Battery pack, battery management system, and battery system

Abstract

The utility model discloses a kind of battery pack, battery management system and battery system, battery pack includes: upper cover and lower shell, upper cover and lower shell define containing cavity, containing cavity is used to contain multiple electric core, and upper cover is equipped with high voltage distribution maintenance opening with opening direction lower shell;Detection circuit, comprising: first normally closed switch, set on high voltage distribution maintenance opening, when high voltage distribution maintenance opening is opened, first normally closed switch is disconnected;Second normally closed switch, set between upper cover and lower shell, when upper cover is opened, second normally closed switch is disconnected;First resistance;Second resistance, first resistance and second resistance resistance are different;Wherein, detection circuit is used to be electrically connected with battery management system, to determine the voltage value of detection circuit, voltage value is used to determine whether the upper cover of battery pack and high voltage distribution maintenance opening is opened.According to the battery pack provided in the application, the safety of battery pack use and maintenance is effectively improved, and the safety early warning time limit is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of batteries, and in particular to a battery pack, a battery management system, and a battery system. Background Technology

[0002] With the rapid development of new energy vehicles, the safety design and early warning of power battery systems are becoming increasingly important, and battery pack operation status detection is an indispensable part of ensuring the safety of power batteries.

[0003] Currently, in order to facilitate the replacement of the main fuse and branch fuses of the power battery pack (for example, branch fuses located in the heater, air conditioning compressor, on-board charger and DC-DC converter) and reduce maintenance costs, high-voltage component maintenance ports are designed in the corresponding locations for new energy vehicles. However, this also brings certain safety failure risks. In addition, there is currently no installation status record or inspection when the power battery pack cover is removed. If its sealing design is defective or it is disassembled and repaired by non-professional maintenance personnel, there will also be certain failure risks. Utility Model Content

[0004] In a first aspect, embodiments of this application provide a battery pack, comprising:

[0005] The upper cover and the lower housing define a receiving cavity for accommodating multiple battery cells, and the upper cover has a high-voltage power distribution maintenance port with an opening facing the lower housing.

[0006] The detection circuit includes:

[0007] The first normally closed switch is installed on the high-voltage power distribution maintenance port. When the high-voltage power distribution maintenance port is opened, the first normally closed switch is disconnected.

[0008] The second normally closed switch is located between the upper cover and the lower housing. When the upper cover is opened, the second normally closed switch is disconnected.

[0009] First resistor;

[0010] The second resistor has a different resistance value than the first resistor.

[0011] The detection circuit is electrically connected to the battery management system to determine the voltage value of the detection circuit. The voltage value is used to determine whether the battery pack cover and high-voltage power distribution maintenance port have been opened.

[0012] According to the battery pack provided in this application, by setting a detection circuit, the BMS can determine the voltage value of the detection circuit, and thus determine whether the battery pack's top cover and high-voltage power distribution port are open. In other words, by converting the physical state (on / off) into an electrical signal (voltage present / absent), the BMS, as the "brain," can sense the structural integrity of the battery pack, effectively improving the safety of battery pack use and maintenance, as well as the timeliness of safety warnings. Furthermore, the high-voltage power distribution port of the battery pack faces downwards, so maintenance can be performed without removing the battery pack's top cover. Compared to existing maintenance methods that require removing the entire battery pack from the vehicle body, this significantly simplifies the maintenance process, avoids the risk of secondary damage to the battery pack structure, and ensures the large-area sealing performance of the battery pack's top cover.

[0013] Secondly, embodiments of this application provide a battery management system for electrical connection to a battery pack as described in the first aspect, comprising:

[0014] Pull-up voltage;

[0015] The third resistor is connected in series with the pull-up voltage;

[0016] The control unit is equipped with a temperature acquisition port, which is used by the control unit to determine the voltage value of the detection circuit. The voltage value is used to determine whether the top cover of the battery pack and the high-voltage power distribution maintenance port have been opened.

[0017] In some embodiments, a voltage detection point is provided at the end of the third resistor that is not connected to the pull-up voltage, and the control unit determines the voltage value of the detection circuit by detecting the voltage at the voltage detection point.

[0018] In some embodiments, the system includes a filter resistor, one end of which is connected to a voltage detection point, and the other end of which is connected to a control unit.

[0019] In some embodiments, including:

[0020] A first filter capacitor, one end of which is connected to one end of a filter resistor, and the other end of which is grounded; and / or

[0021] The second filter capacitor has one end connected to the other end of the filter resistor, and the other end is grounded.

[0022] Thirdly, embodiments of this application provide a battery system, comprising:

[0023] Such as the battery pack in the first aspect; and

[0024] Such as the battery management system in the second aspect.

[0025] In some embodiments, when neither the top cover nor the high-voltage power distribution maintenance port is opened, the third resistor is connected in parallel with the first resistor and the second resistor, and then connected in series.

[0026] In some embodiments, when the high-voltage power distribution maintenance port is opened but the top cover is not opened, the third resistor is connected in series with the second resistor.

[0027] In some embodiments, when the top cover is opened but the high-voltage power distribution maintenance port is not opened, the third resistor is connected in series with the first resistor.

[0028] In some embodiments, the first resistor is 6.2 kΩ; and / or, the second resistor is 4.3 kΩ; and / or, the third resistor is 5.6 kΩ; and / or, the pull-up voltage is 3.3 V; and / or, the filter resistor is 10 kΩ; and / or, the first filter capacitor is 10 nanofarads; and / or, the second filter capacitor is 47 nanofarads. Attached Figure Description

[0029] Figure 1 A schematic diagram of a battery pack provided according to some embodiments of this application is shown;

[0030] Figure 2 A circuit diagram of a battery system including a detection circuit according to some embodiments of this application is shown. Detailed Implementation

[0031] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model will be presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to this embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. To provide a deep understanding of this utility model, many specific details will be included in the following description. This utility model may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0032] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0034] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0036] Firstly, reference Figure 1 This application provides a battery pack, including an upper cover and a lower housing. The upper cover and the lower housing define a receiving cavity for accommodating multiple battery cells. The upper cover also has a high-voltage power distribution maintenance port with an opening facing the lower housing.

[0037] refer to Figure 2 The battery pack also includes: a detection circuit 100 (e.g., as shown in the image). Figure 2 (The connector input port is shown). The detection circuit 100 includes a first normally closed switch 11, a second normally closed switch 8, a first resistor 12, and a second resistor 7. The first normally closed switch 11 is located on the high-voltage power distribution maintenance port; when the high-voltage power distribution maintenance port is opened, the first normally closed switch 11 is open. The second normally closed switch 8 is located between the upper cover and the lower housing; when the upper cover is opened, the second normally closed switch 8 is open. The first resistor 12 and the second resistor 7 have different resistance values. The detection circuit 100 is electrically connected to the Battery Management System (BMS) 1 to determine the voltage value of the detection circuit 100. The voltage value is used to determine whether the upper cover of the battery pack and the high-voltage power distribution maintenance port are open.

[0038] According to the battery pack provided in this application, by setting up a detection circuit 100, the BMS can determine the voltage value of the detection circuit 100, and thus determine whether the top cover and high-voltage distribution port of the battery pack have been opened. In other words, by converting the physical state (open / closed) into an electrical signal (voltage present / absent), the BMS, as the "brain," can sense the structural integrity of the battery pack, effectively improving the safety of battery pack use and maintenance, as well as the timeliness of safety warnings. For example, once the system detects that the top cover has been illegally opened, it can immediately trigger an alarm (such as notifying the administrator through a cloud platform), or even actively prevent the battery pack from starting / charging, preventing unauthorized personnel from contacting high-voltage components and avoiding the risk of electric shock or unauthorized modification; or, in professional maintenance scenarios, when technicians open the high-voltage distribution port to perform work, the BMS can sense this state, and the system can force entry into "maintenance mode" to ensure that the internal high-voltage relay has been disconnected, providing an electrical safety confirmation, which is equivalent to adding an "electronic safety lock" to protect the safety of technicians. In addition, the high-voltage distribution port is part of the high-voltage circuit, and this design can be regarded as a key link in the high-voltage interlock circuit. If the power distribution port is opened, it means that the integrity of the high-voltage circuit has been compromised. The BMS will immediately detect this and implement fail-safe policies, such as cutting off the high-voltage power to prevent dangers such as electric arcs caused by unreliable connections.

[0039] Furthermore, the high-voltage power distribution maintenance port of the battery pack faces downwards, so maintenance can be carried out without removing the battery pack cover. Compared with the existing maintenance, which requires removing the entire battery pack from the vehicle body, this greatly simplifies the maintenance process, avoids the risk of secondary damage to the battery pack structure, and ensures the large-area sealing performance of the battery pack cover.

[0040] Secondly, refer to Figure 2 This application provides a battery management system 1 for electrical connection to a battery pack as described in the first aspect. The battery management system 1 includes: a pull-up voltage 2, a third resistor 3 connected in series with the pull-up voltage, and a control unit. The control unit is provided with a temperature acquisition port (e.g., as shown in the first aspect). Figure 2 The connector input port shown is used by the control unit to determine the voltage value of the detection circuit 100. The voltage value is used to determine whether the top cover of the battery pack and the high-voltage power distribution maintenance port are open.

[0041] In some embodiments, the end of the third resistor 3 that is not connected to the pull-up voltage is provided with a voltage detection point Vt, and the control unit determines the voltage value of the detection circuit 100 by detecting the voltage at the voltage detection point Vt.

[0042] In some embodiments, the battery management system 1 further includes a filter resistor 4. One end of the filter resistor 4 is connected to the voltage detection point Vt, and the other end of the filter resistor 4 is connected to the control unit.

[0043] In some embodiments, the battery management system 1 further includes: a first filter capacitor 6 and / or a second filter capacitor 5. One end of the first filter capacitor 6 is connected to one end of the filter resistor 4, and the other end of the first filter capacitor 6 is grounded; one end of the second filter capacitor 5 is connected to the other end of the filter resistor 4, and the other end of the second filter capacitor 5 is grounded.

[0044] According to the battery management system 1 provided in this application, based on the existing temperature acquisition port, and in conjunction with the battery pack equipped with the detection circuit 100, the voltage value of the detection circuit 100 can be determined, thereby determining whether the top cover of the battery pack and the high-voltage power distribution maintenance port are open. Since the battery management system 1 does not require additional adapter ports, components, or circuits, it saves the detection resources of the battery management system 1 and effectively increases the number of detection channels.

[0045] Thirdly, this application also provides a battery system, including: a battery pack as described in the first aspect; and a battery management system 1 as described in the second aspect.

[0046] In some embodiments, when neither the top cover nor the high-voltage power distribution maintenance port is opened, the third resistor 3 is connected in parallel with the first resistor 12 and the second resistor 7, and then connected in series.

[0047] In some embodiments, when the high-voltage power distribution maintenance port is opened but the top cover is not opened, the third resistor 3 is connected in series with the second resistor 7.

[0048] In some embodiments, when the top cover is opened but the high-voltage power distribution maintenance port is not opened, the third resistor 3 is connected in series with the first resistor 12.

[0049] For example, the first resistor 12 has a voltage of 6.2 kΩ, the second resistor 7 has a voltage of 4.3 kΩ, the third resistor 3 has a voltage of 5.6 kΩ, the pull-up voltage is 3.3 V, the filter resistor 4 has a voltage of 10 kΩ, the first filter capacitor 6 has a voltage of 10 nanofarads, and the second filter capacitor 5 has a voltage of 47 nanofarads. It should be noted that the parameters of the above components can be changed according to actual needs, and no specific limitations are imposed.

[0050] The following example uses resistor 12 as 6.2 kΩ, resistor 7 as 4.3 kΩ, resistor 3 as 5.6 kΩ, and pull-up voltage as 3.3 V to illustrate the voltage values ​​corresponding to the voltage detection point Vt under each state.

[0051] When neither the top cover nor the high-voltage power distribution maintenance port is opened, i.e. the first normally closed switch 11 and the second normally closed switch 8 are still closed, the current flows out from the pull-up voltage 2, through the third resistor 3, the first resistor 12 and the second resistor 7 (which are connected in parallel), and then through the connecting line 10 and the ground wire 9 to the ground. The 2.54 kΩ is the resistance of the first resistor (126.2 kΩ) and the second resistor (74.3 kΩ) connected in parallel.

[0052] When the high-voltage power distribution maintenance port is opened but the top cover is not opened, that is, the first normally closed switch 11 is open and the second normally closed switch 8 is still closed. The current flows out from the pull-up voltage 2, through the third resistor 3 and the second resistor 7, and then through the connecting line 10 and the ground wire 9 to the ground. .

[0053] When the top cover is opened but the high-voltage power distribution maintenance port is not opened, that is, the second normally closed switch 8 is open and the first normally closed switch 11 is still closed. The current flows out from the pull-up voltage 2, through the third resistor 3 and the first resistor 12, and then through the connecting line 10 and the ground wire 9 to the ground. .

[0054] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A battery pack, characterized in that, include: The upper cover and the lower housing define a receiving cavity for accommodating multiple battery cells, and the upper cover is provided with a high-voltage power distribution maintenance port with an opening facing the lower housing; The detection circuit includes: A first normally closed switch is installed on the high-voltage power distribution maintenance port. When the high-voltage power distribution maintenance port is opened, the first normally closed switch is disconnected. A second normally closed switch is disposed between the upper cover and the lower housing. When the upper cover is opened, the second normally closed switch is disconnected. First resistor; The second resistor has a different resistance value than the first resistor; The detection circuit is electrically connected to the battery management system to determine the voltage value of the detection circuit. The voltage value is used to determine whether the top cover of the battery pack and the high-voltage power distribution maintenance port are opened.

2. A battery management system, characterized in that, For electrical connection with the battery pack as described in claim 1, comprising: Pull-up voltage; The third resistor is connected in series with the pull-up voltage; The control unit is equipped with a temperature acquisition port, which is used by the control unit to determine the voltage value of the detection circuit. The voltage value is used to determine whether the top cover of the battery pack and the high-voltage power distribution maintenance port are opened.

3. The battery management system as described in claim 2, characterized in that, The third resistor has a voltage detection point at the end that is not connected to the pull-up voltage. The control unit determines the voltage value of the detection circuit by detecting the voltage at the voltage detection point.

4. The battery management system as described in claim 3, characterized in that, include: A filter resistor, one end of which is connected to the voltage detection point, and the other end of which is connected to the control unit.

5. The battery management system as described in claim 4, characterized in that, include: A first filter capacitor, one end of which is connected to one end of the filter resistor, and the other end of which is grounded; And / or, The second filter capacitor has one end connected to the other end of the filter resistor, and the other end of the second filter capacitor is grounded.

6. A battery system, characterized in that, include: The battery pack as described in claim 1; and The battery management system as described in any one of claims 2 to 5.

7. The battery system as claimed in claim 6, characterized in that, When neither the top cover nor the high-voltage power distribution maintenance port is opened, the third resistor is connected in parallel with the first resistor and the second resistor, and then connected in series.

8. The battery system as claimed in claim 7, characterized in that, When the high-voltage power distribution maintenance port is opened and the top cover is not opened, the third resistor is connected in series with the second resistor.

9. The battery system as claimed in claim 7, characterized in that, When the top cover is opened but the high-voltage power distribution maintenance port is not opened, the third resistor is connected in series with the first resistor.

10. The battery system as claimed in claim 6, characterized in that, The first resistor is 6.2 kΩ; and / or, the second resistor is 4.3 kΩ; and / or, the third resistor is 5.6 kΩ; and / or, the pull-up voltage is 3.3 V; and / or, the filter resistor is 10 kΩ; and / or, the first filter capacitor is 10 nanofarads; and / or, the second filter capacitor is 47 nanofarads.

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