Composite solid electrolyte, preparation method thereof and all-solid-state lithium ion battery

Abstract

The invention provides a composite solid electrolyte, a preparation method thereof and an all-solid-state lithium ion battery. The composite solid electrolyte comprises an oxide electrolyte, and a sintering aid, a plasticizer, a polymer and a lithium salt which are filled in the oxide electrolyte, wherein the mass ratio of the oxide electrolyte to the sintering aid to the polymer to the lithium salt to the plasticizer is (50-95):(1-10):(0.1-40):(0.1-40):(0.1-40). The composite solid electrolyte provided by the invention can effectively reduce the interface impedance between electrolyte grains, and improve the cycle efficiency, the cycle stability and other qualities of the lithium ion battery.

Description

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a composite solid electrolyte, a preparation method thereof, and an all-solid lithium ion battery. Background technique

[0002] In recent years, among various commercial rechargeable and dischargeable chemical energy storage devices, lithium-ion batteries have attracted much attention since they were put into the market due to their high energy density and long service life. and other fields have been widely used. However, the organic electrolyte used in lithium-ion batteries is volatile, flammable, and explosive, which can easily cause safety accidents. As the key material of all-solid-state lithium-ion batteries, solid electrolytes have high mechanical strength and excellent density. And the ability to inhibit the growth of lithium dendrites can effectively improve the safety and stability of the battery. Therefore, the use of solid electrolytes instead of organic electro...

Examples

preparation example Construction

[0040] Another aspect of the present invention provides a method for preparing a composite solid electrolyte, comprising:

[0041] The mixed powder containing oxide electrolyte, sintering aid and pore-forming agent is sequentially subjected to tableting and sintering treatment to obtain a composite solid electrolyte precursor;

[0042] After infiltrating the composite solid electrolyte precursor with a slurry containing polymer monomers, lithium salts, initiators and plasticizers, and then undergoing thermal initiation treatment, the composite solid electrolyte is obtained.

[0043] The above-mentioned oxide electrolytes, sintering aids, polymerized monomers, initiators, lithium salts and plasticizers are used as raw materials for composite solid electrolytes. Reasonable adjustment of the ratio / dosage of each raw material can further improve the ionic conductivity of composite solid electrolytes, etc. Performance, in specific implementation, in the above raw materials, the mas...

Embodiment 1

[0062] The composite solid electrolyte and lithium-ion battery provided by this embodiment are as follows: Figure 4 As shown, the lithium ion battery includes a positive electrode sheet 1, a negative electrode sheet 2 and a composite solid electrolyte 3, wherein the composite solid electrolyte 3 includes a core layer and a first surface positioned at the core layer and a second surface opposite to the first surface Polymer electrolyte layer 6 (polymer electrolyte 6 is composed of plasticizer, polymer and lithium salt), the core layer includes oxide electrolyte 4 and sintering aid 5 filled in oxide electrolyte 4 and filled in oxide electrolyte Plasticizer, polymer and lithium salt in 4 (plasticizer, polymer and lithium salt form polymer electrolyte 6); Wherein, positive electrode sheet 1 comprises current collector and the positive electrode function layer that is coated on collector, this The surface density of the positive electrode functional layer is 10mg / cm 2 , its raw m...

Embodiment 2

[0078] The composite solid electrolyte and lithium-ion battery provided by this embodiment are as follows: Figure 4 As shown, the lithium ion battery includes a positive electrode sheet 1, a negative electrode sheet 2 and a composite solid electrolyte 3, wherein the composite solid electrolyte 3 includes a core layer and a first surface positioned at the core layer and a second surface opposite to the first surface Polymer electrolyte layer 6 (polymer electrolyte 6 is composed of plasticizer, polymer and lithium salt), the core layer includes oxide electrolyte 4 and sintering aid 5 filled in oxide electrolyte 4 and filled in oxide electrolyte Plasticizer, polymer and lithium salt in 4 (plasticizer, polymer and lithium salt form polymer electrolyte 6); Wherein, positive electrode sheet 1 comprises current collector and the positive electrode function layer that is coated on collector, this The surface density of the positive electrode functional layer is 12mg / cm 2 , whose raw...

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a composite solid electrolyte, a preparation method thereof, and an all-solid lithium ion battery. Background technique

[0002] In recent years, among various commercial rechargeable and dischargeable chemical energy storage devices, lithium-ion batteries have attracted much attention since they were put into the market due to their high energy density and long service life. and other fields have been widely used. However, the organic electrolyte used in lithium-ion batteries is volatile, flammable, and explosive, which can easily cause safety accidents. As the key material of all-solid-state lithium-ion batteries, solid electrolytes have high mechanical strength and excellent density. And the ability to inhibit the growth of lithium dendrites can effectively improve the safety and stability of the battery. Therefore, the use of solid electrolytes instead of organic electro...

Examples

preparation example Construction

[0040] Another aspect of the present invention provides a method for preparing a composite solid electrolyte, comprising:

[0041] The mixed powder containing oxide electrolyte, sintering aid and pore-forming agent is sequentially subjected to tableting and sintering treatment to obtain a composite solid electrolyte precursor;

[0042] After infiltrating the composite solid electrolyte precursor with a slurry containing polymer monomers, lithium salts, initiators and plasticizers, and then undergoing thermal initiation treatment, the composite solid electrolyte is obtained.

[0043] The above-mentioned oxide electrolytes, sintering aids, polymerized monomers, initiators, lithium salts and plasticizers are used as raw materials for composite solid electrolytes. Reasonable adjustment of the ratio / dosage of each raw material can further improve the ionic conductivity of composite solid electrolytes, etc. Performance, in specific implementation, in the above raw materials, the mas...

Embodiment 1

[0062] The composite solid electrolyte and lithium-ion battery provided by this embodiment are as follows: Figure 4 As shown, the lithium ion battery includes a positive electrode sheet 1, a negative electrode sheet 2 and a composite solid electrolyte 3, wherein the composite solid electrolyte 3 includes a core layer and a first surface positioned at the core layer and a second surface opposite to the first surface Polymer electrolyte layer 6 (polymer electrolyte 6 is composed of plasticizer, polymer and lithium salt), the core layer includes oxide electrolyte 4 and sintering aid 5 filled in oxide electrolyte 4 and filled in oxide electrolyte Plasticizer, polymer and lithium salt in 4 (plasticizer, polymer and lithium salt form polymer electrolyte 6); Wherein, positive electrode sheet 1 comprises current collector and the positive electrode function layer that is coated on collector, this The surface density of the positive electrode functional layer is 10mg / cm 2 , its raw m...

Embodiment 2

[0078] The composite solid electrolyte and lithium-ion battery provided by this embodiment are as follows: Figure 4 As shown, the lithium ion battery includes a positive electrode sheet 1, a negative electrode sheet 2 and a composite solid electrolyte 3, wherein the composite solid electrolyte 3 includes a core layer and a first surface positioned at the core layer and a second surface opposite to the first surface Polymer electrolyte layer 6 (polymer electrolyte 6 is composed of plasticizer, polymer and lithium salt), the core layer includes oxide electrolyte 4 and sintering aid 5 filled in oxide electrolyte 4 and filled in oxide electrolyte Plasticizer, polymer and lithium salt in 4 (plasticizer, polymer and lithium salt form polymer electrolyte 6); Wherein, positive electrode sheet 1 comprises current collector and the positive electrode function layer that is coated on collector, this The surface density of the positive electrode functional layer is 12mg / cm 2 , whose raw...

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