MGP was prepared and used as an anode active material. Thereafter, the MGP negative electrode active material to which the metastable polymer of 0.5% (ratio to the negative electrode) was added was agitated in a planetary mixer or standard equipment for 3 minutes to 10 minutes. Thereafter, a nanoscale layer of 1 nm to 30 nm was coated. The metastable polymer of this example was the same as the metastable polymer of Example 5.

A TEM photograph of FIG. 13 was obtained by using a TEM to observe the composite negative electrode active material of the obtained lithium secondary battery. The TEM photograph shows that the surface of the positive electrode active powder has a nanoscale coating layer and its thickness is about 5 nm to 10 nm.

Example  7

First, a composite LiCoO ₂ was prepared and used as a cathode material, and lithium metal was used as a cathode. In addition, a standard electrolyte (1.1M LiPF ₆ EC / EMC / DEC) was used. The weight ratio of metastable polymer to all cathode materials was 1% (test 1) and 0.5% (test 2). The metastable polymer was directly coated on the cathode material by a mixing method.

4,4'-diphenylsulfone bismaleimide and 2,2-bis (4- (p-maleimidophenoxy) -phenyl) -hexafluoropropane were dissolved in EC / PC at a molar ratio of 4: 1, 3% mixed solution was formed to form the metastable polymer of Example 7. Then, 2,4-dimethyl-2-imidazoline was added to the mixed solution in several batches, and thermal polymerization was carried out at 130 캜 for 8 hours. The molar ratio of the 3% mixed solution to the 2,4-dimethyl-2-imidazoline was 2: 1. Here, the metastable state polymer of Example 7 was obtained.

As shown in FIG. 19, the metastable state nitrogen-containing polymer of Example 7 is a polymer having a narrow molecular weight distribution and having a GPC peak time of 21 minutes and a molecular weight of PDI of 1.6.

Thereafter, as shown in FIG. 14, a capacity test of the battery cycle life was performed on the composite cathode material of the lithium secondary battery manufactured using the above-described method at a high temperature (about 55 ° C) and a voltage of 2.8 V to 4.3 V . The results show that even when the number of cycles reaches 100, a certain amount of capacity is still maintained, which represents a maintenance rate of over 80%.

Comparative Example  6

Further, uncoated LiCoO ₂ A capacity test of the battery cycle life was performed under the same temperature conditions as in Example 7 and a normal voltage range of 2.8 V to 4.3 V using the anode material. The results are shown in Figure 14 (Test 3), similar to Example 7, with a much lower capacity compared to Test 1. In addition, the results of using uncoated cathode materials showed that when the number of cycles reached 100, the capacity was significantly reduced and the retention rate of capacity was only 60%.

14, when the charge voltage is increased from 4.2 V to 4.3 V, the composite LiCoO ₂ of the lithium secondary battery including the coated nanoscale coating layer It can be seen that the anode material has an apparently stable cycle life and a significantly increased energy density.

Example  8

An electrochemical linear scanning voltage method (LSV) test was conducted using a coin cell (size CR2032), where the cell anode was a composite LiCoO ₂ of Example 7 An anode was used, the cathode was lithium metal, and the separator was a PP / PE / PP triple layer film. 1.1 M of LiPF ₆ was dissolved in EC / DEC / EMC to form an electrolytic solution. The linear scan potential ranged from 3 V to 9 V and the scan rate was 0.5 mV / s. As shown in FIG. 15, it was observed that the decomposition potential of the electrolytic solution of the lithium secondary battery having the composite anode exceeded 9 V.

Example  9

An electrochemical linear scanning voltage (LSV) test was conducted using a coin cell (standard CR2032), where the battery anode was coated with a composite LiNi ₄ Co ₄ Mn ₂ O ₂ An anode was used, the cathode was lithium metal, and the separator was a PP / PE / PP triple layer film. 1.1 M of LiPF ₆ was dissolved in EC / DEC / EMC to form an electrolytic solution.

The metastable polymer of Example 9 was the metastable polymer of Example 1.

The linear scan potential ranged from 3 V to 9 V and the scan rate was 0.5 mV / s. As shown in FIG. 16, the decomposition potential of the electrolyte of the lithium secondary battery having the composite anode was observed to exceed 5.7 V.

Comparative Example  7

Electrochemical linear scanning voltage (LSV) tests were performed using a button cell (standard CR2032), where the cell anode was an uncoated LiNi ₄ Co ₄ Mn ₂ O ₂ Electrode was used, the cathode was lithium metal, and the separator was a PP / PE / PP triple layer film. 1.1 M of LiPF ₆ was dissolved in EC / DEC / EMC to form an electrolytic solution. The linear scan potential ranged from 3 V to 9 V and the scan rate was 0.5 mV / s. As shown in FIG. 16, the decomposition potential of the electrolytic solution of Comparative Example 7 was found to be only 5.7 V.

In addition, since the presence of the nanoscale coating layer significantly increases the decomposition voltage of the electrolyte solution, decomposition of the electrolyte solution in a high-voltage environment is prevented.

On the basis of the above description, for a composite electrode material of a lithium secondary battery and a lithium secondary battery, the nanoscale coating layer formed on the anode surface can reduce the reaction progress due to the direct contact between the electrolyte and the electrode, Can be effectively improved, and the operating voltage can be increased to increase the energy density of the battery. The nanoscale coating layer formed on the cathode effectively improves the compatibility between the electrode and the electrolyte, thereby inhibiting the destructive insertion of the highly polar solvent into the cathode material. In general, the cycle life at high temperature is effectively increased, the capacity retention rate is significantly increased, and the manufacturing process is simple, which can reduce the cost.

It will be apparent to those skilled in the art that various changes and modifications can be made to the structure of the described embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover the modifications and variations of this disclosure provided they fall within the scope of the following claims and their equivalents.

Claims (27)

A composite electrode material for a lithium secondary battery,
Electrode active powder; And
A nanoscale coating layer coated on the surface of the electrode active powder, wherein the nanoscale coating layer is formed from a metastable state polymer, the metastable polymer is formed from a reaction of a compound A and a compound B, Compound A was prepared by reacting 4,4'-diphenylmethane bismaleimide, an oligomer of phenylmethane maleimide, m-phenylene bismaleimide, 2,2'-bis [4- (4-maleimidophenoxy) , 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimide - (2,2,4-trimethyl) hexane, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 1,3-bis (3-maleimidophenoxy) Benzene, 2,2-bis (4- (p-maleimidophenoxy) -phenyl) -hexafluoropropane, 2,2-bis (p-maleimidophenoxy) Lt; / RTI &gt; phenyl) -hexafluoroprop &lt; RTI ID = 0.0 & , Poly (ethylene glycol (11)) which is terminated with 1,8-bis-maleimidodiethylene glycol, tris (2-maleimidoethyl) amine, 4-maleimido-phenylmethyl diether, 4-maleimidophenol Maleimido-benzenesulfonic acid, poly (ethylene glycol (11)), 2-maleimidomo propyleneglycol 1- (2-methoxyethyl) ether, 2-maleimidoethylmethyl diether, (Dimethylsiloxane), 5 - (2 - methoxy - ethoxy) -5H - furan - 2 - one, which is terminated with 2 - maleimidopropyl methyl ether, bis (3 - maleimido - propyl - dimethylsilyl) Methylene] cyclohexyl] methyl] iso (2-methoxyethoxy) -cyclohex-2-ene-1,4-dione, polyethylene glycol dimethacrylate, bis [ Phthalate, or triallyl trimellitate, and the compound B is represented by one of the following chemical formulas (1) to (8) and is used as an initiator It said, the nanoscale coating nanoscale coating layer at a weight ratio of 0.5% to 1% for the composite electrode material of the lithium secondary battery; lithium composite electrode material for a secondary battery comprising:

Wherein R ₁ is hydrogen, alkyl, alkylalkenyl, phenyl, dimethylamino, or -NH ₂ and R ₂ , R ₃ , R ₄ , and R ₅ are each independently hydrogen, alkyl, or a -NH _2. The method according to claim 1,
Wherein the molar ratio of the compound A to the compound B is 1: 1 to 5: 1. delete The method according to claim 1,
Wherein said compound B is selected from the group consisting of imidazole, pyrrole, pyridine, 4- tert -butylpyridine, 3-butylpyridine, 2,4,6-triamino- A complex electrode material for a lithium secondary battery, wherein the composite electrode material is selected from the group consisting of azolines, pyridazines, pyrimidines, and pyrazines. delete The method according to claim 1,
Wherein the electrode active powder comprises a cathode material. The method according to claim 6,
Wherein the nanoscale coating layer has a thickness of 1 nm to 30 nm. The method according to claim 6,
Wherein the cathode material is selected from the group consisting of lithiumated oxides, lithiated sulfides, lithiated selenides, tellurides of lithiumated vanadium, titanium, chromium, copper, molybdenum, niobium, iron, nickel, cobalt, manganese, &Lt; tb &gt;&lt; / TABLE &gt; The method according to claim 6,
Wherein the cathode material comprises LiMn ₂ O ₄ , LiNi _x Co _y O ₂ , LiCoO ₂ , LiFePO ₄ , LiNi _x Co _y Mn _z O ₂ , or LiNi _x Mn _y O ₂ . The method according to claim 1,
Wherein the electrode active powder comprises a negative electrode material. 11. The method of claim 10,
Wherein the nanoscale coating layer has a thickness of 1 nm to 30 nm. 11. The method of claim 10,
Wherein the anode material is selected from the group consisting of mesocarbon microbeads (MCMB), mesophase graphite powder (MGP), vapor grown carbon fibers (VGCF), carbon nanotubes (CNT), coke, carbon black, natural graphite, artificial graphite, Fibers, glassy carbon, lithium alloys, and combinations thereof. A composite electrode material for a lithium secondary battery,
An electrode plate made of an electrode active powder; And
A first nanoscale coating layer coated on a surface of the electrode plate,
Wherein the first nanoscale coating layer is formed from a first metastable polymer,
The first metastable polymer is produced from the reaction of compound A and compound B,
The compound A was prepared by reacting 4,4'-diphenylmethane bismaleimide, an oligomer of phenylmethane maleimide, m-phenylene bismaleimide, 2,2'-bis [4- (4-maleimidophenoxy) phenyl] Propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, (2,2,4-trimethyl) hexane, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 1,3-bis (3-maleimidophenoxy) Benzene, 1,3-bis (4-maleimidophenoxy) benzene, 2,2-bis (4- (p- maleimidophenoxy) -phenyl) -hexafluoropropane, 2,2- Maleimido-phenyl) -hexafluoropropane, 1,8-bis-maleimidodiethylene glycol, tris (2-maleimidoethyl) amine, poly (ethylene glycol 11)), 4-maleimidophenol, 4-maleimido-benzenesulfonic acid, 2-maleimidoethylmethyl diether (3-maleimido-propyl) -propyl methyl ether, ethylene glycol 2-maleimidopropyl methyl ether, bis (3-maleimido-propyl- (Dimethylsiloxane), 5- (2-methoxy-ethoxy) -5H-furan-2-one, 5- (2-methoxy-ethoxy) -cyclohex- Methyl-1, 4-dione, polyethylene glycol dimethacrylate, bis [4- (vinyloxy) methyl] cyclohexyl] methyl] isophthalate, or triallyl trimellitate, A first nanoscale coating layer represented by one of the following formulas (1) to (8) and used as an initiator, wherein the weight ratio of the first nanoscale coating layer to the composite electrode material of the lithium secondary battery is 0.5% to 1% Composite Electrode Material of Lithium Secondary Battery Including:

Wherein R ₁ is hydrogen, alkyl, alkylalkenyl, phenyl, dimethylamino, or -NH ₂ and R ₂ , R ₃ , R ₄ , and R ₅ are each independently hydrogen, alkyl, or a -NH _2. 14. The method of claim 13,
Wherein the second nanoscale coating layer is formed from a second meta-stable polymer, and the second meta-stable polymer is a second nanoscale coating layer disposed on the surface of the electrode active powder, Wherein the second nanoscale coating layer is formed from a reaction between the first nanoscale coating layer and the second nanoscale coating layer, and the second nanoscale coating layer is 0.5% to 1% of the composite electrode material of the lithium secondary battery. 15. The method of claim 14,
Wherein the molar ratio of the compound A to the compound B is 1: 1 to 5: 1. delete 16. The method of claim 15,
Wherein said compound B is selected from the group consisting of imidazole, pyrrole, pyridine, 4- tert -butylpyridine, 3-butylpyridine, 2,4,6-triamino- A complex electrode material for a lithium secondary battery, wherein the composite electrode material is selected from the group consisting of azolines, pyridazines, pyrimidines, and pyrazines. delete 14. The method of claim 13,
Wherein the electrode active powder comprises a cathode material. 20. The method of claim 19,
Wherein the thickness of the first nanoscale coating layer is 1 nm to 30 nm. 20. The method of claim 19,
Wherein the cathode material is selected from the group consisting of lithiumated oxides, lithiated sulfides, lithiated selenides, tellurides of lithiumated vanadium, titanium, chromium, copper, molybdenum, niobium, iron, nickel, cobalt, manganese, &Lt; tb &gt;&lt; / TABLE &gt; 20. The method of claim 19,
Wherein the cathode material comprises LiMn ₂ O ₄ , LiNi _x Co _y O ₂ , LiCoO ₂ , LiFePO ₄ , LiNi _x Co _y Mn _z O ₂ , or LiNi _x Mn _y O ₂ . 14. The method of claim 13,
Wherein the electrode active powder comprises a negative electrode material. 24. The method of claim 23,
Wherein the thickness of the first nanoscale coating layer is 1 nm to 30 nm. 24. The method of claim 23,
Wherein the negative electrode material is selected from the group consisting of MCMB, VGCF, CNT, coke, carbon black, natural graphite, artificial graphite, acetylene black, carbon fiber, vitreous carbon, lithium alloy and combinations thereof. An electrode material comprising at least one electrode material, wherein the electrode material is a composite electrode material of the lithium secondary battery of claim 1;
A nonaqueous electrolyte solution in contact with the electrode material, wherein the nonaqueous electrolyte solution comprises a nonaqueous solvent and a lithium salt; And
And a separator disposed in the non-aqueous electrolyte. An electrode material comprising at least one electrode material, wherein the electrode material is a composite electrode material of the lithium secondary battery of claim 13;
A nonaqueous electrolyte solution in contact with the electrode material, wherein the nonaqueous electrolyte solution comprises a nonaqueous solvent and a lithium salt; And
And a separator disposed in the non-aqueous electrolyte.

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