Battery, battery module and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery, a battery module and a battery pack, the battery comprises a packaging film, a pole group, an internal pole lug, an external pole lug and a high-temperature power-off structure, the pole group is arranged in the packaging film; one end of the internal tab is electrically connected with the pole group; the high-temperature power-off structure is arranged between the internal tab and the external tab; and when the battery is short-circuited, the temperature of the internal tab and the external tab rises to a preset value, and the high-temperature power-off structure disconnects the electrical connection between the internal tab and the external tab. According to the battery with the structure, the high-temperature power-off structure is arranged between the internal tab and the external tab, and when the battery is in a normal working state, the internal tab is conducted with the external tab. When the battery is short-circuited, the temperature of the internal tab and the external tab rises, and the high-temperature fusing structure can disconnect the electrical connection between the internal tab and the external tab, so that the connection between the battery and the outside is disconnected, and the safety of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery, a battery module and a battery pack. Background Art

[0002] A soft-pack battery mainly includes a tab, a pole group and a packaging film. The packaging film encapsulates the pole group and the tab and is sealed by hot pressing. The soft-pack battery is packaged with an aluminum-plastic film. In case of potential safety hazards, the soft-pack battery will at most bulge and crack. Therefore, the soft-pack battery has relatively high safety. In the existing soft-pack battery, when the battery is short-circuited, the current passing through the battery tab is too large, resulting in low safety performance of the soft-pack battery. Summary of the Utility Model

[0003] In view of this, the utility model provides a battery, a battery module and a battery pack to solve the problem of low safety of the existing battery in case of short circuit.

[0004] In a first aspect, the utility model provides a battery, comprising:

[0005] A packaging film;

[0006] A pole group disposed inside the packaging film;

[0007] An internal tab, one end of which is electrically connected to the pole group;

[0008] An external tab, one end of which is exposed outside the packaging film and the other end extends into the packaging film and is electrically connected to the other end of the internal tab;

[0009] A high-temperature power-off structure disposed between the internal tab and the external tab; when the battery is short-circuited, the temperatures of the internal tab and the external tab rise to a predetermined value, and the high-temperature power-off structure disconnects the electrical connection between the internal tab and the external tab.

[0010] Advantageous Effects: For the battery with this structure, a high-temperature power-off structure is provided between the internal tab and the external tab. When the battery is in a normal working state, the internal tab conducts the external tab. When the battery is short-circuited, the temperatures of the internal tab and the external tab rise, and the high-temperature fusing structure can disconnect the electrical connection between the internal and external tabs, thereby disconnecting the connection between the battery and the outside world to improve the safety of the battery.

[0011] In an optional embodiment, the high-temperature power-off structure includes a temperature-sensitive conductive polymer layer, and the temperature-sensitive conductive polymer layer connects the internal tab and the external tab; in the normal state of the battery, the temperature-sensitive conductive polymer layer electrically conducts the internal tab and the external tab; in the short-circuit state of the battery, the temperature of the temperature-sensitive conductive polymer layer rises and it becomes non-conductive to disconnect the electrical connection between the internal tab and the external tab.

[0012] Beneficial effects: When the temperature of the tab increases, the temperature of the temperature-sensitive conductive polymer layer increases. The temperature-sensitive conductive polymer layer becomes non-conductive, and the temperature-sensitive conductive polymer layer connects the internal tab and the external tab. Therefore, after the temperature-sensitive conductive polymer layer loses its conductivity, the connection between the internal tab and the external tab can be disconnected. When the temperature of the tab decreases, the conductive free states in the temperature-sensitive conductive polymer begin to fuse, the number of free electrons in the middle of the temperature-sensitive conductive polymer increases, and the circuit is turned on, realizing the electrical connection between the internal tab and the external tab, and the battery can continue to be used after the battery temperature returns to normal.

[0013] In an alternative embodiment, the temperature-sensitive conductive polymer layer comprises an organic polymer PTC.

[0014] In an alternative embodiment, the high-temperature power-off structure comprises a fuse hole provided on the internal tab and / or the external tab.

[0015] Beneficial effects: When the battery is short-circuited, the current passing through the tab increases, and the temperature of the tab rises. The cross-sectional area of the tab at the position where the fuse hole is provided is small, and the current-carrying capacity of the tab on the side of the fuse hole is relatively weak. Therefore, the tab is melted at the position of the fuse hole to disconnect the connection between the internal tab and the external tab, thereby disconnecting the connection between the battery and the outside world, so as to improve the safety of the battery.

[0016] In an alternative embodiment, the fuse hole is provided on the external tab, and the fuse hole is located inside the encapsulation film.

[0017] Beneficial effects: To make the melting position inside the encapsulation film, avoiding large current from being transmitted to the external tab outside the encapsulation film, and effectively preventing the external tab outside the encapsulation film from having too high a temperature and generating safety risks.

[0018] In an alternative embodiment, along the thickness direction of the external tab, the cross-sectional area of the fuse hole is S1, and the cross-sectional area of the external tab is S, where 50% ≤ S1 / S ≤ 80%.

[0019] Beneficial effects: The cross-sectional area of the fuse hole and the cross-sectional area of the solid part of the external tab at the fuse hole are appropriate, which can ensure that the external tab normally passes current under normal conditions, and at the same time, when the battery is short-circuited and the temperature of the external tab rises, the external tab can be melted in time to ensure the safety of the battery.

[0020] In an alternative embodiment, the internal tabs include an internal positive tab and an internal negative tab, and the external tabs include an external positive tab and an external negative tab; the high-temperature power-off structure is disposed between the internal positive tab and the external positive tab, and / or, the high-temperature power-off structure is disposed between the internal negative tab and the external negative tab.

[0021] In an alternative embodiment, tab glue is provided at the connection between the external tab and the encapsulation film.

[0022] Advantageous effects: The tab glue bonds and fixes the external tab to the encapsulation film, ensuring the connection strength and sealing performance at the external tab.

[0023] In a second aspect, the present utility model further provides a battery module, including the battery according to any one of the above. Since the battery module includes the battery, it has the same technical effects as the battery, and will not be elaborated herein.

[0024] In a third aspect, the present utility model further provides a battery pack, including the above battery module. Since the battery pack includes the battery, it has the same technical effects as the battery, and will not be elaborated herein. Description of the Drawings

[0025] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0026] Figure 1 It is a cross-sectional view of a battery according to an embodiment of the present utility model;

[0027] Figure 2 It is Figure 1 a partial enlarged view of part A in

[0028] Figure 3 It is a cross-sectional view of another battery according to an embodiment of the present utility model;

[0029] Figure 4 It is Figure 3 a partial enlarged view of part B in

[0030] Figure 5 It is Figure 4 a schematic view in the A-A direction of

[0031] Figure 6 It is a schematic view of a battery according to an embodiment of the present utility model;

[0032] Figure 7 Schematic diagram of another battery according to an embodiment of the present invention.

[0033] Description of reference numerals in the drawings:

[0034] 1. Encapsulation film; 2. Electrode group; 3. Internal tab; 4. External tab; 5. Temperature-sensing conductive polymer layer; 6. Fusing hole; 7. Tab adhesive; 8. Encapsulation wire. Specific embodiments

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0036] Below in conjunction with Figures 1 to 7 , describe the embodiments of the present invention.

[0037] According to an embodiment of the present invention, on the one hand, a battery is provided, including an encapsulation film 1, an electrode group 2, an internal tab 3, an external tab 4, and a high-temperature power-off structure. The electrode group 2 is disposed inside the encapsulation film 1; one end of the internal tab 3 is electrically connected to the electrode group 2; one end of the external tab 4 is exposed outside the encapsulation film 1, and the other end extends into the encapsulation film 1 and is electrically connected to the other end of the internal tab 3; the high-temperature power-off structure is disposed between the internal tab 3 and the external tab 4; when the battery is short-circuited, the temperatures of the internal tab 3 and the external tab 4 rise to a predetermined value, and the high-temperature power-off structure disconnects the electrical connection between the internal tab 3 and the external tab 4.

[0038] For the battery with this structure, a high-temperature power-off structure is provided between the internal tab 3 and the external tab 4. When the battery is in a normal working state, the internal tab 3 conducts the external tab 4. When the battery is short-circuited, the temperatures of the internal tab 3 and the external tab 4 rise, and the high-temperature fusing structure can disconnect the electrical connection between the internal and external tabs 4, thereby disconnecting the connection between the battery and the outside world to improve the safety of the battery.

[0039] Optionally, in some embodiments, such as Figure 1 and Figure 2As shown, the high-temperature power-off structure includes a temperature-sensitive conductive polymer layer 5, and the temperature-sensitive conductive polymer layer 5 connects the internal tab 3 and the external tab 4; in the normal state of the battery, the temperature-sensitive conductive polymer layer 5 electrically conducts the internal tab 3 and the external tab 4; in the short-circuit state of the battery, the temperature of the temperature-sensitive conductive polymer layer 5 rises and loses conductivity to disconnect the electrical connection between the internal tab 3 and the external tab 4. The temperature-sensitive conductive polymer layer 5 is composed of a temperature-sensitive conductive polymer. When the temperature of the temperature-sensitive conductive polymer rises, the conductive free states in the temperature-sensitive conductive polymer gradually move towards both ends with the increase of temperature, and the free states of electrons in the middle of the polymer decrease, ultimately making the temperature-sensitive conductive polymer non-conductive. Therefore, when the temperature of the tab rises, the temperature of the temperature-sensitive conductive polymer layer 5 rises, and the temperature-sensitive conductive polymer layer 5 becomes non-conductive. Since the temperature-sensitive conductive polymer layer 5 connects the internal tab 3 and the external tab 4, after the temperature-sensitive conductive polymer layer 5 loses conductivity, the connection between the internal tab 3 and the external tab 4 can be disconnected. When the temperature of the tab decreases, the conductive free states in the temperature-sensitive conductive polymer begin to fuse, the free states of electrons in the middle of the temperature-sensitive conductive polymer increase, and the circuit is conducted, realizing the electrical connection between the internal tab 3 and the external tab 4, and the battery can continue to be used after the battery temperature returns to normal.

[0040] Optionally, in some embodiments, as Figure 2 shown, the opposite ends of the internal tab 3 and the external tab 4 are spaced apart, the temperature-sensitive conductive polymer layer 5 connects the internal tab 3 and the external tab 4, and the side of the temperature-sensitive conductive polymer layer 5 facing the external tab 4 overlaps with the external tab 4 by a certain height, and the side of the temperature-sensitive conductive polymer layer 5 facing the internal tab 3 overlaps with the internal tab 3 by a certain height, which can ensure the connection effect of the temperature-sensitive conductive polymer layer 5, and further ensure the conductivity between the internal tab 3 and the external tab 4. The temperature-sensitive conductive polymer layer 5 is in a colloidal structure and is connected between the internal tab 3 and the external tab 4.

[0041] Optionally, in some embodiments, the temperature-sensitive conductive polymer layer 5 includes an organic polymer PTC. The organic polymer PTC is composed of a polymer matrix and conductive particles, and the conductive particles are generally carbon black or metal.

[0042] In other embodiments, as Figures 3 to 5 shown, the high-temperature power-off structure includes a fuse hole 6 provided on the internal tab 3 and / or the external tab 4. When the battery is short-circuited, the current passing through the tab increases, the temperature of the tab rises, the cross-sectional area of the tab at the position where the fuse hole 6 is provided is smaller, and the over-current capacity of the tab on the side of the fuse hole 6 is relatively weak, so that the tab fuses at the position of the fuse hole 6 to disconnect the connection between the internal tab 3 and the external tab 4, thereby disconnecting the connection between the battery and the outside world to improve the safety of the battery.

[0043] Optionally, in some embodiments, as Figure 3 and Figure 4 shown, the fusing hole 6 is provided on the external tab 4, and the fusing hole 6 is located inside the encapsulation film 1, so that the fusing position is inside the encapsulation film 1, preventing large current from being transmitted to the external tab 4 outside the encapsulation film 1, and effectively preventing the temperature of the external tab 4 outside the encapsulation film 1 from being too high and causing safety risks.

[0044] Optionally, in some embodiments, as Figure 5 shown, along the thickness direction of the external tab 4, the cross-sectional area of the fusing hole 6 is S1, and the cross-sectional area of the external tab 4 is S, 50% ≤ S1 / S ≤ 80%. The cross-sectional area of the fusing hole 6 and the cross-sectional area of the solid part of the external tab 4 at the fusing hole 6 are appropriate, which can ensure that the external tab 4 normally passes current under normal conditions, and at the same time, when the battery is short-circuited and the temperature of the external tab 4 rises, the external tab 4 can be timely fused to ensure the safety of the battery.

[0045] As Figure 4 shown, in some embodiments, a strip-shaped fusing hole 6 is provided on the external tab 4, and the strip-shaped fusing hole 6 extends horizontally along the width direction of the tab ( Figure 4 the left-right direction of the external tab 4 in

[0046] Optionally, there are two fusing holes 6, and the two fusing holes 6 are spaced apart in the width direction of the external tab 4.

[0047] In other embodiments, there may be one or more than three fusing holes 6. The fusing hole 6 may also be obliquely arranged.

[0048] As Figure 1 and Figure 3 shown, the internal tab 3 includes an internal positive tab and an internal negative tab, and the external tab 4 includes an external positive tab and an external negative tab; the high-temperature power-off structure is provided between the internal positive tab and the external positive tab, and / or the high-temperature power-off structure is provided between the internal negative tab and the external negative tab, that is, the high-temperature power-off structure can be provided at the positive tab and / or the negative tab. When the temperature of the tab rises due to battery short-circuit, the high-temperature power-off structure can disconnect the connection between the battery positive electrode and the outside of the battery, and / or disconnect the connection between the battery negative electrode and the outside.

[0049] Optionally, in some embodiments, the high-temperature power-off structure is provided between the internal positive tab and the external positive tab. That is, the temperature-sensitive conductive polymer layer 5 connects the internal positive tab and the external positive tab.

[0050] In other embodiments, the fusing hole 6 is provided on the external positive tab.

[0051] As Figures 1 to 4As shown, in some embodiments, a tab adhesive 7 is provided at the connection between the external tab 4 and the encapsulation film 1. The tab adhesive 7 bonds and fixes the external tab 4 to the encapsulation film 1, ensuring the connection strength and sealing performance at the external tab 4.

[0052] Optionally, the tab adhesive 7 is provided at the connection between the external positive tab and the encapsulation film 1, and also at the connection between the external negative tab and the encapsulation film 1.

[0053] As Figure 1 and Figure 3 shown, after the four sides of the encapsulation film 1 are hot-pressed and encapsulated, an encapsulation line 8 is formed, which can effectively ensure the sealing isolation and protection effect on the internal electrode group 2.

[0054] Optionally, in some embodiments, two encapsulation lines 8 are provided at the top of the battery. The two encapsulation lines 8 at the top of the battery are arranged at intervals up and down, which can effectively ensure the top sealing effect of the encapsulation film 1, and at the same time can enhance the fixing effect on the external tab 4 and the internal tab 3, preventing the tabs from shaking when subjected to external forces.

[0055] As Figure 1 and Figure 3 shown, the first encapsulation line 8 at the top partially overlaps with the tab adhesive 7, and the second encapsulation line 8 at the top partially overlaps with the internal tab 3, which can effectively ensure the sealing effect on the internal tab 3 and the external tab 4.

[0056] As Figure 6 shown, in some embodiments, the battery has tabs on the same side, and both the positive tab and the negative tab are located on the same side of the battery.

[0057] As Figure 7 shown, in other embodiments, the battery has tabs on opposite sides, and the positive tab and the negative tab are located on opposite sides of the battery.

[0058] Optionally, the battery includes a soft-pack battery.

[0059] According to an embodiment of the present invention, on the other hand, a battery module is also provided, which includes a plurality of batteries as described in any one of the above.

[0060] In the battery module with this structure, a high-temperature power-off structure is provided between the internal tab 3 and the external tab 4 of the battery inside. When the battery is short-circuited, the temperature of the internal tab 3 and the external tab 4 rises, and the high-temperature fuse structure can disconnect the electrical connection between the internal and external tabs 4, thereby disconnecting the connection between the battery and the outside world to improve the safety of the battery module.

[0061] According to an embodiment of the present invention, on the other hand, a battery pack is also provided, which includes the above-mentioned battery module.

[0062] For the battery pack with this structure, when the battery is short-circuited, the high-temperature fusing structure can disconnect the electrical connection between the inside and the external tab 4, thereby disconnecting the battery from the outside world and improving the safety of the battery pack.

[0063] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A battery, characterized in that: include: Encapsulation film; A pole group, disposed in the packaging film; An internal pole ear, one end of which is electrically connected to the pole group; An external tab, one end of which is exposed from the packaging film, and the other end of which extends into the packaging film and is electrically connected to the other end of the internal tab; A high-temperature power-off structure is provided between the internal pole ear and the external pole ear; when the battery is short-circuited, the temperature of the internal pole ear and the external pole ear rises to a predetermined value, and the high-temperature power-off structure disconnects the electrical connection between the internal pole ear and the external pole ear.

2. The battery according to claim 1, characterized in that The high-temperature power-off structure includes a temperature-sensitive conductive polymer layer, which connects the internal pole ear and the external pole ear. In a normal battery state, the temperature-sensitive conductive polymer layer electrically connects the internal pole ear and the external pole ear. In a short-circuit battery state, the temperature-sensitive conductive polymer layer rises in temperature and does not conduct electricity, thereby disconnecting the electrical connection between the internal pole ear and the external pole ear.

3. The battery according to claim 2, characterized in that The temperature-sensitive conductive polymer layer includes an organic high molecular polymer PTC.

4. The battery according to claim 1, characterized in that The high-temperature power-off structure includes a fuse hole arranged on the inner pole ear and / or the outer pole ear.

5. The battery according to claim 4, characterized in that The fuse hole is provided on the external tab, and the fuse hole is located inside the packaging film.

6. The battery according to claim 5, characterized in that Along the thickness direction of the external pole ear, the cross-sectional area of ​​the fuse hole is S1, the cross-sectional area of ​​the external pole ear is S, and 50%≤S1 / S≤80%.

7. The battery according to any one of claims 1 to 6, characterized in that The internal pole lugs include an internal positive pole lug and an internal negative pole lug, and the external pole lugs include an external positive pole lug and an external negative pole lug; the high-temperature power-off structure is arranged between the internal positive pole lug and the external positive pole lug, and / or the high-temperature power-off structure is arranged between the internal negative pole lug and the external negative pole lug.

8. The battery according to any one of claims 1 to 6, characterized in that A tab glue is provided at the connection between the external tab and the packaging film.

9. A battery module, characterized in that: A battery comprising a plurality of batteries according to any one of claims 1 to 8.

10. A battery pack, characterized in that: Comprising the battery module as claimed in claim 9.

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