Electrolyte for reducing internal temperature rise of capacitor

Abstract

The invention relates to the technical field of electrolytes, in particular to an electrolyte for reducing internal temperature rise of a capacitor, which comprises the following components in percentage by mass: 40-60% of solvent, 30-50% of salt, 1-10% of additive and 1-10% of electrolyte. The solvent is dimethyl carbonate and methanol. The electrolyte with the acrylonitrile acrylate copolymer as the main material has high thermal stability, the structural stability and functionality of the electrolyte can be kept in a high-temperature environment, and the electrolyte can be influenced by high temperature in the working process of the capacitor, so that if the electrolyte does not have enough thermal stability, the electrolyte can be prevented from being influenced by high temperature. And due to the addition of the acrylonitrile acrylate copolymer, the thermal stability of the electrolyte can be enhanced, and the influence of internal temperature rise on the capacitor can be effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of electrolytes, and in particular to an electrolyte capable of reducing the internal temperature rise of a capacitor. Background Art

[0002] With the advancement of science and technology, the growing demand for portable power in mobile electronic devices, electric vehicles and the Internet of Things has promoted extensive research on reversible and efficient electrochemical energy storage devices. Battery materials can store large amounts of energy through diffusion-controlled redox reactions at low power densities, with a slow charging process of about several hours.

[0003] Capacitive materials store much lower energy density through the double-layer mechanism, with a fast charging process of about a few seconds and ultra-high power density; electrochemical capacitors have received great attention in academia and industry due to their ultra-high power density, fast charging rate and ultra-long cycle life. At present, capacitors often suffer from performance degradation and shortened life in high-power applications due to excessive internal temperature rise. Therefore, it is urgent to find an electrolyte that can reduce the internal temperature rise of the capacitor. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides an electrolyte for reducing the internal temperature rise of the capacitor, which can effectively solve the problem of performance degradation and shortened life due to excessive internal temperature rise in the prior art.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: The present invention provides an electrolyte for reducing the temperature rise inside a capacitor, comprising a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 40% to 60%, 30% to 50%, 1% to 10% and 1% to 10% respectively; The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is one of 7:3 and 8:2; The electrolyte is acrylonitrile acrylate copolymer.

[0006] According to the above-mentioned electrolyte for reducing the internal temperature rise of a capacitor, the mass percentages of the solvent, salts, additives and electrolyte are 50%, 40%, 5% and 5% respectively.

[0007] According to the above-mentioned electrolyte for reducing the internal temperature rise of a capacitor, the mass percentages of the solvent, salts, additives and electrolyte are 55%, 35%, 6% and 4% respectively.

[0008] According to the above-mentioned electrolyte for reducing the internal temperature rise of a capacitor, the mass percentages of the solvent, salts, additives and electrolyte are 45%, 40%, 7% and 8% respectively.

[0009] According to the above-mentioned electrolyte for reducing the temperature rise inside the capacitor, the salt is at least one of ammonium sulfate and sodium bisulfate.

[0010] According to the above-mentioned electrolyte for reducing the temperature rise inside the capacitor, the additive is at least one of polyethyleneimine, trimethyl phosphate, and nano-aluminum oxide.

[0011] According to the above-mentioned electrolyte for reducing the temperature rise inside the capacitor, the preparation method includes: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2 as raw materials into a reaction container, and stirring for 45 min to 55 min to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 45 minutes to 55 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0012] Compared with the known prior art, the technical solution provided by the present invention has the following beneficial effects: 1. By setting dimethyl carbonate as the main solvent component, it has a higher flash point and lower volatility, which can reduce the evaporation and heat loss of the solvent in the capacitor. It is also beneficial to many electrochemical reactions and electrolyte stability, effectively improving the cycle life and performance stability of the capacitor; 2. By setting alcohol as the auxiliary solvent component, it has lower viscosity and higher conductivity, which can improve the ion conductivity of the electrolyte, and can also effectively reduce the internal resistance of the electrolyte, reduce the internal energy loss of the capacitor, and promote some electrochemical reactions. By using a mixed solvent of dimethyl carbonate and methanol as the electrolyte solvent, a stable electrolyte environment can be provided, reducing the temperature rise inside the capacitor; 3. By setting the electrolyte whose main material is acrylonitrile acrylate copolymer, it has high thermal stability and can maintain its structural stability and functionality in a high temperature environment. Because during the operation of the capacitor, the electrolyte may be affected by high temperature. If the electrolyte does not have sufficient thermal stability, it may cause the capacitor to deteriorate in performance or fail. The addition of acrylonitrile acrylate copolymer can enhance the thermal stability of the electrolyte and effectively reduce the impact of internal temperature rise on the capacitor. 4. By setting the additives whose raw materials are a mixture of polyethyleneimine and trimethyl phosphate, the stability of the electrolyte is promoted to a certain extent. They can interact with the electrolyte molecules to form a stable structure, which can prevent the decomposition or adverse reactions of the electrolyte molecules, thereby helping to maintain the good state of the electrolyte inside the capacitor and reducing the adverse effects of temperature rise on the performance of the capacitor. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0014] The present invention will be further described below in conjunction with the embodiments.

[0015] Embodiment 1: An electrolyte for reducing the internal temperature rise of a capacitor, comprising a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 50%, 40%, 5% and 5% respectively; The solvents are dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is 8:2. Dimethyl carbonate, as the main solvent component, has a higher flash point and lower volatility, which can reduce the evaporation and heat loss of the solvent in the capacitor, and is also beneficial to many electrochemical reactions and electrolyte stability, effectively improving the cycle life and performance stability of the capacitor. Methanol, as an auxiliary solvent component, has lower viscosity and higher conductivity, which can improve the ion conductivity of the electrolyte, and can also effectively reduce the internal resistance of the electrolyte, reduce the internal energy loss of the capacitor, and promote some electrochemical reactions. By using a mixed solvent of dimethyl carbonate and methanol as the electrolyte solvent, a stable electrolyte environment can be provided and the temperature rise inside the capacitor can be reduced.

[0016] The electrolyte is acrylonitrile acrylate copolymer, which has high thermal stability and can maintain its structural stability and functionality in a high temperature environment. During the operation of the capacitor, the electrolyte may be affected by high temperature. If the electrolyte does not have sufficient thermal stability, it may cause the capacitor to perform poorly or fail. The addition of acrylonitrile acrylate copolymer can enhance the thermal stability of the electrolyte and effectively reduce the impact of internal temperature rise on the capacitor.

[0017] The salt is ammonium sulfate, which is added to the electrolyte as a salt to increase the solubility of other components in the solution. This helps to maintain the uniformity and stability of the electrolyte, reduce local concentration differences, and thus reduce the uneven distribution of temperature rise.

[0018] The additive is a mixture of polyethyleneimine and trimethyl phosphate, which has a certain promoting effect on the stability of the electrolyte. They can interact with the electrolyte molecules to form a stable structure to prevent the decomposition or adverse reactions of the electrolyte molecules, thereby helping to maintain the good state of the electrolyte inside the capacitor and reduce the adverse effects of temperature rise on the capacitor performance.

[0019] The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2 as raw materials into a reaction container, and stirring for 55 minutes to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 55 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0020] Embodiment 2: An electrolyte for reducing the internal temperature rise of a capacitor, comprising a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 55%, 35%, 6% and 4% respectively; The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is 7:3; The electrolyte is acrylonitrile acrylate copolymer.

[0021] The salt is sodium bisulfate. Sodium bisulfate is added to the electrolyte as a salt. It can effectively reduce the temperature rise inside the capacitor by providing ions, adjusting pH value, enhancing solubility and improving electrolyte stability, thereby improving the performance stability and service life of the capacitor.

[0022] The additive is a mixture of trimethyl phosphate and nano-aluminum oxide, which can effectively reduce the temperature rise inside the capacitor and improve the performance stability and reliability of the capacitor by enhancing thermal conductivity, improving electrolyte stability, reducing electrolyte loss, improving safety and reducing insulation loss.

[0023] The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2, into a reaction vessel, and stirring for 52 minutes to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 52 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0024] Embodiment three: An electrolyte for reducing the internal temperature rise of a capacitor comprises a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 45%, 40%, 7% and 8% respectively.

[0025] The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is 8:2; The electrolyte is acrylonitrile acrylate copolymer.

[0026] The salt is a mixture of ammonium sulfate and sodium bisulfate. Proper adjustment of the pH value helps to optimize the chemical environment inside the capacitor, improve its stability and performance, reduce unnecessary chemical reactions, and thus reduce temperature rise.

[0027] The additive is a mixture of polyethyleneimine and nano-alumina, which can reduce the risk of fire in the event of a malfunction or abnormal condition of the capacitor. This is particularly important for improving the safety of capacitors, especially in high-power or long-term working conditions.

[0028] The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2, into a reaction vessel, and stirring for 45 minutes to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 45 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0029] Embodiment 4: An electrolyte for reducing the internal temperature rise of a capacitor, comprising a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 53%, 36%, 6% and 5% respectively; The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is 8:2; The electrolyte is acrylonitrile acrylate copolymer.

[0030] The salt is sodium bisulfate. Sodium bisulfate is added to the electrolyte as a salt. It can effectively reduce the temperature rise inside the capacitor by providing ions, adjusting pH value, enhancing solubility and improving electrolyte stability, thereby improving the performance stability and service life of the capacitor.

[0031] The additive is trimethyl phosphate, which can effectively reduce the temperature rise inside the capacitor and improve the performance stability and reliability of the capacitor by enhancing electrolyte stability, reducing electrolyte loss, improving safety, reducing insulation loss and improving the fluidity of the electrolyte.

[0032] The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2, into a reaction vessel, and stirring for 48 minutes to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 48 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0033] Embodiment five: An electrolyte for reducing the internal temperature rise of a capacitor, comprising a solvent, a salt, an additive and an electrolyte, wherein the mass percentages of the solvent, the salt, the additive and the electrolyte are 52%, 38%, 4% and 6% respectively; The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate to methanol is 7:3; The electrolyte is acrylonitrile acrylate copolymer.

[0034] The salt is sodium bisulfate.

[0035] The additive is nano-aluminum oxide, which can effectively reduce the temperature rise inside the capacitor and improve the performance stability and reliability of the capacitor by increasing thermal conductivity, improving fluidity, inhibiting bubble generation, enhancing electrolyte stability and improving safety.

[0036] The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2, into a reaction vessel, and stirring for 50 min to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 50 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electrolyte for reducing the temperature rise inside a capacitor, characterized in that: It includes solvents, salts, additives and electrolytes, wherein the mass percentages of the solvents, salts, additives and electrolytes are 40% to 60%, 30% to 50%, 1% to 10% and 1% to 10% respectively; The solvent is dimethyl carbonate and methanol, and the ratio of dimethyl carbonate and methanol is 7:3, 8:2 in one; The electrolyte is acrylonitrile acrylate copolymer.

2. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The mass percentages of the solvent, salts, additives and electrolyte are 50%, 40%, 5% and 5% respectively.

3. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The mass percentages of the solvent, salts, additives and electrolyte are 55%, 35%, 6% and 4% respectively.

4. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The mass percentages of the solvent, salts, additives and electrolyte are 45%, 40%, 7% and 8% respectively.

5. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The salt is at least one of ammonium sulfate and sodium bisulfate.

6. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The additive is at least one of polyethyleneimine, trimethyl phosphate and nano-alumina.

7. The electrolyte for reducing the temperature rise inside a capacitor according to claim 1, characterized in that: The preparation method comprises: S1, adding the solvent, i.e., dimethyl carbonate and methanol in a ratio of 8:2 as raw materials into a reaction container, and stirring for 45 min to 55 min to obtain a solvent mixture; S2, adding salts, additives and electrolytes to the solvent mixture obtained in S1 in sequence, and continuing stirring for 45 minutes to 55 minutes to obtain an electrolyte to be treated; S3, filtering the electrolyte to be treated obtained in S2 to remove impurities and fixed particles therein, and finally obtaining the desired electrolyte.