Controller, system and method for managing battery pack

Abstract

The present invention provides a controller, system and method for managing a battery pack. The battery controller includes a first drive port, a second drive port and a third drive port. The first drive port is coupled to a charging switch, and is used to turn on the charging switch to allow a power source to charge the battery pack. The second drive port is coupled to a first discharge switch, and is used to turn on the first discharge switch to allow the battery pack to supply power to a first load. The third drive port is coupled to a second discharge switch, and is used to turn on the second discharge switch to allow the battery pack to supply power to a second load. The present invention utilizes independent discharge switches and corresponding drive ports, so that the battery controller can independently control each discharge circuit.

Description

[0001] This case is a divisional application of the invention patent application with the application date of January 21, 2019, application number 201910054748.2, and invention name "Controller, system and method for managing battery packs". Technical Field

[0002] The present invention relates to a battery management system, and in particular to a controller, system and method for managing a battery pack. Background Art

[0003] Figure 1 A conventional battery management system 100 is shown. The battery management system 100 includes a front-end circuit 112, such as a digital front-end circuit (DFE) or an analog front-end circuit (AFE). The front-end circuit 112 monitors the voltage of each battery cell in a plurality of battery cells 110 included in the battery pack, as well as the current and temperature of the battery pack. The plurality of battery cells 110 are charged by a power source 118 and can supply power to a load 116. Data related to the battery cells and the battery pack are transmitted from the front-end circuit 112 to a conventional microcontroller unit (MCU) 114. Based on these data, the MCU 114 monitors the safety status and health status of the battery pack. The safety status includes overvoltage, undervoltage, overtemperature, short circuit, overcurrent and the like. The health status includes the balance state and charge state of the battery cells. The MCU 114 controls the discharge and charge of the battery pack by controlling the discharge switch 102 and the charge switch 104. The discharge switch 102 and the charge switch 104 are usually implemented using metal oxide semiconductor field effect transistors (MOSFETs).

[0004] Figure 1 The ports of the conventional MCU 114 only include low voltage (usually less than 5V) general purpose input / output ports (GPIO). However, the MOSFETs used as the discharge switch 102 and the charge switch 104 usually require a higher voltage (such as 10V to 20V) to drive. Therefore, in order to drive the discharge switch 102 and the charge switch 104, the system needs to include additional independent drivers 122 and 124, thereby increasing the cost, circuit size, and power consumption. Summary of the invention

[0005] The present invention provides a battery controller. The battery controller includes a first drive port, a second drive port and a third drive port. The first drive port is coupled to a charging switch, and is used to turn on the charging switch to allow a power supply to charge a battery pack. The second drive port is coupled to a first discharge switch, and is used to turn on the first discharge switch to allow the battery pack to supply power to a first load. The third drive port is coupled to a second discharge switch, and is used to turn on the second discharge switch to allow the battery pack to supply power to a second load.

[0006] The present invention also provides a battery management system, which includes a master controller and a slave controller. The master controller monitors and manages a first group of battery cells, wherein the master controller receives a first current from the first group of battery cells. The slave controller monitors and manages a second group of battery cells, wherein the slave controller receives a second current from the second group of battery cells. The slave controller generates a signal indicating the magnitude of the second current and transmits the signal to the master controller. The master controller adjusts the first current and controls the slave controller to adjust the second current.

[0007] The present invention also provides a method for managing a battery pack, the method comprising: using a main controller to manage a first group of battery cells, the main controller receiving a first current from the first group of battery cells; using a slave controller to manage a second group of battery cells, the slave controller receiving a second current from the second group of battery cells; and using the main controller to balance the first current and the second current.

[0008] The present invention uses a main controller to balance the current consumed by the main controller and the current consumed by the slave controller, so that the imbalance between each group of battery cells can be reduced or eliminated. On the other hand, the battery management system of the present invention can include two discharge circuits, and the main controller can independently control each discharge circuit using a dedicated discharge switch and a corresponding drive port. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The following description in combination with some embodiments of the present invention and the accompanying drawings may further provide an understanding of the objectives, specific structural features and advantages of the present invention.

[0010] Figure 1 Shown is a conventional battery management system;

[0011] Figure 2 A battery management system according to an embodiment of the present invention is shown;

[0012] Figure 3 A battery management system according to an embodiment of the present invention is shown;

[0013] Figure 4 A battery management system according to an embodiment of the present invention is shown;

[0014] Figure 5 A battery management system according to an embodiment of the present invention is shown;

[0015] Figure 6 A battery controller according to one embodiment of the present invention is shown;

[0016] Figure 7 The figure shows an analog / digital converter in a battery controller according to one embodiment of the present invention;

[0017] Figure 8 FIG. 1 is a flow chart of a method for managing a battery pack according to an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The following will provide a detailed description of embodiments of the present invention. Although the present invention is described and illustrated by these embodiments, it should be noted that the present invention is not limited to these embodiments. On the contrary, the present invention encompasses all substitutes, variants and equivalents within the spirit of the invention and the scope of the invention as defined by the appended claims.

[0019] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. Those skilled in the art will appreciate that the present invention can be implemented without these specific details. In other examples, well-known methods, processes, components and circuits are not described in detail to highlight the subject matter of the present invention.

[0020] Figure 2 The figure shows a battery management system 200 according to one embodiment of the present invention. The battery management system 200 includes a battery controller 212 for monitoring and managing a plurality of battery cells 210. Specifically, the battery management system 212 monitors the voltage of each battery cell in the plurality of battery cells 210, monitors the total voltage of the plurality of battery cells 210, and balances and protects the battery cells. The battery controller 212 and the battery cells 210 may be integrated into a battery pack 222. The battery controller 212 controls the charging switch 204 and the discharging switch 202 to control the charging and discharging of the plurality of battery cells 210. The charging switch 204 and the discharging switch 202 may be metal oxide semiconductor field effect transistors (MOSFETs) that need to be driven by a higher voltage driving signal. In one embodiment, the ports of the battery controller 212 include VBAT, ISP, ISN, DSG, and CHG.

[0021] The voltage detection port VBAT detects the total voltage of the plurality of battery cells 210. The current detection ports ISP and ISN detect the current through the current detection resistor R S The voltage difference between the two ends is used to detect the charging current and discharging current. SThe first drive port CHG is coupled to the charging switch 204 and the discharging switch 202, and the charging switch 204 can be turned on to allow the power supply 218 to charge the battery pack 222. The second drive port DSG is coupled to the discharging switch 202 and the discharging switch 202 can be turned on to allow the battery pack 222 to power the load 220. In one embodiment, a microcontroller unit (MCU) is integrated in the battery controller 212. The second drive port DSG is implemented using a general purpose input / output port (GPIO) of the MCU and can output a drive signal with a higher voltage (for example, higher than 5V) to control the discharging switch 202. The first drive port CHG and the second drive port DSG are directly connected to the charging switch 204 and the discharging switch 202, respectively. Therefore, the battery management system 200 does not need to include Figure 1 Independent drivers 122 and 124 in.

[0022] Figure 3 FIG. 3 is a diagram showing a battery management system 300 according to an embodiment of the present invention. The battery management system 300 includes a battery controller 312 for monitoring and managing a plurality of battery cells 210. The battery controller 312 and the plurality of battery cells 210 may be integrated within a battery pack 322. For simplicity, Figure 3 The power source for charging the battery pack 322 is not shown. Figure 3 In the example of FIG. 1 , the battery management system 300 includes two discharge loops. The first discharge loop includes a first discharge switch 302, and the second discharge loop includes a second discharge switch 308. The first discharge switch 302 is coupled to a first load 310, and the second discharge switch 308 is coupled to a second load 320. In one embodiment, the ports of the battery controller 312 include VBAT, ISP, ISN, PA1, DSG1, DSG2, and CHG.

[0023] The voltage detection port VBAT detects the total voltage of multiple battery cells 210. The battery controller 312 uses the current detection ports ISP, ISN and PA1 to detect the charging current and the discharging current. Specifically, the first discharge current in the first discharge loop is detected by detecting the voltage difference across the current detection resistor R1 connected in series with the first discharge switch 302. One end of the current detection resistor R1 is coupled to the port ISP, and the other end is coupled to the port ISN. The second discharge current in the second discharge loop is detected by detecting the voltage difference across the current detection resistor R2 connected in series with the second discharge switch 308. One end of the current detection resistor R2 is coupled to the port ISP, and the other end is coupled to the port PA1. Such a connection mode of resistors R1 and R2 is called a parallel mode. The first drive port CHG is coupled to the charging switch 304, and is used to turn on the charging switch 304 to allow the power supply ( Figure 3The first discharge circuit 300 is used to charge the battery pack 322. The second driving port DSG1 is coupled to the first discharge switch 302, and is used to turn on the first discharge switch 302 to allow the battery pack 322 to power the first load 310 through the first discharge circuit. The third driving port DSG2 is coupled to the second discharge switch 308, and is used to turn on the second discharge switch 308 to allow the battery pack 322 to power the second load 320 through the second discharge circuit.

[0024] In one embodiment, an MCU is integrated in the battery controller 312, and the second drive port DSG1 and the third drive port DSG2 are implemented using the GPIO of the MCU, and can output a drive signal with a higher voltage (for example, higher than 5V) to directly control the first discharge switch 302 and the second discharge switch 308. Therefore, the battery management system 300 does not need to use independent drivers to drive these discharge switches. In one embodiment, the current detection port PA1 is also implemented using the GPIO of the MCU.

[0025] Figure 4 FIG. 4 is a diagram showing a battery management system 400 according to an embodiment of the present invention. Figure 3 The battery management system 300 in FIG. 4 is similar to the battery management system 300 in FIG. 4 , except that the connection method of the current detection resistors R1 and R2 in the battery pack 422 is different. Figure 4 In the example, one end of resistor R1 is coupled to port ISP, and the other end is coupled to port ISN. One end of resistor R2 is coupled to port ISN, and the other end is coupled to port PA1. This connection mode of resistors R1 and R2 is called series mode. Figure 4 In the example, the resistor R1 is coupled to the first discharge circuit (the first discharge circuit includes the first discharge switch 304) and is also coupled to the second discharge circuit (the second discharge circuit includes the second discharge switch 308) for detecting a first discharge current in the first discharge circuit and a second discharge current in the second discharge circuit. Both the first discharge current and the second discharge current flow through the resistor R1.

[0026] Figure 5 A battery management system 500 according to one embodiment of the present invention is shown. Figure 3 and Figure 4 The battery management systems 300 and 400 in the Figure 5 The battery management system 500 in the embodiment is implemented, that is, the battery management system 500 can be used to replace the battery management systems 300 and 400. Figure 5In the example, the connection mode of the resistors R1 and R2 adopts a series mode, and in other examples, the connection mode of the resistors R1 and R2 can also adopt a parallel mode. The battery management system 500 includes a main controller 502 and two slave controllers 504 and 506. The main controller 502, the slave controller 504 and the slave controller 506 respectively monitor and manage a group of corresponding battery cells. For example, the main controller 502 monitors and manages the first group of battery cells 530, the slave controller 504 monitors and manages the second group of battery cells 520, and the slave controller 506 monitors and manages the third group of battery cells 510. The battery management system 500 includes two discharge circuits controlled by the main controller 502. The first discharge circuit includes a first discharge switch 302, such as Figure 3 and Figure 4 As shown in the example, the first discharge switch 302 can be connected to the first load ( Figure 5 The second discharge circuit includes a second discharge switch 308, such as Figure 3 and Figure 4 As shown in the example, the second discharge switch 308 can be connected to the second load ( Figure 5 The first current detection resistor R1 is connected in series with the first discharge switch 302 to detect the first discharge current in the first discharge loop. The second current detection resistor R2 is connected in series with the second discharge switch 308 to detect the second discharge current in the second discharge loop.

[0027] In one embodiment, the ports of the main controller 502 include VBAT, ISP, ISN, PB1, PB2, PA1, DSG1, DSG2, CHG and VCC. The voltage detection port VBAT detects the total voltage of the first group of battery cells 530. The main controller 502 uses the current detection ports ISP, ISN and PA1 to detect the charging current and the discharging current. Specifically, the first discharge current in the first discharge loop is detected by detecting the voltage difference across the first current detection resistor R1 connected in series with the first discharge switch 302. One end of the current detection resistor R1 is coupled to the port ISP, and the other end is coupled to the port ISN. The second discharge current in the second discharge loop is detected by detecting the voltage difference across the current detection resistor R2 connected in series with the second discharge switch 308. One end of the current detection resistor R2 is coupled to the port ISN, and the other end is coupled to the port PA1. The first drive port CHG is coupled to the charging switch 304 for turning on the charging switch 304. The second drive port DSG1 is coupled to the first discharge switch 302 for turning on the first discharge switch 302. The third driving port DSG2 is coupled to the second discharging switch 308 and is used to turn on the second discharging switch 308. The main controller 502 receives the first current I from the first group of battery cells 530. BAT1 (the current of a group of battery cells) and the current from the entire battery pack I CC(battery pack current). The total current consumed by the main controller 502 is the first current I BAT1 With the second current I CC In other words, the first group of battery cells 530 monitored and managed by the main controller 502 provides the first current I BAT1 The first battery cell group 530, the second battery cell group 520 and the third battery cell group 510 jointly provide the main controller 502 with a second current I CC The main controller 502 receives a first current I from the port VBAT. BAT1 , receiving the second current I from the port VCC CC .

[0028] The slave controller 504 receives the current I generated by the second group of battery cells 520 from the port VBAT. BAT2 The slave controller 506 receives the current I generated by the third battery cell group 510 from the port VBAT. BAT3 The master controller 502 communicates with the slave controller 504 and the slave controller 506 through a communication port. In one embodiment, the communication port of the master controller 502 includes ports PB1 and PB2 for differential communication. The master controller 502 receives an indication current I BAT2 The signal of the magnitude of the current I BAT3 The magnitude of the signal and the current I BAT1 ,I BAT2 and I BAT3 Specifically, the main controller 502 performs balancing according to the current I BAT2 and I BAT3 Adjustment current I BAT1 , and / or generate a balancing command to adjust the current I BAT2 and I BAT3 The master controller 502 generates a balancing command and transmits the balancing command to the slave controller 504 and the slave controller 506 through the communication port. The slave controller 504 and the slave controller 506 adjust the current I BAT2 and I BAT3 The goal of adjustment is to make the current I BAT1 ,I BAT2 and I BAT3 As a result, each group of battery cells 510, 520, 530 provides equal current to the corresponding controller, thereby reducing or eliminating the imbalance between each group of battery cells 510, 520, 530.

[0029] Figure 6 FIG. 1 is a diagram showing a battery controller according to an embodiment of the present invention, such as Figure 5The main controller 502 includes a current detector 606, a current controlled oscillator 608, a module balancing circuit 660, a multiplexer 610, an analog / digital converter 667, a coulomb counter 668, an overcurrent / short circuit protection unit 612, a voltage shift unit 616, and an MCU 614. The port VBAT of the main controller 502 detects the total voltage of the first group of battery cells 530 and receives the current I generated by the first group of battery cells 530. BAT1 Current I BAT1 Flows into the main controller 502 and flows through the current detector 606. The current detector 606 detects the current I BAT1 The magnitude of the current I BAT1 The current controlled oscillator 608 receives the detection signal IBATSEN and generates an indication current I BAT1 In one embodiment, the first signal CKP1 is a clock signal, and its frequency is related to the current I BAT1 More specifically, the frequency F1 of the first signal CKP1 can be written as:

[0030] F1=K×IBATSEN (1)

[0031] Where K is the gain of the current controlled oscillator 608. The value of K is unknown in the initial case. The main controller 502 can use a preset reference voltage V REF Calculate the value of K. In one embodiment, using the reference voltage V REF and a resistor (not shown in Figure 6 (middle) generates a relatively accurate reference current I REF . Reference current I REF Applied to the current controlled oscillator 608 to generate the clock signal CKP REF . Because the reference current I REF It is known that by measuring the clock signal CKP REF The frequency gain K can be obtained. Once the gain K is known, the current I BAT1 The corresponding relationship between the first signal CKP1 output by the current controlled oscillator 608 can be determined.

[0032] Multiplexer 610 is coupled to ports ISN, ISP, and PA1 and receives current from current sensing resistors R1 and R2 (shown in FIG. Figure 5 ) detection signal. Figure 5 In the example of FIG. 5 , resistors R1 and R2 are configured in series mode, and the multiplexer 610 can selectively input detection signals from ISP and ISN to detect the total discharge current flowing through the first discharge loop and the second discharge loop. Figure 3With a similar structure, the resistors R1 and R2 are configured in parallel mode, and the multiplexer 610 can selectively input the detection signals from ISP and ISN to detect the first discharge current flowing through the first discharge loop, or selectively input the detection signals from ISP and PA1 to detect the second discharge current flowing through the second discharge loop. Figure 4 and Figure 5 Compared with the series mode Figure 3 The parallel mode in the embodiment is more advantageous because the series mode configuration can detect the total discharge current using only one resistor R1, so the battery controller can continuously perform coulomb counting without charge loss.

[0033] The over-current / short-circuit protection unit 612 is coupled to the multiplexer 610 for detecting an over-current or short-circuit condition.

[0034] The MCU 614 integrated in the main controller 502 has a plurality of GPIO ports, and these GPIO ports can be configured to implement different functions. Figure 6 In the example, the GPIO ports include a first group of ports PA1, PA2 ... PAN and a second group of ports PB1, PB2 ... PBN. Each GPIO port can be configured separately for different purposes. Figure 6 In the example of FIG. 5 , PA1 in the first group of ports is used as a current detection port. PB1 and PB2 in the second group of ports are used as communication ports for implementing the master controller 502 and the slave controllers 504 and 506 (shown in FIG. 5 ). Figure 5 ) data transmission between the MCU 614 and other modules in the battery management system (such as the physical layer interface). The configuration of PA1, PB1 and PB2 is only used as an example and not as a limitation. In practical applications, any GPIO port (such as any GPIO port in the first group of ports and the second group of ports) can be used to implement current detection or data transmission. The main controller 502 also includes a transceiver unit 669 (such as a physical layer interface) to implement communication between the MCU 614 and other modules in the battery management system (such as Figure 5 The master controller 502 further includes a GPIO control unit 670. The MCU 614 uses the GPIO control unit 670 to control the first group of ports PA1, PA2 ... PAN. The other two GPIO ports of the MCU 614 are used as drive ports to provide drive signals for the first discharge switch 302 and the second discharge switch 304. The voltage shift unit 616 is coupled to the MCU 614 and is used to shift the voltage of the drive signal to a suitable voltage value before the drive signal is output from the ports DSG1 and DSG2 of the master controller 502. Inside the master controller 502, the first drive port CHG is coupled to the current source 666, and the current source 666 is controlled by the MCU 614.

[0035] The module balancing circuit 660 adjusts the current I flowing into the main controller 502 by adjusting the current consumed by the main controller 502. BAT1 In one embodiment, the module balancing circuit 660 includes a variable resistor. The module balancing circuit 660 increases the resistance of the variable resistor to increase the current I BAT1 The main controller 502 further includes a battery cell balancing circuit (not shown) for monitoring and balancing each battery cell in the first group of battery cells 530 .

[0036] The analog / digital converter 667 and the coulomb counter 668 are coupled to the current detection ports ISN, ISP, and PA1 via the multiplexer 610 to calculate the change in the battery pack charge.

[0037] According to the present invention, a slave controller (such as Figure 5 The slave controller 504 in the embodiment includes fewer components than the master controller 502. For example, the slave controller 504 does not include an MCU. Therefore, the slave controller 504 consumes less power than the master controller 502. The master controller 502 can be divided into two power supply areas. One power supply area includes components similar to the slave controller, and is powered by the current I from the first group of battery cells 530. BAT1 The other power supply area includes components not available from the controller (such as the MCU), which are powered by the current I from the entire battery pack. CC The main controller 502 can use the module balancing circuit 660 to adjust the current I BAT1 The master controller 502 may also generate a balancing command to adjust the current I consumed by the slave controller 504 and the slave controller 506, respectively. BAT2 and current I BAT3 .

[0038] The MCU 614 in the master controller 502 can generate a measurement command and transmit the measurement command to the slave controllers 504 and 506 through the communication port (such as the PB1 and PB2 ports). The measurement command includes time information. After receiving the measurement command, the slave controllers 504 and 506 perform current measurement in the same time period with the master controller 502, that is, measure the current I BAT1 ,I BAT2 and I BAT3 In one embodiment, the slave controllers 504 and 506 each include a module balancing circuit, a current detector, and a current controlled oscillator, which have similar functions to the corresponding components in the master controller 502 .

[0039] Take the slave controller 504 as an example. The current I detected by the current detector in the slave controller 504 BAT2The information is transmitted to the current controlled oscillator in the slave controller 504, thereby generating a current I BAT2 In one embodiment, CKP2 is a clock signal whose frequency is proportional to the current I BAT2 CKP2 is transmitted to the main controller 502 through the communication port. Based on the frequency of CKP2, the main controller 502 compares the current I BAT2 and current I BAT1 In one embodiment, if the current I BAT1 Less than current I BAT2 , the main controller 502 increases the current I by controlling the module balancing circuit 660 BAT1 , for example, increasing the resistance of the variable resistor to consume more power. In another embodiment, if the current I BAT1 Less than current I BAT2 , the master controller 502 generates a balancing command and transmits the balancing command to the slave controller 504. The slave controller 504 uses its internal module balancing circuit to reduce the current I according to the balancing command. BAT2 , for example, by reducing the resistance of the variable resistor to reduce the current I BAT2 As a result, the current I BAT1 and current I BAT2 can be adjusted to be equal to each other. Through a similar process, the current I consumed by the controller 506 BAT3 can be adjusted to match the current I BAT1 ,I BAT2 Finally, each group of battery cells 510 , 520 , 530 provides equal current to its corresponding controller, thereby reducing or eliminating the unbalanced state between each group of battery cells 510 , 520 , 530 .

[0040] Figure 7 FIG. 1 is a diagram showing an analog / digital converter in a battery controller according to an embodiment of the present invention. Figure 6 The analog / digital converter 667 in FIG. The analog / digital converter 667 may be a first-order sigma-delta analog / digital converter, including an adder 702 , an integrator 704 , a comparator 706 , a 1-bit digital / analog converter 710 , and a digital filter 708 .

[0041] If the battery management system adopts Figure 4 or Figure 5The structure is configured such that the resistors R1 and R2 are configured in series mode, and the adder 702 receives the differential signal IN1 (ISP, ISN). The differential signal IN1 (ISP, ISN) indicates the voltage difference across the resistor R1, and also indicates the total discharge current of the first discharge loop and the second discharge loop. The differential signal IN1 (ISP, ISN) is applied to the adder 702 after passing through the first weighting unit 712.

[0042] If the battery management system adopts Figure 3 The structure of the first differential signal IN1 (ISP, ISN) is configured to configure the resistors R1 and R2 in parallel mode, and the adder 702 receives the first differential signal IN1 (ISP, ISN) and the second differential signal IN2 (ISP, PA1). The first differential signal IN1 (ISP, ISN) indicates the voltage difference across the resistor R1, and also indicates the discharge current of the first discharge loop. The second differential signal IN2 (ISP, PA1) indicates the voltage difference across the resistor R2, and also indicates the discharge current of the second discharge loop. The first differential signal IN1 (ISP, ISN) is applied to the adder 702 after passing through the first weighting unit 712. The second differential signal IN2 (ISP, PA1) is applied to the adder 702 after passing through the second weighting unit 714.

[0043] The 1-bit digital / analog converter 710 is coupled to the output of the comparator 706 and provides negative feedback for the adder 702 .

[0044] Integrator 704 integrates the output of adder 702. The output of integrator 704 is applied to the positive terminal of comparator 706. The output of comparator 706 is filtered by digital filter 708 and then transmitted to coulomb counter 668 for calculating the change in battery pack charge.

[0045] Figure 8 Shown is a flow chart 800 of a method for managing a battery pack according to one embodiment of the present invention. Figure 8 Combination Figure 5 and Figure 6 describe.

[0046] In step 802 , the main controller 502 manages the first group of battery cells 530 and receives a first current from the first group of battery cells 530 .

[0047] In step 804 , the slave controller 504 manages the second group of battery cells 520 and receives a second current from the second group of battery cells 520 .

[0048] In step 806, the master controller 502 balances the first current and the second current so that the first current is equal to the second current. In one embodiment, the slave controller 504 generates a signal CKP2 indicating the magnitude of the second current and transmits the signal CKP2 to the master controller 502. The master controller 502 receives the signal CKP2 and adjusts the first current accordingly, and / or transmits a balancing command to the slave controller 504 to adjust the second current.

[0049] The embodiment disclosed in the present invention provides a battery management system, which includes a master controller and one or more slave controllers. The master controller can balance the current consumed by the master controller and each slave controller, so that the imbalance between each group of battery cells can be reduced or eliminated. Furthermore, the battery management system disclosed in the present invention can include two discharge circuits. Using independent discharge switches and corresponding drive ports, the master controller can independently control each discharge circuit.

[0050] The above specific implementation methods and drawings are only common embodiments of the present invention. Obviously, various additions, modifications and substitutions can be made without departing from the spirit and scope of the present invention defined by the claims. It should be understood by those skilled in the art that the present invention can be varied in form, structure, layout, proportion, material, element, assembly and other aspects according to specific environment and working requirements in practical applications without departing from the invention criteria. Therefore, the embodiments disclosed herein are only for illustration and not limitation, and the scope of the present invention is defined by the attached claims and their legal equivalents, and is not limited to the previous description.

Claims

1. A battery controller, characterized in that: The battery controller comprises: A first drive port, coupled to the charging switch, for turning on the charging switch to allow the power source to charge the battery pack; a second driving port, coupled to the first discharge switch, for turning on the first discharge switch to allow the battery pack to supply power to a first load; a micro control unit, the micro control unit comprising a plurality of general purpose input / output ports, the plurality of general purpose input / output ports providing a driving signal to control the first discharge switch; and a voltage shift unit coupled to the micro control unit, Wherein, the voltage shift unit performs voltage shift on the driving signal; Wherein, the battery controller further comprises: a communication port coupled to the slave controller and configured to receive a first signal indicating a magnitude of a first current consumed by the slave controller and transmit a balancing command to the slave controller to adjust the first current, thereby balancing the first current and a second current; a current detector for detecting the second current generated by the first group of battery cells and consumed by the battery controller; The battery controller monitors and manages the first group of battery cells, the slave controller monitors and manages the second group of battery cells, and the first current is generated by the second group of battery cells.

2. The battery controller according to claim 1, characterized in that: The communication ports include two ports for differential communication.

3. The battery controller according to claim 1, characterized in that: The first signal is a clock signal, and a frequency of the first signal is proportional to the first current.

4. The battery controller according to claim 1, characterized in that: The battery controller also includes: A current controlled oscillator is coupled to the current detector and is used to generate a second signal indicating the magnitude of the second current, wherein the second signal is a clock signal and a frequency of the second signal is proportional to the second current.

5. The battery controller according to claim 4, characterized in that: The battery controller also includes: The module balancing circuit is used to adjust the second current.

6. The battery controller according to claim 5, characterized in that: The module balancing circuit includes a variable resistor. If the second current is less than the first current, the battery controller increases the resistance of the variable resistor to increase the second current.

7. The battery controller according to claim 4, characterized in that: If the first current is less than the second current, the battery controller generates the balancing command and transmits the balancing command to the slave controller to increase the first current.

8. A battery management system for managing a battery pack comprising a first group of battery cells and a second group of battery cells, characterized in that: The battery management system comprises: a main controller, configured to monitor and manage the first group of battery cells, wherein the main controller consumes a first current generated by the first group of battery cells; and a slave controller, configured to monitor and manage the second group of battery cells, wherein the slave controller consumes a second current generated by the second group of battery cells, Wherein, the main controller comprises: A communication port coupled to the slave controller is used to receive a signal indicating the magnitude of a second current consumed by the slave controller and transmit a balancing command to the slave controller to adjust the second current, thereby balancing the first current and the second current.

9. The battery management system according to claim 8, characterized in that: The signal is generated by the slave controller.

10. The battery management system according to claim 8, characterized in that: The slave controller comprises: a current detector, configured to detect the second current; and a current controlled oscillator, coupled to the current detector, for generating the signal according to the second current, wherein the frequency of the signal is proportional to the second current; The master controller transmits a balancing command to the slave controller to adjust the second current.

11. The battery management system according to claim 8, characterized in that: The battery management system further comprises: A first discharge loop includes a first discharge switch coupled to a first load; and The second discharge circuit includes a second discharge switch coupled to a second load. The main controller outputs a driving signal to control the first discharge switch and the second discharge switch respectively.

12. The battery management system according to claim 11, characterized in that: The battery management system further comprises: A resistor coupled to the first discharge loop and the second discharge loop is used to detect a first discharge current in the first discharge loop and a second discharge current in the second discharge loop, wherein both the first discharge current and the second discharge current flow through the resistor.

13. The battery management system according to claim 8, characterized in that: The slave controller comprises: The module balancing circuit is used to adjust the second current according to the balancing command from the main controller.

14. The battery management system according to claim 13, characterized in that: The module balancing circuit includes a variable resistor, wherein if the second current is less than the first current, the slave controller increases the resistance of the variable resistor to increase the second current.

15. A battery controller, characterized in that: The battery controller comprises: A first drive port, coupled to the charging switch, for turning on the charging switch to allow the power source to charge the battery pack; a second driving port, coupled to the first discharge switch, for turning on the first discharge switch to allow the battery pack to supply power to a first load; a communication port coupled to the slave controller and configured to receive a first signal indicating a magnitude of a first current consumed by the slave controller and transmit a balancing command to the slave controller to adjust the first current, thereby balancing the first current and a second current; Wherein, the battery controller further includes: a current detector for detecting the second current generated by the first group of battery cells and consumed by the battery controller; The battery controller monitors and manages the first group of battery cells, the slave controller monitors and manages the second group of battery cells, and the first current is generated by the second group of battery cells.

16. The battery controller according to claim 15, characterized in that: The communication ports include two ports for differential communication.

17. The battery controller according to claim 15, characterized in that: The first signal is a clock signal, and a frequency of the first signal is proportional to the first current.

18. The battery controller according to claim 15, characterized in that: The battery controller also includes: A current controlled oscillator is coupled to the current detector and is used to generate a second signal indicating the magnitude of the second current, wherein the second signal is a clock signal and a frequency of the second signal is proportional to the second current.

19. The battery controller according to claim 18, characterized in that: The battery controller also includes: The module balancing circuit is used to adjust the second current.

20. The battery controller according to claim 19, characterized in that: The module balancing circuit includes a variable resistor. If the second current is less than the first current, the battery controller increases the resistance of the variable resistor to increase the second current.

21. The battery controller according to claim 18, characterized in that: If the first current is less than the second current, the battery controller generates the balancing command and transmits the balancing command to the slave controller to increase the first current.

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