Flexible lithium ion battery black phosphorus nanosheet-graphene composite film anode, and preparation thereof

Abstract

The invention belongs to the field of electrochemistry battery, and more specifically relates to a black phosphorus nanosheet-graphene composite film anode used for flexible lithium ion batteries, and a preparation method thereof. According to the preparation method, high purity and large scale black phosphorus blocks are synthesized via mineral substance assistant vapor transporting method with high efficiency; a large amount of clean and high quality black phosphorus sheets are prepared in water via ultrasound treatment; the clean and high quality black phosphorus sheets and high conductive graphene nanosheets prepared via intercalation stripping method are subjected to mixing ultrasonic dispersion; and flexible high-strength laminated composite film is prepared via vacuum filtration. The preparation process of the flexible high-strength laminated composite film is simple and controllable; large scale low cost preparation can be realized; black phosphorus nanosheets are high in capacity, graphene is high in electrical conductivity, and the black phosphorus nanosheets and graphene both possess two-dimensional structures high in flexibility and strength, so that problems the black phosphorus is poor in electrical conductivity and stability are solved, lithium ion battery capacity, cycling stability, and entire energy density are increased, and lithium ion battery electrode integrated flexible design is realized.

Description

Technical field

[0001] The invention belongs to the field of electrochemical batteries, and specifically relates to a black phosphorous nanosheet-graphene composite film negative electrode for a flexible lithium ion battery and a preparation method thereof. Background technique

[0002] With the increasing demand for various new technologies and new technologies, especially wearable devices, the high-efficiency energy storage devices that are the basis for these applications of power sources have received widespread attention, and they also have high energy density, power density and good circulation for development. The flexible characteristics of stable secondary batteries place high demands. Electrode materials and their structural design are key factors in the development of high-performance flexible secondary batteries. Current commercial secondary lithium ion batteries mainly use graphite, carbon fiber, lithium titanate and their composite materials as negative electrodes,...

Examples

preparation example Construction

[0041] In the specific implementation process, the present invention proposes a black phosphorus nanosheet-graphene composite film negative electrode for lithium ion batteries and a preparation method thereof. The black phosphorus block is combined with a mineral-assisted gas phase transport method, and then prepared by Tip ultrasound. Black phosphorous nano flake powder, black phosphorous nano flakes and graphene are dispersed in an organic solvent in a certain proportion, and then ultrasonicated and vacuum filtered on the organic membrane. After vacuum drying, the film is directly peeled off from the organic membrane to obtain black phosphorus Nanosheet-graphene composite film negative electrode. Specific steps are as follows:

[0042] (1) Using mineral-assisted gas-phase transport method to synthesize black phosphorus bulk: red phosphorus, gold tin alloy (AuSn, alloy grades such as: AuSn20, AuSn27 or AuSn90, etc.) and tin tetraiodide according to 900:360:18 The weight ratio i...

Embodiment 1

[0052] 1000mg of black phosphorus block is put into a mortar and ground into powder (see figure 2 ), put the black phosphorus powder into a glass bottle containing 200 mL of deionized water (the black phosphorus content is 5 mg / mL). Use Tip ultrasonic to peel off the black phosphorous block to prepare black phosphorous nanosheets (ultrasonic power is 380W, ultrasonic time is 3h), after the end of the ultrasonic, let stand for 12h, centrifuge at 5000 rpm for 30min, take out the supernatant, and obtain black phosphorous nano Dispersion of tablets in water. The above dispersion was vacuum filtered and washed with ethanol, and then dried under vacuum at 60°C for 12 hours to obtain black phosphorous nanosheet powder (average thickness of about 5.2nm, see image 3 g; the lateral dimension is 50~250nm, see Figure 4 a-c). 12mg (80wt%) of black phosphorus nanoplate powder and 3mg (20wt%) of graphene were added to N-methylpyrrolidone (40mL) organic solvent, and ordinary ultrasound (190...

Technical field

[0001] The invention belongs to the field of electrochemical batteries, and specifically relates to a black phosphorous nanosheet-graphene composite film negative electrode for a flexible lithium ion battery and a preparation method thereof. Background technique

[0002] With the increasing demand for various new technologies and new technologies, especially wearable devices, the high-efficiency energy storage devices that are the basis for these applications of power sources have received widespread attention, and they also have high energy density, power density and good circulation for development. The flexible characteristics of stable secondary batteries place high demands. Electrode materials and their structural design are key factors in the development of high-performance flexible secondary batteries. Current commercial secondary lithium ion batteries mainly use graphite, carbon fiber, lithium titanate and their composite materials as negative electrodes,...

Examples

preparation example Construction

[0041] In the specific implementation process, the present invention proposes a black phosphorus nanosheet-graphene composite film negative electrode for lithium ion batteries and a preparation method thereof. The black phosphorus block is combined with a mineral-assisted gas phase transport method, and then prepared by Tip ultrasound. Black phosphorous nano flake powder, black phosphorous nano flakes and graphene are dispersed in an organic solvent in a certain proportion, and then ultrasonicated and vacuum filtered on the organic membrane. After vacuum drying, the film is directly peeled off from the organic membrane to obtain black phosphorus Nanosheet-graphene composite film negative electrode. Specific steps are as follows:

[0042] (1) Using mineral-assisted gas-phase transport method to synthesize black phosphorus bulk: red phosphorus, gold tin alloy (AuSn, alloy grades such as: AuSn20, AuSn27 or AuSn90, etc.) and tin tetraiodide according to 900:360:18 The weight ratio i...

Embodiment 1

[0052] 1000mg of black phosphorus block is put into a mortar and ground into powder (see figure 2 ), put the black phosphorus powder into a glass bottle containing 200 mL of deionized water (the black phosphorus content is 5 mg / mL). Use Tip ultrasonic to peel off the black phosphorous block to prepare black phosphorous nanosheets (ultrasonic power is 380W, ultrasonic time is 3h), after the end of the ultrasonic, let stand for 12h, centrifuge at 5000 rpm for 30min, take out the supernatant, and obtain black phosphorous nano Dispersion of tablets in water. The above dispersion was vacuum filtered and washed with ethanol, and then dried under vacuum at 60°C for 12 hours to obtain black phosphorous nanosheet powder (average thickness of about 5.2nm, see image 3 g; the lateral dimension is 50~250nm, see Figure 4 a-c). 12mg (80wt%) of black phosphorus nanoplate powder and 3mg (20wt%) of graphene were added to N-methylpyrrolidone (40mL) organic solvent, and ordinary ultrasound (190...

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