CN115312876A - Quick-charging type high-capacity button battery and preparation method thereof - Google Patents

Abstract

The invention discloses a fast-charging high-capacity button battery and a preparation method thereof, comprising a winding core, the winding core comprising a diaphragm, the diaphragm is wound to form a spiral structure, a positive electrode sheet and a negative electrode sheet are fixedly attached between the spiral gaps of the diaphragm, and the end of the diaphragm The positive electrode and negative electrode are fixedly connected to the tabs, the bottom and top of the outer wall of the winding core are respectively sleeved with a support ring and a sealing rubber ring, the outer wall of the support ring is fixedly sleeved with the positive electrode shell, and the top of the sealing rubber ring is fixedly connected to the flange cover. The flip cover is fixedly connected to the positive electrode shell, and the two tabs are electrically connected to the positive electrode shell and the inner wall of the flip cover, respectively, and the positive and negative electrode sheets are prepared according to the ratio. The supporting ring, soaking liquid, sealing and other processes form the core, and coat the supporting ring structure to prepare an uncharged bare button battery, and the battery is prepared through the process of forming, aging, and standing to prepare the button battery. The battery has the excellent performance of good consistency, low internal resistance, high capacity, and fast charging support.

Description

A fast-charging high-capacity button battery and preparation method thereof

technical field

The invention relates to the technical field of button batteries, in particular to a fast-charging high-capacity button battery and a preparation method thereof.

Background technique

The energy crisis is one of the hottest topics in today's society, and it is related to the survival and development of the world. The continuous shortage of global energy in recent decades has prompted people to vigorously study alternative new energy sources, and chemical power sources, as energy storage and conversion devices, have become an important means of efficient energy use. Therefore, lithium-ion batteries stand out for their advantages of good safety, high voltage, small self-discharge, no memory and stable cycle performance, and become a hot spot for commercial development in the international battery industry. With the continuous development and maturity of 5G small smart devices, lithium-ion batteries, one of its high-energy power sources, will undoubtedly have a broader demand. The capacity and rate performance of lithium-ion button batteries are the main direction and direction of lithium-ion battery research. Hot spot, at present, the main structure and method of preparing button batteries at home and abroad are three-piece steel shell winding type, soft-pack laminated type, soft-pack winding type, etc. Compared with this preparation method, the operation is simple, the preparation conditions are easy to control, and it is easy to Industrialized production is carried out, but the consistency of preparation, capacity performance, and rate performance are not superior enough, and in the preparation methods known so far, it is difficult to obtain a button battery with good consistency, low internal resistance, high capacity, and support 3C fast charging. Preparation method, for this reason we propose a fast-charging high-capacity button battery and its preparation method for solving the above problems.

Contents of the invention

The object of the present invention is to provide a fast-charging high-capacity button battery and its preparation method to solve the problems raised in the above-mentioned background technology.

In order to achieve the above object, the present invention provides the following technical solutions: a fast-charging high-capacity button battery, including a winding core, the winding core includes a diaphragm, the diaphragm is wound to form a spiral structure, and the spiral gaps of the diaphragm are fixed Attach the positive electrode sheet and the negative electrode sheet, the positive electrode sheet and the negative electrode sheet at the end of the diaphragm are fixedly connected to the tabs, the bottom and top of the outer wall of the core are respectively sleeved with a support ring and a sealing rubber ring, and the outer wall of the support ring is fixed. The positive electrode case is socketed, the top of the sealing rubber ring is fixedly connected to the flange cover, the flange cover is fixedly connected to the positive electrode case, and the two tabs are respectively electrically connected to the inner wall of the positive electrode case and the flange cover.

In a preferred embodiment, the positive electrode sheet is calculated by mass percentage, and its raw material composition includes: 92-97% of lithium cobaltate, 0.5%-2% of conductive agent A, 0.5%-2% of conductive agent B and viscose Binder A1%-3%, the negative electrode sheet is calculated by mass percentage, and its raw material composition includes: graphite 92-97%, conductive agent A0.5%-2%, binder B0.5%-2% and Thickener 1%-3%.

In a preferred embodiment, the positive electrode sheet is calculated by mass percentage, and its raw material composition includes: 95% of lithium cobaltate, 1.5% of conductive agent A, 1% of conductive agent B and 2.5% of binder A. The negative electrode The sheet is calculated by mass percentage, and its raw material composition includes: 94% of graphite, 2% of conductive agent A, 2% of binder B and 2% of thickener.

In a preferred embodiment, the positive electrode sheet is composed of 93% lithium cobaltate, conductive agent A2%, conductive agent B2% and binder A3%, and the negative electrode sheet is measured by mass percent. Calculated, its raw material composition includes: 96% of graphite, 1.5% of conductive agent A, 1% of binder B and 1.5% of thickener.

A preferred embodiment, the conductive agent A is carbon black conductive agent SP, the conductive agent B is carbon black conductive agent KS-6, the binder A is polyvinylidene fluoride PVDF, the bonding Agent B is styrene-butadiene rubber (SBR), and the thickener is sodium carboxymethylcellulose CMC.

A preparation method for a fast-charging high-capacity button cell, comprising the steps of:

S1, preparation of positive electrode sheet and negative electrode sheet

Production of positive electrode sheet: uniformly mix the main material lithium cobaltate, conductive agent ASP, conductive agent BKS-6, and binder APVDF according to the ratio, and use vacuum mixing and high-speed stirring process for positive electrode sheet mixing, coating and rolling Press to get the positive electrode sheet;

Production of negative electrode sheet: uniformly mix the main material graphite, conductive agent ASP, binder BSBR, and thickener CMC according to the ratio, and use vacuum mixing and high-speed stirring technology to carry out negative electrode sheet mixing, coating and rolling to obtain the negative electrode piece;

S2. Vacuum-dry the positive and negative electrodes in step S1 at 100-200°C for 2-12 hours to obtain the positive and negative electrodes before cutting;

S3. The positive and negative electrode sheets obtained in step S3 are wound with the diaphragm, pasted with high temperature glue, spot welded, covered with support rings, soaked, sealed and other processes to form a core, and the support ring structure is covered to prepare an uncharged bare button cells;

S4. The uncharged battery cell obtained in step S4 is processed through chemical formation, aging, and standing, and is equipped with a sealing rubber ring, a positive electrode case, and a flanged cover to prepare a battery with good voltage consistency, low internal resistance, and high capacity. High, support 3C fast charging button battery.

In a preferred implementation case, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the viscosity of the mixture is controlled to 5000-7000cps, and the rotation is 25±5r/min in the vacuum mixing and high-speed stirring process, and the revolution is 30±5r /min, vacuum degree -0.08Pa-1Pa.

In a preferred embodiment, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the raw materials are pretreated by conventional baking at 300-400°C, the dust degree is controlled at 15,000-25,000 pieces/cubic feet, and the coating speed is 3-10r/min.

Compared with the prior art, the beneficial effect of the present invention is: through the unique supporting ring battery structure, adopting the high-capacity fast-charging electrode piece with a unique formula, through the processes of winding, welding, soaking, sealing, aging, etc., Obtain a high-performance high-capacity fast-charging button battery, and the test shows that the present invention adopts a unique structure, a pole piece prepared by a unique formula, and the battery after assembly has low internal resistance, high capacity, supports fast charging and the method The method has the characteristics of simple process, low cost, easy operation and the like, and the prepared button battery has good consistency and can be mass-produced quickly.

Description of drawings

Fig. 1 is the explosion diagram of battery structure of the present invention;

Fig. 2 is the structure schematic diagram of winding core in the present invention;

Fig. 3 is the charge-discharge curve figure (3C charge) of the button battery prepared by the present invention;

Fig. 4 is the cycle performance curve figure of the button battery prepared by the present invention;

Fig. 5 is the voltage distribution diagram of the button battery prepared by the present invention;

Fig. 6 is an internal resistance distribution diagram of a button battery prepared in the present invention.

In the figure: 1. Positive electrode shell; 2. Support ring; 3. Rolling core; 31. Positive electrode sheet; 32. Negative electrode sheet; 33. Diaphragm; 34. Tab; 4. Sealing rubber ring;

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1

Please refer to Figures 1-6, the present invention provides a technical solution: a fast-charging high-capacity button battery, including a winding core 3, the winding core 3 includes a diaphragm 33, the diaphragm 33 is wound to form a spiral structure, and the spiral gap of the diaphragm 33 The positive electrode sheet 31 and the negative electrode sheet 32 are fixedly attached between them, the positive electrode sheet 31 and the negative electrode sheet 32 at the end of the diaphragm 33 are fixedly connected to the tabs 34, and the bottom and top of the outer wall of the winding core 3 are respectively sleeved with the support ring 2 and the sealing rubber ring 4, The outer wall of the support ring 2 is fixedly socketed to the positive electrode case 1, the top of the sealing rubber ring 4 is fixedly connected to the flanged cover 5, the flanged cover 5 is fixedly connected to the positive electrode case 1, and the two tabs 34 are electrically connected to the positive electrode case 1 and the flanged cover respectively 5 inner walls.

Further, in terms of mass percentage, the positive electrode sheet 31 comprises: 95% lithium cobaltate, 1.5% conductive agent A, 1% conductive agent B and 2.5% binder A, and the negative electrode sheet 32 is expressed in mass percentage, Its raw material composition includes: 94% of graphite, 2% of conductive agent A, 2% of binder B and 2% of thickener.

Further, conductive agent A is carbon black conductive agent SP, conductive agent B is carbon black conductive agent KS-6, binder A is polyvinylidene fluoride PVDF, and binder B is styrene-butadiene rubber (SBR), thickened The agent is sodium carboxymethylcellulose CMC.

A preparation method for a fast-charging high-capacity button cell, comprising the steps of:

S1, preparation of positive electrode sheet and negative electrode sheet

Production of positive electrode sheet: uniformly mix the main material lithium cobaltate, conductive agent ASP, conductive agent BKS-6, and binder APVDF according to the ratio, and use vacuum mixing and high-speed stirring process for positive electrode sheet mixing, coating and rolling Press to obtain the positive electrode sheet 31;

Production of negative electrode sheet: uniformly mix the main material graphite, conductive agent ASP, binder BSBR, and thickener CMC according to the ratio, and use vacuum mixing and high-speed stirring technology to carry out negative electrode sheet mixing, coating and rolling to obtain the negative electrode slice 32;

S2. Vacuum-dry the positive and negative electrodes in step S1 at 100-200°C for 2-12 hours to obtain the positive and negative electrodes before cutting;

S3. The positive and negative electrode sheets obtained in step S3 are wound with the separator 33, pasted with high-temperature glue, spot welding, covered with a support ring, soaked, sealed, etc. to form a core 3, and the structure of the support ring 2 is covered to prepare Uncharged bare button cell;

S4. The uncharged battery cell obtained in step S4 is processed by chemical formation, aging, standing, etc., and the sealing rubber ring 4, the positive electrode case 1 and the flange cover 5 are added, and the voltage consistency is good and the internal resistance is low. , High capacity, support 3C fast charging button battery.

In a preferred embodiment, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the viscosity of the mixture is controlled at 5000-7000cps, and the rotation is 25±5r/min in the vacuum mixing and high-speed stirring process, and the revolution is 30±5r/min , Vacuum degree -0.08Pa-1Pa.

In a preferred embodiment, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the raw materials are pretreated by conventional baking at 300-400°C, the dust degree is controlled at 15,000-25,000 pieces/cubic feet, and the coating speed is 3-10r/min.

Example 2

Please refer to Figures 1-6, the present invention provides a technical solution: a fast-charging high-capacity button battery, including a winding core 3, the winding core 3 includes a diaphragm 33, the diaphragm 33 is wound to form a spiral structure, and the spiral gap of the diaphragm 33 The positive electrode sheet 31 and the negative electrode sheet 32 are fixedly attached between them, the positive electrode sheet 31 and the negative electrode sheet 32 at the end of the diaphragm 33 are fixedly connected to the tabs 34, and the bottom and top of the outer wall of the winding core 3 are respectively sleeved with the support ring 2 and the sealing rubber ring 4, The outer wall of the support ring 2 is fixedly socketed to the positive electrode case 1, the top of the sealing rubber ring 4 is fixedly connected to the flanged cover 5, the flanged cover 5 is fixedly connected to the positive electrode case 1, and the two tabs 34 are electrically connected to the positive electrode case 1 and the flanged cover respectively 5 inner walls.

Further, the positive electrode sheet 31 is calculated by mass percentage, and its raw material composition includes: lithium cobaltate 93%, conductive agent A2%, conductive agent B2%, and binder A3%, and the negative electrode sheet 32 is calculated by mass percentage, and its raw material composition includes: : 96% of graphite, 1.5% of conductive agent A, 1% of binder B and 1.5% of thickener.

Further, conductive agent A is carbon black conductive agent SP, conductive agent B is carbon black conductive agent KS-6, binder A is polyvinylidene fluoride PVDF, and binder B is styrene-butadiene rubber (SBR), thickened The agent is sodium carboxymethylcellulose CMC.

A preparation method for a fast-charging high-capacity button cell, comprising the steps of:

S1, preparation of positive electrode sheet and negative electrode sheet

Production of positive electrode sheet: uniformly mix the main material lithium cobaltate, conductive agent ASP, conductive agent BKS-6, and binder APVDF according to the ratio, and use vacuum mixing and high-speed stirring process for positive electrode sheet mixing, coating and rolling Press to obtain the positive electrode sheet 31;

Production of negative electrode sheet: uniformly mix the main material graphite, conductive agent ASP, binder BSBR, and thickener CMC according to the ratio, and use vacuum mixing and high-speed stirring technology to carry out negative electrode sheet mixing, coating and rolling to obtain the negative electrode slice 32;

S2. Vacuum-dry the positive and negative electrodes in step S1 at 100-200°C for 2-12 hours to obtain the positive and negative electrodes before cutting;

S3. The positive and negative electrode sheets obtained in step S3 are wound with the separator 33, pasted with high-temperature glue, spot welding, covered with a support ring, soaked, sealed, etc. to form a core 3, and the structure of the support ring 2 is covered to prepare Uncharged bare button cell;

S4. The uncharged battery cell obtained in step S4 is processed by chemical formation, aging, standing, etc., and the sealing rubber ring 4, the positive electrode case 1 and the flange cover 5 are added, and the voltage consistency is good and the internal resistance is low. , High capacity, support 3C fast charging button battery.

In a preferred embodiment, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the viscosity of the mixture is controlled at 5000-7000cps, and the rotation is 25±5r/min in the vacuum mixing and high-speed stirring process, and the revolution is 30±5r/min , Vacuum degree -0.08Pa-1Pa.

In a preferred embodiment, in step S1, in the production of the positive electrode sheet and the negative electrode sheet, the raw materials are pretreated by conventional baking at 300-400°C, the dust degree is controlled at 15,000-25,000 pieces/cubic feet, and the coating speed is 3-10r/min.

Now carry out 3C charging and discharging experiment, cycle performance experiment, random sampling 100Pcs detection voltage distribution and random sampling 100Pcs detection internal resistance distribution to the battery prepared by the present invention, the results are shown in Fig. 3-6 respectively, according to the result display, its 3C charging The discharge performance is excellent, the charge capacity can still reach more than 95% after more than 100 cycles of use, the average value of the random voltage distribution reaches 3.975V, and the average value of the random internal resistance is only 269.3mΩ, which shows that the battery prepared by the present invention has good consistency and good internal resistance. Excellent performance of low resistance, high capacity, and support for fast charging.

In summary, the present invention adopts a unique supporting ring battery structure, adopts a high-capacity fast-charging pole piece with a unique formula, and obtains high-performance, high-capacity fast-charging electrodes through processes such as winding, welding, soaking, sealing, and aging. Type button battery, test shows, the present invention adopts unique structure, the pole piece of unique formula preparation, the battery after assembly, internal resistance is low, capacity is high, supports fast charging and this method has simple process, low cost, Easy to operate and other characteristics, and the button battery prepared at the same time has good consistency and can be mass-produced quickly.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. and modifications, the scope of the invention is defined by the appended claims and their equivalents.

Claims (8)

1. The utility model provides a fill type high capacity button cell soon, includes roll core (3), its characterized in that: roll up core (3) and include diaphragm (33), diaphragm (33) are convoluteed and are formed helical structure, fixed attached positive plate (31) and negative plate (32) between the helical gap of diaphragm (33), the equal fixed connection utmost point ear (34) of positive plate (31) and negative plate (32) at diaphragm (33) end, support ring (2) and sealed rubber ring (4) are cup jointed respectively to the outer wall bottom and the top of rolling up core (3), the outer wall fixed cup joint of support ring (2) is anodal shell (1), the top fixed connection turn-ups lid (5) of sealed rubber ring (4), turn-ups lid (5) fixed connection anodal shell (1), two the inner wall of anodal shell (1) and turn-ups lid (5) is connected to utmost point ear (34) electricity respectively.

2. The fast-charging high-capacity button battery according to claim 1, wherein the positive plate (31) comprises the following raw materials in percentage by mass: 92-97% of lithium cobaltate, 0.5-2% of conductive agent A, 0.5-2% of conductive agent B and 1-3% of binder A, wherein the negative plate (32) comprises the following raw materials in percentage by mass: 92-97% of graphite, 0.5-2% of conductive agent A, 0.5-2% of binder B and 1-3% of thickening agent.

3. The button cell of claim 2, wherein the positive plate (31) comprises the following raw materials in percentage by mass: 95% of lithium cobaltate, 1.5% of conductive agent A, 1% of conductive agent B and 2.5% of binder A, wherein the negative plate (32) comprises the following raw materials in percentage by mass: 94% of graphite, 2% of a conductive agent A, 2% of a binder B and 2% of a thickening agent.

4. The button cell of claim 2, wherein the positive plate (31) comprises the following raw materials in percentage by mass: 93% of lithium cobaltate, a conductive agent A2%, a conductive agent B2% and a binder A3%, wherein the negative electrode sheet (32) comprises the following raw materials in percentage by mass: 96% of graphite, 1.5% of conductive agent A, 1% of binder B and 1.5% of thickening agent.

5. A fast-charging type high-capacity button cell according to claim 2, characterized in that: the conductive agent A is a carbon black conductive agent SP, the conductive agent B is a carbon black conductive agent KS-6, the binder A is polyvinylidene fluoride (PVDF), the binder B is Styrene Butadiene Rubber (SBR), and the thickening agent is sodium carboxymethylcellulose (CMC).

6. A preparation method of a quick-charging type high-capacity button battery is characterized by comprising the following steps:

s1, preparation of positive plate and negative plate

Manufacturing a positive plate: uniformly mixing a main material (lithium cobaltate), a conductive agent A (SP), a conductive agent B (KS-6) and a binder A (PVDF) according to a ratio, and mixing, coating and rolling a positive plate by adopting a vacuum mixing high-speed stirring process to obtain a positive plate (31);

and (3) manufacturing a negative plate: uniformly mixing a main material (graphite), a conductive agent A (SP), a binder B (SBR) and a thickening agent (CMC) according to a ratio, and mixing, coating and rolling the negative plate by adopting a vacuum mixing high-speed stirring process to obtain a negative plate (32);

s2, carrying out vacuum drying on the positive and negative plates obtained in the step S1 at 100-200 ℃ for 2-12h to obtain the positive and negative plates before slitting;

s3, winding the positive and negative pole pieces obtained in the step S3 and a diaphragm (33), attaching high-temperature glue, spot welding, sleeving a support ring, soaking liquid, sealing and the like to form a winding core (3), sleeving the support ring (2) structure outside, and preparing an uncharged bare button cell;

and S4, adding a sealing rubber ring (4), a positive shell (1) and a flanging cover (5) to the uncharged cell obtained in the step S4 through technological processes of formation, aging, standing and the like to prepare the button cell which has good voltage consistency, lower internal resistance and higher capacity and supports 3C fast charging.

7. The preparation method of the fast-charging high-capacity button battery according to claim 6, characterized in that: in the step S1, in the manufacturing of the positive plate and the negative plate, the viscosity of the mixture is controlled to be 5000-7000cps, the mixture rotates 25 +/-5 r/min, revolves 30 +/-5 r/min and has a vacuum degree of-0.08 Pa-1Pa in the vacuum mixing high-speed stirring process.

8. The preparation method of the fast-charging high-capacity button battery according to claim 6, characterized in that: in the step S1, in the manufacture of the positive plate and the negative plate, the raw materials are pretreated by conventional baking at 300-400 ℃, the dust degree is controlled at 15000-25000 pieces per cubic foot, and the coating speed is 3-10r/min.

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