First separator plate, second separator plate and internal string battery

Abstract

The utility model discloses a first partition plate, a second partition plate and an internal string battery. A first partition plate comprises a base layer, the base layer comprises a first packaging section and a second packaging section, a first packaging part and a second packaging part are arranged on the two sides, in the thickness direction of the base layer, of the first packaging section respectively, and the melting point of the first packaging part is higher than that of the second packaging part; a third packaging part and a fourth packaging part are arranged on the two sides of the second packaging section in the thickness direction respectively, and the melting point of the fourth packaging part is higher than that of the third packaging part; wherein the first packaging part and the third packaging part are located on the same side face of the base layer, and the second packaging part and the fourth packaging part are located on the other side face of the base layer. According to the first partition plate, the packaging materials with different melting points are respectively arranged on the first packaging section and the second packaging section, and the temperature of the high-temperature pressure head is adjusted, so that hot melting of a single-side packaging layer is realized when the inner string battery is subjected to first battery cell secondary packaging and second battery cell primary packaging.

Description

Technical Field

[0001] The utility model relates to the field of new energy batteries, in particular to a first separator, a second separator and internally connected batteries. Background Art

[0002] With the development of science and technology, lithium-ion battery technology has been continuously improved, and people have higher demands for battery charging speed and energy density. Inner-series batteries are generally composed of two bare cells packed in the same packaging bag, which are completely separated by a partition in the middle. Such a structure can ensure that the cell can be charged at a high rate while improving the energy density of the cell.

[0003] When packaging the inner series battery, the high-temperature sealing head of the packaging machine needs to heat-press the aluminum-plastic film onto the packaging layer of the separator, so that the aluminum-plastic film and the separator are connected to form a closed cavity for accommodating electrolyte and battery cells. When the aluminum-plastic film on one side is hot-pressed, the separator has a certain thermal conductivity, which will raise the temperature of the packaging layer on the other side to the melting point, causing the aluminum-plastic film on the other side to stick, affecting the packaging on the other side. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a first partition that can achieve hot melting of a single-sided packaging layer.

[0005] The utility model also provides a second partition formed by the first partition.

[0006] The utility model also provides an inner series battery having the second separator.

[0007] The utility model also provides an inner series battery having the first separator.

[0008] The first partition according to the embodiment of the utility model comprises:

[0009] A base layer, the base layer comprising a first encapsulation section and a second encapsulation section, the first encapsulation section being provided with a first encapsulation portion and a second encapsulation portion on both sides along a thickness direction of the base layer, the first encapsulation portion having a higher melting point than the second encapsulation portion; the second encapsulation section being provided with a third encapsulation portion and a fourth encapsulation portion on both sides along the thickness direction, the fourth encapsulation portion having a higher melting point than the third encapsulation portion;

[0010] The first encapsulation part and the third encapsulation part are located on the same side of the base layer, and the second encapsulation part and the fourth encapsulation part are located on the other side of the base layer.

[0011] The first partition according to the embodiment of the utility model has at least the following beneficial effects:

[0012] The first partition of the present application arranges packaging materials with different melting points on the first packaging section and the second packaging section respectively, so that the temperature of the high-temperature pressure head can be adjusted to enable the inner-series battery to achieve single-side packaging layer hot melting when the first battery cell is sealed twice and the second battery cell is sealed once, thereby avoiding the phenomenon of double-sided hot melting caused by heat conduction, thereby preventing the second sealing of the first battery cell from affecting the exhaust and drainage of the second battery cell, and also preventing the sealing of the second battery cell from affecting the exhaust and drainage of the first battery cell.

[0013] According to some embodiments of the present invention, the first packaging part and the fourth packaging part are made of the same material, and / or the second packaging part and the third packaging part are made of the same material.

[0014] According to some embodiments of the present invention, the difference between the melting point of the first packaging part and the melting point of the second packaging part is not less than 15°C, and / or the difference between the melting point of the third packaging part and the melting point of the fourth packaging part is not less than 15°C.

[0015] According to some embodiments of the present invention, the first encapsulation part and the third encapsulation part are layered, and the thickness of the first encapsulation part and the third encapsulation part are the same; and / or the second encapsulation part and the fourth encapsulation part are layered, and the thickness of the second encapsulation part and the fourth encapsulation part are the same.

[0016] According to the embodiment of the utility model, the second partition is formed by cutting the first partition described in the embodiment of the first aspect, and the second partition includes a part of the second packaging section.

[0017] The inner series battery according to the embodiment of the utility model comprises the second separator as described in the embodiment of the second aspect.

[0018] The inner series battery according to the embodiment of the utility model comprises

[0019] case;

[0020] The first partition as described in the first aspect of the embodiment, wherein the first partition is disposed through the shell and separates two accommodating chambers in the shell;

[0021] Two battery cells, the two battery cells are respectively arranged in the two accommodating cavities, one of the battery cells is set as the first battery cell, and the other is set as the second battery cell;

[0022] In which, the shell includes a first main body portion covering the first battery cell, a second main body portion covering the second battery cell, a first extension portion connected to the first main body portion and the first partition, and a second extension portion connected to the second main body portion and the first partition. Along the direction away from the battery cell, the first extension portion is sequentially connected to the third packaging portion and the first packaging portion, and the second extension portion is sequentially connected to the fourth packaging portion and the second packaging portion.

[0023] According to some embodiments of the present invention, the first extension portion has a first liquid drainage portion, the second extension portion has a second liquid drainage portion, and the first liquid drainage portion and the second liquid drainage portion are alternately arranged along the thickness direction of the first partition.

[0024] According to some embodiments of the present invention, the first liquid drainage portion is farther away from the battery core than the second liquid drainage portion, and the distance from the second extension portion to the second battery core is not longer than the distance from the first liquid drainage portion to the first battery core;

[0025] Among them, the connection position between the first extension part and the first packaging part is set as the first connection point, and the first connection point is located on the side of the first drainage part away from the first battery cell. The connection position between the second extension part and the second packaging part is set as the second connection point, and the second connection point is located between the first drainage part and the second drainage part.

[0026] According to some embodiments of the utility model, the first extension portion and the third packaging portion have two connection positions, which are respectively set as the third connection position and the fifth connection position, the distance from the third connection position to the first battery cell is greater than the distance from the fifth connection position to the first battery cell, and the connection position between the second extension portion and the fourth packaging portion is set as the fourth connection position, wherein the fourth connection position and the fifth connection position are located on different sides of the same position of the first partition.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described below with reference to the accompanying drawings and embodiments, wherein:

[0029] Figure 1 This is a schematic structural diagram of a first partition according to an embodiment of the first aspect of the utility model;

[0030] Figure 2 This is a schematic structural diagram of an inner series battery according to a fourth embodiment of the utility model;

[0031] Figure 3 This is a schematic diagram of the structure of the inner series battery of the third embodiment of the utility model;

[0032] Figure 4 A schematic flow chart of a packaging method according to a fifth aspect of the present invention;

[0033] Figure 5 This is a schematic diagram of the process of two seals in the fifth embodiment of the utility model.

[0034] Reference numerals:

[0035] first partition 10; base layer 100; first encapsulation section 110; first encapsulation part 111; first connection 1111; second encapsulation part 112; second connection 1121; second encapsulation section 120; third encapsulation part 121; third connection 1211; fourth encapsulation part 122; fourth connection 1221;

[0036] Shell 20; first main body 210; second main body 220; first extension 230; first air bag 231; first drainage portion 232; second extension 240; second air bag 241; second drainage portion 242;

[0037] A first battery cell 31; a second battery cell 32;

[0038] The second partition plate 40 . DETAILED DESCRIPTION

[0039] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0040] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] In the description of the present utility model, "several" means more than one, "many" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used to distinguish the technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0042] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0043] In the description of the utility model, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0044] To facilitate the subsequent understanding of the content of this solution, the packaging process of the battery is briefly described here. First, the battery cell is placed in the receiving cavity formed by the shell, and then the electrolyte is injected into the receiving cavity, and then the first packaging (hereinafter referred to as one sealing) is performed to close the channel for injecting the electrolyte, so that a sealed chamber is formed in the receiving cavity to prevent the entry of external water vapor, air or dust. The battery is then formed to activate the active substances in the battery cell so that the battery can be used normally. After the formation is completed, the air bag needs to be punctured to discharge the exhaust gas generated by the formation, or to discharge the excess electrolyte in the receiving cavity. After the exhaust and drainage are completed, the battery is packaged for the second time (hereinafter referred to as the second sealing) to close the exhaust and drainage channel from the air bag to the receiving cavity, so that the receiving cavity becomes a sealed chamber again. After the packaging is completed, in order to increase the energy density of the battery, a cutting process is also required to remove excess partitions and shell materials.

[0045] Furthermore, in the inner-series battery, since the shell 20 and the partition jointly form two accommodating chambers distributed on both sides of the partition, battery cells are placed in the two accommodating chambers respectively. For the convenience of subsequent description, the two battery cells are named as the first battery cell 31 and the second battery cell 32 respectively. After the first battery cell 31 is filled with liquid, it is necessary to seal it as soon as possible to prevent air from entering the accommodating chamber through the injection channel. Thus, the packaging order of the inner-series battery is the first battery cell 31 injection, the first battery cell 31 sealing, the second battery cell 32 injection, the second battery cell 32 sealing, the first battery cell 31 exhaust and discharge, the first battery cell 31 second sealing, the second battery cell 32 exhaust and discharge, and the second battery cell 32 second sealing. It can be understood that during the exhaust and discharge of the first battery cell 31 and the second battery cell 32, if the battery cells absorb the electrolyte sufficiently, it may also be necessary to do not need to discharge the liquid.

[0046] The embodiment of the first aspect of the present application proposes a first partition 10, such as Figure 1 As shown, the first partition 10 includes a base layer 100. Along the length direction of the base layer 100, that is, from right to left as shown in the figure, the base layer 100 includes a first packaging segment 110 and a second packaging segment 120 arranged in sequence. When the inner battery is sealed, the shell 20 (usually an aluminum-plastic film) is hot-melt connected with the packaging material on the first packaging segment 110 to achieve isolation of the accommodating cavity of the inner battery from the external air, thereby forming the accommodating cavity of the inner battery into a sealed chamber to prevent the entry of external moisture or air.

[0047] The second packaging section 120 is used to connect with the housing 20 during the second sealing to close the exhaust and liquid discharge channels. In some embodiments, the upper and lower sides of the partition are all covered with packaging materials, so that the battery cell can be Figure 2 The position setting shown corresponds to the second packaging segment 120 , or, in other embodiments, the portion of the first partition 10 located in the accommodating cavity is not paved with packaging material, so that the battery cell should be arranged on the side of the second packaging segment 120 away from the first packaging segment 110 .

[0048] When packaging the battery, a high-temperature press head is often used to heat-press the partition. The packaging layers on both sides of the partition in the prior art are made of the same material with the same melting point. Since the base layer 100 of the partition is often made of metal material with good thermal conductivity, when the first battery cell 31 is sealed, the packaging layer on the side of the second battery cell 32 will melt, thereby adhering to the shell 20 on the side of the second battery cell 32, thereby affecting the injection of the second battery cell 32. Alternatively, the high-temperature press head has a first clamping portion and a second clamping portion, which are respectively located on both sides of the first partition 10 during hot pressing, so that both sides of the first partition 10 are hot-pressed at the same time. When the first battery cell 31 is sealed, the packaging layer on the side of the second battery cell 32 will also melt.

[0049] Therefore, in view of the above problems, the present application improves the separator in the prior art into the first separator 10 of the present application, which is used for packaging of internally connected batteries to prevent the heat sealing on one side from affecting the injection or discharge process on the other side. Specifically, Figure 1 As shown, along the two sides of the thickness direction of the base layer 100 (i.e. Figure 1 The first packaging section 110 of the first partition 10 is provided with a first packaging part 111 and a second packaging part 112, respectively, and the melting point of the first packaging part 111 is higher than the melting point of the second packaging part 112. Therefore, when sealing, by controlling the temperature of the high-temperature pressure head, the first packaging part 111 and the second packaging part 112 can be unilaterally hot-melted.

[0050] like Figure 2 As shown, both sides of the second connection 1121 on the first partition 10 have a shell 20. For the convenience of subsequent description, they are named as the first extension portion 230 and the second extension portion 240 respectively. The first extension portion 230 is located on the same side as the first battery cell 31, and the second extension portion 240 is on the same side as the second battery cell 32. The first sealing position of the first battery cell 31 is named as the first connection 1111, and the first extension part 230 of the shell 20 is connected to the first packaging part 111 at the first connection 1111; the first sealing position of the second battery cell 32 is named as the second connection 1121, and the first extension part 230 of the shell 20 is connected to the second packaging part 112 at the second connection 1121; the second sealing position of the first battery cell 31 is named as the third connection 1211, and the second extension part 240 of the shell 20 is connected to the third packaging part 121 at the third connection 1211; the second sealing position of the second battery cell 32 is named as the fourth connection 1221, and the second extension part 240 of the shell 20 is connected to the fourth packaging part 122 at the fourth connection 1221. It should be noted that in the present application, the first battery cell 31 and the second battery cell 32 are on different sides of the same position of the first separator 10.

[0051] If the partition in the prior art is used for packaging, after the second battery cell 32 is sealed, the first extension portion 230 and the second extension portion 240 of the second connection 1121 are both connected to the partition, so that the exhaust and drainage channels of the first battery cell 31 are closed, resulting in the subsequent first battery cell 31 being unable to puncture the airbag to exhaust and drain the air.

[0052] By applying the first partition 10 of the embodiment of the present application, due to the different melting points of the second connection 1121, the melting point of the second packaging part 112 on the side of the second battery cell 32 is lower than the melting point of the first packaging part 111 on the side of the first battery cell 31, so that by adjusting the temperature of the high-temperature pressure head to below the melting point of the first packaging part 111 and above the melting point of the second packaging part 112, the second packaging part 112 can be smoothly hot-melted and connected to the shell 20, thereby sealing the injection channel of the second battery cell 32. At the same time, since the temperature of the high-temperature pressure head is lower than the melting point of the first packaging part 111, even if there is heat conduction when sealing the second battery cell 32, the temperature of the first packaging part 111 rises, but since it cannot reach the melting point of the first packaging part 111, it will not cause the first packaging part 111 at the second connection 1121 to be hot-melted.

[0053] In addition, if Figure 1 As shown, along the two sides of the thickness direction of the base layer 100, the second encapsulation section 120 of the first partition 10 is provided with a third encapsulation part 121 and a fourth encapsulation part 122 respectively, wherein the melting point of the fourth encapsulation part 122 is higher than the melting point of the third encapsulation part 121. It should be noted that the first encapsulation part 111 and the third encapsulation part 121 are located on the same side of the base layer 100, and the second encapsulation part 112 and the fourth encapsulation part 122 are located on the other side of the base layer 100.

[0054] By different arrangement of the packaging materials on both sides of the second packaging section 120, it is possible to avoid affecting the exhaust and liquid discharge of the second battery cell 32 when the first battery cell 31 is sealed. Figure 2 As shown, when the first battery cell 31 is sealed, Figure 2 The third connection 1211 is shown to be hot-melted. If the prior art partition is used for packaging, the shell 20 on both sides of the third connection 1211 will form a connection relationship with the partition, so that after the first battery cell 31 is sealed, the exhaust and liquid discharge channel of the second battery cell 32 is closed, resulting in the subsequent second battery cell 32 being unable to puncture the air bag to exhaust and discharge liquid.

[0055] By applying the first partition 10 of the embodiment of the present application, due to the different melting points of the third connection 1211, the melting point of the third packaging part 121 on the first battery cell 31 side is lower than the melting point of the fourth packaging part 122 on the second battery cell 32 side. Therefore, by adjusting the temperature of the high-temperature pressure head to below the melting point of the fourth packaging part 122 and above the melting point of the third packaging part 121, single-sided hot melting of the third packaging part 121 can be achieved, thereby avoiding affecting the exhaust and liquid discharge of the second battery cell 32.

[0056] Based on the above, the first partition 10 of the present application sets packaging materials with different melting points on the first packaging section 110 and the second packaging section 120 respectively, so that the temperature of the high-temperature pressure head can be adjusted to enable the inner series battery to achieve single-side packaging layer hot melting when the first battery cell 31 and the second battery cell 32 are sealed, thereby avoiding the double-sided hot melting caused by heat conduction, thereby avoiding the second sealing of the first battery cell 31 from affecting the exhaust and drainage of the second battery cell 32, and also avoiding the second sealing of the second battery cell 32 from affecting the exhaust and drainage of the first battery cell 31, thereby improving production efficiency.

[0057] In some embodiments, the first encapsulation part 111 and the fourth encapsulation part 122 are made of the same material, so that the melting points of the first encapsulation part 111 and the fourth encapsulation part 122 are consistent. In other embodiments, the second encapsulation part 112 and the third encapsulation part 121 are made of the same material, so that the melting points of the second encapsulation part 112 and the third encapsulation part 121 are consistent. It can be understood that when the materials of the first encapsulation part 111 and the fourth encapsulation part 122 are the same, the materials of the second encapsulation part 112 and the third encapsulation part 121 can be the same or different. Similarly, when the materials of the second encapsulation part 112 and the third encapsulation part 121 are the same, the materials of the first encapsulation part 111 and the fourth encapsulation part 122 can be the same or different.

[0058] In some embodiments, the difference between the melting point of the first encapsulation part 111 and the melting point of the second encapsulation part 112 is not less than 15° C. In other embodiments, the difference between the melting point of the third encapsulation part 121 and the melting point of the fourth encapsulation part 122 is not less than 15° C. Taking the melting point of the first encapsulation part 111 as 140° C. and the melting point of the second encapsulation part 112 as 125° C. as an example, the difference between the melting points of the first encapsulation part 111 and the second encapsulation part 112 is more than 15° C., which is conducive to increasing the temperature of the high-temperature pressure head as much as possible, thereby prompting the low-melting-point encapsulation layer to melt quickly.

[0059] In some embodiments, the first encapsulation part 111 and the third encapsulation part 121 are in a layered form, and the first encapsulation part 111 and the third encapsulation part 121 have the same thickness. In other embodiments, the second encapsulation part 112 and the fourth encapsulation part 122 are in a layered form, and the second encapsulation part 112 and the fourth encapsulation part 122 have the same thickness.

[0060] The embodiment of the second aspect of the present application further proposes a second separator 40, which is made of the first separator 10. Specifically, it should be understood that the first separator 10 is used in the packaging process of the inner series battery, but after the packaging is completed, in order to shorten the inner series battery along its length direction (such as Figure 2 The size in the left and right direction shown in FIG. 1 ) needs to be completely cut off the portion of the fourth connection 1221 of the first separator 10 away from the battery cell, that is, Figure 2It can be understood that since the fourth connection 1221 is located on the second packaging segment 120, the cut portion includes the first packaging segment 110 and part of the second packaging segment 120, so that Figure 3 As shown, the second partition plate 40 includes a portion of the second encapsulation section 120 .

[0061] It should be noted that, in the second partition 40 of the second aspect, its length Y has the following relationship with the width X of the battery and the thickness d of the battery: X+2.4≤Y≤X+4d; if Y<X+2.4, the battery will have poor packaging and aluminum leakage at the folded edge; if Y>X+4d, the battery will have folded edge exceeding the main body and cause poor size.

[0062] The third aspect of the present application provides an internal series battery, such as Figure 3 As shown, the inner-series battery includes the second partition plate 40 proposed in the second embodiment. It can be understood that the inner-series battery is a finished battery after the packaging and cutting processes are completed.

[0063] It should be noted that in the existing internal series batteries, the addition of the middle partition will cause the heat dissipation of the battery to deteriorate. In addition, since the melting point of the glue layer coated on the partition in the prior art is relatively high, if heat accumulates inside the battery, it is not easy to break open the middle, and the hot box performance is poor.

[0064] In the embodiment of the third aspect of the present application, since the melting point of the third packaging part 121 is lower than that of the fourth packaging part 122, during the heat accumulation process of the hot box test, the third connection 1211 is more susceptible to the temperature rise than the fourth connection 1221, and is thus opened in advance by the gas pressure inside the battery. That is, the inner series battery in the embodiment of the third aspect of the present application is provided with a weak point, so that it can be opened in advance when heat accumulation occurs inside the battery, thereby improving the hot box performance.

[0065] In order to verify the superiority of the hot box performance of the battery in series in the present application, a control experiment as shown in the following table was carried out.

[0066]

[0067] It should be noted that the above table shows the results of hot box tests of three groups of inner series batteries at 130°C, 132°C and 134°C, respectively, wherein the melting point of the third packaging part of the comparative example is 165°C, and the melting point of the fourth packaging part is also 165°C. The melting point of the third packaging part 121 of the embodiment of the present application is 130°C, and the melting point of the fourth packaging part 122 is 165°C. In the hot box tests at 130°C and 132°C, the three groups of batteries in the comparative example and the embodiment passed the test. In the hot box test at 134°C, the three groups of batteries in the comparative example failed the test, and the three groups of batteries in the embodiment of the present application passed the test. It can be clearly seen that compared with the inner series batteries applied to ordinary partitions, the hot box performance of the inner series batteries of the present application is improved by 1°C to 2°C.

[0068] The fourth aspect of the present application provides an inner-series battery, which is the inner-series battery of the third aspect of the present application before the cutting process. Figure 2 As shown, the inner series battery includes a housing 20, two battery cells (i.e., the first battery cell 31 and the second battery cell 32 mentioned above) and the first separator 10 mentioned in the first embodiment, as shown in FIG. Figure 2 As shown, the first partition 10 is disposed through the housing 20 and separates two accommodating chambers in the housing 20. The first battery cell 31 and the second battery cell 32 are respectively disposed in the two accommodating chambers.

[0069] The housing 20 includes a first main body 210 covering the first battery cell 31, and the first main body 210 and the first partition 10 jointly define a first accommodation cavity for accommodating the first battery cell 31. The housing 20 also includes a second main body 220 covering the second battery cell 32, and the second main body 220 and the first partition 10 jointly define a second accommodation cavity for accommodating the second battery cell 32. The housing 20 also includes a first extension portion 230 connected to the first main body 210 and a second extension portion 240 connected to the second main body 220. The first extension portion 230 and the second extension portion 240 are respectively located on both sides of the first partition 10 and are used to connect to both sides of the first partition 10 so that the first accommodation cavity and the second accommodation cavity form a closed chamber.

[0070] It can be understood that after the first battery cell 31 and the second battery cell 32 are sealed once and twice, there are four connections on the first partition 10, wherein, along the direction away from the first battery cell 31, the first extension portion 230 is connected to the third packaging portion 121 and the first packaging portion 111 in sequence. In combination with the foregoing, the first extension portion 230 is connected to the third packaging portion 121 to form a third connection 1211, and the first extension portion 230 is connected to the first packaging portion 111 to form a first connection 1111. Along the direction away from the second battery cell 32, the second extension portion 240 is connected to the fourth packaging portion 122 and the second packaging portion 112 in sequence. In combination with the foregoing, the second extension portion 240 is connected to the fourth packaging portion 122 to form a fourth connection 1221, and the second extension portion 240 is connected to the second packaging portion 112 to form a second connection 1121.

[0071] Based on the above structure, it can be found that the internal series battery of this structure realizes the sealing operation of the first battery cell 31 and the second battery cell 32 through the first partition 10 of the first aspect embodiment, and because the first partition 10 of the first aspect embodiment is adopted, the mutual interference between the various steps is avoided.

[0072] In some embodiments, the first extension portion 230 has a first drainage portion 232, and the second extension portion 240 has a second drainage portion 242. It should be explained that the first drainage portion 232 and the second drainage portion 242 are formed by puncturing the air bag. Figure 2 As shown, air bags are provided on the first extension part 230 and the second extension part 240, which are respectively named as the first air bag 231 and the second air bag 241 for the convenience of subsequent description. The first air bag 231 is used for exhaust and liquid discharge after being punctured, and then the first liquid discharge part 232 is formed, and the second air bag 241 is used for exhaust and liquid discharge after being punctured, and then the second liquid discharge part 242 is formed.

[0073] It should be noted that, in the airbag puncture process of the related art, taking the puncture of the first airbag 231 as an example, the puncture needle will puncture the first airbag 231 and penetrate the first partition 10, so that the second extension portion 240 on the other side of the first partition 10 is also punctured. Therefore, in the present application, in order to avoid the first airbag 231 and the second airbag 241 being punctured at the same time, the first airbag 231 and the second airbag 241 are staggered along the thickness direction of the first partition 10, that is, Figure 2 As shown, along the projection in the thickness direction of the first partition 10 (i.e., the up-down direction in the figure), there is no overlapping area between the first airbag 231 and the second airbag 241. Therefore, when the first airbag 231 is punctured, the second airbag 241 will not be affected. Furthermore, the first liquid drainage portion 232 and the second liquid drainage portion 242 formed after the first airbag 231 and the second airbag 241 are punctured are also staggered.

[0074] In some embodiments, the first drainage portion 232 is farther away from the battery cell than the second drainage portion 242. Figure 2 As shown, the first drainage portion 232 is located on the right side of the second drainage portion 242, and the battery cell, the first drainage portion 232 and the second drainage portion 242 are arranged in sequence. In addition, the distance from the second extension portion 240 to the second battery cell 32 is not longer than the distance from the first drainage portion 232 to the first battery cell 31, and the first connection 1111 is located on the side of the first drainage portion 232 away from the first battery cell 31, that is, on the right side of the first drainage portion 232, so that the second extension portion 240 is not arranged on the other side of the first partition 10 corresponding to the position of the first connection 1111 and the first air bag 231. The second connection 1121 is located between the first drainage portion 232 and the second drainage portion 242.

[0075] Based on the above structure, when the first battery cell 31 is sealed, the temperature of the high-temperature pressure head can be set to be higher than the melting point of the first packaging part 111. Since there is no second extension part 240 at the first connection 1111, there is no need to worry that the hot melting of the first connection 1111 will affect the injection of the second battery cell 32. After the second battery cell 32 is injected, the second connection 1121 is hot-melted, and the temperature of the high-temperature pressure head is set to be lower than the melting point of the first packaging part 111, thereby achieving a single-sided hot melt on the side of the second battery cell 32, which will not affect the exhaust and liquid discharge of the first battery cell 31. When puncturing the first air bag 231, since the first air bag 231 and the second air bag 241 are staggered, and the second extension part 240 does not extend to the position of the first air bag 231, when the first partition 10 is pierced at the position of the first air bag 231, it will not cause leakage of gas or liquid in the second battery cell 32. When puncturing the second air bag 241 , since the first battery cell 31 has been sealed at the third connection 1211 , the third connection 1211 is closer to the battery cell than the second air bag 241 , so puncturing the second partition 40 at the position of the second air bag 241 will not cause air or liquid leakage in the first battery cell 31 .

[0076] Furthermore, the distance from the third connection 1211 to the first battery cell 31 is greater than the distance from the fourth connection 1221 to the first battery cell 31. Thus, the second sealing position of the first battery cell 31 is farther away from the battery cell than the second sealing position of the second battery cell 32. It should be noted that since the melting point of the fourth packaging part 122 is higher than the melting point of the third packaging part 121, when the fourth packaging part 122 is hot-melted, the high-temperature pressure head will heat-melt both the third packaging part 121 and the fourth packaging part 122, and the first extension part 230 and the third packaging part 121 have two connection points, the first connection point is the third connection 1211 generated by the second sealing of the first battery cell 31, and the second connection point is the fifth connection generated by the second sealing of the second battery cell 32. It can be understood that the fifth connection and the fourth connection 1221 are located at the same position of the first partition 10 along the length direction, but are on different sides of the first partition 10 along the thickness direction.

[0077] Since the first extension portion 230 and the second extension portion 240 are both connected to the first partition 10 when the second battery cell 32 is sealed, the first accommodating cavity and the second accommodating cavity both form a sealed chamber. Therefore, in the subsequent cutting process, the partition and the shell 20 on the side of the fourth connection 1221 away from the battery cell can be completely cut off to shorten the length direction of the battery.

[0078] The fifth aspect of the present application proposes a packaging method, which is applied to an inner series battery. It should be noted that the packaging method ultimately forms the inner series battery in the fourth aspect of the present application. Therefore, for some packaging steps, reference can be made to the description in the fourth aspect of the present application. Figure 4 As shown, the packaging method includes the following specific steps:

[0079] S100 , preparing the housing 20 , the first battery cell 31 , the second battery cell 32 and the first separator 10 .

[0080] The housing 20 includes a first main body 210, a second main body 220, a first extension 230 and a second extension 240. The first main body 210 and the first partition 10 define a first accommodating cavity, the second main body 220 and the first partition 10 define a second accommodating cavity, the first extension 230 is connected to the first main body 210 and is used to be connected to the first partition 10, and the second extension 240 is connected to the second main body 220 and is used to be connected to the first partition 10. The first main body 210 and the second main body 220 are respectively located on different sides of the first partition 10, and the first extension 230 and the second extension 240 are respectively located on different sides of the partition. A first air bag 231 is provided on the first extension 230, and a second air bag 241 is provided on the second extension 240. The length of the first extension 230 is greater than the length of the second extension 240.

[0081] The first partition 10 includes a base layer 100, and the base layer 100 includes a first encapsulation section 110 and a second encapsulation section 120. The first encapsulation tube is provided with a first encapsulation part 111 and a second encapsulation part 112 on both sides of the base layer 100 in the thickness direction, respectively. The melting point of the first encapsulation part 111 is higher than that of the second encapsulation part 112. The second encapsulation section 120 is provided with a third encapsulation part 121 and a fourth encapsulation part 122 on both sides of the thickness direction, respectively. The melting point of the fourth encapsulation part 122 is higher than that of the third encapsulation part 121. The first encapsulation part 111 and the third encapsulation part 121 are located on the same side of the base layer 100, and the second encapsulation part 112 and the fourth encapsulation part 122 are located on the other side of the base layer 100.

[0082] S200, placing the first battery cell 31 and the second battery cell 32 into the first accommodating cavity and the second accommodating cavity respectively;

[0083] S300, injecting electrolyte into the first accommodating cavity from the injection gap between the first extension portion 230 and the first separator 10;

[0084] It can be understood that at this time, there is no connection between the first extension portion 230 and the first separator 10 , so that a gap for liquid injection is defined between the first extension portion 230 and the first separator 10 .

[0085] S400, hot-melting the first packaging portion 111 at a first temperature at the first connection point 1111 to connect the first packaging portion 111 and the first extension portion 230;

[0086] After the first packaging part 111 is connected to the first extension part 230, the injection gap of the first accommodating cavity is closed, so that the first accommodating cavity forms a closed chamber. The first connection 1111 is located on the side of the first air bag 231 away from the first main body 210, and the distance between the first connection 1111 and the first main body 210 is greater than the length of the second extension part 240, and the first temperature is higher than the melting point of the first packaging part 111. Therefore, the high temperature heat melting of the first connection 1111 will not affect the second extension part 240, and thus will not affect the sealing of the second battery cell 32.

[0087] S500, injecting electrolyte into the second accommodating cavity from the injection gap between the second extension portion 240 and the first separator 10;

[0088] Similarly, at this time, there is no connection between the second extension portion 240 and the first separator 10 , so that a gap for liquid injection is defined between the second extension portion 240 and the first separator 10 .

[0089] S600, hot-melting the second packaging portion 112 at a second temperature at the second connection point 1121 to connect the second packaging portion 112 and the second extension portion 240;

[0090] After the second packaging part 112 is connected to the second extension part 240, the injection gap of the second accommodating cavity is closed, so that the second accommodating cavity forms a closed chamber. The second connection 1121 is located between the second air bag 241 and the first air bag 231, and the second temperature is lower than the melting point of the first packaging part 111 and higher than the melting point of the second packaging part 112. Therefore, after the temperature of the high-temperature pressing head is adjusted to the second temperature, only the second packaging part 112 will be melted, and the first packaging part 111 will not be melted.

[0091] Based on the above, through the internal series battery of this structure, in combination with the packaging method of the fifth aspect of the present application, it is possible to achieve step-by-step packaging of the battery cells of the internal series battery, and the packaging of each battery cell will not affect each other.

[0092] Further, such as Figure 5As shown, the second sealing steps for each battery cell are as follows:

[0093] S700, forming the first battery cell 31;

[0094] S710, puncturing the first air bag 231 to discharge waste gas and / or excess electrolyte in the first accommodating cavity;

[0095] After the first air bag 231 is punctured, the first liquid drainage portion 232 on the inner-series battery of the fourth embodiment is formed, which is used to discharge the waste gas generated after the formation in the first accommodating cavity. Since the liquid absorption capacity of each battery cell is different, there may be excess electrolyte in the accommodating cavity, which can also be discharged through the first liquid drainage portion 232.

[0096] S720, hot-melt the third packaging portion 121 at the third connection portion 1211 at a third temperature to cut off the communication channel between the first air bag 231 and the first accommodating cavity;

[0097] The third temperature is lower than the melting point of the fourth packaging part 122 and higher than the melting point of the third packaging part 121. Therefore, the third connection part 1211 is single-sided hot-melting, and does not affect the packaging layer on the side of the second battery cell 32.

[0098] S800, the second battery cell 32 is formed;

[0099] S810, puncturing the second air bag 241 to discharge waste gas and / or excess electrolyte in the second accommodating chamber;

[0100] S820, hot-melt the fourth packaging part 122 and the fourth packaging part 122 at the fourth connection point 1221 at a fourth temperature, so that the first extension part 230 and the second extension part 240 are respectively connected to the first partition 10;

[0101] The fourth temperature is higher than the melting point of the fourth packaging portion 122 , so that both sides of the first partition 10 at the fourth connection 1221 are thermally melted to achieve connection between the first partition 10 and the first extension portion 230 and the second extension portion 240 , respectively.

[0102] In addition, due to the different liquid absorption capabilities of each battery cell, the injected electrolyte may be discharged from the drainage part after formation, resulting in unequal electrolyte retention in each accommodating cavity. If the retention amounts of each battery cell are different, it may cause inconsistencies in the service life and electrical parameters of the battery cell, thus affecting the normal use of the battery. In some embodiments, during the packaging process of the inner-series battery, the weight of the inner-series battery at different stages is obtained by step-by-step weighing, so as to calculate the retention amount of electrolyte in each accommodating cavity, and then the electrical parameters of each battery cell are regulated by the circuit board, providing a reference basis for balancing the voltage and current values ​​of the subsequent battery cells, so as to maximize the number of charge and discharge times of each battery cell.

[0103] Specifically, after step S600, the inner series of batteries are weighed to obtain a first weight M1, after step S720, the inner series of batteries are weighed to obtain a second weight M2, and after step S820, the inner series of batteries are weighed to obtain a third weight M3. The packaging method further includes the following steps:

[0104] S900 , obtaining the liquid retention amount of the first battery cell 31 and the liquid retention amount of the second battery cell 32 according to the first weight M1 , the second weight M2 , and the third weight M3 .

[0105] Furthermore, in step S300, the liquid injection weight H1 of the first battery cell 31 is obtained, and in step S500, the liquid injection weight H2 of the second battery cell 32 is obtained, so that the liquid retention amount A1 of the first battery cell 31 is A1 = H1-(M2-M1), and the liquid retention amount A2 of the second battery cell 32 is A2 = H2-(M3-M2).

[0106] It should be explained that the injection weight can be calculated by the weight difference before and after the injection, or by weighing the electrolyte before the electrolyte is injected, or it can be calculated by the volume of the injected electrolyte, etc.

[0107] The embodiments of the utility model are described in detail above in conjunction with the accompanying drawings, but the utility model is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the utility model. In addition, the embodiments of the utility model and the features in the embodiments can be combined with each other without conflict.

Claims

1. The first partition, characterized in that: include: A base layer, the base layer comprising a first encapsulation section and a second encapsulation section, the first encapsulation section being provided with a first encapsulation portion and a second encapsulation portion on both sides along a thickness direction of the base layer, the first encapsulation portion having a higher melting point than the second encapsulation portion; the second encapsulation section being provided with a third encapsulation portion and a fourth encapsulation portion on both sides along the thickness direction, the fourth encapsulation portion having a higher melting point than the third encapsulation portion; The first encapsulation part and the third encapsulation part are located on the same side of the base layer, and the second encapsulation part and the fourth encapsulation part are located on the other side of the base layer.

2. The first separator according to claim 1, characterized in that: The first encapsulation part and the fourth encapsulation part are made of the same material, and / or the second encapsulation part and the third encapsulation part are made of the same material.

3. The first separator according to claim 1, characterized in that: The difference between the melting point of the first packaging part and the melting point of the second packaging part is not less than 15°C, and / or the difference between the melting point of the third packaging part and the melting point of the fourth packaging part is not less than 15°C.

4. The first separator according to claim 1, characterized in that: The first encapsulation part and the third encapsulation part are layered, and the first encapsulation part and the third encapsulation part have the same thickness; and / or the second encapsulation part and the fourth encapsulation part are layered, and the second encapsulation part and the fourth encapsulation part have the same thickness.

5. The second partition, characterized in that: The second partition is formed by cutting the first partition described in any one of claims 1 to 4, and includes a portion of the second packaging segment.

6. Internal series battery, characterized in that, include: The second separator as claimed in claim 5.

7. Internal series battery, characterized in that, include: case; The first partition according to any one of claims 1 to 4, wherein the first partition is disposed through the shell and separates two accommodating chambers in the shell; Two battery cells, the two battery cells are respectively arranged in the two accommodating cavities, one of the battery cells is set as the first battery cell, and the other is set as the second battery cell; In which, the shell includes a first main body portion covering the first battery cell, a second main body portion covering the second battery cell, a first extension portion connected to the first main body portion and the first partition, and a second extension portion connected to the second main body portion and the first partition. Along the direction away from the battery cell, the first extension portion is sequentially connected to the third packaging portion and the first packaging portion, and the second extension portion is sequentially connected to the fourth packaging portion and the second packaging portion.

8. The inner series battery according to claim 7, characterized in that: The first extension portion has a first liquid drainage portion, the second extension portion has a second liquid drainage portion, and the first liquid drainage portion and the second liquid drainage portion are alternately arranged along the thickness direction of the first partition plate.

9. The inner series battery according to claim 8, characterized in that: The first liquid drainage portion is farther away from the battery core than the second liquid drainage portion, and the distance from the second extension portion to the second battery core is not longer than the distance from the first liquid drainage portion to the first battery core; Among them, the connection position between the first extension part and the first packaging part is set as the first connection point, and the first connection point is located on the side of the first drainage part away from the first battery cell. The connection position between the second extension part and the second packaging part is set as the second connection point, and the second connection point is located between the first drainage part and the second drainage part.

10. The inner series battery according to claim 7, characterized in that: The first extension portion and the third packaging portion have two connection positions, which are respectively set as the third connection position and the fifth connection position. The distance from the third connection position to the first battery cell is greater than the distance from the fifth connection position to the first battery cell. The connection position between the second extension portion and the fourth packaging portion is set as the fourth connection position, wherein the fourth connection position and the fifth connection position are located on different sides of the same position of the first partition.

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