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 content of the above application is incorporated herein by reference.

[0002] This disclosure relates to the field of vehicle technology, and more specifically, to a battery circuit and a vehicle.

Background Art

[0003] In the prior art, a dual - battery pack composed of a power - type battery pack and an energy - type battery pack has been provided.

[0004] Temperature is an important parameter of the battery. How to control a dual - battery pack composed of a power - type battery pack and an energy - type battery pack according to the temperature of the battery has become a technical problem to be solved promptly.

Summary of the Invention

Means for Solving the Problems

[0005] This disclosure intends to provide a novel technical solution regarding a battery circuit.

[0006] There is provided a battery circuit according to a first aspect of the present disclosure, including a power supply terminal, a first battery pack, a second battery pack of a type different 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 the power supply terminal. The negative electrode of the first battery pack is connected to the positive electrode of the second battery pack.

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

[0009] 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 the first output terminal of the control unit.

[0010] The second terminal of the second switch is connected to the ground terminal. The control terminal of the second switch is connected to the second output terminal of the control unit.

[0011] The transformer unit is connected between the negative electrode 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 temperature of the first battery pack and the second battery pack and the temperature of the second battery pack.

[0013] According to an embodiment of the present disclosure, the control unit In order to put the first battery pack and the second battery pack into a charging state with each other, when any one of the average temperature of the temperatures 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 less than the preset temperature, controlling the first switch and the second switch to close or open according to the first preset control rule; In order to put the first battery pack and the second battery pack into a state other than the charging state with each other, when any one of the average temperature of the temperatures 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 the preset temperature, controlling the first switch and the second switch to close or open according to the second preset control rule.

[0014] According to one 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, 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 generation subunit, and an inverter.

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

[0019] The first output terminal of the control subunit is connected to the input terminal of the PWM signal generation subunit.

[0020] The first output terminal of the PWM signal generation subunit is connected to the control terminal of the first switch. The second output terminal of the PWM signal generation 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 an 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] The first terminal of the filter unit is connected to the positive electrode of the first battery pack. The second terminal of the filter unit is connected to the power supply terminal. The third terminal of the filter unit is connected to the negative electrode of the first battery pack.

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

[0025] The first terminal of the first inductor is connected to the positive electrode of the first battery pack. The second terminal of the first inductor is connected to the power supply terminal.

[0026] The first terminal of the first capacitor is connected to the first terminal of the first inductor. The second terminal of the first capacitor is connected to the negative electrode of the first battery pack.

[0027] According to an 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 reflux unit is connected to the second terminal of the first switch. The output terminal of the first reflux unit is connected to the first terminal of the first switch.

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

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

[0031] The anode of the first diode is connected to the second terminal of the first switch. 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. 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 stabilization 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, a vehicle is provided. The vehicle includes a battery circuit in any implementation form of the aforementioned first aspect.

[0038] The self-heating of the dual battery pack composed of the first battery pack and the second battery pack by the battery circuit provided in one embodiment of the present disclosure can be controlled according to the temperature of the battery.

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

[0040] The drawings incorporated herein and constituting a part thereof illustrate embodiments of the present disclosure and are used to explain the principles of the present disclosure together with the description.

Brief Description of the Drawings

[0041]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Description of Reference Numerals

[0042] 100 Battery circuit 101 Power supply 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 sub-unit 1083 Pulse width modulation (PWM) signal generation sub-unit 1084 Inverter 1085 Switch-on signal generation sub-unit 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 stabilization unit 1121 Second capacitor

Embodiments for Carrying Out 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 the components and steps described in the embodiments, as well as the mathematical formulas and numerical values, do not limit the scope of the present disclosure unless otherwise specified.

[0044] The following description of at least one exemplary embodiment is merely illustrative and does not constitute any limitation to the present disclosure and its use or application.

[0045] Technologies, methods, and devices known to those skilled in the art may not be described in detail, but when appropriate, the technologies, methods, and devices should be regarded as part of this specification.

[0046] In the examples shown and described in this specification, any specific value should be construed as merely illustrative and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0047] Note that in the following drawings, like reference numerals and letters indicate like elements. Therefore, once an element is defined in the drawings, it need not be further described in subsequent drawings.

[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 type different from the first battery pack 102, a voltage transformation 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] The first terminal of the first switch 105 is connected to the power supply terminal 101. The second terminal of the first switch 105 is connected to the first terminal of the second switch 106. The control terminal of the first switch 105 is connected to the first output terminal of the control unit 108.

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

[0053] 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.

[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] In this embodiment of the present disclosure, a battery circuit is provided that includes a power supply terminal, a first battery pack, a second battery pack of a type different from the first battery pack, a transformer unit, a first switch, a second switch, a ground terminal, and a control unit. The positive electrode of the first battery pack is connected to the power supply terminal. 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 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 the 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 the second output terminal of the control unit. The transformer unit is connected between the negative electrode 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 temperature of the first battery pack and the temperature of the second battery pack. The self-heating of the dual battery pack composed of the first battery pack and the second battery pack can be controlled according to the temperature of the battery by this battery circuit.

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

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

[0058] In one embodiment of the present disclosure, as shown in FIG. 4, the transformer unit 104 may be the second inductor 1041. Of course, the transformer unit 104 may be implemented in another way.

[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 switches of the same type. Specifically, when the control terminals of the first switch and the second switch receive a high level, both the first switch 105 and the second switch 106 close or open. When the control terminals of the first switch and the second switch receive a low level, both the first switch 105 and the second switch 106 open or close.

[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 power-type battery pack, and the second battery pack 103 is an energy-type battery pack. Alternatively, the first battery pack 102 is an energy-type battery pack, and the second battery pack 103 is a power-type battery pack.

[0064] In this embodiment of the present disclosure, the power-type battery pack is a battery pack with a high power density. The power density is the maximum energy transfer power during charging / discharging of the battery per unit weight or unit volume. Also, in this embodiment of the present disclosure, the voltage value of the power-type 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. The energy density is the energy stored in the battery per unit weight or unit volume. Also, 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] In this embodiment of the present disclosure, the specific types of the first battery pack 102 and the second battery pack 103 are not limited, which can improve the compatibility of the battery circuit 100 provided in the embodiments of the present disclosure.

[0067] In this embodiment of the present disclosure, 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, which may be specifically implemented in the following two ways.

[0068] The first aspect: The first switch 105 and the second switch 106 are controlled to close or open according to the first preset control rule when any one 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 less than the preset temperature, in order to put the first battery pack 102 and the second battery pack 103 into a charging state with each other.

[0069] In this embodiment of the present disclosure, the temperature of the first battery pack 102 is usually the same as 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 among the temperatures of the first battery pack and the second battery pack may represent the temperature of the dual battery pack composed of the first battery pack 102 and the second battery pack 103.

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

[0071] It should be noted that in this embodiment of the present disclosure, the method for the control unit 108 to obtain 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 pack can operate stably. When the temperature of either the second battery pack 102 or the second battery pack 103, the average temperature of the temperatures of the second battery pack and the second battery pack, or the highest temperature among the temperatures of the second battery pack and the second battery pack is less than the preset temperature, it indicates that the first battery pack 102 and 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 the first time period, and to control the second battery pack 103 to discharge in order to charge the first battery pack 102 within the 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, and this may be set according to experience.

[0075] Based on the above, the first preset control rule performs an on / off operation, which includes controlling to close the first switch 105 and open the second switch 106 within the first sub-time period, controlling to open the first switch 105 and close the second switch 106 within the second sub-time period, controlling to open the first switch 105 and close the second switch 106 within the third sub-time period, and controlling to close the first switch 105 and open the second switch 106 within the 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 is a time period after the first sub-time period. The periods corresponding to the first sub-time period and the second sub-time period may be set according to experience. Further, 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 the third sub-time period and is a time period after the third sub-time period. The periods corresponding to the third sub-time period and the fourth sub-time period may be set according to experience. Further, the third sub-time period and the fourth sub-time period form the second time period.

[0078] In this embodiment of the present disclosure, within 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. Within 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 discharges the stored power to the second battery pack 103. That is, the transformer unit 104 implements a boosting function. Thereby, the first battery pack 102 can charge the second battery pack 103.

[0079] Within 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. Within 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 discharges the stored power to the first battery pack 102. That is, the transformer unit 104 implements a boosting function. Thereby, the second battery pack 103 can charge the first battery pack 102.

[0080] In this embodiment, due to the internal resistances of the first battery pack 102 and the second battery pack 103, the temperatures of the first battery pack 102 and the second battery pack 103 can be raised above a preset temperature by self-heating during charging with 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 any one 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 charging state with each other.

[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 open.

[0083] In this embodiment of the present disclosure, when any one 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, 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 the second preset control rule so that the first battery pack 102 and the second battery pack 103 are in a state other than the charging state with each other, that is, a state where self-heating does not occur. For example, in order 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] In this embodiment of the present disclosure, a battery circuit is provided that includes a power supply terminal, a first battery pack, a second battery pack of a type different from the first battery pack, a voltage transformation unit, a first switch, a second switch, a ground terminal, and a control unit. The positive electrode of the first battery pack is connected to the power supply terminal. 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 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 the 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 the second output terminal of the control unit. The voltage transformation unit is connected between the negative electrode 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 temperature of the first battery pack and the temperature of the second battery pack. The self-heating of the dual battery pack composed of the first battery pack and the second battery pack can be controlled according to the temperature of the battery by this battery circuit.

[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 the first preset range.

[0086] In this embodiment of the present disclosure, the first preset range is the allowable range of the 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 the 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] Generally, it should be noted that 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, that is, 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. Thereby, the most efficient energy transfer can be achieved 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, U1 = U2 = 275V may be set.

[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 the second preset range.

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

[0095] In this embodiment of the present disclosure, the second preset range is the allowable range of 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. 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 be, by way of example, ±0.5.

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

[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 the second preset range, the maximum discharge currents of the two battery packs can be made substantially the same. Based on the above, for example, for stable discharge, the two battery packs can be connected in series.

[0099] It should be noted that generally, 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, that is, 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. Thereby, the maximum discharge currents of the two battery packs can be made exactly the same.

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

[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 pre-set control rule 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 on-period and off-period of the first switch and the second switch 106 are controlled according to the duty cycle of the PWM signal.

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

[0104] The first input terminal of the subtractor 1081 is configured to receive the current value of the first battery pack 102. The second input terminal of the subtractor 1081 is configured to receive a reference current value. The output terminal of the subtractor 1081 is connected to the input terminal of the control sub-unit 1082.

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

[0106] The first output terminal of the PWM signal generation subunit 1083 is connected to the control terminal of the first switch 105. The second output terminal of the PWM signal generation subunit 1083 is connected to the input terminal of the 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 a 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 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.

[0109] In one embodiment of the present disclosure, the control subunit 1082 may be, for example, 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 the 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 the first input terminal of the subtracter 1081.

[0111] In this embodiment of the present disclosure, there is no limitation on the method by which the subtracter 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 subtracter 1082 is configured to calculate the difference between the current value of the first battery pack 102 and the reference current value. The reference current value is usually set to the value of a sine wave current or a square wave current. In one example, the frequency f of the sine wave current or the 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] 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 the preset temperature, 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.

[0114] The PWM signal generation subunit 1083 is configured to output a PWM signal having an adjustable duty cycle under the control of the control subunit 1082.

[0115] The inverter 1084 is configured to invert the level output by the PWM signal generation subunit 1083.

[0116] In this embodiment of the present disclosure, when the reference current value is greater than 0, the first battery pack 102 may be controlled to charge the second battery pack 103 using the PWM signal generated by the PWM signal generation subunit 1083. 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] In this embodiment of the present disclosure, a control unit 108 with a simple structure is provided. Thereby, the design difficulty of the battery circuit provided in the embodiment of the present disclosure can be reduced.

[0118] In an 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 can be those 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. Thereby, closed-loop negative feedback regulation can be achieved, thereby changing the duty cycle of the PWM signal generated by the PWM signal generation subunit 1083, and thereby quickly heating the temperatures of the first battery pack 102 and the second battery pack 103 above the preset temperature by 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, as shown in FIG. 4, the battery circuit 100 provided in this embodiment of the present disclosure further includes a filter unit 109.

[0121] The first terminal of the filter unit 109 is connected to the positive electrode of the first battery pack 102. The second terminal of the filter unit 109 is connected to the power supply terminal 101. The 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, since the power-type battery pack is normally used only when peak power (for example, peak discharge power generated during driving and peak charging power generated during braking) occurs during the running of an electric vehicle or a hybrid vehicle, in other cases, it is expected that the output current of the power-type battery pack will be 0. In these cases, by providing the filter unit 109, the current ripple of the first battery pack 102 can be suppressed, and fluctuations near 0 of the output current of the power-type battery pack (the first battery pack 102) can be prevented. Thereby, rapid high-frequency charging / discharging of the first battery pack 102 can be avoided, and thereby the reduction of the service life of the first battery pack 102 can be reduced.

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

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

[0126] Of course, a filter unit 109 with another structure may be used, which will not be described in detail in this embodiment of the present disclosure.

[0127] In this embodiment of the present disclosure, the first inductor 1091 is a filter inductor, and the first inductor 1091 may be configured with a value in the range of 2 μH to 1500 μH. The first capacitor 1092 is a filter capacitor, and the first capacitor 1092 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] In this embodiment of the present disclosure, a filter unit 109 with a simple structure is provided, whereby the hardware cost, the difficulty of design, and the installation area of the battery circuit 100 can be reduced.

[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] The input terminal of the first reflux unit 110 is connected to the second terminal of the first switch 105. The output terminal of the first reflux unit 110 is connected to the first terminal of the first switch 105.

[0133] The input terminal of the second reflux unit 111 is connected to the second terminal of the second switch 106. The output terminal of the second reflux unit 111 is connected to the first terminal of the second switch 106.

[0134] In this embodiment of the present disclosure, at the first moment when the second switch 106 is closed and the first switch 105 is opened, as a result of the reflux time and operation time of the first switch 105, it is usually not possible to control the first switch 105 to open immediately. As a result, a short circuit rapidly occurs between the first switch 105 and the second switch 106, thereby causing 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, the time for closing the second switch 106 during the control of opening the first switch 105 can be delayed, 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 with the two terminals of the first switch 105, and the first reflux unit 110 performs reflux. Thereby, the time for closing the first switch 105 during the control of opening the second switch 106 can be delayed, thereby preventing the first battery pack 102 and the second battery pack 103 from burning out.

[0137] In one embodiment of the present disclosure, as shown in FIG. 5, the first reflux unit 110 is the first diode 1101, and the second reflux unit 111 is the second diode 1111.

[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 with a simple structure are provided, whereby the hardware cost, the design difficulty, and the installation area of the battery circuit 100 can be reduced.

[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 can stabilize the voltage supplied to the load, that is, on the line where 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 FIG. 5, the voltage stabilization unit 112 may, by way of example, be the second capacitor 1121. Of course, the voltage stabilization unit 112 may be implemented in another way.

[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 in the range of 2 μF to 1500 μF.

[0146] In this embodiment of the present disclosure, a voltage stabilization unit 112 with a simple structure is provided, whereby the hardware cost, the difficulty of design, and the installation area of the battery circuit 100 can be reduced.

[0147] One embodiment of the present disclosure further provides a vehicle. The vehicle includes the battery circuit 100 in any of the foregoing 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 exemplary and non-exhaustive, and the present disclosure is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the various embodiments. The selection of terms used herein is intended to provide the best explanation of the principles, actual applications, or technical improvements in the market 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 transformation unit (104), a first switch (105), a second switch (106), a ground terminal (107), and a control unit (108), wherein 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), the first terminal of the first switch (105) is connected to the power supply terminal (101), the second terminal of the first switch (105) is connected to the first terminal of the second switch (106), and the control terminal of the first switch (105) is connected to the first output terminal of the control unit (108), the second terminal of the second switch (106) is connected to the ground terminal (107), and the control terminal of the second switch (106) is connected to the second output terminal of the control unit (108), the voltage transformation 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 the temperature of the first battery pack (102) and the temperature of the second battery pack (103).

2. The control unit (108) is configured to control the first switch (105) and the second switch (106) to close or open according to a first preset control rule when any one 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 less than a preset temperature, in order to put the first battery pack (102) and the second battery pack (103) into a charging state with respect to each other, To set the first battery pack (102) and the second battery pack (103) to a state other than the charging state, when any one 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, control is performed to close or open the first switch (105) and the second switch (106) according to a second preset control rule. The battery circuit (100) according to claim 1, which is configured to perform the above.

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 The battery circuit (100) according to claim 1 or 2, wherein 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 (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 The battery circuit (100) according to 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 first battery pack (102) is a power-type battery pack, the second battery pack (103) is an energy-type battery pack, or The battery circuit (100) according to any one of claims 1 to 4, wherein the first battery pack (102) is an energy-type battery pack and the second battery pack (103) is a power-type battery pack.

6. The control unit (108) includes a subtractor (1081), a control subunit (1082), a pulse width modulation (PWM) signal generation subunit (1083), and an inverter (1084). The first input terminal of the subtractor (1081) is configured to receive the current value of the first battery pack (102), the second input terminal of the subtractor (1081) is configured to receive a reference current value, and the output terminal of the subtractor (1081) is connected to the input terminal of the control subunit (1082). The first output terminal of the control subunit (1082) is connected to the input terminal of the PWM signal generation subunit (1083). The first output terminal of the PWM signal generation subunit (1083) is connected to the control terminal of the first switch (105), and the second output terminal of the PWM signal generation subunit (1083) is connected to the input terminal of the inverter. The output terminal of the inverter (1084) is connected to the control terminal of the second switch (106). The battery circuit (100) according to any one of claims 1 to 5.

7. The first battery pack (102) is a power-type battery pack, the second battery pack (103) is an energy-type battery pack, and the battery circuit (100) further includes a filter unit (109). The first terminal of the filter unit (109) is connected to the positive electrode of the first battery pack (102), the second terminal of the filter unit (109) is connected to the power supply terminal (101), and the third terminal of the filter unit (109) is connected to the negative electrode of the first battery pack (102). The battery circuit (100) according to claim 5.

8. The filter unit (109) includes a first inductor (1091) and a first capacitor (1092). The first terminal of the first inductor (1091) is connected to the positive electrode of the first battery pack (102), and the second terminal of the first inductor (1091) is connected to the power supply terminal (101). The first terminal of the first capacitor (1092) is connected to the first terminal of the first inductor (1091), and the second terminal of the first capacitor (1092) is connected to the negative electrode of the first battery pack (102). The battery circuit (100) according to claim 7.

9. It further includes a first reflux unit (110) and a second reflux unit (111). The input terminal of the first reflux unit (110) is connected to the second terminal of the first switch (105), and the output terminal of the first reflux unit (110) is connected to the first terminal of the first switch (105). The input terminal of the second reflux unit (111) is connected to the second terminal of the second switch (106), and the output terminal of the second reflux unit (111) is connected to the first terminal of the second switch (106). The battery circuit (100) according to any one of claims 1 to 8.

10. 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). 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). The battery circuit (100) according to claim 9.

11. Further comprising a voltage stabilization unit (112). The voltage stabilization unit (112) is connected between the power supply terminal (101) and the ground terminal (107). The battery circuit (100) according to any one of claims 1 to 10.

12. The voltage stabilization unit (112) is a second capacitor (1121). The battery circuit (100) according to claim 11.

13. The transformer unit (104) is a second inductor (1041). The battery circuit (100) according to any one of claims 1 to 12.

14. A vehicle comprising the battery circuit (100) according to any one of claims 1 to 13.

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