Application of 4-methoxyphenylethylamine
By adding 4-methoxyphenylethylamine as an electrolyte additive to lithium-ion batteries, the problem of limited improvement in the cycle performance of lithium-ion batteries has been solved, enabling the restoration of old battery capacity and the improvement of new battery performance, delaying battery degradation, and reducing usage costs.
Patent Information
- Application Number
- CN202411118904.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-15
- Publication Date
- 2026-03-03
AI Technical Summary
Existing lithium-ion batteries have limited improvement in cycle performance, especially after 70 cycles when the discharge capacity drops significantly, rendering the battery unusable. It is necessary to effectively slow down the rate of discharge capacity decay to reduce usage costs.
4-Methoxyphenylethylamine is added to old lithium-ion batteries as an electrolyte additive in a ratio of EC:EMC:4-methoxyphenylethylamine:lithium hexafluorophosphate = 9:21:10:1.0 mol/L to restore battery capacity. In new lithium-ion batteries, electrolyte containing 4-methoxyphenylethylamine is added directly in the same ratio for use as an electrolyte.
It slows down the rate of discharge capacity decline of old lithium-ion batteries, improves the cycle performance and lifespan of batteries, reduces usage costs, enables the reuse of old batteries, and improves the discharge capacity retention rate of new batteries.
Smart Images
Figure CN121601818A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lithium-ion battery technology, and in particular to the application of 4-methoxyphenylethylamine in the capacity restoration of old lithium-ion batteries and its application in lithium-ion battery electrolytes. Background Technology
[0002] With increasing global emphasis on environmental protection, lithium-ion batteries are playing an increasingly important role as a clean energy source in the power and automotive industries. Currently, lithium-ion batteries are widely used in power grids and for energy storage in wind and solar power, as well as for backup power for residential and commercial use and for powering two-wheeled, three-wheeled, and automobile vehicles.
[0003] Currently, whether in energy storage or automotive power applications, with relatively stable battery energy density, improving the cycle performance of lithium-ion batteries is fundamental to reducing their operating costs and increasing user satisfaction. Lithium-ion batteries mainly consist of a casing, positive and negative electrodes, a separator, and an electrolyte. Existing literature and patents have disclosed methods for improving the cycle performance of lithium-ion batteries through improvements in positive electrode materials, negative electrode materials, and electrolytes.
[0004] Regarding electrolytes, adding additives can effectively slow down the rate of capacity decay of lithium-ion batteries and improve their cycle performance. However, current additives have limited effect on improving the cycle performance of lithium-ion batteries. After about 70 cycles, the battery's discharge capacity drops from 100% to about 98.5%. After several thousand cycles, the battery's discharge capacity will drop significantly, and it will be considered a waste battery, thus becoming unusable.
[0005] How to effectively slow down the rate of capacity decay of lithium-ion batteries, improve their cycle performance, and further reduce their usage costs is an urgent problem to be solved. Summary of the Invention
[0006] Therefore, there is an urgent need to provide an additive that can improve the performance of lithium-ion battery electrolytes, thereby slowing down the discharge decay rate of lithium-ion batteries and improving their cycle performance; there is also an urgent need to provide an electrolyte additive that can restore the discharge capacity of old batteries, so that old batteries can be reused.
[0007] One of the objectives of this invention is to provide the application of 4-methoxyphenylethylamine in the capacity restoration of old lithium-ion batteries.
[0008] Furthermore, the repair electrolyte containing 4-methoxyphenylethylamine is prepared in advance and then added to the old lithium-ion battery electrolyte.
[0009] Furthermore, the remediation electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate;
[0010] The electrolyte for repair contains EC, EMC, and 4-methoxyphenylethylamine in a mass ratio of 9:21:10, and lithium hexafluorophosphate at a concentration of 1.0 mol / L.
[0011] Furthermore, the 4-methoxyphenylethylamine is directly added to existing lithium-ion batteries.
[0012] Another object of the present invention is to provide the application of 4-methoxyphenylethylamine in lithium-ion battery electrolytes.
[0013] Furthermore, after the lithium-ion battery is formed, an electrolyte containing 4-methoxyphenylethylamine is added.
[0014] Furthermore, the electrolyte containing 4-methoxyphenylethylamine is prepared in advance and then added to the lithium-ion battery casing during the manufacturing process to serve as the electrolyte for the lithium-ion battery.
[0015] Furthermore, the electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate;
[0016] The electrolyte for repair contains EC, EMC, and 4-methoxyphenylethylamine in a mass ratio of 9:21:10, and lithium hexafluorophosphate at a concentration of 1.0 mol / L.
[0017] Furthermore, the 4-methoxyphenylethylamine is directly added to the lithium-ion battery electrolyte.
[0018] The present invention has the following advantages and effects:
[0019] This invention achieves effective restoration of the capacity of old lithium-ion batteries by adding 4-methoxyphenylethylamine or an electrolyte containing 4-methoxyphenylethylamine.
[0020] Furthermore, the rate of decline in discharge capacity of the repaired lithium-ion battery is slower than before repair, thereby effectively improving the discharge capacity retention rate of the old lithium-ion battery, reducing the cost of using lithium-ion batteries, and enabling the old batteries to be reused, which is economical and environmentally friendly.
[0021] This invention slows down the rate of capacity loss in lithium-ion batteries by adding 4-methoxyphenylethylamine to the electrolyte of a new lithium-ion battery, thereby effectively improving the cycle performance of the battery and reducing the cost of using lithium-ion batteries. Attached Figure Description
[0022] Figure 1 This is a comparison chart of the battery cycle-discharge capacity retention rates of Examples 1 and 2. Detailed Implementation
[0023] 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.
[0024] In the embodiments, the used lithium-ion battery refers to an old battery whose discharge capacity has dropped to about 95% or less of the nominal capacity.
[0025] The following examples 1-2 illustrate the application of 4-methoxyphenylethylamine in used lithium-ion battery electrolytes.
[0026] It should be noted that 4-methoxyphenylethylamine has a density of 1.0 g / cm³. 3 Boiling point: 255.2℃, CAS number: 55-81-2, molecular formula: C9H 13 NO, with a molecular weight of 151, 4-methoxyphenylethylamine, also known as methoxyphenylethylamine or MBA, is an organic compound, a colorless liquid with a characteristic odor. It is soluble in water, alcohols, and ethers, but insoluble in non-polar solvents, and is used as a reducing agent in organic synthesis. This invention is the first to propose adding 4-methoxyphenylethylamine as an electrolyte additive to old lithium batteries, which can to some extent restore the capacity of old batteries, improve their cycle life, and can also be added to new batteries to increase their capacity. To fully demonstrate this effect of 4-methoxyphenylethylamine, the following examples illustrate this capability.
[0027] Example 1
[0028] Take one commercially available used lithium iron phosphate battery with a nominal capacity of 20Ah as Sample 1 in Example 1 (the initial discharge capacity of Sample 1 battery was tested to be 88.95% of the nominal capacity). First, test the initial discharge capacity of the battery. Then, add an electrolyte containing 4-methoxyphenylethylamine to Sample 1 battery in a glove box. Then test the discharge capacity after charge and discharge cycles. Finally, calculate the discharge capacity retention rate of the battery.
[0029] (1) Preparation of electrolyte No. 1 containing additives: Electrolyte No. 1 was prepared in a glove box. The concentration of lithium hexafluorophosphate in the prepared electrolyte was 1.0 mol / L. The composition of additives and solvents is shown in Table 1.
[0030] (2) Initial battery capacity test: At 25℃±5℃, use a 5V-40A charge-discharge tester to charge the battery at a constant current (40A) to a voltage of 3.65V, then charge it at a constant voltage of 3.65V to a cutoff current of 1.0A, let it rest for 10 minutes, then discharge it at a constant current of 40A to a voltage of 2.5V, and let it rest for another 10 minutes. This is one cycle, and a total of 10 cycles are performed. The average value of the tested battery capacity is taken as the base of the initial discharge capacity, which is calculated as 100%.
[0031] (3) Electrolyte injection: In the glove box, open the battery injection port and add the electrolyte containing 4-methoxyphenylethylamine prepared in step (1). The amount of electrolyte containing additives added is shown in Table 2. After the electrolyte injection is completed, seal the battery, let it stand for 48 hours, and then perform a charge and discharge test on the machine.
[0032] (4) Charge and discharge test: At 25℃±5℃, use a 5V-40A charge and discharge tester to charge at a constant current (40A) to a voltage of 3.65V, then charge at a constant voltage of 3.65V to a cutoff current of 1.0Ah, let it rest for 10min, then discharge at a constant current of 40A to a cutoff voltage of 2.5V, and let it rest for 10min. This is one cycle. Test the discharge capacity of the battery for the 200th, 400th, 600th, 800th, 1000th, 1200th, 1400th and 1600th cycles, and calculate the capacity retention rate.
[0033] See Table 2 for specific experimental data.
[0034] Example 2
[0035] One used lithium iron phosphate battery with a nominal capacity of 20Ah, purchased from the same batch as the battery in Example 1, was taken as control sample 1 (the initial discharge capacity of control sample 1 was tested to be 88.80% of the nominal capacity). The initial discharge capacity of control sample 1 was tested first, and then electrolyte No. 2 was added to control sample 1 in a glove box. The discharge capacity of the battery after charge and discharge cycles was then tested, and finally the capacity retention rate was calculated.
[0036] (1) Preparation of electrolyte No. 2: Prepare electrolyte No. 2 in a glove box. The concentration of lithium hexafluorophosphate in the prepared electrolyte No. 2 is 1.0 mol / L. The composition of the solvent is shown in Table 1.
[0037] (2) Initial battery capacity test: At 25℃±5℃, use a 5V-40A charge-discharge tester to charge the battery at a constant current (40A) to a voltage of 3.65V, then charge it at a constant voltage of 3.65V to a cutoff current of 1.0A, let it rest for 10 minutes, then discharge it at a constant current of 40A to a voltage of 2.5V, and let it rest for another 10 minutes. This is one cycle, and a total of 10 cycles are performed. The average value of the tested battery capacity is taken as the base of the initial discharge capacity, which is calculated as 100%.
[0038] (3) Injection: In the glove box, open the battery injection port and inject electrolyte No. 2 from step (1). The injection volume is shown in Table 2. After the injection is completed, seal the battery and let it stand for 48 hours before charging and discharging tests.
[0039] (4) Charge and discharge test: At 25℃±5℃, use a 5V-40A charge and discharge tester to charge at a constant current (40A) to a voltage of 3.65V, then charge at a constant voltage of 3.65V to a cutoff current of 1.0Ah, let it rest for 10min, then discharge at a constant current of 40A to a cutoff voltage of 2.5V, and let it rest for 10min. This is one cycle. Test the discharge capacity of the battery for the 200th, 400th, 600th, 800th, 1000th, 1200th, 1400th and 1600th cycles, and calculate the capacity retention rate.
[0040] See Table 2 for specific experimental data.
[0041] It should be noted that the specific formula for calculating the cyclic discharge capacity retention rate is as follows:
[0042] Battery capacity retention rate after Nth discharge cycle = Battery discharge capacity after Nth cycle / Initial discharge capacity before adding electrolyte × 100%.
[0043] The calculated data are shown in Table 2.
[0044] Sample 1 battery was supplemented with an electrolyte containing 4-methoxyphenylethylamine, and the amount added was 1.11g.
[0045] Electrolyte 2 was added to the control sample 1 battery. Electrolyte 2 does not contain 4-methoxyphenylethylamine additive. The amount of electrolyte 2 added was 13.06g.
[0046] Electrolyte 1 and Electrolyte 2 are both prepared from EC (ethylene carbonate) and EMC (methyl ethyl carbonate) in a mass ratio of 3:7, and both contain lithium hexafluorophosphate at a concentration of 1.0 mol / L. The difference is that Electrolyte 1 contains the additive 4-methoxyphenylethylamine, while Electrolyte 2 does not contain the additive 4-methoxyphenylethylamine. Therefore, the only difference between the electrolytes added to the battery in Example 1 and the battery in Example 2 is that the electrolyte added to the battery in Example 1 contains the additive 4-methoxyphenylethylamine.
[0047] From Table 2 and Figure 1 As can be seen, the capacity retention rates of Sample 1 battery after the 400th, 600th, 800th, 1000th, 1200th, 1400th, and 1600th cycles are all higher than those of Comparative Samples 1 and 2 after the 200th, 400th, 600th, 800th, 1000th, 1200th, 1400th, and 1600th cycles. In particular, after 600 cycles, the degradation rate of Sample 1 battery is significantly lower than that of Samples 1 and 2 batteries. This indicates that adding an electrolyte containing 4-methoxyphenylethylamine to the battery can effectively improve the battery's cycle discharge capacity, improve the capacity retention rate of lithium-ion batteries, delay battery degradation, and thus improve battery cycle performance and battery life.
[0048] Compared to sample 1, which contained electrolyte 2 but did not contain 4-methoxyphenylethylamine additive, sample 1 contained electrolyte 1 containing 4-methoxyphenylethylamine. This indicates that 4-methoxyphenylethylamine plays a role in improving the battery capacity retention rate, slowing down the battery degradation rate, and thus improving the battery life.
[0049] Table 1. Composition of solvents and additives in the electrolyte (mass fraction)
[0050] serial number EC EMC 4-Methoxyphenylethylamine Electrolyte No. 1 3 7 5 Electrolyte No. 2 3 7 0
[0051] Table 2 Capacity retention rate of batteries at different cycle counts
[0052]
[0053] Example 3
[0054] By taking a commercially available 20Ah lithium iron phosphate battery and directly adding 4-methoxyphenylethylamine into the battery, the battery's discharge capacity retention rate is improved.
[0055] Example 4
[0056] By taking a brand-new 20Ah lithium iron phosphate battery from the market and adding an electrolyte containing 4-methoxyphenylethylamine, the battery's discharge capacity retention rate was improved.
[0057] The electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate;
[0058] The electrolyte for repair contains EC, EMC, and 4-methoxyphenylethylamine in a mass ratio of 9:21:10, and lithium hexafluorophosphate at a concentration of 1.0 mol / L.
[0059] Example 5
[0060] In the lithium-ion battery manufacturing process, an electrolyte containing 4-methoxyphenylethylamine is added to the lithium-ion battery casing, followed by sealing the casing and formation; this process improves the battery's discharge capacity retention. The electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate; wherein, the mass ratio of EC, EMC, and 4-methoxyphenylethylamine in the repair electrolyte is 9:21:10, and the concentration of lithium hexafluorophosphate is 1.0 mol / L.
Claims
Application of 1,4-methoxyphenylethylamine in the capacity restoration of old lithium-ion batteries.
2. The application of 4-methoxyphenylethylamine according to claim 1 in the capacity restoration of used lithium-ion batteries, characterized in that, The repair electrolyte containing 4-methoxyphenylethylamine is prepared in advance and then added to the old lithium-ion battery electrolyte.
3. The application of 4-methoxyphenylethylamine according to claim 1 in the capacity restoration of used lithium-ion batteries, characterized in that, The remediation electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate; The electrolyte for repair contains EC, EMC, and 4-methoxyphenylethylamine in a mass ratio of 9:21:10, and lithium hexafluorophosphate at a concentration of 1.0 mol / L.
4. The application of 4-methoxyphenylethylamine according to claim 1 in the capacity restoration of used lithium-ion batteries, characterized in that, The 4-methoxyphenylethylamine was directly added to the old lithium-ion battery. Application of 5,4-methoxyphenylethylamine in lithium-ion battery electrolytes.
6. The application of 4-methoxyphenylethylamine according to claim 5 in lithium-ion battery electrolyte, characterized in that, After the lithium-ion battery is formed, an electrolyte containing 4-methoxyphenylethylamine is added.
7. The application of 4-methoxyphenylethylamine according to claim 5 in lithium-ion battery electrolyte, characterized in that, An electrolyte containing 4-methoxyphenylethylamine is prepared in advance and then added to the lithium-ion battery casing during the manufacturing process to serve as the electrolyte for the lithium-ion battery.
8. The application of 4-methoxyphenylethylamine according to claim 6 or 7 in lithium-ion battery electrolyte, characterized in that, The electrolyte containing 4-methoxyphenylethylamine includes a solvent, a lithium salt, and 4-methoxyphenylethylamine; the solvent includes EC and EMC; the lithium salt is lithium hexafluorophosphate; The electrolyte for repair contains EC, EMC, and 4-methoxyphenylethylamine in a mass ratio of 9:21:10, and lithium hexafluorophosphate at a concentration of 1.0 mol / L.
9. The application of 4-methoxyphenylethylamine according to claim 5 in lithium-ion battery electrolyte, characterized in that, The 4-methoxyphenylethylamine is added directly to the lithium-ion battery electrolyte.