Dual-channel relay, battery pack and vehicle

Abstract

The invention relates to the technical field of series-parallel connection switching, in particular to a dual-channel relay, a battery pack and a vehicle. The dual-channel relay comprises a first channel, a second channel, a driving mechanism and a transmission mechanism. Wherein the first path comprises a first movable pole piece and a first fixed electrode; the second path comprises a second movable pole piece and a second fixed electrode; the driving mechanism is connected with the first movable pole piece and used for driving the first movable pole piece to be in contact with or disconnected from the first fixed electrode; and the transmission mechanism is connected with the first movable pole piece and the second movable pole piece and is used for driving the second movable pole piece when the first movable pole piece moves, so that the second movable pole piece is in contact with or disconnected from the second fixed electrode. The problems that in the prior art, series-parallel connection pipe cutting is achieved through three relays, the system structure is complex, and cost is high can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of series-parallel switching, and in particular to a dual-channel relay, a battery pack and a vehicle. Background Art

[0002] New energy vehicles account for an increasingly high proportion in the current automotive industry. To meet users' demand for shorter charging times, 800V high-voltage charging is an important technical direction. However, in order to match the mainstream electric drive operating voltage in the market, the current voltage platform of new energy vehicle battery packs is generally between 300V and 400V, and some 500V charging piles on the market still cannot support high-voltage charging.

[0003] In order to realize the series-parallel switching of battery modules, the existing battery pack usually uses three relays to perform series-parallel switching between battery modules to achieve matching of working or charging voltages.

[0004] However, the use of three relays to achieve series-parallel switching has the problems of complex system structure and high cost. Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present invention is to provide a dual-channel relay, a battery pack and a vehicle, which can solve the problem that the prior art uses three relays to achieve series-parallel pipe cutting, which has a complex system structure and high cost.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0007] In one aspect, the present invention provides a dual-channel relay, characterized in that it comprises:

[0008] A first passage, comprising a first moving electrode and a first fixed electrode;

[0009] A second passage, comprising a second moving electrode piece and a second fixed electrode;

[0010] a driving mechanism connected to the first moving pole piece and used to drive the first moving pole piece to contact or disconnect with the first fixed electrode;

[0011] The transmission mechanism connects the first moving pole piece and the second moving pole piece, and is used to drive the second moving pole piece when the first moving pole piece moves, so that the second moving pole piece contacts or disconnects with the second fixed electrode.

[0012] In some optional solutions, the transmission mechanism includes:

[0013] A driven rack connected to the second moving pole piece and movable in a set direction;

[0014] A transmission gear meshes with the driven rack and is rotatably arranged and fixed in position;

[0015] An active rack is connected to the first moving pole piece or the driving mechanism and meshes with the transmission gear, and is used to drive the transmission gear to rotate when the first moving pole piece moves, so as to drive the driven rack to drive the second moving pole piece to move, so that the second moving pole piece contacts or disconnects with the second fixed electrode.

[0016] In some optional solutions, the dual-channel relay further includes a mounting housing, in which a guide hole is provided, and the driving mechanism includes:

[0017] A guide rod, which is movably disposed in the guide hole, with both ends extending out of the guide hole and one end connected to the first moving pole piece;

[0018] A moving iron core, which is arranged at the other end of the guide rod;

[0019] The coil is wound around the outer side of the moving iron core and is used to drive the moving iron core to push the guide rod to move in the guide hole when power is turned on, so as to drive the first moving pole piece to contact the first fixed electrode.

[0020] In some optional schemes, a first return spring is sleeved on one end of the guide rod connected to the moving iron core, and both ends of the first return spring are abutted against the moving iron core and the mounting shell to provide a restoring force to disconnect the first moving pole piece from the first fixed electrode.

[0021] In some optional schemes, a through hole is provided on the first moving pole piece, and the guide rod includes a sliding section and a buffer section, a limiting protrusion is provided between the sliding section and the buffer section, the sliding section passes through the through hole, a limiting portion is provided at the end, and a buffer spring is provided on the outer side, and both ends of the buffer spring are supported between the first moving pole piece and the limiting protrusion.

[0022] In some optional schemes, an isolation sleeve is slidably mounted on the guide rod, the isolation sleeve includes a radial isolation segment and an axial isolation segment, the radial isolation segment is located between the axial isolation segment and the limiting protrusion, a limiting sleeve is provided at the end of the guide rod, the limiting sleeve includes a limiting segment and a fixed isolation segment, the limiting segment is located on the side of the first moving pole piece away from the isolation sleeve, the fixed isolation segment passes through the through hole and is mutually mounted with the axial isolation segment, and the buffer spring is mounted on the outside of the axial isolation segment and the fixed isolation segment.

[0023] In some optional schemes, a guide groove is provided at the corresponding position of the driven rack in the mounting shell, and the driven rack includes a rack section and a guide section, and the guide section is movably arranged in the guide groove, and a supporting protrusion is provided between the rack section and the guide section, and a second return spring is sleeved on the outer side of the guide section and is supported on the supporting protrusion, so as to provide a restoring force to make the second moving pole piece contact with the second fixed electrode.

[0024] In a second aspect, the present invention further provides a battery pack, characterized in that it comprises:

[0025] A first battery module and a second battery module;

[0026] A dual-channel relay comprising:

[0027] A first passage, comprising a first moving electrode and a first fixed electrode, wherein the first passage connects the negative electrode of the first battery module and the positive electrode of the second battery module;

[0028] A second path, comprising a second moving electrode and a second fixed electrode, wherein the second path connects the positive electrode of the first battery module and the positive electrode of the second battery module;

[0029] a driving mechanism connected to the first moving pole piece and used to drive the first moving pole piece to contact or disconnect with the first fixed electrode;

[0030] A transmission mechanism, which connects the first moving pole piece and the second moving pole piece, and is used to drive the second moving pole piece when the first moving pole piece moves, so that the second moving pole piece contacts or disconnects with the second fixed electrode;

[0031] A single-channel relay connects the negative electrode of the first battery module and the negative electrode of the second battery module.

[0032] In some optional solutions, the first battery module and the second battery module are both connected in parallel with a balancing circuit, and the balancing circuit includes a balancing resistor and a balancing switch connected in series in sequence.

[0033] In a third aspect, the present invention further provides a vehicle, characterized by the above-mentioned battery pack.

[0034] Compared with the prior art, the advantages of the present invention are: in this scheme, the first moving pole piece is driven by a driving mechanism to contact or disconnect with the first fixed electrode. Since the first moving pole piece and the second moving pole piece are connected by a transmission mechanism, when the driving mechanism drives the first moving pole piece to move, the second moving pole piece is driven by the transmission mechanism to make the second moving pole piece contact or disconnect with the second fixed electrode. Specifically, when the first moving pole piece and the first fixed electrode are disengaged, the second moving pole piece contacts the second fixed electrode. When the second moving pole piece and the second fixed electrode are disengaged, the first moving pole piece contacts the first fixed electrode, so that the first path and the second path can be switched between disconnection and connection. The functions of two relays are realized by the dual-path relay, thereby simplifying the entire circuit system and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 is a schematic cross-sectional view of a dual-channel relay according to an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of a three-dimensional structure of a transmission mechanism in an embodiment of the present invention;

[0038] Figure 3 Schematic diagram of the appearance of a dual-channel relay in an embodiment of the present invention;

[0039] Figure 4 is a circuit diagram of a battery pack according to an embodiment of the present invention;

[0040] Figure 5 is a schematic diagram of a battery pack balancing circuit according to an embodiment of the present invention;

[0041] Figure 6 This is a flow chart of direct current charging when two modules are connected in series when the battery pack is discharged in an embodiment of the present invention;

[0042] Figure 7 This is a DC charging flow chart of the battery pack in the embodiment of the present invention when the two modules are in parallel state when discharging.

[0043] In the figure: 1, first passage; 11, first moving pole piece; 12, first fixed electrode; 2, second passage; 21, second moving pole piece; 22, second fixed electrode; 3, transmission mechanism; 31, driven rack; 311, abutting protrusion; 32, transmission gear; 33, active rack; 34, connecting frame; 4, driving mechanism; 41, guide rod; 411, limiting protrusion; 42, moving iron core; 43, coil; 431, coil mounting cylinder; 44, first return spring; 45, buffer spring; 46, isolation sleeve; 47, limiting sleeve; 5, second return spring; 51, stepped cylinder; 6, mounting shell; 61, base shell; 611, mounting base plate; 612, shaft cylinder; 62, cover; 63, sealing cover; 64, mounting frame; 65, permanent magnet. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0045] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0046] like Figure 1 As shown, on one hand, the present invention provides a dual-channel relay, including: a first channel 1, a second channel 2, a driving mechanism 4 and a transmission mechanism 3.

[0047] Among them, the first passage 1 includes a first moving pole piece 11 and a first fixed electrode 12; the second passage 2 includes a second moving pole piece 21 and a second fixed electrode 22; the driving mechanism 4 is connected to the first moving pole piece 11, and is used to drive the first moving pole piece 11 to contact or disconnect with the first fixed electrode 12; the transmission mechanism 3 connects the first moving pole piece 11 and the second moving pole piece 21, and is used to drive the second moving pole piece 21 when the first moving pole piece 11 moves, so that the second moving pole piece 21 contacts or disconnects with the second fixed electrode 22.

[0048] The dual-path relay includes a first state and a second state. When in the first state, the second moving pole piece 21 and the second fixed electrode 22 are in contact, so that the second path 2 is connected, the first moving pole piece 11 and the first fixed electrode 12 are separated, and the first path 1 is disconnected; when in the second state, the second moving pole piece 21 and the second fixed electrode 22 are separated, so that the second path 2 is disconnected, the first moving pole piece 11 and the first fixed electrode 12 are in contact, and the first path 1 is connected. In this solution, the first moving pole piece 11 is driven by the driving mechanism 4 to contact or disconnect with the first fixed electrode 12. Since the first moving pole piece 11 and the second moving pole piece 21 are connected by the transmission mechanism 3, when the driving mechanism drives the first moving pole piece 11 to move, the second moving pole piece 21 is driven by the transmission mechanism 3 to make the second moving pole piece 21 contact or disconnect with the second fixed electrode 22. Specifically, when the first moving pole piece 11 and the first fixed electrode 12 are disengaged, the second moving pole piece 21 and the second fixed electrode 22 are contacted. When the second moving pole piece 21 and the second fixed electrode 22 are disengaged, the first moving pole piece 11 and the first fixed electrode 12 are contacted, so that the first path 1 and the second path 2 are switched between disconnection and connection. The functions of two relays are realized by the dual-path relay, thereby simplifying the entire circuit system and reducing costs.

[0049] like Figure 2 As shown, in some optional embodiments, the transmission mechanism 3 includes: a driven rack 31, a transmission gear 32 and an active rack 33. The driven rack 31 is connected to the second moving pole piece 21 and can move in a set direction, the transmission gear 32 is meshed with the driven rack 31, and is rotatably arranged, and the position is fixed; the active rack 33 is connected to the first moving pole piece 11 or the driving mechanism 4, and is meshed with the transmission gear 32, and is used to drive the transmission gear 32 to rotate when the first moving pole piece 11 moves, so as to drive the driven rack 31 to drive the second moving pole piece 21 to move, so that the second moving pole piece 21 is in contact with or disconnected from the second fixed electrode 22.

[0050] In this embodiment, the active rack 33, the transmission gear 32 and the driven rack 31 are meshed in sequence, the active rack 33 is connected to the first moving pole piece 11, the transmission gear 32 is fixed in position and is rotatably arranged, when the driving mechanism drives the first moving pole piece 11 to move, the first moving pole piece 11 or the driving mechanism drives the active rack 33 to move, the active rack 33 drives the transmission gear 32 to rotate, and the transmission gear 32 drives the driven rack 31 to move in the opposite direction relative to the active rack 33, thereby driving the second moving pole piece 21 to move, so that the second moving pole piece 21 is in contact with or disconnected from the second fixed electrode 22. In addition, the active rack 33, the transmission gear 32 and the driven rack 31 are used as the transmission mechanism between the first moving pole piece 11 and the second moving pole piece 21, which has a certain locking function. When the driving mechanism 4 stops driving and locking, the positions of the first moving pole piece 11 and the second moving pole piece 21 can be locked, and the positions will not change due to vibration, thereby improving the stability of the connection or disconnection of the first passage 1 and the second passage 2.

[0051] In other embodiments, the transmission mechanism 3 may also adopt other structural forms. For example, the first moving pole piece 11 and the second moving pole piece 21 are connected by a lever. Specifically, the middle part of the lever is rotated, and a support ear is set under the first moving pole piece 11 or a support ear is set on the transmission mechanism 3, and a support ear is set under the second moving pole piece 21, and through holes are set on the support ears, so that the two ends of the lever are respectively extended into the through holes of the support ears under the first moving pole piece 11 and the second moving pole piece 21. When the first moving pole piece 11 moves, the end of the lever moves together, and the middle part of the lever rotates, and the other end will drive the second moving pole piece 21 to move, thereby realizing the switching of connection or disconnection between the first passage 1 and the second passage 2.

[0052] In some optional embodiments, the dual-channel relay further includes a mounting housing 6, which is provided with a guide hole, and the driving mechanism 4 includes: a guide rod 41, a moving iron core 42 and a coil 43. The guide rod 41 is movably arranged in the guide hole, and both ends extend out of the guide hole, and one end is connected to the first moving pole piece 11; the moving iron core 42 is arranged at the other end of the guide rod 41; the coil 43 is wound around the outer side of the moving iron core 42, and is used to drive the moving iron core 42 to push the guide rod 41 to move in the guide hole when power is turned on, so as to drive the first moving pole piece 11 to contact the first fixed electrode 12.

[0053] In this embodiment, the guide rod 41 is movably disposed in the guide hole, and the moving iron core 42 is fixedly connected to the guide rod 41. When it is necessary to switch from the first passage 1 disconnected and the second passage 2 connected state to the first passage 1 connected and the second passage 2 disconnected state, the coil 43 is energized to drive the moving iron core 42 to push the guide rod 41 to move in the guide hole, so as to drive the first moving pole piece 11 to contact the first fixed electrode 12. At the same time, the first moving pole piece 11 or the driving mechanism 4 drives the active rack 33 to move, the active rack 33 drives the transmission gear 32 to rotate, and the transmission gear 32 drives the driven rack 31 to move in the opposite direction relative to the active rack 33, thereby driving the second moving pole piece 21 to move, so that the second moving pole piece 21 is disconnected from the second fixed electrode 22.

[0054] In addition, in this example, the guide rod 41 is placed vertically, and when it is necessary to switch from the first passage 1 connected and the second passage 2 disconnected state to the first passage 1 disconnected and the second passage 2 connected state, the coil 43 is de-energized, and the gravity of the moving iron core 42 can be used to disengage the first moving pole piece 11 from the first fixed electrode 12, and the first moving pole piece 11 or the driving mechanism 4 drives the active rack 33 to move, the active rack 33 drives the transmission gear 32 to rotate, and the transmission gear 32 drives the driven rack 31 to move in the opposite direction relative to the active rack 33, thereby driving the second moving pole piece 21 to move, so that the second moving pole piece 21 contacts the second fixed electrode 22. The gravity of the moving iron core 42 and the self-locking characteristics when the gear and rack are engaged ensure that the second passage 2 will not be abnormally disconnected.

[0055] In other embodiments, the driving mechanism 4 may also adopt other structures, for example, adopting a telescopic rod to drive the first moving electrode piece 11 to contact or disconnect with the first fixed electrode 12 .

[0056] like Figure 1 and Figure 3 As shown, in addition, in this example, the mounting housing 6 includes a base shell 61, a cover 62 and a sealing cover 63; the base shell 61 includes a mounting substrate 611 and a shaft cylinder 612, the shaft cylinder 612 is arranged on one side of the mounting substrate 611, and a guide hole penetrating the corresponding position of the mounting substrate 611 is arranged in the shaft cylinder 612, and the cover 62 is located on the other side of the mounting substrate 611, and forms an installation space for installing the first moving pole piece 11, the second moving pole piece 21 and the transmission mechanism 3 with the mounting substrate 611. The guide rod 41 is movably arranged in the guide hole, one end of which extends into the installation space and is connected to the first moving pole piece 11, and the other end extends out of the shaft cylinder 612 and is connected to the moving iron core 42, and the sealing cover 63 is arranged on the outside of the shaft cylinder 612 and the moving iron core 42, and the end thereof is sealed and connected to the mounting substrate 611.

[0057] In addition, in this example, two first fixed electrodes 12 and two second fixed electrodes 22 are provided, and the two first fixed electrodes 12 are fixed on the cover 62 at intervals, the input line and the output line of the conductive circuit of the first passage 1 are respectively connected to the two first fixed electrodes 12, the two second fixed electrodes 22 are also fixed on the cover 62 at intervals, the input line and the output line of the conductive circuit of the second passage 2 are respectively connected to the two second fixed electrodes 22, the guide rod 41 is connected to the middle of the first moving pole piece 11, the first moving pole piece 11 is in contact with the two first fixed electrodes 12 at the same time, so as to realize the conduction of the first passage 1, and the second moving pole piece 21 is in contact with the two second fixed electrodes 22 at the same time, so as to realize the conduction of the second passage 2. In other embodiments, the first fixed electrode 12 and the second fixed electrode 22 can also be fixed on the existing mechanism, so as to realize the contact and separation with the corresponding moving pole piece.

[0058] In other embodiments, only one of the first fixed electrode 12 and the second fixed electrode 22 may be provided, the input line and the output line of the conductive circuit of the first passage 1 are connected to the first fixed electrode 12 and the first moving pole piece 11, and the input line and the output line of the conductive circuit of the second passage 2 are connected to the second fixed electrode 22 and the second moving pole piece 21 respectively, and the movement of the first moving pole piece 11 and the second moving pole piece 21, contact with or separation from the corresponding fixed electrodes, realizes the conduction or disconnection of the first passage 1 and the second passage 2, and can also achieve the same effect.

[0059] In addition, in this example, the cover 62 is in a two-step step shape, and the installation space formed by the base shell 61 and the cover 62 is in a two-step step shape. The first moving pole piece 11 is located in the first-step space of the installation space, and the second moving pole piece 21 is located in the second-step space of the installation space. The first fixed electrode 12 and the second fixed electrode 22 are respectively fixed on the cover 62 corresponding to the first moving pole piece 11 and the second moving pole piece 21, and permanent magnets 65 in a two-step step shape are provided on both sides of the cover 62. When the relay is disconnected with current, an arc will appear between the static contact and the moving contact. In this solution, the separation and disconnection of the first moving pole piece 11 and the first fixed electrode 12, or the separation and disconnection of the second moving pole piece 21 and the second fixed electrode 22, will generate a high-temperature arc. If the high-temperature arc exists for a long time, it will accelerate the aging of the relay and even cause the relay housing to crack or explode. It is necessary to extinguish the arc in a short time to control the temperature rise. Two-step stepped permanent magnets 65 are arranged on both sides of the cover 62 to generate a magnetic field with parallel magnetic flux lines. When an arc is generated, the arc is stretched to both sides to accelerate the cooling of the arc.

[0060] In some optional embodiments, a first return spring 44 is sleeved on one end of the guide rod 41 connected to the moving iron core 42, and both ends of the first return spring 44 are abutted against the moving iron core 42 and the mounting shell 6 to provide a restoring force to disconnect the first moving pole piece 11 from the first fixed electrode 12.

[0061] In this embodiment, the first return spring 44 is arranged between the moving iron core 42 and the mounting shell 6, and is supported on the moving iron core 42 and the mounting shell 6. When the coil 43 is powered on, the magnetic force provided needs to overcome the gravity of the moving iron core 42 and the elastic force of the first return spring 44; after the coil 43 is powered off, the gravity of the moving iron core 42 and the elastic force of the first return spring 44 cause the guide rod 41 to move downward, the first moving pole piece 11 is disconnected from the first fixed electrode 12, and the gear rack is engaged to achieve self-locking in the current state.

[0062] In addition, the guide hole in the shaft cylinder 612 includes a guide section and a limit section. The limit section is located near one end of the moving iron core 42. The diameter of the guide section matches the diameter of the guide rod 41. The diameter of the limit section matches the diameter of the first return spring 44. One end of the first return spring 44 is located in the limit section and the other end is abutted against the moving iron core 42. In this way, the first return spring 44 can be limited to maintain the stability of the first return spring 44.

[0063] In some optional embodiments, a through hole is provided on the first moving pole piece 11, the guide rod 41 includes a sliding section and a buffer section, a limiting protrusion 411 is provided between the sliding section and the buffer section, the sliding section passes through the through hole, a limiting portion is provided at the end, and a buffer spring 45 is provided on the outer side, and both ends of the buffer spring 45 are supported between the first moving pole piece 11 and the limiting protrusion 411.

[0064] If the guide rod 41 is rigidly connected to the first moving pole piece 11, the coil 43 is energized, driving the moving iron core 42 to push the guide rod 41 to move in the guide hole, the first moving pole piece 11 will directly hit the first fixed electrode 12, which may cause the first moving pole piece 11 to rebound or be damaged after repeated use.

[0065] In this embodiment, the sliding section can move in the through hole of the first moving pole piece 11, and both ends of the buffer spring 45 are abutted between the first moving pole piece 11 and the limiting protrusion 411. When the guide rod 41 is pushed by the moving iron core 42 and moves upward, the limiting protrusion 411 abuts against the first moving pole piece 11 above the buffer spring 45 and moves upward. After the first moving pole piece 11 contacts the first fixed electrode 12, the buffer spring 45 is compressed until the magnetic force exerted on the moving iron core 42 is balanced with the overall downward force. The buffer spring 45 can avoid hard contact between the first moving pole piece 11 and the first fixed electrode 12, play a buffering role, and improve the stability of the contact connection and the service life.

[0066] When the coil 43 is de-energized, the guide rod 41 moves downward under the action of the elastic force of the buffer spring 45, the gravity of the moving iron core 42 and the elastic force of the first return spring 44. The limiting portion at the end of the guide rod 41 drives the first moving pole piece 11 to move, disconnect from the first fixed electrode 12, and engage with the gear rack to achieve self-locking in the current state.

[0067] In addition, the diameter of the limiting protrusion 411 is larger than the diameter of the guide hole, which can play a limiting role when the guide rod 41 moves downward. An annular groove is provided at the corresponding position of the base shell 61, and when the coil 43 is powered off, the limiting protrusion 411 is stuck in the annular groove.

[0068] In some optional embodiments, an isolation sleeve 46 is slidably mounted on the guide rod 41, and the isolation sleeve 46 includes a radial isolation segment and an axial isolation segment. The radial isolation segment is located between the axial isolation segment and the limiting protrusion 411. A limiting sleeve 47 is provided at the end of the guide rod 41. The limiting sleeve 47 includes a limiting segment and a fixed isolation segment. The limiting segment is located on the side of the first moving pole piece 11 away from the isolation sleeve 46. The fixed isolation segment passes through the through hole and is mutually mounted with the axial isolation segment. The buffer spring 45 is mounted on the outside of the axial isolation segment and the fixed isolation segment.

[0069] In this embodiment, the limiting section of the limiting sleeve 47 is the limiting part set at the end of the guide rod 41. The first moving pole piece 11 is connected to a 400V or 800V strong current. In order to separate the strong current from other parts to ensure the safety of electricity use, the isolation sleeve 46 and the limiting sleeve 47 are made of insulating materials. The limiting sleeve 47 is fixedly connected to the guide rod 41. The fixed isolation section is sleeved on the outside of the guide rod 41 to separate the guide rod 41 from the first moving pole piece 11. The limiting section located on the side of the first moving pole piece 11 away from the isolation sleeve 46 has a diameter greater than the diameter of the through hole, so that when the coil 43 is powered off, the guide rod 41 can pull back the first moving pole piece 11 through the limiting section to separate the first moving pole piece 11 from the first fixed electrode 12. The radial isolation section is located between the axial isolation section and the limiting protrusion 411. The diameter of the radial isolation section is larger than the diameter of the axial isolation section, which can isolate the buffer spring 45 from the limiting protrusion 411. The fixed isolation section and the axial isolation section are mutually sleeved, partially overlapped in the axial direction, and can move relatively. The buffer spring 45 is sleeved on the outside of the axial isolation section and the fixed isolation section, which can achieve isolation of the buffer spring 45 from the guide rod 41 and play a role of guiding and limiting.

[0070] Therefore, in this example, the guide rod 41 is made of iron material, and the outer side of the shaft tube 612 is also wound with a coil 43, so that when the coil 43 is energized, it can also generate an upward driving force on the guide rod 41.

[0071] The outer side of the sealing cover 63 is also covered with a coil mounting tube 431 , and bosses are provided at both ends of the coil mounting tube. The coil 43 is wound around the outer side of the coil mounting tube 431 and is located between the bosses at both ends. The bosses can limit the position of the coil 43 .

[0072] In this example, the active rack 33 is connected to the limiting section of the limiting sleeve 47 through a bracket through a connecting frame 34 .

[0073] In some optional embodiments, a guide groove is provided at a corresponding position of the driven rack 31 in the mounting shell 6, and the driven rack 31 includes a rack section and a guide section, the guide section is movably arranged in the guide groove, and a supporting protrusion 311 is provided between the rack section and the guide section, and a second return spring 5 is sleeved on the outer side of the guide section and is supported on the supporting protrusion 311, so as to provide a restoring force to make the second moving pole piece 21 contact with the second fixed electrode 22.

[0074] In this embodiment, the guide groove and the guide hole have the same orientation, and a supporting protrusion 311 is provided between the rack section and the guide section. The second reset spring 5 is supported on the supporting protrusion 311 to provide a restoring force to make the second moving pole piece 21 contact the second fixed electrode 22. When the coil 43 is powered off, the second reset spring 5 pushes the supporting protrusion 311, and at the same time, under the action of the gravity of the moving iron core 42 and the elastic force of the first reset spring 44, the driven rack 31 moves upward through the transmission of the transmission mechanism 3, and the second moving pole piece 21 contacts the second fixed electrode 22. In addition, when the coil 43 is powered off, the driven rack 31 moves downward, and the second reset spring 5 can absorb the downward stroke and impact of the driven rack 31.

[0075] In this example, the driven rack 31 also includes a connecting section, which is located above the rack section. A through hole is provided in the middle of the second moving pole piece 21, and the connecting section extends into the through hole. The connecting section is provided with limiting plates located on both sides of the second moving pole piece 21, so that the entire driven rack 31 is fixedly connected to the second moving pole piece 21 and moves synchronously.

[0076] A mounting frame 64 is also provided in the installation space. The mounting frame 64 includes a mounting plate and two limiting cylinders. The mounting plate is fixedly connected to the mounting base plate 611. The mounting plate is provided with limiting holes for respectively passing the guide section of the guide rod 41 and the driven rack 31. The two limiting cylinders are respectively provided at the limiting holes and have the same inner diameter as the limiting holes. They are located on the side away from the mounting base plate 611. In this example, the mounting plate and the two limiting cylinders are integrally formed. The isolation sleeve 46 is provided in the limiting hole and the limiting cylinder through which the guide rod 41 passes. The limiting hole and the corresponding limiting cylinder through which the guide section of the driven rack 31 passes are provided with a stepped cylinder 51. The stepped cylinder 51 has a stepped hole. The diameter of the small hole is the same as the diameter of the guide section. The diameter of the large hole is the same as the outer diameter of the second reset spring 5. The second reset spring 5 is located in the large hole. The stepped cylinder 51 can play a limiting role for the driven rack 31 and the second reset spring 5.

[0077] like Figure 4 As shown, in a second aspect, the present invention further provides a battery pack, comprising: a first battery module, a second battery module, a dual-channel relay and a single-channel relay.

[0078] The dual-channel relay includes a first channel 1, a second channel 2, a driving mechanism 4 and a transmission mechanism 3. The first channel 1 includes a first moving pole piece 11 and a first fixed electrode 12; the second channel 2 includes a second moving pole piece 21 and a second fixed electrode 22; the driving mechanism 4 is connected to the first moving pole piece 11, and is used to drive the first moving pole piece 11 to contact or disconnect with the first fixed electrode 12; the transmission mechanism 3 connects the first moving pole piece 11 and the second moving pole piece 21, and is used to drive the second moving pole piece 21 when the first moving pole piece 11 moves, so that the second moving pole piece 21 contacts or disconnects with the second fixed electrode 22; the single-channel relay connects the negative electrode of the first battery module and the negative electrode of the second battery module.

[0079] When the first channel 1 channel a of the dual-channel relay K1 is closed, the second channel 2 channel b is disconnected, and the single-channel relay K2 is disconnected, the first battery module A is connected in series with the second battery module B, and the voltage across the external terminals of the battery pack is the sum of the voltages of the two modules. In this example, the first battery module and the second battery module are both 400V, which is 800V after series connection; when the second channel 1 channel b of the dual-channel relay K1 is closed, the first channel 2 channel a is disconnected, and the single-channel relay K2 is closed, the first battery module A is connected in parallel with the second battery module B, and the voltage across the external terminals of the battery pack is the voltage of the single module, which is 400V in this example.

[0080] In this solution, the first moving pole piece 11 is driven by the driving mechanism 4 to contact or disconnect with the first fixed electrode 12. Since the first moving pole piece 11 and the second moving pole piece 21 are connected by the transmission mechanism 3, when the driving mechanism drives the first moving pole piece 11 to move, the second moving pole piece 21 is driven by the transmission mechanism 3 to make the second moving pole piece 21 contact or disconnect with the second fixed electrode 22. The functions of two relays are realized by the dual-channel relay, thereby simplifying the entire circuit system and reducing costs.

[0081] A relay K4 and a fuse are provided on the positive circuit of the first battery module A. The positive circuit is used to connect to the positive electrode of the high-voltage load and the external power supply. The relay K4 is connected in parallel with a charging protection circuit. The charging protection circuit is provided with a relay K3 and a protection resistor R1 connected in series. When charging, K4 is disconnected first and K3 is connected. When the voltage across K4 is less than the set value, generally the set value is 10V, K3 is disconnected and K4 is connected to prevent the high voltage from burning the relay K4.

[0082] A current sensor and a relay K5 are arranged in sequence on the negative electrode circuit of the second battery module B. The negative electrode circuit is used to connect the negative electrode of the high-voltage load, and the current sensor is used to detect the current. An external circuit is connected between the current sensor and the relay K5, and K6 is arranged on the external circuit.

[0083] The battery pack also includes a control unit, which is connected to K1, K2, K3, K4, K5 and K6 signals and is used to control the disconnection and conduction of K1, K2, K3, K4, K5 and K6.

[0084] See also Figure 5 In some optional embodiments, the first battery module and the second battery module are both connected in parallel with a balancing circuit, and the balancing circuit includes a balancing resistor and a balancing switch connected in series in sequence.

[0085] When the first battery module A and the second battery module B are in series connection for a long time, the inconsistency between the two modules increases due to the influence of the battery cell manufacturing process, resulting in a potential difference between the first battery module A and the second battery module B. When the two modules are switched from series connection to parallel connection, this potential difference will generate a circulating current between the two modules, making the voltages of the two modules tend to be consistent. Generally speaking, the process of using circulating current to balance the two modules is very slow. Figure 5 As shown, a balancing resistor and a balancing switch are connected in parallel at both ends of the first battery module A and the second battery module B, so as to balance the two modules. By selecting a reasonable resistance value, the balancing process between the modules can be greatly accelerated. The specific method is as follows:

[0086] When the first battery module A and the second battery module B are in series connection, the control unit obtains the total voltage of the two modules through the voltage acquisition circuit. This voltage can be obtained by arranging the positive and negative voltage sampling points of the two modules, or by accumulating the sampling monomer voltage. When the voltage difference between the two modules is greater than the set threshold, if the voltage of the first battery module A is greater than that of the second battery module B, the balancing switch A is closed; if the voltage of the second battery module B is greater than that of the first battery module A, the balancing switch B is closed. After the balancing switch is closed, the control unit collects the total voltage of the two modules at a certain period, and when the difference between the total voltages of the two modules is less than the set value, the balancing switch is disconnected.

[0087] The balancing switch is a semiconductor switch or relay, such as a MOSFET, a HEMT, a PhotoMOS, a SSR, a load switch, a SmartMOS or an optically coupled relay.

[0088] The balancing switch and the balancing resistor can both be integrated into the control unit; or the balancing switch can be integrated into the control unit, and the balancing resistor can be integrated into the electrical compartment. The heat generated by the balancing resistor during balancing can be cooled by active cooling, such as air cooling, water cooling or direct cooling.

[0089] In addition, the structure of the dual-channel relay is the same as that in the above-mentioned embodiment of the dual-channel relay, and will not be described in detail here.

[0090] In a third aspect, the present invention further provides a series-parallel control method for a battery pack and a battery module, which is used to control the above-mentioned battery pack, comprising the following steps:

[0091] If both the first battery module and the second battery module are connected in parallel with a balancing circuit, the balancing step of the battery module is performed first:

[0092] like Figure 6 As shown, when the two modules are in series during discharge, when the vehicle needs to be charged with DC, the first step is to connect the fast charging gun, the vehicle control unit wakes up the battery control unit, and detects the inconsistency between the two battery modules after the low-voltage power-on self-test passes. The specific method is to obtain the total voltage of the two modules through the detection points arranged on the positive and negative terminals of the two modules, or to obtain the total voltage of the two modules by accumulating the sampled voltages of the module monomers.

[0093] If the voltage difference between the two modules is greater than the set value for entering the balancing mode, proceed to the next step; if the voltage difference between the two modules is greater than the set value, execute the balancing process, close the balancing switch connected in parallel at both ends of the module with a larger voltage, until the voltage difference between the two modules is less than the set value for exiting the balancing mode, and proceed to the next step.

[0094] Detect whether the charging pile is a high-voltage pile;

[0095] The specific method is that the battery control unit sends a gradually increasing voltage signal to the charging pile to observe whether the charging pile can follow. If the charging pile can still follow after the sent voltage is greater than the set value, the charging pile is judged to be a high-voltage pile and the high-voltage process is executed; if the charging pile cannot follow after the sent voltage is greater than the set value, the charging pile is judged not to be a high-voltage pile, and the battery control unit switches the two modules from series to parallel through the series-parallel switching circuit, and then executes the high-voltage process. Specifically, the second channel b of the dual-channel relay K1 is closed, the first channel a is disconnected, and the single-channel relay K2 is closed.

[0096] In this example, the series-parallel switching circuit is a circuit in which a dual-channel relay K1 and a single-channel relay K2 are connected to the first battery module and the second battery module.

[0097] After the high voltage is applied, the vehicle control unit sends a signal to allow charging, the battery pack starts charging, and after charging is completed, the low voltage process is executed.

[0098] Specifically. After the high voltage is lowered, the control unit detects whether the two modules are in series. If the two modules are in series, the charging gun is disconnected; if the two modules are in parallel, the battery control unit switches the two modules from parallel to series through the series-parallel switching circuit, and then disconnects the charging gun. Specifically, the first channel 1 channel a of the dual-channel relay K1 is closed, the second channel 2 channel b is disconnected, and the single-channel relay K2 is disconnected.

[0099] like Figure 7As shown in the figure, when discharging, the two modules are in parallel state. When the vehicle is DC charged, the first step is to connect the fast charging gun first, and the vehicle control unit wakes up the battery control unit. After the low-voltage power-on self-test passes, it detects whether the charging pile is a high-voltage pile. If the charging pile is judged not to be a high-voltage pile, the high-voltage process is executed; if the charging pile is judged to be a high-voltage pile, the battery control unit switches the two modules from parallel to series state through the series-parallel switching circuit, and then executes the high-voltage process.

[0100] After the high voltage is completed, the vehicle control unit sends a signal to allow charging, the battery pack starts charging, and the low voltage process is executed after charging is completed. After the high voltage is completed, the control unit detects whether the two modules are in parallel. If the two modules are in parallel, the connection of the charging gun is disconnected; if the two modules are in series, the battery control unit switches the two modules from parallel to parallel through the series-parallel switching circuit, and then disconnects the charging gun.

[0101] In a fourth aspect, the present invention further provides a vehicle, comprising the above-mentioned battery pack.

[0102] In this example, the structure of the battery pack is the same as that in the above-mentioned embodiment of the battery pack, and will not be described in detail here.

[0103] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying 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 present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0104] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including 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, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0105] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A dual-channel relay, characterized in that: include: A first passage (1) comprising a first moving electrode (11) and a first fixed electrode (12); A second passage (2), comprising a second moving electrode (21) and a second fixed electrode (22); a driving mechanism (4), connected to the first moving pole piece (11), and used for driving the first moving pole piece (11) to contact or disconnect with the first fixed electrode (12); A transmission mechanism (3) is connected to the first moving pole piece (11) and the second moving pole piece (21), and is used to drive the second moving pole piece (21) when the first moving pole piece (11) moves, so that the second moving pole piece (21) contacts or disconnects with the second fixed electrode (22).

2. The dual-channel relay according to claim 1, characterized in that: The transmission mechanism (3) comprises: A driven rack (31), which is connected to the second moving pole piece (21) and can move along a set direction; A transmission gear (32) meshes with the driven rack (31) and is rotatably arranged and fixed in position; An active rack (33) is connected to the first moving pole piece (11) or the driving mechanism (4) and meshes with the transmission gear (32) and is used to drive the transmission gear (32) to rotate when the first moving pole piece (11) moves, so as to drive the driven rack (31) to drive the second moving pole piece (21) to move, so that the second moving pole piece (21) contacts or disconnects with the second fixed electrode (22).

3. The dual-channel relay according to claim 1 or 2, characterized in that: It also includes a mounting shell (6) having a guide hole therein, and the driving mechanism (4) includes: A guide rod (41) which is movably disposed in the guide hole, with both ends extending out of the guide hole and one end connected to the first moving pole piece (11); A moving iron core (42) disposed at the other end of the guide rod (41); The coil (43) is wound around the outer side of the moving iron core (42) and is used to drive the moving iron core (42) to push the guide rod (41) to move in the guide hole when power is turned on, so as to drive the first moving pole piece (11) to contact the first fixed electrode (12).

4. The dual-channel relay according to claim 3, characterized in that: A first return spring (44) is sleeved on one end of the guide rod (41) connected to the moving iron core (42), and both ends of the first return spring (44) are abutted against the moving iron core (42) and the mounting shell (6) to provide a restoring force for disconnecting the first moving pole piece (11) from the first fixed electrode (12).

5. The dual-channel relay according to claim 4, characterized in that: A through hole is provided on the first moving pole piece (11), and the guide rod (41) comprises a sliding section and a buffer section, a limiting protrusion (411) is provided between the sliding section and the buffer section, the sliding section passes through the through hole, a limiting portion is provided at the end, and a buffer spring (45) is sleeved on the outside, and both ends of the buffer spring (45) are abutted between the first moving pole piece (11) and the limiting protrusion (411).

6. The dual-channel relay according to claim 5, characterized in that: An isolation sleeve (46) is slidably mounted on the guide rod (41), the isolation sleeve (46) comprising a radial isolation section and an axial isolation section, the radial isolation section being located between the axial isolation section and the limiting protrusion (411), a limiting sleeve (47) is provided at the end of the guide rod (41), the limiting sleeve (47) comprising a limiting section and a fixed isolation section, the limiting section being located on the side of the first moving pole piece (11) away from the isolation sleeve (46), the fixed isolation section passes through the through hole and is mutually mounted with the axial isolation section, and the buffer spring (45) is mounted on the outside of the axial isolation section and the fixed isolation section.

7. The dual-channel relay according to claim 3, characterized in that: A guide groove is provided at a position corresponding to the driven rack (31) in the mounting shell (6); the driven rack (31) comprises a rack section and a guide section; the guide section is movably arranged in the guide groove; a supporting protrusion (311) is provided between the rack section and the guide section; a second return spring (5) is sleeved on the outer side of the guide section and is supported on the supporting protrusion (311) to provide a restoring force for bringing the second moving pole piece (21) into contact with the second fixed electrode (22).

8. A battery pack, characterized in that: include: A first battery module and a second battery module; A dual-channel relay comprising: A first passage (1), comprising a first moving electrode (11) and a first fixed electrode (12), wherein the first passage (1) connects the negative electrode of the first battery module and the positive electrode of the second battery module; A second passage (2), comprising a second moving electrode (21) and a second fixed electrode (22), wherein the second passage (2) connects the positive electrode of the first battery module and the positive electrode of the second battery module; a driving mechanism (4), connected to the first moving pole piece (11), and used for driving the first moving pole piece (11) to contact or disconnect with the first fixed electrode (12); a transmission mechanism (3) connecting the first moving pole piece (11) and the second moving pole piece (21) and used for driving the second moving pole piece (21) when the first moving pole piece (11) moves, so that the second moving pole piece (21) contacts or disconnects with the second fixed electrode (22); A single-channel relay connects the negative electrode of the first battery module and the negative electrode of the second battery module.

9. The battery pack according to claim 8, characterized in that: The first battery module and the second battery module are both connected in parallel with a balancing circuit, and the balancing circuit includes a balancing resistor and a balancing switch connected in series in sequence.

10. A vehicle, characterized in that: Comprising a battery pack as claimed in claim 8 or 9.

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