WO2022143262A1

WO2022143262A1 - Energy storage device

Info

Publication number: WO2022143262A1
Application number: PCT/CN2021/139718
Authority: WO
Inventors: 范鑫铭; 蔡伟平; 陈志勇
Original assignee: 广东微电新能源有限公司
Priority date: 2020-12-31
Filing date: 2021-12-20
Publication date: 2022-07-07
Also published as: CN112713301A; CN112713301B

Abstract

An energy storage device, comprising a positive electrode sheet, a negative electrode sheet, a gel polymer electrolyte membrane and an ether-based electrolyte. The gel polymer electrolyte membrane is arranged between the positive electrode sheet and the negative electrode sheet. The ether-based electrolyte is filled between the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane. The components of the ether-based electrolyte comprise: lithium bis(trifluoromethanesulfonyl)imide, 1,2-dimethoxyethane and 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoro propane ether.

Description

energy storage device

The present disclosure claims the priority of a Chinese patent application with application number 202011639493.5 and titled “Energy Storage Device” filed with the China Patent Office on December 31, 2020, the entire contents of which are incorporated in this disclosure by reference.

technical field

The present disclosure relates to the technical field of batteries, and more particularly, to an energy storage device.

Background technique

At present, electronic products mainly rely on batteries to provide electrical energy. With the update and development of electronic products, batteries also need to adapt to different electronic products. In the case of using electronic products for a long time, the electrode materials in the battery participate in the reaction for a long time, and the electrode materials will be depleted too quickly, and the battery capacity will be irreversibly attenuated.

In the prior art, the electrolyte and electrode materials in the battery are prone to side reactions during the charging and discharging process, resulting in irreversible attenuation of the battery capacity.

Therefore, a new technical solution is required to solve the above technical problems.

SUMMARY OF THE INVENTION

An object of the present disclosure is to provide a new technical solution for an energy storage device.

According to a first aspect of the present disclosure, an energy storage device is provided, the energy storage device comprising a positive electrode sheet, a negative electrode sheet, a gel polymer electrolyte membrane and an ether-based electrolyte;

The gel polymer electrolyte membrane is arranged between the positive electrode sheet and the negative electrode sheet, and the ether-based electrolyte is filled between the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane ;

The components of the ether-based electrolyte include: lithium bisfluorosulfonimide, 1,2-dimethoxyethane and 1,1,2,2-

tetrafluoroethyl

2,2,3,3- Tetrafluoropropane ether.

Optionally, the lithium bisfluorosulfonimide, the 1,2-dimethoxyethane and the 1,1,2,2-

tetrafluoroethyl

2,2,3,3-tetrafluoroethylene The molar ratio of fluoropropane ether is 0.5-1.5:0.5-1.5:3.

Optionally, the gel polymer electrolyte membrane includes polyvinyl alcohol-lithium sulfate and/or polyvinyl alcohol-lithium nitrate.

Optionally, the thickness of the gel polymer electrolyte membrane is 10 μm-50 μm.

Optionally, the negative electrode sheet includes a negative electrode current collector and a negative electrode material coated on the negative electrode current collector, and the negative electrode material includes polypyrrole-lithium vanadate and/or polypyrrole-lithium titanate.

Optionally, the negative electrode material further includes a conductive agent and a binder, and the conductive agent and the binder are mixed with the polypyrrole-lithium vanadate and/or the polypyrrole-lithium titanate .

Optionally, the positive electrode sheet includes a positive electrode current collector and a positive electrode material coated on the positive electrode current collector, and the positive electrode material includes lithium cobalt oxide, lithium manganate, lithium nickel manganate, lithium nickel cobalt manganate or Lithium-rich manganese.

Optionally, the positive electrode material further includes a conductive agent and a binder, and the conductive agent and the binder are combined with the lithium cobaltate, the lithium manganate, the lithium nickel manganate, the nickel Lithium cobalt manganate or lithium rich manganese mixed together.

Optionally, it includes a plurality of the positive electrode sheets, a plurality of the negative electrode sheets and a plurality of gel polymer electrolyte membranes, the plurality of positive electrode sheets and the plurality of negative electrode sheets are alternately and stacked, and the adjacent ones The gel polymer electrolyte membrane is arranged between the positive electrode sheet and the negative electrode sheet to form a laminated structure.

Optionally, the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane are stacked and arranged to form a winding structure.

In one embodiment of the present disclosure, through the interaction between the gel polymer electrolyte membrane and the ether-based electrolyte, the wettability of the gel polymer electrolyte can be improved, the ionic conductivity can be improved, and the rate capability of the energy storage device can be improved. .

Other features of the present disclosure and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1 is a schematic structural diagram of an energy storage device in an embodiment of the present disclosure.

FIG. 2 is a discharge capacity diagram of an energy storage device in an embodiment of the present disclosure under different charge and discharge rates.

FIG. 3 is a graph of the capacitance change of the energy storage device in an embodiment of the present disclosure when cycled at a current density of 2C.

Detailed ways

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the disclosure, its application or uses in any way.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

In all examples shown and discussed herein, any specific values should be construed as illustrative only and not limiting. Accordingly, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further discussion in subsequent figures.

According to an embodiment of the present disclosure, an energy storage device is provided. As shown in FIG. 1 , the energy storage device includes a positive electrode sheet 21 , a negative electrode sheet 22 , a gel polymer electrolyte membrane 23 and an ether-based electrolyte 3 .

The gel polymer electrolyte membrane 23 is arranged between the positive electrode sheet 21 and the negative electrode sheet 22, and the ether-based electrolyte 3 is filled in the positive electrode sheet 21, the negative electrode sheet 22 and the gel between the polymer electrolyte membranes 23 .

The components of the ether-based electrolyte include: lithium bisfluorosulfonimide (LiFSI), 1,2-dimethoxyethane (DME) and 1,1,2,2-

tetrafluoroethyl

2, 2,3,3-Tetrafluoropropane ether (TTE).

The housing 1 of the energy storage device has an accommodating cavity, and the battery cells 2 are arranged in the accommodating cavity. The positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane form the structure of the battery cell 2 . The ether-based electrolyte is filled between the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane, so that the battery core 2 is in the ether-based electrolyte.

In this embodiment, the cell 2 is in the ether-based electrolyte, so that the electrolyte wraps the cell 2 . The gel polymer electrolyte membrane acts as a separator between the positive electrode sheet and the negative electrode sheet, and can selectively pass ions. Gel polymer electrolyte membranes are thin films formed by gel polymer dielectric preparation.

The ether-based electrolyte contains lithium bisfluorosulfonimide, 1,2-dimethoxyethane and 1,1,2,2-

tetrafluoroethyl

2,2,3,3-tetrafluoropropane ether , the ether-based electrolyte can improve the wettability of the gel polymer electrolyte, so as to improve the electrical conductivity of the ions in the energy storage device, thereby improving the rate performance of the energy storage device. That is, the charge-discharge capacity of the energy storage device is improved under the action of the gel polymer electrolyte membrane and the ether-based electrolyte in this embodiment.

In one embodiment, the lithium bisfluorosulfonimide, the 1,2-dimethoxyethane, and the 1,1,2,2-

tetrafluoroethyl

2,2,3,3 - The molar ratio of tetrafluoropropane ether is 0.5-1.5:0.5-1.5:3.

The different proportions of components in the ether-based electrolyte make the ether-based electrolyte have completely different effects on improving the battery capacity in energy storage devices, especially on the wettability of the gel polymer electrolyte.

In this example, lithium bisfluorosulfonimide, the 1,2-dimethoxyethane, and the 1,1,2,2-

tetrafluoroethyl

2,2,3,3-tetra The molar ratio of fluoropropane ether effectively improves the wettability of the gel polymer electrolyte (GPE), effectively increases the electrical conductivity of ions in the electrolyte, and further increases the rate capability of the electrical capacity of the energy storage device. improve.

In one embodiment, the gel polymer electrolyte membrane includes polyvinyl alcohol-lithium sulfate (PVA-Li ₂ SO ₄ ) and/or polyvinyl alcohol-lithium nitrate (PVA-LiNO ₃ ).

The gel polymer electrolyte membrane is a membrane layer formed by a gel polymer electrolyte, and the gel polymer electrolyte membrane is arranged on the positive electrode sheet and the negative electrode sheet as the electrolyte layer of the energy storage device. Gel polymer electrolytes are materials whose states are intermediate between solid electrolytes and liquid electrolytes, and have the advantages of high electrical conductivity, electrochemical stability, high mechanical strength, and high lithium ion migration numbers.

The gel polymer electrolyte membrane can adapt to the structure of different forms of energy storage devices, and the gel polymer electrolyte membrane has excellent structural processability, which can improve the flexibility of energy storage device design in accordance with the structural requirements of energy storage devices.

The gel polymer electrolyte membrane can be formed by different molding methods, so that the gel polymer electrolyte membrane can exhibit different structural characteristics, so that it is easier to confine the ether-based electrolyte in the structure of the gel polymer electrolyte membrane, which promotes the The interaction between the gel polymer electrolyte membrane and the ether-based electrolyte further improves the wettability of the gel polymer electrolyte.

In one embodiment, the thickness of the gel polymer electrolyte membrane is 10 μm-50 μm.

A gel polymer electrolyte membrane with a thickness of 10 μm-50 μm is formed by pressing the gel polymer electrolyte, so as to be more easily arranged on the positive electrode sheet and the negative electrode sheet. For example, a gel polymer electrolyte membrane is attached to the positive electrode sheet and the negative electrode sheet. The gel polymer electrolyte membrane and the ether-based electrolyte enable the positive electrode sheet and the negative electrode sheet to fully participate in the reaction, and the gel polymer electrolyte membrane further improves the conductivity of ions in the electrolyte under the action of the ether-based electrolyte. For example, the conductivity of lithium ions in the electrolyte is increased.

In the thickness range of 10 μm-50 μm, the gel polymer electrolyte membrane can effectively exchange ions between the positive electrode sheet and the negative electrode sheet, so as to satisfy the function of the electrolyte charge-discharge reaction.

Within this thickness range, the gel polymer electrolyte membrane does not occupy too much space, so that the battery cell can be provided with more positive electrode sheets and negative electrode sheets under a limited volume.

In one embodiment, the negative electrode sheet includes a negative electrode current collector and a negative electrode material coated on the negative electrode current collector, and the negative electrode material includes polypyrrole-lithium vanadate (PPy-LVO) and/or polypyrrole- Lithium Titanate (PPy-LTO).

In this embodiment, the negative electrode material includes polypyrrole-lithium vanadate and/or polypyrrole-lithium titanate, and the negative electrode material has better stability. The phenomenon of dissolution and deposition of the electrode during the reaction process is reduced, and the damage to the electrode is effectively reduced, so as to avoid piercing or forming holes on the electric core. The negative electrode material effectively avoids the safety problem caused by the short circuit between the positive electrode sheet and the negative electrode sheet.

For example, a polypyrrole layer is formed on the surface of the lithium vanadate material to obtain a polypyrrole-lithium vanadate material. Alternatively, a polypyrrole layer is formed on the surface of the lithium titanate material to obtain a polypyrrole-lithium titanate material.

The polypyrrole material forms a conductive coating, which improves the stability of the material. The negative electrode material is more stable in the electrolyte, which effectively reduces the consumption and damage to the negative electrode material during the reaction process of the energy storage device, and reduces the short circuit between the negative electrode and the positive electrode of the energy storage device due to the formation of dendrites piercing the isolation layer and the positive electrode of the energy storage device. safety of the device.

In one embodiment, the negative electrode material further includes a conductive agent and a binder, and the conductive agent and the binder are mixed with the polypyrrole-lithium vanadate and/or the polypyrrole-lithium titanate together.

In this embodiment, setting the negative electrode material requires mixing a conductive agent and a binder with polypyrrole-lithium vanadate and/or polypyrrole-lithium titanate in a deionized water solvent to form a slurry.

The negative electrode sheet is formed by coating the negative electrode material on the negative electrode current collector. The negative electrode material is a slurry, and the slurry is coated on the negative electrode current collector, and the slurry needs to be solidified to form a negative electrode sheet. For example, moisture is evaporated by drying to solidify the slurry on the negative electrode current collector. The solidified slurry and the negative electrode current collector are solidified to form an integrated structure.

For example, the conductive agent, the binder, and the polypyrrole-lithium vanadate and/or the polypyrrole-lithium titanate are uniformly mixed in a deionized water solvent to form a slurry. The binder in the slurry makes the materials in the negative electrode material bond together more firmly, and makes the slurry bond with the negative electrode current collector more easily. The conductive agent can improve the conductive effect of the negative electrode sheet.

For example, the negative electrode current collector is a copper foil, and the slurry made of the negative electrode material is coated on the copper foil, and processed to form a negative electrode sheet.

Alternatively, the conductive agent may be conductive carbon black, acetylene black, carbon nanotubes, and the like. The adhesive may be styrene butadiene rubber (SBR).

In one embodiment, the positive electrode sheet includes a positive electrode current collector and a positive electrode material coated on the positive electrode current collector, and the positive electrode material includes lithium cobalt oxide, lithium manganate, lithium nickel manganate, nickel cobalt manganate Lithium or Li-rich Manganese.

In this embodiment, the positive electrode sheet is formed by coating the positive electrode material on the positive electrode current collector. For example, the positive electrode current collector is an aluminum foil, and the aluminum foil is coated with lithium cobalt oxide, lithium manganate, lithium nickel manganate, lithium nickel cobalt manganate, or lithium-rich manganese to form a positive electrode sheet. Lithium cobalt oxide, lithium manganate, lithium nickel manganese oxide, lithium nickel cobalt manganate, or lithium-rich manganese as cathode materials can effectively provide lithium ions to participate in the reaction, reduce the consumption of cathode current collectors, and improve the efficiency of cathode current collectors. The electrical contact between the positive electrode materials ensures the electrical capacity of the energy storage device.

In one embodiment, the positive electrode material further includes a conductive agent and a binder, and the conductive agent and the binder are combined with the lithium cobaltate, the lithium manganate, the lithium nickel manganate, the The nickel-cobalt lithium manganate or lithium-rich manganese are mixed together.

In this embodiment, setting the positive electrode material requires mixing the conductive agent and the binder with lithium cobalt oxide, lithium manganate, lithium nickel manganate, lithium nickel cobalt manganate or lithium rich manganese to form a slurry, The slurry is coated on the surface of the positive electrode current collector to form a positive electrode sheet. The positive electrode material slurry is formed by adding lithium cobalt oxide, lithium manganate, lithium nickel manganate, lithium nickel cobalt manganate or lithium-rich manganese, a conductive agent and a binder into an N-methylpyrrolidone solvent and mixing evenly. In the slurry, the conductive agent can improve the conductivity of the positive electrode material. Adhesives can improve the firmness of the materials mixed together, for example, the paste can bond the materials together after curing. In addition, the adhesive can also form a firm bond between the positive electrode current collector and the positive electrode material.

Alternatively, the conductive agent may be conductive carbon black, carbon nanotubes, or the like. The binder may be polyvinylidene fluoride (PVDF).

Optionally, the positive electrode material is coated on the positive electrode current collector and cured to form a positive electrode sheet. For example, the negative electrode material is cured by drying, and the water evaporates after curing, so that the negative electrode material is solidified on the negative electrode current collector.

For example, the positive electrode material is solidified on the positive electrode current collector to form the substrate of the positive electrode sheet, and the substrate of the positive electrode sheet is cut to meet the requirements of different cells for the structure of the positive electrode sheet, and the corresponding structure of the positive electrode sheet is prepared.

The negative electrode material is coated on the negative electrode current collector and cured to form a negative electrode sheet. For example, the negative electrode material is solidified on the negative electrode current collector to form the substrate of the negative electrode sheet, and the substrate of the negative electrode sheet is cut to meet the requirements of different cells for the structure of the negative electrode sheet, and the negative electrode sheet of the corresponding structure is prepared.

In one embodiment, as shown in FIG. 1 , the energy storage device includes a plurality of the positive electrode sheets, a plurality of the negative electrode sheets and a plurality of gel polymer electrolyte membranes, the plurality of positive electrode sheets and the plurality of The negative electrode sheets are arranged alternately and stacked, and the gel polymer electrolyte membrane is arranged between the adjacent positive electrode sheets and the negative electrode sheets to form a stacked sheet structure.

The positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane may have a circular sheet structure, a square structure, a rectangular structure or an irregular patterned structure.

In this embodiment, the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane are prepared in the same structure, and the stack structure cell 2 is formed by alternately stacking the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane. The battery cell 2 is suitable for an energy storage device requiring a laminated structure battery cell.

For example, the housing 1 forms an accommodating cavity of the energy storage device, the battery cell 2 is arranged in the accommodating cavity, and ether-based electrolyte is added. After sealing the casing 1, an energy storage device is prepared. The prepared energy storage device is, for example, a coin cell battery.

For example, a positive electrode sheet, a negative electrode sheet, and a gel polymer electrolyte membrane are prepared in a disc structure. The diameters of the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane of the disc structure are, for example, 14 mm, 16 mm, 18 mm or 20 mm. The added ether-based electrolyte is, for example, 0.01 mL-0.03 mL.

In one embodiment, the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane are stacked and arranged to form a winding structure.

In this embodiment, the laminated structure of the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane is wound to form a battery core of the wound structure. In the battery core of the winding structure, the gel polymer electrolyte membrane forms a separation between the positive electrode sheet and the negative electrode sheet, and the gel polymer electrolyte membrane acts as a separator.

For example, the positive electrode sheet and the negative electrode sheet gel polymer electrolyte membrane are cut into sheet-like structures with a width of 3mm-5mm and a length of 350mm-500mm, and are stacked to form a rolled structure.

The battery core with the winding structure is put into the accommodating cavity of the casing, 0.1-0.5 mL of ether-based electrolyte is added, and the casing 1 is sealed. The prepared energy storage device is, for example, a coin cell battery.

Embodiment 1, as shown in FIG. 2 and FIG. 3 , according to the energy storage device in the above embodiment, the positive electrode material on the positive electrode sheet of the energy storage device includes lithium cobalt oxide. The negative electrode material on the negative electrode sheet includes polypyrrole-lithium vanadate. The electrolyte is ether-based electrolyte, and gel polymer electrolyte membranes are arranged on the positive electrode sheet and the negative electrode sheet.

At room temperature, the energy storage device was tested for discharge capacity at a voltage of 4.4V and a rate of 2C, 3C, 4C, and 5C, and cycled for 180 cycles.

In this embodiment, as shown in FIG. 2 , the discharge capacities of the energy storage device at rates of 2C, 3C, 4C, and 5C correspond to 172mAhg ^-1 , 167mAhg ^-1 , 165mAhg ^-1 , and 161mAhg ^-1 .

As shown in Figure 3, at 2C current density, the capacity remained stable after 180 cycles with little attenuation.

The energy storage device enables the energy storage device to have higher discharge capacity at different rates under the action of the gel polymer electrolyte, the ether-based electrolyte, the positive electrode material and the negative electrode material. Due to the protective layer formed by polypyrrole and the role of the gel polymer electrolyte, the dissolution of lithium vanadate and lithium titanate in the negative electrode material is effectively suppressed, the resistance of charge transfer is reduced, and the volume change of the electrode during cycling is buffered. The cycle performance of the energy storage device is further improved.

The discharge capacity of the energy storage device can maintain a high discharge capacity at different rates, and has better rate performance compared to the energy storage device in the prior art.

Comparative Example 1

Under the conditions of Example 1, the ether-based electrolyte was replaced with the lithium ion electrolyte used in the existing energy storage device. At room temperature, the discharge capacity of the energy storage device was tested at a voltage of 4.4V and a rate of 2C, 3C, 4C, and 5C. After 180 cycles, the discharge capacity was 170mAhg ^-1 , 160mAhg ^-1 , 152mAhg ^-1 , 140mAhg ^-1 , the capacity retention rate of 180 cycles is 85%.

By comparison, it can be seen that the ether-based electrolyte in the present disclosure can effectively improve the retention rate of the discharge capacity. The discharge capacity can be kept stable under the condition of multiple cycles. The ether-based electrolyte has an obvious effect on the gel polymer electrolyte, improving the wettability and increasing the electrical conductivity, thereby improving the performance at different rates.

In the second embodiment, the positive electrode material on the positive electrode sheet of the energy storage device includes lithium manganate. The negative electrode material on the negative electrode sheet includes polypyrrole-lithium vanadate. The electrolyte is ether-based electrolyte, and gel polymer electrolyte membranes are arranged on the positive electrode sheet and the negative electrode sheet.

At room temperature, the energy storage device was tested for discharge capacity at a voltage of 4.2V and a rate of 2C, 3C, 4C, and 5C, and cycled for 180 cycles.

In this embodiment, corresponding to the rates of 2C, 3C, 4C, and 5C, the discharge capacity of the energy storage device corresponds to 125mAhg ^-1 , 123mAhg ^-1 , 122mAhg ^-1 , and 120mAhg ^-1 .

In the third embodiment, the positive electrode material on the positive electrode sheet of the energy storage device includes a high nickel ternary. The negative electrode material on the negative electrode sheet includes polypyrrole-lithium vanadate. The electrolyte is ether-based electrolyte, and gel polymer electrolyte membranes are arranged on the positive electrode sheet and the negative electrode sheet.

At room temperature, the energy storage device was tested for the discharge capacity at a voltage of 4.3V and a rate of 2C, 3C, 4C, and 5C for 180 cycles.

In this embodiment, corresponding to the rates of 2C, 3C, 4C, and 5C, the discharge capacity of the energy storage device corresponds to 180mAhg ^-1 , 177mAhg ^-1 , 175mAhg ^-1 , and 174mAhg ^-1 .

In the above embodiments, through the action of the gel polymer electrolyte membrane, the energy storage device can maintain the discharge capacity without loss under various angles of bending, extrusion and folding, and has excellent flexibility. In the case of perforation, the stability of the energy storage device will not be destroyed, so that the energy storage device has excellent safety performance.

The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Repeat.

While some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art will appreciate that the above examples are provided for illustration only, and are not intended to limit the scope of the present disclosure. Those skilled in the art will appreciate that modifications may be made to the above embodiments without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

An energy storage device, comprising a positive electrode sheet, a negative electrode sheet, a gel polymer electrolyte membrane and an ether-based electrolyte;

The gel polymer electrolyte membrane is arranged between the positive electrode sheet and the negative electrode sheet, and the ether-based electrolyte is filled between the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane ;

The components of the ether-based electrolyte include: lithium bisfluorosulfonimide, 1,2-dimethoxyethane and 1,1,2,2-tetrafluoroethyl 2,2,3,3- Tetrafluoropropane ether.
The energy storage device according to claim 1, wherein the lithium bisfluorosulfonimide, the 1,2-dimethoxyethane and the 1,1,2,2-tetrafluoro The molar ratio of ethyl 2,2,3,3-tetrafluoropropane ether is 0.5-1.5:0.5-1.5:3.
The energy storage device according to any one of claims 1-2, wherein the gel polymer electrolyte membrane comprises polyvinyl alcohol-lithium sulfate and/or polyvinyl alcohol-lithium nitrate.
The energy storage device according to any one of claims 1-3, wherein the thickness of the gel polymer electrolyte membrane is 10 μm-50 μm.
The energy storage device according to any one of claims 1-4, wherein the negative electrode sheet comprises a negative electrode current collector and a negative electrode material coated on the negative electrode current collector, and the negative electrode material comprises polypyrrole - Lithium vanadate and/or polypyrrole-lithium titanate.
The energy storage device according to claim 5, wherein the negative electrode material further comprises a conductive agent and a binder, and the conductive agent and the binder are combined with the polypyrrole-lithium vanadate and/or The polypyrrole-lithium titanate is mixed together.
The energy storage device according to any one of claims 1-6, wherein the positive electrode sheet comprises a positive electrode current collector and a positive electrode material coated on the positive electrode current collector, and the positive electrode material comprises cobalt acid Lithium, lithium manganate, lithium nickel manganate, lithium nickel cobalt manganate or lithium rich manganese.
The energy storage device according to claim 7, wherein the positive electrode material further comprises a conductive agent and a binder, and the conductive agent and the binder are combined with the lithium cobaltate and the lithium manganate. , the lithium nickel manganese oxide, the lithium nickel cobalt manganate or the lithium rich manganese are mixed together.
The energy storage device according to any one of claims 1-8, characterized in that, comprising a plurality of the positive electrode sheets, a plurality of the negative electrode sheets and a plurality of gel polymer electrolyte membranes, the plurality of positive electrode sheets The sheets and the plurality of negative electrode sheets are alternately and stacked, and the gel polymer electrolyte membrane is arranged between the adjacent positive electrode sheets and the negative electrode sheets to form a stacked sheet structure.
The energy storage device according to any one of claims 1 to 9, wherein the positive electrode sheet, the negative electrode sheet and the gel polymer electrolyte membrane are stacked and formed in a winding structure.