WO2010072156A1

WO2010072156A1 - Battery and manufacturing method thereof

Info

Publication number: WO2010072156A1
Application number: PCT/CN2009/075932
Authority: WO
Inventors: 王伟强; 张性双; 邹晓兵; 王驰伟; 马振德
Original assignee: 深圳市比克电池有限公司
Priority date: 2008-12-24
Filing date: 2009-12-24
Publication date: 2010-07-01
Also published as: CN101764267A

Abstract

A battery and a manufacturing method thereof are provided. The battery includes a shell and a battery cell which is sealed in the shell and has a positive outlet terminal and a negative outlet terminal, the shell includes a rigid substrate and a soft composite plate, the substrate connects with the composite plate to form a sealed cavity for holding the battery cell, the battery cell is provided in the cavity, and the substrate generally is a metal plate. The metal substrate, as a part of the shell, not only has a high anti-explosion safety performance of the flexible packaging cell, but also improves the mechanical strength of the shell, and the safety of the battery in the use and manufacturing process is improved because the battery shell is not easily punctured; also the production cost of the battery is reduced because the production cost of the metal plate is low relative to the composite plate.

Description

Battery and manufacturing method

Technical field

The present invention relates to a battery and a method of manufacturing the same. Background technique

In a lithium ion battery, in addition to the positive and negative electrodes, the electrolyte, and the separator paper, a housing that stores various reaction components of the lithium ion battery is also a very important component. As an effective component, in addition to providing storage functions, the housing also provides electrode extraction for lithium-ion batteries, while also providing some help for the safety of lithium-ion batteries.

At present, the materials used in the battery casing are mainly: stainless steel, nickel-plated steel, aluminum alloy and aluminum plastic film. The aluminum plastic film has the characteristics of softness and softness. Therefore, the battery using the aluminum plastic film as the casing is a soft packaging battery, and has been highly valued for its superior safety in terms of explosion prevention. Aluminum plastic film, also known as aluminum-plastic composite film, is a flexible packaging battery prepared by cutting a piece of aluminum-plastic composite film of a certain size, folding aluminum-plastic composite film, and high-temperature compounding the opening edge of the aluminum-plastic composite film to make the battery pole The group is sealed inside and the like is completed. Aluminum-plastic composite film is generally made of multi-layer composite of PP and aluminum foil. Its mechanical strength is low, and it is easy to be pierced by sharp materials during manufacturing and use, resulting in safety hazard due to scrapping or scratching. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to solve the above technical problems and to provide a battery having a high mechanical strength and a method of manufacturing the same.

The object of the invention is achieved by the following technical solutions:

A battery comprising a housing and a battery unit sealed therein having a positive electrode lead end and a negative electrode lead end, the case comprising a substrate and a composite plate, the substrate being connected with the composite plate to form a closed cavity for accommodating the battery unit The battery unit is located in the closed cavity.

The composite panel may be a layered composite panel having at least one layer of metal, and the substrate may be a metal panel. The substrate can be joined to the composite panel by heat fusion. The hot melt layer can be polypropylene or polypropylene.

The cross section of the composite panel may be c-shaped, and the substrate is joined to the periphery of the composite panel to form the closed cavity.

The positive electrode terminal and the negative electrode terminal of the battery unit are taken out from the junction of the substrate and the composite plate. The composite plate may be an aluminum-plastic composite film. The substrate may be an aluminum plate, a steel plate, an aluminum foil or a copper foil. The battery can be a lithium ion battery.

A battery manufacturing method includes the following steps:

a component preparation step of preparing a battery unit having an electrode lead end, cutting a substrate having a thin plate structure, and a composite plate having a layered structure;

a chamber preparation step of stamping the composite sheet to form a cavity having a peripheral edge and accommodating the battery unit;

a battery unit mounting step, placing a battery unit into the cavity such that an electrode terminal end of the battery unit protrudes beyond the periphery;

In the packaging step, the periphery of the composite board is connected to the substrate such that the battery terminal is fixed between the substrate and the periphery of the composite board, so that the battery unit is packaged inside the cavity.

The packaging step may further include forming a liquid injection channel at a junction of the substrate and the layered composite panel, injecting the electrolyte into the cavity through the liquid injection channel, and closing the liquid injection channel.

The cavity preparation step may further include: forming a second cavity by stamping the layered composite plate; the packaging step further comprises forming a liquid injection channel and a second liquid injection channel at a junction of the substrate and the layered composite plate, The liquid injection channel communicates with the cavity and the second cavity, and the second liquid injection channel communicates with the second cavity and the outside, and the electrolyte is injected into the cavity through the second injection channel, the second cavity, and the injection channel, and then The injection channel and the second injection channel are closed.

The packaging step can also include charging the battery, discharging gas from the chamber through the liquid injection channel to the second cavity, closing the liquid injection channel, and cutting the second cavity.

A battery comprising a housing and a battery unit sealed in the housing and having an electrode lead end, the housing comprising a metal substrate and a composite board having at least one metal plate, the composite plate being formed with a bottom wall and The top open cavity, the substrate is fixed to the composite plate and encloses the top opening, and the battery unit is located in the cavity.

The invention has the beneficial effects that: the housing has two parts: a substrate and a composite board, and the soft composite board can inherit the high anti-explosion safety performance of the flexible packaging battery, and the substrate can be made of a hard material, thereby improving the mechanical strength of the housing, the battery The housing is not easily punctured, which greatly improves the mechanical safety in battery use and manufacture; the manufacturing cost of the substrate relative to the composite board is extremely low, and the production cost of the battery can be reduced. DRAWINGS

1 is a schematic structural view of a battery according to an embodiment of the present invention; Figure 2 is an enlarged view of a portion C in Figure 1;

3 is a schematic view of a first embodiment of the battery processing method of the present invention;

Figure 4 is an enlarged view of A in Figure 3;

Figure 5 is an enlarged view of B in Figure 3;

Figure 6 is a schematic view showing the first embodiment of the battery processing method of the present invention;

Fig. 7 is a schematic view showing the first embodiment of the battery processing method of the present invention. detailed description

A battery, one embodiment of which is a flexible package lithium ion battery, as shown in FIG. 1 and FIG. 2, the battery includes a housing 13 and a battery unit 3 sealed therein with an electrode terminal 4, The electrode lead end 4 may include a positive electrode lead end and a negative electrode lead end, and the negative electrode lead end may be disposed in parallel with the positive electrode lead end; the case 13 includes the substrate 1, a metal layer 11 and a heat fusion layer laminated on the front and back sides of the metal layer 11 a layered structural composite plate 2 composed of layers 12; a hot melt layer 10 is disposed on both the positive electrode lead end and the negative electrode lead end; the layered structural composite plate 2 includes a peripheral edge 6 and a cavity 5 having an opening, and the battery unit 3 is disposed in the cavity In the body 5, the positive electrode lead end and the negative electrode lead end on the battery unit 3 protrude beyond the peripheral edge 6 and are sandwiched between the substrate 1 and the peripheral edge 6. The substrate 1 is integrally connected to the peripheral edge 6 of the laminated structural composite plate. The positive electrode lead terminal and the negative electrode lead terminal are also fusion-bonded and fixed between the substrate 1 and the peripheral edge 6.

The composite panel 2 has a substantially C-shaped cross section including a peripheral wall 21 having an annular cross section and a bottom wall 22 closing the bottom opening 23 of the peripheral wall 21, the peripheral edge 6 being outwardly outward in the radial direction of the casing from the top opening 24 of the peripheral wall 21. Extending, the circumference 6 can be parallel to the bottom wall 22. The substrate 1 encloses the top opening 24 and is connected to the peripheral edge 6 to close the cavity 5. The cross section of the peripheral wall 21 may be a circular ring, a polygonal ring shape or other annular cross section.

The substrate 1 can be made of a hard material that meets the puncture resistance requirements of a flexible packaging battery, such as metal, rigid plastic, and the like.

The composite panel 2 can be made of a soft material that meets the requirements of the flexible packaging battery housing material, such as an existing aluminum-plastic composite film.

In a preferred manner, the substrate 1 is made of aluminum plate, steel plate, aluminum foil or copper foil. The aluminum film or stainless steel is used in a preferred manner. The A3003 or A3005 annealed aluminum alloy sheet is used in a better manner, and the thickness can be set at 0.18~0.35mm. Between 0.22 and 0.3 mm, the substrate 1 of the present embodiment adopts an aluminum alloy sheet of the type A3005 and a thickness of 0.25 mm; the laminated composite panel 2 adopts a layered composite of two layers of PP and an intermediate interlayer of aluminum foil. , a better way to adopt The current aluminum-plastic composite film and other materials for flexible packaging batteries.

As shown in Table 1 and Table 2, Table 1 shows the results of the puncture test of the aluminum-plastic composite film, and Table 2 shows the tensile strength test results of the plastic composite film, which shows that the mechanical strength of the aluminum-plastic composite film is low.

Table 1

The average value is 54.93 54.93. The embodiment adopts an aluminum sheet and an aluminum-plastic composite film, and the joint portion of the aluminum sheet is combined with the aluminum-plastic composite film to improve the mechanical strength of the shell, and at the same time, the safety explosion-proof of the aluminum-plastic composite film is retained. performance. Table 3 shows the tensile strength test results of the aluminum sheets.

table 3

An embodiment of the battery manufacturing method of the present invention, which is a lithium ion battery manufacturing method, includes the following steps:

Example 1

Step 101, as shown in FIG. 3, FIG. 4 and FIG. 5, a battery unit 3 having an electrode terminal 4 such as a positive electrode terminal and a negative electrode terminal is prepared, and an aluminum plate of a type A3003 having a thin plate structure is cut as a certain size. a substrate 1 and an aluminum-plastic film (also referred to as an aluminum-plastic composite film) having a layered structural composite plate having a thin plate structure as a layered structural composite plate 2;

Step 102, as shown in FIG. 6, stamping the layered composite panel 2, so that a cavity 5 and a second cavity 7 having a peripheral edge 6 and accommodating the battery unit 3 are formed;

Step 103, as shown in FIG. 7, the battery unit 3 is placed in the cavity 5 such that the electrode lead end 4 protrudes beyond the peripheral edge 6; the peripheral edge 6 of the layered composite plate 2 is thermally fused to the substrate 1, so that the positive electrode The lead end and the negative lead end are fixed between the substrate 1 and the edge 6 of the composite board 2, and the battery unit 3 is enclosed inside the cavity 5, and at the same time, the joint between the substrate 1 and the layered composite board 2 forms a note. a liquid passage 8 and a second liquid injection passage 9, wherein the liquid injection passage 8 communicates with the cavity 5 and the second cavity 7, and the second liquid injection passage 9 communicates the second cavity 7 with the outside; due to the presence of PP in the aluminum mold Material, PP material melting temperature is about 150 ° C, considering the machine fluctuations, the temperature of the hot melt composite connection is 90 ° C, the composite pressure is 3 MPa;

Step 104: The electrolyte is injected into the cavity 5 through the second liquid injection channel 9, the second cavity 7, and the liquid injection channel 8, and then the second liquid injection channel 9 is closed;

Step 105: charging the battery;

Step 106: Piercing the second cavity 7 to exhaust the exhaust gas generated in the cavity 5 through the liquid injection channel 8 and the second cavity 7;

Step 107: Finally, the liquid injection channel 8 is closed, and the second cavity 7 is cut off to produce a battery as shown in FIG.

In the embodiment, the sealing method of the reserved liquid injection channel has better operability with the method of completely sealing the battery unit at one time, and the production efficiency is greatly improved; the manufacturing method of using the second cavity to discharge the exhaust gas of the cavity can be greatly reduced. The probability of the battery expanding the drum shell; the way of venting the exhaust gas on the second cavity is more conducive to exhaust gas removal.

The battery processed in this embodiment was subjected to a peel strength test of the casing connection, and the test results are shown in Table 4.

Table 4

Example 2: This example is basically the same as Example 1, except that the composite temperature in step 103 is 120 °C.

The processed battery was tested for peel strength by shell connection, and the test results are shown in Table 5.

table 5

Sample No. Maximum force (N) Maximum deformation (mm) Test time (S)

501 52.916 27.6622 33.6

502 47.868 24.8259 30.2

503 63.495 6.4819 8.2

504 54.318 23.7385 28.8 Example 3: This example is basically the same as Example 1, except that the composite temperature in step 103 is 140 °C. The processed battery was tested by the shell connection peel strength, and the test results are shown in Table 6.

Table 6

Embodiment 4: This embodiment is basically the same as Embodiment 1, except that the composite temperature in step 103 is 140 ° C, the composite pressure is IMP, and the processed battery is tested by the shell connection peel strength test. As shown in Table 7.

Table 7

Embodiment 5: This embodiment is basically the same as Embodiment 3. The difference is that the composite temperature in step 103 is 120 ° C, the composite pressure is 5 MPa, and the processed battery passes the shell connection peel strength test, and the test result thereof As shown in Table 8.

Table 8

Comparative Example: The peel strength test results of the conventional composite aluminum-plastic composite film are shown in Table 9.

Table 9

Sample number maximum force (N) maximum deformation (mm) test time (S) 901 36.779 12.8505 15.8

902 37.557 7.5495 9.4

903 34.878 17.3963 21.2 It can be seen from the comparison of the peel strength test that the pressure at 120 °C is higher at a pressure of 3 MPa, and the pressure at 5 MPa is greater at a temperature of 120 ° C, but it is limited to the long-term use of equipment. Using the pressure of 3 MPa, it can be seen from the comparison of the composite strength of the aluminum-plastic composite film that the composite strength of the material used in the present invention can meet the needs of normal production.

Scanning electron microscopy (SEM) test of the composite position of the present invention shows that the composite layer is relatively tight, and the aluminum sheet and the aluminum-plastic composite film penetrate each other, and the composite effect is good.

Another embodiment of the method of manufacturing a battery of the present invention for use in nickel-hydrogen battery processing includes the following steps:

Example 6

Step 601, preparing a battery unit having a positive electrode lead end and a negative electrode lead end, and cutting a certain size of an aluminum plate of the type A3005 having a thin plate structure as the substrate 1 and an aluminum-plastic composite film (also referred to as an aluminum plastic film) having a thin plate structure as Layered composite panel 2;

Step 602, stamping the layered composite panel 2, so that a cavity 5 having a peripheral edge 6 and accommodating the battery unit 3 is formed;

Step 603, the battery unit 3 is placed in the cavity 5, so that the positive electrode lead end and the negative electrode lead end extend beyond the peripheral edge 6;

Step 604, the peripheral edge 6 of the layered composite panel 2 is thermally fused to the substrate 1 such that the positive terminal and the negative terminal are fixed between the substrate 1 and the periphery 6, and the battery unit 3 is sealed inside the cavity 5 to form Complete battery.

In this example, the battery unit 3 has been impregnated with the electrolyte, so that the battery unit can be completely sealed in the chamber 5 at one time.

The above is a detailed description of the present invention in connection with the specific preferred embodiments, and the specific embodiments of the present invention are not limited to the description. It will be apparent to those skilled in the art that the present invention may be made without departing from the spirit and scope of the invention.

Claims

Rights request

A battery comprising a housing and a battery unit sealed in the housing and having an electrode lead end, wherein: the housing comprises a rigid substrate and a soft composite board, and the substrate is connected to the composite board A closed cavity is formed that houses the battery unit, the battery unit being located in the enclosed cavity.

The battery according to claim 1, wherein the composite plate is a laminated structural composite plate having at least one metal layer, and the substrate is a metal plate.

The battery according to claim 2, wherein the substrate and the composite board are joined by heat fusion.

The battery according to claim 2, wherein a hot melt layer is disposed between the substrate and the composite plate, and the substrate and the composite plate are connected by the hot melt layer.

The battery according to claim 4, wherein the material of the hot melt layer is polypropylene or polypropylene.

The battery according to claim 2, wherein the substrate is a metal flat plate, the composite plate has a C-shaped cross section, and the substrate is connected to a peripheral edge of the composite plate to form the closed cavity.

The battery according to claim 2, wherein: the substrate is a metal flat plate, and the composite plate comprises a bottom wall, a peripheral edge, and a peripheral wall having an annular cross section, wherein the bottom wall closes a bottom opening of the peripheral wall, The peripheral edge extends outwardly from the top opening of the peripheral wall in a radial direction of the housing, the substrate enclosing the top opening and being fixed to the periphery.

The battery according to claim 2, wherein the battery lead-out end is taken out from a joint of the substrate and the composite board.

The battery according to any one of claims 2 to 8, wherein the composite plate is an aluminum-plastic composite film.

The battery according to any one of claims 2-8, wherein the substrate is an aluminum plate, a copper plate, a steel plate or a copper foil.

The battery according to any one of claims 1 to 8, wherein the battery is a lithium ion battery.

12. A method of manufacturing a battery, comprising the steps of:

Component preparation step, preparing a battery unit having an electrode lead end, and cutting has a thin plate structure Substrate and composite plate having a layered structure;

Forming a cavity, stamping the composite plate to form a cavity having a circumference and accommodating the battery unit; and installing the battery unit into the cavity such that the electrode lead end of the battery unit protrudes from the periphery Beyond

The battery manufacturing method according to claim 12, wherein the packaging step further comprises forming a liquid injection channel at a junction of the substrate and the layered composite plate, and injecting the electrolyte into the cavity through the liquid injection channel. Body, the step of closing the injection channel.

The method of manufacturing a battery according to claim 12, wherein: the cavity preparation step further comprises a step of forming a second cavity by stamping the layered composite plate; the packaging step further comprising: Forming a liquid injection channel and a second liquid injection channel at a junction with the layered composite plate, wherein the liquid injection channel communicates with the cavity and the second cavity, and the second liquid injection channel communicates with the second cavity and the outside, and passes the electrolyte through the second The injection channel, the second cavity, the injection channel are injected into the cavity, and then the injection channel and the second injection channel are closed.

The battery manufacturing method according to claim 14, wherein the packaging step further comprises: charging the battery, discharging the gas in the cavity to the second cavity through the liquid injection channel, closing the liquid injection channel, And cutting the second cavity.

The battery manufacturing method according to claim 15, wherein in the encapsulating step, a step of piercing the second cavity is further included before the second cavity is cut.

17. A battery comprising a housing and a battery unit having an electrode lead, wherein: the housing comprises a metal substrate and a composite panel having at least one metal layer, the composite panel being formed with a bottom wall and a top opening a cavity, the substrate is thermally fused to the composite plate and encloses the top opening, and the battery unit is located in the cavity.

The battery according to claim 17, wherein the composite sheet is an aluminum-plastic composite film having an aluminum foil layer.

The battery according to claim 17 or 18, wherein: the top opening of the cavity has an outwardly extending periphery, and the substrate is thermally fused to the periphery.