CN212587559U

CN212587559U - Button lithium battery roll core and button lithium battery comprising same

Info

Publication number: CN212587559U
Application number: CN202021668610.6U
Authority: CN
Inventors: 黄德勇; 王世芳; 柳振漫; 冯浩
Original assignee: O'cell New Energy Technology Co ltd
Current assignee: O'cell New Energy Technology Co ltd
Priority date: 2020-08-12
Filing date: 2020-08-12
Publication date: 2021-02-23
Anticipated expiration: 2030-08-12

Abstract

The utility model provides a button lithium battery roll core, which comprises a roll core, a positive electrode lug and a negative electrode lug, wherein the roll core is a flat square formed by hot pressing after a diaphragm is wound, the positive electrode lug and the negative electrode lug are inserted at two ends of the roll core, and at least one layer of diaphragm is arranged between the positive electrode lug and the negative electrode lug; the utility model also provides a button lithium battery, set up insulating seal ring between closing up including negative pole lid, positive pole shell, negative pole lid outer fringe and positive pole shell, pack electrolyte in the positive pole shell, set up through fixed subassembly is fixed in the positive pole shell the button lithium battery rolls up the core, and the negative pole ear welds with the negative pole lid; the utility model discloses an improve button lithium cell's roll core structure and shaping mode for traditional button battery can charge used repeatedly many times, has realized button battery's secondary charging and has used, has avoided primary battery to frequently abandon the environmental pollution who causes.

Description

Button lithium battery roll core and button lithium battery comprising same

Technical Field

The utility model relates to a button cell technical field especially relates to a button lithium cell rolls up core and contains its button lithium cell.

Background

A button cell (button cell) is also called a button cell, and refers to a cell with an external dimension like a small button, which generally has a larger diameter and a thinner thickness. The button cell is widely applied to various miniature electronic products due to small body size, the diameter is from 4.8mm to 30mm, and the thickness is from 1.0mm to 7.7 mm; the back-up power supply is generally used for various electronic products, such as computer mainboards, electronic watches, electronic dictionaries, electronic scales, remote controllers, electric toys, cardiac pacemakers, electronic hearing aids, counters, cameras and the like.

The button cell comprises a positive electrode, a negative electrode, electrolyte and the like. The surface of the electrolyte tank is made of stainless steel materials and serves as a positive electrode, a negative electrode of the electrolyte tank is a stainless steel circular cover, a sealing ring is arranged between the positive electrode and the negative electrode and is insulated, the sealing ring is made of nylon, and the sealing ring can play an insulating role and also can prevent electrolyte from leaking. Button cells are in a wide variety, and most of them are named after the materials used, such as silver oxide cells, lithium manganese cells, alkaline manganese cells, and the like.

Common button cells are composed of carbon, alkaline, zinc-silver oxide, lithium-manganese dioxide and the like. Carbon button batteries are the most common and the least expensive, and alkaline button batteries have good discharge effect. Both voltages are around 1.5V, with nominal capacities varying from about 15mAh to 140 mAh. Is suitable for microampere-level discharge requirements. It is used in calculator, electronic toy, hearing aid, lighter, watch, etc.

The zinc-silver oxide button cell has the voltage of 1.55V and the capacity higher than that of carbon, and is mainly used for calculators, hearing aids, cameras, watches and the like. Particularly, the battery has good liquid leakage prevention effect and good long-term use effect.

The lithium manganese battery adopts a button battery, the voltage is about 3.0V, the combined battery pack is small and exquisite, but the discharge intensity is not large, the lithium manganese battery is mainly used for small motors, a direct-current power supply for small radio emission, and under the general condition, the lithium metal battery is a disposable lithium battery, has long continuous discharge time and is convenient to use. The battery has certain harm to the environment, and the battery needs to be effectively recycled.

In summary, button cells have the advantages of small size and long service life, but button cells have the disadvantage of being disposable.

SUMMERY OF THE UTILITY MODEL

Not enough to exist among the prior art, the utility model provides a button lithium cell rolls up core has solved the button lithium cell that exists among the prior art and can not charge used repeatedly's technical problem.

According to the utility model discloses an embodiment, button lithium cell rolls up core, including rolling up core, anodal ear and negative pole ear, roll up the flat square that core formed through hot pressing after rolling up by the diaphragm, anodal ear with the negative pole ear peg graft in roll up the both ends of core and the at least one deck diaphragm in the two interval.

According to a preferred embodiment of the utility model, the thickness of the formed roll core is 4.35mm-4.4 mm; the width of the roll core is 24mm-25 mm; the height of the roll core is 24mm-25 mm.

According to the utility model discloses a preferred embodiment, roll up the core and stereotype the back, resistance > 10M omega during direct current 250V.

According to a preferred embodiment of the present invention, the membrane is a PP stretch film, and the porosity of the membrane is 35% to 44%.

According to a preferred embodiment of the invention, the air permeability of the membrane is 300sec/100 mL.

According to the utility model discloses a preferred embodiment, positive tab is 0.1mm 3mm aluminium utmost point ear.

According to a preferred embodiment of the present invention, the negative electrode tab is a 0.05mm x 3.5mm nickel electrode tab.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model discloses an improve button lithium cell's roll core structure and shaping mode for traditional button battery can charge used repeatedly many times, has realized button battery's secondary charging and has used, has avoided primary battery to frequently abandon the environmental pollution who causes.

The utility model also provides a button lithium cell, set up insulating seal ring between binding off on negative pole lid, positive pole shell, negative pole lid outer fringe and the positive pole shell, pack electrolyte in the positive pole shell, through the fixed setting of fixed subassembly in the positive pole shell the button lithium cell rolls up core, negative pole ear and negative pole lid welding.

And the packaging method of the button lithium battery can finish sealing when the internal vacuum degree of the battery reaches 0.085 Mpa.

Compared with the prior art, the utility model discloses well button lithium cell adopts vacuum process to encapsulate the lithium cell, and lithium ion battery's vacuum seal technology is before the battery shaping, earlier with the inside vacuum environment who forms certain pressure of battery, behind the inside production gas of battery, the pressure can be partly consumed by the vacuum environment in the battery to reach the purpose that reduces the pressure intensity in the battery, after the interior pressure reduction of battery, also can corresponding step-down to battery seal structure's influence, thereby lithium ion battery's security has been promoted.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is an enlarged view of a portion a in fig. 1.

Fig. 3 is a schematic diagram of an internal structure of an embodiment of the present invention.

Fig. 4 is a schematic perspective view of an embodiment of the present invention.

In the above drawings: 10. a negative electrode cover; 20. a positive electrode case; 30. a seal ring; 40. a fixing assembly; 41. a fixing sheet; 42. A fixing leg; 50. a winding core; 51. a negative tab; 52. and a positive tab.

Detailed Description

The technical solution of the present invention will be further explained with reference to the accompanying drawings and embodiments.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the description of the present invention, the technical solutions between the embodiments can be combined with each other, but it must be based on the realization of the ordinary skilled person in the art, and when the technical solutions are combined and contradictory or can not be realized, it should be considered that the combination of the technical solutions does not exist, and the present invention is not within the protection scope claimed in the present invention.

A lithium ion battery is a secondary battery (rechargeable battery) that mainly operates by movement of lithium ions between a positive electrode and a negative electrode. In the process of charging and discharging, Li + is inserted and extracted back and forth between the two electrodes, wherein during charging, Li + is extracted from the positive electrode and inserted into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge.

Lithium ion batteries are used for mobile phones and notebook computers, and generally adopt materials containing lithium elements as electrodes, which are representative of modern high-performance batteries. According to different material systems of the lithium ion battery, the lithium ion battery is divided into ternary systems, lithium cobaltate systems, lithium iron phosphate systems, lithium manganate systems and the like, and the voltage and energy density of each system are different, so that the system has advantages and disadvantages. Lithium ion batteries are further classified into aluminum-can batteries, cylindrical batteries, polymer batteries, laminated batteries, and the like according to the shape and the manufacturing process of the batteries. The use fields of different types of batteries are different, and the use of the batteries is also different.

The voltage of the lithium ion battery is different due to the change of the anode material, the full-charge voltage of lithium cobaltate, lithium manganate and lithium manganate is generally 4.2V, the rated voltage is 3.7V, the full-charge voltage of the lithium iron phosphate battery is 3.65V, and the rated voltage is 3.2V. Compared with two types of batteries, the former battery has relatively higher energy density, and the former battery emits more energy under certain volume and mass conditions. But the lithium iron phosphate battery has better relative cycle performance, lithium cobaltate, ternary lithium manganate and lithium manganate batteries can generally reach 300-500 weeks, and lithium iron phosphate can reach more than 2000 times. The safety performance of the lithium iron phosphate battery is incomparable with other system batteries.

The lithium ion battery has high energy density and high average output voltage. Small self-discharge, good battery, below 2% per month (recoverable). There is no memory effect. The working temperature range is-20 ℃ to 60 ℃. Excellent cycle performance, rapid charge and discharge, high charging efficiency up to 100%, and high output power. The service life is long. Contains no toxic and harmful substances, and is called green battery.

Lithium ion batteries have many advantages, but there are some problems that need special attention:

a. the lithium ion battery can not be overcharged and overdischarged, the electric energy stored in the lithium battery is realized by electrochemical reversible chemical change, and the chemical change can be irreversibly reacted due to excessive charging and discharging, so that the performance of the battery is invalid. Therefore, when in use, the lithium ion battery is required to be used together with the corresponding lithium ion battery charging and discharging protection plate. The larger module also needs to add many other accessories, such as auxiliary control modules like BMS, temperature control, etc.

b. When the lithium ion battery is used and produced, because a chemical reaction exists during charging and discharging, and some unavoidable side reactions also exist, some gases are generally generated inside the lithium ion battery, when the polymer battery is produced, the gases are extracted to form a vacuum environment inside the battery, but on other types of lithium ion batteries, the operation cannot be realized temporarily, so that the inside of part of the battery is in a positive pressure state, in order to deal with the positive pressure, some components need to be added on the battery structure to eliminate the explosion risk caused by the positive pressure of the battery, the conventional explosion-proof component has a cylindrical CID cover cap, a pressure release valve of an aluminum-shell battery and the like, and because of the existence of the components, the volume and the quality of the battery cannot be lightened continuously.

c. Compared with the conventional battery, the lithium ion battery has much higher energy density, which is the advantage of the lithium ion battery and has certain hidden danger, and when the battery is used, if the battery is in short circuit, damaged and other abnormalities, the battery can instantly emit larger energy, so that the danger degree is higher. Therefore, the later protection of the lithium ion battery is very important, and similarly, special protection can be performed on the battery against possible problems during design, and the later protection of the lithium ion battery is another factor that the battery cannot be lightened.

By combining the current technology of the button cell and the current technology of the lithium ion battery, the advantages of the two products are combined together, and the button type lithium ion battery is designed and manufactured.

As shown in fig. 1-4, an embodiment of the present invention provides a button lithium battery, including a negative electrode cover 10, a positive electrode shell 20, an insulating sealing ring 30 disposed between an outer edge of the negative electrode cover 10 and an upper closing-in of the positive electrode shell 20, an electrolyte filled in the positive electrode shell 20, a winding core 50 fixedly disposed in the positive electrode shell 20 through a fixing assembly 40, the fixing assembly 40 including a fixing sheet 41 for fixing the winding core 50 and at least two fixing legs 42 connected to two ends of the fixing sheet 41, wherein the winding core 50 is obtained by a following forming method;

the forming method of the winding core comprises the following steps:

s1 winding, inserting nickel negative electrode tab 51 with thickness and width of 0.05mm and 3.5mm into one end of the separator after the separator is wound at least 1.5 times; then, after at least 1 circle of winding is continuously carried out, an aluminum positive lug 52 with the thickness and the width of 0.1mm and the width of 3mm is inserted into the other end of the diaphragm, and finally, a roll core 50 is fastened by adhesive paper with the thickness and the width and the length of 0.03 and 11 and 10 mm;

s2, shaping, namely, carrying out hot pressing on the fastened cylindrical winding core 50 to shape the winding core 50 into a flat square;

wherein, the thickness of the formed roll core is 4.35mm-4.4 mm; the width of the roll core is 24mm-25 mm; the height of the winding core is 24mm-25 mm; the porosity of the diaphragm is 35-44%, the air permeability of the diaphragm is 300sec/100mL, and the resistance value is larger than 10M omega when the direct current is 250V after the winding core is shaped;

roll up core 50 and block after the shaping, roll up core 50 and go into in the fixed subassembly 40, specifically roll up core 50 and compress tightly in stationary blade 41 below, anodal ear with stationary blade fixed connection, then use with the same 0.1mm PET gasket insulation battery negative pole lid 10 of size of anodal shell internal diameter, adopt resistance welding to weld negative pole ear 51 and negative pole lid 10.

After the battery is assembled, a special structure with an outer circle and an inner square is formed, the winding core 50 with the structure can be stably fixed in the positive electrode shell, the winding core 50 and the positive electrode shell are convenient to weld and fix, and the square winding core 50 and the circular positive electrode shell are matched to form four cavities with equal position distribution, so that electrolyte can be conveniently contained; the winding core 50 is formed and fixed in the positive electrode shell, the whole body and the coil core are placed in a vacuum box to be baked, and the battery is dewatered; after dewatering, a liquid injection pump is used for injecting liquid into the battery, the liquid injection amount is 50% more than that of a disposable button battery with the same model, the full winding core electrolyte is ensured, then the battery is subjected to vacuum sealing, the battery is sealed when the vacuum degree reaches 0.085Mpa or below, a negative pressure state can be formed inside the battery by adopting the vacuum sealing, and the positive pressure generated in the production and manufacturing process of the battery is counteracted by utilizing the negative pressure inside the battery, so that a stable state is formed; and finally, activating the battery according to the conventional activation process of the lithium ion battery.

The lithium ion battery is a device for realizing mutual conversion between chemical energy and electric energy, and the main reaction of the lithium ion battery is as follows: during charging: LiFePO4 → Li1-xFePO4+ xLi + + xe-when discharging: li1-xFePO4+ xLi + + xe- → LiFePO, inevitable moisture remains in the manufacturing process of the lithium battery, in the actual production process of the battery, a certain amount of moisture can be intentionally reserved in the lithium ion battery, the moisture is more beneficial to an SEI film with a more stable battery stroke, and the SEI film is formed by the fact that an electrode material and an electrolyte react on a solid-liquid phase interface to form a passivation layer covering the surface of the electrode material in the first charge and discharge process of the lithium ion battery. The passivation layer is an interface layer and has the characteristics of a solid electrolyte, the SEI film has insolubility of an organic solvent and can stably exist in an organic electrolyte solution, and solvent molecules cannot pass through the passivation layer, so that the co-intercalation of the solvent molecules can be effectively prevented, and the cycle performance and the service life of the electrode are greatly improved. The water in the battery can react with the simple substance lithium to generate gas, the water can react with the lithium hexafluorophosphate in the electrolyte to generate hydrogen fluoride, the hydrogen fluoride can continuously corrode the current collector to continuously generate other gases, and the gas components are complex

In the process of forming the lithium ion battery, a part of gas is required to be generated in the battery, internal pressure of the battery is caused due to the existence of the gas, a certain influence is formed on a sealing structure of the battery after the internal pressure of the battery exists, the internal pressure of the battery can influence the bearing pressure of a sealing structure of the battery to be increased, and the abnormal conditions of pressure relief and explosion of the battery can be caused after the internal pressure of the battery is continuously increased under certain conditions.

The utility model discloses in adopt vacuum process to encapsulate the lithium cell, lithium ion battery's vacuum seal technology, be before the battery shaping, earlier with the inside vacuum environment who forms certain pressure of battery, behind the inside production gas of battery, the pressure can be partly consumed by the vacuum environment in the battery to reach the purpose that reduces the pressure intensity in the battery, after the interior pressure reduction of battery, also can corresponding step-down to battery seal structure's influence, thereby lithium ion battery's security has been promoted.

The utility model discloses an improve button lithium cell's the technology of sealing, verified lithium ion battery vacuum packaging's feasibility, provide new encapsulation thinking for cylindrical and aluminum hull lithium ion battery's encapsulation, improved lithium ion battery security.

The utility model discloses the button type lithium battery capacity of production can reach 200mAh, and nominal voltage is 3.2V, can relapse 1000 times and charge and discharge and use.

It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein; any reference sign in a claim should not be construed as limiting the claim concerned.

Finally, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the present invention can be modified or replaced by other means without departing from the spirit and scope of the present invention, which should be construed as limited only by the appended claims.

Claims

1. Button lithium cell rolls up core, its characterized in that: including rolling up core, anodal ear and negative pole ear, roll up the flat square that core is formed by the diaphragm through hot pressing after rolling up, anodal ear with the negative pole ear peg graft in roll up the both ends of core and the two at least one deck diaphragm of interval.

2. The button lithium battery jelly roll of claim 1, wherein: the thickness of the roll core is 4.35mm-4.4 mm; the width of the roll core is 24mm-25 mm; the height of the roll core is 24mm-25 mm.

3. The button lithium battery jelly roll of claim 1, wherein: after the winding core is shaped, the resistance value is larger than 10M omega when the direct current is 250V.

4. The button lithium battery jelly roll of claim 1, wherein: the diaphragm is a PP tensile film, and the porosity of the diaphragm is 35% -44%.

5. The button lithium battery jelly roll of claim 1, wherein: the air permeability of the membrane was 300sec/100 mL.

6. The button lithium battery jelly roll of claim 1, wherein: the positive electrode tab is a 0.1mm 3mm aluminum tab, and the negative electrode tab is a 0.05mm 3.5mm nickel tab.

7. Button lithium cell sets up insulating seal ring between closing up on negative pole lid, positive pole shell, negative pole lid outer fringe and the positive pole shell, packs electrolyte, its characterized in that in the positive pole shell: the button lithium battery winding core according to any one of claims 1 to 6 is fixedly arranged in the positive shell through a fixing assembly, and the negative tab is welded with the negative cover.

8. The button lithium battery of claim 7, wherein: the fixing assembly comprises a fixing piece and at least two fixing feet, wherein the fixing piece is fixed with the roll core, the fixing feet are connected to two ends of the fixing piece, and the positive lugs are fixedly connected with the fixing piece.