CN112086626A - Conductive composite electrode positive electrode material of all-solid-state battery - Google Patents

Abstract

The invention discloses a conductive composite electrode positive electrode material of an all-solid-state battery, comprising a positive electrode substrate, and a solid ion conductor is compounded on at least one side of the positive electrode substrate. In the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention, the solid-state ionic conductor and the positive-electrode base material are compounded into one, so that the bonding force and wettability between the solid-state ionic conductor and the positive-electrode base material can be effectively ensured, and the Reduce the interface resistance between solid ionic conductors and electrodes. When in use, a solid-state ion conductor is also compounded on the negative electrode substrate, and an all-solid-state battery can be obtained by compounding or merging the solid-state ion conductors of the positive electrode substrate and the negative electrode substrate, which can effectively simplify the production process and effectively Enhance the bonding degree and wettability between the solid ionic conductor and the electrode, and reduce the interface resistance between the solid ionic conductor and the electrode.

Description

Conductive Composite Electrode Cathode Materials for All-Solid-State Batteries

technical field

The invention belongs to the technical field of energy storage devices, in particular to a conductive composite electrode positive electrode material of an all-solid-state battery.

Background technique

Solid-state batteries are a type of battery technology. Unlike lithium-ion batteries and lithium-ion polymer batteries that are commonly used today, solid-state batteries are batteries that use solid electrodes and solid electrolytes. The traditional liquid lithium battery is also vividly called "rocking chair battery" by scientists. The two ends of the rocking chair are the positive and negative poles of the battery, and the middle is the electrolyte (liquid). And lithium ions are like excellent athletes, running back and forth between the two ends of the rocking chair. During the movement of lithium ions from the positive electrode to the negative electrode to the positive electrode, the charging and discharging process of the battery is completed. The principle of solid-state batteries is the same, except that the electrolyte is solid, with a density and structure that allows more charged ions to gather at one end, conduct larger currents, and increase battery capacity. Therefore, for the same amount of power, the solid-state battery will become smaller. Not only that, since there is no electrolyte in the solid-state battery, the storage will become easier. When used in large equipment such as automobiles, there is no need to add additional cooling pipes, electronic controls, etc., which not only saves costs, but also effectively reduces the cost. weight.

Although the existing solid-state batteries can meet the use requirements to a certain extent, they still have the following shortcomings:

1) Insufficient binding force between solid ionic conductors and electrodes;

2) The affinity between the solid-state ionic conductor and the electrode is poor;

3) The interface resistance between the solid ionic conductor and the electrode is relatively large.

SUMMARY OF THE INVENTION

In view of this, the purpose of the present invention is to provide a conductive composite electrode positive electrode material for an all-solid-state battery, which can effectively enhance the bonding force and wettability between the solid-state ion conductor and the electrode, and can effectively reduce the solid-state ion conductor and the electrode. The interfacial resistance between the electrodes increases the ion permeability.

To achieve the above object, the present invention provides the following technical solutions:

A conductive composite electrode positive electrode material for an all-solid-state battery,

It includes a positive electrode substrate, and a solid ion conductor is compounded on at least one side of the positive electrode substrate.

Further, a groove is provided on the side surface of the positive electrode substrate on which the solid ionic conductor is provided, and the side of the solid ionic conductor facing the positive electrode substrate is embedded in the groove.

Further, the width of the groove gradually increases along the direction from the groove bottom to the notch.

Further, embedded holes are arrayed on the side of the positive electrode on which the solid ionic conductor is provided, and the side of the solid ionic conductor facing the positive electrode is embedded in the embedded hole.

Further, among the two radial cross-sections obtained from any two radial cross-sections perpendicular to the axis of the recessed hole in the same recessed hole, the geometric dimension of the radial cross-section near the bottom of the recessed hole Less than or equal to the geometric dimension of the radial section close to the side of the insert hole orifice.

Further, the positive electrode substrate adopts but is not limited to lithium iron phosphate, ternary material, sulfur-containing conductive material, porous carbon layer air battery electrode containing metal or organic material, layered metal oxide material or oxygen-containing organic polymer material. production.

Further, the solid ionic conductor is made of one or a mixture of at least two of gels, oxides, sulfides and organic polymers.

Further, the positive electrode substrate is made of a mixture of positive electrode active material and solid ionic conductor material.

Further, the molar ratio between the solid ion conductor material and the positive electrode active material is less than or equal to 100%

Further, the positive electrode active material is uniformly distributed in the form of particles, and the solid ion conductor material is filled in the gaps of the positive electrode active material particles.

The beneficial effects of the present invention are:

In the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention, the solid-state ionic conductor and the positive-electrode base material are compounded into one, so that the bonding force and wettability between the solid-state ionic conductor and the positive-electrode base material can be effectively ensured, and the Reduce the interface resistance between solid ionic conductors and electrodes. When in use, a solid-state ion conductor is also compounded on the negative electrode substrate, and the solid-state ion conductor of the positive electrode substrate and the negative electrode substrate is compounded or fused together to obtain an all-solid-state battery, which can effectively simplify the production process and effectively Enhance the bonding degree and wettability between the solid-state ion conductor and the electrode, reduce the interface resistance between the solid-state ion conductor and the electrode, and improve the ion permeability.

By making the positive electrode with a mixture of positive electrode active material and solid ionic conductor material, the solid ionic conductor material mixed in the positive electrode and the solid ionic conductor compounded on the side of the positive electrode can be ionically connected, which can effectively improve the ion permeability. And reduce the interface resistance between the solid state and the electrode.

Description of drawings

In order to make the purpose, technical solutions and beneficial effects of the present invention clearer, the present invention provides the following drawings for description:

1 is a schematic structural diagram of Example 1 of the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention;

Fig. 2 is a detailed view of A of Fig. 1;

3 is a schematic view of the microstructure of the positive electrode material of the present embodiment;

4 is a position reference diagram before the positive electrode material and the negative electrode material are combined;

5 is a schematic structural diagram of an all-solid-state battery obtained by using the conductive composite electrode positive electrode material of the all-solid-state battery of the present embodiment;

6 is a schematic structural diagram of Embodiment 2 of the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention;

Fig. 7 is A detailed view of Fig. 5;

8 is a schematic structural diagram of an all-solid-state battery cell composed of the positive electrode material and the negative electrode material of the present embodiment; specifically, the structural schematic diagram when the positive electrode material and the negative electrode material are separated;

FIG. 9 is a schematic structural diagram of the positive electrode material and the negative electrode material in FIG. 7 after being combined together;

10 is a schematic structural diagram when the difference between the number of positive electrode substrates and the number of negative electrode substrates is equal to 1 in the all-solid-state battery cell composed of the positive electrode material of the present embodiment;

FIG. 11 is a schematic structural diagram of an all-solid-state battery cell composed of the positive electrode material of this embodiment when the number of positive electrode substrates is equal to the number of negative electrode substrates.

Detailed ways

The present invention is further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

Example 1

As shown in FIG. 1 , it is a schematic structural diagram of Example 1 of the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention. The conductive composite electrode positive electrode material of the all-solid-state battery in this embodiment includes a positive electrode substrate 10 , and a solid ion conductor 11 is compounded on at least one side of the positive electrode substrate 10 . In this embodiment, the solid ion conductor 11 is only provided on one side of the positive electrode substrate 10 .

Further, a groove 12 is provided on the side of the positive electrode substrate 10 provided with the solid ionic conductor 11, and the side of the solid ionic conductor 11 facing the positive electrode substrate 10 is embedded in the groove 12, which can further strengthen the positive electrode substrate 10 and the solid ionic conductor. Bond strength and wettability between conductors 11 . Specifically, the grooves 12 in this embodiment can be set in various structures, such as wave grooves, triangular sawtooth grooves, trapezoidal grooves, V-shaped grooves, and rectangular grooves. In order to increase the bonding area between the solid-state ion conductor 11 and the side surface of the positive electrode 10 , the width of the groove 12 in this embodiment gradually increases along the direction from the groove bottom to the groove opening. The grooves 12 in this embodiment are configured as wave grooves. By arranging the grooves 12 in the positive electrode 10 , the bonding strength and wettability between the positive electrode 10 and the solid ionic conductor 11 can be effectively enhanced, and the interface resistance between the positive electrode 10 and the solid ionic conductor 11 can be reduced.

In addition, embedded holes may also be arranged in an array on the side of the positive electrode 10 where the solid ion conductors 11 are provided, and the side of the solid ion conductors 11 facing the positive electrode 10 is embedded in the embedded holes. Specifically, among any two radial sections perpendicular to the axis of the embedded hole, the geometrical dimension of the radial section close to the bottom of the embedded hole is smaller than or equal to that close to the embedded hole. The geometry of the radial section on one side of the orifice. The embedded hole can adopt various structures, such as the use of a conical embedded hole, a square conical embedded hole, and a flared embedded hole, etc., which will not be described again.

Specifically, in some embodiments, the grooves 12 or embedded holes may be provided only on the side of the positive electrode 10 where the solid-state ionic conductor 11 is provided, or the grooves 12 may be provided on the side of the positive electrode 10 where the solid-state ionic conductor 11 is provided at the same time. and insert holes.

Further, the positive electrode substrate 10 of this embodiment adopts but is not limited to lithium iron phosphate, ternary materials, sulfur-containing conductive materials, porous carbon layer air battery electrodes containing metal or organic materials, layered metal oxide materials or oxygen-containing organic materials. Made of polymer material. The solid ion conductor 11 of this embodiment is made of one or a mixture of at least two of gels, oxides, sulfides and organic polymers.

Further, the positive electrode substrate 10 is made of a mixture of the positive electrode active material 14 and the solid ion conductor material 15 . And in the positive electrode substrate, the molar ratio between the solid ion conductor material and the positive electrode active material is less than or equal to 100%. In terms of microstructure, the positive electrode active material is uniformly distributed in the form of particles, and the gaps of the positive electrode active material particles are filled with solid ion conductor material, as shown in FIG. 3 . By making the positive electrode with a mixture of positive electrode active material and solid ionic conductor material, the solid ionic conductor material mixed in the positive electrode and the solid ionic conductor compounded on the side of the positive electrode can be ionically connected, which can effectively improve the ion permeability. And reduce the interface resistance between the solid state and the electrode.

The solid ion conductor material 15 and the solid ion conductor 11 in this embodiment are made of the same material. Of course, the solid ion conductor material 15 and the solid ion conductor 11 can also be made of different materials, as long as the solid ion conductor 11 and the positive electrode substrate can be strengthened. The wettability between the solid ion conductors 10 and the interface resistance between the solid ion conductor 11 and the positive electrode substrate 10 can be reduced, and the ion permeability can be increased.

As shown in FIG. 4 , it is a schematic structural diagram of an all-solid-state battery cell obtained by using the conductive composite electrode positive electrode material of the all-solid-state battery and the conductive composite electrode negative electrode material of the all-solid-state battery in this embodiment. Specifically, the conductive composite electrode negative electrode material of the all-solid-state battery includes a negative electrode substrate 20, and a solid ionic conductor 21 is compounded on the negative electrode substrate 20, and the solid ionic conductor 11 arranged on the positive electrode substrate 10 and the The solid-state ion conductors 21 on the material 20 are combined or fused together to obtain an all-solid-state battery, as shown in FIG. 5 .

In the conductive composite electrode positive electrode material of the all-solid-state battery of this embodiment, the solid ionic conductor and the positive electrode substrate are combined into one, so that the bonding force and wettability between the solid ionic conductor and the positive electrode substrate can be effectively ensured. And reduce the interface resistance between the solid ionic conductor and the electrode. When in use, a solid-state ion conductor is also compounded on the negative electrode substrate, and the solid-state ion conductor of the positive electrode substrate and the negative electrode substrate is compounded or fused together to obtain an all-solid-state battery, which can effectively simplify the production process and effectively Enhance the bonding degree and wettability between the solid ionic conductor and the electrode, and reduce the interface resistance between the solid ionic conductor and the electrode.

Example 2

As shown in FIG. 6 , it is a schematic structural diagram of Example 1 of the conductive composite electrode positive electrode material of the all-solid-state battery of the present invention. The conductive composite electrode positive electrode material of the all-solid-state battery in this embodiment includes a positive electrode substrate 10 , and a solid ion conductor 11 is compounded on at least one side of the positive electrode substrate 10 . In this embodiment, solid ion conductors 11 are respectively provided on both sides of the positive electrode substrate 10 .

Other structures of this embodiment are the same as those of Embodiment 1, and will not be described again.

As shown in FIG. 8 , it is a schematic structural diagram of an all-solid-state battery cell obtained by using the conductive composite electrode positive electrode material of the all-solid-state battery and the conductive composite electrode negative electrode material of the all-solid-state battery in this embodiment. Specifically, the conductive composite electrode negative electrode material of the all-solid-state battery includes a negative electrode substrate 20, and a solid-state ion conductor 21 is compounded on the negative electrode substrate 20. The negative electrode materials of the composite electrode are staggered and compounded together, that is, the solid-state ionic conductor 11 arranged on the positive electrode substrate 10 and the solid-state ionic conductor 21 arranged on the adjacent negative electrode substrate 20 are compounded or fused together, so as to obtain a complete composite electrode. Solid state battery.

The conductive composite electrode positive electrode material of the all-solid-state battery of this embodiment can be used to form all-solid-state battery cells with various structures:

As shown in FIG. 9 , it is a schematic structural diagram when the number N of the positive electrode substrates 10 and the number M of the negative electrode substrates 20 satisfy the relationship M-N=1. Specifically, the number of the positive electrode substrates 10 in the illustration is 1, The number of negative electrode substrates was 2.

As shown in FIG. 10 , it is a schematic structural diagram when the number N of the positive electrode substrates 10 and the number M of the negative electrode substrates 20 satisfy the relationship N−M=1. Specifically, the number of the positive electrode substrates 10 in the illustration is 3, The number of negative electrode substrates is 2, and the two positive electrode substrates 10 located at both ends adopt the structure in Example 1.

As shown in FIG. 11 , it is a schematic structural diagram when the number N of the positive electrode substrates 10 and the number M of the negative electrode substrates 20 satisfy the relationship N=M. Specifically, the number of the positive electrode substrates 10 in the illustration is 3, The number of negative electrode substrates is 3, and one positive electrode substrate 10 at one end adopts the structure in Example 1.

Other structures of this embodiment are the same as those of Embodiment 1, and will not be described again.

The above-mentioned embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. The protection scope of the present invention is subject to the claims.

Claims (10)

1. a conductive type composite electrode positive material of an all-solid-state battery, characterized in that: A positive electrode substrate (10) is included, and a solid ion conductor (11) is compounded on at least one side surface of the positive electrode substrate (10). 2. The conductive type composite electrode positive electrode material of all-solid-state battery according to claim 1, is characterized in that: A groove (12) is provided on the side of the positive electrode substrate (10) provided with the solid ionic conductor (11), and the solid ionic conductor (11) is embedded in the side facing the positive electrode substrate (10). into the groove (12). 3. The conductive type composite electrode positive electrode material of all-solid-state battery according to claim 2, is characterized in that: The width of the groove (12) increases gradually along the direction from the groove bottom to the groove. 4. The conductive type composite electrode positive electrode material of all-solid-state battery according to claim 1, is characterized in that: The side surface of the positive electrode (10) provided with the solid ionic conductor (11) is provided with embedded holes in an array, and the side of the solid ionic conductor (11) facing the positive electrode (10) is embedded in the embedded hole . 5. The conductive composite electrode positive electrode material of all-solid-state battery according to claim 4, characterized in that: Of any two radial sections perpendicular to the axis of the embedded hole, the geometric dimension of the radial section close to the bottom of the embedded hole is less than or equal to two radial sections cut from the same embedded hole. The geometrical dimension of the radial cross-section on the side close to the orifice of the insert. 6. The conductive type composite electrode positive electrode material of all-solid-state battery according to claim 1, is characterized in that: The positive electrode substrate (10) adopts but is not limited to lithium iron phosphate, ternary material, sulfur-containing conductive material, porous carbon layer air battery electrode containing metal or organic material, layered metal oxide material or oxygen-containing organic polymer. material. 7. The conductive composite electrode positive electrode material of all-solid-state battery according to claim 1, characterized in that: The solid ionic conductor (11) is made of one or a mixture of at least two of gels, oxides, sulfides and organic polymers. 8. The conductive composite electrode positive electrode material of the all-solid-state battery according to any one of claims 1-7, characterized in that: The positive electrode substrate (10) is made of a mixture of a positive electrode active material and a solid ion conductor material. 9. The conductive composite electrode positive electrode material of all-solid-state battery according to claim 8, characterized in that: The molar ratio between the solid ion conductor material and the positive electrode active material is less than or equal to 100%. 10. The conductive composite electrode positive electrode material of all-solid-state battery according to claim 8, characterized in that: The positive electrode active material is uniformly distributed in the form of particles, and the solid ion conductor material is filled in the gaps of the positive electrode active material particles.

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