JP5591402B2 - Lithium battery electrode structure - Google Patents

Description

  The present invention relates to an electrode structure of a lithium battery, and particularly refers to forming a conductive electrode structure of a lithium battery by a covering and non-direct penetration method to achieve a sealing effect in a conductive portion of the electrode.

Lithium batteries can be used as a power supply source (eg, lithium iron phosphate secondary batteries) that require a large amount of electricity due to a significant leap in material technology. Used for equipment. This type of high-capacity non-aqueous electrolyte secondary lithium battery has a larger storage capacity and power supply than a conventional lithium battery. The battery can of the secondary lithium battery is usually a metal can made of aluminum.
Generally speaking, a metal can is made of aluminum or stainless steel, and is made into a cylindrical shape or a square shape with at least one open end. After sealing the positive electrode, negative electrode and separator of the battery in a metal can, the opening part of the battery can can be securely sealed with various sealing techniques with a cover plate in order to maintain long-term stable sealing inside the battery. Yes, it guarantees good waterproof and gas-proof performance of the battery.

  In the electrode of the existing prismatic lithium battery, electrode terminals that are electrically connected to the outside are provided on the cover plate, and the two are separated by an insulating plate. Further, the rivet passes through the lid plate, the positive electrode terminal, and the insulating plate, whereby the positive electrode terminal is fixed to the lid plate. In addition, an insulating plate is installed below the cover plate, and the rivet and the cover plate are insulated. An electrode connector is welded to the lower end of the rivet to connect the positive electrode connector and the positive electrode (or negative electrode) of the battery in the metal can.

  In a cylindrical battery, a conductive tab formed by integral molding or welding and a conductive terminal penetrating the cover plate are electrically connected to complete an application in external discharge.

  It should be noted that at present, the design of the electrode structure of the lithium battery connected from the battery inside the metal can to the outside of the cover plate is a system that penetrates the cover plate, and rigid rivets or bolts (conductive terminals) are used. External electrode. Through this type of lid penetration and the use of rigid materials, you may have the following defects:

  1. The electrode structure by the penetration method can achieve the sealing effect of this portion by the insulating plate. However, after using for a long time, when a rubber insulating plate is generally used, a gap may occur due to aging. At this time, the through-hole portion is not sealed again, and moisture may enter the inside of the metal can of the battery from this portion, and the service life of the battery is reduced.

  2. The external electrode of rigid material can be used in a high-vibration environment such as an electric bicycle or an electric wheelchair when two lithium batteries arranged side by side are connected in series or in parallel by an electric connection component. When used, the electrode through hole is broken and deformed by the relative stress of the rigid material, and the through hole portion is not sealed. Water may enter the inside of the battery metal can from this portion, and the service life of the battery will be reduced.

3. In the electrode structure by the penetration method, the cross-sectional area at the point where the portion (rivet or bolt (conductive terminal)) that penetrates the cover plate contacts the outside is not large. This type of structural principle is like a bridge that is incomparably small in a part of a spacious boulevard, that is, the more cars that pass through the bridge, the more easily traffic jams occur at the entrance of the bridge.
On the same principle, when a large amount of electrons pass through the electrode, the thermal energy may be generated due to the impedance of the portion penetrating the lid plate, so that the temperature may rise during charging. Due to the effect of the temperature rise, impedance is further induced to increase the vicious circle, and the safety of use is not preferable.
Furthermore, when a large amount of charge receives a voltage and passes through the electrode, the resistance of the electrode increases, and the charge / discharge efficiency naturally decreases.

  With respect to the electrode structure based on the existing penetration method, it is necessary to attach a part such as an insulating plate for sealing in order to penetrate the cover plate.

  In order to solve the above drawbacks, the present invention provides an electrode structure for a lithium battery. The conductive electrode structure of a lithium battery is formed by a non-direct penetration method, and water does not easily enter the metal can of the battery, and easily reaches the sealing standard in the conductive part of the electrode.

  Another object of the present invention is to design an elastic contact electrode structure, so that even when used in a high-vibration environment, the electrode is not easily broken or deformed at the lead-out portion of the cover plate, and the service life of the battery is extended.

  Another object of the invention is to increase the contact area outside the electrode and adapt it for high current applications. Reduces the effect of electrode resistance, increases safety in high current applications, and increases the charge / discharge efficiency of lithium batteries.

  Another object of the present invention is to simplify the sealing structure of the electrode and the cover plate. Although it is simple in structure and reaches the sealing standard, its manufacturing difficulty and cost are lower than existing technology.

To achieve the above object, the present invention discloses a lithium battery electrode structure. It is an electrode structure that electrically connects the positive and negative electrodes of the battery in the can of the lithium battery to the outside, using an insulating waterproof material, and a lid plate body that is integrally molded by an injection molding method, and at least one metal material Includes an electrode body. An intermediate portion of the electrode body is a covering portion, and the covering portion is provided in the lid plate body.
In addition, a first bent portion is formed at one end of the covering portion, and the first bent portion is formed by extending a connecting portion that appears from the lower surface of the lid plate body, and the positive electrode (or negative electrode) of the battery in the can body Connect electrically. A second bent portion is formed at the other end of the covering portion, and the second bent portion appears from the upper surface of the lid plate body, and an output portion that conducts externally is stretched.

  Among these, this output part forms a 3rd bending part, and a contact part is extended and formed from this 3rd bending part.

  Among these, at least one fixing component is provided on the upper surface of the lid plate main body, and the fixing component can form a non-contact state or a contact state with the covering portion of the electrode main body when installed.

The advantages of the present invention are as follows.
In addition to the sealing effect formed by the covering, the electrode body covering portion and the first and second bent portions are formed inside the lid plate body. An exposed form is formed. Due to the bent form, even if water intrudes from the seam portion, the path is extended and it is prevented from entering the inside of the lithium battery can by capillary action.
Furthermore, since the electrode body is plate-shaped, a large contact area can be formed outside by the contact part formed by extending the third bent part, and when a large amount of electric charge passes through the electrode under voltage The resistance of the electrode is lowered, and the charge / discharge efficiency is improved.
Furthermore, since the anti-vibration effect is formed by the third bent portion, the breakage and deformation generated in the electrode on the cover plate due to the relative stress of the known rigid material are reduced, and the service life of the lithium battery is extended. Unlike the electrode structure with the well-known penetration method, the sealing structure of the electrode and the cover plate is simplified, so that the standard of sealing can be reached without the need for extra sealing parts, and the manufacturing difficulty and cost are increased. Lower than disclosed technology.

FIG. 1 is a three-dimensional schematic diagram of the first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of the first embodiment of the present invention. FIG. 3 is a schematic diagram of another application in the first embodiment of the present invention. FIG. 4 is a three-dimensional schematic diagram of the second embodiment of the present invention. FIG. 5 is a schematic sectional view of a second embodiment of the present invention. FIG. 6 is a schematic diagram of another application in the third embodiment of the present invention.

  The detailed description and technical description of the present invention will now be further described by way of examples. It should be understood, however, that these examples are merely used to illustrate the description and should not be construed as limiting the practice of the present invention.

Please refer to FIG. 1 and FIG. FIG. 1 and FIG. 2 are solid and cross-sectional schematic views of the first embodiment of the present invention. A rectangular lithium battery will be described as an example.
It is necessary to electrically connect the positive electrode and the negative electrode of the battery in the can 300 of the lithium battery to the outside, and the general rectangular lithium battery has an electrode body 200 made of a plate-like metal material on the lid plate body 100. Are electrically connected to the positive electrode and the negative electrode (not shown) of the battery in the can 300. An intermediate portion of each electrode body 200 is a covering portion 210, and the covering portion 210 is provided in the lid plate body 100. A first bent portion 201 is formed at one end of the covering portion 210, and the first bent portion 201 extends to form a connecting portion 220 that appears from the lower surface 101 of the lid plate body 100, and the connecting portion 220 and the can It is electrically connected to the positive electrode (or negative electrode) of the battery in the body 300.
A second bent portion 202 is formed at another end of the covering portion 210, and the second bent portion 202 extends to form an output portion 230 that appears from the upper surface 102 of the lid plate main body 100, thereby the output Part 230 conducts externally. Further, a third bent portion 203 is formed at one end of the output portion 230, and a contact portion 240 used for contact application when electrically connecting to the outside is extended from the third bent portion 203. .

  In implementation, the lid plate body 100 is integrally molded by an injection molding method using an insulating waterproof material. Any known material and method can be employed, for example, formed by injection molding using a plastic material.

  In practice, any known method can be employed to prevent light from passing through the lid body 100 and irradiating the inside of the can body 300 and damaging the chemical material inside the can body 300. For example, a metal plate is provided in the lid plate main body 100 to increase physical strength and light shielding, or a light shielding material is attached or applied to the lid plate main body 100.

  The electrode body 200 can employ any known conductive metal material, for example, a commonly used metal material such as copper or aluminum. The covering portion 210 and the first and second bent portions 201 and 202 of the electrode body 200 are formed inside the lid plate body 100. In practice, in addition to the sealing effect formed by the covering, the first and second bent portions 201 and 202 form a form in which the electrode body 200 is exposed through the cover plate body 100 in a non-directly penetrating manner. The first and second bent parts 201 and 202 can extend the path even if the water leaks from the exposed seam, and the water penetrates into the inside of the lithium battery can 300 by capillary action. To prevent.

In addition to the fact that a large contact area can be formed outside by the contact part 240 formed by extension by the third bent part 203, when the large amount of charge receives the voltage and passes through the electrode body 200, the electrode body The resistance at the contact surface with the outside of 200 can be reduced, and the efficiency of charging and discharging is improved.
Further, since the electrode body 200 is formed of a plate-like metal material, the third bent portion 203 has the third bent portion 203 as a fulcrum due to the elastic effect inherent in the plate-like metal, and the contact portion. When 240 is connected to the outside, it has an upper and lower buffering effect. The contact portion 240 forms an external contact point having an anti-vibration effect, and the breakage and deformation generated in the electrode due to the relative stress of a well-known rigid material are reduced, thereby extending the service life of the lithium battery.

See further FIG. In implementation, for example, when two or more lithium batteries are connected in series or in parallel by electrical connection components, the fixed component 400 may be provided on the upper surface 102 of the lid plate main body 100 due to demand for fixation.
In practice, when the lid plate main body 100 is integrally molded, the sealing portion 401 of the fixing component 400 can be covered in the lid plate main body 100 and fixed from the upper surface 102 of the lid plate main body 100. When the portion 402 is exposed and connected in series or in parallel, or when a lithium battery is connected, it is convenient to connect firmly by the fixing portion 402.
In practice, the fixing part 400 may be formed below the contact portion 240, and based on the thickness factor of the lid plate body 100, the fixing part 400 may be formed inside the lid plate body 100 during manufacturing. The sealing portion 401 and the covering portion 210 may be in a non-contact state or a contact state.

  As a result, the fixed component 400 is not directly connected to the electrodes as in the existing technology. Even if the fixed component 400 is used in a high vibration environment such as an electric bicycle and an electric wheelchair, The connection relationship between the main body 200 and the lid plate main body 100 is not broken.

See also FIGS. 4 and 5. 4 and 5 are three-dimensional and cross-sectional schematic views of the second embodiment of the present invention. An example in which the present invention is applied to a cylindrical lithium battery will be described. Since the electrodes of a general cylindrical lithium battery are respectively conductive from both ends, the lid plate body 500 has one electrode body 600 made of a plate-like metal material, and the positive electrode or negative electrode ( (Not shown) and electrically connected. An intermediate portion of the electrode body 600 is a covering portion 610. The covering portion 610 is provided in the lid body 500, and first and second bent portions 601 and 602 are formed at both ends of the covering portion 610, respectively. .
The first bent portion 601 extends the connection portion 620 that appears from the lower surface 501 of the lid plate body 500 and is used for electrical connection with the positive electrode (or negative electrode) of the battery in the can 700. The second bent portion 602 appears from the upper surface 502 of the lid plate body 500 and extends to form an output portion 630 that conducts externally. A third bent portion 603 is formed at one end of the output portion 630, and a contact portion 640 that can be used for contact application when electrically connecting to the outside is extended from the third bent portion 603. The

  As in the first embodiment, the lid main body 500 uses an insulating waterproof material and is integrally formed by an injection molding method, and any known material and method can be adopted. Any known method can be employed to prevent light transmission, for example, by providing a metal plate within the lid plate body 500 to increase physical strength and light protection, or to the lid plate body 500. Apply or apply light-proofing material.

  Similarly to the description of the first embodiment, the electrode main body 600 can employ any known conductive metal material, for example, a commonly used metal material such as copper or aluminum.

See further FIG. In implementation, for example, when two or more lithium batteries are connected in series or in parallel by electrical connection components, a fixed component 800 may be provided on the upper surface 502 of the lid plate main body 500 due to demand for fixation. The cover plate 500 is covered with the sealing portion 801 of the fixed component 800, and the fixed portion 802 is exposed from the upper surface 502 of the cover plate main body 500.
In actual manufacturing, the sealing portion 801 and the covering portion 610 inside the lid plate main body 500 may be in a non-contact state or a contact state. In a general cylindrical lithium battery, the fixed part 800 is provided at the center of the upper surface 502 of the lid body 500 and is formed below the contact portion 640, and the cylindrical lithium batteries are connected in series. Or it is convenient to use in parallel connection.

  The above description is only a preferred embodiment of the present invention, and the scope of the present invention cannot be limited thereby. That is, all simple equivalent changes and modifications made based on the scope of protection filed in the present invention and the description of the invention belong to the scope of the claims of the present invention.

DESCRIPTION OF SYMBOLS 100 Lid plate main body 500 Lid plate main body 101 Lower surface 501 Lower surface 102 Upper surface 502 Upper surface 200 Electrode main body 600 Electrode main body 201 1st bending part 601 1st bending part 202 2nd bending part 602 2nd bending part 203 3rd bending part 603 3rd bending part 210 Cover part 610 Cover part 220 Connection part 620 Connection part 230 Output part 630 Output part 240 Contact part 640 Contact part 300 Can body 700 Can body 400 Fixed part 800 Fixed part 401 Sealing Wearing part 801 Sealing part 402 Fixing part 802 Fixing part

Claims (5)

The electrode structure of the lithium battery, which is an electrode structure for electrically connecting the positive electrode and the negative electrode of the battery in the can of the lithium battery to the outside,
The lid body,
An electrode body made of at least one plate-shaped metal material,
An intermediate part of the electrode body is a covering part, the covering part is provided in the lid plate body, a first bent part is formed at one end of the covering part, and the first bent part is the lid. A connecting portion that appears from the lower surface of the plate body is stretched, a second bent portion is formed at another end of the covering portion, and an output portion that appears from the upper surface of the lid plate main body is formed. stretched form, the cover plate body, Ru is integrally molded by injection molding method using the insulating waterproof material, the electrode of a lithium battery.   The electrode structure according to claim 1, wherein a third bent portion is formed at the output portion, and a contact portion is extended from the third bent portion.   The electrode structure according to claim 1, wherein at least one fixing component is provided on an upper surface of the lid plate main body. The electrode structure according to claim 3 , wherein the fixed part and the covering portion of the electrode main body are in a non-contact state. The electrode structure according to claim 3 , wherein the fixed part and the covering portion of the electrode main body are in contact with each other.

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