KR20190055733A - Electrolyte additive for lithium battery, electrolyte solution comprising additive and Lithium battery comprising additive - Google Patents

Abstract

Provided are: a lithium battery electrolyte additive which is a sulfone-based compound represented by chemical formula 1; and organic electrolytic solution and a lithium battery including the same. In chemical formula 1, R_1 is an alkyl group having 1 to 5 carbon atoms substituted or unsubstituted with halogen, a cycloalkyl group having 4 to 10 carbon atoms substituted or unsubstituted with halogen, an aryl group having 5 to 10 carbon atoms substituted or unsubstituted with halogen, or a heteroaryl group having 2 to 10 carbon atoms substituted or unsubstituted with halogen. R_2 is an alkenyl group having 2 to 10 carbon atoms substituted or unsubstituted with halogen. The present invention can improve stability.

Description

[0001] The present invention relates to a lithium battery electrolyte additive, an organic electrolytic solution containing the same, and a lithium battery including the lithium battery additive,

A lithium battery electrolyte additive, an organic electrolytic solution containing the same, and a lithium battery.

Lithium batteries are used as power sources for portable electronic devices such as video cameras, mobile phones, and notebook computers. The rechargeable lithium secondary battery has three times higher energy density per unit weight than conventional lead batteries, nickel-cadmium batteries, nickel metal hydride batteries and nickel-zinc batteries.

A cathode active material is used which provides an increased discharge capacity to produce a lithium secondary battery having a high energy density. The cathode active material having an increased discharge capacity has a relatively low electrochemical stability. Therefore, during the charging / discharging process of the lithium secondary battery, a side reaction occurs between the cathode active material and the electrolyte, thereby deteriorating the stability of the lithium secondary battery. Therefore, there is a need for a method for improving the stability of a lithium secondary battery comprising a cathode active material that provides an increased discharge capacity.

One aspect is to provide a new lithium battery electrolyte additive.

Another aspect is to provide an organic electrolytic solution.

Another aspect is to provide a lithium battery.

According to one aspect,

There is provided a lithium battery electrolyte additive which is a sulfonic compound represented by the following general formula:

≪ Formula 1 >

In this formula,

R ₁ is an alkyl group having 1 to 5 carbon atoms which is substituted or unsubstituted with halogen, a cycloalkyl group having 4 to 10 carbon atoms which is substituted or unsubstituted with halogen, or an aryl group having 5 to 10 carbon atoms which is substituted or unsubstituted with halogen, A substituted or unsubstituted heteroaryl group having 2 to 10 carbon atoms,

R ₂ is an alkenyl group having 2 to 10 carbon atoms which is substituted or unsubstituted with halogen.

According to another aspect,

Lithium salts; Organic solvent; And

An organic electrolytic solution containing the above-mentioned additive is provided.

According to another aspect,

A cathode comprising a cathode active material;

A negative electrode comprising a negative electrode active material; And

And an organic electrolyte disposed between the anode and the cathode,

There is provided a lithium battery in which the organic electrolytic solution contains the above-mentioned additive.

According to one aspect, by employing an organic electrolytic solution containing a sulfonic compound, the side reaction of the lithium battery is suppressed and the life characteristic is improved.

1 is a schematic diagram of a lithium battery according to an exemplary embodiment.
Description of the Related Art
1: Lithium battery 2: cathode
3: anode 4: separator
5: Battery case 6: Cap assembly

Hereinafter, an electrolyte additive for a lithium battery according to exemplary embodiments, an organic electrolyte containing the same, and a lithium battery employing the organic electrolyte will be described in more detail.

An electrolyte additive for a lithium battery according to an embodiment is a sulfone compound represented by the following formula (1):

≪ Formula 1 >

Wherein R ₁ is an alkyl group having 1 to 5 carbon atoms which is substituted or unsubstituted with halogen, a cycloalkyl group having 4 to 10 carbon atoms which is substituted or unsubstituted with halogen, or an aryl group having 5 to 10 carbon atoms Or a heteroaryl group having 2 to 10 carbon atoms which is substituted or unsubstituted with halogen and R ₂ is an alkenyl group having 2 to 10 carbon atoms which is substituted or unsubstituted with halogen.

Nickel, and at least one other transition metal, and a lithium transition metal oxide having a nickel content of 80 mol% or more based on the total molar amount of the transition metal is used as a cathode active material, a lithium battery having a high output and a high capacity can be produced. Generally, in a lithium battery, a lithium transition metal oxide having a high content of nickel has an unstable surface structure, so that generation of gas due to side reaction during charging and discharging of the battery increases, and elution of transition metals such as nickel is further intensified. Therefore, the lifetime characteristics of the lithium battery are deteriorated.

On the other hand, the lithium battery including the electrolyte additive for lithium battery according to one embodiment described above suppresses an increase in initial resistance, suppresses generation of gas due to side reaction, and improves life characteristics.

For example, the sulfone-based compound represented by the formula (1) may be a sulfone-based compound represented by the following formula (2)

(2)

Wherein R ₃ is an alkyl group having 1 to 5 carbon atoms which is substituted or unsubstituted with halogen or an aryl group having 5 to 10 carbon atoms which is substituted or unsubstituted with halogen, and R ₄ is a covalent bond, an alkylene group having 1 to 5 carbon atoms , Or an alkenylene group having 2 to 10 carbon atoms.

For example, the sulfone-based compound represented by the formula (1) may be a sulfone-based compound represented by the following formulas (3) to (9)

(3) ≪ Formula 4 >

≪ Formula 5 > (6)

≪ Formula 7 > (8)

≪ Formula 9 >

An organic electrolytic solution according to another embodiment includes a lithium salt; Organic solvent; And the above-mentioned additives.

Since the organic electrolyte includes the above-described electrolyte additive for lithium batteries, increase in initial resistance of a lithium battery including an organic electrolytic solution is suppressed, gas generation due to side reactions is suppressed, and lifetime characteristics are improved.

For example, in the organic electrolytic solution, the content of the sulfonic compound represented by the general formulas (1) to (9) is limited to 3 wt% or less based on the total weight of the organic electrolytic solution, thereby suppressing gas generation due to side reactions and further improving the lifetime characteristics of the lithium battery do.

In the organic electrolytic solution, the content of the sulfonic compound represented by the general formulas (1) to (9) is 0.1 to 3 wt%, 0.1 to 2.9 wt%, 0.1 wt% to 2.8 wt%, 0.1 wt% To 2.7 wt%, 0.1 wt% to 2 wt%, 0.1 wt% to 1.5 wt%, or 0.2 wt% to 1 wt%. When the content of the sulfonic compound represented by the general formulas (1) to (9) is within this range, a lithium battery having gas generation suppressed and having excellent lifetime characteristics can be provided. Therefore, gas generation can be suppressed without substantial change in lifetime characteristics.

The organic solvent contained in the organic electrolytic solution may include, for example, a cyclic carbonate compound represented by the following formula (17): < EMI ID =

≪ Formula 17 >

Wherein X ₁ and X ₂ are independently of each other hydrogen or halogen, and at least one of X ₁ and X ₂ is F.

By including the cyclic carbonate compound represented by the above formula (17) in the organic solvent, lifetime characteristics and resistance suppressing effect of the lithium battery can be improved. For example, in the cyclic carbonate compound represented by the general formula (17), X ₁ may be hydrogen and X ₂ may be F.

The content of the cyclic carbonate compound represented by the general formula (17) may be 10 vol% or less, 9 vol% or less, 0.1 to 8 vol% or less, 7 vol% or less, 6 vol% or less, or 5 vol% or less based on the total volume of the organic solvent. For example, the content of the cyclic carbonate compound represented by the general formula (17) is 0.1 to 10 vol%, 0.1 to 9 vol%, 0.1 to 8 vol%, 0.1 to 7 vol%, 0.1 to 6 vol%, or 0.1 To 5 vol%. When the content of the cyclic carbonate compound represented by the general formula (17) is in this range, the lifetime characteristics and the resistance suppressing effect of the lithium battery can be further improved.

The organic electrolytic solution may further comprise a cyclic carbonate compound represented by the following formula (18): < EMI ID =

≪ Formula 18 >

In the above formula, X ₃ and X ₄ are, independently of each other, hydrogen, halogen or an alkyl group having 1 to 3 carbon atoms.

By including the cyclic carbonate compound represented by the general formula (18) in the organic electrolytic solution, lifetime characteristics and resistance suppressing effect of the lithium battery can be improved. For example, in the cyclic carbonate compound represented by the general formula (18), X ₃ and X ₄ may be hydrogen.

The content of the cyclic carbonate compound represented by the general formula (18) may be 3 wt% or less, 2.5 wt% or less, 2 wt% or less, or 1.5 wt% or less based on the total weight of the organic electrolytic solution. For example, the content of the cyclic carbonate compound represented by the general formula (18) may be 0.1 to 3 wt%, 0.1 to 2.5 wt%, 0.1 to 2 wt%, or 0.1 to 1.5 wt% based on the total weight of the organic electrolytic solution. When the content of the cyclic carbonate compound represented by the general formula (18) is within this range, the lifetime characteristics and resistance suppressing effect of the lithium battery can be further improved.

The organic solvent may be at least one selected from a carbonate-based solvent, an ester-based solvent, an ether-based solvent, and a ketone-based solvent.

(EMC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), propylene carbonate (PC) Ethyl carbonate, ethyl acetate, n-propyl acetate, dimethylacetate, methyl ethyl ketone, methyl ethyl ketone, methyl ethyl ketone, Gamma-butyrolactone, decanolide, gamma valerolactone, mevalonolactone, caprolactone, and the like can be used. As the ether solvent, dibutyl ether, tetraglyme, Dimethoxyethane, 2-methyltetrahydrofuran, tetrahydrofuran and the like can be used. As the ketone solvent, cyclohexanone and the like may be used , And the like acetonitrile (AN), three Sino nitrile (SN), adiponitrile can be used as the nitrile type solvent. As other solvents, dimethylsulfoxide, dimethylformamide, dimethylacetamide, tetrahydrofuran and the like can be used, but not limited thereto, and any solvent which can be used in the art can be used. For example, the organic solvent may include 50 to 95 vol% of chain carbonate and 5 to 50 vol% of cyclic carbonate, 55 to 95 vol% of chain carbonate and 5 to 45 vol% of cyclic carbonate, 60 to 95 vol% of chain carbonate, 5 to 40 vol% of chain carbonate, 65 to 95 vol% of chain carbonate and 5 to 35 vol% of cyclic carbonate, or 70 to 95 vol% of chain carbonate and 5 to 30 vol% of cyclic carbonate. For example, the organic solvent can be mixed for three or more organic solvents each day.

For example, the organic electrolytic solution contains 0.1 to 3.0% by weight of the sulfonic compound represented by the following general formulas (3) to (9) and 0.1 to 2.0% by weight of the compound represented by the following general formula (18a) And 1 to 10 vol% of the compound represented by 17a:

(3) ≪ Formula 4 >

≪ Formula 5 > (6)

≪ Formula 7 >

(8) ≪ Formula 9 >

<Formula 17a> <Formula 18a>

Lithium salts are _{LiPF 6, LiBF 4, LiCF 3} SO 3, Li (CF 3 SO 2) 2 N, LiC 2 F 5 SO 3, Li (FSO 2) 2 N, LiC 4 F 9 SO 3, LiN (SO 2 CF ₂ CF ₃ ) ₂ , and compounds represented by the following formulas (19) to (22):

(19) (20)

&Lt; Formula 21 > (22)

The concentration of the lithium salt may be 0.01 to 5.0 M, 0.05 to 5.0 M, 0.1 to 5.0 M, or 0.1 to 2.0 M, but is not necessarily limited to such a range and an appropriate concentration may be used if necessary. Within this concentration range, improved battery characteristics can be obtained.

The organic electrolytic solution may not contain a cyclic acid anhydride such as succinic anhydride. The organic electrolytic solution may not contain cyclic sulfone. The organic electrolytic solution may not contain a cyclic sulfonate. The organic electrolytic solution may not contain sultone.

A lithium battery according to another embodiment includes a positive electrode including a positive electrode active material; A negative electrode comprising a negative electrode active material; And an organic electrolytic solution disposed between the anode and the cathode, wherein the organic electrolytic solution includes the above-described additive.

By including the above-described electrolyte additive for a lithium battery, the initial resistance increase of the lithium battery is suppressed, the gas generation due to the side reaction is suppressed, and the lifetime characteristic is improved. Lithium transition metal oxide. In the lithium transition metal oxide containing nickel and other transition metals, the content of nickel is at least 60 mol%, at least 65 mol%, at least 70 mol%, at least 75 mol%, at least 80 mol%, at least 82 mol%, at least 85 mol % Or more, 87 mol% or more, or 90 mol% or more.

For example, a lithium transition metal oxide may be represented by the following formula:

&Lt; Formula 23 >

Li _a Ni _x Co _y M _z O _{2 - b a b}

Wherein M is at least one element selected from the group consisting of Mn, Mn, (V), Mg, Ga, Si, W, Mo, Fe, Cr, Cu, (Ti), aluminum (Al) and boron (B), and A is F, S, Cl, Br or a combination thereof. For example, 0.7? X <1, 0 <y? 0.3, 0 <z? 0.3; 0.8? X <1, 0 <y? 0.3, 0 <z? 0.3; 0.8? X <1, 0 <y? 0.2, 0 <z? 0.2; 0.83? X <0.97, 0 <y? 0.15, 0 <z? 0.15; Or 0.85? X <0.95, 0 <y? 0.1, 0 <z? 0.1.

For example, the lithium transition metal oxide may be a compound represented by the following Chemical Formulas 24 to 25:

&Lt; EMI ID =

LiNi _x Co _y Mn _z O ₂

&Lt; Formula 25 >

LiNi _x Co _y Al _z O ₂

In the above equations, 0.6? X? 0.95, 0 <y? 0.2, 0 <z? 0.1. For example, 0.7? X? 0.95, 0 <y? 0.3, and 0 <z? 0.3. For example, 0.8? X? 0.95, 0 <y? 0.3, 0 <z? 0.3. For example, 0.82? X? 0.95, 0 <y? 0.15, and 0 <z? 0.15. For example, 0.85? X? 0.95, 0 <y? 0.1, and 0 <z? 0.1.

For example, the lithium transition metal oxide LiNi _{0. 7} Co _{0 . 2} Mn _{0 . 1} O ₂ , LiNi _{0 . 88} Co _{0 . 08} Mn _{0 . 04} O ₂ , LiNi _0.8 Co _0.15 Mn _0.05 O ₂ , LiNi _{0 . 8} Co _{0 . 1} Mn _{0 . 1} O ₂ , LiNi _{0 . 88} Co _{0 . 1} Mn _{0 . 02} O ₂ , LiNi _{0 . 8} Co _{0 . 15} Al _{0 . 05} O ₂ , LiNi _0.8 Co _0.1 Mn _0.2 O ₂ or LiNi _{0 . 88} Co _{0 . 1} Al _{0 . 02} &lt; / _RTI &gt; _O2 .

The negative electrode active material may include at least one selected from the group consisting of a silicon compound, a carbon compound, a composite of a silicon compound and a carbon compound, and a silicon oxide (SiO _x , 0 <x <2). The carbon-based compound may be graphite or the like.

The composite of the silicon-based compound and the carbon-based material is a composite having a structure in which the silicon nanoparticles are disposed on the carbon-based compound, a composite in which the silicon particles are contained in the surface of the carbon-based compound and a silicon- Or may be a complex contained within the compound. The composite of the silicon-based compound and the carbon-based material can be obtained by dispersing silicon nanoparticles having an average particle diameter of about 200 nm or less on the carbon-based compound particles and then carbon coating the active material, silicon (Si) have. The secondary particle average particle diameter of the composite of the silicone compound and the carbon-based compound may be from 5 to 20 탆. The average particle diameter of the silicon nanoparticles may be 5 nm or more, 10 nm or more, 20 nm or more, 50 nm or more, or 70 nm or more. The average particle diameter of the silicon nanoparticles may be 200 nm or less, 150 nm or less, 100 nm or less, 50 nm or less, 20 nm or less, 10 nm or less. For example, the average particle diameter of the silicon nanoparticles may be 100 nm to 150 nm.

The secondary particle average particle diameter of the composite of the silicone compound and the carbon-based compound may be from 5 탆 to 18 탆, from 7 탆 to 18 탆, from 7 탆 to 15 탆, or from 10 탆 to 13 탆.

After the lithium battery has been charged and discharged at 25 DEG C for 300 cycles, the DCIR (direct current internal resistance) increase rate may be 155% or less, 150% or less, for example, 105 to 150%.

The energy density per unit volume of the lithium battery may be 500Wh / L or more, 550Wh / L or more, 600Wh / L or more, 650Wh / L or more, or 700Wh / L or more. A lithium battery can provide a high output by providing a high energy density of 500 Wh / L or more.

The shape of the lithium battery is not particularly limited, and includes a lithium ion battery, a lithium ion polymer battery, a lithium sulfur battery, and the like.

The lithium secondary battery according to one embodiment can be manufactured by the following method.

First, the anode is prepared.

For example, a cathode active material composition in which a cathode active material, a conductive agent, a binder and a solvent are mixed is prepared. The positive electrode active material composition is coated directly on the positive electrode collector to produce a positive electrode. Alternatively, the cathode active material composition may be cast on a separate support, and then a film peeled from the support may be laminated on the metal current collector to produce a cathode. The anode is not limited to those described above, but may be in a form other than the above.

The cathode active material may include a common lithium-containing metal oxide in addition to the nickel-rich lithium-nickel composite oxide described above. As the lithium-containing metal oxide, for example, two or more kinds of complex oxides of metal and lithium selected from cobalt, manganese, nickel, and combinations thereof may be used.

The cathode active material is, for example, Li _a A _{1 - b} B _b D ₂ (in the formula, 0.90 ≤ a ≤ 1.8, and 0 ≤ b ≤ 0.5); Li _a E _{1 - b} B _b O _{2 - c} D _{c where} 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05; LiE _{2 - b} B _b O _{4 - c} D _{c where} 0? B? 0.5, 0? C? 0.05; Li _a Ni _{1 -b- c} Co _b B _c D _? Wherein, in the formula, 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _{1 -b- c} Co _b B _c O _{2 - ?} F _? Wherein, in the formula, 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _{1 -b- c} Co _b B _c O _{2 - ?} F ₂ wherein 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _{1 -bc} Mn _b B _c D _? Wherein, in the formula, 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _{1 -b- c} Mn _b B _c O _{2 - ?} F _? Wherein, in the formula, 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _{1 -b- c} Mn _b B _c O _{2 - ?} F ₂ wherein 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, 0 <? Li _a Ni _b E _c G _d O ₂ wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, and 0.001 ≤ d ≤ 0.1; Li _a Ni _b Co _c Mn _d GeO ₂ wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, and 0.001 ≤ e ≤ 0.1; Li _a NiG _b O ₂ (in the above formula, 0.90? A? 1.8, and 0.001? B? 0.1); Li _a CoG _b O ₂ wherein, in the above formula, 0.90? A? 1.8, and 0.001? B? 0.1; Li _a MnG _b O ₂ (in the above formula, 0.90? A? 1.8, 0.001? B? 0.1); Li _a Mn ₂ G _b O ₄ wherein, in the above formula, 0.90? A? 1.8, and 0.001? B? 0.1; QO _2; QS ₂ ; LiQS ₂ ; V ₂ O ₅ ; LiV ₂ O ₅ ; LiIO ₂ ; LiNiVO _4; Li _(3-f) J ₂ (PO ₄ ) ₃ (0? F? 2); Li _(3-f) Fe ₂ (PO ₄ ) ₃ (0? F? 2); In the formula of LiFePO ₄ it may be a compound represented by any one:

In the above formula, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element or a combination thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; F is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or combinations thereof; Q is Ti, Mo, Mn, or a combination thereof; I is Cr, V, Fe, Sc, Y, or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

For example, LiCoO ₂ , LiMn _x O _2x (x = 1 or 2), LiNi _{1 - x} Mn _x O _2x (0 <x <1), LiNi _{1 -xy} Co _x Mn _y O ₂ 0.5, 0≤y≤0.5, a 1-xy> 0.5), LiFePO 4 or the like.

Of course, a compound having a coating layer on the surface of the compound may be used, or a compound having a coating layer may be mixed with the compound. The coating layer may comprise an oxide, a hydroxide of the coating element, an oxyhydroxide of the coating element, an oxycarbonate of the coating element, or a coating element compound of the hydroxycarbonate of the coating element. The compound constituting these coating layers may be amorphous or crystalline. The coating layer may contain Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr or a mixture thereof. The coating layer forming step may be any coating method as long as it can coat the above compound by a method that does not adversely affect physical properties of the cathode active material (for example, spray coating, dipping, etc.) by using these elements, It will be understood by those skilled in the art that a detailed description will be omitted.

The conductive agent is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, summer black; Conductive fibers such as carbon fiber and metal fiber; Carbon fluoride; Metal powders such as aluminum and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The content of the conductive agent is 1 to 20% by weight based on the total weight of the cathode active material composition.

The binder is a component that assists in binding of the active material and the conductive agent and bonding of the active material to the current collector, and is usually added in an amount of 1 to 30 wt% based on the total weight of the cathode active material composition. Examples of such binders include polyvinylidene fluoride (PVdF), polyvinylidene chloride, polybenzimidazole, polyimide, polyvinyl acetate, polyacrylonitrile, polyvinyl alcohol, carboxymethylcellulose (CMC) But are not limited to, starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, polyethylene, polypropylene, polystyrene, polymethylmethacrylate, polyaniline, acrylonitrile butadiene styrene, phenol resin, epoxy resin, polyethylene terephthalate , Polytetrafluoroethylene, polyphenylene sulfide, polyamideimide, polyetherimide, polyether sulfone, polyamide, polyacetal, polyphenylene oxide, polybutylene terephthalate, ethylene-propylene-diene terpolymer ), Sulfonated EPDM, styrene butadiene rubber (SBR), fluorine rubber, various copolymers and the like.

As the solvent, N-methylpyrrolidone, acetone, water or the like may be used, but not limited thereto, and any solvent which can be used in the technical field can be used. The content of the solvent is, for example, 10 to 100 parts by weight based on 100 parts by weight of the positive electrode active material. When the content of the solvent is within the above range, it is easy to form the active material layer.

The content of the positive electrode active material, the conductive agent, the binder and the solvent is a level commonly used in a lithium secondary battery. Depending on the application and configuration of the lithium secondary battery, one or more of the conductive agent, the binder, and the solvent may be omitted.

For example, N-methylpyrrolidone (NMP) may be used as a solvent, PVdF or PVdF copolymer may be used as a binder, and carbon black or acetylene black may be used as a conductive agent. For example, 94% by weight of the positive electrode active material, 3% by weight of the binder and 3% by weight of the conductive agent were mixed in powder form, NMP was added thereto so as to have a solid content of 70% by weight, The anode can be rolled.

The cathode current collector generally has a thickness of 3 mu m to 50 mu m. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical change in the battery, and may be formed of a material such as stainless steel, aluminum, nickel, titanium, sintered carbon, or a surface of aluminum or stainless steel Treated with carbon, nickel, titanium, silver or the like may be used. The current collector may have fine irregularities on the surface thereof to increase the adhesive force of the cathode active material, and various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric are possible.

The loading level of the prepared cathode active material composition is 30 mg / cm ² or more, for example, 35 mg / cm ² or more, specifically 40 mg / cm ² or more. The electrode density is 3 g / cc or more, for example, 3.5 g / cc or more. For energy density-intensive designs, a loading level of 35 mg / cm ² to 50 mg / cm ² or less and a density of 3.5 g / cc to 4.2 g / cc or less is preferred. For example, it may be a double-sided coated plate with a loading level of 37 mg / cc and a density of 3.6 g / cc.

When the loading level of the cathode active material and the range of the electrode density are satisfied, the battery including such a cathode active material can exhibit a high cell energy density of 500 wh / L or more. In the lithium secondary battery, the DCIR (direct current internal resistance) increase rate after charging and discharging at 45 ° C is 165% or less.

Next, the cathode is prepared.

For example, a negative electrode active material composition is prepared by mixing a negative electrode active material, a conductive agent, a binder and a solvent. The negative electrode active material composition is coated directly on the negative electrode collector and dried to produce a negative electrode. Alternatively, the negative electrode active material composition may be cast on a separate support, and then the film peeled off from the support may be laminated on the metal current collector to produce a negative electrode plate.

The negative electrode active material may be, for example, a silicon compound, a silicon oxide (SiO _x (0 <x <2), a composite of a silicon compound and a carbonaceous material. , For example from 10 to 150 nm. The term size refers to the average particle size when the silicone particles are spherical and to the average long axis length when the particles are non-spherical.

When the size of the silicon particles is within the above range, the life characteristics are excellent, and when the electrolyte according to one embodiment is used, the lifetime of the lithium secondary battery is further improved.

The carbon-based material may be crystalline carbon, amorphous carbon, or a mixture thereof. The crystalline carbon may be graphite such as natural graphite or artificial graphite in the form of amorphous, plate-like, flake, spherical or fibrous type, and the amorphous carbon may be soft carbon or hard carbon carbon, mesophase pitch carbide, calcined coke, and the like.

The composite of the silicon-based compound and the carbon-based material may be, for example, a composite having a structure in which silicon particles are disposed on the graphite surface, or a composite in which silicon particles are contained in and on the graphite surface. The composite may be prepared by dispersing Si particles having an average particle size of about 200 nm or less, for example, 100 to 200 nm, specifically 150 nm, on graphite particles, and then carbon-coating the active material or silicon (Si) The active material is present. Such a composite is available under the trade name SCN1 (Si particle on Graphite) or SCN2 (Si particle inside as well as on graphite). SCN1 is a carbon-coated active material obtained by dispersing Si particles having an average particle size of about 150 nm on graphite particles. And SCN2 is an active material in which Si particles having an average particle size of about 150 nm are present on and in the graphite.

The negative electrode active material may be used together with the negative electrode active material as long as it can be used as a negative electrode active material of a lithium secondary battery in the related art. (For example, Y is an alkali metal, an alkaline earth metal, a Group 13 to Group 16 element, a transition metal, a transition metal oxide rare earth element, or a mixture thereof) of Si, Sn, Al, Ge, Pb, Bi, Sb, And Y is an alkali metal, an alkaline earth metal, an element of group 13 to group 16, a transition metal, a rare earth element or a combination element thereof, and is not Sn), and the like. The element Y may be at least one element selected from the group consisting of Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Ge, P, As, Sb, Bi, Te, Po, or a combination thereof.

For example, the negative electrode active material may be lithium titanium oxide, vanadium oxide, lithium vanadium oxide, or the like.

The conductive agent and the binder in the negative electrode active material composition may be the same as those in the positive electrode active material composition.

However, in the negative electrode active material composition, water may be used as a solvent. For example, when water is used as a solvent, and carboxymethyl cellulose (CMC) - styrene butadiene rubber (SBR), acrylate polymer, or methacrylate polymer is used as a binder, and carbon black, acetylene black, You can use zero.

The content of the negative electrode active material, the conductive agent, the binder and the solvent is a level commonly used in a lithium secondary battery. Depending on the application and configuration of the lithium secondary battery, one or more of the conductive agent, the binder, and the solvent may be omitted.

For example, after mixing 94 wt% of the negative electrode active material, 3 wt% of the binder and 3 wt% of the conductive material in powder form, water is added so that the solid content is about 70 wt%, slurry is formed, , And rolled into a negative electrode plate.

The negative electrode current collector is generally made to have a thickness of 3 mu m to 50 mu m. Such an anode current collector is not particularly limited as long as it has conductivity without causing chemical change in the battery, and may be formed of a material such as copper, stainless steel, aluminum, nickel, titanium, fired carbon, surface of copper or stainless steel A surface treated with carbon, nickel, titanium, silver or the like, an aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

The loading level of the negative electrode active material composition is set according to the loading level of the positive electrode active material composition. Cm ² or more, for example, 15 mg / cm ² or more, depending on the capacity per g of the negative electrode active material composition. The electrode density can be 1.5 g / cc or more, for example, 1.6 g / cc or more. As a design that places importance on energy density, the density is preferably 1.65 g / cc or more and 1.9 g / cc or less.

When the loading level of the negative electrode active material and the range of the electrode density are satisfied, the battery including such an anode active material can exhibit a high cell energy density of 500 wh / L or more.

Next, a separation membrane to be inserted between the positive electrode and the negative electrode is prepared.

The separator is usable as long as it is commonly used in a lithium battery. A material having low resistance against the ion movement of the electrolyte and excellent in the ability to impregnate the electrolyte may be used. For example, selected from glass fiber, polyester, Teflon, polyethylene, polypropylene, polytetrafluoroethylene (PTFE), or a combination thereof, and may be nonwoven fabric or woven fabric. For example, a separable membrane such as polyethylene, polypropylene or the like can be used for the lithium ion battery, and a separator membrane having excellent electrolyte impregnation ability can be used for the lithium ion polymer battery. For example, the separation membrane can be produced according to the following method.

A polymer resin, a filler and a solvent are mixed to prepare a separator composition. The separation membrane composition may be directly coated on the electrode and dried to form a separation membrane. Alternatively, after the separation membrane composition is cast and dried on a support, a separation membrane film peeled from the support may be laminated on the electrode to form a separation membrane.

The polymer resin used in the production of the separator is not particularly limited, and any material used for the binder of the electrode plate may be used. For example, vinylidene fluoride / hexafluoropropylene copolymer, polyvinylidene fluoride (PVDF), polyacrylonitrile, polymethyl methacrylate or mixtures thereof may be used.

The loading level of the negative electrode active material composition is set according to the loading level of the positive electrode active material composition. Cm ² or more, for example, 15 mg / cm ² or more, depending on the capacity per g of the negative electrode active material composition. The electrode density can be 1.5 g / cc or more, for example, 1.6 g / cc or more. As a design that places importance on energy density, the density is preferably 1.65 g / cc or more and 1.9 g / cc or less.

Next, the above-described electrolyte is prepared.

According to one embodiment, the electrolyte may further include a non-aqueous electrolyte, a solid electrolyte, and an inorganic solid electrolyte in addition to the electrolyte described above.

Examples of the organic solid electrolyte include a polymer including a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, and an ionic dissociation group Can be used.

Examples of the inorganic solid electrolyte include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , Li ₂ SiS ₃ , Li ₄ SiO ₄ , Li ₄ SiO ₄ -LiI- such as _{LiOH, Li 3 PO 4 -Li 2} S-SiS 2 , may be used.

As shown in FIG. 1, the lithium secondary battery 1 includes an anode 3, a cathode 2, and a separator 4. The anode 3, the cathode 2 and the separator 4 are wound or folded and accommodated in the battery case 5. Then, the electrolyte is injected into the battery case 5 and sealed with a cap assembly 6 to complete the lithium secondary battery 1. The battery case may have a cylindrical shape, a rectangular shape, a thin film shape, or the like. For example, the lithium secondary battery may be a large-sized thin-film battery. The lithium secondary battery may be a lithium ion battery.

A separator may be disposed between the anode and the cathode to form a battery structure. The cell structure is laminated in a bi-cell structure, then impregnated with an electrolyte, and the obtained result is received in a pouch and sealed to complete a lithium ion polymer battery.

In addition, a plurality of battery assemblies may be stacked to form a battery pack, and such battery pack may be used for all devices requiring high capacity and high output. For example, a notebook, a smart phone, an electric vehicle, and the like.

The lithium secondary battery according to an embodiment of the present invention significantly reduces the rate of DCIR increase and exhibits excellent battery characteristics as compared with a lithium secondary battery employing a general nickel-rich lithium-nickel composite oxide as a cathode active material.

The operating voltage of the lithium secondary battery to which the positive electrode, the negative electrode and the electrolyte are applied is, for example, 2.5-2.8V as a lower limit and 4.1-4.4V as an upper limit, and an energy density is 500w / L or more.

Further, the lithium secondary battery may be a power tool, for example, powered by an electric motor and moving; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and the like; An electric motorcycle including an electric bike (E-bike) and an electric scooter (Escooter); An electric golf cart; And a power storage system, but the present invention is not limited thereto.

As used herein, alkyl refers to fully saturated branched or unbranched (or straight chain or linear) hydrocarbons.

Non-limiting examples of "alkyl" include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n- pentyl, 2,2-dimethylpentyl, 2,3-dimethylpentyl, n-heptyl and the like.

"Alkyl" at least one hydrogen atom of an alkyl group of a halogen atom, halogen-substituted C1-C20 (for _{example: CCF 3, CHCF 2, CH} 2 F, CCl 3 , etc.), an alkoxy of C1-C20 alkoxy, C2-C20 of A sulfamoyl group, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a C1-C20 alkyl group, a hydroxyl group, a nitro group, a cyano group, an amino group, an amidino group, a hydrazine, a hydrazone, a carboxyl group or a salt thereof, C20 alkenyl, C2-C20 alkynyl, C1-C20 heteroalkyl, C6-C20 aryl, C6-C20 arylalkyl, C6-C20 heteroaryl, C7-C20 heteroaryl An alkyl group, a C6-C20 heteroaryloxy group, a C6-C20 heteroaryloxyalkyl group or a C6-C20 heteroarylalkyl group.

The term " halogen " includes fluorine, bromine, chlorine, iodine and the like.

&Quot; Alkoxy " denotes " alkyl-O- ", wherein alkyl is as described above. Examples of the alkoxy group include a methoxy group, an ethoxy group, a 2-propoxy group, a butoxy group, a t-butoxy group, a pentyloxy group and a hexyloxy group. At least one hydrogen atom of the alkoxy may be substituted with the same substituent as the alkyl group described above.

&Quot; Alkenyl " refers to branched or unbranched hydrocarbons having at least one carbon-carbon double bond. Non-limiting examples of the alkenyl group include vinyl, allyl, butenyl, propenyl, isobutenyl, etc., and at least one hydrogen atom of the alkenyl may be substituted with the same substituent as the alkyl group described above.

&Quot; Alkynyl " refers to branched or unbranched hydrocarbons having at least one carbon-carbon triple bond. Non-limiting examples of the "alkynyl" include ethynyl, butynyl, isobutynyl, isopropynyl, and the like.

At least one hydrogen atom of " alkynyl " may be substituted with the same substituent as in the alkyl group described above. &Quot; Aryl " also includes groups wherein the aromatic ring is optionally fused to one or more carbon rings. Non-limiting examples of " aryl " include phenyl, naphthyl, tetrahydronaphthyl, and the like. Also, at least one hydrogen atom in the " aryl " group may be substituted with the same substituent as in the case of the above-mentioned alkyl group.

&Quot; Heteroaryl " means a monocyclic or bicyclic organic group containing one or more heteroatoms selected from N, O, P, or S and the remaining ring atoms carbon. The heteroaryl group may contain, for example, from 1 to 5 hetero atoms, and may include 5-10 ring members. The S or N may be oxidized to have various oxidation states.

Examples of heteroaryl include thienyl, furyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, , 5-oxadiazolyl, 1,3,4-oxadiazolyl group, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, Thiadiazolyl, isothiazol-3-yl, isothiazol-4-yl, isothiazol-5-yl, oxazol- Yl, isoxazol-3-yl, 1,2,4-triazol-5-yl, Yl, pyrid-3-yl, 2-pyrazin-4-yl, 1,2,3-triazol-5-yl, tetrazolyl, 2-yl, pyrazin-4-yl, pyrazin-5-yl, 2-pyrimidin-2-yl, 4-pyrimidin-2-yl or 5-pyrimidin-2-yl.

The term " heteroaryl " includes those where the heteroaromatic ring is optionally fused to one or more aryl, cycloaliphatic, or heterocycle.

The present invention will be described in more detail by way of the following examples and comparative examples. However, the examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

(Preparation of organic electrolytic solution)

Manufacturing example 1: 1.15  M LiPF ₆ , APS 1wt% (E1)

A nonaqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethylmethyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, 1.5 wt% of the compound to be displayed, 1 wt% of the compound represented by the following formula (9), and 1.15 M LiPF ₆ as the lithium salt were used to prepare an organic electrolytic solution.

&Lt; Formula 9 > <Formula 17a> <Formula 18a>

Comparative Manufacturing Example 1: 1.15  M LiPF ₆ , TMP 1wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example 1, except that trimethyl phosphate (1 wt%) was used instead of the compound (1 wt%).

compare Manufacturing example 2: 1.3  M LiPF ₆ , DVSF 1wt% , VC 0wt% (E4)

In a non-aqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40 1 wt% of the compound to be displayed was added, and 1.3 M LiPF ₆ was used as the lithium salt to prepare an organic electrolytic solution.

&Lt; Formula 10 > <Formula 17a>

Manufacturing example 2: 1.3  M LiPF ₆ , AMS 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Comparative Preparation Example 2 except that 1 wt% of a compound represented by the following formula (5) was used in place of the compound represented by the above formula (10).

&Lt; Formula 5 >

Manufacturing example 3: 1.3  M LiPF ₆ , MVS 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Comparative Preparation Example 2 except that 1 wt% of a compound represented by the following formula (3) was used instead of the compound represented by the above formula (10).

(3)

Manufacturing example 4: 1.3  M LiPF ₆ , EVS 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Comparative Preparation Example 2, except that 1 wt% of a compound represented by the following formula (4) was used instead of the compound represented by the above formula (10).

&Lt; Formula 4 >

Manufacturing example 5: 1.3  M LiPF ₆ , PVS 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Comparative Preparation Example 2, except that 1 wt% of a compound represented by the following formula (7) was used instead of the compound represented by the above formula (10).

&Lt; Formula 7 >

Comparative Manufacturing Example 3: 1.3  M LiPF ₆ , DVSF 0wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Comparative Preparation Example 2, except that the compound represented by Formula 10 was not added.

Manufacturing example 6: 1.0  M LiPF ₆ , APS 1wt% , VC 0wt% (E5)

A nonaqueous organic solvent in which a compound represented by the following general formula (17a), ethylene carbonate (EC), ethylmethyl carbonate (EMC) and dimethyl carbonate (DMC) were mixed at a volume ratio of 5:20:35:40, 1 wt% of a compound to be displayed was added, and 1.0 M LiPF ₆ was used as a lithium salt to prepare an organic electrolytic solution.

&Lt; Formula 9 > <Formula 17a>

Manufacturing example 7: 1.0  M LiPF ₆ , AMS 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example 6, except that 1 wt% of the compound represented by the following formula (5) was used instead of the compound represented by the above formula (9).

&Lt; Formula 5 >

Manufacturing example 8: 1.0  M LiPF ₆ , MVS 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example 6 except that 1 wt% of the compound represented by the following formula (3) was used instead of the compound represented by the above formula (9).

(3)

Manufacturing example 9: 1.0  M LiPF ₆ , EVS 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example 6 except that 1 wt% of a compound represented by the following formula (4) was used instead of the compound represented by the above formula (9).

&Lt; Formula 4 >

Manufacturing example 10: 1.0  M LiPF ₆ , PVS 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example 6 except that 1 wt% of the compound represented by the following formula (7) was used instead of the compound represented by the above formula (9).

&Lt; Formula 7 >

compare Manufacturing example 4: 1.0  M LiPF ₆ , DVSF 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example 6 except that 1 wt% of the compound represented by the following formula (10) was used instead of the compound represented by the above formula (9).

&Lt; Formula 10 >

(Manufacture of a Lithium Battery (full cell)

Example  1: Lithium secondary battery ( Full cell ), Cathode graphite ( Gr )

(Preparation of positive electrode)

As a cathode active material, LiNi _{0 . 88} Co _{0 . 08} Mn _{0 . 04} O ₂ 93.0% as a conductive material by weight of Denka black (Denka black) 4.0 wt% as a binder and a mixture of PVDF (Solef 6020, Solvay Co., Ltd.) 3.0% by weight, N- methyl-2-pyrrolidone (NMP) The mixture was poured into a solvent to have a solid content of 70% and dispersed for 30 minutes using a mechanical stirrer to prepare a cathode active material composition. The positive electrode active material composition was coated on both surfaces of an aluminum foil current collector having a thickness of 12 占 퐉 using a 3-roll coater so as to have a loading level of 37 mg / cm ² and dried in a hot air drier at 100 占 폚 Dried for 0.5 hours, dried once again under vacuum and at 120 ° C for 4 hours, and rolled to produce a positive electrode active material layer having a density of 3.6 g / cc on the current collector.

(Preparation of negative electrode)

97% by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) as a negative electrode active material, 1.5% by weight of styrene butadiene rubber (SBR) as a binder and 1.5% by weight of carboxymethyl cellulose (CMC) -2-pyrrolidone solvent so as to have a solid content of 70%, and then dispersed for 60 minutes using a mechanical stirrer to prepare an anode active material composition. The anode active material composition was coated on both sides of a copper foil current collector having a thickness of 10 占 퐉 using a 3-roll coater so as to have a loading level of 21.87 mg / cm &lt; ² &gt; Dried for 0.5 hours, dried again under vacuum at 120 ° C for 4 hours, and rolled to produce a negative electrode having a negative electrode active material layer having a density of 1.65 g / cc on the current collector.

(Assembly of Lithium Battery)

A 18650 cylindrical lithium battery was prepared using the prepared positive electrode, the negative electrode, and the polyethylene separator and the electrolyte prepared in Preparation Example 1 as the electrolyte.

Comparative Example  One

A lithium battery was prepared in the same manner as in Example 1 except that the organic electrolytic solution prepared in Comparative Preparation Example 1 was used in place of the organic electrolytic solution prepared in Preparation Example 1, respectively.

Comparative Example  2: Lithium secondary battery ( Full cell ), An anode carbon-silicon composite 2

A carbon-silicon composite (manufactured by BTR) in which carbon particles and silicon nanoparticles were mechanochemically complexed with 83.5 parts by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) instead of graphite powder as an anode active material And 12.5 parts by weight of the electrolyte prepared in Comparative Preparation Example 2 was used instead of the electrolyte prepared in Preparation Example 1 and the electrolyte prepared in Comparative Preparation Example 2 was used in place of the electrolyte prepared in Preparation Example 1. The average particle size of the Si nanoparticles was about 200 nm, and the average particle diameter of the carbon-silicon composite was about 5 μm.

Example  2 to 5

A lithium battery was prepared in the same manner as in Comparative Example 2, except that the organic electrolytes prepared in Preparation Examples 2 to 5 were used in place of the organic electrolytes prepared in Comparative Preparation Example 2, respectively.

Comparative Example  3

A lithium battery was prepared in the same manner as in Comparative Example 2, except that the organic electrolyte prepared in Comparative Preparation Example 3 was used in place of the organic electrolyte prepared in Comparative Preparation Example 2.

Example  6: Lithium secondary battery ( Full cell ), A negative electrode carbon-silicon composite 1

As a negative electrode active material, 83.5 parts by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) was mixed with carbon-silicon composite (manufactured by BTR) containing carbon coated silicon particles with a cost of 1300 mAh / 12.5 parts by weight, and the electrolyte solution prepared in Preparation Example 6 was used in place of the electrolyte solution prepared in Preparation Example 1, a lithium battery was prepared.

Example  7 to 10

A lithium battery was prepared in the same manner as in Example 6, except that the organic electrolytic solutions prepared in Preparation Examples 7 to 10 were used in place of the organic electrolytic solutions prepared in Preparation Example 6, respectively.

Comparative Example  4

A lithium battery was prepared in the same manner as in Example 6, except that the organic electrolytic solution prepared in Comparative Preparation Example 4 was used in place of the organic electrolytic solution prepared in Production Example 6.

Evaluation example  1: Evaluation of high temperature gas generation

The lithium batteries prepared in Examples 1 to 5 and Comparative Examples 1 and 3 were charged at a constant current of 4.3 V at a rate of 0.5 C in the first cycle at room temperature (25 캜) Was charged to constant voltage until it became 0.05C, and was discharged at a constant current of 2.8 V at a speed of 0.5C. The charging and discharging process was performed two more times to complete the conversion process.

The 2 ^nd cycle was charged to 4.3 V at a speed of 0.5 C, then charged at a constant voltage until the current became 0.05 C while maintaining the voltage at 4.3 V, and discharged at a rate of 0.2 C to a constant current of 2.8 V.

The 3 ^rd cycle was charged to 4.3 V at a speed of 0.5 C and then charged at a constant voltage until the current reached 0.05 C while maintaining the voltage at 4.3 V and discharged at a constant current of 2.80 V at a rate of 0.2C.

The battery was charged to 4.30 V at a rate of 0.5 C in the 4th cycle and then kept at 4.30 V until the current became 0.05 C. The charged battery was stored in a 60 ° C oven for 10 days, And discharged at a rate of 0.2 C up to 2.8 V, put in a jig, and after changing the internal gas pressure into a volume, the amount of generated gas was measured.

Some of the evaluation results are shown in Tables 1 and 2 below. The amount of gas generation is represented by a relative decrease relative to the gas generation amount of the comparative example.

Gas generation amount [ml / g] Gas reduction rate [%] Example 1 (1% APS) 0.47 24 Comparative Example 1 (TMP 1%) 0.62 0

As shown in Table 1, the lithium battery of Example 1 employing the organic electrolytic solution containing the sulfonic compound of the present invention is superior to the lithium battery of Comparative Example 1 employing the organic electrolyte containing the phosphate compound Respectively.

Gas generation amount [ml / g] Gas reduction rate [%] Example 2 (AMS 1%) 0.38 34 Example 3 (MVS 1%) 0.48 16 Example 4 (EVS 1%) 0.42 27 Example 5 (PVS 1%) 0.38 34 Comparative Example 3 (DVSF 0%) 0.57 0

As shown in Table 2, the lithium batteries of Examples 2 to 5 employing the organic electrolytic solution containing the sulfonic compound of the present invention are superior to the lithium battery of Comparative Example 3 employing the organic electrolytic solution containing no sulfonic compound The amount of gas generation was significantly reduced.

Evaluation example  2: room temperature (25 캜) Charging and discharging  Character rating

The lithium batteries manufactured in Examples 6 to 10 and Comparative Example 4 were charged at a constant current of 0.1 C rate at 25 DEG C until the voltage reached 4.3 V (vs. Li), and then 4.3 V was maintained in the constant voltage mode And cut off at a current of 0.05 C rate. Then, the discharge was performed at a constant current of 0.1 C rate until the voltage reached 2.8 V (vs. Li) during the discharge (Mars phase, 1 ^st cycle).

The lithium battery having passed through the 1 ^st cycle of the above-described conversion step was charged at a constant current of 0.2 C at a current of 25 C until the voltage reached 4.3 V (vs. Li), and then maintained at 4.3 C Lt; RTI ID = 0.0 &gt; of &lt; / RTI &gt; Subsequently, discharge was performed at a constant current of 0.2 C rate until the voltage reached 2.8 V (vs. Li) (Mars phase, 2nd cycle).

The lithium battery having undergone the above conversion step was charged at a constant current of 0.5 C at a current of 25 C until the voltage reached 4.3 V (vs. Li), and then maintained at 4.3 V in a constant voltage mode, (cut-off). Then, at the time of discharging, the battery was discharged at a constant current of 1.0 C rate until the voltage reached 2.8 V (vs. Li). This charge-discharge cycle was repeated 200 times.

A stopping time of 10 minutes was provided after one charge / discharge cycle in all of the above charge / discharge cycles.

Part of the charge-discharge test results are shown in Table 3 below. The capacity retention rate in the 200 ^th cycle is defined by the following equation (1).

&Quot; (1) &quot;

Capacity retention rate = [Discharge capacity in 200 ^th cycle / Discharge capacity in 1 ^st cycle] × 100

Graphite-silicon composite cathode Capacity retention rate [%] Example 6 (APS 1%) 82.6 Example 7 (AMS 1%) 83.1 Example 9 (EVS 1%) 83.0 Example 10 (PVS 1%) 83.8 Comparative Example 4 (DVSF 1%) 81.2

As shown in Table 3, the lithium batteries of Examples 6, 7, 9, and 10 employing the organic electrolytic solution containing the sulfonic compound represented by the formula (1) The life characteristic at room temperature was improved as compared with the lithium battery of Comparative Example 4 employing the organic electrolytic solution.

The energy density of the lithium battery produced in Example 6 was 710 Wh / L.

Evaluation example  3: Evaluation of DC resistance (DC-IR) at room temperature (25 ° C)

The initial DC resistance (DC-IR) of the lithium battery prepared in Comparative Example 2 and Examples 2 to 5 was measured at room temperature (25 占 폚) and before the high temperature storage in the 60 占 폚 oven of Evaluation Example 1, Was measured by the following method.

In the first cycle, the battery was charged to a voltage of 50% of a state of charge (SOC) at a current of 0.5 C, followed by cut-off at 0.02 C,

0.5 C for 30 seconds, then stopped for 30 seconds, charged at a constant current of 0.5 C for 30 seconds, allowed to stand for 10 minutes,

1.0 C for 30 seconds, then stopped for 30 seconds, charged at 0.5 C for 1 minute with a constant current, stopped for 10 minutes,

2.0 C for 30 seconds, then stopped for 30 seconds, charged at 0.5 C for 2 minutes with a constant current, stopped for 10 minutes,

3.0 C for 30 seconds, then 30 seconds of rest, then charged at 0.5 C for 3 minutes, and then stopped for 10 minutes.

The average voltage drop value for each C-rate for 30 seconds is the DC voltage value. The DC resistance at the measured DC voltage was calculated and is shown in Table 4 below.

Initial DC resistance
[mΩ] Comparative Example 2 (DVSF 1%) 252 Example 2 (AMS 1%) 162 Example 3 (MVS 1%) 160 Example 4 (EVS 1%) 161 Example 5 (PVS 1%) 170

As shown in Table 4, the lithium batteries of Examples 2 to 5 had lower initial DC resistance as compared with the lithium batteries of Comparative Example 2.

The lithium batteries of Examples 2 to 5 are superior in ion conductivity to the protective film formed on the surface of the negative electrode compared to the lithium battery of Comparative Example 2 and thus the cycle characteristics are improved by suppressing the generation of gas while suppressing the initial internal resistance .

The lithium batteries of Examples 2 to 5 significantly reduced the initial resistance as compared with the lithium battery of Comparative Example 2 and significantly improved the output power characteristics of the lithium battery, Lt; / RTI &gt;

The DC-IR increase rate is calculated by the following equation (2).

&Quot; (2) &quot;

DC-IR increase rate [%] = [DCIR in 200 ^th cycle / DCIR in 1 ^st cycle] × 100

Under the experimental conditions of Evaluation Example 2, the DC-IR of the lithium battery of Example 2 after charging and discharging at 25 ° C for 200 cycles was 150% of DC-IR in one cycle.

(Preparation of organic electrolytic solution)

Manufacturing example  A1: 1.15 M LiPF ₆ , APS 1wt% (E1)

A nonaqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethylmethyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, 1.5 wt% of the compound to be displayed, 1 wt% of the compound represented by the following formula (9), and 1.15 M LiPF ₆ as the lithium salt were used to prepare an organic electrolytic solution.

&Lt; Formula 9 > <Formula 17a> <Formula 18a>

Manufacturing example  A2: 1.15 M LiPF ₆ , AMS 1wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1, except that 1 wt% of a compound represented by the following formula (5) was used instead of 1 wt% of the compound represented by the above formula (9).

&Lt; Formula 5 >

Manufacturing example  A3: 1.15 M LiPF ₆ , PVS 1wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1 except that 1 wt% of the compound represented by the following formula (7) was used instead of 1 wt% of the compound represented by the above formula (9).

&Lt; Formula 7 >

compare Manufacturing example  A1: 1.15 M LiPF ₆ , APS 0wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1, except that the compound represented by Formula 9 was not added.

compare Manufacturing example  A2: 1.15 M LiPF ₆ , DVSF 1wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1, except that 1 wt% of a compound represented by the following formula (10) was used instead of 1 wt% of the compound represented by the above formula (9).

&Lt; Formula 10 >

compare Manufacturing example  A3: 1.15 M LiPF ₆ , DVSF 2wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1, except that 2wt% of the compound represented by Formula 10 was used instead of 1wt% of the compound represented by Formula 9 above.

compare Manufacturing example  A4: 1.15 M LiPF ₆ , DPS 1wt% (E1)

An organic electrolytic solution was prepared in the same manner as in Production Example A1, except that 1 wt% of the compound represented by Formula 11 was used instead of 1 wt% of the compound represented by Formula 9 above.

&Lt; Formula 11 >

Manufacturing example  A4: 1.0 M LiPF ₆ , APS 1wt% (E2)

A nonaqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethylmethyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, 1.5 wt% of the compound to be displayed, 1 wt% of the compound represented by the following formula (9) was added, and 1.0 M LiPF ₆ was used as the lithium salt to prepare an organic electrolytic solution.

&Lt; Formula 9 > <Formula 17a> <Formula 18a>

Manufacturing example  A5: 1.0 M LiPF ₆ , AMS 1wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that 1 wt% of a compound represented by the following formula (5) was used instead of the compound represented by the above formula (9).

&Lt; Formula 5 >

Manufacturing example  A6: 1.0 M LiPF ₆ , MVS 1wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that 1 wt% of the compound represented by the following formula (3) was used instead of the compound represented by the above formula (9).

(3)

Manufacturing example  A7: 1.0 M LiPF ₆ , EVS 1wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that 1 wt% of a compound represented by the following formula (4) was used instead of the compound represented by the above formula (9).

&Lt; Formula 4 >

Manufacturing example  A8: 1.0 M LiPF ₆ , PVS 1wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that 1 wt% of the compound represented by the following formula (7) was used instead of the compound represented by the above formula (9).

&Lt; Formula 7 >

compare Manufacturing example  A5: 1.0 M LiPF ₆ , DVSF 1wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that 1 wt% of a compound represented by the following formula (10) was used instead of 1 wt% of the compound represented by the above formula (9).

&Lt; Formula 10 >

compare Manufacturing example  A6: 1.0 M LiPF ₆ , APS 0wt% (E2)

An organic electrolytic solution was prepared in the same manner as in Production Example A4, except that the compound represented by Formula 9 was not added.

Manufacturing example  A9: 1.3 M LiPF ₆ , APS 1wt% (E3)

A nonaqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethylmethyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, An organic electrolytic solution was prepared by adding 1.5 wt% of the compound to be displayed and 1 wt% of the compound represented by the following formula (9) and using 1.3 M LiPF ₆ as the lithium salt.

&Lt; Formula 9 > <Formula 17a> <Formula 18a>

Manufacturing example  A10: 1.3 M LiPF ₆ , AMS 1wt% (E3)

An organic electrolytic solution was prepared in the same manner as in Production Example A9 except that 1 wt% of the compound represented by the following formula (5) was used in place of the compound represented by the above formula (9).

&Lt; Formula 5 >

Comparative Manufacturing Example  A7: 1.3 M LiPF ₆ , APS 0wt% (E3)

An organic electrolytic solution was prepared in the same manner as in Production Example A9, except that the compound represented by Formula 9 was not added.

compare Manufacturing example  A8: 1.3 M LiPF ₆ , DVSF 0.5 wt% (E3)

An organic electrolytic solution was prepared in the same manner as in Production Example A9, except that 0.5 wt% of the compound represented by Formula 10 was used instead of the compound represented by Formula 9 above.

Manufacturing example  A11: 1.3 M LiPF ₆ , EVS 1wt% , VC 0wt% (E4)

In a non-aqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, 1 wt% of the compound to be displayed was added, and 1.3 M LiPF ₆ was used as the lithium salt to prepare an organic electrolytic solution.

&Lt; Formula 4 > <Formula 17a>

Manufacturing example  A12: 1.3 M LiPF ₆ , APS 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Production Example A11 except that 1 wt% of the compound represented by the following formula (9) was used instead of the compound represented by the above formula (4).

&Lt; Formula 9 >

compare Manufacturing example  A9: 1.3 M LiPF ₆ , DVSF 1wt% , VC 0wt% (E4)

An organic electrolytic solution was prepared in the same manner as in Production Example A11, except that 1 wt% of the compound represented by Formula 10 was used instead of the compound represented by Formula 4 above.

Manufacturing example  A13: 1.0 M LiPF ₆ , EVS 1wt% , VC 0wt% (E5)

In a non-aqueous organic solvent obtained by mixing a compound represented by the following formula (17a), ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio of 5:20:35:40, 1 wt% of a compound to be displayed was added, and 1.0 M LiPF ₆ was used as a lithium salt to prepare an organic electrolytic solution.

&Lt; Formula 4 > <Formula 17a>

Manufacturing example  A14: 1.0 M LiPF ₆ , EVS 0.6 wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A13, except that the content of the compound represented by Formula 4 was changed to 0.6 wt%.

Manufacturing example  A15: 1.0 M LiPF ₆ , AMS 1wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A13 except that 1 wt% of the compound represented by the following formula (5) was used instead of the compound represented by the above formula (4).

&Lt; Formula 5 >

Manufacturing example  A16: 1.0 M LiPF ₆ , AMS 0.6 wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A15 except that the content of the compound represented by Formula 5 was changed to 0.6 wt%.

Manufacturing example  A17: 1.0 M LiPF ₆ , AMS 0.3 wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A15 except that the content of the compound represented by Formula 5 was changed to 0.3 wt%.

Manufacturing example  A18: 1.0 M LiPF ₆ , AMS 0.3 wt% + EVS 0.3 wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A15 except that the content of the compound represented by Chemical Formula 5 was changed to 0.3 wt% and 0.3 wt% of the compound represented by Chemical Formula 4 was added.

compare Manufacturing example  A10: 1.0 M LiPF ₆ , AMS 0wt% + EVS 0wt% , VC 0wt% (E5)

An organic electrolytic solution was prepared in the same manner as in Production Example A13, except that the compound represented by Formula 4 was not used.

(Manufacture of a Lithium Battery (full cell)

Example  A1: Lithium secondary battery ( Full cell ), The anode NCM ( Ni88 ) Negative electrode graphite ( Gr )

(Preparation of positive electrode)

As a cathode active material, LiNi _{0 . 88} Co _{0 . 08} Mn _{0 . 04} O ₂ 93.0% as a conductive material by weight of Denka black (Denka black) 4.0 wt% as a binder and a mixture of PVDF (Solef 6020, Solvay Co., Ltd.) 3.0% by weight, N- methyl-2-pyrrolidone (NMP) The mixture was poured into a solvent to have a solid content of 70% and dispersed for 30 minutes using a mechanical stirrer to prepare a cathode active material composition. The positive electrode active material composition was coated on both sides of an aluminum foil current collector having a thickness of 12 탆 using a 3-roll coater, dried in a hot air drier at 100 캜 for 0.5 hour, Dried again, and rolled to produce a positive electrode having a positive electrode active material layer on the current collector.

(Preparation of negative electrode)

97% by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) as a negative electrode active material, 1.5% by weight of styrene butadiene rubber (SBR) as a binder and 1.5% by weight of carboxymethyl cellulose (CMC) -2-pyrrolidone solvent so as to have a solid content of 70%, and then dispersed for 60 minutes using a mechanical stirrer to prepare an anode active material composition. The anode active material composition was coated on both sides of a copper foil current collector having a thickness of 10 占 퐉 using a 3-roll coater and dried in a hot-air drier at 100 占 폚 for 0.5 hour. Subsequently, And then rolled to produce a negative electrode having a negative electrode active material layer on the current collector.

(Assembly of Lithium Battery)

A 18650 cylindrical lithium battery was prepared using the prepared positive electrode, the negative electrode, and the polyethylene separator and the electrolyte prepared in Production Example A1 as the electrolyte. The capacity of the lithium battery was about 0.5 Ah and the current density (loading amount) was 4.4 mAh / cm ² .

Comparative Example  A1 to A4

Lithium batteries were prepared in the same manner as in Example A1 except that the organic electrolytes prepared in Comparative Preparations A 1 to A 4 were used in place of the organic electrolytes prepared in Production Example A1.

Example  A2: Lithium secondary battery ( Full cell ), The anode NCM ( Ni88 ) Negative electrode graphite ( Gr )

A lithium battery was produced in the same manner as in Example A1. The capacity of the lithium battery was about 0.5 Ah, but the current density (loading amount) was adjusted to be 3.4 mAh / cm ² .

Example  A3 to A4

Lithium batteries were prepared in the same manner as in Example A2 except that the organic electrolytes prepared in Production Examples A2 and A3 were used instead of the organic electrolytes prepared in Production Example A1.

Comparative Example  A5 to A7

Lithium batteries were prepared in the same manner as in Example A2 except that organic electrolytic solutions prepared in Comparative Preparation Examples A2, A1 and A4 were respectively used instead of the organic electrolytic solutions prepared in Production Example A1.

Example  A5: Lithium secondary battery ( Full cell ), The anode NCM ( Ni88 ) Negative carbon-silicon composite 1

As a negative electrode active material, 83.5 parts by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) was mixed with carbon-silicon composite (manufactured by BTR) containing carbon coated silicon particles with a cost of 1300 mAh / 12.5 parts by weight was used instead of the electrolytic solution prepared in Production Example A1, and the electrolytic solution prepared in Production Example A4 was used in place of the electrolytic solution prepared in Production Example A1. The capacity of the lithium battery was about 0.5 Ah and the current density (loading amount) was adjusted to be 3.4 mAh / cm ² .

Example  A6 to A9

A lithium battery was produced in the same manner as in Example A5 except that the organic electrolytic solution prepared in Production Examples A5 and A8 was used instead of the organic electrolytic solution prepared in Production Example A4.

Comparative Example  A8 to A9

A lithium battery was prepared in the same manner as in Example A5 except that the organic electrolytic solutions prepared in Comparative Preparation Examples A5 and A6 were respectively used instead of the organic electrolytic solutions prepared in Production Example A4.

Example  A10: Lithium secondary battery ( Full cell ), The anode NCA ( Ni88 ) Negative electrode graphite ( Gr )

As a cathode active material, LiNi _{0 . 88} Co _{0 . 08} Mn _{0 . 04} LiNi ₀ instead of O _{2 . 88} Co _{0 . 08} A1 _{0 . 04} O ₂ and that the electrolyte prepared in Production Example A9 was used in place of the electrolyte prepared in Production Example A1, a lithium battery was produced.

The capacity of the lithium battery was about 0.5 Ah and the current density (loading amount) was adjusted to be 3.4 mAh / cm ² .

Example  A11

A lithium battery was prepared in the same manner as in Example A10 except that the organic electrolyte prepared in Preparation Example A10 was used instead of the organic electrolyte prepared in Preparation Example A9.

Comparative Example  A10 to A11

A lithium battery was prepared in the same manner as in Example A10 except that the organic electrolytes prepared in Comparative Preparations A7 and A8 were used in place of the organic electrolytes prepared in Preparation Example A9.

Example  A12: Lithium secondary battery ( Full cell ), The anode NCA ( Ni92 ) Negative carbon-silicon composite 1

As a cathode active material, LiNi _{0 . 88} Co _{0 . 08} Mn _{0 . 04} LiNi ₀ instead of O _{2 . 92} Co _{0 . 04} A1 _{0 . 04} O ₂ and 83.5 parts by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) instead of graphite powder as a negative electrode active material, and carbon-coated silicon particles having a charge amount of 1300 mAh / (Manufactured by BTR) was used in place of the electrolyte prepared in Production Example A1, and the electrolyte solution prepared in Production Example A11 was used in place of the electrolyte solution prepared in Production Example A1, to prepare a lithium battery Respectively.

The capacity of the lithium battery was about 5.3 Ah and the current density (loading amount) was adjusted to 4.6 mAh / cm ² .

Example  A13

A lithium battery was prepared in the same manner as in Example A12, except that the organic electrolyte prepared in Preparation Example A12 was used in place of the organic electrolyte prepared in Preparation Example A11.

Comparative Example  A12

A lithium battery was prepared in the same manner as in Example A12, except that the organic electrolytic solution prepared in Comparative Preparation Example A9 was used in place of the organic electrolytic solution prepared in Production Example A11.

Example  A14: Lithium secondary battery ( Full cell ), The anode NCM ( Ni60 ) Negative electrode graphite ( Gr )

As a cathode active material, LiNi _{0 . 88} Co _{0 . 08} Mn _{0 .} Instead of ₀₄ O ₂ graphite powder, LiNi _{0 . 60} Co _{0 . 20} Mn _{0 . 20} O ₂ and that the electrolyte prepared in Production Example A13 was used in place of the electrolyte prepared in Production Example A1, a lithium battery was prepared.

The capacity of the lithium battery was about 4.1 Ah and the current density (loading amount) was adjusted to 4.5 mAh / cm ² .

Example  A15

A lithium battery was produced in the same manner as in Example A14, except that the organic electrolytic solution prepared in Production Example A15 was used in place of the organic electrolytic solution prepared in Production Example A13.

Comparative Example  A13

A lithium battery was prepared in the same manner as in Example A14, except that the organic electrolytic solution prepared in Comparative Preparation Example A10 was used instead of the organic electrolytic solution prepared in Production Example A13.

Example  A16: Lithium secondary battery ( Full cell ), The anode NCM ( Ni88 ) Negative carbon-silicon composite 1

As a negative electrode active material, 83.5 parts by weight of graphite powder (MC20, purity not less than 99.9%, manufactured by Mitsubishi Chemical) was mixed with carbon-silicon composite (manufactured by BTR) containing carbon coated silicon particles with a cost of 1300 mAh / 12.5 parts by weight was used instead of the electrolyte prepared in Preparation Example A1 and the electrolyte prepared in Preparation Example A13 was used in place of the electrolyte prepared in Preparation Example A1. However, a non-cylindrical stacked lithium battery was produced.

The capacity of the lithium battery was about 1 Ah and the current density (loading amount) was adjusted to 6.0 mAh / cm ² .

Example  A17 to A20

Lithium batteries were prepared in the same manner as in Example A16 except that the organic electrolytes prepared in Production Examples A14, A16, A17, and A18 were used in place of the organic electrolytes prepared in Production Example A13.

Comparative Example  A14

A lithium battery was prepared in the same manner as in Example A16, except that the organic electrolytic solution prepared in Comparative Preparation Example A10 was used in place of the organic electrolytic solution prepared in Production Example A13.

Evaluation example  A1: Evaluation of the amount of hot gas generated

The lithium batteries prepared in Examples A1 to A20 and Comparative Examples A1 to A11 were charged at a constant current of 4.3 V at a rate of 0.5 C in the first cycle at room temperature (25 캜) Was charged to constant voltage until it became 0.05C, and was discharged at a constant current of 2.8 V at a speed of 0.5C. The charging and discharging process was performed two more times to complete the conversion process.

The 2 ^nd cycle was charged to 4.3 V at a speed of 0.5 C, then charged at a constant voltage until the current became 0.05 C while maintaining the voltage at 4.3 V, and discharged at a rate of 0.2 C to a constant current of 2.8 V.

The 3 ^rd cycle was charged to 4.3 V at a speed of 0.5 C and then charged at a constant voltage until the current reached 0.05 C while maintaining the voltage at 4.3 V and discharged at a constant current of 2.80 V at a rate of 0.2C.

The battery was charged to 4.30 V at a rate of 0.5 C in the 4th cycle and then kept at 4.30 V until the current became 0.05 C. The charged battery was stored in a 60 ° C oven for 10 days, And discharging it to 2.8 V. After putting it in a jig, it was converted into the volume of the internal gas pressure, and the amount of generated gas was measured.

Some of the evaluation results are shown in Tables 6, 7, 9, and 11 below. The amount of gas generation is represented by a relative decrease relative to the gas generation amount of the comparative example.

Evaluation example  A2: room temperature (25 DEG C) Charging and discharging  Character rating

The lithium batteries prepared in Examples A1 to A20 and Comparative Examples A1 to A11 were charged at a constant current of 0.1 C rate at 25 DEG C until the voltage reached 4.3 V (vs. Li), and then 4.3 V in constant voltage mode And cut off at a current of 0.05 C rate. Then, the discharge was performed at a constant current of 0.1 C rate until the voltage reached 2.8 V (vs. Li) during the discharge (Mars phase, 1 ^st cycle).

The lithium battery having passed through the 1 ^st cycle of the above-described conversion step was charged at a constant current of 0.2 C at a current of 25 C until the voltage reached 4.3 V (vs. Li), and then maintained at 4.3 C Lt; RTI ID = 0.0 &gt; of &lt; / RTI &gt; Subsequently, discharge was performed at a constant current of 0.2 C rate until the voltage reached 2.8 V (vs. Li) (Mars phase, 2nd cycle).

The lithium battery having undergone the above conversion step was charged at a constant current of 0.5 C at a current of 25 C until the voltage reached 4.3 V (vs. Li), and then maintained at 4.3 V in a constant voltage mode, (cut-off). Then, at the time of discharging, the battery was discharged at a constant current of 1.0 C rate until the voltage reached 2.8 V (vs. Li). This charge-discharge cycle was repeated 200 times.

A stopping time of 10 minutes was provided after one charge / discharge cycle in all of the above charge / discharge cycles.

Some of the above charge / discharge test results are shown in Tables 5, 7, 9, 11 and 13. The capacity retention rate in the 200 ^th cycle is defined by the following equation (1).

&Quot; (1) &quot;

Capacity retention rate = [Discharge capacity in 200 ^th cycle / Discharge capacity in 1 ^st cycle] × 100

Evaluation example  A3: Normal temperature Charging and discharging  Evaluation of gas generation

The lithium batteries prepared in Examples A1 to A20 and Comparative Examples A1 to A11 were charged in a jig after completing evaluation of charging / discharging characteristics at the room temperature of Evaluation Example A2, and then the internal gas pressure change was converted into a volume, Respectively.

Some of the evaluation results are shown in Table 5 below. The amount of gas generation is represented by a relative decrease relative to the gas generation amount of the comparative example.

Evaluation example  A4: Initial DC resistance (DC-IR) evaluation at room temperature (25 ° C)

The lithium batteries prepared in Examples A1 to A20 and Comparative Examples A1 to A11 were subjected to initial DC resistance (DC-IR ) Was measured by the following method.

In the first cycle, the battery was charged to a voltage of 50% of a state of charge (SOC) at a current of 0.5 C, followed by cut-off at 0.02 C,

0.5 C for 30 seconds, then stopped for 30 seconds, charged at a constant current of 0.5 C for 30 seconds, allowed to stand for 10 minutes,

1.0 C for 30 seconds, then stopped for 30 seconds, charged at 0.5 C for 1 minute with a constant current, stopped for 10 minutes,

2.0 C for 30 seconds, then stopped for 30 seconds, charged at 0.5 C for 2 minutes with a constant current, stopped for 10 minutes,

3.0 C for 30 seconds, then 30 seconds of rest, then charged at 0.5 C for 3 minutes, and then stopped for 10 minutes.

The average voltage drop value for each C-rate for 30 seconds is the DC voltage value. The DC resistance at the measured DC voltage was calculated and some of the results are shown in Tables 5, 6, 8, 10, and 11 below.

Evaluation example 5: 60 ° C  High temperature stability evaluation (high temperature Capacity recovery rate  evaluation)

The lithium batteries prepared in Examples A14 to A15 and Comparative Example A10 were charged at a constant current of 4.3 V at a rate of 0.5 C in a 1st cycle at room temperature (25 캜) C, and discharged at a constant current of 2.8 V at a speed of 0.5C.

The 2 ^nd cycle was charged to 4.3 V at a speed of 0.5 C, then charged at a constant voltage until the current became 0.05 C while maintaining the voltage at 4.3 V, and discharged at a rate of 0.2 C to a constant current of 2.8 V.

The 3 ^rd cycle was charged to 4.3 V at a rate of 0.5 C, then charged at 4.3 V, constant-voltage charged until the current reached 0.05 C, and discharged to 2.8 V at a rate of 0.2 C. The discharge capacity in the 3 ^rd cycle was regarded as a standard capacity.

Charged to 4.30 V at a speed of 0.5 C in the fourth cycle, and then charged at a constant voltage until the current became 0.05 C while maintaining the voltage at 4.30 V. Then,

After the charged battery was stored in an oven at 60 ° C for 30 days, the battery was taken out and discharged at a rate of 0.1C to 2.80 V for a 4th cycle.

The charge / discharge evaluation results are shown in Table 12 below. The capacity retention rate after high temperature storage is defined by the following equation (3).

&Quot; (3) &quot;

Capacity recovery rate [%] = [discharging capacity after leaving at high temperature for 4th cycle / standard capacity] 占 100 (the standard capacity is discharging capacity at 3 ^rd cycle)

Ni88NCM / Gr / E1 Initial DC resistance [mΩ] Room temperature capacity maintenance rate [%] Gas reduction rate [%] after charge / discharge at room temperature Example A1 (1% APS) 188 92.9 50 Comparative Example A1 (APS 0%) 184 92.3 0 Comparative Example A2 (DVSF 1%) 204 91.1 70 Comparative Example A3 (DVSF 2%) 237 86.7 75 Comparative Example A4 (DPS 1%) 192 92.4 0

As shown in Table 5, the lithium battery of Example A1 employing the organic electrolytic solution containing the sulfonic compound of the present invention showed improved lifetime characteristics as compared with the lithium batteries of Comparative Examples A1 to A4.

The initial resistance of the lithium battery of Example A1 was lower than that of the lithium batteries of Comparative Examples A2 to A4, and was similar to that of Comparative Example A1.

The lithium battery of Example A1 significantly reduced the gas generation amount as compared with the lithium batteries of Comparative Examples A1 and A4.

When the initial resistance of the lithium battery is high, the output power characteristic of the lithium battery is significantly deteriorated, so that it is difficult to apply it to applications requiring high output such as an electric vehicle.

Ni88NCM / Gr / E1 Initial DC resistance [mΩ] Gas reduction rate after leaving at high temperature [%] Example A2 (1% APS) 133 28 Example A3 (AMS 1%) 128 33 Example A4 (PVS 1%) 130 23 Comparative Example A5 (DVSF 1%) 150 49 Comparative Example A6 (DVSF 0%) 120 0 Comparative Example A7 (DPS 1%) 125 0

As shown in Table 6, the lithium batteries of Examples A2 to A4 employing the organic electrolytic solution containing the sulfonic compound of the present invention had a remarkably reduced initial resistance as compared with the lithium battery of Comparative Example A5.

Compared with the lithium batteries of Comparative Examples A6 and A7, the lithium batteries of Examples A2 to A4 significantly decreased the gas generation amount.

Ni88NCM / Si + Gr / E2 Room temperature capacity maintenance rate [%] Gas reduction rate after leaving at high temperature [%] Example A5 (1% APS) 82.8 32 Example A6 (AMS 1%) 83.8 34 Example A8 (EVS 1%) 83.1 36 Example A9 (PVS 1%) 83.5 34 Comparative Example A8 (DVSF 1%) 81.1 45 Comparative Example A9 (DVSF 0%) 83.7 0

As shown in Table 7, the life characteristics of the lithium batteries of Examples A5, A6, A8 and A9 employing the organic electrolytic solution containing the sulfonic compound of the present invention were improved compared with those of the lithium battery of Comparative Example A8.

The lithium batteries of Examples A5, A6, A8 and A9 had significantly reduced gas generation as compared with the lithium batteries of Comparative Example A9.

Ni88NCM / Si + Gr / E2 Initial DC resistance [mΩ] Example A5 (1% APS) 143 Example A6 (AMS 1%) 138 Example A7 (MVS 1%) 142 Example A8 (EVS 1%) 132 Example A9 (PVS 1%) 152 Comparative Example A8 (DVSF 1%) 165

As shown in Table 8, the lithium batteries of Examples A5, A6, A8 and A9 employing the organic electrolytic solution containing the sulfonic compound of the present invention had a lower initial resistance than the lithium battery of Comparative Example A8.

When the initial resistance of the lithium battery is high, the output power characteristic of the lithium battery is significantly deteriorated, so that it is difficult to apply it to applications requiring high output such as an electric vehicle.

Ni88NCA / Gr / E3 Room temperature capacity maintenance rate [%] Gas reduction rate after leaving at high temperature [%] Example A11 (AMS 1%) 83.8 31 Comparative Example A10 (APS 0%) 81.0 0 Comparative Example A11 (DVSF 0.5%) 83.1 36

As shown in Table 9, the lithium battery of Example A11 employing the organic electrolytic solution containing the sulfonate compound of the present invention had improved life characteristics as compared with the lithium batteries of Comparative Examples A10 and A11.

The amount of gas generated in the lithium battery of Example A11 was significantly lower than that of the lithium battery of Comparative Example A10.

Ni88NCA / Gr / E3 Initial DC resistance [mΩ] Example A10 (1% APS) 147 Example A11 (AMS 1%) 144 Comparative Example A11 (DVSF 0.5%) 158

As shown in Table 10, the lithium batteries of Examples A10 to A11 employing the organic electrolytic solution containing the sulfonic compound of the present invention had a lower initial resistance than the lithium battery of Comparative Example A11.

When the initial resistance of the lithium battery is high, the output power characteristic of the lithium battery is significantly deteriorated, so that it is difficult to apply it to applications requiring high output such as an electric vehicle.

Ni88NCA / Si + Gr / E4 Initial DC resistance [mΩ] Room temperature capacity maintenance rate [%] Gas reduction rate after leaving at high temperature [%] Example A12 (1% APS) 36 88.2 40 Example A13 (AMS 1%) 36 88.3 32 Comparative Example A12 (DVSF 1%) 44 85.2 43

As shown in Table 11, the lithium batteries of Examples A12 to A13 employing the organic electrolytic solution containing the sulfonic compound of the present invention had a reduced initial resistance and improved life characteristics as compared with the lithium battery of Comparative Example A12.

The lithium batteries of Examples A12 to A13 were similar in gas generation amount to those of the lithium battery of Comparative Example A12.

Ni60NCM / Gr / E5 High temperature capacity recovery rate [%] Example A14 (EVS 1%) 95.2 Example A15 (AMS 1%) 95.3 Comparative Example A13 (EVS 0%) 91.0

As shown in Table 12, the lithium batteries of Examples A14 to A15 employing the organic electrolytic solution containing the sulfonic compound of the present invention improved the capacity recovery rate after storage at high temperature in comparison with the lithium battery of Comparative Example A13.

Ni88NCM / Si + Gr / E5 Room temperature capacity maintenance rate [%] Example A16 (EVS 1%) 92.8 Example A17 (EVS 0.6%) 93.4 Example A18 (AMS 0.6%) 93.5 Example A19 (AMS 0.3%) 93.5 Example A20 (AMS 0.3% + EVS 0.3%) 93.4 Comparative Example A14 (EVS 0%) 92.8

As shown in Table 13, the lithium batteries of Examples A16 to A20 employing the organic electrolytic solution containing the sulfonic compound of the present invention had improved life characteristics as compared with the lithium batteries of Comparative Example A14.

Claims (22)

A lithium battery electrolyte additive represented by the following formula (1):
&Lt; Formula 1 >

In this formula,
R ₁ is an alkyl group having 1 to 5 carbon atoms which is substituted or unsubstituted with halogen, a cycloalkyl group having 4 to 10 carbon atoms which is substituted or unsubstituted with halogen, or an aryl group having 5 to 10 carbon atoms which is substituted or unsubstituted with halogen, A substituted or unsubstituted heteroaryl group having 2 to 10 carbon atoms,
R ₂ is an alkenyl group having 2 to 10 carbon atoms which is substituted or unsubstituted with halogen. The lithium battery electrolyte additive of claim 1, wherein the sulfonic compound represented by Formula 1 is a sulfonic compound represented by Formula 2,
(2)

In this formula,
R ₃ is an alkyl group having 1 to 5 carbon atoms which is substituted or unsubstituted with halogen or an aryl group having 5 to 10 carbon atoms which is substituted or unsubstituted with halogen,
R ₄ is a covalent bond, an alkylene group having 1 to 5 carbon atoms, or an alkenylene group having 2 to 10 carbon atoms. The lithium battery electrolyte additive of claim 1, wherein the sulfone compound represented by Formula 1 is a compound represented by Formula 3 to 9:
&Lt; Formula 3 >< Formula 4 >

&Lt; Formula 5 >< EMI ID =

&Lt; Formula 7 &gt;&lt; EMI ID =

&Lt; Formula 9 >

Lithium salts; Organic solvent; And
An organic electrolytic solution comprising the additive according to any one of claims 1 to 3. The organic electrolytic solution according to claim 1, wherein the content of the sulfonic compound represented by Formula 1 is 0.1 wt% to 3 wt% based on the total weight of the organic electrolytic solution. The organic electrolytic solution according to claim 1, wherein the organic solvent comprises a cyclic carbonate compound represented by Formula 17:
&Lt; Formula 17 >

In this formula,
X ₁ and X ₂ are each independently hydrogen or halogen, and at least one of X ₁ and X ₂ is F; The organic electrolytic solution according to claim 6, wherein the content of the cyclic carbonate compound represented by the formula (17) is 10 vol% or less based on the total volume of the organic solvent. The organic electrolytic solution according to claim 1, wherein the organic electrolytic solution further comprises a cyclic carbonate compound represented by Formula 18:
&Lt; Formula 18 >

In this formula,
X ₃ and X ₄ are independently of each other hydrogen, halogen or an alkyl group having 1 to 3 carbon atoms. The organic electrolytic solution according to claim 8, wherein the content of the cyclic carbonate compound represented by the formula (18) is 2 wt% or less based on the total weight of the organic electrolytic solution. The method of claim 1, wherein the organic solvent is selected from the group consisting of ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate , Propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), ethyl propionate, ethyl butyrate, acetonitrile (AN), succinonitrile (SN), adiponitrile, dimethylsulfoxide, dimethyl An organic electrolytic solution containing at least one selected from the group consisting of formamide, dimethylacetamide, gamma-valerolactone, gamma-butyrolactone and tetrahydrofuran. The organic electrolytic solution according to claim 1, wherein the organic electrolytic solution contains 0.1 to 3.0% by weight of a sulfonic compound represented by the following general formulas (3) to (9) and 0.1 to 2.0% by weight of a compound represented by the following general formula 1 to 10 vol% of a compound represented by the following formula:
&Lt; Formula 3 >< Formula 4 >

&Lt; Formula 5 >< EMI ID =

&Lt; Formula 7 &gt;

&Lt; Formula 8 &gt;&lt; EMI ID =

&Lt; Formula 17a >< EMI ID =

The method of claim 1, wherein the lithium salt, _{LiPF 6, LiBF 4, LiCF 3} SO 3, Li (CF 3 SO 2) 2 N, LiC 2 F 5 SO 3, Li (FSO 2) 2 N, LiC 4 F 9 SO ₃ , LiN (SO ₂ CF ₂ CF ₃ ) ₂ , and compounds represented by the following formulas (19) to (22):
&Lt; Formula 19 >< EMI ID =

&Lt; Formula 21 &gt;&lt; EMI ID =

The organic electrolytic solution according to claim 1, wherein the concentration of the lithium salt is 0.01 to 5.0 M. A cathode comprising a cathode active material;
A negative electrode comprising a negative electrode active material; And
And an organic electrolyte disposed between the anode and the cathode,
Wherein the organic electrolytic solution comprises the additive according to any one of claims 1 to 3. The method according to claim 1,
Wherein the positive electrode active material comprises a lithium transition metal oxide containing nickel and at least one other transition metal, and the content of nickel is 80 mol% or more based on the total number of moles of the transition metal. The lithium battery according to claim 1, wherein the lithium transition metal oxide is represented by the following formula (23):
&Lt; Formula 23 >
Li _a Ni _x Co _y M _z O _{2 - b a b}
In the formula (23)
M is at least one element selected from the group consisting of manganese (Mn), vanadium (V), zirconium (Zr), and zirconium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn) Aluminum (Al) and boron (B), and A is F, S, Cl, Br or a combination thereof. The lithium secondary battery according to claim 1, wherein the lithium transition metal oxide is a compound represented by any of the following Chemical Formulas 24 to 25:
&Lt; EMI ID =
LiNi _x Co _y Mn _z O ₂
&Lt; Formula 25 &gt;
LiNi _x Co _y Al _z O ₂
In the above equations, 0.6? X? 0.95, 0 <y? 0.2, 0 <z? 0.1. The lithium battery according to claim 1, wherein the negative electrode active material comprises at least one selected from the group consisting of a silicon compound, a carbon compound, a composite of a silicon compound and a carbon compound, and silicon oxide (SiO _x , 0 <x <2). 19. The lithium battery according to claim 18, wherein the composite of the silicon compound and the carbon compound comprises carbon-coated silicon nanoparticles. The lithium battery according to claim 18, wherein the composite of the silicone compound and the carbon-based compound has an average particle diameter of 5 to 20 탆 and an average particle diameter of the silicon nanoparticle is 200 nm or less. The lithium battery according to claim 1, wherein a rate of increase in direct current internal resistance (DCIR) after charging and discharging at 200 DEG C at 25 DEG C is 150% or less. The lithium battery according to claim 1, wherein an energy density per unit cell volume is 500 Wh / L or more.

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