Test protection device

Abstract

The utility model provides a test protection device. The test protection device is arranged between a battery pack and a charging and discharging device, the battery pack comprises a first interface and a second interface, the charging and discharging device comprises a third interface and a fourth interface, the test protection device comprises an energy release circuit, and one end of the energy release circuit is electrically connected with the first interface and the third interface; the second end of the energy release circuit is electrically connected with the second interface and the fourth interface. Wherein when the charging and discharging switch of the battery pack is configured to be switched from a closed state to an open state, the stored energy of the charging and discharging device is configured to be released along the first end of the energy release circuit and the second end of the energy release circuit in sequence.

Description

Technical Field

[0001] The present application relates to the technical field of battery testing, and in particular to a testing protection device. Background Art

[0002] Design Verification Testing (DVT) is a critical step in the product development process. Its primary purpose is to ensure that the product design meets functional and performance requirements, identify design flaws and deficiencies, and provide a basis for product improvement. Battery pack DVT is a crucial stage in the R&D process for new battery technologies.

[0003] In related technologies, the battery management system of a battery pack is easily damaged during the DVT process, resulting in low test efficiency and high test costs. Utility Model Content

[0004] An embodiment of the present application provides a test protection device, which is intended to effectively protect the BMS of a battery pack and prevent the BMS from being damaged during the DVT process, thereby improving test efficiency and reducing test costs.

[0005] An embodiment of the present application provides a test protection device, which is provided between a battery pack and a charging and discharging device. The battery pack includes a first interface and a second interface, and the charging and discharging device includes a third interface and a fourth interface. The test protection device includes:

[0006] an energy release circuit, wherein a first end of the energy release circuit is electrically connected to the first interface and the third interface respectively, and a second end of the energy release circuit is electrically connected to the second interface and the fourth interface respectively;

[0007] Among them, when the charge and discharge switch of the battery pack is configured to switch from a closed state to an open state, the stored energy of the charge and discharge device is configured to be released in sequence along the first end of the energy release circuit and the second end of the energy release circuit.

[0008] In one embodiment, the energy release circuit includes a switch circuit and at least one branch release path;

[0009] In which, the switching circuit includes a first end and a second end, the first end of the switching circuit is electrically connected to the first interface and the third interface respectively, the second end of the switching circuit is electrically connected to one end of the branch release path, and the other end of the branch release path is electrically connected to the second interface and the fourth interface respectively.

[0010] In one embodiment, the energy release circuit includes two branch release paths, namely a first branch path and a second branch path, and the switch circuit further includes a third terminal;

[0011] The first end of the first branch path is electrically connected to the second end of the switch circuit, the first end of the second branch path is electrically connected to the third end of the switch circuit, and the second end of the first branch path and the second end of the second branch path are electrically connected to the second interface and the fourth interface respectively.

[0012] In one embodiment, the switching circuit includes a switch;

[0013] The first end of the switch is electrically connected to the first interface and the third interface, the second end of the switch is electrically connected to the first end of the first branch path, and the third end of the switch is electrically connected to the first end of the second branch path.

[0014] In one embodiment, the switch comprises a single-pole double-throw switch.

[0015] In one embodiment, the first branch path includes a first bidirectional transient diode, and the second branch path includes a second bidirectional transient diode;

[0016] The first end of the first bidirectional transient diode is electrically connected to the second end of the switch circuit, the first end of the second bidirectional transient diode is electrically connected to the third end of the switch circuit, and the second end of the first bidirectional transient diode and the second end of the second bidirectional transient diode are electrically connected to the second interface and the fourth interface, respectively.

[0017] In one embodiment, the switch circuit further includes a third bidirectional transient diode;

[0018] The first end of the third bidirectional transient diode is electrically connected to the first interface and the third interface respectively, and the second end of the third bidirectional transient diode is electrically connected to the first end of the first branch path and the first end of the second branch path respectively.

[0019] In one embodiment, the sum of the breakdown voltage of the first bidirectional transient diode and the breakdown voltage of the third bidirectional transient diode is greater than a preset first test voltage, and the sum of the breakdown voltage of the second bidirectional transient diode and the breakdown voltage of the third bidirectional transient diode is greater than a preset second test voltage.

[0020] In one embodiment, the clamping voltage of the energy release circuit is lower than a preset safety voltage.

[0021] In one embodiment, the battery pack includes a fourth bidirectional transient diode;

[0022] Beneficial effects of the embodiments of the present application:

[0023] In an embodiment of the present application, a test protection device is provided, which can be arranged between a battery pack and a charging and discharging device, wherein the first end of the energy release circuit in the test protection device is electrically connected to the first interface and the third interface, respectively, and the second end of the energy release circuit is electrically connected to the second interface and the fourth interface, respectively, so that when the charge and discharge switch of the battery pack is configured to switch from a closed state to an open state, the stored energy of the charging and discharging device is configured to be released in sequence along the first end and the second end of the energy release circuit, thereby providing protection for the battery pack during the DVT process and preventing the battery tube management system in the battery pack from being damaged. Therefore, the stability of the test process is improved, and the technical problems of low test efficiency and high test cost are solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 is a schematic block diagram of a test protection device provided in an embodiment of the present application;

[0026] Figure 2 is a schematic block diagram of an energy release circuit provided in an embodiment of the present application;

[0027] Figure 3 is a circuit diagram of an energy release circuit provided in an embodiment of the present application;

[0028] Figure 4 is a circuit diagram of an application test protection device provided by an embodiment of the present application;

[0029] Figure 5 This is a circuit diagram of another application test protection device provided by an embodiment of the present application.

[0030] Description of attached mark:

[0031] Testing protection device 100;

[0032] Energy release circuit 101, switch circuit 102,

[0033] The first branch passage 103, the second branch passage 104,

[0034] a first terminal b1 of the switch circuit, a second terminal b2 of the switch circuit, and a third terminal b3 of the switch circuit,

[0035] Switching switch S1, first bidirectional transient diode TVS1, second bidirectional transient diode TVS2, third bidirectional transient diode TVS3;

[0036] Battery pack 200;

[0037] First interface a1, second interface a2,

[0038] Charge and discharge switch M1, fourth bidirectional transient diode TVS4;

[0039] Charge and discharge device 300;

[0040] The third interface a3, the fourth interface a4; DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; and "inside" and "outside" refer to the outline of the device.

[0042] Since the battery management system (BMS) of the battery pack is easily damaged during the DVT process in the related art, the test efficiency is low and the test cost is high. Specifically, Figure 5 The low-voltage battery pack (e.g. 12V / 48V) shown in the figure will store energy during the DVT process due to the parasitic inductance L1 (L2) and capacitance C1 in the charging and discharging devices and test cables and other test equipment. When the battery pack is tested, the charge and discharge switch M1 (main circuit MOS) of the battery management system in the battery pack is cut off. The energy stored in the parasitic inductance and capacitance needs to be released. In many scenarios, the stored energy will pass through the battery management system, and this stored energy will be released in a short time. Figure 5The Y direction in the diagram causes transient energy impact on the battery management system, which may cause damage to the battery management system. To this end, the following two methods are adopted in related technologies: the first is to replace the test equipment, such as replacing the charging and discharging device, cables, etc. to reduce the parasitic parameters, thereby reducing energy storage and thus reducing the impact on the battery management system. The disadvantage is that it will affect the test progress, and it is often not easy to select suitable equipment, which is very limited; the second is to add protective measures at the BMS board level, such as adding an energy release circuit, such as TVS protection devices, etc. The disadvantage is that it will increase unnecessary costs and redundant designs. To this end, an embodiment of the present application provides a test protection device, which can be arranged between a battery pack and a charging and discharging device, wherein the first end of the energy release circuit in the test protection device is electrically connected to the first interface and the third interface, respectively, and the second end of the energy release circuit is electrically connected to the second interface and the fourth interface, respectively, so that when the charge and discharge switch of the battery pack is configured to switch from a closed state to an open state, the stored energy of the charging and discharging device is configured to be released in sequence along the first end and the second end of the energy release circuit, thereby providing protection for the battery pack during the DVT process and preventing the battery tube management system in the battery pack from being damaged. Therefore, the stability of the test process is improved, and the technical problems of low test efficiency and high test cost are solved. For specific solutions, please refer to the following specific description.

[0043] It should be noted that, in the following text, the terms "battery module", "battery", "battery element", "battery cell" and "battery pack" can be used interchangeably and can refer to any of a variety of rechargeable battery chemistries and structures, including but not limited to lithium ion (such as lithium ion phosphate, lithium cobalt oxide, lithium iron phosphate, other lithium metal oxides, etc.), lithium ion polymer, nickel metal hydride, nickel cadmium, nickel hydrogen, nickel zinc, silver zinc or other battery types / structures.

[0044] For details, please refer to Figure 1 , Figure 1 This is a schematic block diagram of a test protection device provided in an embodiment of the present application. The test protection device 100 is arranged between a battery pack 200 and a charge and discharge device 300. The battery pack 200 includes a first interface a1 and a second interface a2. The charge and discharge device 300 includes a third interface a3 and a fourth interface a4.

[0045] The test protection device 100 includes: an energy release circuit 101, the first end of the energy release circuit 101 is electrically connected to the first interface a1 and the third interface a3, respectively, and the second end of the energy release circuit 101 is electrically connected to the second interface a2 and the fourth interface a4, respectively; wherein, when the charge and discharge switch M1 of the battery pack 200 is configured to switch from a closed state to an open state (normally, when the battery pack 200 completes the test or completes a certain stage of the test, the charge and discharge switch M1 of the battery pack 200 will be switched from a closed state to an open state), the stored energy of the charge and discharge device 300 is configured to be released in sequence along the first end of the energy release circuit 101 and the second end of the energy release circuit 101.

[0046] In this embodiment, during the DVT process, the test equipment will be set with a corresponding test voltage. In order to ensure that the energy release circuit 101 can provide protection for the battery management system, the breakdown voltage of the energy release circuit 101 needs to be higher than the test voltage, and the clamping voltage of the energy release circuit 101 is lower than the preset safety voltage.

[0047] The safety voltage may be set according to the highest withstand voltage of the subsequent circuit connected in parallel with the energy release circuit 101 , and the safety voltage may be lower than the highest withstand voltage of the subsequent circuit.

[0048] In an embodiment of the present application, a test protection device 100 is provided, which can be arranged between the battery pack 200 and the charging and discharging device 300, wherein the first end of the energy release circuit 101 in the test protection device 100 is electrically connected to the first interface a1 and the third interface a3, respectively, and the second end of the energy release circuit 101 is electrically connected to the second interface a2 and the fourth interface a4, respectively, so that when the charge and discharge switch M1 of the battery pack 200 is configured to switch from a closed state to an open state, the stored energy of the charging and discharging device 300 is configured to be sequentially as follows: Figure 4 The energy is released along the first end of the energy release circuit 101 and the second end of the energy release circuit 101 in the middle X direction, thereby providing protection for the battery pack 200 during the DVT process and preventing the battery tube management system in the battery pack 200 from being damaged. Therefore, the stability of the test process is improved and the technical problems of low test efficiency and high test cost are solved.

[0049] In some embodiments, as Figure 2 As shown, the energy release circuit 101 includes a switch circuit 102 and at least one branch release path.

[0050] In which, the switching circuit 102 includes a first end and a second end, the first end b1 of the switching circuit 102 is electrically connected to the first interface a1 and the third interface a3 respectively, the second end b2 of the switching circuit 102 is electrically connected to the first end of the branch release path, and the second end of the branch release path is electrically connected to the second interface a2 and the fourth interface a4 respectively.

[0051] In an embodiment of the present application, by setting at least one branch release path in the energy release circuit 101 and cooperating with the switching circuit 102, protection can be provided for the battery pack 200 during the DVT process to prevent the battery tube management system in the battery pack 200 from being damaged. Therefore, the stability during the test process is improved and the technical problems of low test efficiency and high test cost are solved.

[0052] In some embodiments, as Figure 2 As shown, the energy release circuit 101 includes two branch release paths, namely a first branch path 103 and a second branch path 104, and the switch circuit 102 further includes a third terminal;

[0053] Among them, the first end of the first branch path 103 is electrically connected to the second end b2 of the switching circuit 102, the first end of the second branch path 104 is electrically connected to the third end b3 of the switching circuit 102, and the second end of the first branch path 103 and the second end of the second branch path 104 are electrically connected to the second interface a2 and the fourth interface a4 respectively.

[0054] In the embodiment of the present application, by setting two branch release paths in the energy release circuit 101 and cooperating with the switch circuit 102, better protection can be provided for the battery pack 200 during the DVT process, preventing the battery tube management system in the battery pack 200 from being damaged. Therefore, the stability of the test process is improved and the technical problems of low test efficiency and high test cost are solved.

[0055] In some embodiments, the switch circuit 102 includes a switch S1;

[0056] The first end of the switch S1 is electrically connected to the first interface a1 and the third interface a3 , the second end of the switch S1 is electrically connected to the first end of the first branch path 103 , and the third end of the switch S1 is electrically connected to the first end of the second branch path 104 .

[0057] Among them, the breakdown voltage corresponding to the first branch path 103 is greater than the preset first test voltage, and the clamping voltage corresponding to the first branch path 103 is less than the preset first safety voltage; the breakdown voltage corresponding to the second branch path 104 is greater than the preset second test voltage, and the clamping voltage corresponding to the second branch path 104 is less than the preset second safety voltage.

[0058] In an embodiment of the present application, by setting the switching circuit 102 to a switching switch S1, different branch release paths in the energy release circuit 101 can be selected by switching the switch S1 (the breakdown voltage and clamping voltage of each branch release path may be the same or different). Different branch release paths with the same breakdown voltage and clamping voltage can facilitate fault replacement. For example, when one of the branch release paths fails, another branch release path with the same breakdown voltage and clamping voltage can be selected for replacement. In addition, different branch release paths with different breakdown voltages and clamping voltages can realize switching of different test voltages. For example, when performing a 12V low-voltage test, the corresponding branch release path can be selected by switching the switch S1. When performing a 48V low-voltage test, the corresponding branch release path can be selected by switching the switch S1. In this way, one test protection device 100 can be used to realize the protection of battery management systems with two different test voltages (for example, 12V and 48V), which is universal in low-voltage battery management system application scenarios.

[0059] In a specific embodiment, if Figure 3 As shown, the switch S1 may include a single-pole double-throw switch, wherein the single-pole double-throw switch can change the connection state of the electric shock through manual or automatic operation, thereby realizing the selection and switching of different connection modes of the circuit.

[0060] In some embodiments, at least one branch release path may also include three branch release paths or more than three branch release paths, and the corresponding switching switch S1 may select a single-pole three-throw switch or a single-pole multi-throw switch to realize a test protection device 100 with more different test voltages.

[0061] In a specific embodiment, if Figure 3 As shown, the first branch path 103 includes a first bidirectional transient diode TVS1, and the second branch path 104 includes a second bidirectional transient diode TVS2;

[0062] Among them, the first end of the first bidirectional transient diode TVS1 is electrically connected to the second end b2 of the switching circuit 102, the first end of the second bidirectional transient diode TVS2 is electrically connected to the third end b3 of the switching circuit 102, and the second end of the first bidirectional transient diode TVS1 and the second end of the second bidirectional transient diode TVS2 are electrically connected to the second interface a2 and the fourth interface a4, respectively.

[0063] In some embodiments, the switch circuit 102 further includes a third bidirectional transient diode TVS3;

[0064] The first end of the third bidirectional transient diode TVS3 is electrically connected to the first interface a1 and the third interface a3 respectively, and the second end of the third bidirectional transient diode TVS3 is electrically connected to the first end of the switch S1.

[0065] In some embodiments, the sum of the breakdown voltage of the first bidirectional transient diode TVS1 and the breakdown voltage of the third bidirectional transient diode TVS3 is greater than a preset first test voltage, and the sum of the breakdown voltage of the second bidirectional transient diode TVS2 and the breakdown voltage of the third bidirectional transient diode TVS3 is greater than a preset second test voltage.

[0066] In a specific embodiment, the first bidirectional transient diode TVS1 is a Bourns TVS model 5.0SMDJ40CA-Q, and the second bidirectional transient diode TVS2 and the third bidirectional transient diode TVS3 are respectively selected as Bourns TVS models 5.0SMDJ12CA-Q.

[0067] Among them, Bourns' TVS model is 5.0SMDJ40CA-Q. This TVS diode is a device used for ESD protection and surge protection and is packaged in DO-214AB (SMC). Its operating peak reverse voltage range is from 12V to 43V, and its breakdown voltage can reach 52.8V. In addition, this model of TVS diode meets the AEC-Q101 standard and has a fast response time, with a typical value of less than 1.0 picoseconds. In specific applications, this model of TVS diode can provide a pulse power capability of up to 5kW and is suitable for applications requiring high energy absorption. It is also designed in a low-profile surface mount form to reduce PCB space.

[0068] xx, its detailed specifications: Working peak reverse voltage (VRWM): 12V. Breakdown voltage range: from 12V to 43V, depending on the different product versions. Clamping voltage: up to 19.9V.

[0069] Current pulse withstand (Ipp): 252A. Power handling capacity: 5kW. Package type: DO-214AB (SMC) surface mount package. Temperature coefficient: ΔVBR = 0.1% x V.

[0070] In some embodiments, as Figure 4 As shown, the battery pack 200 includes a fourth bidirectional transient diode TVS4;

[0071] The first end of the fourth bidirectional transient diode TVS4 is electrically connected to the first end of the charge and discharge switch M1 and the first interface a1, respectively, and the second end of the fourth bidirectional transient diode TVS4 is electrically connected to the second interface a2.

[0072] In an embodiment of the present application, a fourth bidirectional transient diode TVS4 is provided in the battery pack 200. Specifically, the fourth bidirectional transient diode TVS4 is provided between the first interface a1 and the second interface a2 of the battery management system and the battery pack 200, thereby adding another layer of protection to the battery management system and further improving the stability of the battery pack 200 in DVT.

[0073] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A test protection device, characterized in that: It is provided between the battery pack and the charging and discharging device, the battery pack includes a first interface and a second interface, the charging and discharging device includes a third interface and a fourth interface, and the test protection device includes: an energy release circuit, wherein a first end of the energy release circuit is electrically connected to the first interface and the third interface respectively, and a second end of the energy release circuit is electrically connected to the second interface and the fourth interface respectively; Among them, when the charge and discharge switch of the battery pack is configured to switch from a closed state to an open state, the stored energy of the charge and discharge device is configured to be released in sequence along the first end of the energy release circuit and the second end of the energy release circuit.

2. The test protection device according to claim 1, characterized in that: The energy release circuit includes a switch circuit and at least one branch release path; In which, the switching circuit includes a first end and a second end, the first end of the switching circuit is electrically connected to the first interface and the third interface respectively, the second end of the switching circuit is electrically connected to the first end of the branch release path, and the second end of the branch release path is electrically connected to the second interface and the fourth interface respectively.

3. The test protection device according to claim 2, characterized in that: The energy release circuit includes two branch release paths, namely a first branch path and a second branch path, and the switch circuit further includes a third terminal; The first end of the first branch path is electrically connected to the second end of the switch circuit, the first end of the second branch path is electrically connected to the third end of the switch circuit, and the second end of the first branch path and the second end of the second branch path are electrically connected to the second interface and the fourth interface respectively.

4. The test protection device according to claim 3, characterized in that: The switching circuit includes a switching switch; The first end of the switch is electrically connected to the first interface and the third interface, the second end of the switch is electrically connected to the first end of the first branch path, and the third end of the switch is electrically connected to the first end of the second branch path.

5. The test protection device according to claim 4, characterized in that: The switch comprises a single-pole double-throw switch.

6. The test protection device according to claim 4, characterized in that: The first branch path includes a first bidirectional transient diode, and the second branch path includes a second bidirectional transient diode; The first end of the first bidirectional transient diode is electrically connected to the second end of the switch circuit, the first end of the second bidirectional transient diode is electrically connected to the third end of the switch circuit, and the second end of the first bidirectional transient diode and the second end of the second bidirectional transient diode are electrically connected to the second interface and the fourth interface, respectively.

7. The test protection device according to claim 6, characterized in that: The switch circuit further includes a third bidirectional transient diode; The first end of the third bidirectional transient diode is electrically connected to the first interface and the third interface respectively, and the second end of the third bidirectional transient diode is electrically connected to the first end of the switch.

8. The test protection device according to claim 7, characterized in that: The sum of the breakdown voltage of the first bidirectional transient diode and the breakdown voltage of the third bidirectional transient diode is greater than a preset first test voltage, and the sum of the breakdown voltage of the second bidirectional transient diode and the breakdown voltage of the third bidirectional transient diode is greater than a preset second test voltage.

9. The test protection device according to any one of claims 1 to 8, characterized in that: The clamping voltage of the energy release circuit is lower than a preset safety voltage.

10. The test protection device according to any one of claims 1 to 8, characterized in that: The battery pack includes a fourth bidirectional transient diode; The first end of the fourth bidirectional transient diode is electrically connected to the first end of the charge and discharge switch and the first interface respectively, and the second end of the fourth bidirectional transient diode is electrically connected to the second interface.

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