Electrode, preparation method and application thereof, supercapacitor and energy storage characteristic optimization method thereof

Abstract

The invention discloses an electrode, a preparation method and application of the electrode, a super capacitor and an energy storage characteristic optimization method of the super capacitor, and relates to the technical field of super capacitors. The material has charge and discharge stability under an extreme test condition, and excellent conductivity of charge transmission is ensured; in addition, the electricity storage reaction capacity of the electrode material is improved in an in-situ electric activation mode, the electrochemical activity and the electrolyte penetration depth are remarkably improved, and therefore the effect of improving the energy storage characteristic of the supercapacitor is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of supercapacitors, and in particular to an electrode and a preparation method and application thereof, a supercapacitor and a method for optimizing its energy storage characteristics. Background Art

[0002] With the annual growth of clean energy power generation worldwide, commercial-grade organic supercapacitors, which usually have an energy storage density of less than 10Wh / kg, find it difficult to play a significant role in the field of new energy storage. It is urgent to develop supercapacitors with higher energy density to meet the growing needs of energy conversion, use, and distribution. This is also of great significance to promoting the balanced development of my country's inland and coastal areas.

[0003] The development of aqueous supercapacitors has gradually become an important way to develop high energy storage density supercapacitors. However, compared with commercial organic supercapacitors, the process of further improving the energy storage characteristics of the device through pre-electrochemical treatment is already very mature. However, there is still no widely used pretreatment method for aqueous supercapacitors, which to some extent affects the maximum efficiency that aqueous devices can achieve. Therefore, it is necessary to accelerate the research on the optimization of the structure and energy storage characteristics of commercial-grade high-energy density aqueous supercapacitors to provide new energy storage technologies with faster-charging chemical energy storage devices with higher energy density and more reliable safety performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an electrode and its preparation method and application, a supercapacitor and a method for optimizing its energy storage characteristics. On the one hand, the energy storage characteristics of the aqueous supercapacitor are improved by using the method of in-situ electrical activation of the electrode sheet. On the other hand, a unique electrode coating design is used to ensure that the active material of the electrode sheet maintains high stability under extreme test conditions, thereby enabling the in-situ electrical activation process of the electrode sheet to be quickly realized without destroying the supercapacitor electrode material. The resulting aqueous supercapacitor has the advantages of high specific capacitance, rate performance, and good charge and discharge cycle stability.

[0005] The technical problem to be solved by the present invention is achieved by adopting the following technical solutions:

[0006] One of the objects of the present invention is to provide a method for preparing an electrode, comprising the following steps:

[0007] (1) Using a carbon / pseudocapacitor composite material as an active material, mixing it with a conductive agent, a binder, and a solvent to obtain an electrode slurry 1;

[0008] Carbon material is used as an active material and mixed with a conductive agent, a binder and a solvent to obtain electrode slurry 2;

[0009] (2) coating the electrode slurry 1 on the surface of the current collector to form an active material layer on the current collector;

[0010] (3) The electrode slurry 2 is coated on the active material layer, dried, and rolled to obtain an electrode.

[0011] In the present invention, the carbon / pseudocapacitor composite material is composited from a carbon material and a pseudocapacitor material.

[0012] In the present invention, the carbon material is selected from one or more of activated carbon, graphene, graphite, carbon nanotubes, and carbon fibers.

[0013] Furthermore, the pseudocapacitive material is selected from one or more of metal oxides, metal nitrides, and conductive polymers.

[0014] Furthermore, the metal oxide includes but is not limited to one or more of manganese dioxide (MnO2), ferrosoferric oxide (Fe3O4), cobalt trioxide (Co3O4), manganese tetraoxide (Mn3O4), cuprous oxide (Cu2O), and zinc oxide (ZnO).

[0015] Furthermore, the composite methods of the carbon material and the pseudocapacitive material include the following two methods: one is to obtain a carbon / pseudocapacitive composite material by physically mixing the carbon material and the pseudocapacitive material; the other is to generate a carbon / pseudocapacitive composite material by laser induction from carbon and the precursor of the pseudocapacitive material.

[0016] Furthermore, the specific surface area of the carbon / metal oxide composite material is greater than 100m 2 / g.

[0017] Furthermore, the carbon content in the carbon / metal oxide composite material is 60-99 wt%.

[0018] Furthermore, the specific surface area of the carbon material is greater than 300m 2 / g.

[0019] In the present invention, the weight ratio of the active material to the conductive agent and the binder is (70-90):(2-20):(2-20).

[0020] In the present invention, the conductive agent includes but is not limited to one or more of acetylene black, conductive carbon black, graphite, Ketjen black, and carbon nanotubes; the binder includes but is not limited to one or more of polyvinylidene fluoride (PVDF), sodium carboxymethyl cellulose (CMC-Na), polytetrafluoroethylene (PTFE), styrene-butadiene rubber (SBR), and polyacrylate; the solvent includes but is not limited to one or more of N-methylpyrrolidone (NMP), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0021] In the present invention, the current collector includes but is not limited to one or more of aluminum foil, carbon-coated aluminum foil, copper foil, carbon-coated copper foil, stainless steel foil, carbon-coated stainless steel foil, nickel foil, and titanium foil.

[0022] Furthermore, the current collector has a thickness of 1 to 100 μm and a resistance of less than 0.2 Ω.

[0023] In the present invention, the coating is single-sided or double-sided coating, and the coating methods include but are not limited to one or more of scraping, spraying, rolling, and printing.

[0024] In the present invention, the coating thickness of the electrode slurry 1 is 50 to 1000 μm, preferably 200 to 700 μm; the coating thickness of the electrode slurry 2 is 10 to 500 μm, preferably 10 to 300 μm.

[0025] In the present invention, the drying method includes but is not limited to one or more of vacuum drying, air flow drying, microwave drying, freeze drying, and natural drying.

[0026] In the present invention, the roller pressing pressure is 1 to 500 MPa.

[0027] A second object of the present invention is to provide an electrode prepared by the aforementioned preparation method.

[0028] A third object of the present invention is to provide application of the aforementioned electrode in a supercapacitor.

[0029] A fourth object of the present invention is to provide a supercapacitor comprising a positive electrode, a negative electrode, a separator and an electrolyte, wherein the positive electrode and / or the negative electrode is the aforementioned electrode.

[0030] In the present invention, the membrane includes but is not limited to one or more of an inorganic composite membrane, a biomass-based membrane, and a synthetic polymer membrane.

[0031] In the present invention, the electrolyte is an aqueous electrolyte or an organic electrolyte.

[0032] Furthermore, the aqueous electrolyte includes but is not limited to one or more of sodium sulfate (Na2SO4), lithium chloride (LiCl), potassium chloride (KCl), sulfuric acid (H2SO4), and sodium hydroxide (KOH) solutions.

[0033] Furthermore, the organic electrolyte includes but is not limited to one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), and lithium trifluoromethanesulfonate (LiTFS) solutions.

[0034] Furthermore, the concentration of the electrolyte is 1-6M.

[0035] Furthermore, the charging and discharging operating current of the supercapacitor is 0.01 to 20A.

[0036] Furthermore, the supercapacitor includes an aqueous supercapacitor and an organic supercapacitor.

[0037] Furthermore, the limit operating voltage of the aqueous supercapacitor is 1.23-2.46V; the limit operating voltage of the organic supercapacitor is 2.7V.

[0038] A fifth object of the present invention is to provide a method for optimizing the energy storage characteristics of a supercapacitor, using a supercapacitor testing system to perform in-situ electrical activation treatment on a supercapacitor or an electrode of the aforementioned supercapacitor.

[0039] The beneficial effects of the present invention are:

[0040] (1) The present invention encapsulates a high-capacity carbon / metal oxide composite layer inside the electrode through a two-step electrode slurry coating process, so that the electrode has excellent energy storage characteristics and charge-discharge stability under extreme charge-discharge conditions, and ensures excellent conductivity for charge transfer, thereby maintaining a high degree of structural stability during electrical activation and causing minimal damage to the electrode as a whole.

[0041] (2) The present invention improves the storage reaction capacity of the electrode material by in-situ electrical activation, significantly improving the electrochemical activity and electrolyte penetration depth, thereby achieving the effect of improving the energy storage characteristics of the supercapacitor.

[0042] (3) The energy storage capacity and cycle stability of the supercapacitor treated by the energy storage characteristic optimization method provided by the present invention are simultaneously improved, providing a reference for the development of high energy density supercapacitors.

[0043] (4) The energy storage characteristics optimization method provided by the present invention has the advantages of simple operation, rapid implementation and low cost, and is expected to become a pretreatment method commonly used in commercial-grade water-based energy storage devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Schematic diagram of the electrical activation process of the symmetrical aqueous supercapacitor in Example 1;

[0045] Figure 2 Schematic diagram of the electrical activation process of the asymmetric aqueous supercapacitor in Example 2;

[0046] Figure 3 CP curves of the asymmetric aqueous supercapacitor in Example 2 before and after electrical activation treatment;

[0047] Figure 4CP curves of the asymmetric aqueous supercapacitor in Example 3 before and after electrical activation treatment;

[0048] Figure 5 Schematic diagram of the electrical activation process of the asymmetric aqueous supercapacitor in Example 4;

[0049] Figure 6 Schematic diagram of the electrical activation process of the asymmetric aqueous supercapacitor in Example 5;

[0050] Figure 7 This is a comparison chart of the cyclic charge-discharge stability of the asymmetric aqueous supercapacitor in Comparative Example 1 before and after electrical activation treatment;

[0051] Figure 8 This is a comparison chart of the application effect of the asymmetric aqueous supercapacitor in Comparative Example 1 on a 1.5V light bulb before and after electrical activation treatment;

[0052] Figure 9 This is a diagram of the electrical activation process of the asymmetric aqueous supercapacitor in Comparative Example 2. DETAILED DESCRIPTION

[0053] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below with reference to specific embodiments and illustrations.

[0054] Example 1

[0055] (1) Weigh 8 g of activated carbon / MnO2 composite material (obtained by physically mixing 6 g of activated carbon and 2 g of MnO2, with a carbon content of 75 wt% and a specific surface area of 500 m 2 / g) was mixed with 1 g of acetylene black, 1 g of PVDF and 50 mL of NMP, and stirred at a speed of 800 r / min for 8 h to obtain electrode slurry 1.

[0056] (2) Weigh 8.5 g of activated carbon material (specific surface area of 1000 m 2 / g) was mixed with 0.5g of acetylene black and 1.0g of polyvinylidene fluoride, and stirred at a speed of 800r / min for 8h to obtain electrode slurry 2.

[0057] (3) Electrode slurry 1 was coated on one side of a copper foil (10 μm thick) with a coating thickness of 800 μm to obtain an active material layer.

[0058] (4) Electrode slurry 2 was scraped onto the active material layer to a coating thickness of 50 μm, dried in a vacuum at 80°C, rolled twice at a pressure of 5 MPa and a speed of 50 r / min, and then cut into a size of 6 cm × 7 cm. A copper-nickel-plated steel strip (size of 1 cm × 3 cm) was connected to a stainless steel foil using an ultrasonic welder as a tab to obtain a pole piece.

[0059] (5) Using Na2SO4 solution (concentration of 1M) as the electrolyte, the electrodes and biomass-based diaphragms (Shanghai Kelude, model NKK-MPF30AC-100) were stacked layer by layer, and commercial aluminum-plastic film was used as the outer shell. After liquid injection, the electrodes were packaged in a vacuum environment to form a symmetrical aqueous supercapacitor.

[0060] (6) The symmetrical aqueous supercapacitor was electrically activated on a supercapacitor test system. It was first charged to 0.25 V at a working current of 252 mA, then charged to 0.5 V at a working current of 756 mA, then charged to 0.75 V at a working current of 1260 mA, then charged to 1.0 V at a working current of 1764 mA, and finally discharged to 0 V at a working current of 1260 mA. This cycle of charge and discharge was repeated 10 times.

[0061] Figure 1 Schematic diagram of the electro-activation process of the symmetrical aqueous supercapacitor in Example 1. Figure 1 It can be seen that the gradient charging process fully demonstrates the electrochemical reaction process of the capacitor's internal electrode materials, helping the electrodes to achieve their extreme energy storage properties. With increasing treatment times, the discharge time gradually increases from the 1st to 3rd cycles and gradually stabilizes from the 4th to 10th cycles, achieving the effect of enhancing the capacitor's specific capacity and stabilizing the capacitor's charge and discharge process, which can be used for subsequent electrochemical performance testing.

[0062] Example 2

[0063] (1) Weigh 8 g of activated carbon / MnO2 composite material (obtained by physically mixing 6 g of activated carbon and 2 g of MnO2, with a carbon content of 75 wt% and a specific surface area of 500 m 2 / g) was mixed with 1 g of acetylene black, 1 g of PVDF and 50 mL of NMP, and stirred at a speed of 800 r / min for 8 h to obtain electrode slurry 1.

[0064] (2) Weigh 8.5 g of activated carbon material (specific surface area of 1000 m 2 / g) was mixed with 0.5g of acetylene black and 1.0g of polyvinylidene fluoride, and stirred at a speed of 800r / min for 8h to obtain electrode slurry 2.

[0065] (3) Electrode slurry 1 was coated on both sides of a 316 stainless steel foil (10 μm thick) with a coating thickness of 800 μm to obtain an active material layer.

[0066] (4) Electrode slurry 2 was scraped onto the active material layer to a coating thickness of 50 μm, vacuum dried at 80°C, rolled twice at a pressure of 5 MPa and a speed of 50 r / min, and then cut into a size of 6 cm × 7 cm. A copper-nickel-plated steel strip (size of 1 cm × 3 cm) was connected to a stainless steel foil using an ultrasonic welder as a tab to obtain a positive electrode sheet.

[0067] (5) Weigh 8.5 g of activated carbon material (specific surface area of 2000 m 2 / g) was mixed with 0.5g of acetylene black and 1.0g of polyvinylidene fluoride, and stirred at a speed of 800r / min for 8h to obtain electrode slurry 3.

[0068] (6) Electrode slurry 3 was scraped onto copper foil (thickness of 10 μm) on both sides to a thickness of 1000 μm, dried in a vacuum at 80°C, rolled twice at a pressure of 5 MPa and a speed of 50 r / min, and then cut into a size of 6 cm × 7 cm. A copper-nickel-plated steel strip (size of 1 cm × 3 cm) was connected to the copper foil using an ultrasonic welder as a tab to obtain a negative electrode sheet.

[0069] (7) Using Na2SO4 solution (concentration of 1 M) as the electrolyte, 4 positive and negative electrode sheets were stacked layer by layer with a biomass-based diaphragm (Shanghai Kelude, model NKK-MPF30AC-100), and a commercial aluminum-plastic film was used as the outer shell. After liquid injection, the sheets were packaged in a vacuum environment to form an asymmetric aqueous supercapacitor.

[0070] (8) The asymmetric aqueous supercapacitor was electrically activated on a supercapacitor test system. It was first charged to 0.5 V at a working current of 252 mA, then charged to 1.0 V at a working current of 756 mA, then charged to 1.5 V at a working current of 1260 mA, then charged to 2.0 V at a working current of 1764 mA, and finally discharged to 0 V at a working current of 1260 mA. This cycle of charge and discharge was repeated 10 times.

[0071] Figure 2 : This is a diagram of the electro-activation process of the asymmetric aqueous supercapacitor in Example 2. Figure 2 It can be seen that during the 20 repeated electrical activation treatments, the gradient charging curve and discharge curve of the capacitor remained stable, and the time of the charging and discharging process gradually extended, indicating that the internal electrochemical reaction gradually reached saturation.

[0072] Figure 3 CP curves of the asymmetric aqueous supercapacitor in Example 2 before and after electro-activation treatment. Figure 3It can be seen that within the operating voltage range of 0 to 1.8 V, the discharge time of the capacitor increases from 421 s to 706 s, which means that the specific capacity of the capacitor increases by about 1.7 times, proving that the capacitor after electroactivation treatment has better electrochemical performance.

[0073] Example 3

[0074] The only difference between Example 3 and Example 2 is that 8 positive electrode sheets and 8 negative electrode sheets are stacked layer by layer with a biomass-based separator (Shanghai Kelude, model NKK-MPF30AC-100) to obtain a multi-layer asymmetric aqueous supercapacitor.

[0075] Figure 4 CP curves of the asymmetric aqueous supercapacitor in Example 3 before and after electro-activation treatment. Figure 4 It can be seen that within the operating voltage range of 0 to 1.8 V, the discharge time is also enhanced after electrical activation treatment, increasing from 1564 s to 1689 s, achieving the effect of optimizing the energy storage process. This proves the universality of the energy storage characteristic optimization method provided by the present invention in multi-layer soft-package devices and is expected to become one of the pretreatment methods commonly used in commercial aqueous energy storage devices.

[0076] Example 4

[0077] The only difference between Example 4 and Example 2 is that the activated carbon material in the preparation of electrode slurry 3 is replaced by a graphene / Co3O4 composite material (obtained by physically mixing 7g of graphene with 1g of Co3O4, with a carbon content of 87wt% and a specific surface area of 450m 2 / g).

[0078] Figure 5 4 is a diagram of the electro-activation process of the asymmetric aqueous supercapacitor in Example 4. Figure 5 It can be seen that, consistent with the effects of other embodiments, as the number of treatments increases, the discharge time is extended, and the change gradually slows down after the 8th treatment, indicating that the treatment process of the capacitor makes its charging and discharging process tend to be stable.

[0079] Example 5

[0080] The only difference between Example 5 and Example 2 is that the activated carbon material in the preparation of electrode slurry 3 is replaced by a graphene / Fe3O4 composite material (obtained by physically mixing 7g of graphene with 1g of Fe3O4, with a carbon content of 87wt% and a specific surface area of 400m 2 / g).

[0081] Figure 6 : This is a diagram of the electro-activation process of the asymmetric aqueous supercapacitor in Example 5. Figure 6It can be seen that the discharge time of the supercapacitor is significantly improved as the treatment progresses, indicating that the electrochemical storage reaction process of the asymmetric supercapacitor is gradually activated. At the same time, compared with the treatment effects of Examples 1 and 2, the discharge time improvement effect of Example 5 is more obvious than that of Example 4. During the 10 cycles of electroactivation treatment, the specific capacity can be increased by about 1.5 times. This proves that the energy storage characteristic optimization method provided by the present invention is one of the important ways to significantly realize the performance advantages of aqueous supercapacitors with pseudocapacitive energy storage characteristics.

[0082] Comparative Example 1

[0083] The only difference between Comparative Example 1 and Example 2 is that the asymmetric aqueous supercapacitor is not subjected to electrical activation treatment.

[0084] Figure 7 This is a comparison chart of the cyclic charge and discharge stability of the asymmetric aqueous supercapacitor in Comparative Example 1 before and after electrical activation treatment. Figure 7 It can be seen that within the range of 2000 cycles, the capacity retention rate of the untreated sample showed an obvious upward fluctuation in the 1st to 200th cycle charge and discharge range, indicating that the contact between the electrolyte and the electrode material slowly improved, while the curve of the treated aqueous supercapacitor remained stable within 2000 charge and discharge cycles, proving that the treated device can exert a more stable electrochemical storage reaction.

[0085] Figure 8 This is a comparison chart of the application effect of the asymmetric aqueous supercapacitor in comparative example 1 on a 1.5V light bulb before and after electrical activation treatment. Figure 8 It can be seen that the capacitor after electrical activation treatment can make the small light bulb brighter within the same discharge time, which means that it has higher capacitance and better energy storage characteristics.

[0086] Comparative Example 2

[0087] The only difference between Comparative Example 2 and Example 2 is that the active material layer is not encapsulated and protected, that is, electrode slurry 1 is only scraped on both sides of the 316 stainless steel foil surface, and electrode slurry 2 is not scraped on the active material layer.

[0088] Figure 9 FIG2 is a diagram of the electro-activation process of the asymmetric aqueous supercapacitor in comparative example 2. Figure 9 It can be seen that the first-cycle activation process of the capacitor is hindered, and it is difficult to reach the set charging voltage platform under the same charging current. This is due to the lack of encapsulation of the external carbon material layer. The overall conductivity of the electrode is reduced, resulting in its charging and discharging capabilities in extreme environments. Reduced, which has a certain impact on the subsequent cycle stability.

[0089] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an electrode, characterized in that: The preparation method comprises the following steps: (1) Using a carbon / pseudocapacitor composite material as an active material, mixing it with a conductive agent, a binder, and a solvent to obtain an electrode slurry 1; Carbon material is used as an active material and mixed with a conductive agent, a binder and a solvent to obtain electrode slurry 2; (2) coating the electrode slurry 1 on the surface of the current collector to form an active material layer on the current collector; (3) The electrode slurry 2 is coated on the active material layer, dried, and rolled to obtain an electrode.

2. The preparation method according to claim 1, wherein: The carbon / pseudocapacitor composite material is composed of a carbon material and a pseudocapacitor material; Preferably, the carbon material is selected from one or more of activated carbon, graphene, graphite, carbon nanotubes, and carbon fibers; Preferably, the pseudocapacitive material is selected from one or more of metal oxides, metal nitrides, and conductive polymers; Preferably, the metal oxide is selected from one or more of manganese dioxide, ferrosoferric oxide, cobalt trioxide, manganese tetraoxide, cuprous oxide, and zinc oxide; Preferably, the composite method of the carbon material and the pseudocapacitive material includes the following two methods: one is to obtain a carbon / pseudocapacitive composite material by physically mixing the carbon material and the pseudocapacitive material; the other is to generate a carbon / pseudocapacitive composite material by laser induction from carbon and a precursor of the pseudocapacitive material; Preferably, the specific surface area of the carbon / metal oxide composite material is greater than 100 m 2 / g; Preferably, the carbon content in the carbon / metal oxide composite material is 60 to 99 wt%; Preferably, the specific surface area of the carbon material is greater than 300 m 2 / g.

3. The preparation method according to claim 1, wherein: The weight ratio of the active material to the conductive agent and the binder is (70-90):(2-20):(2-20); Preferably, the conductive agent is selected from one or more of acetylene black, conductive carbon black, graphite, Ketjen black, and carbon nanotubes; Preferably, the binder is selected from one or more of polyvinylidene fluoride, sodium carboxymethyl cellulose, polytetrafluoroethylene, styrene-butadiene rubber, and polyacrylate; Preferably, the solvent is selected from one or more of N-methylpyrrolidone, dimethylformamide, and dimethyl sulfoxide.

4. The preparation method according to claim 1, wherein: The current collector is selected from one or more of aluminum foil, carbon-coated aluminum foil, copper foil, carbon-coated copper foil, stainless steel foil, carbon-coated stainless steel foil, nickel foil, and titanium foil; Preferably, the thickness of the current collector is 1 to 100 μm, and the resistance is less than 0.2Ω; Preferably, the coating is single-sided or double-sided coating, selected from one or more of scraping, spraying, rolling, and printing; Preferably, the coating thickness of the electrode slurry 1 is 50 to 1000 μm, more preferably 200 to 700 μm; Preferably, the coating thickness of the electrode slurry 2 is 10 to 500 μm, more preferably 10 to 300 μm; Preferably, the drying method is selected from one or more of vacuum drying, air flow drying, microwave drying, freeze drying, and natural drying; Preferably, the roller pressing pressure is 1-500 MPa.

5. An electrode prepared by the preparation method according to any one of claims 1 to 4.

6. Use of the electrode according to claim 5 in a supercapacitor.

7. A supercapacitor comprising a positive electrode, a negative electrode, a separator and an electrolyte, characterized in that: The positive electrode and / or negative electrode is the electrode according to claim 5.

8. The supercapacitor according to claim 7, wherein: The diaphragm is selected from one or more of an inorganic composite diaphragm, a biomass-based diaphragm, and a synthetic polymer diaphragm; Preferably, the electrolyte is an aqueous electrolyte or an organic electrolyte; Preferably, the aqueous electrolyte is selected from one or more of sodium sulfate, lithium chloride, potassium chloride, sulfuric acid, and sodium hydroxide solution. Preferably, the organic electrolyte includes but is not limited to one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, and lithium trifluoromethanesulfonate solutions; Preferably, the concentration of the electrolyte is 1-6M.

9. The supercapacitor according to claim 7, wherein: The charging and discharging operating current of the supercapacitor is 0.01 to 20A; Preferably, the supercapacitor includes an aqueous supercapacitor and an organic supercapacitor; Preferably, the maximum operating voltage of the aqueous supercapacitor is 1.23-2.46V; the maximum operating voltage of the organic supercapacitor is 2.7V.

10. A method for optimizing the energy storage characteristics of a supercapacitor, comprising performing in-situ electrical activation treatment on a supercapacitor or an electrode of the supercapacitor according to any one of claims 7 to 9 using a supercapacitor testing system.

Images