Detection circuit and method of fast charging contactor, BMS, battery pack and electric energy equipment

Abstract

The invention provides a detection circuit and method of a fast charging contactor, a BMS, a battery pack and an electric energy device, and a control module in the detection circuit can determine whether the fast charging contactor is adhered or not based on a characteristic voltage collected by a pre-charging voltage in a process of pre-charging a main loop before the main loop of a battery is conducted. Therefore, a special detection time sequence does not need to be set for the detection of the fast-charging contactor, the power-on time sequence of the battery and the fast-charging contactor is not influenced, the detection speed is higher, and whether the fast-charging contactor is adhered or not can be detected more quickly and effectively.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a detection circuit and method for a fast charging contactor, a battery management system (BMS), a battery pack, and an electric energy device. Background Art

[0002] With the continuous development of automobile technology and battery technology, more and more batteries on cars support DC fast charging function. When the battery is connected to a DC charging pile, the DC charging pile can quickly charge the battery of the car by providing DC power. Since the charging current provided by the DC charging pile to the battery is large in current and power, the BMS needs to monitor the status of the fast charging contactor in real time. If a collision or other unexpected events occur during the charging process, the BMS needs to control the fast charging contactor to disconnect in time. Therefore, the BMS also needs to detect whether the fast charging contactor is stuck to prevent the fast charging contactor from not being disconnected in time due to adhesion, which may lead to more serious safety problems. However, the detection method of whether the fast charging contactor is stuck by the BMS in the existing technology relies on a specially designed detection sequence, which affects the normal charging process of the battery. Summary of the Invention

[0003] The present application provides a fast charging contactor detection circuit, method, BMS, battery pack and electric energy equipment, so as to more quickly and effectively detect whether the fast charging contactor is stuck during the charging process without affecting the normal charging sequence of the battery.

[0004] In a first aspect, the present application provides a detection circuit for a fast-charging contactor, comprising: a voltage acquisition module for acquiring a characteristic voltage of a fast-charging contactor arranged on a fast-charging circuit of a battery; a pre-charging module for pre-charging the main circuit of the battery; and a control module, respectively connected to the voltage acquisition module and the control module, for controlling the pre-charging module to pre-charge the main circuit of the battery before the main circuit is turned on, and determining whether the fast-charging contactor is stuck based on the characteristic voltage acquired by the voltage acquisition module when the main circuit is in the pre-charging state.

[0005] A second aspect of the present application provides a method for detecting a fast-charging contactor, which is applied to a detection circuit of the fast-charging contactor. The detection circuit of the fast-charging contactor includes: a voltage acquisition module for acquiring a characteristic voltage of a fast-charging contactor arranged on a fast-charging circuit of a battery; a pre-charging module for pre-charging the main circuit of the battery; the detection method includes: before the main circuit is turned on, controlling the pre-charging module to pre-charge the main circuit of the battery; when the main circuit is in a pre-charging state, determining whether the fast-charging contactor is stuck based on the characteristic voltage acquired by the voltage acquisition module.

[0006] A third aspect of the present application provides a BMS, comprising a adhesion detection circuit for the fast charging contactor as described in the first aspect of the present application.

[0007] A fourth aspect of the present application provides a battery pack, comprising the BMS as described in the third aspect of the present application.

[0008] The fifth aspect of the present application provides an electric energy device, comprising the battery pack provided in the fourth aspect of the present application.

[0009] In summary, the present application provides a detection circuit, method, BMS, battery pack and electric energy equipment for a fast charging contactor, wherein the control module in the detection circuit can determine whether the fast charging contactor is stuck based on the characteristic voltage obtained by pre-charging the main circuit before the main circuit of the battery is turned on, thereby eliminating the need to set a special detection timing for the detection of the fast charging contactor, and will not affect the power-on timing of the battery and the fast charging contactor. It also has a faster detection speed, and can detect whether the fast charging contactor is stuck more quickly and effectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0011] Figure 1 A schematic diagram of the application scenario of this application;

[0012] Figure 2 1. A schematic diagram of the structure of a battery pack;

[0013] Figure 3 This is a structural diagram of an embodiment of a detection circuit for a fast charging contactor provided by the present application;

[0014] Figure 4 A schematic flow chart of an embodiment of a method for detecting a fast-charging contactor provided in this application;

[0015] Figure 5 A schematic diagram of the circuit structure of an embodiment of a detection circuit for a fast charging contactor provided in this application;

[0016] Figure 6 A schematic diagram of a process for determining whether a fast-charging negative contactor is stuck provided in this application;

[0017] Figure 7 A schematic diagram of the first process for determining whether a fast-charging positive contactor is stuck provided in this application;

[0018] Figure 8 A schematic diagram of the second process for determining whether a fast-charging positive contactor is stuck provided in this application;

[0019] Figure 9 A schematic flow chart of an embodiment of a method for detecting a fast-charging contactor provided in this application;

[0020] Figure 10 A schematic flow chart of an embodiment of a method for detecting a fast-charging contactor provided in this application;

[0021] Figure 11 A schematic flow chart of an embodiment of a method for detecting a fast-charging contactor provided in this application;

[0022] Figure 12 A schematic flow chart of an embodiment of a method for detecting a fast-charging contactor provided in this application;

[0023] Figure 13 This is a schematic diagram of the structure of an electronic device provided in this application.

[0024] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0026] The terms "first," "second," "third," "fourth," and the like (if any) in the specification and claims of this application and in the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0027] Figure 1 This is a schematic diagram of the application scenario of this application, such as Figure 1As shown, the present application is applied in the DC fast charging scenario of batteries. For example, with the continuous development of automobile technology and battery technology, more and more batteries on cars support DC fast charging function. Then, when the charging head of the electric vehicle is connected to the charging interface of the DC charging pile, the battery pack 1 of the electric vehicle is connected to the fast charging device 2 through the DC positive pole DC+ and the DC negative pole DC-. The fast charging device 2 can be used to provide DC power to the battery pack 1, thereby directly providing DC power to the battery pack 1, and charging the battery pack 1 more quickly.

[0028] Figure 2 A schematic diagram of the structure of a battery pack is shown. Figure 1 A specific implementation of the battery pack 1. Figure 2 The battery pack 1 shown includes: a battery 10 and a BMS 11, wherein the BMS 11 can be used to control the charge and discharge of the battery 10. Specifically, Figure 2 The BMS 11 shown includes: a control module 110 , a main positive contactor KM1 , a main negative contactor KM2 , a fast charging positive contactor KM3 , and a fast charging negative contactor KM4 .

[0029] The positive electrode of battery 10 is connected to the positive DC bus Link+ of the electric vehicle's load via a main positive contactor KM1, and the negative electrode of battery 10 is connected to the negative DC bus Link- of the electric vehicle's load via a main negative contactor KM2. When control module 110 controls main positive contactor KM1 and main negative contactor KM2 to conduct, battery 10 can be used to supply power to the load via the positive DC bus and the negative DC bus.

[0030] The positive electrode of the battery 10 is also connected to the fast-charging positive electrode DC+ of the fast-charging device 2 through the main positive contactor KM1 and the fast-charging positive contactor KM3. The negative electrode of the battery 10 is also connected to the fast-charging negative electrode DC- of the fast-charging device 2 through the main negative contactor KM2 and the fast-charging negative contactor KM4. When the control module 110 controls the main positive contactor KM1, the main negative contactor KM2, the fast-charging positive contactor KM3, and the fast-charging negative contactor KM4 to conduct, the fast-charging device 2 can be used to charge the battery 10 through the fast-charging positive electrode DC+ and the fast-charging negative electrode DC-.

[0031] As well as Figure 2The illustrated battery pack 1 also includes a pre-charge module 112, which includes a 12V power supply and a DC-DC converter. After the battery pack 1 is connected to the fast-charging device 2 and before the fast-charging device 2 starts charging the battery 10, the control module 110 controls either the main positive contactor KM1 or the main negative contactor KM2 to conduct, charging the DC positive bus Link+ or the DC negative bus Link-. This prevents the charging voltage provided by the fast-charging device 2 from exceeding the voltage of the DC bus connected to the battery 10. This would cause a voltage differential between the main positive contactor KM1 and the main negative contactor KM2 when the battery 10 is turned on, potentially leading to more serious safety issues. Subsequently, after the DC positive bus Link+ or the DC negative bus Link- has been charged to a certain voltage, the control module 110 controls the main positive contactor KM1, the main negative contactor KM2, the fast-charging positive contactor KM3, and the fast-charging negative contactor KM4 to conduct, allowing the fast-charging device 2 to begin charging the battery 10.

[0032] Furthermore, since the charging current provided by the charging device 2 to the battery 10 has a large current and power, the control module 110 in the BMS11 also needs to monitor the status of the fast charging contactor in real time. If a collision or other unexpected events occur during the charging process, the BMS11 needs to promptly control the fast charging contactor to disconnect to ensure the safety of the battery 10 and the equipment in which it is located.

[0033] In order to ensure that the fast-charging contactor can be disconnected in time when it needs to be disconnected, the BMS also needs to detect whether the fast-charging contactor is stuck. How to make the BMS detect whether the fast-charging contactor is stuck more quickly and effectively is a technical problem that needs to be solved in this application. The technical solution of this application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0034] Figure 3 This is a structural diagram of an embodiment of a detection circuit for a fast charging contactor provided in this application, as shown in FIG. Figure 3 The detection circuit shown can be applied to Figure 1 and Figure 2 In the scenario shown, specifically, Figure 3 The detection circuit of the fast charging contactor shown includes: a control module 110, a pre-charging module 112 and a control module 113, and the control module 110 is connected to the pre-charging module 112 and the voltage acquisition module 113 respectively.

[0035] The pre-charge module 112 can be used to pre-charge the main circuit of the battery 10 before the battery 10 starts charging, and the voltage acquisition module 113 can be used to collect the characteristic voltage of the fast-charging contactor provided on the fast-charging circuit of the battery 10 and send the characteristic voltage to the control module 110. The control module 110 can be used to control the pre-charge module 112 and determine whether the fast-charging contactor is stuck based on the characteristic voltage obtained by the voltage acquisition module 113.

[0036] Specifically, Figure 4 This is a flow chart of an embodiment of a method for detecting a fast charging contactor provided by the present application, as shown in FIG. Figure 4 The method shown can be applied Figure 3 The detection circuit of the fast charging contactor shown in FIG. 1 is executed by the control module 110. Specifically, Figure 4 The detection method of the fast charging contactor shown includes:

[0037] S101 : Before the main circuit of the battery 10 is turned on, the control module 110 controls the pre-charging module 112 to pre-charge the main circuit of the battery 10 .

[0038] In one embodiment, after the battery pack 1 is connected to the fast charging device 2 and before the fast charging device 2 is controlled to charge the battery 10, the control module 110 controls the pre-charging module 112 to pre-charge the main circuit of the battery 10, specifically by controlling the main positive contactor KM1 to turn on and simultaneously controlling the main negative contactor KM2 to turn off, and charging the DC positive bus Link+ through the main positive contactor KM1.

[0039] In another embodiment, after the battery pack 1 is connected to the fast charging device 2 and before the fast charging device 2 is controlled to charge the battery 10, the control module 110 controls the pre-charging module 112 to pre-charge the main circuit of the battery 10, specifically by controlling the main positive contactor KM1 to disconnect and simultaneously controlling the main negative contactor KM2 to turn on, and charging the DC negative bus Link- through the main negative contactor KM2.

[0040] S102: When the pre-charging module 112 pre-charges the main circuit of the battery 10 to put the main circuit in a pre-charging state, the control module 110 obtains the characteristic voltage collected by the voltage collection module 113 and determines whether the fast charging contactor is stuck based on the characteristic voltage.

[0041] It can be seen that the control module 110 provided in this embodiment can determine whether the fast charging contactor is stuck based on the characteristic voltage obtained by pre-charging the main circuit before the main circuit of the battery 10 is turned on, thereby eliminating the need to set a special detection sequence for the detection of the fast charging contactor, and will not affect the power-on sequence of the battery 10 and the fast charging contactor. It also has a faster detection speed and can detect whether the fast charging contactor is stuck more quickly and effectively. In the specific implementation process, sintering detection and other detection and processing can be completed more quickly before the fast charging contactor is closed.

[0042] More specifically, the control module 110 provided in this embodiment can determine whether the fast charging positive contactor KM3 and the fast charging negative contactor KM4 are adhered based on the characteristic voltage collected by the voltage acquisition module. Among them, the control module 110 can first determine whether the fast charging negative contactor KM4 is adhered based on the characteristic voltage collected by the voltage acquisition module 113. Among them, the fast charging negative contactor KM4 is closed when it is adhered, and is not closed when it is not adhered. And, the fast charging negative contactor KM4 can also be controlled to be in a closed state. Subsequently, based on the two different situations in which the fast charging negative contactor KM4 is determined to be closed and not closed, it is further determined whether the fast charging positive contactor KM3 is adhered based on the characteristic voltage collected by the voltage acquisition module 113. The embodiment of the present application is closer to the specific implementation of the solution by separately judging whether the fast charging positive contactor KM3 and the fast charging negative contactor KM4 are adhered, and can provide a more effective fast charging contactor detection method.

[0043] In one embodiment, the voltage acquisition module 113 specifically includes: a first acquisition unit, a second acquisition unit, and a third acquisition unit. The first acquisition unit is used to acquire a first characteristic voltage corresponding to the fast-charging negative contactor KM4, the second acquisition unit is used to acquire a second characteristic voltage and a third characteristic voltage corresponding to the fast-charging positive contactor KM3, and the third acquisition unit is used to acquire a fourth characteristic voltage corresponding to the fast-charging positive contactor KM3.

[0044] For the control module 110, it can be determined whether the fast charging negative contactor KM4 is adhered based on the first characteristic voltage. And, when it is determined that the fast charging negative contactor is closed, it is determined whether the fast charging positive contactor KM3 is adhered based on the second characteristic voltage and the third characteristic voltage. And when the fast charging negative contactor KM4 is not closed, it is determined whether the fast charging positive contactor KM3 is adhered based on the fourth characteristic voltage. It can be seen that in the detection method of the fast charging contactor provided in this embodiment, the control module 110 only needs to detect whether the fast charging contactor is adhered based on the characteristic voltage. Its control logic is relatively simple, easy to implement and operate, and more conducive to the application and promotion of the embodiments of the present application.

[0045] Figure 5 This is a circuit diagram of an embodiment of a detection circuit for a fast charging contactor provided in this application, as shown in FIG. Figure 5 The figure shows a specific circuit implementation of the voltage acquisition module 113 in the detection circuit of the fast charging contactor provided by the present application, such as Figure 5 As shown, in the voltage acquisition module 113 provided in this embodiment:

[0046] The first acquisition unit includes: a first voltage divider component R3, a second voltage divider component R4 and a first diode D3, wherein the first end of the first voltage divider component R3 is connected to the voltage source, the second end of the first voltage divider component R3 is connected to the first end of the second voltage divider component R3, the second end of the second voltage divider component R3 is connected to the positive electrode of the first diode D3, and the negative electrode of the first diode D3 is grounded through the fast charging negative electrode contactor KM4. The voltage source can be a 2.5V voltage source, which can be implemented using the existing voltage source in the BMS.

[0047] The second acquisition unit includes: a first switch S1, a second switch S2, a third voltage divider component R1 and a fourth voltage divider component R2, wherein the first end of the first switch is connected between the fast charging positive contactor KM3 and the fast charging positive interface corresponding to the fast charging positive pole DC+, the second end of the first switch S1 is connected to the first end of the third voltage divider component R1, the second end of the third voltage divider component R1 is connected to the first end of the fourth voltage divider component R2, the second end of the fourth voltage divider component R4 is connected between the fast charging negative contactor KM4 and the fast charging negative interface corresponding to the fast charging negative pole DC-, the first end of the second switch S2 is connected to one end of the main positive contactor KM1, and the second end of the second switch S2 is connected to one end of the main negative contactor KM2.

[0048] The third acquisition unit includes: a third switch S3, a second diode D1 and a third diode D2, wherein the anode of the second diode D1 is connected to the first end of the first voltage divider component R3 and the voltage source, the cathode of the second diode D2 is connected to the second end of the first voltage divider component R3, the first end of the second voltage divider component R4 and the anode of the third diode D2, the cathode of the third diode D2 is connected to the first end of the third switch S3, and the second end of the third switch S3 is connected to the second end of the fourth voltage divider component R2.

[0049] In one embodiment, Figure 5 The first switch S1 , the second switch S2 , and the third switch S3 shown are all optocoupler switches.

[0050] In one embodiment, if Figure 5 The first voltage dividing component R3 , the second voltage dividing component R4 , the third voltage dividing component R1 and the fourth voltage dividing component R2 are all one or more voltage dividing resistors.

[0051] In one embodiment, if Figure 5In the detection circuit of the fast charging contactor shown, the voltage acquisition module 113 also includes:

[0052] The first voltage detection module is connected between the first voltage dividing component R3 and the second voltage dividing component R4 and is connected to the control module 113 , and can be used to detect the voltage at point A and send it to the control module.

[0053] The second voltage detection module is connected between the third voltage dividing component R1 and the fourth voltage dividing component R2 and is connected to the control module 113 , and can be used to detect the voltage at point B and send the result to the control module 113 .

[0054] The third voltage detection module is connected between the second switch S2 and the main negative contactor KM2 and is connected to the control module 113 , and can be used to detect the voltage at point C and send it to the control module 113 .

[0055] This application does not limit the specific implementation of the above voltage detection module, and the above voltage detection module is not Figure 5 Shown in.

[0056] It can be seen that Figure 5 The detection circuit of the fast charging contactor shown is implemented by components such as resistors and diodes, and the characteristic voltage corresponding to the fast charging contactor is detected by the voltage divider principle, so that the control module 113 can detect the fast charging contactor based on the characteristic voltage. The detection circuit provided by this embodiment has a simple circuit structure and simple circuit implementation, which makes the cost of the detection circuit lower and is more conducive to the practical application of the detection circuit.

[0057] The following describes, in conjunction with the accompanying drawings, a method in which the control module 113 according to an embodiment of the present application determines whether the fast charging contactor is stuck based on the characteristic voltage of the voltage acquisition module.

[0058] Figure 6 The present application provides a flow chart of determining whether the fast charging negative contactor is stuck, showing a method in which the control module 113 determines whether the fast charging negative contactor KM4 is stuck according to the first characteristic voltage. Figure 6 As shown, the control module 113 first obtains the first characteristic voltage V2-1 between the first voltage divider component R3 and the second voltage divider component R4 collected by the voltage acquisition module 113. Subsequently, the control module 113 determines whether the fast charging negative contactor KM4 is stuck based on the first characteristic voltage V2-1.

[0059] When the first characteristic voltage V2-1 is within the first preset range, it is determined that the fast charging negative contactor KM4 is adhered. Figure 5In the circuit diagram, when the fast charging negative contactor KM4 is adhered, it is in a closed state of conduction. Assume that the voltage source injects a voltage of 2.5V. At this time, the first characteristic voltage V2-1 at point A is 2.5V based on the voltage dividing value of the first voltage dividing component R3 and the second voltage dividing component R4. For example, assuming that the resistance value of the first voltage dividing component R3 and the second voltage dividing component R4 is the same, the first preset range can be set to 1.24V-1.26V, etc.

[0060] When the first characteristic voltage V2-1 is within the second preset range, it is determined that the fast charging negative electrode contactor KM4 is not adhered. Figure 5 In the circuit diagram, when the fast-charging negative contactor KM4 is not adhered and is in a disconnected, unclosed state, assuming that the voltage source injects a voltage of 2.5V, the first characteristic voltage V2-1 at point A is close to the full-scale voltage value of 2.5V. The second preset range can be set to 2.49V-2.51V, etc. It can be understood that there is no overlap between the second preset range and the first preset range.

[0061] When the first characteristic voltage V2-1 is within the third preset range, it is determined that the first acquisition unit is abnormal, the currently acquired first characteristic voltage V2-1 is invalid, and whether the fast charging negative contactor KM4 is adhered is determined based on the first characteristic voltage V2-1. In this embodiment, by judging whether the first characteristic voltage V2-1 is valid, the accuracy and effectiveness of the result of whether the fast charging negative contactor KM4 is adhered are further ensured. It can be understood that the third preset range does not overlap with the first preset range and the second preset range. For example, assuming that the voltage source injects a voltage of 2.5V, the third preset range can be set to be less than 0V or greater than 5V, etc.

[0062] Figure 7 The first flow chart provided in this application for determining whether the fast-charging positive contactor is stuck shows that when it is determined that the fast-charging negative contactor KM4 is stuck, the fast-charging negative contactor KM4 is in a closed state of conduction, and the control module 113 determines whether the fast-charging positive contactor is stuck based on the second characteristic voltage and the third characteristic voltage.

[0063] like Figure 7 As shown, when the control module 113 passes Figure 6According to the method shown, after determining that the fast-charging negative contactor K3 is in a stuck state, the control module 113 controls the first switch S1 and the second switch S2 to be turned on, thereby obtaining the second characteristic voltage V1 at point C on both sides of the second switch S2 collected by the voltage acquisition module 113, and the third characteristic voltage V3 at point B between the third voltage divider component R1 and the fourth voltage divider component R2. Subsequently, the control module 113 determines whether the fast-charging positive contactor KM3 is stuck based on the second characteristic voltage V1 and the third characteristic voltage V3.

[0064] Among them, when the difference between the second characteristic voltage V1 and the third characteristic voltage V3 is within the fourth preset range, it is determined that the fast charging positive contactor KM3 is stuck. Or, when the change rate Vv3 of the third characteristic voltage V3 is within the fifth preset range, it is determined that the fast charging positive contactor KM3 is stuck. Figure 5 In the circuit diagram, the fast-charging negative contactor KM4 is not adhered and is in a disconnected, unclosed state. If the fast-charging positive contactor KM3 is adhered and in a conductive state at this time, then since the pre-charging module 112 pre-charges the main circuit at this time, the DC positive bus Link+ passes through the fast-charging positive contactor KM3, causing the third characteristic voltage V3 at point B to gradually increase. Moreover, since the fast-charging positive contactor KM3 is adhered and in a conductive state, the voltage values ​​between the second characteristic voltage V1 and the third characteristic voltage V3 on both sides thereof are closer. Therefore, the state of the fast-charging positive contactor KM3 can be determined by setting the difference between the second characteristic voltage V1 and the third characteristic voltage V3, or the preset range of the change rate Vv3 of the third characteristic voltage V3. In one embodiment, the fourth preset range can be set to: the absolute value of the difference between the second characteristic voltage V1 and the third characteristic voltage V3 is less than or equal to 20V. In one embodiment, the fifth preset range can be set to the change rate Vv3 of the third characteristic voltage V3 between [1V / ms, 1.6V / ms].

[0065] When the difference between the second characteristic voltage V1 and the third characteristic voltage V3 is within the sixth preset range, it is determined that the fast charging positive contactor KM3 is not stuck. Alternatively, when the rate of change Vv3 of the third characteristic voltage V3 is within the seventh preset range, it is determined that the fast charging positive contactor KM3 is not stuck. Figure 5In the circuit diagram, the fast charging negative contactor KM4 is not adhered and is in a disconnected, unclosed state. If the fast charging positive contactor KM3 is not adhered and is in a disconnected state at this time, then because the pre-charging module 112 pre-charges the main circuit at this time, the voltage value difference between the second characteristic voltage V1 and the third characteristic voltage V3 on both sides is larger, and the third characteristic voltage V3 at the position of point B will not change. Therefore, in one embodiment, the sixth preset range can be set to the absolute value of the difference between the second characteristic voltage V1 and the third characteristic voltage V3 is greater than 20V. In one embodiment, the seventh preset range can be set to the change rate Vv3 of the third characteristic voltage V3 is not between [1V / ms, 1.6V / ms], for example, between [0V / ms, 1V / ms].

[0066] When the second characteristic voltage V1 is within the eighth preset range, or the third characteristic voltage V3 is within the ninth preset range, it is determined that the second acquisition unit is abnormal, the currently acquired second characteristic voltage V1 and the third characteristic voltage V3 are invalid, and whether the fast charging positive contactor KM3 is adhered is determined based on the second characteristic voltage V1 and the third characteristic voltage V3. In this embodiment, by judging whether the second characteristic voltage V1 and the third characteristic voltage V3 are valid, the accuracy and effectiveness of the result of whether the fast charging positive contactor KM3 is adhered is further ensured. For example, the eighth preset range can be set to be greater than 100V, the ninth preset range can be set to be greater than 50V, etc.

[0067] Figure 8 The second flow chart provided in this application for determining whether the fast-charging positive contactor is stuck shows that when it is determined that the fast-charging negative contactor KM4 is not stuck, and the fast-charging negative contactor KM4 is in a disconnected, unclosed state, the control module 113 determines whether the fast-charging positive contactor KM3 is stuck based on the fourth characteristic voltage.

[0068] like Figure 8 As shown, when the control module 113 passes Figure 6 According to the method shown, after determining that the fast charging negative contactor K3 is in a non-adhesive state, the control module 113 controls the first switch S1 and the third switch S3 to be turned on, thereby obtaining the first characteristic voltage V2-2 at point A between the first voltage divider component R3 and the second voltage divider component R4 collected by the voltage acquisition module 113. Subsequently, the control module 113 determines whether the fast charging positive contactor KM3 is adhered based on the fourth characteristic voltage V2-2.

[0069] When the fourth characteristic voltage V2-2 is within the tenth preset range, it is determined that the fast charging positive contactor KM3 is adhered. Figure 5In the circuit diagram, when the fast-charging negative contactor KM4 is adhered and in a closed state, and the fast-charging positive contactor KM3 is also adhered and in a conductive state, the current direction in the circuit is: DC positive bus Link+, fast-charging positive contactor KM3, the first switch S1, the third voltage divider component R1, the fourth voltage divider component R2, the third switch S3, the third diode D2, the second voltage divider component R4, the first diode D3 and the DC negative bus Link-. At this time, the first characteristic voltage V2-2 at point A between the first voltage divider component R3 and the second voltage divider component R4 is the voltage divided value of the voltage provided by the voltage source on the third diode D2. For example, assuming that the voltage source injects a voltage of 2.5V, the tenth preset range can be set to a range near -0.7V, such as a range between -0.69 and -0.71.

[0070] When the fourth characteristic voltage V2-2 is within the eleventh preset range, it is determined that the fast charging positive contactor KM3 is not stuck. Figure 5 In the circuit diagram, when the fast-charging positive contactor KM3 is not adhered and is in a disconnected state, there is no current passing through the fast-charging positive contactor KM3. Assuming that the voltage source injects a voltage of 2.5V, the fourth characteristic voltage V2-2 at point A is close to the full-scale voltage value of 2.5V. The second preset range can be set to 2.49V-2.51V, etc. It can be understood that there is no overlap between the second preset range and the first preset range.

[0071] When the fourth characteristic voltage V2-2 is within the twelfth preset range, it is determined that the third acquisition unit is abnormal, the currently acquired fourth characteristic voltage V2-2 is invalid, and the determination of whether the fast-charging positive contactor KM3 is adhered based on the fourth characteristic voltage V2-2 is also invalid. Among them, this embodiment further ensures the accuracy and effectiveness of the result of whether the fast-charging positive contactor KM3 is adhered by judging whether the fourth characteristic voltage V2-2 is valid. It can be understood that the twelfth preset range does not overlap with the tenth preset range and the eleventh preset range. For example, assuming that the voltage source injects a voltage of 2.5V, the twelfth preset range can be set to be less than 0V or greater than 5V, etc.

[0072] Figure 9 A flow chart of an embodiment of a method for detecting a fast charging contactor provided in this application shows Figure 6The embodiment shown is a specific implementation method. Among them, after the control module 113 starts the process, after receiving the command sent by other controllers to detect the state of the fast charging negative contactor KM4, it obtains the first characteristic voltage V2-1 between the first voltage divider component R3 and the second voltage divider component R4 collected by the voltage acquisition module 113, and judges the validity of the first characteristic voltage V2-1 based on whether the first characteristic voltage V2-1 is within the third preset range. If the first characteristic voltage V2-1 is not within the third preset range, the first characteristic voltage V2-1 is valid, and it is further judged whether the first characteristic voltage V2-1 is between the first preset range of 1.0V-1.7V. If so, it is determined that the fast charging negative contactor KM4 is in a closed adhesion state. If not, it is determined that the fast charging negative contactor KM4 is in a disconnected non-adhesion state. If the first characteristic voltage V2-1 is within the third preset range, the first characteristic voltage V2-1 is invalid, and the state of the fast charging negative contactor KM4 is determined to be invalid.

[0073] Figure 10 A flow chart of an embodiment of a method for detecting a fast charging contactor provided in this application shows Figure 7 A specific implementation of the embodiment shown. Among them, after the control module 113 starts the process, it detects that the fast charging negative contactor KM4 is in a closed state, and then obtains the second characteristic voltage V1 at the C point on both sides of the second switch S2 collected by the voltage acquisition module 113, and the third characteristic voltage V3 at the B point between the third voltage divider component R1 and the fourth voltage divider component R2. And based on the eighth preset range, it is judged whether the second characteristic voltage V1 is within the normal range, and based on the ninth preset range, it is judged whether the third characteristic voltage V3 is within the normal range. If the second characteristic voltage V1 and the third characteristic voltage V3 are within the normal range, when the difference between the second characteristic voltage V1 and the third characteristic voltage V3 is less than or equal to 20V, it is determined that the fast charging positive contactor KM3 is adhered. Alternatively, when the rate of change Vv3 of the third characteristic voltage V3 is within [1V / ms, 1.6V / ms], it is determined that the fast charging positive contactor KM3 is adhered, otherwise it can be determined that the fast charging positive contactor KM3 is not adhered. If the second characteristic voltage V1 and the third characteristic voltage V3 are not within the normal range, it is determined that the state of the fast charging positive contactor KM3 is invalid.

[0074] Figure 11 A flow chart of an embodiment of a method for detecting a fast charging contactor provided in this application shows Figure 8The embodiment shown is a specific implementation method. Among them, after the control module 113 starts the process, it detects that the fast charging negative contactor KM4 is in a disconnected state, and then obtains the fourth characteristic voltage V2-2 at point A between the first voltage divider component R3 and the second voltage divider component R4 collected by the voltage acquisition module 113. And based on whether the fourth characteristic voltage V2-2 is within the twelfth preset range, the validity of the fourth characteristic voltage V2-2 is judged. If the fourth characteristic voltage V2-2 is valid, it is further judged whether the fourth characteristic voltage V2-2 is between the tenth preset range near -0.7V. If so, it is determined that the fast charging positive contactor KM3 is in a disconnected adhesion state. If not, it is determined that the fast charging positive contactor KM3 is in a conductive adhesion state. If the fourth characteristic voltage V2-2 is invalid, it is determined that the state of the fast charging positive contactor KM3 is invalid.

[0075] Figure 12 This is a flow chart of an embodiment of the detection method of the fast charging contactor provided by the present application, showing that the control module 113 Figure 10 and Figure 11 The two detection methods shown are the flow chart for detecting the fast charging positive contactor KM3. The specific implementation method can be referred to Figure 10 and Figure 11 The examples shown are not repeated here.

[0076] In the aforementioned embodiments of the present application, the detection method of the fast charging contactor provided in the embodiments of the present application is introduced. In order to realize the various functions of the method provided in the above embodiments of the present application, the control module as the execution subject can be implemented by a hardware structure and / or a software module. For example, the above functions can be realized in the form of a hardware structure, a software module, or a hardware structure plus a software module. Whether one of the above functions is executed in the form of a hardware structure, a software module, or a hardware structure plus a software module depends on the specific application and design constraints of the technical solution.

[0077] It should be understood that the division of the various modules of the above device is merely a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. Moreover, these modules can all be implemented in the form of software called by a processing element; or they can all be implemented in the form of hardware; or some modules can be implemented in the form of software called by a processing element, and some modules can be implemented in the form of hardware. For example, the processing module can be a separately established processing element, or it can be integrated into a chip of the above device. In addition, it can also be stored in the memory of the above device in the form of program code, and called by a processing element of the above device to perform the functions of the above-mentioned module. The implementation of other modules is similar. In addition, these modules can all or partly be integrated together, or they can be implemented independently. The processing element described here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each module above can be completed by an integrated logic circuit of hardware in the processor element or instructions in the form of software.

[0078] For example, the above modules can be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASICs), one or more microprocessors (digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented by scheduling program code on a processing element, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC). In the above embodiments, all or part of them can be implemented through software, hardware, firmware, or any combination thereof.

[0079] For example, Figure 13 This is a schematic diagram of the structure of an electronic device provided in this application, such as Figure 13 The device shown can be used to perform the detection method of the fast charging contactor provided in any embodiment of the present application. In one embodiment, Figure 13The electronic device 1000 shown includes one or more processors 1001 and a memory 1002. The memory 1002 is used to store computer-executable instructions, and the processor 1001 can execute the computer-executable instructions stored in the memory 1002. When the computer-executable instructions are executed by the processor 1001, the processor 1001 implements the fast-charging contactor detection method described in any of the aforementioned embodiments of the present application.

[0080] In one embodiment, if Figure 13 The electronic device 1000 shown further includes a communication interface 1003 , wherein the processor 1001 can communicate with other devices via the communication interface 1003 . For example, the processor 1001 can obtain a characteristic voltage via the communication interface 1003 .

[0081] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0082] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage.

[0083] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0084] The present application also provides a BMS, including a detection circuit of any fast charging contactor as described in the aforementioned embodiments of the present application.

[0085] The present application also provides a battery pack, including the BMS provided in the present application.

[0086] The present application also provides an electric energy device, including the battery pack provided in the embodiments of the present application. The embodiments of the present application do not limit the specific implementation of the electric energy device. In a specific implementation, the electric energy device can be an electric vehicle.

[0087] An embodiment of the present application further provides a chip for executing instructions, wherein the chip is used to execute any of the aforementioned methods for detecting fast-charging contactors in the present application.

[0088] An embodiment of the present application further provides a computer program product, including a computer program, which, when executed, implements any of the aforementioned fast-charging contactor detection methods of the present application.

[0089] The present application also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are executed, they can be used to implement the detection method of any fast-charging contactor in the aforementioned embodiments of the present application.

[0090] The readable storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0091] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0092] The division of units is merely a logical functional division; actual implementations may employ alternative divisions, such as combining or integrating multiple units or components into another system, or omitting or disabling certain features. Furthermore, any direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units, either through an interface, electrical, mechanical, or other means.

[0093] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0094] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0095] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0096] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A detection circuit for a fast charging contactor, characterized in that: include: A voltage acquisition module is used to acquire the characteristic voltage of a fast-charging contactor provided on a fast-charging circuit of the battery; A pre-charging module, used for pre-charging the main circuit of the battery; The control module is respectively connected to the voltage acquisition module and the control module, and is used to control the pre-charging module to pre-charge the main circuit of the battery before the main circuit is turned on, and when the main circuit is in the pre-charging state, determine whether the fast charging contactor is stuck according to the characteristic voltage collected by the voltage acquisition module.

2. The detection circuit according to claim 1, characterized in that The fast charging contactor provided on the fast charging circuit of the battery includes: a fast charging positive contactor and a fast charging negative contactor; The control module is specifically used to determine whether the fast charging negative contactor is stuck based on the characteristic voltage collected by the voltage acquisition module, and determine whether the fast charging positive contactor is stuck based on whether the fast charging negative contactor is closed and the characteristic voltage collected by the voltage acquisition module.

3. The detection circuit according to claim 2, characterized in that: The voltage acquisition unit includes: A first acquisition unit is used to acquire a first characteristic voltage corresponding to the fast charging negative contactor; A second acquisition unit is used to acquire a second characteristic voltage and a third characteristic voltage corresponding to the fast charging positive contactor; A third acquisition unit is used to acquire a fourth characteristic voltage corresponding to the fast charging positive contactor; The control module is specifically used to: determine whether the fast charging negative contactor is stuck based on the first characteristic voltage; and, when the fast charging negative contactor is closed, determine whether the fast charging positive contactor is stuck based on the second characteristic voltage and the third characteristic voltage; and when the fast charging negative contactor is not closed, determine whether the fast charging positive contactor is stuck based on the fourth characteristic voltage.

4. The circuit according to claim 3, characterized in that The first acquisition unit includes: a first voltage divider component, a second voltage divider component and a first diode, the first end of the first voltage divider component is connected to a voltage source, the second end of the first voltage divider component is connected to the first end of the second voltage divider component, the second end of the second voltage divider component is connected to the anode of the first diode, and the cathode of the first diode is grounded through the fast charging negative electrode contactor; The control module is specifically used to: obtain a first characteristic voltage between the first voltage divider component and the second voltage divider component, and when the first characteristic voltage is within a first preset range, determine that the fast charging negative pole contactor is stuck; when the first characteristic voltage is within a second preset range, determine that the fast charging negative pole contactor is not stuck.

5. The circuit according to claim 4, characterized in that The control module is further configured to determine that the first acquisition unit is abnormal when the first characteristic voltage is within a third preset range, and the third preset range does not overlap with the first preset range or the second preset range.

6. The circuit according to claim 4 or 5, characterized in that The second acquisition unit includes: a first switch, a second switch, a third voltage dividing component and a fourth voltage dividing component, the first end of the first switch is connected between the fast charging positive contactor and the fast charging positive interface, the second end of the first switch is connected to the fast charging negative contactor and the fast charging negative interface through the third voltage dividing component and the fourth voltage dividing component in sequence, the first end of the second switch is connected to one end of the main positive contactor, and the second end of the second switch is connected to one end of the main negative contactor; The control module is specifically used to: control the first switch and the second switch to be turned on, obtain the second characteristic voltage on both sides of the second switch, and the third characteristic voltage between the third voltage divider component and the fourth voltage divider component, and when the difference between the second characteristic voltage and the third characteristic voltage is within the fourth preset range, or the rate of change of the third characteristic voltage is within the fifth preset range, determine that the fast charging positive contactor is stuck; when the difference between the second characteristic voltage and the third characteristic voltage is within the sixth preset range, or the rate of change of the third characteristic voltage is within the seventh preset range, determine that the fast charging positive contactor is not stuck.

7. The circuit according to claim 6, characterized in that The control module is further configured to determine that the second acquisition unit is abnormal when the second characteristic voltage is within an eighth preset range, or when the third characteristic voltage is within a ninth preset range.

8. The circuit according to claim 6 or 7, characterized in that The third acquisition unit includes: a third switch, a second diode, and a third diode, wherein the anode of the second diode is connected to the first end of the first voltage divider component, the cathode of the second diode is connected to the second end of the first voltage divider component and the anode of the third diode, the cathode of the third diode is connected to the first end of the third switch, and the second end of the third switch is connected to the second end of the fourth voltage divider component; The control module is used to: control the first switch and the third switch to be turned on, obtain the fourth characteristic voltage between the first voltage divider component and the second voltage divider component, and when the fourth characteristic voltage is within the tenth preset range, determine that the fast charging positive contactor is stuck; when the fourth characteristic voltage is within the eleventh preset range, determine that the fast charging positive contactor is not stuck.

9. The circuit according to claim 8, characterized in that The control module is further configured to determine that the third acquisition unit is abnormal when the fourth characteristic voltage is within a twelfth preset range, and the twelfth preset range does not overlap with the tenth preset range or the eleventh preset range.

10. A method for detecting a fast charging contactor, characterized in that: A detection circuit for a fast-charging contactor is applied to the fast-charging contactor, the detection circuit comprising: a voltage acquisition module for acquiring a characteristic voltage of a fast-charging contactor provided on a fast-charging circuit of a battery; a pre-charging module for pre-charging the main circuit of the battery; the detection method comprising: Before the main circuit is turned on, controlling the pre-charging module to pre-charge the main circuit of the battery; When the main circuit is in a pre-charging state, whether the fast charging contactor is stuck is determined according to the characteristic voltage collected by the voltage collection module.

11. The method according to claim 10, characterized in that The fast charging contactor provided on the fast charging circuit of the battery includes a fast charging positive contactor and a fast charging negative contactor, and determining whether the fast charging contactor is stuck based on the characteristic voltage collected by the voltage collection module includes: Determining whether the fast charging negative contactor is stuck based on the characteristic voltage collected by the voltage collection module; Whether the fast charging positive contactor is stuck is determined based on whether the fast charging negative contactor is closed and the characteristic voltage collected by the voltage collection module.

12. The method according to claim 11, characterized in that The voltage acquisition unit includes: a first acquisition unit for acquiring a first characteristic voltage corresponding to the fast charging negative contactor, a second acquisition unit for acquiring a second characteristic voltage and a third characteristic voltage corresponding to the fast charging positive contactor, and a third acquisition unit for acquiring a fourth characteristic voltage corresponding to the fast charging positive contactor; The determining whether the fast charging contactor is stuck according to the characteristic voltage collected by the voltage collection module includes: determining, based on the first characteristic voltage, whether the fast-charging negative contactor is stuck; When the fast-charging negative contactor is closed, determining whether the fast-charging positive contactor is stuck according to the second characteristic voltage and the third characteristic voltage; When the fast-charging negative contactor is not closed, whether the fast-charging positive contactor is stuck is determined according to the fourth characteristic voltage.

13. The method according to claim 12, characterized in that The first acquisition unit includes: a first voltage divider component, a second voltage divider component and a first diode, the first end of the first voltage divider component is connected to a voltage source, the second end of the first voltage divider component is connected to the first end of the second voltage divider component, the second end of the second voltage divider component is connected to the positive electrode of the first diode, and the negative electrode of the first diode is grounded through the fast charging negative electrode contactor; determining whether the fast charging negative electrode contactor is stuck according to the first characteristic voltage includes: Obtaining a first characteristic voltage between the first voltage dividing component and the second voltage dividing component; When the first characteristic voltage is within a first preset range, it is determined that the fast charging negative contactor is stuck; When the first characteristic voltage is within a second preset range, it is determined that the fast charging negative electrode contactor is not stuck.

14. The method according to claim 13, characterized in that Also includes: When the first characteristic voltage is within a third preset range, it is determined that the first acquisition unit is abnormal, and the third preset range does not overlap with the first preset range or the second preset range.

15. The method according to claim 13 or 14, characterized in that The second acquisition unit includes: a first switch, a second switch, a third voltage divider component and a fourth voltage divider component, the first end of the first switch is connected between the fast charging positive contactor and the fast charging positive interface, the second end of the first switch is connected to the fast charging negative contactor and the fast charging negative interface through the third voltage divider component and the fourth voltage divider component in sequence, the first end of the second switch is connected to one end of the main positive contactor, and the second end of the second switch is connected to one end of the main negative contactor; the determining whether the fast charging positive contactor is stuck according to the second characteristic voltage and the third characteristic voltage includes: controlling the first switch and the second switch to be turned on; obtaining a second characteristic voltage across the second switch and a third characteristic voltage between the third voltage dividing component and the fourth voltage dividing component; When the difference between the second characteristic voltage and the third characteristic voltage is within a fourth preset range, or the rate of change of the third characteristic voltage is within a fifth preset range, it is determined that the fast charging positive contactor is stuck; When the difference between the second characteristic voltage and the third characteristic voltage is within a sixth preset range, or the rate of change of the third characteristic voltage is within a seventh preset range, it is determined that the fast charging positive contactor is not stuck.

16. The method according to claim 15, characterized in that Also includes: When the second characteristic voltage is within the eighth preset range, or the third characteristic voltage is within the ninth preset range, it is determined that the second acquisition unit is abnormal.

17. The method according to claim 15 or 16, characterized in that The third acquisition unit includes: a third switch, a second diode and a third diode, the anode of the second diode is connected to the first end of the first voltage divider component, the cathode of the second diode is connected to the second end of the first voltage divider component and the anode of the third diode, the cathode of the third diode is connected to the first end of the third switch, and the second end of the third switch is connected to the second end of the fourth voltage divider component; determining whether the fast charging positive contactor is stuck according to the fourth characteristic voltage includes: controlling the first switch and the third switch to be turned on; obtaining a fourth characteristic voltage between the first voltage dividing component and the second voltage dividing component; When the fourth characteristic voltage is within a tenth preset range, it is determined that the fast charging positive contactor is stuck; When the fourth characteristic voltage is within an eleventh preset range, it is determined that the fast charging positive contactor is not stuck.

18. The method according to claim 17, characterized in that Also includes: When the fourth characteristic voltage is within a twelfth preset range, it is determined that the third acquisition unit is abnormal, and the twelfth preset range does not overlap with the tenth preset range or the eleventh preset range.

19. A BMS, characterized in that: The invention comprises a adhesion detection circuit of the fast charging contactor according to any one of claims 1 to 9.

20. A battery pack, characterized in that: Comprising the BMS as claimed in claim 19.

21. An electric energy device, characterized in that: Comprising the battery pack as claimed in claim 20.

Images