A lead-acid battery electrolyte composite additive, electrolyte and preparation method thereof

Abstract

The application relates to the technical field of lead-acid battery electrolyte, and discloses a lead-acid battery electrolyte composite additive, an electrolyte and a preparation method thereof. The electrolyte composite additive comprises the following components: hexadecyl trimethyl ammonium bromide, stannous sulfate, an organic phosphonic acid sodium salt and 1,8-diazabicyclo[5.4.0]undec-7-ene. The electrolyte composite additive solves the problems of fast battery capacity attenuation and short battery service life of the lead-acid battery in a low-temperature environment, and improves the low-temperature resistance of the lead-acid battery.

Description

Technical Field

[0001] This invention relates to the field of lead-acid battery electrolyte technology, and in particular to a composite additive for lead-acid battery electrolyte, an electrolyte, and a method for preparing the same. Background Technology

[0002] Lead-acid batteries are widely used in many fields such as automotive starting, communication base stations, and energy storage systems due to their low overall cost, mature technology, and high recyclability. The electrolyte in lead-acid batteries is an indispensable and important component, playing a role in conducting ions and participating in electrochemical reactions.

[0003] The main components of lead-acid batteries are sulfuric acid and water. Generally, the mass fraction of sulfuric acid is 25%-40%, but the concentration varies depending on the application and type of the lead-acid battery. To improve the performance and lifespan of lead-acid batteries, suitable additives are often added to the electrolyte. Common additives include sodium sulfate, potassium sulfate, phosphoric acid, boric acid, and organic compounds. However, these additives cannot meet the requirements of low-temperature operating environments, causing a significant performance degradation in lead-acid batteries at low temperatures, such as rapid capacity decay and short battery life. Therefore, it is necessary to develop a composite electrolyte additive that can improve the low-temperature performance of lead-acid batteries. Summary of the Invention

[0004] In view of this, the present invention proposes a composite additive for lead-acid battery electrolyte, an electrolyte and a method for preparing the same. This additive can improve the problems of rapid capacity decay and short battery life of lead-acid batteries under low temperature conditions, and improve their low temperature resistance.

[0005] The technical solution of the present invention is implemented as follows: In a first aspect, the present invention provides a composite additive for lead-acid battery electrolyte, comprising the following components: hexadecyltrimethylammonium bromide, stannous sulfate, sodium organic phosphonate and 1,8-diazabicyclo[5.4.0]undec-7-ene.

[0006] Specifically, hexadecyltrimethylammonium bromide (CTAB) reduces the electrode / electrolyte interfacial tension, inhibiting the deposition of large lead sulfate (PbSO4) crystals and optimizing low-temperature ion mobility. The Sn in stannous sulfate (SnSO4)... 2+ The SnO2-Pb composite passivation layer is formed by reacting with the lead electrode, suppressing hydrogen / oxygen evolution side reactions, reducing electrode corrosion, and extending battery life. Sodium organophosphonate selectively adsorbs on the PbO2 surface of the positive electrode, preventing irreversible PbSO4 conversion, delaying the consumption of the positive electrode active material, and improving lifespan; it also complexes impurity ions (Fe... 2+ Cu 2+This reduces dendrite growth and side reactions caused by impurity erosion, further stabilizing performance. 1,8-Dazabicyclo[5.4.0]undec-7-ene (DBU) complexes Pb 2+ It prevents the formation of dense lead sulfate deposits, while weakening the hydrogen bond network, reducing viscosity, and improving electrical conductivity at low temperatures.

[0007] CTAB reduces electrolyte viscosity and optimizes electrode surface reaction efficiency, while DBU disrupts hydrogen bonding and enhances ion migration rates through complexation with metal ions. Together, they synergistically improve battery capacity and reduce ion migration rates at low temperatures. Simultaneously, DBU restricts lead sulfate deposition, mitigating the adverse effects of crystal size on electrode reactivity at low temperatures. Sodium organophosphonate protects the stability of the positive electrode active material and slows irreversible degradation; SnSO4 forms a passivation layer to protect the negative electrode surface, and together they synergistically improve battery cycle life. Furthermore, the passivation layer remains stable at low temperatures, improving the utilization rate of active materials and further enhancing low-temperature performance.

[0008] Based on the above technical solutions, preferably, the mass ratio of hexadecyltrimethylammonium bromide: stannous sulfate: sodium organophosphonate: 1,8-diazabicyclo[5.4.0]undec-7-ene is 1-6:2-9:5-10:2-8.

[0009] Based on the above technical solutions, preferably, the additive also includes phosphatidylserine.

[0010] Specifically, while the aforementioned additives can solve the low-temperature resistance problem of lead-acid batteries, the additive molecules desorb from the electrode surface during repeated charge-discharge cycles, resulting in insufficient regeneration capacity of the protective layer. To address this, this invention adds phosphatidylserine to the aforementioned composite additives. Phospholipid molecules are anchored to the electrode surface via hydrophobic chains, and the polar head groups dynamically adjust their orientation, forming a self-healing interface film. Furthermore, the ordered water molecule network in the phospholipid bilayer can reduce the ion migration activation energy, thereby improving the discharge capacity of lead-acid batteries under environmental conditions.

[0011] Based on the above technical solutions, preferably, the concentration of phosphatidylserine is: the mass ratio of hexadecyltrimethylammonium bromide is 4-8:1-6.

[0012] Based on the above technical solutions, preferably, the organophosphonate sodium salt is one of disodium hydroxyethylidene diphosphonate, pentasodium ethylenediaminetetramethyleneidenephosphonate, pentasodium diethylenetriaminepentamethyleneidenephosphonate, and tetrasodium 2-phosphonobutane-1,2,4-tricarboxylic acid.

[0013] In a second aspect, the present invention provides an electrolyte comprising an electrolyte composite additive.

[0014] Based on the above technical solutions, preferably, the solvent of the electrode liquid has a density of 1.2-1.5 g / cm³. 3 A dilute sulfuric acid solution.

[0015] Based on the above technical solutions, preferably, in the electrolyte, the concentration of hexadecyltrimethylammonium bromide is 0.1wt%-0.6wt%, the concentration of stannous sulfate is 0.2wt%-0.9wt%, the concentration of sodium organophosphonate is 0.5wt%-1.0wt%, the concentration of 1,8-diazabicyclo[5.4.0]undec-7-ene is 0.2wt%-0.8wt%, and the concentration of phosphatidylserine is 0.4wt%-0.8wt%.

[0016] Thirdly, the present invention provides a method for preparing an electrolyte, comprising the following steps:

[0017] The prepared density is 1.2-1.5 g / cm³. 3 A dilute sulfuric acid solution was prepared by sequentially adding hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine. After stirring until homogeneous, the solution was filtered to remove impurities and obtain the electrolyte.

[0018] Based on the above technical solutions, preferably, in order to prevent the oxidation or decomposition of stannous sulfate and 1,8-diazabicyclo[5.4.0]undec-7-ene, the temperature of the solution system is below 40°C when stannous sulfate is added; and the temperature of the solution system is below 50°C when 1,8-diazabicyclo[5.4.0]undec-7-ene is added.

[0019] The composite additive for lead-acid battery electrolyte, the electrolyte, and the preparation method thereof of the present invention have the following advantages over the prior art:

[0020] (1) In the electrolyte composite additive of the present invention, CTAB and DBU synergistically improve the migration rate of ions under low temperature conditions and increase battery capacity. Sodium organophosphonate and SnSO4 synergistically improve battery cycle life. In addition, the passivation layer remains stable at low temperature, which is beneficial to improving the utilization rate of active materials and further improving low temperature performance.

[0021] (2) The phosphatidylserine in the composite additive of the present invention has phospholipid molecules anchored to the electrode surface through hydrophobic chains, and the polar head groups dynamically adjust their orientation to form an interface film with self-healing function. In addition, the ordered water molecule network in the phospholipid bilayer can reduce the activation energy of ion migration and further improve its low-temperature resistance. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] The cetyltrimethylammonium bromide (CTAB), stannous sulfate, disodium hydroxyethylidene diphosphonate, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and phosphatidylserine described in this invention were all purchased from the market. Specifically, phosphatidylserine (CAS: 51446-62-9) was purchased from Jiangxi Ruiwei Biotechnology Co., Ltd., and the sodium organophosphonate was purchased from Shandong Kairui Chemical Co., Ltd.

[0024] Example 1

[0025] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, disodium hydroxyethylidene diphosphonate and 1,8-diazabicyclo[5.4.0]undec-7-ene.

[0026] The electrolyte is prepared as follows:

[0027] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0028] S2, 4g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 5g of stannous sulfate was added at 30-40℃ and stirring was continued for 10 min; then 8g of disodium hydroxyethylidene diphosphonate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then 5g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, controlling the temperature ≤50℃, and stirring was carried out for 20 min. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure that the electrolyte was transparent and free of particles.

[0029] Example 2

[0030] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, disodium hydroxyethylidene diphosphonate, and 1,8-diazabicyclo[5.4.0]undec-7-ene and phosphatidylserine.

[0031] The electrolyte is prepared as follows:

[0032] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0033] S2, 4g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 5g of stannous sulfate was added at 30-40℃ and stirred for another 10 min; next, 8g of disodium hydroxyethylidene diphosphonate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then, 5g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, with the temperature controlled ≤50℃, and stirred for 20 min; finally, 6g of phosphatidylserine was slowly added and stirred for 30 min until the system was homogeneous. Undissolved impurities were removed through a 0.45 μm filter membrane to ensure the electrolyte was transparent and free of particles.

[0034] Example 3

[0035] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, pentasodium ethylenediaminetetramethylenephosphonate, and 1,8-diazabicyclo[5.4.0]undec-7-ene and phosphatidylserine.

[0036] The electrolyte is prepared as follows:

[0037] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0038] S2, 4g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 5g of stannous sulfate was added at 30-40℃ and stirred for another 10 min; next, 8g of pentasodium ethylenediaminetetramethylenephosphonate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then, 5g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, with the temperature controlled at ≤50℃, and stirred for 20 min; 6g of phosphatidylserine was pre-dissolved in water and then added to the electrolyte, and stirred for 30 min until the system was homogeneous. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure the electrolyte was transparent and free of particles.

[0039] Example 4

[0040] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, diethylenetriaminepentamethylphosphonate pentasodium, 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine.

[0041] The electrolyte is prepared as follows:

[0042] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0043] S2, 1g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 3g of stannous sulfate was added at 30-40℃ and stirred for another 10 min; then 5g of diethylenetriaminepentamethylidenephosphonate pentasodium was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then 4g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, with the temperature controlled at ≤50℃, and stirred for 20 min; 4g of phosphatidylserine was pre-dissolved in water and then added to the electrolyte, and stirred for 30 min until the system was homogeneous. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure the electrolyte was transparent and free of particles.

[0044] Example 5

[0045] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, sodium organic phosphonate salts (disodium hydroxyethylidene diphosphonate, pentasodium ethylenediaminetetramethyleneidene phosphonate, pentasodium diethylenetriaminepentamethyleneidene phosphonate and tetrasodium 2-phosphonobutane-1,2,4-tricarboxylic acid), 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine.

[0046] The electrolyte is prepared as follows:

[0047] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0048] S2, 5g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 2g of stannous sulfate was added at 30-40℃ and stirred for another 10 min; then 10g of sodium organophosphonate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then 2g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, with the temperature controlled at ≤50℃, and stirred for 20 min; 5g of phosphatidylserine was pre-dissolved in water and then added to the electrolyte, and stirred for 30 min until the system was homogeneous. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure the electrolyte was transparent and free of particles.

[0049] Example 6

[0050] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, sodium organic phosphonate salts (disodium hydroxyethylidene diphosphonate, pentasodium ethylenediaminetetramethyleneidene phosphonate, pentasodium diethylenetriaminepentamethyleneidene phosphonate and tetrasodium 2-phosphonobutane-1,2,4-tricarboxylic acid), 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine.

[0051] The electrolyte is prepared as follows:

[0052] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0053] S2, 6g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 8g of stannous sulfate was added at 30-40℃ and stirred for another 10 min; then 10g of sodium organophosphonate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then 7g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, with the temperature controlled at ≤50℃, and stirred for 20 min; 7g of phosphatidylserine was pre-dissolved in water and then added to the electrolyte, and stirred for 30 min until the system was homogeneous. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure the electrolyte was transparent and free of particles.

[0054] Example 7

[0055] The electrolyte composite additive for improving the performance of lead-acid batteries in this embodiment includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, tetrasodium 2-phosphonobutane-1,2,4-tricarboxylate, 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine.

[0056] The electrolyte is prepared as follows:

[0057] S1, concentrated sulfuric acid is added to ultrapure water to prepare a solution with a density of 1.347 g / cm³. 3 1L of dilute sulfuric acid solution;

[0058] S2, 3g of hexadecyltrimethylammonium bromide was added to dilute sulfuric acid and stirred at 300 rpm for 10 min until completely dissolved; then, 6g of stannous sulfate was added at 30-40℃ and stirring was continued for 10 min; then 9g of tetrasodium 2-phosphonobutane-1,2,4-tricarboxylate was added and stirred at 600 rpm for 15 min to ensure complete dissolution in an acidic environment; then 8g of 1,8-diazabicyclo[5.4.0]undec-7-ene was slowly added, controlling the temperature ≤50℃, and stirred for 20 min; 8g of phosphatidylserine was pre-dissolved in water and then added to the electrolyte, and stirred for 30 min until the system was homogeneous. Finally, undissolved impurities were removed through a 0.45 μm filter membrane to ensure that the electrolyte was transparent and free of particles.

[0059] Comparative Example 1

[0060] Compared with Example 1, Comparative Example 1 lacked cetyltrimethylammonium bromide in its electrolyte composite additive, but the rest were the same.

[0061] Comparative Example 2

[0062] Compared with Example 1, Comparative Example 2 lacked stannous sulfate in the electrolyte composite additive, but the rest were the same.

[0063] Comparative Example 3

[0064] Compared with Example 1, Comparative Example 3 lacked disodium hydroxyethylidene diphosphonate in the electrolyte composite additive, but the rest were the same.

[0065] Comparative Example 4

[0066] Compared with Example 1, Comparative Example 4 lacked 1,8-diazabicyclo[5.4.0]undec-7-ene in its electrolyte composite additive, but the rest were the same.

[0067] Comparative Example 5

[0068] The electrolyte in Comparative Example 5, without any composite additives, has a density of 1.347 g / cm³. 3 A dilute sulfuric acid solution.

[0069] Comparative Example 6

[0070] Compared with Example 1, the concentration of cetyltrimethylammonium bromide in the electrolyte composite additive in Comparative Example 6 exceeded the specified range, specifically 12 g / L.

[0071] Comparative Example 7

[0072] Compared with Example 1, the concentration of stannous sulfate in the electrolyte composite additive in Comparative Example 7 exceeded the specified range, specifically 18 g / L.

[0073] Comparative Example 8

[0074] Compared with Example 1, the concentration of disodium hydroxyethylidene diphosphonate in the electrolyte composite additive in Comparative Example 8 exceeded the limit range, specifically 20 g / L.

[0075] Comparative Example 9

[0076] Compared with Example 1, the concentration of 1,8-diazabicyclo[5.4.0]undec-7-ene in the electrolyte composite additive in Comparative Example 9 exceeded the limit range, specifically 15 g / L.

[0077] Comparative Example 10

[0078] Compared with Example 2, the concentration of phosphatidylserine in the electrolyte composite additive in Comparative Example 10 exceeded the limit range, specifically 16 g / L.

[0079] The lead-acid battery electrolytes prepared according to the examples and comparative examples were added to the prepared 5Ah batteries, and formation was performed using the ARBIN battery testing system. Three batteries were prepared for each example and comparative example for testing their cycle life and low-temperature performance at -30°C.

[0080] -30℃ Low Temperature Discharge: Place the battery in a low temperature chamber and set the temperature to -30℃. After 24 hours, discharge the battery at a current of 0.5C in the -30℃ environment and record the time it takes to discharge to 1V.

[0081] -30℃ Low Temperature Capacity: The temperature is set to -30℃. After 24 hours, the discharge capacity is recorded at a current of 0.5C in an environment of -30℃.

[0082] Charge acceptance: The maximum discharge capacity divided by 10 was used as the current value for charging acceptance discharge for 5 hours, followed by placing it in a low temperature chamber (0℃±1℃) for 20 hours. Then the battery was removed and charged at a constant voltage of 2.4V. After 10 minutes, the charging acceptance current A was recorded.

[0083] The cycle life test method refers to GB / T5008.1-2013, and the test temperature is -30℃. The cycle life ends when the battery discharge capacity is lower than 80% of the rated capacity.

[0084] Table 1 Performance test results of lead-acid batteries

[0085]

[0086] As shown in Table 1, the lead-acid batteries assembled using the electrolyte of the examples have higher charge-discharge capacity, capacity, and lifespan under low-temperature conditions than the comparative examples, proving that the composite additive of the present invention significantly improves the low-temperature performance of lead-acid batteries.

[0087] As can be seen from Examples 1-2, the addition of phosphatidylserine significantly improves the charge-discharge capacity, capacity, and lifespan of lead-acid batteries. This indicates that phosphatidylserine inhibits the shedding of active material membranes through its molecular membrane. In addition, the hydrophobic chain of phosphatidylserine complexes with DBU, improving conductivity, optimizing low-temperature mass transfer, and further enhancing the low-temperature performance of lead-acid batteries.

[0088] Comparative Examples 1-4 show that the lack of any one of hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, or 1,8-diazabicyclo[5.4.0]undec-7-ene significantly reduces the low-temperature performance of lead-acid batteries, thus demonstrating the synergistic effect among the components. Comparative Examples 6-10 show that the amounts of hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine are not necessarily better the higher they are. Exceeding the specified range increases the viscosity of the electrolyte, hinders ion migration, and also generates electrochemical side reactions, leading to a decrease in the low-temperature performance of the lead-acid battery.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite additive for lead-acid battery electrolyte, characterized in that: It includes the following components: hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, and 1,8-diazabicyclo[5.4.0]undec-7-ene; The sodium organophosphonate salt is one of disodium hydroxyethylidene diphosphonate, pentasodium ethylenediaminetetramethyleneidene phosphonate, pentasodium diethylenetriaminepentamethyleneidene phosphonate, and tetrasodium 2-phosphonobutane-1,2,4-tricarboxylic acid; The mass ratio of hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, and 1,8-diazabicyclo[5.4.0]undec-7-ene is 1-6:2-9:5-10:2-8.

2. The composite additive for lead-acid battery electrolyte as described in claim 1, characterized in that: The additives also include phosphatidylserine.

3. The composite additive for lead-acid battery electrolyte as described in claim 2, characterized in that: The concentration of phosphatidylserine is: the mass ratio of hexadecyltrimethylammonium bromide is 4-8:1-6.

4. An electrolyte, characterized in that: Includes the electrolyte composite additive as described in any one of claims 1-3.

5. The electrolyte as described in claim 4, characterized in that: The solvent of the electrolyte has a density of 1.2-1.5 g / cm³. 3 A dilute sulfuric acid solution.

6. The electrolyte as described in claim 5, characterized in that: In the electrolyte, the concentration of hexadecyltrimethylammonium bromide is 0.1wt%-0.6wt%, the concentration of stannous sulfate is 0.2wt%-0.9wt%, the concentration of sodium organophosphonate is 0.5wt%-1.0wt%, the concentration of 1,8-diazabicyclo[5.4.0]undec-7-ene is 0.2wt%-0.8wt%, and the concentration of phosphatidylserine is 0.4wt%-0.8wt%.

7. A method for preparing an electrolyte according to any one of claims 4-6, characterized in that: Includes the following steps: The prepared density is 1.2-1.5 g / cm³. 3 A dilute sulfuric acid solution was prepared by sequentially adding hexadecyltrimethylammonium bromide, stannous sulfate, sodium organophosphonate, 1,8-diazabicyclo[5.4.0]undec-7-ene, and phosphatidylserine. After stirring until homogeneous, the solution was filtered to remove impurities and obtain the electrolyte.

8. The method for preparing an electrolyte as described in claim 7, characterized in that: When stannous sulfate is added, the temperature of the solution system is below 40°C; when 1,8-diazabicyclo[5.4.0]undec-7-ene is added, the temperature of the solution system is below 50°C.

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