Battery module

Abstract

The invention discloses a battery module capable of inhibiting arc discharge. The battery module comprises a first conductive part, a second conductive part, a plurality of battery cells and a gas release part, and the plurality of battery cells are electrically connected. And the gas release part is arranged on the plurality of battery cells, the gas release part has a release temperature, and the gas release part can release non-combustible gas to the plurality of battery cells in a state that the temperature of the plurality of battery cells is higher than the release temperature.

Description

Technical Field

[0001] The present application relates to a battery module, and in particular to a battery module equipped with a gas release portion, wherein the gas release portion can release non-flammable gas to suppress arc discharge effects of the battery cell group. Background Art

[0002] As lithium battery modules are increasingly used, the demand for fire safety is also increasing. When a large-scale battery module catches fire, it is often accompanied by the emission of a large amount of high-temperature combustible gas. These combustible gases will undergo pyrolysis reactions in a high-temperature environment and produce ionization.

[0003] Before the battery cells of the battery module explode, there is a significant voltage difference between the electrical connection parts and the battery module shell or the surrounding atmosphere. In an ionized environment, this voltage difference will form an electrical conduction path, allowing electrons to discharge to the shell or the atmosphere, causing the shell to melt and form holes, or generating arcs in the atmosphere, thereby triggering the combustion of combustible gases and exacerbating the spread of fire.

[0004] In recent years, the green industry has placed increasing demands on the safety of battery modules, and the number of batteries carried in battery modules has also continued to increase. However, the battery modules and materials currently used can no longer meet the requirements of the ever-evolving fire protection and fire prevention regulations. Therefore, how to further prevent arcing in battery modules is an issue that urgently needs to be addressed. Summary of the invention

[0005] In view of the problems mentioned in the background art, the purpose of the present application is to provide a battery module that dilutes the ionization generated in the battery module before the thermal explosion occurs, so as to slow down the arc discharge and terminate it.

[0006] According to the above purpose, the present application provides a battery module, comprising a plurality of battery cell groups and at least one gas release part. The plurality of battery cell groups are electrically connected. The gas release part is arranged at one end of the battery cell group, and the gas release part has a release temperature. When the temperature of the plurality of battery cells is greater than the release temperature, the gas release part releases non-flammable gas to the plurality of battery cells, so as to suppress the arc discharge effect of the battery cell group.

[0007] Wherein, the at least one gas release portion comprises a first gas release portion and a second gas release portion, which are respectively arranged at two ends of the battery cell group.

[0008] Wherein, the plurality of battery cells are arranged in a shell, and the gas release portion is also arranged around the inner wall of the shell.

[0009] The release temperature is greater than the operating temperature of the multiple battery cells and less than the temperature at which thermal runaway occurs in the multiple battery cells.

[0010] Wherein, the gas release part is a carbonic acid raw material.

[0011] Wherein, the carbonic acid raw material is sodium bicarbonate, and the sodium bicarbonate begins to gradually decompose above the release temperature to generate sodium carbonate, the non-combustible gas and water, and the non-combustible gas is carbon dioxide.

[0012] Wherein, the release temperature is 127°C.

[0013] To summarize, before thermal runaway occurs or the operating temperature of the battery module becomes abnormal to the point where thermal runaway occurs, the battery module of the present application releases non-flammable gas through the gas release portion to dilute the ionization generated in the battery module, thereby slowing down the arc discharge and terminating it. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the first embodiment of the present application.

[0015] Figure 2 It is a schematic diagram of the second embodiment of the present application.

[0016] Figure 3 It is a schematic diagram of the third embodiment of the present application.

[0017] Figure 4 This is a schematic diagram of the fourth embodiment of the present application.

[0018] Figure 5 It is a schematic diagram of the fifth embodiment of the present application.

[0019] Explanation of the reference numerals: 1 - battery module; 2 - first conductive part; 3 - second conductive part; 4 - battery cell; 5 - gas release part; 6 - circuit board; 7 - casing. DETAILED DESCRIPTION

[0020] The embodiments of the present application will be further explained below in conjunction with the relevant drawings. As much as possible, the same reference numerals represent the same or similar components in the drawings and the specification. In the drawings, the shapes and thicknesses may be exaggerated for simplicity and convenience. It is understood that the components not specifically shown in the drawings or described in the specification are known to those of ordinary skill in the art. Those of ordinary skill in the art may make various changes and modifications based on the contents of the present application.

[0021] like Figure 1-Figure 3As shown, the present application provides a battery module, the battery module 1 includes a plurality of battery cell groups 4 and at least one gas release portion 5. The plurality of battery cell groups 4 respectively have a plurality of battery cells 40, and the plurality of battery cells 40 are electrically connected. The gas release portion 5 is arranged at at least one end of the battery cell group, and the gas release portion 5 has a release temperature. When the temperature of any one of the plurality of battery cells 40 is greater than the release temperature, the gas release portion 5 will release non-flammable gas to the plurality of battery cells 40, which is used to dilute the ionization generated in the battery module 1, so as to slow down the arc discharge and terminate it.

[0022] Furthermore, the plurality of battery cells 40 are disposed between the first conductive part 2 and the second conductive part 3 so that the plurality of battery cells 40 are electrically connected, and the gas release part 5 is disposed on one or both of the first conductive part 2 or the second conductive part 3 .

[0023] In some embodiments of the present application, the plurality of battery cells 40 are electrically connected in parallel via the first conductive portion 2 and the second conductive portion 3 (eg Figure 1 As shown), or the plurality of cells 40 are electrically connected in series via the first conductive portion 2 and the second conductive portion 3 (as shown Figure 2 As shown), or the plurality of cells 40 are connected in series and in parallel through the first conductive part 2 and the second conductive part 3 (as shown Figure 3 As shown), the series connection combined with the parallel connection does not limit Figure 3 The multiple battery cells 40 shown are connected in parallel and then connected in series, or multiple battery cells 40 can be connected in series and then connected in series. Of course, the multiple battery cells 40 can also form a required series-parallel circuit through the first conductive part 2 and the second conductive part 3 as required. The first conductive part 2 and the second conductive part 3 are nickel sheets, copper-aluminum composite busbars, copper busbars, total positive and total negative busbars, aluminum busbars, or copper soft connections, aluminum soft connections, copper foil soft connections, etc.

[0024] In some embodiments of the present application, Figure 4 As shown, Figure 4 is a side view of the battery module. Figure 4Only one battery cell 40 is drawn in the figure, and a circuit board 6 is arranged between the multiple battery cells 40 and the gas release part 5, one end of the first conductive part 2 is connected to the circuit board 6, and the other end of the first conductive part 2 is connected to the other end of the second conductive part, so that the circuit board 6 is electrically connected to the multiple battery cells 40 via one end of the first conductive part 2 and one end of the second conductive part. The circuit board 6 includes a battery management system, which is a system for managing the battery module 1, and has the function of measuring the voltage, current, and temperature of the battery module 1, preventing or avoiding abnormal conditions such as over-discharge, over-charge, and over-temperature of the battery module 1, and performing intelligent charge and discharge management on the battery module 1 according to these abnormal conditions, so that the battery module 1 can operate normally and extend its service life.

[0025] In order to more quickly dilute the ionization generated in the battery module 1 to increase the efficiency of mitigating arc discharge, in some embodiments of the present application, such as Figure 5 As shown, Figure 5 is a side view of the battery module. Figure 5 Only one battery cell is drawn in the figure, the multiple battery cells 40 are arranged in the shell 7, and the gas release part 5 is also arranged around the inner wall of the shell 7. In this way, when the gas release part 5 releases the non-combustible gas to the multiple battery cells 40, the non-combustible gas surrounds the multiple battery cells 40 in the shell 7, quickly discharges the ionization generated in the battery module 1, and isolates the battery cell 40 from the air of the external environment for a short time, slows down the arc discharge effect, and prevents the battery module 1 from burning on a large scale.

[0026] In some embodiments of the present application, the release temperature is greater than the operating temperature of the multiple battery cells 40 and less than the temperature at which the multiple battery cells 40 undergo thermal runaway. In this way, the gas release portion 5 will not release non-flammable gas when the battery module 1 is operating normally, and can prevent the battery module 1 from burning after the abnormal operating temperature of the battery module 1 occurs and before the temperature at which the battery cell 40 undergoes thermal runaway. The operating temperature of the multiple battery cells 40 is between 80-100°C, and the temperature at which the multiple battery cells 40 undergo thermal runaway is less than 250-300°C.

[0027] In some embodiments of the present application, the gas release part 5 is a carbonic acid raw material. More specifically, the carbonic acid raw material is sodium bicarbonate, and the sodium bicarbonate begins to produce the following reaction above the release temperature:

[0028] 2NaHCO 3 →Na 2 CO 3 +H 2 O+CO 2 ↑

[0029] In other words, sodium bicarbonate gradually decomposes to form sodium carbonate (Na 2 CO 3 ), the non-combustible gas and water (H 2 O), wherein the release temperature is 127°C, and the non-flammable gas is carbon dioxide (CO 2 ). Furthermore, 2 grams of sodium bicarbonate can produce 1 liter of carbon dioxide under the above-release temperature environment, so the above reaction can be used to effectively dilute the ionized gas, thereby reducing the high heat generated by ionized discharge and preventing the battery module 1 from burning on a large scale.

[0030] In summary, before thermal runaway occurs in the battery module 1 or before the operating temperature of the battery module 1 becomes abnormal to the point where thermal runaway occurs, the battery module 1 of the present application releases non-flammable gas through the gas release portion 5 to dilute the ionization generated in the battery module 1, thereby slowing down and terminating the arc discharge effect.

[0031] The above is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application. Therefore, all equivalent changes and modifications based on the shape, structure, characteristics and spirit described in the claims of the present application should be included in the scope of the claims of the present application.

Claims

1. A battery module, It is characterized in that include: A battery cell group, wherein the battery cell group has a plurality of battery cells, and the plurality of battery cell groups are electrically connected; as well as At least one gas release portion is arranged at at least one end of the battery cell group, and the gas release portion has a release temperature value. When the temperature of the battery cell group is greater than the release temperature value, the gas release portion releases non-flammable gas to the battery cell group to suppress the arc discharge effect of the battery cell group.

2. The battery module according to claim 1, It is characterized in that The at least one gas release portion comprises a first gas release portion and a second gas release portion, which are respectively arranged at two ends of the battery cell group.

3. The battery module according to claim 1, It is characterized in that The plurality of battery cells are arranged in a shell, and the gas release portion is also arranged around the inner wall of the shell.

4. The battery module according to claim 1, It is characterized in that The release temperature is greater than the operating temperature of the plurality of battery cells and less than the temperature at which thermal runaway occurs in the plurality of battery cells.

5. The battery module according to claim 1, It is characterized in that The gas release part is a carbonic acid raw material.

6. The battery module according to claim 5, It is characterized in that The carbonate raw material is sodium bicarbonate, and when the temperature of the battery cell group is greater than the release temperature value, the sodium bicarbonate decomposes into sodium carbonate, the non-combustible gas and water in the gas release part, wherein the non-combustible gas is carbon dioxide.

7. The battery module according to claim 6, It is characterized in that The release temperature is above 127°C.

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