Riboflavin derivative-based battery leakage detection method and application

Abstract

The invention belongs to the technical field of battery safety detection, and particularly relates to a battery leakage detection method based on a riboflavin derivative and application. According to the method, on the basis of the stable fluorescence characteristic of riboflavin, when the battery of the electrolyte is prepared, riboflavin is modified and purified, and a riboflavin derivative is selectively added into the electrolyte, so that the riboflavin derivative is kept stable in property when being added into the electrolyte of an acidic or alkaline or organic solvent, and meanwhile, the riboflavin derivative has good solubility with the electrolyte; during detection, the surface of the battery only needs to be irradiated by using an ultraviolet lamp, and the purpose of quickly detecting the electrolyte leakage of the battery in batches can be achieved through visual inspection.

Description

Technical Field

[0001] The invention belongs to the technical field of battery safety detection, and in particular relates to a battery leakage detection method based on riboflavin derivatives and application thereof. Background Art

[0002] During use, the battery may swell and deform or the shell may crack, causing electrolyte leakage due to aging, high temperature, impact, abnormal internal chemical reactions, etc. Battery electrolytes can be divided into three categories: acid electrolytes, alkaline electrolytes, and organic electrolytes.

[0003] The main component of acidic electrolyte is sulfuric acid solution, such as lead-acid batteries, acid zinc-manganese batteries, etc.

[0004] The main component of alkaline electrolyte is potassium hydroxide solution, such as nickel-cadmium storage battery, nickel-metal hydride storage battery, alkaline zinc-manganese battery, etc. Organic electrolyte is represented by lithium-ion battery electrolyte, which is generally composed of lithium salt and one or more non-aqueous organic solvents. Usually one or more additives are added to the electrolyte to make it have better performance. Lithium salts are mainly divided into inorganic lithium salts and organic lithium salts. Inorganic lithium salts include lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium tetrafluoroborate (LiBF4), etc. Organic lithium salts include lithium dioxalate borate (LiBOB), lithium difluorooxalate borate (LiODFB), lithium bistrifluoromethylsulfonyl imide (LiTFSI) and lithium bisfluorosulfonyl imide (LiFSI). Solvents are mainly carbonates, which are divided into cyclic ethylene carbonate (EC), propylene carbonate (PC), chain dimethyl carbonate (DMC), diethyl carbonate (DEC) and ethyl methyl carbonate (EMC). Electrolyte additives, such as film formers, include vinylene carbonate (VC), vinylene carbonate (VEC), fluoroethylene carbonate (FEC), and Li2CO3.

[0005] It can be seen from the above-mentioned electrolyte components that most of the electrolyte is flammable or inflammable. When it leaks and encounters an ignition source, it will burn violently and further react with other structural materials of the battery to cause thermal runaway of the battery, posing a serious fire and explosion hazard.

[0006] In addition, electrolyte components have certain health hazards such as acute oral toxicity, acute percutaneous toxicity, acute inhalation toxicity, skin corrosion / irritation, severe eye damage / eye irritation, and specific target organ toxicity, and human contact should be strictly prevented. At the same time, the above components also have certain ecotoxicity, which is enough to harm the aquatic environment and soil. It is forbidden to discard them at will and discharge them into sewers or water bodies. Therefore, it is very important to test the battery for electrolyte leakage and detect electrolyte leakage in time.

[0007] At present, the main detection methods for battery electrolyte leakage are manual observation method and pressure detection method. Manual observation method relies on the experience of the detection personnel, and it is difficult to accurately identify the early stage of electrolyte leakage. The pressure detection method uses the interaction between electrolyte leakage and volatilization and environmental pressure for detection. Specifically, it can be divided into two categories. One is to evacuate the battery to form a large differential pressure outside the leaking battery. The electrolyte leaks a large amount due to air pressure at the trace leakage point, and then an appearance inspection is performed. The other is that the electrolyte leaks and volatilizes, causing the environmental pressure to rise, and a pressure sensor is used for testing. The above two methods are only suitable for the detection of a single battery, and the detection steps are complicated, which is not suitable for daily detection of batch batteries.

[0008] Riboflavin has a large conjugated structure, good fluorescence effect, and is cheap and easy to obtain, making it a good fluorescence detection reagent. However, riboflavin molecules are unstable in acidic or alkaline environments and have poor solubility in some solvents, so they are not currently used in the field of battery safety. Summary of the invention

[0009] In view of the problems raised in the background technology, the technical problem to be solved by the present invention is to provide a battery leakage detection method and application based on riboflavin derivatives to solve at least one problem in the background technology. The method is based on the stable fluorescence characteristics of riboflavin. When preparing the battery, riboflavin derivatives are selectively added to the electrolyte according to the different properties of the electrolyte, so that the riboflavin derivatives can maintain stable properties when added to acidic and alkaline electrolytes and will not affect the battery performance; at the same time, it has good solubility in organic battery electrolytes. During detection, only ultraviolet light is needed to irradiate the battery surface, and the purpose of rapid batch detection of battery electrolyte leakage can be achieved by naked eye observation.

[0010] The technical solutions adopted are:

[0011] A battery leakage detection method based on riboflavin derivatives. When preparing an electrolyte battery, riboflavin is modified and purified, and the riboflavin derivative is selectively added to the electrolyte so that the riboflavin derivative maintains stable properties when added to an acidic or alkaline or organic solvent electrolyte, and has good solubility in the electrolyte. During detection, an ultraviolet lamp is used to irradiate the battery surface, and rapid batch detection of battery electrolyte leakage can be achieved by visual observation.

[0012] Preferably, the modification method of riboflavin includes halogenation, alkylation or esterification to ensure that the target molecule is stable under acidic, alkaline or organic solvent conditions and has fluorescent activity.

[0013] Preferably, for an acid battery whose electrolyte component is mainly sulfuric acid solution, the hydroxyl groups in the riboflavin molecules are halogenated and protected, and the specific steps are:

[0014] (1) dissolving riboflavin in an anhydrous ether solvent, and then adding triethylamine;

[0015] (2) Slowly add an appropriate amount of phosphorus trichloride or phosphorus tribromide under ice bath conditions, and react in an ice water bath for 6 to 12 hours after the addition is completed. The reaction equation (halogenation reaction) is:

[0016]

[0017] The entire reaction process must be carried out under the protection of an inert gas such as nitrogen or argon, and the progress of the reaction is monitored by thin layer chromatography (using existing technology);

[0018] (3) After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, silica gel (appropriate amount) is added to the solution, and the ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel;

[0019] (4) The mixed powder is spread evenly on the top of a silica gel column and separated by column chromatography using an eluent to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column.

[0020] The eluent is evaporated by rotary evaporation to obtain a light yellow or dark yellow halogenated riboflavin derivative.

[0021] As a further preference, the anhydrous ether solvent includes diethyl ether, propyl ether, isopropyl ether, methyl tert-butyl ether, anisole, tetrahydrofuran, and dioxane, with a concentration range of 0.01 to 2 mol / L; but the anhydrous ether solvents used in the present invention include but are not limited to the above-mentioned types.

[0022] The ratio of triethylamine to riboflavin is greater than 4:1.

[0023] As a further preference, the ratio of phosphorus trichloride or phosphorus tribromide to riboflavin is greater than 1.4:1.

[0024] As a further preference, the eluent is a mixture of petroleum ether and toluene, wherein the volume ratio of toluene to petroleum ether is 1:5-20.

[0025] Preferably, for alkaline batteries whose main electrolyte component is potassium hydroxide solution, the imide in the riboflavin molecule is alkylated and protected, and the specific steps are:

[0026] (1) dissolving riboflavin in a protic solvent, adding 1 to 1.1 equivalents of a strong base to the solution system, and stirring at room temperature;

[0027] (2) After the base is completely dissolved, 1 to 1.1 equivalents of monohalogenated alkane are slowly added dropwise to the solution. After the addition of the halogenated alkane is completed, the solution is stirred at room temperature and pressure for 6 to 12 hours. The reaction equation (alkylation reaction) is:

[0028]

[0029] The reaction progress was monitored by thin layer chromatography during the reaction;

[0030] (3) After the reaction is complete, a weak acid is added to neutralize the excess alkali, and then the inorganic salt generated by the reaction is filtered out;

[0031] (4) adding silica gel (appropriate amount) to the reaction solution, removing the protic solvent in the system by rotary evaporation, and obtaining a dry powder mixture of the reaction product and silica gel;

[0032] (5) spreading the mixed powder on the top of a silica gel column and performing column chromatography separation using an eluent to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column;

[0033] (6) The eluent is evaporated by rotary evaporation to obtain a white or light yellow alkyl-protected riboflavin derivative.

[0034] As a further preference, the protic solvent includes methanol, ethanol, propanol, butanol, isobutanol, tert-butanol, and the concentration range is 0.05 to 2 mol / L;

[0035] However, the protic solvents used in the present invention include but are not limited to the above-mentioned types.

[0036] As further preferred, the strong base includes lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide;

[0037] However, the strong base used in the present invention includes but is not limited to the above-mentioned types.

[0038] As further preferred, the monohalogenated alkanes include ethyl bromide, propyl bromide, n-butyl chloride, tert-butyl chloride, tert-butyl bromide, cyclopentane chloride, cyclopentane bromide;

[0039] However, the monohalogenated alkanes used in the present invention include but are not limited to the types mentioned above.

[0040] As a further preference, the eluent is a mixture of petroleum ether and ethyl acetate, wherein the volume ratio of ethyl acetate to petroleum ether is 1:10-50.

[0041] Preferably, for lithium-ion batteries whose electrolyte solvent components are organic solvents such as ethylene carbonate, propylene carbonate, chain dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, the hydroxyl groups on the side chains of riboflavin molecules are subjected to esterification reaction, and the specific steps are as follows:

[0042] (1) dissolving riboflavin in an organic solvent, and then adding triethylamine;

[0043] (2) Slowly add an appropriate amount of acetyl chloride in an ice bath, and react in an ice bath for 6 to 12 hours after the addition is completed. The reaction equation (esterification reaction) is:

[0044]

[0045] The entire reaction process was carried out under anhydrous dry conditions (i.e., the container containing the reactants must be sewage-dried), and the progress of the reaction was monitored by thin-layer chromatography during the reaction;

[0046] (3) After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out;

[0047] (4) adding silica gel to the solution, removing the ether solvent in the system by rotary evaporation, and obtaining a dry powder mixture of the reaction product and silica gel;

[0048] (5) spreading the mixed powder on the top of a silica gel column, and performing column chromatography separation using an eluent ranging from petroleum ether to ethyl acetate in a ratio of 100:1 to 5:1 to obtain a product portion with the smallest polarity that is eluted first from the chromatographic column;

[0049] (6) The eluent is evaporated by rotary evaporation to obtain a light yellow esterified riboflavin derivative.

[0050] As a further preference, the organic solvent is a non-alcoholic solvent that is stable under acidic conditions, including dichloromethane, ethyl acetate, toluene, xylene, ether, tetrahydrofuran, and dioxane, with a concentration range of 0.01 to 2 mol / L; the organic solvents used in the present invention include but are not limited to the above types.

[0051] The ratio of triethylamine to riboflavin is greater than 4:1, the ratio of acetyl chloride to riboflavin is greater than 4:1, and the amount of acetyl chloride used is less than the amount of triethylamine used.

[0052] As a further preference, the eluent is a mixture of petroleum ether and ethyl acetate, wherein the volume ratio of ethyl acetate to petroleum ether is 1:5-100.

[0053] A battery leakage detection method based on riboflavin derivatives is applied to leakage detection of batteries using electrolytes, wherein the batteries using electrolytes include lithium batteries, lead-acid batteries, cadmium-nickel batteries, nickel-hydrogen batteries, zinc-silver batteries, alkaline zinc-manganese batteries, and acid zinc-manganese batteries, and can also be used for monitoring battery packs.

[0054] Compared with the prior art, the present invention is beneficial in that:

[0055] During the production process of the battery of the present invention, a synthetically modified riboflavin derivative that is compatible with the electrolyte and has stable fluorescence characteristics is added, and whether the electrolyte is leaking can be directly determined by ultraviolet light scanning and naked eye observation, thereby solving the problem of difficulty in determining battery leakage.

[0056] This method is suitable for the detection of single-chip batteries and can also be used for monitoring battery packs. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a schematic diagram of the detection method of the present invention. DETAILED DESCRIPTION

[0058] The drawings are for illustrative purposes only; in order to better illustrate the present embodiment, some components in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product.

[0059] For those skilled in the art, some well-known structures and their descriptions in the drawings may be omitted, and therefore, they should not be understood as limitations of the present invention.

[0060] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention is further described in detail below in combination with embodiments and drawings. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0061] Example 1

[0062] like Figure 1 As shown, a battery leakage detection method based on riboflavin derivatives is provided. When preparing a battery with electrolyte, riboflavin is modified and purified, and riboflavin derivatives are selectively added to the electrolyte, so that the riboflavin derivatives can maintain stable properties and have fluorescent activity when added to an acidic or alkaline electrolyte, and at the same time, have good solubility in the electrolyte;

[0063] During the inspection, ultraviolet light is used to irradiate the battery surface, and battery electrolyte leakage can be quickly detected in batches through visual observation.

[0064] In this embodiment, in a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0065] The specific steps are:

[0066] Prepare 500 mL of 1 mol / L riboflavin ether solution.

[0067] 2.05 mol of triethylamine was added to the solution, and 0.7 mol of phosphorus trichloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 6 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0068] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0069] The mixed powder is spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether: toluene = 10:1 to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column.

[0070] The eluent was rotary evaporated to obtain a light yellow chlororiboflavin derivative with a reaction yield of 73%.

[0071] The riboflavin molecules modified by the above method were added to the electrolyte of the lead-acid battery, and the concentration was controlled to be 1mmol / L. A small amount of the solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in the environment of 5mol / L H2SO4 solution.

[0072] Example 2

[0073] A battery leakage detection method based on riboflavin derivatives. In this embodiment, for a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0074] The specific steps are:

[0075] Prepare 500mL of 1 mol / L riboflavin tetrahydrofuran solution.

[0076] 2.05 mol of triethylamine was added to the solution, and 0.7 mol of phosphorus tribromide was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 10 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0077] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the tetrahydrofuran solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0078] The mixed powder was spread on the upper part of the silica gel column, and column chromatography was performed using an eluent in the range of petroleum ether: toluene = 5:1 to obtain the first part of the product eluted from the column.

[0079] The eluent was rotary evaporated to obtain an orange-yellow chlororiboflavin derivative with a reaction yield of 60%.

[0080] The riboflavin molecules modified by the above method were added to the lead-acid battery electrolyte, and the concentration was controlled to be 0.5mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in a 5mol / L H2SO4 solution environment.

[0081] Example 3

[0082] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the zinc-manganese battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution, needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0083] The specific steps are:

[0084] Prepare 500mL of 1mol / L riboflavin ethanol solution.

[0085] 0.55 mol of potassium tert-butoxide was added to the solution, and 0.5 mol of tert-butane chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 6 hours. The reaction progress was monitored by thin layer chromatography during the reaction.

[0086] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the potassium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the ethanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0087] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=30:1 to obtain the first part of the product eluted from the column.

[0088] The eluent was rotary evaporated to obtain a light yellow tert-butyl-substituted riboflavin derivative with a reaction yield of 81%.

[0089] The riboflavin molecules modified by the above method were added to the electrolyte of alkaline zinc-manganese battery, and the concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0090] Example 4

[0091] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the lithium hexafluorophosphate battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0092] The specific steps are:

[0093] Prepare 500mL of 1 mol / L riboflavin methanol solution.

[0094] 0.55 mol of sodium ethoxide was added to the solution, and 0.5 mol of chlorocyclohexane was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 8 hours. During the reaction, the reaction progress was monitored by thin layer chromatography.

[0095] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the sodium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the methanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0096] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate = 50:1 to obtain the first part of the product eluted from the column.

[0097] The eluent was rotary evaporated to obtain a light yellow tert-butyl-substituted riboflavin derivative with a reaction yield of 81%.

[0098] The riboflavin molecules modified by the above method were added to the electrolyte of lithium hexafluorophosphate battery, and its concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0099] Example 5

[0100] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the main component of the electrolyte is an organic solvent. In order to enhance the solubility of the riboflavin derivatives in the system, the hydroxyl groups on the side chains of the riboflavin molecules need to be esterified. The specific steps are:

[0101] Prepare 500mL of 1mol / L riboflavin dichloromethane solution.

[0102] 2.05 mol of triethylamine was added to the solution, and 2 mol of acetyl chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the solution was dried over anhydrous conditions and reacted at 0°C for 6 hours. During the reaction, the reaction progress was monitored by thin layer chromatography.

[0103] After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the dichloromethane in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0104] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=100:1 to obtain the first part of the product eluted from the column.

[0105] The eluent was rotary evaporated to obtain a pale yellow acetic acid-esterified riboflavin derivative with a reaction yield of 70%.

[0106] The riboflavin molecules modified by the above method are added to the zinc-manganese battery electrolyte, and the concentration is controlled to be 0.1mmol / L. A small amount of solution is dropped on a thin layer chromatography plate, and fluorescence can be observed by naked eyes under ultraviolet light. In the dimethyl carbonate solution environment, the solubility of the esterified derivative is increased from 0.5g / 100mL to 5.2g / 100mL compared with the unmodified riboflavin. Therefore, fluorescence can be detected at low concentrations, and the solubility of the modified molecules in organic solvents will be significantly improved.

[0107] Example 6

[0108] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the main component of the electrolyte is an organic solvent. In order to enhance the solubility of the riboflavin derivatives in the system, the hydroxyl groups on the side chains of the riboflavin molecules need to be esterified. The specific steps are:

[0109] Prepare 500mL of 1 mol / L riboflavin ethyl acetate solution.

[0110] 2.05 mol of triethylamine was added to the solution, and 2 mol of propionyl chloride was slowly added dropwise in an ice bath. After the addition was completed, the solution was dried over anhydrous conditions and reacted at 0°C for 12 hours. During the reaction, the reaction progress was monitored by thin layer chromatography.

[0111] After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the ethyl acetate in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0112] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=80:1 to obtain the first part of the product eluted from the column.

[0113] The eluent was rotary evaporated to obtain a pale yellow propionate-esterified riboflavin derivative with a reaction yield of 61%.

[0114] The riboflavin molecules modified by the above method were added to the zinc-manganese battery electrolyte, and the concentration was controlled to be 0.1mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In the ethylene carbonate solution environment, the solubility of the esterified derivative was increased from 0.4g / 100mL to 4.7g / 100mL compared with the unmodified riboflavin.

[0115] Example 7

[0116] In this embodiment, in a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0117] The specific steps are:

[0118] Prepare 500 mL of 1 mol / L riboflavin isopropyl ether solution.

[0119] 2.04 mol of triethylamine was added to the solution, and 0.68 mol of phosphorus trichloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 6 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0120] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the isopropyl ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0121] The mixed powder is spread evenly on the upper part of the silica gel column, and column chromatography is performed using an eluent in the range of petroleum ether: xylene = 10:1 to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column.

[0122] The eluent was rotary evaporated to obtain a pale yellow chlororiboflavin derivative with a reaction yield of 72%.

[0123] The riboflavin molecules modified by the above method were added to the electrolyte of the lead-acid battery, and the concentration was controlled to be 1mmol / L. A small amount of the solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in the environment of 5mol / L H2SO4 solution.

[0124] Example 8

[0125] A battery leakage detection method based on riboflavin derivatives. In this embodiment, for a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0126] The specific steps are:

[0127] Prepare 500mL of 1mol / L riboflavin dioxane solution.

[0128] 2.05 mol of triethylamine was added to the solution, and 0.7 mol of phosphorus trichloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 10 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0129] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the dioxane solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0130] The mixed powder was spread on the upper part of the silica gel column, and column chromatography was performed using an eluent in the range of petroleum ether: toluene = 5:1 to obtain the first part of the product eluted from the column.

[0131] The eluent was rotary evaporated to obtain an orange-yellow chlororiboflavin derivative with a reaction yield of 70%.

[0132] The riboflavin molecules modified by the above method were added to the lead-acid battery electrolyte, and the concentration was controlled to be 0.5mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in a 5mol / L H2SO4 solution environment.

[0133] Example 9

[0134] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the zinc-manganese battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution, needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0135] The specific steps are:

[0136] Prepare 500 mL of 1 mol / L riboflavin isopropanol solution.

[0137] 0.55 mol of sodium tert-butoxide was added to the solution, and 0.5 mol of tert-butane chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 6 hours. The reaction progress was monitored by thin layer chromatography during the reaction.

[0138] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the sodium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the isopropanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0139] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate = 50:1 to obtain the first part of the product eluted from the column.

[0140] The eluent was rotary evaporated to obtain a light yellow tert-butyl-substituted riboflavin derivative with a reaction yield of 79%.

[0141] The riboflavin molecules modified by the above method were added to the electrolyte of alkaline zinc-manganese battery, and the concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0142] Example 10

[0143] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the lithium hexafluorophosphate battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0144] The specific steps are:

[0145] Prepare 500mL of 1 mol / L riboflavin propanol solution.

[0146] 0.55 mol of potassium tert-butoxide was added to the solution, and 0.5 mol of n-butyl chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 6 hours. The reaction progress was monitored by thin layer chromatography during the reaction.

[0147] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the potassium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the propanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0148] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=80:1 to obtain the first part of the product eluted from the column.

[0149] The eluent was rotary evaporated to obtain a light yellow tert-butyl-substituted riboflavin derivative with a reaction yield of 81%.

[0150] The riboflavin molecules modified by the above method were added to the electrolyte of lithium hexafluorophosphate battery, and its concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0151] Embodiment 11

[0152] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the main component of the electrolyte is an organic solvent. In order to enhance the solubility of the riboflavin derivatives in the system, the hydroxyl groups on the side chains of the riboflavin molecules need to be esterified.

[0153] The specific steps are:

[0154] Prepare 500mL of 1mol / L riboflavin chloroform solution.

[0155] 2.05 mol of triethylamine was added to the solution, and 2 mol of propionyl chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the solution was dried over anhydrous conditions and reacted at 0°C for 6 hours. During the reaction, the reaction progress was monitored by thin layer chromatography.

[0156] After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the chloroform in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0157] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=80:1 to obtain the first part of the product eluted from the column.

[0158] The eluent was rotary evaporated to obtain a pale yellow propionate-esterified riboflavin derivative with a reaction yield of 70%.

[0159] The riboflavin molecules modified by the above method were added to the zinc-manganese battery electrolyte, and the concentration was controlled to be 0.1mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In the dimethyl carbonate solution environment, the solubility of the esterified derivative was increased from 0.5g / 100mL to 5.5g / 100mL compared with the unmodified riboflavin.

[0160] Example 12

[0161] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the main component of the electrolyte is an organic solvent. In order to enhance the solubility of the riboflavin derivatives in the system, the hydroxyl groups on the side chains of the riboflavin molecules need to be esterified.

[0162] The specific steps are:

[0163] Prepare 500 mL of 1 mol / L riboflavin methyl acetate solution.

[0164] 2.05 mol of triethylamine was added to the solution, and 2 mol of propionyl chloride was slowly added dropwise in an ice bath. After the addition was completed, the solution was dried over anhydrous conditions and reacted at 0°C for 12 hours. During the reaction, the reaction progress was monitored by thin layer chromatography.

[0165] After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the ethyl acetate in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0166] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate=80:1 to obtain the first part of the product eluted from the column.

[0167] The eluent was rotary evaporated to obtain a pale yellow propionate-esterified riboflavin derivative with a reaction yield of 61%.

[0168] The riboflavin molecules modified by the above method were added to the zinc-manganese battery electrolyte, and the concentration was controlled to be 0.1mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In the ethylene carbonate solution environment, the solubility of the esterified derivative was increased from 0.4g / 100mL to 3.7g / 100mL compared with the unmodified riboflavin.

[0169] Example 13

[0170] In this embodiment, in a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0171] The specific steps are:

[0172] Prepare 500 mL of 1 mol / L riboflavin methyl tert-butyl ether solution.

[0173] 2.04 mol of triethylamine was added to the solution, and 0.67 mol of phosphorus tribromide was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 12 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0174] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the methyl tert-butyl ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0175] The mixed powder is spread on the upper part of a silica gel column, and column chromatography is performed using an eluent in the range of petroleum ether: toluene = 20:1 to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column.

[0176] The eluent was rotary evaporated to obtain a light yellow brominated riboflavin derivative with a reaction yield of 62%.

[0177] The riboflavin molecules modified by the above method were added to the electrolyte of the lead-acid battery, and the concentration was controlled to be 1mmol / L. A small amount of the solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in the environment of 5mol / L H2SO4 solution.

[0178] Embodiment 14

[0179] A battery leakage detection method based on riboflavin derivatives. In this embodiment, for a lead-acid battery whose main component of electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules need to be halogenated to prevent them from being etherified in the electrolyte and causing changes in properties.

[0180] The specific steps are:

[0181] Prepare 500 mL of 1 mol / L riboflavin methyl ethyl ether solution.

[0182] 2.04 mol of triethylamine was added to the solution, and 0.67 mol of phosphorus trichloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in an ice-water bath for 6 hours. The entire reaction process was anhydrous and oxygen-free and argon was used for protection. The reaction progress was monitored by thin layer chromatography during the reaction.

[0183] After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the methyl ethyl ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0184] The mixed powder was spread on the upper part of the silica gel column and separated by column chromatography using an eluent in the range of petroleum ether: toluene = 20:1 to obtain the first part of the product eluted from the column.

[0185] The eluent was rotary evaporated to obtain a white chlororiboflavin derivative with a reaction yield of 70%.

[0186] The riboflavin molecules modified by the above method were added to the lead-acid battery electrolyte, and the concentration was controlled to be 0.5mmol / L. A small amount of the solution was dropped on a thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no ether compounds were detected within 72 hours in a 5mol / L H2SO4 solution environment.

[0187] Embodiment 15

[0188] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the zinc-manganese battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution, needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0189] The specific steps are:

[0190] Prepare 500mL of 1 mol / L riboflavin n-pentanol solution.

[0191] 0.55 mol of sodium tert-butoxide was added to the solution, and 0.5 mol of tert-butane chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 6 hours. The reaction progress was monitored by thin layer chromatography during the reaction.

[0192] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the sodium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the n-pentanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0193] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate = 35:1 to obtain the first part of the product eluted from the column.

[0194] The eluent was rotary evaporated to obtain a white tert-butyl-substituted riboflavin derivative with a reaction yield of 78%.

[0195] The riboflavin molecules modified by the above method were added to the electrolyte of alkaline zinc-manganese battery, and the concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0196] Example 16

[0197] A battery leakage detection method based on riboflavin derivatives. In this embodiment, the lithium hexafluorophosphate battery whose main component of the electrolyte is potassium hydroxide alkaline battery solution needs to be alkylated to protect the imide in the riboflavin molecule to prevent it from being hydrolyzed in an alkaline environment and causing changes in properties.

[0198] The specific steps are:

[0199] Prepare 500mL of 1mol / L riboflavin tert-butyl alcohol solution.

[0200] 0.56 mol of potassium tert-butoxide was added to the solution, and 0.5 mol of n-butyl chloride was slowly added dropwise under ice bath conditions. After the addition was completed, the reaction was carried out in anhydrous room temperature for 6 hours. The reaction progress was monitored by thin layer chromatography during the reaction.

[0201] After the reaction is completed, a small amount of boric acid is added to remove the remaining alkali in the system, and then the potassium chloride generated in the system is filtered out, an appropriate amount of silica gel is added to the solution, and the tert-butanol solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel.

[0202] The mixed powder was spread on the upper part of a silica gel column and separated by column chromatography using an eluent in the range of petroleum ether:ethyl acetate = 70:1 to obtain the first part of the product eluted from the column.

[0203] The eluent was rotary evaporated to obtain a light yellow tert-butyl-substituted riboflavin derivative with a reaction yield of 75%.

[0204] The riboflavin molecules modified by the above method were added to the electrolyte of lithium hexafluorophosphate battery, and its concentration was controlled to 0.1mmol / L. A small amount of solution was dropped on the thin layer chromatography plate, and fluorescence could be observed by naked eyes under ultraviolet light. In addition, no hydrolysis product was detected within 72 hours in the environment of 10mol / LKOH solution.

[0205] Comparative Example 1

[0206] The riboflavin chloride and riboflavin in Example 1 were added to two groups of 5 mol / L sulfuric acid solutions respectively, and the solutions were sealed and allowed to stand at room temperature.

[0207] After 72 hours, yellow granular precipitate appeared in the sulfuric acid solution of riboflavin. A small amount of solution was taken out and dropped on the thin layer chromatography plate. Under ultraviolet light, no fluorescence was observed with the naked eye; the sulfuric acid solution of riboflavin chloride remained clear. A small amount of solution was taken out and dropped on the thin layer chromatography plate, and fluorescence was observed.

[0208] Comparative Example 2

[0209] The riboflavin butylated derivative and riboflavin in Example 3 were added to two groups of 10 mol / L potassium hydroxide solutions respectively, and the solutions were sealed and allowed to stand at room temperature.

[0210] After 72 hours, yellow flocculent insoluble matter appeared in the potassium hydroxide solution of riboflavin. A small amount of the solution was taken out and dropped on the thin layer chromatography plate. Under ultraviolet light, the fluorescence signal was extremely weak; the potassium hydroxide solution of the riboflavin butylated derivative remained clear. A small amount of the solution was taken out and dropped on the thin layer chromatography plate, and fluorescence could be observed.

[0211] Comparison between the embodiment and comparative examples 1 and 2 shows that:

[0212] The butylated riboflavin molecules can remain stable in acidic and alkaline environments and retain their fluorescence properties; however, the unmodified riboflavin molecules are destroyed under acidic and alkaline conditions, the decomposition products are complex, and the system cannot maintain the solution form, which affects the quality of the electrolyte and loses its fluorescence properties.

[0213] In the description of this specification, unless otherwise clearly specified or limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense.

[0214] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0215] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A battery leakage detection method based on riboflavin derivatives, characterized in that: When preparing electrolyte batteries, riboflavin is modified and purified, and riboflavin derivatives are selectively added to the electrolyte so that the riboflavin derivatives remain stable when added to acidic, alkaline or organic solvent electrolytes, and have good solubility in the electrolyte. During detection, ultraviolet light is used to irradiate the battery surface, and rapid batch detection of battery electrolyte leakage can be achieved through visual observation.

2. A battery leakage detection method based on riboflavin derivatives according to claim 1, characterized in that: The modification method of riboflavin includes halogenation, alkylation or esterification to ensure that the target molecule is stable under acidic, alkaline and organic solvent conditions and has fluorescent activity.

3. A battery leakage detection method based on riboflavin derivatives according to claim 2, characterized in that: For acidic batteries whose electrolyte is sulfuric acid solution, the hydroxyl groups in the riboflavin molecules are halogenated and protected. The specific steps are as follows: (1) dissolving riboflavin in an anhydrous ether solvent, and then adding triethylamine; (2) slowly dropwise add an appropriate amount of phosphorus trichloride or phosphorus tribromide under ice bath conditions, and react in an ice water bath for 6 to 12 hours after the dropwise addition is completed. The entire reaction process must be carried out under the protection of inert gas, and the reaction progress is monitored by thin layer chromatography during the reaction; (3) After the reaction is completed, the triethylamine phosphite generated in the system is filtered out, silica gel is added to the solution, and the ether solvent in the system is removed by rotary evaporation to obtain a dry powder mixture of the reaction product and silica gel; (4) The mixed powder is spread evenly on the top of a silica gel column and separated by column chromatography using an eluent to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column. The eluent is evaporated by rotary evaporation to obtain a light yellow or dark yellow halogenated riboflavin derivative.

4. A battery leakage detection method based on riboflavin derivatives according to claim 3, characterized in that: The anhydrous ether solvents include ethyl ether, propyl ether, isopropyl ether, methyl tert-butyl ether, anisole, tetrahydrofuran, and dioxane, with a concentration range of 0.01 to 2 mol / L; the ratio of triethylamine to riboflavin is greater than 4:

1.

5. The battery leakage detection method based on riboflavin derivatives according to claim 3, characterized in that: The ratio of phosphorus trichloride or phosphorus tribromide to riboflavin is greater than 1.4:

1.

6. A battery leakage detection method based on riboflavin derivatives according to claim 3, characterized in that: The eluent is a mixture of petroleum ether and toluene, wherein the volume ratio of toluene to petroleum ether is 1:5-20.

7. A battery leakage detection method based on riboflavin derivatives according to claim 2, characterized in that: For alkaline batteries whose electrolyte is potassium hydroxide solution, the imide in the riboflavin molecule is alkylated and protected. The specific steps are as follows: (1) dissolving riboflavin in a protic solvent, adding 1 to 1.1 equivalents of a strong base to the solution system, and stirring at room temperature; (2) After the base is completely dissolved, 1 to 1.1 equivalents of monohalogenated alkane are slowly added dropwise to the solution. After the addition of the halogenated alkane is completed, the solution is stirred at room temperature and pressure for 6 to 12 hours, and the progress of the reaction is monitored by thin layer chromatography during the reaction; (3) After the reaction is complete, a weak acid is added to neutralize the excess alkali, and then the inorganic salt generated by the reaction is filtered out; (4) adding silica gel to the reaction solution, removing the protic solvent in the system by rotary evaporation, and obtaining a dry powder mixture of the reaction product and silica gel; (5) spreading the mixed powder on the top of a silica gel column and performing column chromatography separation using an eluent to obtain the product portion with the smallest polarity that is eluted first from the chromatographic column; (6) The eluent is evaporated by rotary evaporation to obtain a white or light yellow alkyl-protected riboflavin derivative.

8. The battery leakage detection method based on riboflavin derivatives according to claim 7, characterized in that: The protic solvent includes methanol, ethanol, propanol, butanol, isobutanol, and tert-butanol, with a concentration range of 0.05 to 2 mol / L.

9. The battery leakage detection method based on riboflavin derivatives according to claim 7, characterized in that: The strong base includes lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, sodium ethoxide, potassium ethoxide, and potassium tert-butoxide.

10. The battery leakage detection method based on riboflavin derivatives according to claim 7, characterized in that: Monohalogenated alkanes include ethyl bromide, propyl bromide, n-butyl chloride, tert-butyl chloride, tert-butyl bromide, cyclopentane chloride, and cyclopentane bromide.

11. The battery leakage detection method based on riboflavin derivatives according to claim 7, characterized in that: The eluent is a mixture of petroleum ether and ethyl acetate, wherein the volume ratio of ethyl acetate to petroleum ether is 1:10-50.

12. A battery leakage detection method based on riboflavin derivatives according to claim 2, characterized in that: For lithium-ion batteries whose electrolyte solvent components are organic solvents such as ethylene carbonate, propylene carbonate, chain dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, an esterification reaction is performed on the hydroxyl groups on the side chains of riboflavin molecules. The specific steps are as follows: (1) dissolving riboflavin in an organic solvent, and then adding triethylamine; (2) slowly adding an appropriate amount of acetyl chloride dropwise under ice bath conditions, and reacting in an ice bath for 6 to 12 hours after the addition is complete. The entire reaction process is carried out under anhydrous drying, and the reaction progress is monitored by thin layer chromatography during the reaction; (3) After the reaction is completed, the triethylamine hydrochloride generated in the system is filtered out; (4) adding silica gel to the solution, removing the ether solvent in the system by rotary evaporation, and obtaining a dry powder mixture of the reaction product and silica gel; (5) spreading the mixed powder on the top of a silica gel column, and performing column chromatography separation using an eluent ranging from petroleum ether to ethyl acetate in a ratio of 100:1 to 5:1 to obtain the product portion that is first eluted from the chromatography column; (6) The eluent is evaporated by rotary evaporation to obtain a light yellow esterified riboflavin derivative.

13. A battery leakage detection method based on riboflavin derivatives according to claim 12, characterized in that: The organic solvent is a non-alcoholic solvent that is stable under acidic conditions, including dichloromethane, ethyl acetate, toluene, xylene, ether, tetrahydrofuran, and dioxane, with a concentration range of 0.01 to 2 mol / L; the ratio of triethylamine to riboflavin is greater than 4:1, the ratio of acetyl chloride to riboflavin is greater than 4:1, and the amount of acetyl chloride used is less than the amount of triethylamine used.

14. A battery leakage detection method based on riboflavin derivatives according to claim 12, characterized in that: The eluent is a mixture of petroleum ether and ethyl acetate, wherein the volume ratio of ethyl acetate to petroleum ether is 1:5-100.

15. A battery leakage detection method based on riboflavin derivatives is applied to leakage detection of batteries using electrolytes, wherein the batteries using electrolytes include lithium batteries, lead-acid batteries, cadmium-nickel batteries, nickel-hydrogen batteries, zinc-silver batteries, alkaline zinc-manganese batteries, and acid zinc-manganese batteries. It can also be applied to the detection of battery packs.

Images