Battery circuit and vehicle

Abstract

Battery circuit and vehicle. The circuit includes a power supply end, a first battery pack, a second battery pack, a voltage transformation unit, a first switch, a second switch, a ground end, and a control unit. The positive electrode of the first battery pack is connected to the power supply end, the negative electrode of the first battery pack is connected to the positive electrode of the second battery pack, the negative electrode of the second battery pack is connected to the ground end, the first end of the first switch is connected to the power supply end, the second end of the first switch is connected to the first end of the second switch, the control terminal of the first switch is connected to the first output end of the control unit, the second end of the second switch is connected to the ground end, the control terminal of the second switch is connected to the second output end of the control unit, the voltage transformation unit is connected between the negative electrode of the first battery pack and the second end of the first switch, and controls to connect or disconnect the first switch and the second switch according to at least one of the temperature of the first battery pack and the second battery pack and the temperature of the second battery pack.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority to Chinese Patent Application No. 202210611784.6, entitled "BATTERY CIRCUIT AND VEHICLE," filed on May 31, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the field of vehicle technology, and more particularly to battery circuits and vehicles. [Background technology]

[0003] In the prior art, a dual battery pack is provided, which consists of a power battery pack and an energy battery pack.

[0004] Temperature is an important parameter of batteries, and how to control the temperature of a dual battery pack consisting of a power battery pack and an energy battery pack has become a technical problem that needs to be solved quickly. Summary of the Invention [Means for solving the problem]

[0005] The present disclosure is intended to provide a novel technical solution for battery circuits.

[0006] According to a first aspect of the present disclosure, there is provided a battery circuit including a power terminal, a first battery pack, a second battery pack of a different type from the first battery pack, a transformer unit, a first switch, a second switch, a ground terminal, and a control unit.

[0007] The positive electrode of the first battery pack is connected to a power supply terminal, and the negative electrode of the first battery pack is connected to the positive electrode of the second battery pack.

[0008] The negative terminal of the second battery pack is connected to the ground terminal.

[0009] A first terminal of the first switch is connected to the power supply terminal, a second terminal of the first switch is connected to the first terminal of the second switch, and a control terminal of the first switch is connected to the first output terminal of the control unit.

[0010] A second terminal of the second switch is connected to the ground terminal, and a control terminal of the second switch is connected to the second output terminal of the control unit.

[0011] A transformer unit is connected between the negative terminal of the first battery pack and the second terminal of the first switch.

[0012] The control unit is configured to control the first switch and the second switch to close or open according to at least one of the temperatures of the first battery pack and the second battery pack and the temperature of the second battery pack.

[0013] According to one embodiment of the present disclosure, the control unit comprises: controlling the first switch and the second switch to be closed or opened according to a first preset control rule when any one of an average temperature of the first battery pack and the second battery pack, the highest temperature of the temperatures of the first battery pack and the second battery pack, the temperature of the first battery pack, or the temperature of the second battery pack is below a preset temperature, so as to bring the first battery pack and the second battery pack into a state of charging each other; In order to bring the first battery pack and the second battery pack into a state other than a charging state, when either the average temperature of the first battery pack and the second battery pack, the highest temperature among the temperatures of the first battery pack and the second battery pack, the temperature of the first battery pack, or the temperature of the second battery pack is equal to or higher than a preset temperature, the control unit is configured to control the first switch and the second switch to close or open in accordance with a second preset control rule.

[0014] According to an embodiment of the present disclosure, the deviation between the rated voltage of the first battery pack and the rated voltage of the second battery pack is less than a first preset range; and / or The deviation between the ratio of the capacity of the first battery pack to the capacity of the second battery pack and the ratio of the maximum discharge rate of the second battery pack to the maximum discharge rate of the first battery pack is less than a second preset range.

[0015] According to one embodiment of the present disclosure, the rated voltage of the first battery pack is the same as the rated voltage of the second battery pack; and / or the ratio of the capacity of the first battery pack to the capacity of the second battery pack is the same as the ratio of the maximum discharge rate of the second battery pack to the maximum discharge rate of the first battery pack;

[0016] According to one embodiment of the present disclosure, the first battery pack is a power-type battery pack and the second battery pack is an energy-type battery pack; or The first battery pack is an energy-type battery pack, and the second battery pack is a power-type battery pack.

[0017] According to one embodiment of the present disclosure, the control unit includes a subtractor, a control subunit, a pulse width modulation (PWM) signal generating subunit, and an inverter.

[0018] A first input terminal of the subtractor is configured to receive the current value of the first battery pack, a second input terminal of the subtractor is configured to receive the reference current value, and an output terminal of the subtractor is connected to an input terminal of the control subunit.

[0019] A first output terminal of the control sub-unit is connected to an input terminal of the PWM signal generating sub-unit.

[0020] A first output terminal of the PWM signal generating subunit is connected to the control terminal of the first switch, and a second output terminal of the PWM signal generating subunit is connected to the input terminal of the inverter.

[0021] The output terminal of the inverter is connected to the control terminal of the second switch.

[0022] According to one embodiment of the present disclosure, the first battery pack is a power-type battery pack and the second battery pack is an energy-type battery pack. The battery circuit further includes a filter unit.

[0023] A first terminal of the filter unit is connected to the positive electrode of the first battery pack, a second terminal of the filter unit is connected to the power supply terminal, and a third terminal of the filter unit is connected to the negative electrode of the first battery pack.

[0024] According to one embodiment of the present disclosure, a filter unit includes a first inductor and a first capacitor.

[0025] A first terminal of the first inductor is connected to the positive electrode of the first battery pack, and a second terminal of the first inductor is connected to the power supply terminal.

[0026] A first terminal of the first capacitor is connected to the first terminal of the first inductor, and a second terminal of the first capacitor is connected to the negative electrode of the first battery pack.

[0027] According to one embodiment of the present disclosure, the battery circuit further includes a first reflux unit and a second reflux unit.

[0028] The input terminal of the first freewheeling unit is connected to the second terminal of the first switch, and the output terminal of the first freewheeling unit is connected to the first terminal of the first switch.

[0029] The input terminal of the second freewheeling unit is connected to the second terminal of the second switch, and the output terminal of the second freewheeling unit is connected to the first terminal of the second switch.

[0030] According to one embodiment of the present disclosure, the first freewheeling unit is a first diode and the second freewheeling unit is a second diode.

[0031] The anode of the first diode is connected to the second terminal of the first switch, and the cathode of the first diode is connected to the first terminal of the first switch.

[0032] The anode of the second diode is connected to the second terminal of the second switch, and the cathode of the second diode is connected to the first terminal of the second switch.

[0033] According to one embodiment of the present disclosure, the battery circuit further includes a voltage stabilization unit.

[0034] The voltage stabilizing unit is connected between the power supply terminal and the ground terminal.

[0035] According to one embodiment of the present disclosure, the voltage stabilization unit is a second capacitor.

[0036] According to one embodiment of the present disclosure, the transformer unit is a second inductor.

[0037] According to a second aspect of the present disclosure, there is provided a vehicle including the battery circuit of any of the implementations of the first aspect described above.

[0038] The battery circuit provided in one embodiment of the present disclosure can control the self-heating of a dual battery pack consisting of a first battery pack and a second battery pack according to the temperature of the batteries.

[0039] Other features and advantages of the present disclosure will become apparent from the following detailed description of illustrative embodiments of the present disclosure, which is provided with reference to the drawings.

[0040] The drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the disclosure. [Brief explanation of the drawings]

[0041] [Figure 1] 1 is a schematic structural diagram I of a battery circuit according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic structural diagram of a control unit according to an embodiment of the present disclosure. [Figure 3] FIG. 4 is a simulated operating current diagram of a first battery pack and a second battery pack according to one embodiment of the present disclosure. [Figure 4] 2 is a schematic structural diagram II of a battery circuit according to an embodiment of the present disclosure. [Figure 5] 3 is a schematic structural diagram III of a battery circuit according to an embodiment of the present disclosure. [Explanation of symbols]

[0042] 100 battery circuit 101 Power terminal 102 First Battery Pack 103 Second Battery Pack 104 Transformer Unit 1041 Second Inductor 105 First Switch 106 Second Switch 107 Ground terminal 108 Control Unit 1081 Subtractor 1082 Control Subunit 1083 Pulse Width Modulation (PWM) Signal Generation Subunit 1084 inverter 1085 Switch Open Signal Generation Subunit 109 Filter Unit 1091 First Inductor 1092 First Capacitor 110 First reflux unit 1101 First diode 111 Second reflux unit 1111 Second diode 112 Voltage Stabilizer Unit 1121 Second Capacitor DETAILED DESCRIPTION OF THE INVENTION

[0043] Various exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. It should be noted that the relative arrangements of components and steps, formulas and numerical values ​​described in the embodiments do not limit the scope of the present disclosure unless otherwise specified.

[0044] The following description of at least one exemplary embodiment is intended to be merely illustrative and is not intended to constitute any limitation on the disclosure and its application or uses.

[0045] Techniques, methods and devices known to those skilled in the art may not be described in detail, but where appropriate, the techniques, methods and devices should be considered part of this specification.

[0046] In the examples shown and described herein, any particular values ​​should be construed as merely illustrative and not limiting, and thus other examples of the exemplary embodiments may have different values.

[0047] It should be noted that in the following figures, like numerals and letters refer to like things, so once something is defined in a figure, it need not be further explained in subsequent figures.

[0048] One embodiment of the present disclosure provides a battery circuit 100. As shown in Fig. 1, the battery circuit 100 includes a power supply terminal 101, a first battery pack 102, a second battery pack 103 of a different type from the first battery pack 102, a transformer unit 104, a first switch 105, a second switch 106, a ground terminal 107, and a control unit 108.

[0049] The positive electrode of the first battery pack 102 is connected to the power supply terminal 101. The negative electrode of the first battery pack 102 is connected to the positive electrode of the second battery pack 103.

[0050] The negative electrode of the second battery pack 103 is connected to the ground terminal 107 .

[0051] A first terminal of the first switch 105 is connected to the power supply terminal 101. A second terminal of the first switch 105 is connected to a first terminal of the second switch 106. A control terminal of the first switch 105 is connected to a first output terminal of the control unit 108.

[0052] A second terminal of the second switch 106 is connected to the ground terminal 107. A control terminal of the second switch 106 is connected to a second output terminal of the control unit 108.

[0053] The transformer unit 104 is connected between the negative terminal of the first battery pack 102 and a second terminal of the first switch 105 .

[0054] The control unit 108 is configured to control the first switch 105 and the second switch 106 to close or open according to at least one of the temperature of the first battery pack 102 and the temperature of the second battery pack 103.

[0055] This embodiment of the present disclosure provides a battery circuit including a power supply terminal, a first battery pack, a second battery pack of a different type from the first battery pack, a transformer unit, a first switch, a second switch, a ground terminal, and a control unit. The positive terminal of the first battery pack is connected to the power supply terminal. The negative terminal of the first battery pack is connected to the positive terminal of the second battery pack. The negative terminal of the second battery pack is connected to the ground terminal. The first terminal of the first switch is connected to the power supply terminal. The second terminal of the first switch is connected to the first terminal of the second switch. The control terminal of the first switch is connected to a first output terminal of the control unit. The second terminal of the second switch is connected to the ground terminal. The control terminal of the second switch is connected to a second output terminal of the control unit. The transformer unit is connected between the negative terminal of the first battery pack and the second terminal of the first switch. The control unit is configured to control the first switch and the second switch to close or open according to at least one of the temperatures of the first battery pack and the second battery pack and the temperature of the second battery pack, so that self-heating of the dual battery pack consisting of the first battery pack and the second battery pack can be controlled according to the battery temperature.

[0056] In this embodiment of the present disclosure, when the battery circuit 100 is in a discharge state, the power terminal 101 in the battery circuit 100 is configured to connect to the power input terminal of the load, and the ground terminal 107 in the battery circuit 100 is configured to connect to the ground terminal of the load. Illustratively, the load may be a motor in an electric or hybrid vehicle.

[0057] Alternatively, when the battery circuit 100 is in a charging state, the power terminal 101 in the battery circuit 100 is configured to connect to a power output terminal of a charging device, and the ground terminal 107 in the battery circuit 100 is configured to connect to a ground terminal of the charging device. Illustratively, the charging device may be a charging pile or braking system of an electric or hybrid vehicle.

[0058] In one embodiment of the present disclosure, as shown in Figure 4, the transformer unit 104 may be a second inductor 1041. Of course, the transformer unit 104 may be implemented in other ways.

[0059] In one embodiment of the present disclosure, the inductance value of the second inductor 1041 may be set in the range of 2 μH to 1500 μH.

[0060] In this embodiment of the present disclosure, when the transformer unit 104 is the second inductor 1041, the transformer unit 104 has a low cost and a simple structure.

[0061] In one embodiment of the present disclosure, the first switch 105 and the second switch 106 may be switch devices such as a switch IC, a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), or a silicon carbide (SiC) switch.

[0062] It should be noted that in this embodiment of the present disclosure, the first switch 105 and the second switch 106 are the same type of switch. Specifically, when the control terminals of the first switch and the second switch receive a high level, the first switch 105 and the second switch 106 are both closed or open. When the control terminals of the first switch and the second switch receive a low level, the first switch 105 and the second switch 106 are both open or closed.

[0063] In this embodiment of the present disclosure, the first battery pack 102 and the second battery pack 103 are of different types. Specifically, the first battery pack 102 is a powered battery pack and the second battery pack 103 is an energy-based battery pack. Alternatively, the first battery pack 102 is an energy-based battery pack and the second battery pack 103 is a powered battery pack.

[0064] In this embodiment of the present disclosure, the powered battery pack is a high power density battery pack. Power density is the maximum energy transfer power during charging / discharging of a battery per unit weight or unit volume. Also, in this embodiment of the present disclosure, the voltage value of the powered battery pack may be set in the range of 100V to 1000V.

[0065] The energy-type battery pack is a battery pack with a high energy density. Energy density is the energy stored in a battery per unit weight or volume. In this embodiment of the present disclosure, the voltage value of the energy-type battery pack may be set in the range of 100V to 1000V.

[0066] This embodiment of the present disclosure does not limit the specific types of the first battery pack 102 and the second battery pack 103, which can improve the compatibility of the battery circuit 100 provided in the embodiment of the present disclosure.

[0067] In this embodiment of the present disclosure, the control unit 108 being configured to control the first switch 105 and the second switch 106 to close or open according to at least one of the temperature of the first battery pack 102 and the temperature of the second battery pack 103 may be specifically implemented in the following two ways:

[0068] First aspect: The first switch 105 and the second switch 106 are controlled to close or open according to a first preset control rule when either the average temperature of the first battery pack 102 and the second battery pack 103, the highest temperature among the temperatures of the first battery pack 102 and the second battery pack 103, the temperature of the first battery pack 102, or the temperature of the second battery pack 103 is below a preset temperature, in order to put the first battery pack 102 and the second battery pack 103 into a state of charging each other.

[0069] In this embodiment of the present disclosure, the temperature of the first battery pack 102 is typically similar to the temperature of the second battery pack 103. Therefore, the temperature of either the first battery pack 102 or the second battery pack 103, the average temperature of the first battery pack and the second battery pack, or the highest temperature of the first battery pack and the second battery pack may represent the temperature of the dual battery pack consisting of the first battery pack 102 and the second battery pack 103.

[0070] In one example, a temperature coefficient may be used to calculate the temperature of the first battery pack 102 according to the resistance value of the internal resistance in the first battery pack 102. Similarly, a temperature coefficient may be used to calculate the temperature of the second battery pack 103 according to the resistance value of the internal resistance in the second battery pack 103.

[0071] It should be noted that in this embodiment of the present disclosure, the method of the control unit 108 obtaining the temperature of the first battery pack 102 and the temperature of the second battery pack 103 is not limited.

[0072] In this embodiment of the present disclosure, the preset temperature is the lowest temperature at which the battery packs can operate stably. When the temperature of either the second battery pack 102 or the second battery pack 103, the average temperature of the second battery pack and the second battery pack, or the highest temperature of the second battery pack and the second battery pack is below the preset temperature, it indicates that the first battery pack 102 or the second battery pack 103 cannot operate stably.

[0073] In one example, the preset temperature may be set to -10°C.

[0074] In this embodiment of the present disclosure, the first preset control rule may be to control the first battery pack 102 to discharge in order to charge the second battery pack 103 within a first time period, and to control the second battery pack 103 to discharge in order to charge the first battery pack 102 within a second time period. The second time period is adjacent to the first time period and is a time period before or after the first time period. The periods corresponding to the first time period and the second time period are the same, which may be set according to experience.

[0075] Based on the above, the first preset control rule implements an on / off operation, which includes controlling the first switch 105 to close and the second switch 106 to open within a first sub-time period, controlling the first switch 105 to open and the second switch 106 to close within a second sub-time period, controlling the first switch 105 to open and the second switch 106 to close within a third sub-time period, and controlling the first switch 105 to close and the second switch 106 to open within a fourth sub-time period. The on / off operation is repeated.

[0076] The second sub-time period is adjacent to the first sub-time period and follows the first sub-time period. The durations corresponding to the first sub-time period and the second sub-time period may be set empirically. Furthermore, the first sub-time period and the second sub-time period form the first time period.

[0077] Correspondingly, the fourth sub-time period is adjacent to and follows the third sub-time period. The periods corresponding to the third sub-time period and the fourth sub-time period may be set empirically. Furthermore, the third sub-time period and the fourth sub-time period form a second time period.

[0078] In this embodiment of the present disclosure, during the first sub-time period, the first switch 105 is controlled to close and the second switch 106 is controlled to open. In this case, the first battery pack 102 charges the transformer unit 104. During the second sub-time period, the first switch 105 is controlled to open and the second switch 106 is controlled to close. In this case, the transformer unit 104 releases the stored power to the second battery pack 103. That is, the transformer unit 104 implements a boost function. This allows the first battery pack 102 to charge the second battery pack 103.

[0079] During the third sub-time period, the first switch 105 is controlled to open, and the second switch 106 is controlled to close. In this case, the second battery pack 103 charges the transformer unit 104. During the fourth sub-time period, the first switch 105 is controlled to close, and the second switch 106 is controlled to open. In this case, the transformer unit 104 releases the stored power to the first battery pack 102. That is, the transformer unit 104 implements a boost function. This allows the second battery pack 103 to charge the first battery pack 102.

[0080] In this embodiment, the internal resistances of the first battery pack 102 and the second battery pack 103 can cause the temperatures of the first battery pack 102 and the second battery pack 103 to rise above a preset temperature due to self-heating while charging each other. When the temperatures of the first battery pack 102 and the second battery pack 103 rise above the preset temperature due to self-heating, the first battery pack 102 and the second battery pack 103 can operate stably.

[0081] Second aspect: The first switch 105 and the second switch 106 are controlled to close or open according to a second preset control rule when either the average temperature of the first battery pack 102 and the second battery pack 103, the highest temperature among the temperatures of the first battery pack 102 and the second battery pack 103, the temperature of the first battery pack 102, or the temperature of the second battery pack 103 is equal to or higher than a preset temperature, in order to put the first battery pack 102 and the second battery pack 103 into a state other than a charging state.

[0082] In this embodiment of the present disclosure, the second preset control rule is a rule different from the first preset control rule. In one example, the second preset control rule may be to control both the first switch 105 and the second switch 106 to be open.

[0083] In this embodiment of the present disclosure, when the average temperature of the first battery pack 102 and the second battery pack 103, the highest temperature among the temperatures of the first battery pack 102 and the second battery pack 103, the temperature of the first battery pack 102, or the temperature of the second battery pack 103 is equal to or higher than a preset temperature, it indicates that the first battery pack 102 and the second battery pack 103 can operate stably. In this case, the first switch 105 and the second switch 106 are controlled to close or open according to a second preset control rule so that the first battery pack 102 and the second battery pack 103 are in a state other than a charging state, i.e., a state in which they do not self-heat. For example, to connect the first battery pack 102 and the second battery pack 103 in series and discharge them, both the first switch 105 and the second switch 106 are controlled to open.

[0084] This embodiment of the present disclosure provides a battery circuit including a power supply terminal, a first battery pack, a second battery pack of a different type from the first battery pack, a transformer unit, a first switch, a second switch, a ground terminal, and a control unit. The positive terminal of the first battery pack is connected to the power supply terminal. The negative terminal of the first battery pack is connected to the positive terminal of the second battery pack. The negative terminal of the second battery pack is connected to the ground terminal. The first terminal of the first switch is connected to the power supply terminal. The second terminal of the first switch is connected to the first terminal of the second switch. The control terminal of the first switch is connected to a first output terminal of the control unit. The second terminal of the second switch is connected to the ground terminal. The control terminal of the second switch is connected to a second output terminal of the control unit. The transformer unit is connected between the negative terminal of the first battery pack and the second terminal of the first switch. The control unit is configured to control the first switch and the second switch to close or open according to at least one of the temperatures of the first battery pack and the second battery pack and the temperature of the second battery pack, so that self-heating of the dual battery pack consisting of the first battery pack and the second battery pack can be controlled according to the battery temperature.

[0085] In this embodiment of the present disclosure, the deviation between the rated voltage U1 of the first battery pack 102 and the rated voltage U2 of the second battery pack 103 is less than a first preset range.

[0086] In this embodiment of the present disclosure, the first preset range is an allowable range of deviation between the rated voltage U1 of the first battery pack 102 and the rated voltage U3 of the second battery pack 103. When the deviation between the rated voltage U1 of the first battery pack 102 and the rated voltage U2 of the second battery pack 103 is less than the first preset range, it indicates that the rated voltage U1 of the first battery pack 102 is substantially the same as the rated voltage U2 of the second battery pack 103.

[0087] In one embodiment of the present disclosure, the first preset range may be, for example, 0.2*U1 or 0.2*U2. When the first preset range is 0.2*U1, 1.2*U1≧U2≧0.8*U1. When the first preset range is 0.2*U2, 1.2*U2≧U1≧0.8*U2.

[0088] It should be noted that in this embodiment of the present disclosure, the specific value of the first preset range is not limited.

[0089] In this embodiment of the present disclosure, when the deviation between the rated voltage U1 of the first battery pack 102 and the rated voltage U2 of the second battery pack 103 is less than a first preset range, efficient energy transfer can be achieved between the first battery pack 102 and the second battery pack 103. For example, efficient mutual charging can be achieved between the first battery pack 102 and the second battery pack 103.

[0090] It should be noted that in general, the sum of the rated voltage U1 of the first battery pack 102 and the rated voltage U1 of the second battery pack 103 is equal to the total voltage Uout required by the load, i.e., U1+U2=Uout.

[0091] In one embodiment of the present disclosure, the rated voltage U1 of the first battery pack 102 is the same as the rated voltage U2 of the second battery pack 103. This allows for the most efficient energy transfer between the first battery pack 102 and the second battery pack 103.

[0092] Based on the above, in one example, Uout = 550V. In this case, you may set U1 = U2 = 275V.

[0093] In this embodiment of the present disclosure, the deviation between the ratio of the capacity Q1 of the first battery pack 102 to the capacity Q2 of the second battery pack 103 and the ratio of the maximum discharge rate X2 of the second battery pack 103 to the maximum discharge rate X1 of the first battery pack 102 is less than a second preset range.

[0094] The maximum discharge rate is the ratio of the maximum discharge current of a battery pack to the battery capacity. For example, if a battery pack has a battery capacity of 10 Ah and a maximum discharge current of 50 A, the maximum discharge rate is 50 A / 10 Ah = 5 C.

[0095] In this embodiment of the present disclosure, the second preset range is an allowable range of deviation between the ratio of the capacity Q1 of the first battery pack 102 to the capacity Q2 of the second battery pack 103 and the ratio of the maximum discharge rate X2 of the second battery pack 103 to the maximum discharge rate X1 of the first battery pack 102. When the deviation between the ratio of the capacity Q1 of the first battery pack 102 to the capacity Q2 of the second battery pack 103 and the ratio of the maximum discharge rate X2 of the second battery pack 103 to the maximum discharge rate X1 of the first battery pack 102 is less than the second preset range, it indicates that the ratio of the capacity Q1 of the first battery pack 102 to the capacity Q2 of the second battery pack 103 is substantially the same as the ratio of the maximum discharge rate X2 of the second battery pack 103 to the maximum discharge rate X1 of the first battery pack 102.

[0096] In one embodiment of the present disclosure, the second preset range may illustratively be ±0.5.

[0097] It should be noted that in this embodiment of the present disclosure, the specific value of the second preset range is not limited.

[0098] In this embodiment of the present disclosure, when the deviation between the ratio of the capacity of the first battery pack 102 to the capacity of the second battery pack 103 and the ratio of the maximum discharge rate of the second battery pack 103 to the maximum discharge rate of the first battery pack 101 is less than a second preset range, the maximum discharge currents of the two battery packs can be substantially the same. Based on the above, for example, two battery packs can be connected in series for stable discharge.

[0099] It should be noted that in general, the sum of the capacity Q1 of the first battery pack 102 and the capacity Q2 of the second battery pack 103 is equal to the total capacity Qnom required by the load, ie, Q1+Q2=Qnom.

[0100] In one embodiment of the present disclosure, the ratio of the capacity Q1 of the first battery pack 102 to the capacity Q2 of the second battery pack 103 is the same as the ratio of the maximum discharge rate X2 of the second battery pack 103 to the maximum discharge rate X1 of the first battery pack 102. This allows the maximum discharge currents of the two battery packs to be exactly the same.

[0101] Based on the above, in one example, Qnom = 120Ah. In this case, we may set Q1 = 100Ah, Q2 = 20Ah, X1 = 1C, and X2 = 5C.

[0102] In one embodiment of the present disclosure, the control unit 108 may control the first switch 105 and the second switch 106 to close or open according to a first preset control law via a pulse width modulation (PWM) signal. The first switch 105 and the second switch 106 are controlled to open and close according to the PWM signal. The open and closed periods of the first switch 105 and the second switch 106 are controlled according to the duty cycle of the PWM signal.

[0103] In one embodiment of the present disclosure, to implement the aforementioned PWM signal, as shown in FIG. 2, the control unit 108 includes a subtractor 1081, a control subunit 1082, a PWM signal generating subunit 1083, and an inverter 1084.

[0104] A first input terminal of the subtractor 1081 is configured to receive the current value of the first battery pack 102. A second input terminal of the subtractor 1081 is configured to receive the reference current value. An output terminal of the subtractor 1081 is connected to an input terminal of the control subunit 1082.

[0105] A first output terminal of the control sub-unit 1082 is connected to an input terminal of the PWM signal generating sub-unit 1083 .

[0106] A first output terminal of the PWM signal generating subunit 1083 is connected to a control terminal of the first switch 105. A second output terminal of the PWM signal generating subunit 1083 is connected to an input terminal of an inverter 1084.

[0107] The output terminal of the inverter 1084 is connected to the control terminal of the second switch 106 .

[0108] In this embodiment of the present disclosure, the control subunit 1082 stores the preset temperature. The control subunit 108 is configured to obtain the average temperature of the temperature of the first battery pack 105 and the temperature of the second battery pack 106, the highest temperature of the temperature of the first battery pack 105 and the temperature of the second battery pack 106, the temperature of the first battery pack 102, or the temperature of the second battery pack 103.

[0109] In one embodiment of the present disclosure, the control subunit 1082 may illustratively be a microcontroller unit (MCU), a central processing unit (CPU), or the like.

[0110] In this embodiment of the present disclosure, the current value of the output current of the first battery pack 102 may be detected through a current value detection unit. After detecting the current value, the current value detection unit sends the current value of the output current of the first battery pack 102 to a first input terminal of the subtractor 1081.

[0111] This embodiment of the present disclosure does not limit the manner in which the subtractor 1081 receives the current value of the output current of the first battery pack 102 and the reference current value.

[0112] In this embodiment of the present disclosure, the subtractor 1082 is configured to calculate the difference between the current value of the first battery pack 102 and a reference current value. The reference current value is typically set to a value of a sinusoidal or square wave current. In one example, the frequency f of the sinusoidal or square wave current may be set in the range of 10 Hz to 2000 Hz, and the amplitude A may be set in the range of 5 to 200.

[0113] The control subunit 1082 is further configured to generate a PWM signal generation command according to the calculation result of the subtractor 1081 and output the PWM signal generation command to the PWM signal generation subunit 1083 when the average temperature of the temperature of the first battery pack 105 and the temperature of the second battery pack 106, the highest temperature among the temperature of the first battery pack 105 and the temperature of the second battery pack 106, the temperature of the first battery pack 102, or the temperature of the second battery pack 103 is less than a preset temperature.

[0114] The PWM signal generating sub-unit 1083 is configured, under the control of the control sub-unit 1082, to output a PWM signal with an adjustable duty cycle.

[0115] The inverter 1084 is configured to invert the level output by the PWM signal generating sub-unit 1083 .

[0116] In this embodiment of the present disclosure, the PWM signal generated by the PWM signal generating sub-unit 1083 may be used to control the first battery pack 102 to charge the second battery pack 103 when the reference current value is greater than 0. Correspondingly, when the reference current value is less than 0, the second battery pack 103 is controlled to charge the first battery pack 102.

[0117] This embodiment of the present disclosure provides a control unit 108 with a simple structure, which can reduce the difficulty of designing the battery circuit provided in the embodiment of the present disclosure.

[0118] In one embodiment of the present disclosure, when the preset temperature is −10° C., the first battery pack 102 is a power-type battery pack, the second battery pack 103 is an energy-type battery pack, the reference current is a sine wave, the frequency f of the sine wave is 200 Hz, and the amplitude A of the sine wave is 30, the simulation results of the operating current of the first battery pack 102 and the operating current of the second battery pack 103 may be as shown in FIG. 3 .

[0119] It should be noted that in this embodiment of the present disclosure, the subtractor 1081 may periodically receive the current value of the output current of the first battery pack 102. This can achieve closed-loop negative feedback regulation, which can change the duty cycle of the PWM signal generated by the PWM signal generating sub-unit 1083, thereby allowing the temperatures of the first battery pack 102 and the second battery pack 103 to quickly rise above the preset temperature through self-heating.

[0120] In one embodiment of the present disclosure, when the first battery pack 102 is a power-type battery pack and the second battery pack 103 is an energy-type battery pack, the battery circuit 100 provided in this embodiment of the present disclosure further includes a filter unit 109, as shown in FIG. 4 .

[0121] A first terminal of the filter unit 109 is connected to the positive electrode of the first battery pack 102. A second terminal of the filter unit 109 is connected to the power supply terminal 101. A third terminal of the filter unit 109 is connected to the negative electrode of the first battery pack 102.

[0122] In this embodiment of the present disclosure, the powered battery pack is typically used only when peak power (e.g., peak discharge power generated during driving, peak charge power generated during braking) occurs while the electric or hybrid vehicle is running, and the output current of the powered battery pack is expected to be zero at other times. In these cases, the provision of the filter unit 109 can suppress the current ripple of the first battery pack 102 and prevent the output current of the powered battery pack (first battery pack 102) from fluctuating around zero. This can avoid high-frequency rapid charging / discharging of the first battery pack 102, thereby reducing the lifespan reduction of the first battery pack 102.

[0123] In one embodiment of the present disclosure, as shown in FIG. 5, the filter unit 109 includes a first inductor 1091 and a first capacitor 1092.

[0124] A first terminal of the first inductor 1091 is connected to the positive electrode of the first battery pack 102. A second terminal of the first inductor 1091 is connected to the power supply terminal.

[0125] A first terminal of the first capacitor 1092 is connected to a first terminal of the first inductor 1091. A second terminal of the first capacitor 1092 is connected to the negative electrode of the first battery pack 102.

[0126] Of course, other configurations of the filter unit 109 may be used and will not be described in detail in this embodiment of the disclosure.

[0127] In this embodiment of the present disclosure, first inductor 1091 is a filter inductor and may be configured with a value in the range of 2 μH to 1500 μH. First capacitor 1092 is a filter capacitor and may be configured with a value in the range of 2 μF to 1500 μF.

[0128] When the first battery pack 102 has a filtering function, the first inductor 1091 and the first capacitor 1092 may be configured with relatively small values. For example, the first inductor 1091 may be configured with a value of 2 μH, and the first capacitor 1092 may be configured with a value of 2 μF.

[0129] Correspondingly, when the first battery pack 102 does not have a filtering function, the first inductor 1091 and the first capacitor 1092 may be configured with relatively large values. For example, the first inductor 1091 may be configured with a value of 1500 μH, and the first capacitor 1092 may be configured with a value of 1500 μF.

[0130] This embodiment of the present disclosure provides a filter unit 109 with a simple structure, which can reduce the hardware cost, design difficulty, and footprint of the battery circuit 100.

[0131] In one embodiment of the present disclosure, as shown in FIG. 4, the battery circuit 100 provided in this embodiment of the present disclosure further includes a first reflux unit 110 and a second reflux unit 111.

[0132] An input terminal of the first return unit 110 is connected to a second terminal of the first switch 105. An output terminal of the first return unit 110 is connected to a first terminal of the first switch 105.

[0133] An input terminal of the second freewheeling unit 111 is connected to a second terminal of the second switch 106. An output terminal of the second freewheeling unit 111 is connected to a first terminal of the second switch 106.

[0134] In this embodiment of the present disclosure, at the initial moment of closing the second switch 106 and opening the first switch 105, the first switch 105 cannot usually be controlled to open immediately due to the reflux time and operating time of the first switch 105. As a result, a short circuit occurs quickly between the first switch 105 and the second switch 106, which causes the first battery pack 102 and the second battery pack 103 to burn out.

[0135] In this embodiment of the present disclosure, the second reflux unit 111 is connected in parallel with the two terminals of the second switch 106, and the second reflux unit 111 performs reflux, thereby delaying the time to close the second switch 106 during the control to open the first switch 105, thereby preventing the first battery pack 102 and the second battery pack 103 from burning out.

[0136] Similarly, the first reflux unit 110 is connected in parallel to the two terminals of the first switch 105, and performs reflux. This delays the time when the first switch 105 is closed during control to open the second switch 106, thereby preventing the first battery pack 102 and the second battery pack 103 from burning out.

[0137] In one embodiment of the present disclosure, the first freewheeling unit 110 is a first diode 1101, and the second freewheeling unit 111 is a second diode 1111, as shown in FIG.

[0138] The anode of the first diode 1101 is connected to the second terminal of the first switch 105. The cathode of the first diode 1101 is connected to the first terminal of the first switch 105.

[0139] The anode of the second diode 1111 is connected to the second terminal of the second switch 106. The cathode of the second diode 1111 is connected to the first terminal of the second switch 106.

[0140] In this embodiment of the present disclosure, the first reflux unit 110 and the second reflux unit 111 are provided with a simple structure, which can reduce the hardware cost, design difficulty, and installation area of ​​the battery circuit 100.

[0141] In one embodiment of the present disclosure, as shown in FIG. 4, the battery circuit 100 provided in this embodiment of the present disclosure further includes a voltage stabilization unit 112.

[0142] The voltage stabilization unit 1121 is connected between the power supply terminal 101 and the ground terminal 107 .

[0143] In this embodiment of the present disclosure, the voltage stabilization unit 112 is configured to remove voltage fluctuations on the bus that may stabilize the voltage supplied to the load, i.e., on the line on which the power supply terminal 101 of the battery circuit 100 is located, and is further configured to reduce the adverse effects of voltage fluctuations jointly generated by the first battery pack 102 and the transformer unit 104 on the second battery pack 103.

[0144] In one embodiment of the present disclosure, as shown in Figure 5, the voltage stabilization unit 112 may illustratively be a second capacitor 1121. Of course, the voltage stabilization unit 112 may be implemented in other ways.

[0145] In one embodiment of the present disclosure, the second capacitor 1121 is a support capacitor, and the second capacitor 1121 may be configured with a value ranging from 2 μF to 1500 μF.

[0146] This embodiment of the present disclosure provides a voltage stabilization unit 112 with a simple structure, which can reduce the hardware cost, design difficulty, and footprint of the battery circuit 100.

[0147] An embodiment of the present disclosure further provides a vehicle, the vehicle including the battery circuit 100 of any of the above-described embodiments.

[0148] In this embodiment of the present disclosure, the vehicle is an electric vehicle or a hybrid vehicle.

[0149] The embodiments of the present disclosure have been described above. The above description is illustrative and not exhaustive, and the present disclosure is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the various embodiments. The choice of terms used herein is intended to provide the best explanation of the principles, practical applications, or technical improvements of the technology in the marketplace of the various embodiments, or to enable those skilled in the art to understand the embodiments disclosed herein. The scope of the present disclosure is defined by the appended claims.

Claims

1. A battery circuit (100) comprising a power supply terminal (101), a first battery pack (102), a second battery pack (103) of a type different from the first battery pack (102), a voltage transformer unit (104), a first switch (105), a second switch (106), a ground terminal (107), and a control unit (108), The positive electrode of the first battery pack (102) is connected to the power supply terminal (101), and the negative electrode of the first battery pack (102) is connected to the positive electrode of the second battery pack (103), The negative electrode of the second battery pack (103) is connected to the ground terminal (107); a first terminal of the first switch (105) is connected to the power supply terminal (101), a second terminal of the first switch (105) is connected to a first terminal of the second switch (106), and a control terminal of the first switch (105) is connected to a first output terminal of the control unit (108); a second terminal of the second switch (106) is connected to the ground terminal (107), and a control terminal of the second switch (106) is connected to a second output terminal of the control unit (108); the transformer unit (104) is connected between the negative electrode of the first battery pack (102) and the second terminal of the first switch (105); the control unit (108) is configured to control the first switch (105) and the second switch (106) to close or open according to at least one of a temperature of the first battery pack (102) and a temperature of the second battery pack (103); The first battery pack (102) is a power battery pack, the second battery pack (103) is an energy battery pack, and the battery circuit (100) further comprises a filter unit (109); A battery circuit (100) in which a first terminal of the filter unit (109) is connected to the positive electrode of the first battery pack (102), a second terminal of the filter unit (109) is connected to the power supply terminal (101), and a third terminal of the filter unit (109) is connected to the negative electrode of the first battery pack (102).

2. The control unit (108) controlling the first switch (105) and the second switch (106) to close or open according to a first preset control rule when any of the average temperature of the first battery pack (102) and the second battery pack (103), the highest temperature of the temperatures of the first battery pack (102) and the second battery pack (103), the temperature of the first battery pack (102), or the temperature of the second battery pack (103) is below a preset temperature, in order to bring the first battery pack (102) and the second battery pack (103) into a state of charging each other; controlling the first switch (105) and the second switch (106) to close or open according to a second preset control rule when any of the average temperature of the temperatures of the first battery pack (102) and the second battery pack (103), the highest temperature among the temperatures of the first battery pack (102) and the second battery pack (103), the temperature of the first battery pack (102), or the temperature of the second battery pack (103) is equal to or higher than a preset temperature, in order to put the first battery pack (102) and the second battery pack (103) into a state other than the state of charging each other; The battery circuit (100) of claim 1 configured to implement:

3. the deviation between the rated voltage of the first battery pack (102) and the rated voltage of the second battery pack (103) is less than a first preset range; and / or 2. The battery circuit (100) of claim 1, wherein a deviation between a ratio of the capacity of the first battery pack (102) to the capacity of the second battery pack (103) and a ratio of a maximum discharge rate of the second battery pack (103) to a maximum discharge rate of the first battery pack (102) is less than a second preset range.

4. the rated voltage of the first battery pack (102) is the same as the rated voltage of the second battery pack (103); and / or 4. The battery circuit (100) of claim 3, wherein the ratio of the capacity of the first battery pack (102) to the capacity of the second battery pack (103) is the same as the ratio of the maximum discharge rate of the second battery pack (103) to the maximum discharge rate of the first battery pack (102).

5. The control unit (108) comprises a subtractor (1081), a control subunit (1082), a pulse width modulation (PWM) signal generating subunit (1083), and an inverter (1084); a first input terminal of the subtractor (1081) configured to receive a current value of the first battery pack (102), a second input terminal of the subtractor (1081) configured to receive a reference current value, and an output terminal of the subtractor (1081) connected to an input terminal of the control sub-unit (1082); A first output terminal of the control sub-unit (1082) is connected to an input terminal of a PWM signal generating sub-unit (1083); a first output terminal of the PWM signal generating sub-unit (1083) connected to the control terminal of the first switch (105), and a second output terminal of the PWM signal generating sub-unit (1083) connected to the input terminal of the inverter; 2. The battery circuit (100) of claim 1, wherein an output terminal of the inverter (1084) is connected to the control terminal of the second switch (106).

6. The filter unit (109) comprises a first inductor (1091) and a first capacitor (1092); a first terminal of the first inductor (1091) connected to the positive electrode of the first battery pack (102), and a second terminal of the first inductor (1091) connected to the power supply terminal (101); 2. The battery circuit (100) of claim 1, wherein a first terminal of the first capacitor (1092) is connected to the first terminal of the first inductor (1091) and a second terminal of the first capacitor (1092) is connected to the negative terminal of the first battery pack (102).

7. Further comprising a first reflux unit (110) and a second reflux unit (111); an input terminal of the first reflux unit (110) is connected to the second terminal of the first switch (105), and an output terminal of the first reflux unit (110) is connected to the first terminal of the first switch (105); 2. The battery circuit (100) of claim 1, wherein an input terminal of the second reflux unit (111) is connected to the second terminal of the second switch (106), and an output terminal of the second reflux unit (111) is connected to the first terminal of the second switch (106).

8. The first reflux unit (110) is a first diode (1101), and the second reflux unit (111) is a second diode (1111); The anode of the first diode (1101) is connected to the second terminal of the first switch (105), and the cathode of the first diode (1101) is connected to the first terminal of the first switch (105); 8. The battery circuit (100) of claim 7, wherein the anode of the second diode (1111) is connected to the second terminal of the second switch (106) and the cathode of the second diode (1111) is connected to the first terminal of the second switch (106).

9. Further comprising a voltage stabilization unit (112), 2. The battery circuit (100) of claim 1, wherein the voltage stabilization unit (112) is connected between the power supply terminal (101) and the ground terminal (107).

10. 10. The battery circuit (100) of claim 9, wherein the voltage stabilization unit (112) is a second capacitor (1121).

11. 2. The battery circuit (100) of claim 1, wherein the transformer unit (104) is a second inductor (1041).

12. A vehicle comprising a battery circuit (100) according to any one of claims 1 to 11.

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