Charging circuit, equalization circuit, charging system, battery system, power utilization system and vehicle

Abstract

The utility model relates to a charging circuit, an equalization circuit, a charging system, a battery system, a power utilization system and a vehicle. The charging circuit comprises a first output end, a second output end, a first one-way switch and a change-over switch, and the change-over switch is connected between the first output end and the second output end; the first one-way switch is respectively connected with the first output end and the second output end, the first one-way switch is used for one-way conduction between the first output end and the second output end, the first output end is used for being connected with a first battery pack, and the second output end is used for being connected with a second battery pack.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically, to a charging circuit, an equalization circuit, a charging system, a battery system, a power system and a vehicle. Background Art

[0002] With the increasing awareness of environmental protection, new energy vehicles are gradually becoming popular. At present, new energy vehicles are usually equipped with multiple power battery packs to improve their endurance. In the process of charging multiple battery packs, it is often necessary to switch the charging mode to adapt to different charging needs. For example, switching between multiple battery packs in series and parallel charging modes. Another example is switching between multiple battery packs in series charging mode and single battery pack charging mode. At present, when switching the charging mode, it is necessary to disconnect the charging circuit from the power supply before switching the charging mode, otherwise a short circuit will occur.

[0003] However, when switching the charging mode and disconnecting the charging pile, a sudden voltage will be generated at the power supply, which may not only trigger the power supply's own protection strategy and terminate charging, but also damage the power supply itself and the contactor on the vehicle side. Therefore, it is necessary to provide a new charging solution to avoid the above risks. Summary of the invention

[0004] An object of the embodiments of the present application is to provide a charging circuit, a balancing circuit, a charging system, a battery system, a power system and a vehicle.

[0005] According to a first aspect of the present application, a charging circuit is provided, comprising: a first output terminal, a second output terminal, a first unidirectional switch, and a switching switch.

[0006] The switch is connected between the first output terminal and the second output terminal;

[0007] The first unidirectional switch is connected to the first output end and the second output end respectively, and is used for unidirectional conduction between the first output end and the second output end. The first output end is used to connect to a first battery pack, and the second output end is used to connect to a second battery pack.

[0008] Optionally, the charging circuit further includes an input terminal, a first switching module and a second switching module.

[0009] The first end of the first switching module is connected to the first end of the input end, the second end of the first switching module is connected to the first output end, and the third end of the first switching module is connected between the first unidirectional switch and the second output end;

[0010] The first end of the second switching module is connected to the second end of the input end, the second end of the second switching module is connected between the first unidirectional switch and the first output end, and the third end of the second switching module is connected to the second output end.

[0011] Optionally, the first switching module includes a first switch unit, a second switch unit and a pre-charging resistor, wherein a first end of the pre-charging resistor is connected to the input end, and a second end of the pre-charging resistor is connected to the first switch unit and the second switch unit respectively;

[0012] A first end of the first switch unit is connected to the input end, a second end of the first switch unit is connected to the first output end, and a third end of the first switch unit is connected to the second end of the pre-charging resistor;

[0013] The first end of the second switch unit is connected to the input end, the second end of the second switch unit is connected between the second output end and the first unidirectional switch, and the third end of the second switch unit is connected to the second end of the pre-charging resistor.

[0014] Optionally, the first switch unit includes a first switch and a second switch, the first switch is connected between the first end of the input end and the first output end, and the second switch is connected between the second end of the pre-charging resistor and the first output end.

[0015] Optionally, the second switch unit includes a third switch and a fourth switch, the first end of the third switch is connected to the first end of the input end, the second end of the third switch is connected between the first unidirectional switch and the second output end, the first end of the fourth switch is connected to the second end of the pre-charging resistor, and the second end of the fourth switch is connected between the first unidirectional switch and the second output end.

[0016] Optionally, the second switching module includes a fifth switch and a sixth switch;

[0017] A first end of the fifth switch is connected to a second end of the input end, and a second end of the fifth switch is connected between the first unidirectional switch and the first output end;

[0018] A first end of the sixth switch is connected to a second end of the input end, and a second end of the sixth switch is connected to the second output end.

[0019] Optionally, the charging circuit further includes a second unidirectional switch, wherein the second unidirectional switch is connected between the second end of the first switching module and the first output end; or,

[0020] The charging circuit further includes a third unidirectional switch, a first end of the third unidirectional switch is connected to the third end of the first switching module, and a second end of the third unidirectional switch is connected between the second output end and the first unidirectional switch; or,

[0021] The charging circuit further includes a fourth unidirectional switch connected between the third terminal of the second switching module and the second output terminal; or,

[0022] The charging circuit further includes a fifth unidirectional switch, a first end of the fifth unidirectional switch is connected to the second end of the first switching module, and a second end of the fifth unidirectional switch is connected between the first output end and the first unidirectional switch.

[0023] According to a second aspect of the present application, there is provided an equalization circuit, comprising: a switching module and a switching switch,

[0024] The two ends of the switching module are respectively connected to the first battery pack and the second battery pack, and the switching module is used to perform voltage balancing on the first battery pack and the second battery pack; the switching module is also used to discharge the first battery pack and / or the second battery pack;

[0025] The switch is connected between the first battery pack and the second battery pack.

[0026] Optionally, the first end of the switching module is connected to the first end of the first battery pack, the second end of the switching module is connected to the first end of the second battery pack, and the second end of the first battery pack is connected to the second end of the second battery pack.

[0027] Optionally, the switching module includes an eighth switch, a ninth switch and a first resistor, the eighth switch is connected between the first end of the switching module and the second end of the switching module, and the ninth switch and the first resistor are connected in series between the first end of the switching module and the second end of the switching module.

[0028] Optionally, the switching module further includes a tenth switch, an eleventh switch, and a second resistor, wherein the eleventh switch and the second resistor are connected in series and then connected in parallel with the tenth switch;

[0029] The eighth switch, the ninth switch and the first resistor constitute a first switching module, the tenth switch, the eleventh switch and the second resistor constitute a second switching module, and the first switching module and the second switching module are connected in series to constitute the switching module.

[0030] Optionally, the first resistor is greater than the second resistor.

[0031] Optionally, the balancing circuit further includes an output end, the third end of the switching module is further used to connect to the output end, and the output end is used to discharge the load.

[0032] According to a third aspect of the present application, a charging system is provided, comprising a charging circuit as described in any one of the first aspects.

[0033] According to a fourth aspect of the present application, a battery system is provided, comprising the balancing circuit as described in any one of the second aspects, a first battery pack and a second battery pack.

[0034] According to a fifth aspect of the present application, there is provided a power consumption system, comprising the battery system and a load as described in the fourth aspect.

[0035] According to a sixth aspect of the present application, a vehicle is provided, comprising a system as described in any one of the third to fifth aspects.

[0036] One beneficial effect of an embodiment of the present application is that, by setting a one-way switch between the first output terminal and the second output terminal of the charging circuit, when the charging mode is switched, the first output terminal and the second output terminal are one-way connected and disconnected in the reverse direction. When the charging circuit is switched from the first charging mode to the second charging mode, the circuit corresponding to the second charging mode can be directly connected without disconnecting the switching switch first, so that the connection between the charging circuit and the power supply will not be disconnected, thereby avoiding the risk of termination of charging due to a sudden voltage change in the power supply, triggering the power supply's own protection strategy, and damaging the power supply itself and the contactor on the vehicle end. Moreover, even if the switching switch is damaged, the circuit will not have the risk of short circuit. In addition, the one-way switch and the switching switch work together to further achieve double protection.

[0037] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0039] Figure 1 It is a circuit diagram of a charging circuit provided according to an embodiment of the present application.

[0040] Figure 2 It is a circuit diagram of a charging circuit provided according to another embodiment of the present application.

[0041] Figure 3 It is a circuit diagram of an equalizing circuit provided according to an embodiment of the present application.

[0042] Figure 4 is a circuit diagram of an equalizing circuit provided according to another embodiment of the present application.

[0043] Figure 5 It is a circuit diagram of an integrated charging circuit and an equalizing circuit provided according to another embodiment of the present application.

[0044] Figure 6 It is a structural schematic diagram of an electricity consumption system provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0045] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0046] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0047] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0048] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0049] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0050] The system of the embodiment of the present application can be applied to electric vehicle charging and discharging scenarios. In the charging scenario, it can be applied to wireless charging or wired charging. Multiple battery packs in series can be charged, and multiple battery packs in parallel can be charged. After one of the battery packs is fully charged, other battery packs can continue to be charged separately. In the discharge scenario, the load can be powered by multiple battery packs in series, or by one of the battery packs. The system of the embodiment of the present application may include a charging system, a battery system, or a power consumption system. The charging system may include a charging circuit. The battery system may include a balancing circuit and a battery pack. The power consumption system may include a battery system and a load.

[0051] The present application embodiment takes into account the problem that the current charging circuit needs to disconnect from the power supply before switching the charging mode, and proposes a new charging circuit. Figure 1As shown, the charging circuit includes: a first output terminal 100, a second output terminal 110, a first unidirectional switch 120, and a switching switch 160. The switching switch 160 is connected between the first output terminal 100 and the second output terminal 110. The first unidirectional switch 120 is connected between the first output terminal 100 and the second output terminal 110, and the first unidirectional switch 120 is used for unidirectional conduction between the first output terminal 100 and the second output terminal 110. The first output terminal 100 is used to connect to the first battery pack, and the second output terminal 110 is used to connect to the second battery pack.

[0052] The working state of the charging circuit of the embodiment of the present application may include a first charging state and a second charging state. The first charging state is that the first output terminal 100 and the second output terminal 110 are discharged in series. The second charging state is that the first output terminal 100 and the second output terminal 110 are discharged in parallel. Alternatively, the second charging state is that the first output terminal 100 is discharged alone or the second output terminal 110 is discharged alone.

[0053] In this embodiment, the first output terminal 100 is used to connect to the first battery pack. The first output terminal 100 can be understood as two ports connected to the positive and negative electrodes of the first battery pack. In one example, the first output terminal can be as follows: Figure 1 Two ports 100 are shown. The first battery pack is discharged through the first output port 100 .

[0054] Similarly, the second output terminal 110 is used to connect to the second battery pack. The second output terminal 110 can be understood as two ports connected to the positive and negative electrodes of the second battery pack. In one example, the second output terminal can be as follows: Figure 1 Two ports 110 are shown. The second battery pack is discharged through the second output port 110 .

[0055] In this embodiment, the first unidirectional switch 120 may be any element having a unidirectional conduction function, such as a diode, which is not specifically limited here.

[0056] In this embodiment, the first unidirectional switch 120 is connected between the first output terminal 100 and the second output terminal 110. In one example, the first unidirectional switch 120 is connected between the first output terminal 100 connected to the negative electrode of the first battery pack and the second output terminal 110 connected to the positive electrode of the second battery pack.

[0057] In this embodiment, when the charging circuit is switched from the first charging state to the second charging state, the first unidirectional switch 120 is switched from unidirectional conduction to reverse conduction.

[0058] In this embodiment, the switch 160 can be any switch device, such as a contactor or a relay. By controlling the on and off of the switch 160, the charging circuit can be switched between the first charging state and the second charging state. Figure 2 As shown, the switch 160 may be, for example, the switch K7.

[0059] This embodiment sets a one-way switch between the first output terminal and the second output terminal of the charging circuit, so that when the charging mode is switched, the first output terminal and the second output terminal are unidirectionally connected and disconnected in the reverse direction. When the charging circuit is switched from the first charging mode to the second charging mode, the circuit corresponding to the second charging mode can be directly connected without disconnecting the switching switch first, so that the connection between the charging circuit and the power supply will not be disconnected, thereby avoiding the risk of termination of charging due to a sudden voltage change in the power supply, triggering the power supply's own protection strategy, and damaging the power supply itself and the contactor on the vehicle end. Moreover, even if the switching switch is damaged, the circuit will not have the risk of short circuit. In addition, the one-way switch and the switching switch work together to further achieve double protection.

[0060] In some embodiments, Figure 1 As shown, the charging circuit may further include an input terminal 130, a first switching module 140, and a second switching module 150. A first end of the first switching module 140 is connected to a first end of the input terminal 130, a second end of the first switching module 140 is connected to a first output terminal 100, and a third end of the first switching module 140 is connected between the first unidirectional switch 120 and the second output terminal 110. A first end of the second switching module 150 is connected to a second end of the input terminal 130, a second end of the second switching module 150 is connected between the first unidirectional switch 120 and the first output terminal 100, and a third end of the second switching module 150 is connected to the second output terminal 110.

[0061] In this embodiment, the first end of the input terminal 130 and the second end of the input terminal 130 may be two ends for connecting the charging circuit to the positive and negative electrodes of the power source, respectively.

[0062] In one example, the first end of the input terminal 130 may be a positive terminal, and the second end of the input terminal 130 may be a negative terminal. The second end of the first switching module 140 is connected to the first output terminal 100 connected to the positive electrode of the first battery pack. The third end of the first switching module 140 is connected between the first unidirectional switch 120 and the second output terminal 110 connected to the positive electrode of the second battery pack. The second end of the second switching module 150 is connected between the first unidirectional switch 120 and the first output terminal 100 connected to the negative electrode of the first battery pack. The third end of the second switching module 150 is connected to the second output terminal 110 connected to the negative electrode of the second battery pack.

[0063] When the charging circuit of this embodiment is in the first charging state, the first end of the first switching module 140 is connected to the second end of the first switching module 140 , and the first end of the second switching module 150 is connected to the third end of the second switching module 150 .

[0064] The second charging state may be that the first output end and the second output end are discharged in parallel. When the charging circuit of the present embodiment is in the second charging state, the first end of the first switching module 140 and the second end of the first switching module 140 are connected, and the first end of the second switching module 150 and the second end of the second switching module 150 are connected. Also, the first end of the first switching module 140 and the third end of the first switching module 140 are connected, and the first end of the second switching module 150 and the third end of the second switching module 150 are connected. In the present embodiment, when the charging circuit is switched from the first charging state to the second charging state, after the first unidirectional switch is switched from unidirectional conduction to reverse disconnection, the first end of the first switching module and the third end of the first switching module are connected, and the first end of the second switching module and the second end of the second switching module are connected first, and then the switch is disconnected.

[0065] The second charging state can also be that the first output end is discharged alone. When the charging circuit of this embodiment is in the second charging state, the first end of the first switching module 140 is connected to the second end of the first switching module 140, and the first end of the second switching module 150 is connected to the second end of the second switching module 150. In this embodiment, when the charging circuit is switched from the first charging state to the second charging state, after the first unidirectional switch is switched from unidirectional conduction to reverse disconnection, the first end of the first switching module 140 is connected to the second end of the first switching module 140, the first end of the second switching module 150 is connected to the second end of the second switching module 150, and then the switch is disconnected, and the connection between the first end of the second switching module 150 and the third end of the second switching module 150 is disconnected.

[0066] The second charging state can also be a separate discharge of the second output end. When the charging circuit of this embodiment is in the second charging state, the first end of the first switching module 140 is connected to the third end of the first switching module 140, and the first end of the second switching module 150 is connected to the third end of the second switching module 150. In this embodiment, when the charging circuit is switched from the first charging state to the second charging state, after the first unidirectional switch is switched from unidirectional conduction to reverse disconnection, the first end of the first switching module and the third end of the first switching module are first connected, and then the switch is disconnected, and the connection between the first end of the first switching module and the second end of the first switching module is disconnected.

[0067] Due to the provision of the first unidirectional switch in the embodiment of the present application, when the charging circuit is switched from the first charging state to the second charging state, the circuit in the second charging state can be connected first and then the circuit in the first charging state can be disconnected, thereby realizing the function of switching the charging mode without disconnecting the connection between the charging circuit and the power supply.

[0068] In some embodiments, the first switching module 140 may include a first switch unit, a second switch unit and a pre-charging resistor. The first end of the pre-charging resistor is connected to the input end 130, and the second end of the pre-charging resistor is connected to the first switch unit and the second switch unit respectively.

[0069] That is to say, the first switch unit and the second switch unit in the first switch module 140 share the same pre-charging resistor.

[0070] In one example, the first end of the first switch unit is connected to the input end 130, the second end of the first switch unit is connected to the first output end 100, and the third end of the first switch unit is connected to the second end of the pre-charging resistor. Figure 2 As shown, the first switch unit may include a first switch K1 and a second switch K2. The first switch K1 is connected between the first end of the input terminal 130 and the first output terminal 100, and the second switch K2 is connected between the second end of the pre-charging resistor and the first output terminal 100. The first end of the first switching module 140 and the second end of the first switching module 140 can be connected by controlling the first switch or the second switch to be turned on. When the second switch is turned on and the first switch is turned off, the first switching module can be used to pre-charge the first battery pack. When the first switch is turned on and the second switch is turned off, the first switching module can be used to formally charge the first battery pack.

[0071] In one example, a first end of the second switch unit is connected to the input end 130 , a second end of the second switch unit is connected between the second output end 110 and the first unidirectional switch 120 , and a third end of the second switch unit is connected to the second end of the pre-charging resistor.

[0072] In this example, if Figure 2As shown, the second switch unit may include a third switch K3 and a fourth switch K4. The first end of the third switch K3 is connected to the first end of the input end, the second end of the third switch K3 is connected between the first unidirectional switch 120 and the second output end 110, the first end of the fourth switch K4 is connected to the second end of the pre-charging resistor, and the second end of the fourth switch K4 is connected between the first unidirectional switch 120 and the second output end 110. The first end of the first switching module 140 and the third end of the first switching module 140 can be connected by controlling the third switch K3 or the fourth switch K4 to be turned on. When the fourth switch K4 is turned on and the third switch K3 is turned off, the first switching module 140 can be used to pre-charge the second battery pack. When the third switch K3 is turned on and the fourth switch K4 is turned off, the first switching module 140 can be used to formally charge the second battery pack. Among them, the first unidirectional switch 120 is, for example, a diode D1.

[0073] In this embodiment, under different charging modes, the first switching module can realize both series pre-charging of the battery packs and parallel pre-charging of the battery packs by reusing the same pre-charging resistor, thereby reducing the size of the battery system and reducing the cost.

[0074] In some embodiments, Figure 2 As shown, the second switching module 150 may include a fifth switch K5 and a sixth switch K6. A first end of the fifth switch K5 is connected to a second end of the input terminal 130, and a second end of the fifth switch K5 is connected between the first unidirectional switch 120 and the first output terminal. A first end of the sixth switch K6 is connected to a second end of the input terminal 130, and a second end of the sixth switch K6 is connected to the second output terminal 110.

[0075] In this embodiment, the fifth switch K5 can be turned on and the sixth switch K6 can be turned off to connect the first end of the second switching module 150 and the second end of the second switching module 150. The fifth switch K5 can be turned off and the sixth switch K6 can be turned on to connect the first end of the second switching module 150 and the third end of the second switching module 150.

[0076] In some embodiments, Figure 2 As shown, the charging circuit of the present application may further include a second unidirectional switch D2 , and the second unidirectional switch D2 is connected between the second end of the first switching module 140 and the first output end.

[0077] Alternatively, the charging circuit of the present application may further include a third unidirectional switch D3, a first end of the third unidirectional switch D3 is connected to the third end of the first switching module 140, and a second end of the third unidirectional switch D3 is connected between the second output end and the first unidirectional switch.

[0078] Alternatively, the charging circuit of the present application may further include a fourth unidirectional switch D4 , and the fourth unidirectional switch D4 is connected between the third end of the second switching module 150 and the second output end.

[0079] Alternatively, the charging circuit of the present application may further include a fifth unidirectional switch D5, a first end of the fifth unidirectional switch D5 is connected to the second end of the first switching module 140, and a second end of the fifth unidirectional switch D5 is connected between the first output end and the first unidirectional switch.

[0080] In this embodiment, when the second charging state is that the first output end discharges alone, when the charging circuit of the present application switches from the first charging state to the second charging state, since the fourth unidirectional switch D4 and the first unidirectional switch D1 are provided in the charging circuit, before the switching switch K7 and the sixth switch K6 are disconnected, even if the fifth switch K5 is closed first, no short circuit will be caused.

[0081] In this embodiment, the second switch K2 and the fifth switch K5 can be controlled to be closed first, and then the first switch K1, the switching switch K7 and the sixth switch K6 can be opened. After the pre-charging of the first battery pack BT1 is completed, the first switch K1 is closed. In this way, there is no need to disconnect the charging circuit from the power supply first and then reconnect the charging circuit and the power supply, and seamless switching of the charging mode can be achieved.

[0082] When the second charging state is that the second output end discharges alone, when the charging circuit of the present application switches from the first charging state to the second charging state, since the third unidirectional switch D3 and the first unidirectional switch D1 are provided in the charging circuit, before the first switch K1, the switching switch K7 and the sixth switch K6 are disconnected, even if the third switch K3 or the fourth switch K4 is closed first, no short circuit will be caused.

[0083] In this embodiment, the fourth switch K4 can be controlled to be closed first, and after the pre-charging of the second battery pack BT2 is completed, the third switch K3 is closed, and then the first switch K1, the switching switch K7 and the sixth switch K6 are disconnected. In this way, there is no need to disconnect the charging circuit from the power supply first and then reconnect the charging circuit and the power supply, and seamless switching of the charging mode can be achieved.

[0084] In addition, a first unidirectional switch D1, a second unidirectional switch D2, a third unidirectional switch D3, a fourth unidirectional switch D4, and a fifth unidirectional switch D5 are provided in the charging circuit. Even if the switch components in the charging circuit are sintered, there is no risk of short circuit in the circuit.

[0085] This embodiment can achieve seamless switching of charging modes by adding a unidirectional switch, and there is no risk of short circuit in the circuit even if the switch device is sintered.

[0086] The present application also provides an equalization circuit. Figure 3 to Figure 4 As shown, the balancing circuit may include: a switching module 200 and a switching switch 210. The two ends of the switching module 200 are respectively connected to the first battery pack BT1 and the second battery pack BT2. The switching module 200 is used to balance the voltage of the first battery pack and the second battery pack. The switching module 200 is also used to discharge the first battery pack and / or the second battery pack. The switching switch 210 is connected between the first battery pack BT1 and the second battery pack BT2.

[0087] In one example, the first end of the switching module 200 is connected to the first end of the first battery pack, the second end of the switching module 200 is connected to the first end of the second battery pack, and the second end of the first battery pack is connected to the second end of the second battery pack. The first end and the second end of the first battery pack may be the positive and negative electrodes of the first battery pack, respectively. The first end and the second end of the second battery pack may be the positive and negative electrodes of the second battery pack, respectively.

[0088] In this embodiment, the discharge mode of the battery pack can be switched by controlling the on and off of the switching switch 210. The discharge mode of the battery pack may include the first battery pack and the second battery pack discharging in series, the first battery pack and the second battery pack discharging in parallel, or the first battery pack or the second battery pack discharging alone. When the supply voltage of a single first battery pack or a second battery pack cannot meet the load voltage requirement, the first battery pack BT1 and the second battery pack BT2 may be connected in series to discharge the load. When the supply voltage of a single first battery pack or a second battery pack meets the load voltage requirement, only one battery pack may discharge the load.

[0089] In one example, if Figure 4 As shown, the switch 210 may be a switch K7. The discharge mode of the battery pack is switched by controlling the switch K7 to be turned on and off.

[0090] In one example, the battery pack BT1 and the battery pack BT2 may be connected to each other. Figure 5 The detection device CT shown is used to obtain the SOH (State of Health) of the battery pack. According to the SOH of the battery pack, it is determined which battery pack is used to discharge the load. In this example, the SOH value of the battery pack can be detected regularly to flexibly select the battery pack. In this way, the voltage difference between multiple battery packs can be controlled within a certain range.

[0091] After a long period of use, there will be a voltage difference between multiple battery packs after charging. At this time, it is necessary to perform voltage balancing between multiple battery packs to reduce the voltage difference between multiple battery packs. After charging is completed, the battery system of this embodiment first disconnects from the wired charging pile or the wireless charging transmitting circuit, and then performs voltage balancing between multiple battery packs through the connection switching module. After the voltage balancing is completed, the first battery pack and / or the second battery pack is connected to the output end through the switching module, so that the first battery pack and / or the second battery pack discharges the load.

[0092] In this embodiment, the processes of voltage balancing and discharging of multiple battery packs can be achieved by controlling the switching module, which greatly reduces the volume of the battery system and reduces the cost.

[0093] When the balancing circuit balances the voltage difference between multiple battery packs, the voltage difference between the multiple battery packs will continue to decrease as the balancing duration increases. In the existing solution, the voltage balancing under large voltage difference and the voltage balancing under small voltage difference both use the same solution, which is not conducive to improving the balancing efficiency.

[0094] Based on this, in some embodiments, such as Figure 4 As shown, the switching module 200 may include an eighth switch K8, a ninth switch K9 and a first resistor R2. The eighth switch K8 is connected between the first end of the first battery pack BT1 and the first end of the second battery pack BT2, and the ninth switch K9 and the first resistor R2 are connected in series between the first end of the first battery pack BT1 and the first end of the second battery pack BT2. In other words, the line where the eighth switch K8 is located and the series line of the ninth switch K9 and the first resistor R2 are connected in parallel between the first end of the first battery pack BT1 and the first end of the second battery pack BT2.

[0095] In this embodiment, the voltage difference between the first battery pack and the second battery pack can be determined first. When the voltage difference is greater than the first voltage difference threshold, the eighth switch K8 is controlled to be turned on and the ninth switch K9 is turned off, so as to connect the line where the eighth switch K8 is located, so as to realize voltage balancing at the first set speed. When the voltage difference is less than or equal to the first voltage difference threshold, the eighth switch K8 is controlled to be turned off and the ninth switch K9 is controlled to be turned on, so as to connect the line where the ninth switch K9 is located, so as to realize voltage balancing at the second set speed. It can be understood that the first set speed is greater than the second set speed.

[0096] In this embodiment, after one of the first battery pack and the second battery pack is fully charged, the other of the first battery pack and the second battery pack is charged, and after the other of the first battery pack and the second battery pack is fully charged, the battery system is considered to have completed charging. When the battery system is fully charged, the voltage difference between the first battery pack and the second battery pack is determined. The discharge circuit is controlled to perform voltage balancing between the first battery pack and the second battery pack at a speed that matches the voltage difference.

[0097] In this embodiment, the switching module can also be controlled to connect the ninth switch K9 and the first resistor R2 in series so that the battery pack performs pre-discharge, that is, the battery pack performs pre-discharge to the load. The switching module can also be controlled to connect the eighth switch K8 to the line so that the battery pack performs formal discharge to the load.

[0098] When the battery pack is discharging for the load, the present embodiment first controls the switching module to connect the circuit where the pre-discharge resistor is located to perform pre-discharge, and then controls the switching module to connect the formal discharge circuit after the pre-discharge is completed.

[0099] In this embodiment, the switching module can be controlled to switch between different lines to achieve voltage balancing at different speeds, taking into account both balancing efficiency and balancing accuracy. At the same time, the process of voltage balancing, pre-discharging and formal discharging of multiple battery packs can all be achieved by controlling the switching module, which greatly reduces the volume of the battery system and reduces the cost.

[0100] In some embodiments, Figure 4 As shown, the eighth switch K8, the ninth switch K9 and the first resistor R2 can constitute a first switching module. The switching module can also include a tenth switch K10, an eleventh switch K11 and a second resistor R3. The tenth switch K10, the eleventh switch K11 and the second resistor R3 constitute a second switching module. The first switching module and the second switching module are connected in series to form a switching module 200. The eleventh switch K11 and the second resistor R3 are connected in series and then connected in parallel with the tenth switch K10.

[0101] In this embodiment, the resistance value of the first resistor may be the same as or different from the resistance value of the second resistor.

[0102] When the resistance value of the first resistor is greater than the resistance value of the second resistor, in this embodiment, the voltage difference between the first battery pack and the second battery pack may be determined first.

[0103] When the voltage difference is greater than the first voltage difference threshold, the eighth switch K8 is controlled to be turned on, the ninth switch K9 is turned off, the tenth switch K10 is turned on, and the eleventh switch K11 is turned off, so as to achieve voltage balancing at the first set speed by connecting the lines where the eighth switch K8 and the tenth switch K10 are located.

[0104] When the voltage difference is less than or equal to the first voltage difference threshold and the voltage difference is greater than the second voltage difference threshold, the eighth switch is controlled to be turned on, the ninth switch is turned off, the tenth switch is turned off, and the eleventh switch is turned on, so as to connect the lines where the eighth switch K8 and the eleventh switch K11 are located, so as to achieve voltage balancing at the second set speed.

[0105] When the voltage difference is less than or equal to the second voltage difference threshold, and the voltage difference is greater than the third voltage difference threshold, the eighth switch is controlled to be turned off, the ninth switch is turned on, the tenth switch is turned on, and the eleventh switch is turned off, so as to connect the lines where the ninth switch K9 and the tenth switch K10 are located, so as to realize voltage balancing at the third set speed. The first voltage difference threshold is greater than the second voltage difference threshold, and the second voltage difference threshold is greater than the third voltage difference threshold.

[0106] When the voltage difference is less than or equal to the third voltage difference threshold, the eighth switch is controlled to be turned off, the ninth switch is turned on, the tenth switch is turned off, and the eleventh switch is turned on, so as to achieve voltage balancing at a fourth set speed by connecting the lines where the ninth switch K9 and the eleventh switch K11 are located.

[0107] When the resistance of the first resistor is equal to the resistance of the second resistor, in this embodiment, when the voltage difference is greater than the first voltage difference threshold and when the voltage difference is less than or equal to the third voltage difference threshold, the control method of the balancing circuit is the same and will not be described here.

[0108] When the voltage difference is less than or equal to the first voltage difference threshold, and the voltage difference is greater than the third voltage difference threshold, the eighth switch and the eleventh switch are controlled to be turned on and the ninth switch and the tenth switch are turned off, or the eighth switch and the eleventh switch are turned off and the ninth switch and the tenth switch are turned on, so as to connect the line where the ninth switch K9 and the tenth switch K10 are located or connect the line where the eighth switch K8 and the eleventh switch K11 are located, so as to realize voltage balancing at the second set speed. The first voltage difference threshold is greater than the third voltage difference threshold.

[0109] It can be understood that the first set speed, the second set speed, the third set speed, and the fourth set speed gradually decrease.

[0110] As an example, the present embodiment can detect the voltage difference between multiple battery packs in real time or at a fixed time. When it is detected that the voltage difference is greater than the first voltage difference threshold, the eighth switch is first controlled to be turned on, the ninth switch is turned off, the tenth switch is turned on, and the eleventh switch is turned off to perform fast balancing. After a period of fast balancing, the voltage difference decreases. When it is detected that the voltage difference is less than or equal to the first voltage difference threshold, and the voltage difference is greater than the second voltage difference threshold, the eighth switch is controlled to be turned on, the ninth switch is turned off, the tenth switch is turned off, and the eleventh switch is turned on to perform medium-speed balancing. When it is detected that the voltage difference is less than or equal to the second voltage difference threshold, and the voltage difference is greater than the third voltage difference threshold, the eighth switch is controlled to be turned off, the ninth switch is turned on, the tenth switch is turned on, and the eleventh switch is turned off to further reduce the balancing speed. Finally, when the voltage difference is less than or equal to the third voltage difference threshold, the eighth switch is controlled to be turned off, the ninth switch is turned on, the tenth switch is turned off, and the eleventh switch is turned on to perform slow balancing. In this way, the efficiency of voltage balancing can be improved by flexibly adjusting the lines selected by the switching module. Furthermore, when the voltage difference is less than or equal to the third voltage difference threshold, slow balancing is adopted to improve the accuracy of balancing.

[0111] This embodiment uses two switching modules to flexibly change the effective circuit of the switching module according to the different voltage differences of the battery pack. In addition, for different battery pack voltage differences, the voltage of the battery pack can be balanced at different speeds, thereby achieving a better balance between the balancing speed and accuracy.

[0112] In this embodiment, more switching modules can be provided according to actual needs. The resistance values ​​of resistors in different switching modules can be different, so as to achieve a more refined voltage difference level.

[0113] In some embodiments, the balancing circuit may further include an output terminal. The third terminal of the switching module is also used to connect to the output terminal, and the output terminal is used to discharge the load.

[0114] As an example, Figure 4 As shown, the output terminal may include a first output terminal A and a second output terminal B. The first output terminal A and the second output terminal B are both connected to a load.

[0115] In this embodiment, all switching devices in the battery system may be contactors.

[0116] In the battery system of this embodiment, the number of battery packs may be greater than two.

[0117] In this embodiment, the unidirectional switch can be replaced by any circuit, device or apparatus for realizing unidirectional conduction of current. For example, the unidirectional switch can be a diode.

[0118] In this embodiment, the pre-charging resistor of the charging circuit and the resistor in the switching module of the equalizing circuit are used to reduce the current at both ends of the contactor before it is closed, so as to prevent the contactor from sintering due to excessive current when the contactor is closed. It can be extended to any circuit, component, device, equipment, etc. that can reduce the current at both ends of the contactor and prevent sintering when it is closed.

[0119] The embodiment of the present application can integrate the charging circuit and the balancing circuit together. As an example, Figure 5 The specific circuit structure can refer to the specific embodiments of the above-mentioned charging circuit and equalizing circuit, which will not be described in detail here.

[0120] An embodiment of the present application also provides a charging system, comprising a charging circuit as described in any one of the above embodiments.

[0121] An embodiment of the present application further provides a battery system, comprising a balancing circuit as described in any one of the above embodiments, a first battery pack, and a second battery pack.

[0122] The present application also provides an electricity system, such as Figure 6 As shown, the power system 2000 includes the battery system 1000 and the load 1100 as described in the above embodiment.

[0123] An embodiment of the present application also provides a vehicle, comprising the system as described in the above embodiment.

[0124] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein. The scope of the present application is defined by the appended claims.

Claims

1. A charging circuit, characterized in that: include: a first output terminal, a second output terminal, a first unidirectional switch, and a switching switch, The switch is connected between the first output terminal and the second output terminal; The first unidirectional switch is connected to the first output end and the second output end respectively, and is used for unidirectional conduction between the first output end and the second output end. The first output end is used to connect to a first battery pack, and the second output end is used to connect to a second battery pack.

2. The charging circuit according to claim 1, characterized in that: It also includes an input terminal, a first switching module and a second switching module, The first end of the first switching module is connected to the first end of the input end, the second end of the first switching module is connected to the first output end, and the third end of the first switching module is connected between the first unidirectional switch and the second output end; The first end of the second switching module is connected to the second end of the input end, the second end of the second switching module is connected between the first unidirectional switch and the first output end, and the third end of the second switching module is connected to the second output end.

3. The charging circuit according to claim 2, characterized in that: The first switching module includes a first switch unit, a second switch unit and a pre-charging resistor. The first end of the pre-filling resistor is connected to the input end, and the second end of the pre-filling resistor is connected to the first switch unit and the second switch unit respectively; A first end of the first switch unit is connected to the input end, a second end of the first switch unit is connected to the first output end, and a third end of the first switch unit is connected to the second end of the pre-charging resistor; A first end of the second switch unit is connected to the input end, a second end of the second switch unit is connected between the second output end and the first unidirectional switch, and a third end of the second switch unit is connected to the second end of the pre-charging resistor.

4. The charging circuit according to claim 3, characterized in that: The first switch unit includes a first switch and a second switch, the first switch is connected between the first end of the input end and the first output end, and the second switch is connected between the second end of the pre-charging resistor and the first output end.

5. The charging circuit according to claim 3, characterized in that: The second switch unit includes a third switch and a fourth switch, wherein a first end of the third switch is connected to a first end of the input end, a second end of the third switch is connected between the first unidirectional switch and the second output end, a first end of the fourth switch is connected to a second end of the pre-charging resistor, and a second end of the fourth switch is connected between the first unidirectional switch and the second output end.

6. The charging circuit according to claim 2, characterized in that: The second switching module includes a fifth switch and a sixth switch; A first end of the fifth switch is connected to a second end of the input end, and a second end of the fifth switch is connected between the first unidirectional switch and the first output end; A first end of the sixth switch is connected to a second end of the input end, and a second end of the sixth switch is connected to the second output end.

7. The charging circuit according to any one of claims 1 to 6, characterized in that: The charging circuit further includes a second unidirectional switch connected between the second end of the first switching module and the first output end; or, The charging circuit further includes a third unidirectional switch, a first end of the third unidirectional switch is connected to the third end of the first switching module, and a second end of the third unidirectional switch is connected between the second output end and the first unidirectional switch; or, The charging circuit further includes a fourth unidirectional switch connected between the third terminal of the second switching module and the second output terminal; or, The charging circuit further includes a fifth unidirectional switch, a first end of the fifth unidirectional switch is connected to the second end of the first switching module, and a second end of the fifth unidirectional switch is connected between the first output end and the first unidirectional switch.

8. An equalizing circuit, characterized in that: include: Switching modules and toggle switches, The two ends of the switching module are respectively connected to the first battery pack and the second battery pack, and the switching module is used to perform voltage balancing on the first battery pack and the second battery pack; the switching module is also used to discharge the first battery pack and / or the second battery pack; The switch is connected between the first battery pack and the second battery pack.

9. The equalizing circuit according to claim 8, characterized in that: The first end of the switching module is connected to the first end of the first battery pack, the second end of the switching module is connected to the first end of the second battery pack, and the second end of the first battery pack is connected to the second end of the second battery pack.

10. The equalizing circuit according to claim 9, characterized in that: The switching module includes an eighth switch, a ninth switch and a first resistor, the eighth switch is connected between the first end of the first battery pack and the first end of the second battery pack, and the ninth switch and the first resistor are connected in series between the first end of the first battery pack and the first end of the second battery pack.

11. The equalizing circuit according to claim 10, characterized in that: The switching module further includes a tenth switch, an eleventh switch and a second resistor, wherein the eleventh switch and the second resistor are connected in series and then connected in parallel with the tenth switch; The eighth switch, the ninth switch and the first resistor constitute a first switching module, the tenth switch, the eleventh switch and the second resistor constitute a second switching module, and the first switching module and the second switching module are connected in series to constitute the switching module.

12. The equalizing circuit according to claim 11, characterized in that: The first resistor is greater than the second resistor.

13. The equalizing circuit according to claim 8, characterized in that: It also includes an output end, and the third end of the switching module is also used to connect to the output end, and the output end is used to discharge the load.

14. A charging system, characterized in that: The charging circuit comprises the charging circuit as claimed in any one of claims 1 to 7.

15. A battery system, characterized in that: The invention comprises the equalizing circuit as claimed in any one of claims 8 to 13, a first battery pack and a second battery pack.

16. An electricity system, characterized in that: The invention comprises the battery system as claimed in claim 15 and a load.

17. A vehicle, characterized in that: Comprising a system as claimed in any one of claims 14 to 16.

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