CN103151559A - Non-aqueous electrolyte solution for lithium ion battery and corresponding lithium ion battery - Google Patents

Abstract

The object of the present invention is to provide a high-performance non-aqueous electrolyte for lithium-ion batteries. Includes: lithium salts; organic solvents; and unsaturated phosphate compounds. The unsaturated phosphate compound helps to form a stable and dense passivation film (SEI) on the electrode surface, preventing further decomposition of solvent molecules. The electrolytic solution obtained according to the solution of the invention can improve the high-temperature storage performance and cycle performance of the battery.

Description

A kind of nonaqueous electrolytic solution for lithium ion battery and corresponding lithium ion battery thereof

technical field

The invention relates to the field of electrochemistry, in particular to the field of lithium ion secondary batteries.

Background technique

Portable electronic products such as cameras, digital video cameras, mobile phones, notebook computers, etc. are widely used in people's daily life. With the development of science and technology and market demand, higher requirements are put forward for the volume, weight, function and service life of portable electronic products. Therefore, it is an urgent need for the development of the industry to develop power supply products that are compatible with portable electronic products, especially to develop secondary batteries with high energy density, long life and high safety.

Compared with lead-acid batteries, nickel-cadmium batteries, and nickel-metal hydride batteries, lithium-ion batteries are widely used in portable electronic products because of their high energy density, high operating voltage, long life, and environmental protection.

Lithium-ion batteries are mainly composed of positive and negative electrodes, electrolyte and separator. The positive electrode is mainly a lithium-containing transition metal oxide, and the negative electrode is mainly a carbon material. Since the average discharge voltage of a Li-ion battery is approximately 3.6-3.7V, an electrolyte composition that is stable within a charge/discharge voltage of 0-4.2V is required. For this reason, lithium-ion batteries use a mixture of organic solvents in which lithium salts are dissolved as electrolytes. Preferred organic solvents should have high ionic conductivity, high dielectric constant and low viscosity. However, it is difficult for a single organic solvent to meet these requirements at the same time. Therefore, a mixture of an organic solvent with a high dielectric constant and a low-viscosity organic solvent is generally used as a solvent for the electrolyte of a lithium-ion battery. For example: Lithium-ion batteries usually use a mixture of cyclic carbonate solvents (such as ethylene carbonate) and linear carbonate solvents (such as dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate) as the solvent, lithium hexafluorophosphate as the solute of electrolyte.

During the first charging process of lithium-ion batteries, lithium ions are deintercalated from the lithium metal oxide of the cathode active material, migrate to the anode carbon electrode under the drive of voltage, and then intercalate into the carbon material. In this process, the electrolyte reacts with the surface of the carbon anode to produce Li ₂ CO ₃ , Li ₂ O, LiOH and other substances, thereby forming a passivation film on the surface of the carbon anode, which is called the solid electrolyte interface (SEI) film. Since lithium ions must pass through this SEI film regardless of charging or discharging, the performance of the SEI film determines many properties of the battery (such as cycle performance, high temperature performance, rate performance). After the formation of the SEI film for the first charge, it can prevent the further decomposition of the electrolyte solvent and form ion channels in the subsequent charge-discharge cycles. However, as charge and discharge proceed, the SEI film may rupture or gradually dissolve due to the repeated expansion and contraction of the electrode, and the exposed anode continues to react with the electrolyte while generating gas, thereby increasing the internal pressure of the battery and significantly reducing The cycle life of the battery. Especially when the battery is stored under high temperature conditions and subjected to charge and discharge cycles under high temperature conditions, the SEI film is more likely to be damaged, resulting in battery swelling and a significant decrease in cycle performance. According to the type of carbonate used in the electrolyte and the type of anode active material, the gas produced mainly includes CO, CO ₂ , CH ₄ , C ₂ H ₆ and so on.

Since the quality of the SEI film is crucial to the high-temperature storage performance and cycle performance of lithium-ion batteries, it is necessary to improve the quality of the SEI film through regulation to realize high-performance lithium-ion batteries. To solve this problem, people try to add a small amount of additives to the electrolyte to improve the SEI film in order to improve the performance of lithium-ion batteries. Researchers have worked hard to develop a series of film-forming additives such as vinylene carbonate (VC), vinyl ethylene carbonate (VEC), fluoroethylene carbonate (FEC), etc., which can form a more stable film on the surface of graphite negative electrode. SEI, thereby significantly improving the cycle performance of lithium-ion batteries. Japan Matsushita Electric Industry Co., Ltd.'s patent in China with application number 00801010.2 discloses a compound containing (R ^1a )P=(O)(OR ^2a )(OR ^3a ) (wherein, R _1a , R _2a , and R _3a represent independent carbon An electrolyte solution of an aliphatic hydrocarbon group with an atomic number of 7-12), which effectively controls the decrease in discharge capacity and the decrease in battery characteristics during high-temperature storage as the charge-discharge cycle progresses. Samsung SDI Co., Ltd. of South Korea discloses an electrolyte containing (R ₁ O)P=(OR ₂ )(CH=C(R ₃ )(R ₄ )) compound in Chinese application number 200410001479.7, which effectively prevents The battery bulges and improves the reliability of the battery.

However, the batteries in the above-mentioned patents are still not ideal in terms of high-temperature storage performance and cycle performance, and the decomposition of the electrolyte will still occur at higher temperatures, resulting in gas swelling, which will bring serious safety hazards. Therefore, it is necessary to develop new batteries. Additives to further improve the high-temperature storage performance of lithium-ion batteries.

Contents of the invention

The invention provides a non-aqueous electrolytic solution capable of suppressing battery swelling during high-temperature storage and improving cycle performance. The invention also provides a lithium ion battery using the non-aqueous electrolyte.

The invention provides a kind of non-aqueous electrolytic solution for lithium ion battery, comprising:

Lithium salt;

organic solvents; and

Unsaturated phosphoric acid ester compound, the phosphoric acid ester compound is shown in structural formula 1:

Wherein R ₁ , R ₂ , R ₃ are independently selected from hydrocarbon groups with 1-4 carbon atoms, and at least one of R ₁ , R ₂ , R ₃ is an unsaturated hydrocarbon group.

Preferably, the structure of the phosphate compound is shown in Structural Formula 2:

Wherein R ₄ is selected from a saturated hydrocarbon group or an unsaturated hydrocarbon group with 1-4 carbon atoms.

Preferably, the structure of the phosphate compound is shown in structural formula 3:

Wherein _R is selected from saturated or unsaturated hydrocarbon groups with 1-4 carbon atoms.

More preferably, the phosphate compound is selected from one of the following substances or a mixture thereof: trivinyl phosphate, triallyl phosphate.

Exemplary compounds among the compounds described in Structure 1 are also shown in Table 1, but are not limited thereto.

Table 1

The nonaqueous electrolytic solution for lithium ion batteries according to the present invention contains a phosphoric acid ester compound. The phosphate compound helps to form a stable and dense passivation film (SEI film) on the surface of the battery electrode, preventing further decomposition of solvent molecules. The electrolyte solution according to the solution of the present invention can improve the high-temperature storage performance and cycle performance of the battery.

According to the non-aqueous electrolyte solution for lithium ion batteries provided by the present invention, the content of the phosphoric acid ester compound described in structural formula 1 in the electrolyte solution is preferably 0.01%-2% based on the total weight of the electrolyte solution. When the content of phosphate compound in the electrolyte is not less than 0.01%, it is easier to form an effective SEI film on the surface of the battery electrode. More preferably, when the content of the phosphate compound in the electrolyte is not less than 0.1%, the stability of the SEI film can be further improved, thereby further improving the high-temperature storage performance and cycle performance of the battery. On the other hand, when the content of the phosphoric acid ester compound in the electrolyte is not higher than 2%, the increase in the internal resistance of the battery can be suppressed. More preferably, when the content of the phosphate compound in the electrolyte is not higher than 1%, the high-temperature storage and cycle performance of the battery can be further improved.

According to the non-aqueous electrolyte solution for lithium-ion batteries provided by the present invention, one of vinylene carbonate (VC), fluoroethylene carbonate (FEC), and vinyl ethylene carbonate (VEC) can be further added to the electrolyte. Or several additives to improve the cycle performance of the battery.

The solvent of the non-aqueous electrolyte for lithium-ion batteries of the present invention includes cyclic carbonates and chain carbonates, wherein the cyclic carbonates include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate One or more of esters (BC), and the chain carbonates include dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC ) in one or more.

The solute of the non-aqueous electrolyte solution for lithium ion battery of the present invention includes LiPF ₆ , LiBF ₄ , LiSbF ₆ , LiAsF ₆ , LiN(SO ₂ CF ₃ ) ₂ , LiN(SO ₂ C ₂ F ₅ ) ₂ , LiC( At least one of SO ₂ CF ₃ ) ₃ , LiN(SO ₂ F) ₂ . Of these, LiPF ₆ or its mixture with other lithium salts is preferred.

The non-aqueous electrolyte solution for lithium ion battery of the present invention is applied to a lithium ion battery having a negative electrode and a positive electrode, and the negative electrode is made of carbon materials, metal alloys, lithium-containing oxides, silicon-containing materials, and the like. Among them, the carbon material is preferably graphite or a carbon material obtained by coating the surface of graphite with amorphous carbon compared to graphite. The positive electrode material is preferably a lithium-containing transition metal oxide, such as one or more selected from the following materials: LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ , LiCo _{1-y My} O ₂ , LiNi _1-y My _{O 2} , LiMn _2-y My _{O 4} , _LiNix Co _y Mn _z M _1-xyz O ₂ , wherein M is selected from Fe, Co, Ni, Mn, Mg, Cu, Zn, Al, Sn, B One or more of , Ga, Cr, Sr, V, Ti, and 0≤y≤1, 0≤x≤1, 0≤z≤1, x+y+z≤1.

The present invention also provides a lithium ion battery, comprising: the non-aqueous electrolyte solution for lithium ion batteries provided by the present invention in the above content; a positive electrode capable of intercalating and deintercalating lithium; a negative electrode capable of intercalating and deintercalating lithium; Separator between positive and negative electrodes.

In addition, the present invention also provides the application of the above-mentioned phosphoric acid ester compound in improving the performance of the non-aqueous electrolyte solution for lithium-ion batteries and lithium-ion batteries.

Detailed ways

In order to describe in detail the technical content, structural features, achieved objectives and effects of the present invention, the following will be described in detail in conjunction with the embodiments.

Example 1

1) Preparation of electrolyte

Mix ethylene carbonate (EC), diethyl carbonate (DEC) and ethyl methyl carbonate (EMC) according to the mass ratio of EC:DEC:EMC=1:1:1, and then add lithium hexafluorophosphate (LiPF ₆ ) to mol The concentration is 1mol/L, then add 0.5% compound 1 according to the total mass of the electrolyte (compound 1, compound 2 referred to in the specific embodiment... refers to the compound of the corresponding number listed in table 1, below Phosphate compounds shown in each example).

2) Preparation of positive plate

Mix positive electrode active material lithium nickel cobalt manganese oxide LiNi _0.5 Co _0.2 Mn _0.3 O ₂ at a mass ratio of 93:4:3, conductive carbon black Super-P and binder polyvinylidene fluoride (PVDF), and then combine them Disperse in N-methyl-2-pyrrolidone (NMP) to obtain positive electrode slurry. The slurry is uniformly coated on both sides of the aluminum foil, dried, calendered and vacuum-dried, and an aluminum lead-out wire is welded on by an ultrasonic welder to obtain a positive plate with a thickness of 120-150 μm.

3) Preparation of negative plate

Mix negative active material modified natural graphite, conductive carbon black Super-P, binder styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC) at a mass ratio of 94:1:2.5:2.5, and then disperse them In deionized water, negative electrode slurry was obtained. The slurry is coated on both sides of the copper foil, dried, calendered and vacuum dried, and a nickel lead wire is welded with an ultrasonic welder to obtain a negative plate, the thickness of which is 120-150 μm.

4) Preparation of batteries

A polyethylene microporous membrane with a thickness of 20 μm is placed between the positive plate and the negative plate as a separator, and then the sandwich structure composed of the positive plate, negative plate and separator is wound, and then the wound body is flattened and put into a square aluminum In the metal shell, the lead wires of the positive and negative electrodes are respectively welded to the corresponding positions of the cover plate, and the cover plate and the metal shell are welded together with a laser welding machine to obtain the battery core to be injected.

5) Injection and formation of batteries

In a glove box with a dew point controlled below -40°C, inject the electrolyte solution prepared above into the cell through the liquid injection hole, and the amount of electrolyte should ensure that the gap in the cell is filled. Then carry out the formation according to the following steps: 0.05C constant current charge for 3 minutes, 0.2C constant current charge for 5 minutes, 0.5C constant current charge for 25 minutes, after shelving for 1 hour, it is shaped and sealed, and then further charged with a constant current of 0.2C to 4.2V, and left at room temperature After 24 hours, discharge to 3.0V with a constant current of 0.2C.

6) Normal temperature cycle performance test

Charge at room temperature with a constant current of 1C to 4.2V, then charge at a constant voltage until the current drops to 0.1C, and then discharge to 3.0V at a constant current of 1C, and cycle for 300 cycles, record the discharge capacity and the first cycle For the discharge capacity of 300 cycles, the capacity retention rate of normal temperature cycle is calculated according to the following formula:

Capacity retention rate = discharge capacity in the 300th week / discharge capacity in the first week * 100%

7) High temperature cycle performance test

Put the battery in an oven at a constant temperature of 45°C, charge it with a constant current of 1C to 4.2V, then charge it with a constant voltage until the current drops to 0.1C, and then discharge it with a constant current of 1C to 3.0V, and cycle it for 300 cycles, record For the discharge capacity of the first week and the discharge capacity of the 300th week, the capacity retention rate of the high temperature cycle is calculated according to the following formula:

Capacity retention rate = discharge capacity in the 300th week / discharge capacity in the first week * 100%

8) High temperature storage performance test

Charge at room temperature with a constant current of 1C to 4.2V, then charge at a constant voltage until the current drops to 0.1C, measure the thickness of the battery, and then store the battery in an oven with a constant temperature of 85°C for 4 hours. After taking it out, let the battery cool down to room temperature , measure the thickness of the battery, and calculate the thickness expansion rate of the battery according to the following formula:

Thickness expansion rate = (battery thickness after storage - battery thickness before storage) / battery thickness before storage * 100%

Example 2

Except that 0.5% of compound 1 was replaced by 0.5% of compound 2 in the preparation of the electrolyte, the others were the same as in Example 1. The data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 2.

Example 3

Except that 0.5% of compound 1 was replaced by 0.5% of compound 5 in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 2.

Example 4

Except that 0.5% of compound 1 was replaced by 0.5% of compound 7 in the preparation of the electrolyte, the others were the same as in Example 1. The data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 2.

Comparative example 1

Except that Compound 1 was not added in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 2.

Table 2

It can be seen from the data in Table 2 that, compared with the electrolyte without additives, the normal temperature cycle performance, high temperature cycle performance and high temperature storage performance of the battery prepared by adding the phosphate compound electrolyte are significantly improved.

Example 5

Except that 0.5% of compound 1 was replaced by 0.01% of compound 1 in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 3.

Example 6

Except that 0.5% of compound 1 was replaced by 0.1% of compound 1 in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 3.

Example 7

Except that 0.5% of compound 1 was replaced by 1% of compound 1 in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 3.

Example 8

Except that 0.5% of compound 1 was replaced by 2% of compound 1 in the preparation of the electrolyte, the others were the same as in Example 1, and the data obtained from the test of normal temperature cycle, high temperature cycle and high temperature storage are shown in Table 3.

table 3

It can be seen from the data in Table 3 that when the amount of compound 1 added in the electrolyte increases from 0.01% to 0.1%, the normal temperature cycle performance, high temperature cycle and high temperature storage performance of the battery gradually improve, but when the amount of compound 1 added exceeds 1% , the normal temperature cycle performance and high temperature cycle performance of the battery decreased, but it was still significantly better than the battery without compound 1.

Example 9

Except that in the preparation of the electrolyte, 0.5% of compound 1 was replaced by a combination of 1% vinylene carbonate (VC) and 0.5% of compound 1, the others were the same as in Example 1, and the obtained normal temperature cycle and high temperature cycle And the data of high temperature storage are shown in Table 4.

Example 10

Except that in the preparation of the electrolyte, 0.5% of compound 1 was replaced by a combination of 1% fluoroethylene carbonate (FEC) and 0.5% of compound 1, the others were the same as in Example 1, and the obtained normal temperature cycle, high temperature The data of circulation and high temperature storage are shown in Table 4.

Example 11

Except that in the preparation of the electrolyte, 0.5% of compound 1 was replaced by a combination of 1% vinyl ethylene carbonate (VEC) and 0.5% of compound 1, the others were the same as in Example 1, and the obtained normal temperature cycle, high temperature The data of circulation and high temperature storage are shown in Table 4.

Comparative example 2

Except that 0.5% of compound 1 was replaced by 1% of vinylene carbonate (VC) in the preparation of the electrolyte, the others were the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 4 .

Comparative example 3

Except that 0.5% of compound 1 was replaced by 1% of fluoroethylene carbonate (FEC) in the preparation of the electrolyte, the others were the same as in Example 1, and the data obtained from the test of normal temperature cycle, high temperature cycle and high temperature storage are shown in the table 4.

Comparative example 4

Except that 0.5% of compound 1 was replaced by 1% vinyl ethylene carbonate (VEC) in the preparation of the electrolyte, the others were the same as in Example 1, and the data obtained from the test of normal temperature cycle, high temperature cycle and high temperature storage are shown in the table 4.

Table 4

It can be seen from the data in Table 4 that on the basis of using VC, FEC or VEC, further adding compound 1 can make the battery obtain better high-temperature storage performance, and the normal-temperature cycle performance and high-temperature cycle performance are also improved.

Example 12

In addition to changing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ into LiNi _1/3 Co _1/3 Mn _1/3 O ₂ and in the preparation of the electrolyte, 0.5% of compound 1 was changed into 1% of vinylene carbonate ( VC) and 0.5% of compound 1, the others are the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

Example 13

In addition to replacing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ with LiNi _0.8 Co _0.15 Al _0.05 O ₂ and in the preparation of the electrolyte, 0.5% of compound 1 was replaced with 1% of vinylene carbonate (VC) and 0.5% of Except for the combination of Compound 1, the others are the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

Example 14

In addition to replacing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ with LiCoO ₂ and the preparation of the electrolyte, 0.5% of compound 1 was replaced by a combination of 1% vinylene carbonate (VC) and 0.5% of compound 1 , the others are the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

Example 15

In addition to replacing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ with LiMn ₂ O ₄ and the preparation of the electrolyte, 0.5% of compound 1 was replaced by a combination of 1% vinylene carbonate (VC) and 0.5% of compound 1 Other than that, the others are the same as in Example 1, and the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

Comparative Example 5

In addition to changing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ into LiNi _1/3 Co _1/3 Mn _1/3 O ₂ and in the preparation of the electrolyte, 0.5% of compound 1 was changed into 1% of vinylene carbonate ( VC), the others are the same as in Example 1, and the test data of normal temperature cycle, high temperature cycle and high temperature storage are shown in Table 5.

Comparative example 6

In addition to replacing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ with LiNi _0.8 Co _0.15 Al _0.05 O ₂ and replacing 0.5% of compound 1 with 1% of vinylene carbonate (VC) in the preparation of the electrolyte, other Same as in Example 1, the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

Comparative Example 7

Except that the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ was replaced by LiCoO ₂ and the preparation of the electrolyte was replaced by 0.5% of compound 1 with 1% of vinylene carbonate (VC), the others were the same as in Example 1, The normal temperature cycle, high temperature cycle and high temperature storage data obtained from the test are shown in Table 5.

Comparative Example 8

In addition to replacing the positive electrode material LiNi _0.5 Co _0.2 Mn _0.3 O ₂ with LiMn ₂ O ₄ and the preparation of the electrolyte, 0.5% of compound 1 was replaced with 1% of vinylene carbonate (VC), the others were the same as in Example 1 Similarly, the data of normal temperature cycle, high temperature cycle and high temperature storage obtained from the test are shown in Table 5.

table 5

It can be seen from the data in Table 5 that in lithium-ion batteries using LiNi _1/3 Co _1/3 Mn _1/3 O ₂ , LiNi _0.8 Co _0.15 Al _0.05 O ₂ , LiCoO ₂ , and LiMn ₂ O ₄ as positive electrode materials , adding compound 1 can also improve the high-temperature storage performance of the battery, and can also improve the normal-temperature cycle performance and high-temperature cycle performance of the battery.

The above is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process conversion made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, shall be The same reasoning is included in the patent protection scope of the present invention.

Claims (11)

1. lithium ion battery nonaqueous electrolytic solution comprises:

Lithium salts;

Organic solvent; And

Phosphate compound, this compound is as shown in structural formula 1:

R wherein ₁, R ₂, R ₃Independently be selected from respectively the alkyl that carbon number is 1-4, and R ₁, R ₂, R ₃In at least one is unsaturated alkyl.

2. lithium ion battery nonaqueous electrolytic solution according to claim 1, is characterized in that, described phosphate compound is as shown in structural formula 2:

R wherein ₄Be selected from saturated hydrocarbyl or unsaturated alkyl that carbon number is 1-4.

3. lithium ion battery nonaqueous electrolytic solution according to claim 1, is characterized in that, described phosphate compound is as shown in structural formula 3:

R wherein ₅Be selected from saturated hydrocarbyl or unsaturated alkyl that carbon number is 1-4.

4. lithium ion battery nonaqueous electrolytic solution according to claim 1, is characterized in that, described phosphate compound is selected from one of following material or its mixture: tricresyl phosphate vinyl acetate, TAP.

5. the described lithium ion battery nonaqueous electrolytic solution of according to claim 1 to 4 any one, is characterized in that, the content of described phosphate compound is counted 0.01%-2% by the total weight of electrolyte.

6. the described lithium ion battery nonaqueous electrolytic solution of according to claim 1 to 5 any one, it is characterized in that, described lithium ion battery also contains one or more in following material with nonaqueous electrolytic solution: vinylene carbonate, fluorinated ethylene carbonate, vinyl ethylene carbonate.

7. the described lithium ion battery nonaqueous electrolytic solution of according to claim 1 to 6 any one, is characterized in that, described organic solvent is the mixture of cyclic carbonate and linear carbonate.

8. lithium ion battery nonaqueous electrolytic solution according to claim 7, is characterized in that, described cyclic carbonate comprises: one or more in ethylene carbonate, propene carbonate, butylene.

9. lithium ion battery nonaqueous electrolytic solution according to claim 7, is characterized in that, described linear carbonate comprises: one or more in dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate.

10. according to claim 1 ~ 9 described lithium ion battery nonaqueous electrolytic solutions of any one, is characterized in that, described lithium salts is selected from: LiPF ₆, LiBF ₄, LiSbF ₆, LiAsF ₆, LiN (SO ₂CF ₃) ₂, LiN (SO ₂C ₂F ₅) ₂, LiC (SO ₂CF ₃) ₃, LiN (SO ₂F) ₂In at least a.

11. a lithium ion battery comprises:

The described lithium ion battery nonaqueous electrolytic solution of claim 1 ~ 10 any one;

Can embed the positive pole with removal lithium embedded;

Can embed the negative pole with removal lithium embedded; And

Be placed in the barrier film between positive pole and negative pole.