Insulation test device, system and test method

Abstract

The invention provides an insulation test device, system and test method, and relates to the technical field of battery detection, the device comprises a connector and a contact structure, the connector is connected with the contact structure, and the contact structure is used for being in contact with a to-be-tested battery shell; a power supply end is arranged in the connector, and the power supply end is used for being connected with a charge-discharge port of a to-be-tested battery; an insulation test circuit is arranged in the connector, one end of the insulation test circuit is electrically connected with the contact structure, and the other end of the insulation test circuit is connected with the power supply end; the insulation test circuit comprises a switching device and a test resistor which are arranged in series, the control end of the switching device is used for receiving a control signal, and the switching device is configured to control the on or off of the insulation test circuit according to the control signal; the insulation test circuit is configured to determine the insulation performance of the to-be-tested battery based on the comparison result of the resistance value of the test resistor and the measured value. No extra grounding wire harness is needed, the topological structure of the insulation test system is simplified, and the test efficiency is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery testing, and in particular to an insulation testing device, system, and testing method. Background Art

[0002] BMU (Battery Management Unit) insulation accuracy testing is a key step in ensuring battery system safety.

[0003] In related technologies, the BMU insulation accuracy test requires an additional grounding harness to construct a reference potential point, which makes the reliance on the grounding wire too high, increases the harness cost and assembly complexity, and restricts the highly integrated design of the battery pack.

[0004] It should be noted that the above statements are only used to provide background technical information related to this application and do not necessarily constitute prior art. Summary of the Invention

[0005] In view of this, the purpose of this application is to propose an insulation testing device, system, and testing method. This application can specifically solve the problem of low integration of existing insulation testing.

[0006] Based on the above objectives, in a first aspect, the present application proposes an insulation testing device, which includes: a connector and a contact structure, the connector being connected to the contact structure, and the contact structure being used to contact the outer shell of a battery to be tested; a power supply terminal is provided in the connector, and the power supply terminal is used to connect to the charging and discharging port of the battery to be tested; an insulation testing circuit is provided inside the connector, one end of the insulation testing circuit is electrically connected to the contact structure, and the other end of the insulation testing circuit is connected to the power supply terminal; the insulation testing circuit includes a switching device and a test resistor arranged in series, the control end of the switching device is used to receive a control signal sent by an insulation detection terminal device, and the switching device is configured to control the conduction or shutdown of the insulation testing circuit according to the control signal; the insulation testing circuit is configured to determine the insulation performance of the battery to be tested based on a comparison result of the resistance value of the test resistor and a measured value, the measured value being the total resistance of the insulation resistance and the test resistor in parallel, and the insulation resistance being the resistance between the battery to be tested and the outer shell.

[0007] The test process is "plug and test" achieved by using a connector as a connection component. The contact structure establishes contact with the battery housing to establish a test circuit, eliminating the need for a grounding harness. The insulation test circuit detects insulation performance, while a switch receives a control signal to control the circuit on and off. A test resistor provides a known resistance value, allowing insulation performance to be determined by comparing the measured value with the test resistor. This simplifies the insulation test device structure, improves test efficiency, and reduces costs.

[0008] In some embodiments, the contact structure includes a first portion and a second portion, wherein the first portion is electrically connected to one end of the insulation test circuit and fixedly connected to the connector, and the second portion extends to the outside of the connector, and the end of the second portion facing away from the first portion is used to contact the battery housing to be tested.

[0009] The above embodiment provides a contact structure, which realizes fixed connection with the insulation test circuit through the first portion and realizes external contact with the battery housing to be tested through the second portion, thereby improving the stability and reliability of the test circuit.

[0010] In some embodiments, the second portion includes a conductive rod, the first portion includes a sleeve, the conductive rod is sleeved in the sleeve, and the conductive rod and the sleeve are elastically connected via a first elastic member.

[0011] The above embodiment provides a conductive rod and sleeve installation solution to achieve a wire harness-free design, with a virtual connection detection function, and achieve miniaturization and sealing compatibility.

[0012] In some embodiments, the second portion includes a second elastic member, a protrusion is provided at the end of the second elastic member facing away from the first portion, the second elastic member is connected to the first portion through an elastic actuation lever, and the elastic actuation lever is used to change the angle between the second elastic member and the horizontal direction so that the protrusion contacts the battery housing to be tested.

[0013] The above embodiment provides a contact structure solution for rotating contact through an elastic actuation lever, which can realize a wire-free design, has a virtual contact detection function, meets the needs of different scenarios, and improves the flexibility of the contact structure.

[0014] In some embodiments, the portion of the contact structure located outside the connector has an insulating layer or an insulating sleeve, so as to prevent the operator from being electrocuted by high voltage through physical isolation.

[0015] In some embodiments, the switching device includes a first switching tube, the insulation test circuit further includes a first fuse, and the first switching tube and the first fuse are connected in series.

[0016] The first switch tube and the first fuse are connected in series to form a double insurance mechanism, thereby improving the safety performance of the test circuit.

[0017] In some embodiments, the switching device includes an electronic switching unit, in which a second switching tube and a second fuse are integrated, and the second switching tube and the second fuse are connected in series.

[0018] On the one hand, it has a double insurance function, which improves the safety performance of the test circuit. On the other hand, it is further conducive to the miniaturization and sealing compatibility of the insulation test device.

[0019] In some embodiments, the control terminal of a switching transistor in the switching device is connected to an insulation detection terminal device, which is used to send a control signal to the switching transistor of the switching device. Directly connecting the control terminal of the switching transistor to the insulation detection terminal device allows for a rapid response to control signals, improving testing efficiency.

[0020] In some embodiments, the connector includes a metal area and a non-metal area, the power supply terminal is disposed in the metal area, and the contact structure and the insulation test circuit are disposed in the non-metal area, thereby achieving physical isolation and improving the anti-interference capability and stability of signal transmission.

[0021] In the second aspect, an insulation testing system is also provided, which includes a battery to be tested, an insulation testing device and an insulation detection terminal device, wherein the insulation testing device is the insulation testing device described in any one of the first aspects; the insulation testing device is in contact with the outer shell of the battery to be tested through the contact structure, and the insulation detection terminal device is used to send a control signal to the insulation testing device; the charging and discharging ports of the battery to be tested include a positive pole and a negative pole, and the positive pole and the negative pole are both provided with the insulation testing device, the battery management unit of the battery to be tested is connected to one end of the insulation testing device of the positive pole through a first relay, and the battery management unit of the battery to be tested is connected to one end of the insulation testing device of the negative pole through a second relay; the other ends of the insulation testing devices of the positive pole and the negative pole are both in contact with the outer shell of the battery to be tested through the contact structure.

[0022] In a third aspect, an insulation testing method is also provided, which is applied to the insulation testing system described in the second aspect, and the method includes: determining a port to be detected based on the on and off states of a first relay and a second relay, wherein the port to be detected is the positive or negative pole of the battery to be tested; obtaining a measurement value between the port to be detected and a contact point, wherein the contact point is the contact point between the contact structure and the outer shell of the battery to be tested; the measurement value is the total resistance of the insulation resistance and the test resistance in parallel, and the insulation resistance is the resistance between the battery to be tested and the outer shell; when the measurement value is less than the resistance of the test resistance in the insulation test circuit and the difference between the measurement value and the resistance of the test resistance is less than a preset difference, determining that the insulation performance of the battery to be tested is normal; when the difference between the measurement value and the resistance of the test resistance is greater than the preset difference, determining that the insulation performance of the battery to be tested is abnormal.

[0023] In some embodiments, when the second portion of the contact structure of the insulation testing device includes a conductive rod and the first portion includes a sleeve, the method further includes: obtaining the expansion and contraction amount of the conductive rod, the expansion and contraction amount including the overlapping length of the second portion and the first portion; when the expansion and contraction amount is greater than or equal to a preset threshold, determining that the insulation testing device is normally connected to the battery casing to be tested; when the expansion and contraction amount is less than the preset threshold, determining that the insulation testing device is abnormally connected to the battery casing to be tested.

[0024] In some embodiments, when the second portion of the contact structure of the insulation testing device is a second elastic member, the method further includes: obtaining the angle between the second elastic member and the horizontal direction; when the angle is within a preset angle range, determining that the connection between the insulation testing device and the battery casing to be tested is normal; when the angle exceeds the preset angle range, determining that the connection between the insulation testing device and the battery casing to be tested is abnormal.

[0025] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In the accompanying drawings, unless otherwise specified, identical reference numerals throughout the multiple drawings represent identical or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed herein and should not be construed as limiting the scope of this application. Furthermore, identical reference numerals are used throughout the drawings to represent identical components.

[0027] Figure 1 A schematic diagram of a wiring harness showing an insulation test structure in the prior art; Figure 2 Shows an integrated schematic diagram of an insulation testing device according to an embodiment of the present application; Figure 3 A schematic structural diagram of an insulation testing device according to an embodiment of the present application is shown; Figure 4 Another structural schematic diagram of the insulation testing device according to an embodiment of the present application is shown; Figure 5 Another structural schematic diagram of the insulation testing device according to an embodiment of the present application is shown; Figure 6 A schematic diagram showing the principle of a test circuit according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0028] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0030] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0031] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0032] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0033] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0034] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0035] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0036] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0037] The battery under test mentioned in the embodiments of this application is a battery apparatus, which may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include one or more battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0038] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is a battery module formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells using cable ties.

[0039] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0040] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0041] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0042] As an example, the housing may include a first housing and a second housing. The first housing and the second housing engage to form an enclosed space within the housing to house the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first housing may be a top cover or a bottom plate.

[0043] As an example, the box may include a top cover, a frame, and a bottom plate, wherein the top cover and the bottom plate are respectively connected to the frame to form a closed space inside the box to accommodate the battery cell assembly.

[0044] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0045] In some embodiments, the battery device refers to an energy storage device, which includes a box with a door on at least one side. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0046] In some embodiments of the present application, the battery may be, but is not limited to, a cell, a single cell, a battery module, a battery pack, an energy storage cabinet, an energy storage container, etc. The battery may be a lithium-ion battery, including but not limited to a lithium cobalt oxide battery, a lithium manganese oxide battery, a lithium nickel oxide battery, a lithium iron phosphate battery, etc. In some embodiments of the present application, the battery may be of any shape and structure, such as a cylindrical battery, a flat battery, a pouch battery, a prismatic battery, etc.

[0047] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0048] BMU (Battery Management Unit) insulation accuracy testing is a critical step in ensuring battery system safety. End of Line (EOL) testing machines are used to perform multi-dimensional electrical performance testing and functional verification of batteries, including BMU insulation accuracy testing.

[0049] Figure 1 A schematic diagram of a test structure in the prior art is shown. Figure 1As shown, in the related art, the BMU insulation accuracy test requires an additional grounding harness, and a reference potential point is constructed through the grounding harness to connect the EOL tester to the battery pack. This makes the reliance on the grounding wire too high, increases the harness cost and assembly complexity, and restricts the highly integrated design of the battery pack.

[0050] In order to solve the above problems, the present invention provides an insulation testing device. Figure 2 As shown, the insulation testing device of this embodiment can achieve a high degree of integration between the battery connector and the insulation testing circuit. Specifically, a contact structure is adopted to connect with the battery housing in a contact manner, and no additional grounding harness is required, which simplifies the topology of the insulation testing system and can achieve "plug and test" during the testing process, saving the time of connecting the harness and improving the testing efficiency.

[0051] Figure 3 Schematic diagram showing the structure of the insulation testing device according to an embodiment of the present application; Figure 3 As shown, the insulation testing device 10 of this embodiment includes: a connector 11 and a contact structure 12, wherein the connector 11 is connected to the contact structure 12, and the contact structure 12 is configured to contact the outer shell of the battery under test; a power supply terminal 13 is provided within the connector 11, and the power supply terminal 13 is configured to connect to the charge and discharge ports of the battery under test; an insulation testing circuit 14 is provided within the connector 11, one end of the insulation testing circuit 14 is electrically connected to the contact structure 12, and the other end of the insulation testing circuit 14 is connected to the power supply terminal 13; the insulation testing circuit 14 includes a switch device and a test resistor 142 arranged in series, the control end of the switch device is configured to receive a control signal sent by an insulation detection terminal device, and the switch device is configured to control the conduction or disconnection of the insulation testing circuit 14 according to the control signal. The insulation testing circuit is configured to determine the insulation performance of the battery under test based on the comparison result of the resistance value of the test resistor 142 and the measured value. The measured value is the total resistance of the insulation resistance and the test resistor in parallel, and the insulation resistance is the resistance between the battery under test and the outer shell.

[0052] In the embodiment of the present application, the connector 11 is a physical carrier that integrates power supply and insulation test functions, provides a standard interface to connect the battery to be tested with an external device (load), and then establishes a connection between the battery to be tested and the external device to realize functions such as battery power supply and insulation test.

[0053] In the embodiment of the present application, a contact structure 12 is used to replace the grounding harness in the related art, and the contact structure 12 is integrated inside the connector 11. The contact structure 12 is a conductive structure that can establish a conductive path between the battery housing and the insulation test circuit 14.

[0054] In this embodiment, an insulation test circuit 14 is provided within the connector 11. One end of the insulation test circuit 14 is electrically connected to the contact structure 12, and the other end of the insulation test circuit 14 is connected to the power supply terminal 13, thereby forming an insulation test loop. A control signal can be generated by the EOL tester to place the battery under test and the insulation test device 10 in an insulation test state.

[0055] In this embodiment, the switching device may include a semiconductor switch (such as MOSFET / IGBT). The switching device is, for example, Figure 3 The first switch tube 141 shown has a control terminal, which receives an external control signal and turns on / off the insulation test circuit 14 in response to the control signal. When turned off, the high voltage can be physically isolated to protect the EOL tester.

[0056] In this embodiment, the insulation test circuit 14 includes a switch device and a test resistor 142 arranged in series. The control end of the switch device is used to receive a control signal. The switch device is configured to control the conduction or shutdown of the insulation test circuit 14 according to the control signal. The test resistor 142 is used to provide a known resistance for comparison. By comparing the resistance value of the test resistor with the measured value, the insulation performance of the battery to be tested is determined, wherein the measured value is the total resistance of the insulation resistance and the test resistor in parallel, and the insulation resistance is the resistance between the battery to be tested and the casing.

[0057] According to the principle of parallel resistors: R measurement value =

[0058] When the insulation performance of the battery shell to be tested is normal, Infinity, the R measurement value is infinitely close to but less than the R test resistance. The resistance of the test resistor 142 can be set according to actual needs. If the test resistor 142 is 1MΩ, if the R measurement value is <1MΩ, and the measurement value is close to 1MΩ, it means that the insulation performance is normal. If the difference between the R measurement value and the R test resistance is too large, it means that the insulation performance is abnormal.

[0059] In one example, the charging and discharging ports of the battery to be tested include the positive electrode of the battery to be tested and the negative electrode of the battery to be tested. The positive electrode of the battery to be tested and the negative electrode of the battery to be tested are respectively connected to a connector 11, and a power supply terminal 13 is provided in the connector 11. Under normal power supply conditions, the positive electrode of the battery to be tested, the power supply terminal 13 of the positive connector 11, the load, the power supply terminal 13 of the negative connector 11, and the negative electrode of the battery form a charging and discharging circuit.

[0060] Under the insulation test condition, the battery shell to be tested, the positive electrode of the battery to be tested, the power supply terminal 13 of the positive connector 11, and the insulation test circuit 14 form an insulation test loop to implement the insulation performance test between the battery positive electrode and the shell.

[0061] Under the insulation test condition, the battery shell to be tested, the negative electrode of the battery to be tested, the power supply terminal 13 of the negative electrode connector 11, and the insulation test circuit 14 form an insulation test loop to implement the insulation performance test between the battery negative electrode and the shell.

[0062] The above embodiment provides an insulation testing device 10 that utilizes a connector 11 as a connection component to achieve a "plug-and-test" testing process. A contact structure 12 establishes contact with the battery housing to establish a test circuit, eliminating the need for a grounding harness. Insulation performance is monitored via an insulation testing circuit 14. A switching device receives a control signal to control the on / off of the circuit. A test resistor 142 provides a known resistance value, allowing insulation performance to be determined by comparing the measured value with the test resistor 142. This simplifies the structure of the insulation testing device 10, improves testing efficiency, and reduces costs.

[0063] In the embodiment of this application, Figure 3 As shown, the contact structure 12 includes a first portion 121 and a second portion 122. The first portion 121 is electrically connected to one end of the insulation test circuit 14 and is fixedly connected to the connector 11. The second portion 122 extends to the outside of the connector 11. The end of the second portion 122 facing away from the first portion 121 is used to contact the battery housing to be tested.

[0064] Among them, the first part 121 is electrically connected to one end of the insulation test circuit 14 and fixedly connected to the connector 11, and can serve as an internal connection point to achieve a fixed connection with the insulation test circuit 14. The second part 122 extends to the outside of the connector 11, and the end away from the first part 121 is used to contact the outer casing of the battery to be tested, thereby achieving external contact, establishing a physical connection path for the test loop, and ensuring stable transmission of the test signal.

[0065] The contact structure 12 is, for example, a conductor with elasticity or deformation capability, and the first portion 121 and the second portion 122 can be integrally formed or connected after being assembled. In one example, the contact structure 12 is, for example, a conductive rubber column.

[0066] The above embodiment provides a contact structure 12 that achieves fixed connection with the insulation test circuit 14 through the first portion 121 and achieves external contact with the battery housing to be tested through the second portion 122, thereby improving the stability and reliability of the test circuit.

[0067] Figure 4 Another structural diagram of the insulation testing device 10 according to an embodiment of the present application is shown as follows: Figure 4 As shown, the second part 122 includes a conductive rod 1221 , the first part 121 includes a sleeve 1211 , the conductive rod 1221 is sleeved in the sleeve 1211 , and the conductive rod 1221 and the sleeve 1211 are elastically connected via a first elastic member 1222 .

[0068] In this embodiment, the sleeve 1211 is fixed in the connector 11 and can serve as a guide and support base for the conductive rod 1221, constraining the movement trajectory of the conductive rod and preventing deviation.

[0069] The conductive rod 1221 is, for example, a cylindrical metal rod. The conductive rod 1221 and the sleeve 1211 are elastically connected by a first elastic member 1222. The first elastic member 1222 is, for example, a spring. The first elastic member 1222 can provide axial preload. When the connector 11 is plugged into the battery, the first elastic member 1222 is compressed to generate a rebound force, thereby achieving close contact between the contact structure 12 and the shell.

[0070] In this embodiment, when the connector 11 is plugged into the battery, the conductive rod 1221 is squeezed and retracted by the shell, and the first elastic member 1222 is compressed to store energy. The contact tightness between the contact structure 12 and the shell is proportional to the displacement of the conductive rod 1221. Therefore, it is possible to determine whether the contact structure 12 and the battery are loosely connected by detecting the displacement of the conductive rod, thereby improving detection reliability.

[0071] In addition, the combination of the conductive rod 1221 and the sleeve 1211 has the advantages of small size, easy integration and sealing.

[0072] The above embodiment provides a conductive rod and sleeve installation solution to achieve a wire harness-free design, with a virtual connection detection function, and achieve miniaturization and sealing compatibility.

[0073] Figure 5 Another structural diagram of the insulation testing device 10 according to an embodiment of the present application is shown; Figure 5 As shown, the second portion 122 includes a second elastic member 1224, and a protrusion 1225 is provided at the end of the second elastic member 1224 away from the first portion 121. The second elastic member 1224 is connected to the first portion through an elastic actuation lever 1226. The elastic actuation lever 1226 is used to change the angle between the second elastic member 1224 and the horizontal direction so that the protrusion 1225 contacts the battery housing to be tested.

[0074] In this embodiment, the second elastic member 1224 is, for example, a thin sheet of metal with bending elasticity, such as a spring. One end of the second elastic member 1224 is connected to the first portion, and the other end is provided with a protrusion 1225. The protrusion 1225 is, for example, a hemispherical or rectangular metal contact. The direct contact of the protrusion 1225 with the battery casing can concentrate contact pressure, reduce contact resistance, and reduce wear on the battery casing.

[0075] In this embodiment, the elastic actuation lever 1226 refers to a metal lever connecting the first portion and the second elastic member 1224. It can have a built-in torsion spring mechanism. After the connector 11 is plugged into the battery, the displacement of the connector 11 during insertion can be amplified into a change in the angle θ between the second elastic member 1224 (metal sheet) and the horizontal direction, forcing the protrusion to press against the battery housing.

[0076] In this embodiment, when the connector 11 is plugged into the battery, the second elastic member 1224 is squeezed by the housing, and the elastic actuating lever 1226 is forced to rotate around the fulcrum, and the angle θ between the second elastic member 1224 and the horizontal direction decreases. Therefore, it is possible to determine whether the contact structure 12 and the battery are in loose contact by detecting the angle θ, thereby improving detection reliability.

[0077] The above embodiment provides a contact structure 12 solution for rotating contact through an elastic actuation lever 1226, which can realize a wire-free design, has a virtual contact detection function, meets the needs of different scenarios, and improves the flexibility of the contact structure 12.

[0078] In the embodiment of the present application, the portion of the contact structure 12 located outside the connector 11 has an insulating layer or an insulating sleeve.

[0079] For example, when the second portion 122 of the contact structure 12 includes a conductive rod and the first portion 121 includes a sleeve, insulating paint can be sprayed on the outer surface of the exposed portion of the contact structure 12 or an insulating layer can be electroplated, or an insulating sleeve can be provided on the outside of the conductive rod. It should be noted that after the insulating sleeve is provided, the sum of the diameters of the insulating tube and the conductive rod must be less than or equal to the inner diameter of the sleeve so that the conductive rod can be retracted.

[0080] Similarly, when the second portion 122 is the second elastic member 1224 , the outer surfaces of the second elastic member 1224 and the elastic actuating lever 1226 may be sprayed with insulating paint or electroplated with an insulating layer, or an insulating sleeve may be provided.

[0081] In this embodiment, the provision of an insulating layer or insulating sleeve can prevent the operator from being exposed to high-voltage electric shock through physical isolation.

[0082] In the embodiment of the present application, the switch device includes a first switch tube 141 , and the insulation test circuit 14 further includes a first fuse 143 . The first switch tube 141 and the first fuse 143 are connected in series.

[0083] In one example, the first switch tube 141 is a MOS tube, which can quickly respond to the control signal to turn on / off the test circuit. Compared with a mechanical relay, it has the advantages of fast response time and complete disconnection, and has less risk of chain failure caused by mechanical relay failure.

[0084] The first fuse is, for example, a fast-blow fuse, which can be physically melted when there is overcurrent or short circuit, thereby cutting off the high-voltage circuit.

[0085] In this embodiment, the first switch tube 141 and the first fuse are connected in series to form a double insurance mechanism, thereby improving the safety performance of the test circuit.

[0086] In the embodiment of the present application, the switching device includes an electronic switching unit (ESU), in which a second switching tube and a second fuse are integrated. The second switching tube and the second fuse are connected in series.

[0087] This embodiment further integrates the insulation test circuit by integrating an ESU with a second switch tube and a second fuse. On the one hand, it has a double insurance function to improve the safety performance of the test circuit. On the other hand, it is further conducive to the miniaturization and sealing compatibility of the insulation test device 10.

[0088] In an embodiment of the present application, a control end of a switch tube in a switching device is connected to an insulation detection terminal device, and the insulation detection terminal device is used to send a control signal to the switch tube of the switching device.

[0089] The insulation detection terminal device refers to the EOL tester. The insulation detection terminal device sends a control signal to the control end of the switch tube according to the test requirements. The control signal can be a high-level signal or a low-level signal. The high-level signal is used to control the switch tube to be turned on, and the low-level signal is used to control the switch tube to be turned off.

[0090] In this embodiment, the control end of the switch tube is directly connected to the insulation detection terminal device, which can quickly respond to the control signal and improve the test efficiency.

[0091] In the embodiment of the present application, the connector 11 includes a metal area and a non-metal area. The power terminal 13 is arranged in the metal area, and part of the contact structure 12 and the insulation test circuit 14 are arranged in the non-metal area.

[0092] In this embodiment, the metal area supports power supply terminal 13, transmitting the battery's charge and discharge currents—that is, carrying power. The non-metal area provides a low-voltage environment for the contact structure 12 and insulation test circuit 14 signals, achieving physical isolation and improving the anti-interference capability and stability of signal transmission.

[0093] Figure 6 The schematic diagram of the test circuit principle of the embodiment of the present application is shown. Figure 6As shown, after the battery's positive electrode connector 11 is connected to the battery under test, the contact structure 12 contacts the battery housing. The battery housing, positive electrode, switch, test resistor 142, fuse, and contact point form a test circuit. At this point, the EOL tester sends a control signal to the switch, closing it. The BMS in the battery under test can detect the resistance between the positive electrode and the contact point. The battery housing and test resistor 142 are connected in parallel. Based on the principle that two resistors have a lower resistance when connected in parallel, if the measured value is less than the test resistor's value and the measured value is close to the test resistor's value, the insulation performance of the battery under test is determined to be normal. If the difference between the measured value and the test resistor's value is significantly greater, the insulation performance of the battery under test is determined to be abnormal.

[0094] The above embodiment provides an insulation testing device 10, which can achieve high integration of the battery connector 11 and the insulation testing circuit 14, does not require an additional grounding harness, simplifies the topology of the insulation testing system, and can achieve "plug and test" during the testing process, saving the time of connecting the harness, improving the testing efficiency, and realizing the miniaturization and sealing compatibility of the insulation testing device 10.

[0095] This embodiment provides an insulation testing system, which includes a battery to be tested, an insulation testing device 10 and an insulation detection terminal device. The insulation testing device 10 is the insulation testing device 10 described in the above embodiment; the insulation testing device 10 contacts the outer shell of the battery to be tested through a contact structure 12, and the insulation detection terminal device is used to send a control signal to the insulation testing device 10; the charging and discharging ports of the battery to be tested include a positive pole and a negative pole, and the positive pole and the negative pole are both provided with an insulation testing device 10. The battery management unit of the battery to be tested is connected to one end of the insulation testing device 10 of the positive pole through a first relay, and the battery management unit of the battery to be tested is connected to one end of the insulation testing device 10 of the negative pole through a second relay; the other ends of the insulation testing devices 10 of the positive pole and the negative pole are both in contact with the outer shell of the battery to be tested through the contact structure.

[0096] A battery management unit (BMU) is installed in the battery to be tested. The BMU starts the insulation performance test between the battery positive electrode and the housing by controlling the first relay to be turned on and off. The BMU starts the insulation performance test between the battery negative electrode and the housing by controlling the second relay to be turned on and off.

[0097] Specifically, the structure of each insulation testing device 10 and the contact method with the battery housing have been described in the above embodiments, and will not be described again here to avoid repetition.

[0098] The insulation testing system provided in this embodiment can realize comprehensive testing of the insulation performance of the positive and negative electrodes of the battery, and can achieve high integration of the battery connector 11 and the insulation testing circuit 14, without the need for an additional grounding harness, simplifying the topology of the insulation testing system, and realizing "plug and test" during the testing process, saving the time of connecting the harness, improving the testing efficiency, and realizing the miniaturization and sealing compatibility of the insulation testing device 10.

[0099] The present embodiment provides an insulation testing method, which is applied to the above-mentioned insulation testing system, and includes: determining a port to be tested based on the on and off states of a first relay and a second relay, where the port to be tested is the positive electrode or negative electrode of a battery to be tested; obtaining a measurement value between the port to be tested and a contact point, where the contact point is the contact point between the contact structure 12 and the outer shell of the battery to be tested; the measurement value is the total resistance of the insulation resistance and the test resistance in parallel, where the insulation resistance is the resistance between the battery to be tested and the outer shell; if the measurement value is less than the resistance of the test resistance in the insulation test circuit, and the difference between the measurement value and the resistance of the test resistance is less than a preset difference, determining that the insulation performance of the battery to be tested is normal; if the difference between the measurement value and the resistance of the test resistance is greater than the preset difference, determining that the insulation performance of the battery to be tested is abnormal.

[0100] In one example, the on and off states of the first relay and the second relay can be controlled by the battery management unit. When the first relay is on and the second relay is off, the port to be detected is determined to be the positive pole of the battery. When the second relay is on and the first relay is off, the port to be detected is determined to be the negative pole of the battery.

[0101] After the port to be detected is determined, the measurement value between the port to be detected and the contact point is obtained. Specifically, the measurement value can be calculated using the following formula: R measurement value =

[0102] like Figure 6 As shown, the contact point is the contact point between the contact structure 12 and the battery shell to be tested. According to the principle that the resistance value becomes smaller after two resistors are connected in parallel, it can be seen that when the insulation performance of the battery shell to be tested is normal, Infinity, the R measurement value is infinitely close to but less than the R test resistance. The resistance of the test resistor 142 can be set according to actual needs. If the test resistor 142 is 1MΩ, if the R measurement value is <1MΩ, and the measurement value is close to 1MΩ, it means that the insulation performance is normal. If the difference between the R measurement value and the R test resistance is too large, it means that the insulation performance is abnormal.

[0103] The preset difference in this embodiment can be set according to the detection accuracy. The higher the detection accuracy, the smaller the preset difference, and the lower the detection accuracy, the larger the preset difference.

[0104] The insulation testing method provided in this embodiment does not require manual connection of the wiring harness. By monitoring the on and off states of the first relay and the second relay, the interface quickly implements the insulation performance test of the battery, further improving the test efficiency.

[0105] In an embodiment of the present application, when the second part 122 of the contact structure 12 of the insulation testing device 10 includes a conductive rod and the first part 121 includes a sleeve, the method includes: obtaining the expansion and contraction amount of the conductive rod, the expansion and contraction amount including the overlapping length of the second part 122 and the first part 121; when the expansion and contraction amount is greater than or equal to a preset threshold value, determining that the insulation testing device 10 is normally connected to the battery casing to be tested; when the expansion and contraction amount is less than the preset threshold value, determining that the insulation testing device 10 is abnormally connected to the battery casing to be tested.

[0106] The insulation testing device 10 of this embodiment is as follows Figure 4 As shown, when the connector 11 is plugged into the battery, the conductive rod is squeezed and retracted by the shell, and the first elastic member is compressed to store energy. The contact tightness between the contact structure 12 and the shell is proportional to the displacement of the conductive rod. Therefore, the displacement of the conductive rod can be detected to determine whether the contact structure 12 and the battery are loosely connected, thereby improving detection reliability.

[0107] Specifically, the extension and contraction amount of the conductive rod can be obtained by detecting the axial displacement of the conductive rod relative to the sleeve through a displacement sensor (such as a Hall sensor or a linear encoder) integrated inside the connector 11, and the preset threshold can be set according to actual accuracy requirements.

[0108] When the expansion and contraction amount is greater than or equal to the preset threshold value, it means that the conductive rod is squeezed and retracted by the shell, and the conductive rod is in close contact with the shell, and it is determined that the connection between the insulation testing device 10 and the battery shell to be tested is normal; when the expansion and contraction amount is less than the preset threshold value, the contact between the conductive rod and the shell is loose, and it is determined that the connection between the insulation testing device 10 and the battery shell to be tested is abnormal.

[0109] This embodiment can accurately and quickly determine whether there is a loose connection between the contact structure 12 and the battery according to the expansion and contraction amount of the conductive rod.

[0110] In an embodiment of the present application, when the second portion 122 of the contact structure 12 of the insulation testing device 10 is a second elastic member 1224, the method further includes: obtaining the angle between the second elastic member and the horizontal direction; when the angle is within a preset angle range, determining that the insulation testing device 10 is normally connected to the battery casing to be tested; when the angle exceeds the preset angle range, determining that the insulation testing device 10 is abnormally connected to the battery casing to be tested.

[0111] The insulation testing device 10 of this embodiment is as follows Figure 5As shown, when the connector 11 is plugged into the battery, the second elastic member is squeezed by the housing, and the elastic actuating lever 1226 is forced to rotate around the fulcrum, and the angle θ between the second elastic member and the horizontal direction is reduced. Therefore, it is possible to determine whether the contact structure 12 and the battery are in loose contact by detecting the angle θ, thereby improving detection reliability.

[0112] In one example, the angle θ can be obtained by an angle sensor or photoelectric encoder integrated in the elastic actuation lever. The preset angle range is determined based on the initial angle. Assuming that the initial value of the angle θ between the second elastic member and the horizontal direction is 120° before the connector 11 is connected to the battery, the angle θ will decrease after insertion. The preset angle range is, for example, 118° to 100°, where 100° is the lower limit of the preset angle. If θ is less than 100°, there is a possibility that the second elastic member is damaged. In this embodiment, when the angle is within the preset angle range, it is determined that the insulation test device 10 is normally connected to the battery housing to be tested. When the angle exceeds the preset angle range, it is determined that the insulation test device 10 is abnormally connected to the battery housing to be tested, which can improve the reliability of system insulation detection.

[0113] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0114] The insulation testing method provided in the above-mentioned embodiment of the present application and the insulation testing device provided in the embodiment of the present application are based on the same application concept and have the same beneficial effects.

[0115] It should be noted that: In the above text, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0116] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a more preferred embodiment. Based on this understanding, the technical solution of this application, or the part that contributes to the existing technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of this application.

[0117] The embodiments of the present application are described above in conjunction with the accompanying drawings, which are only specific implementation methods of the present application. However, the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. An insulation testing device, characterized in that: The device comprises: a connector and a contact structure, The connector is connected to the contact structure, and the contact structure is used to contact the outer shell of the battery to be tested; a power supply terminal is provided in the connector, and the power supply terminal is used to connect to the charging and discharging port of the battery to be tested; An insulation test circuit is provided inside the connector, one end of the insulation test circuit is electrically connected to the contact structure, and the other end of the insulation test circuit is connected to the power supply end; The insulation test circuit includes a switch device and a test resistor arranged in series. The control end of the switch device is used to receive a control signal sent by an insulation detection terminal device, and the switch device is configured to control the conduction or shutdown of the insulation test circuit according to the control signal. The insulation test circuit is configured to determine the insulation performance of the battery to be tested based on a comparison result of the resistance value of the test resistor and a measured value. The measured value is the total resistance of the insulation resistance and the test resistor in parallel. The insulation resistance is the resistance between the battery to be tested and the casing.

2. The insulation testing device according to claim 1, characterized in that: The contact structure includes a first portion and a second portion, wherein the first portion is electrically connected to one end of the insulation test circuit and fixedly connected to the connector, and the second portion extends to the outside of the connector, and the end of the second portion facing away from the first portion is used to contact the battery housing to be tested.

3. The insulation testing device according to claim 2, characterized in that: The second portion includes a conductive rod, the first portion includes a sleeve, the conductive rod is sleeved in the sleeve, and the conductive rod and the sleeve are elastically connected via a first elastic member.

4. The insulation testing device according to claim 2, characterized in that: The second part includes a second elastic member, and a protrusion is provided at the end of the second elastic member facing away from the first part. The second elastic member is connected to the first part through an elastic actuation lever, and the elastic actuation lever is used to change the angle between the second elastic member and the horizontal direction so that the protrusion contacts the battery casing to be tested.

5. The insulation testing device according to any one of claims 2 to 4, characterized in that: The portion of the contact structure located outside the connector has an insulating layer or an insulating sleeve.

6. The insulation testing device according to claim 1, characterized in that: The switching device includes a first switching tube, and the insulation test circuit also includes a first fuse. The first switching tube and the first fuse are connected in series.

7. The insulation testing device according to claim 1, characterized in that: The switch device includes an electronic switch unit, in which a second switch tube and a second fuse are integrated. The second switch tube and the second fuse are connected in series.

8. The insulation testing device according to any one of claims 1-4, 6-7, characterized in that: The connector includes a metal area and a non-metal area, the power supply terminal is arranged in the metal area, and the contact structure portion and the insulation test circuit are arranged in the non-metal area.

9. An insulation testing system, characterized in that: The system includes a battery to be tested, an insulation testing device and an insulation detection terminal device, wherein the insulation testing device is the insulation testing device according to any one of claims 1 to 8; The insulation testing device contacts the battery housing to be tested through the contact structure, and the insulation detection terminal device is used to send a control signal to the insulation testing device; The charging and discharging ports of the battery to be tested include a positive electrode and a negative electrode, and the positive electrode and the negative electrode are both provided with the insulation testing device. The battery management unit of the battery to be tested is connected to one end of the insulation testing device of the positive electrode through a first relay, and the battery management unit of the battery to be tested is connected to one end of the insulation testing device of the negative electrode through a second relay; the other ends of the insulation testing devices of the positive electrode and the negative electrode are in contact with the outer shell of the battery to be tested through a contact structure.

10. An insulation testing method, characterized in that: The method is applied to the insulation testing system according to claim 9, and the method comprises: Determine a port to be detected according to the on and off states of the first relay and the second relay, where the port to be detected is the positive electrode or the negative electrode of the battery to be tested; Obtaining a measurement value between the port to be tested and a contact point, wherein the contact point is the contact point between the contact structure and the housing of the battery to be tested; the measurement value is the total resistance of the insulation resistance and the test resistor in parallel, wherein the insulation resistance is the resistance between the battery to be tested and the housing; When the measured value is smaller than the resistance of the test resistor in the insulation test circuit, and the difference between the measured value and the resistance of the test resistor is smaller than a preset difference, determining that the insulation performance of the battery to be tested is normal; When the difference between the measured value and the resistance value of the test resistor is greater than the preset difference, it is determined that the insulation performance of the battery to be tested is abnormal.

11. The insulation testing method according to claim 10, characterized in that: In a case where the second portion of the contact structure of the insulation testing device includes a conductive rod and the first portion includes a bushing, the method further includes: Acquiring an extension and contraction amount of the conductive rod, wherein the extension and contraction amount includes an overlapping length of the second portion and the first portion; When the expansion and contraction amount is greater than or equal to a preset threshold, determining that the insulation testing device is normally connected to the battery housing to be tested; When the expansion and contraction amount is less than the preset threshold, it is determined that the connection between the insulation testing device and the battery casing to be tested is abnormal.

12. The insulation testing method according to claim 10, characterized in that: In a case where the second portion of the contact structure of the insulation testing device is a second elastic member, the method further includes: Obtaining an angle between the second elastic member and the horizontal direction; When the included angle is within a preset angle range, determining that the insulation testing device is normally connected to the battery housing to be tested; When the included angle exceeds the preset angle range, it is determined that the connection between the insulation testing device and the battery casing to be tested is abnormal.

Images