5-nitro isosorbide derivative, preparation method thereof and application of 5-nitro isosorbide derivative in battery

Abstract

The invention provides a 5-nitro isosorbide derivative, a preparation method thereof and an application of the 5-nitro isosorbide derivative in a battery. The 5-nitro isosorbide derivative is a compound 1, a compound 2 or a compound 3. The preparation method of the 5-nitro isosorbide derivative comprises the following steps: carrying out electrophilic addition reaction on 5-mononitro isosorbide ester and a first reagent in the presence of a certain solvent and an acid-binding agent to obtain a primary product, or carrying out acylation reaction on the 5-mononitro isosorbide ester and a second reagent in the presence of a certain solvent and an acid-binding agent to obtain a primary product; and purifying and drying the primary product. The 5-nitroisosorbide derivative can be used as an additive of a lithium ion battery, can form a good protective film on an interface of positive and negative electrode materials, has relatively small internal resistance, and can improve the low temperature and rate performance of the battery. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the technical field of material synthesis, and in particular to a compound used in a battery, and more particularly to a 5-nitroisosorbide derivative and a preparation method thereof, and application thereof in a battery. Background Art

[0002] 5-Nitroisosorbide derivatives refer to a series of compounds derived from the 5-nitroisosorbide group. At present, 5-nitroisosorbide derivatives are mainly used as nitric oxide donors and have been widely used in the treatment of cardiovascular diseases in clinic. As nitric oxide donors, 5-nitroisosorbide derivatives can quickly release high concentrations of nitric oxide under physiological conditions and exert the physiological effects of nitric oxide.

[0003] The current 5-nitroisosorbide derivatives are mainly based on 5-nitroisosorbide combined with some drug active ingredient groups. They can release some drug active agents and nitric oxide donor drug 5-mononitroisosorbate under the stimulation of high concentration of reactive oxygen in the inflammatory site. While delivering nitric oxide, it can also clear the high concentration of reactive oxygen in the inflammatory site, thus realizing the multifunctionality of nitric oxide donors.

[0004] Therefore, the current substances are targeted and are not applicable to other technical fields. In order to expand the application fields of 5-nitroisosorbide derivatives, the derivative groups of 5-nitroisosorbide derivatives can be improved to seek more 5-nitroisosorbide derivatives that can be applied to other technical fields. Summary of the invention

[0005] Based on the above problems, the purpose of the present invention is to provide a new 5-nitroisosorbide derivative and a preparation method thereof. The 5-nitroisosorbide derivative can be used in lithium-ion batteries to form a good protective film at the interface of positive and negative electrode materials, and at the same time has a small internal resistance, which can improve the low temperature and rate performance of the battery.

[0006] To achieve the above objectives, the first aspect of the present invention provides a 5-nitroisosorbide derivative, which is Compound 1, Compound 2 or Compound 3.

[0007]

[0008] Compound 1, Compound 2 or Compound 3 in the 5-nitroisosorbide derivatives of the present invention is a novel 5-nitroisosorbide derivative, which has a smaller molecule and can form a good nitride protective film with lower solubility at the interface of the positive and negative electrode materials, has lower interface impedance, and can be used in the electrolyte to improve the low temperature and rate performance of the battery.

[0009] The second aspect of the present invention provides a method for preparing 5-nitroisosorbide derivatives, comprising the steps of:

[0010] (1) subjecting 5-mononitroisosorbide to an electrophilic addition reaction with a first reagent in a certain solvent and an acid-binding agent to obtain a primary product, or subjecting 5-mononitroisosorbide to an acylation reaction with a second reagent in a certain solvent and an acid-binding agent to obtain a primary product;

[0011] (2) Purifying and drying the primary product.

[0012] The preparation method of the present invention is simple, and the preparation method can be prepared by using 5-mononitroisosorbide ester and a first reagent to undergo an electrophilic addition reaction under the catalysis of an acid-binding agent, or by using 5-mononitroisosorbide ester and a second reagent to undergo an acylation reaction under the catalysis of an acid-binding agent. The prepared 5-nitroisosorbide derivative can improve the low temperature and rate performance of the battery.

[0013] As a technical solution of the present invention, the first reagent is acrylonitrile, and the second reagent is a compound shown in structural formula 1, wherein R is CF3 or OCH3, R` is OH, OCOR or OR``, and R`` is a C1~C3 alkyl group.

[0014] As a technical solution of the present invention, the solvent includes at least one of water, dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, ether, benzene, toluene, acetonitrile, ether, cyclohexane, petroleum ether, tetrahydrofuran, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate and propylene carbonate.

[0015] As a technical solution of the present invention, the acid binding agent includes at least one of triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, sodium hydroxide, potassium hydroxide, potassium carbonate and cesium carbonate.

[0016] As a technical solution of the present invention, the molar ratio of the 5-mononitroisosorbide ester to the first reagent is 1:1-6, the molar ratio of the 5-mononitroisosorbide ester to the second reagent is 1:1-6, and the molar ratio of the acid binding agent to the 5-mononitroisosorbide ester is 1:0.5-6.0.

[0017] As a technical solution of the present invention, the reaction temperature of the addition reaction is 10-40°C, the reaction time of the addition reaction is 1-10h, the reaction temperature of the acylation reaction is 10-100°C, and the reaction time of the acylation reaction is 1-10h.

[0018] As a technical solution of the present invention, the purification method is washing, filtering or recrystallization.

[0019] The third aspect of the present invention provides the use of 5-nitroisosorbide derivatives in batteries.

[0020] The fourth aspect of the present invention provides an electrolyte solution, comprising a non-aqueous organic solvent, an electrolyte salt and an additive, wherein the additive comprises the aforementioned 5-nitroisosorbide derivatives, and the 5-nitroisosorbide derivatives account for 0.1 to 2.0% of the mass of the electrolyte solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the mass spectrum (hydrogen spectrum) of the product of Example 1.

[0022] Figure 2 This is the mass spectrum (hydrogen spectrum) of the product of Example 3.

[0023] Figure 3 This is the mass spectrum (fluorine spectrum) of the product of Example 3.

[0024] Figure 4 This is the mass spectrum (hydrogen spectrum) of the product of Example 5.

[0025] Figure 5 This is the mass spectrum (carbon spectrum) of the product of Example 5. DETAILED DESCRIPTION

[0026] The 5-nitroisosorbide derivatives of the present invention can be used in material synthesis, pharmaceutical intermediates, and batteries. In particular, the 5-nitroisosorbide derivatives are used in secondary batteries such as lithium ion batteries or sodium ion batteries. The 5-nitroisosorbide derivatives can be used as electrolyte additives to improve the low temperature and rate performance of the secondary battery.

[0027] Secondary batteries include positive electrode active materials, negative electrode active materials and electrolytes. If used in lithium-ion batteries, the positive electrode active materials may be layered transition metal lithium oxides or olivine-type lithium compounds. Layered transition metal lithium oxides may be, but are not limited to, lithium cobalt oxides (such as LiCoO2), lithium nickel oxides (such as LiNiO2), lithium manganese oxides (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides (chemical formula LiNi x Co y Mn (1-x-y) M zO2, where 0.6 ≤ x < 0.9, x + y < 1, 0 ≤ z < 0.08, and M is at least one of Al, Mg, Zr, and Ti), as well as coatings and dopants of the above materials. The olivine-type lithium compound is a lithium-containing phosphate with an olivine structure, and can be, but is not limited to, lithium iron phosphate, lithium manganese phosphate, lithium manganese iron phosphate, as well as coatings and dopants of the above materials. These positive electrode active materials can be used alone or in combination of two or more. If the secondary battery is a sodium-ion battery, the positive electrode active material can be a layered oxide, and the chemical formula of the layered oxide is Na x M (1-y-z) Fe y Mn z O2, where M includes at least one of Co, Ni, Cu, Mg, Zn, Al, Sn, Ga, Cr, Sr, V, and Ti, 0 < x ≤ 1, 0 ≤ y < 1, 0 ≤ z < 1, and y + z ≤ 1. Of course, the positive electrode material can also be other materials that can undergo ion deintercalation with sodium ions.

[0028] The negative electrode active material includes at least one of carbon-based materials, silicon-based materials, and tin-based materials. Among them, the carbon-based materials can be, but are not limited to, at least one of artificial graphite, natural graphite, hard carbon, soft carbon, graphene, and mesocarbon microbeads. The silicon-based materials can be, but are not limited to, at least one of silicon单质, silicon-oxygen composite materials, silicon-carbon composite materials, and silicon alloy materials. The tin-based materials can include tin单质, tin-carbon composite materials, tin-oxygen composite materials, and tin alloy compounds.

[0029] The electrolyte includes an electrolyte salt, a non-aqueous organic solvent, and an additive.

[0030] It should be noted that in the above translation, "硅单质" is directly translated as "silicon单质" as the original text seems to use "单质" in a non-standard way. It might be more appropriate to use "elemental silicon" in a more standard translation context. Also, "锡单质" is translated as "tin单质" for the same reason.If the secondary battery is a lithium ion battery, the electrolyte salt is a lithium salt. Further, the electrolyte salt may be, but is not limited to, at least one of lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethylsulfonyl)imide (LiTFSI), lithium methanesulfonate (LiCH3SO3), lithium trifluoromethylsulfonate (LiCF3SO3), lithium bis(oxalatoborate) (C4BLiO8), lithium difluorooxalatoborate (C2BF2LiO4), lithium difluorophosphate (LiPO2F2) and lithium difluorobis(oxalatophosphate) (LiDFBP). If the secondary battery is a sodium ion battery, the electrolyte salt is a sodium salt. Furthermore, the electrolyte salt may be, but is not limited to, at least one of NaPF6, NaBF4, NaClO4, NaBOB (sodium dioxalatoborate), NaODFB (sodium oxalatodifluoroborate), NaAsF6, NaSbF6, NaCF3SO3, NaN(SO2CF3)2, NaN(SO2C2F5)2, NaN(SO2C4F9)2, NaC(SO2CF3)3, NaPF2(C2O4)2, NaPF4(C2O4), NaB(CF3)4 and NaBF3(C2F5).

[0031] The non-aqueous organic solvent is selected from carbonate and / or carboxylic acid ester. Further, the non-aqueous organic solvent is selected from at least one of ethylene carbonate (PC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), γ-butyrolactone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl propionate, propyl propionate and butyl propionate.

[0032] The additive is a 5-nitroisosorbide derivative. Further, the additive is compound 1, compound 2 or compound 3. The 5-nitroisosorbide derivative accounts for 0.1 to 2.0% of the mass of the electrolyte. As an example, the proportion of 5-nitroisosorbide derivatives can be but is not limited to 0.1%, 0.3%, 0.5%, 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, 1.8%, and 2.0%.

[0033]

[0034] The preparation method of 5-nitroisosorbide derivatives comprises the steps of:

[0035] (1) subjecting 5-mononitroisosorbide to an electrophilic addition reaction with a first reagent in a certain solvent and an acid-binding agent to obtain a primary product, or subjecting 5-mononitroisosorbide to an acylation reaction with a second reagent in a certain solvent and an acid-binding agent to obtain a primary product;

[0036] (2) Purify and dry the primary product.

[0037] The first reagent is acrylonitrile, the second reagent is a compound shown in structural formula 1, wherein R is CF3 or OCH3, R` is OH, OCOR or OR``, and R`` is a C1-C3 alkyl group.

[0038]

[0039] If compound 1 is prepared, in step (1), 5-mononitroisosorbide and acrylonitrile undergo an electrophilic addition reaction, and the reaction formula is as follows.

[0040]

[0041] If compound 2 or 3 is prepared, in step (1), 5-mononitroisosorbide and the compound shown in structural formula 1 are subjected to acylation reaction, and the reaction formula is as follows.

[0042]

[0043] In step (1), the solvent includes at least one of water, dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, ether, benzene, toluene, acetonitrile, ether, cyclohexane, petroleum ether, tetrahydrofuran, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate and propylene carbonate. The acid binding agent includes at least one of triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, sodium hydroxide, potassium hydroxide, potassium carbonate and cesium carbonate. The molar ratio of 5-mononitroisosorbide to the first agent is 1:1-6. As an example, the molar ratio of the two can be, but not limited to, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6. The molar ratio of 5-mononitroisosorbide to the second agent is 1:1-6. As an example, the molar ratio of the two can be, but not limited to, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6. The molar ratio of the acid-binding agent to 5-mononitroisosorbide is 1:0.5-6.0. As an example, the molar ratio of the two can be, but not limited to, 1:0.5, 1:1.0, 1:1.5, 1:2.0, 1:2.5, 1:3.0, 1:3.5, 1:4.0, 1:4.5, 1:5.0, 1:5.5, 1:6.0. The reaction temperature of the addition reaction is 10-40°C. As an example, the reaction temperature can be, but not limited to, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, and 40°C. The reaction time of the addition reaction is 1-10h. As an example, the reaction time can be, but not limited to, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, and 10h. The reaction temperature of the acylation reaction is 10-100°C. As an example, the reaction temperature can be, but not limited to, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, and 100°C. The reaction time of the acylation reaction is 1-10h. As an example, the reaction time can be, but not limited to, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, and 10h.

[0044] In step (2), the purification method is washing, filtering or recrystallization. Among them, washing can be carried out by using hydrochloric acid aqueous solution, saturated salt water or water and washing multiple times. Filtration can be carried out by centrifugal stratification, vacuum filtration or ordinary filtration. Recrystallization can be carried out by using a mixed solvent of ethanol / water, and drying can be carried out by using anhydrous sodium sulfate.

[0045] In order to better illustrate the purpose, technical scheme and beneficial effects of the present invention, the present invention will be further described below in conjunction with specific embodiments. It should be noted that the following implementation method is a further explanation of the present invention and should not be used as a limitation of the present invention.

[0046] Part I: Preparation of 5-nitroisosorbide derivatives

[0047] Example 1

[0048] This embodiment is for preparing compound 1, and its preparation method includes the following steps.

[0049] (1) In a 500 ml three-necked flask, add 4.6 g of sodium hydroxide, add 200 ml of water to dissolve, place in an ice bath and cool to 0-5°C, add 20 g of 5-mononitroisosorbide, stir for 30 min, then slowly add 9.2 ml of acrylonitrile dropwise, remove the ice bath after the addition is complete, react at room temperature for 3 h, and after the reaction is completed, stand and separate to obtain an oily crude product in the lower layer.

[0050] (2) The lower layer of crude oily product was diluted with dichloromethane, washed with saturated brine and water in turn, and the organic phases were combined and dried over anhydrous sodium sulfate to remove dichloromethane to obtain 21.0 g of a colorless clear oily substance.

[0051] The yield of the obtained colorless clear oil was 82.0%. The obtained colorless clear oil was subjected to mass spectrometry detection, and the results were as follows: Figure 1 As shown, the hydrogen spectrum shows a total of 12 hydrogens, which is consistent with the target structure. At the same time, the characteristic triplet peak of the methylene adjacent to the cyano group indicates that compound 1 has been synthesized.

[0052] Example 2

[0053] This embodiment is for preparing compound 1, and its preparation method includes the following steps.

[0054] (1) In a 500 ml three-necked flask, add 7.9 g of potassium carbonate, add 200 ml of water to dissolve, place in an ice bath and cool to 0-5°C, add 20 g of 5-mononitroisosorbide, stir for 30 min, then slowly add 9.2 ml of acrylonitrile dropwise, remove the ice bath after the addition is complete, react at room temperature for 3 h, and after the reaction is completed, stand and separate to obtain an oily crude product in the lower layer.

[0055] (2) The lower layer of crude oily product was diluted with dichloromethane, washed with saturated brine and water in turn, and the organic phases were combined and then dried over anhydrous sodium sulfate to remove dichloromethane to obtain a colorless clear oily substance with a yield of 81.4%.

[0056] Example 3

[0057] This embodiment is for preparing compound 2, and its preparation method includes the following steps.

[0058] (1) In a 500 ml three-necked flask, add 20 g of 5-mononitroisosorbide and 200 ml of dichloromethane as solvent, stir evenly, then add 10.12 ml of pyridine, then slowly add 17.7 ml of trifluoroacetic anhydride dropwise in an ice bath. After the addition is complete, remove the ice bath and react at room temperature for 5 h. After the reaction is complete, pour the solution into the prepared ice water.

[0059] (2) The mixture was washed with 1N hydrochloric acid, saturated brine and water for several times in sequence, the organic phases were combined, dried over anhydrous sodium sulfate, dichloromethane was removed and crystallized with ethanol to obtain a white solid.

[0060] The yield of the obtained white solid was 91.0%. The obtained white solid was subjected to mass spectrometry detection, and the results were as follows: Figure 2 and Figure 3 As shown, the hydrogen spectrum shows a total of 8 hydrogens, which is consistent with the target structure. Figure 3 The characteristic peaks of the fluorine spectrum indicated that compound 2 was synthesized.

[0061] Example 4

[0062] This embodiment is for preparing compound 2, and its preparation method includes the following steps.

[0063] (1) In a 500 ml three-necked flask, add 20 g of 5-mononitroisosorbide and 200 ml of 1.4-dioxane as solvent, stir evenly, then add 10.12 ml of pyridine, then slowly add 17.7 ml of trifluoroacetic anhydride dropwise in an ice bath. After the addition is complete, remove the ice bath and react at room temperature for 5 h. After the reaction is complete, pour the solution into the prepared ice water.

[0064] (2) The product was washed with 1N hydrochloric acid, saturated brine and water for several times in sequence, the organic phases were combined, dried over anhydrous sodium sulfate, dichloromethane was removed and crystallized with ethanol to obtain a white solid. The yield of the obtained white solid was 87.3%.

[0065] Example 5

[0066] This embodiment is for preparing compound 3, and its preparation method includes the following steps.

[0067] (1) In a 500 ml three-necked flask, add 20 g of 5-mononitroisosorbide, about 8.6 g of potassium carbonate, and 200 ml of dimethyl carbonate, which serves as both a solvent and a second reagent. The temperature is raised to 90° C. and the reaction is maintained for 5 hours to obtain a reactant.

[0068] (2) The reactant was filtered to remove potassium carbonate, and then the excess dimethyl carbonate was removed under reduced pressure. The reactant was then recrystallized using a mixed solvent of ethanol / water (1:4, v / v), and then vacuum dried (60° C., 4 h) to obtain a white powder.

[0069] The yield of the obtained white powder was 92.0%. The obtained white powder was subjected to mass spectrometry detection, and the results were as follows: Figure 4 and Figure 5 As shown, the hydrogen spectrum shows a total of 11 hydrogens, which is consistent with the target structure. The chemical shift at 3.75ppm is a characteristic single peak of the terminal methyl group. Figure 5The carbon spectrum showed a total of 8 carbons, which was consistent with the target structure. The characteristic peak of carbonate carbonyl at the chemical shift of 154 ppm further proved that compound 3 was synthesized.

[0070] Example 6

[0071] This embodiment is for preparing compound 3, and its preparation method includes the following steps.

[0072] (1) In a 500 ml three-necked flask, add 20 g of 5-mononitroisosorbide, about 5 g of sodium hydroxide, and 200 ml of dimethyl carbonate, which is used as both a solvent and a second reagent. Stir evenly, heat to 90°C and keep the temperature for 5 hours to obtain a reactant.

[0073] (2) The reactant was filtered to remove sodium hydroxide, and then the excess dimethyl carbonate was removed under reduced pressure. The product was then recrystallized using a mixed solvent of ethanol / water (1:4, v / v), and then vacuum dried (60° C., 4 h) to obtain a white powder. The yield of the obtained white powder was 87.0%.

[0074] Part II: Application of 5-nitroisosorbide derivatives in batteries

[0075] 1.1 Preparation of non-aqueous electrolyte:

[0076] In a glove box filled with nitrogen (O2 <1ppm, H2O <1ppm), ethylene carbonate (EC) and ethyl methyl carbonate (EMC) were mixed in a mass ratio of 3:7 to obtain 87g of a mixed solvent as an organic solvent, and 1g of compound 1 obtained in Example 1, compound 2 obtained in Example 3, and compound 3 obtained in Example 5 were added to obtain a mixed solution. The mixed solution was sealed and packaged and placed in a quick freezer (-4°C) for 2h before being taken out. In a glove box filled with nitrogen (O2 <1ppm, H2O <1ppm), 12g of lithium hexafluorophosphate (LiPF6) was slowly added to the mixed solution, and non-aqueous electrolyte 1#, non-aqueous electrolyte 2#, and non-aqueous electrolyte 3# were obtained after being mixed evenly.

[0077] In a glove box filled with nitrogen (O2 <1ppm, H2O <1ppm), 87g of the mixed solvent obtained by mixing ethylene carbonate (EC) and ethyl methyl carbonate (EMC) in a mass ratio of 3:7 was used as an organic solvent. 88g of the mixed solvent obtained by mixing was used as an organic solvent. The organic solvent was sealed and packaged and placed in a quick freezer (-4°C) for 2h and then taken out. In a glove box filled with nitrogen (O2 <1ppm, H2O <1ppm), 12g of lithium hexafluorophosphate (LiPF6) was slowly added to the mixed solution, and non-aqueous electrolyte 4# was prepared after mixing.

[0078] 1.2 Preparation of positive electrode:

[0079] The lithium iron material LiFePO4, the conductive agent SuperP, the adhesive PVDF and the carbon nanotube (CNT) were mixed evenly in a mass ratio of 96.5:1.5:1:1 to form a lithium ion battery positive electrode slurry with a certain viscosity, which was coated on the aluminum foil for the current collector. The coating amount was 165.5g / m 2 , dried at 85°C and then cold pressed; then trimmed, cut into pieces, and slit, and after slitting, dried at 85°C for 4 hours under vacuum conditions, and the tabs were welded to make lithium-ion battery positive electrodes that meet the requirements.

[0080] 1.3 Preparation of negative electrode sheet:

[0081] Artificial graphite is mixed with conductive agent SuperP, thickener CMC and adhesive SBR (styrene-butadiene rubber latex) in a mass ratio of 95:1.5:1.0:2.5 to make a slurry, which is evenly mixed. The mixed slurry is applied on both sides of the copper foil, and then dried and rolled to obtain a negative electrode sheet, thereby making a lithium-ion battery negative electrode sheet that meets the requirements.

[0082] 1.4 Preparation of lithium-ion batteries:

[0083] The positive electrode sheet, negative electrode sheet and diaphragm prepared according to the above process were laminated to form a lithium-ion battery with a thickness of 4.7mm, a width of 55mm, a length of 60mm and a total capacity of 2Ah. They were vacuum-baked at 75°C for 10h and injected with non-aqueous electrolyte 1#, non-aqueous electrolyte 2#, non-aqueous electrolyte 3# and non-aqueous electrolyte 4# respectively. After standing for 24h, they were charged to 3.65V with a constant current of 0.1C (200mA), and then charged with a constant voltage of 3.65V until the current dropped to 0.05C (100mA); then discharged to 2.5V with 0.2C (400mA), repeated twice, and finally charged to 3.65V with 0.1C (200mA), completing the production of lithium-ion battery 1#, lithium-ion battery 2#, lithium-ion battery 3# and lithium-ion battery 4#.

[0084] The performance tests were conducted on lithium-ion battery 1#, lithium-ion battery 2#, lithium-ion battery 3#, and lithium-ion battery 4#. The test results are shown in Table 1. The test conditions are as follows.

[0085] (1) High rate cycle performance test

[0086] At room temperature (25°C), the lithium-ion battery was charged and discharged at 3.0C / 3.0C (the battery discharge capacity was recorded as C0) with an upper voltage limit of 4.1V; then charged and discharged at 3.0C / 3.0C for 500 cycles, and the capacity retention rate was calculated.

[0087] Capacity retention rate = (battery capacity C1 after 500 cycles / battery initial capacity C0) * 100%

[0088] (2) Low temperature discharge test

[0089] At room temperature (25°C), the lithium-ion battery is charged and discharged at 0.5C / 0.5 (battery cut-off voltage is 3.0V, discharge capacity is C0), and the upper limit voltage is 4.1V (cut-off current 0.05C). Then the battery is fully charged to 4.1V (cut-off current 0.05C) at 0.5C at room temperature (25°C), and then the battery is transferred to -20°C and left for 4h, and discharged to 3.0V at 0.5C, and the discharge capacity is C1. The capacity retention rate is calculated.

[0090] Capacity retention rate = (C1 / C0)*100%

[0091] Table 1 Electrochemical performance test results of each example

[0092]

[0093] From the results in Table 1, it can be seen that the cycle, low temperature and rate performance of lithium-ion batteries 1#~3# are better than those of lithium-ion battery 4#. This is because lithium-ion batteries 1#~3# use 5-nitroisosorbide derivatives as additives, which can form a good nitride protective film with lower solubility at the interface of positive and negative electrode materials, and have lower interface impedance, thereby improving the low temperature and rate performance of the battery.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A 5-nitroisosorbide derivative, characterized in that: Compound 1, Compound 2 or Compound 3 2. The method for preparing 5-nitroisosorbide derivatives according to claim 1, characterized in that: Includes steps: (1) subjecting 5-mononitroisosorbide to an electrophilic addition reaction with a first reagent in a certain solvent and an acid-binding agent to obtain a primary product, or subjecting 5-mononitroisosorbide to an acylation reaction with a second reagent in a certain solvent and an acid-binding agent to obtain a primary product; (2) Purifying and drying the primary product.

3. The method for preparing 5-nitroisosorbide derivatives according to claim 2, characterized in that: The first reagent is acrylonitrile, and the second reagent is a compound shown in structural formula 1, wherein R is CF3 or OCH3, R` is OH, OCOR or OR``, and R`` is a C1-C3 alkyl group.

4. The method for preparing 5-nitroisosorbide derivatives according to claim 2, characterized in that: The solvent includes at least one of water, dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, ether, benzene, toluene, acetonitrile, ether, cyclohexane, petroleum ether, tetrahydrofuran, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate and propylene carbonate.

5. The method for preparing 5-nitroisosorbide derivatives according to claim 2, characterized in that: The acid binding agent includes at least one of triethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, sodium hydroxide, potassium hydroxide, potassium carbonate and cesium carbonate.

6. The method for preparing 5-nitroisosorbide derivatives according to claim 2, characterized in that: The molar ratio of the 5-mononitroisosorbide ester to the first reagent is 1:1-6, the molar ratio of the 5-mononitroisosorbide ester to the second reagent is 1:1-6, and the molar ratio of the acid binding agent to the 5-mononitroisosorbide ester is 1:0.5-6.

0.

7. The method for preparing 5-nitroisosorbide derivatives according to claim 1, characterized in that: The reaction temperature of the addition reaction is 10-40° C., the reaction time of the addition reaction is 1-10 h, the reaction temperature of the acylation reaction is 10-100° C., and the reaction time of the acylation reaction is 1-10 h.

8. The method for preparing 5-nitroisosorbide derivatives according to claim 1, characterized in that: The purification method is washing, filtering or recrystallization.

9. Use of the 5-nitroisosorbide derivatives prepared by the 5-nitroisosorbide derivatives according to claim 1 or the method for preparing the 5-nitroisosorbide derivatives according to any one of claims 2 to 8 in batteries.

10. An electrolyte solution comprising a non-aqueous organic solvent, an electrolyte salt and an additive, characterized in that: The additive comprises the 5-nitroisosorbide derivatives according to claim 1 or the 5-nitroisosorbide derivatives prepared by the preparation method of the 5-nitroisosorbide derivatives according to any one of claims 2 to 8, and the 5-nitroisosorbide derivatives account for 0.1 to 2.0% of the mass of the electrolyte.

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