CN218102611U

CN218102611U - Battery pack management circuit and battery pack

Info

Publication number: CN218102611U
Application number: CN202121603040.7U
Authority: CN
Inventors: 秦威
Original assignee: Shenzhen Autel Intelligent Aviation Technology Co Ltd
Current assignee: Shenzhen Autel Intelligent Aviation Technology Co Ltd
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2022-12-20
Anticipated expiration: 2031-07-14

Abstract

The embodiment of the utility model provides a relate to electron electric power technical field, in particular to group battery management circuit and group battery. The utility model provides a group battery management circuit and group battery, including main switch circuit, first sampling circuit, second sampling circuit, discharge switch, discharge unit and the control unit. When the control unit outputs a first control signal to the main switch circuit and the first sampling circuit, the main switch circuit conducts the connection between the battery pack and the output port, and the first sampling circuit collects and outputs the voltage of the output port to the second end of the control unit; when the control unit does not receive the voltage of the output port, the control unit controls the second sampling circuit to work, the second sampling circuit collects the voltage of the battery pack and outputs the voltage of the battery pack to the fourth end of the control unit, and the control unit outputs a discharging signal to the discharging switch according to the voltage of the battery pack so as to discharge the battery pack. In the circuit, the battery capacity and the discharge state are determined without communicating with a fuel gauge, and the circuit is simple in design and low in cost.

Description

Battery pack management circuit and battery pack

Technical Field

The embodiment of the utility model provides a relate to electron electric power technical field, in particular to group battery management circuit and group battery.

Background

At present, with the wider application of the high-rate lithium battery, the storage problem of the high-rate lithium battery gradually becomes a focus of people's attention. Especially, when the high-rate lithium battery is stored for a long time at high electric quantity, if scientific storage processing is not carried out, the battery core bulges, so that the aging of the battery core is accelerated. Especially when a plurality of electric cores are used in series, the aged electric cores can further cause the unbalance of the electric quantity of the battery.

At present, in a conventional scheme for high-power storage of a lithium battery, a discharge state and a power state of the battery are generally determined in a mode of communication with a power meter, and then the discharge storage is performed by using a set program according to the power state, so that the mode is not only complex in design but also high in cost.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides an aim at provides a group battery management circuit and group battery need not to confirm battery power with the coulometer communication, and the design is simple and with low costs.

In a first aspect, an embodiment of the present invention provides a method for processing a semiconductor device, comprising: there is provided a battery management circuit comprising: the device comprises a main switch circuit, a first sampling circuit, a second sampling circuit, a discharge switch, a discharge unit and a control unit;

the first end of the main switch circuit is connected with the first end of the battery pack, the second end of the main switch circuit is connected with the first end of the output port, the third end of the main switch circuit is connected with the first end of the control unit, the control unit outputs a first control signal to the main switch circuit, and the main switch circuit conducts connection between the first end of the battery pack and the first end of the output port according to the first control signal;

the first end of the first sampling circuit is connected with the first end of the output port, the second end of the first sampling circuit is connected with the second end of the control unit, the third end of the first sampling circuit is connected with the first end of the control unit, the control unit outputs the first control signal to the first sampling circuit, and the first sampling circuit collects the voltage of the output port according to the first control signal and outputs the voltage of the output port to the second end of the control unit;

the first end of the second sampling circuit is connected with the first end of the battery pack, the second end of the second sampling circuit is connected with the third end of the control unit, the third end of the second sampling circuit is connected with the fourth end of the control unit, the control unit controls the second sampling circuit not to work when receiving the voltage of the output port, and controls the second sampling circuit to work when not receiving the voltage of the output port, so that the second sampling circuit collects the voltage of the battery pack and outputs the voltage of the battery pack to the fourth end of the control unit;

the first end of the discharge unit is connected with the first end of the battery pack, the second end of the discharge unit is connected with the first end of the discharge switch, the second end of the discharge switch is connected with the second end of the output port, the third end of the discharge switch is connected with the fifth end of the control unit, the control unit outputs a discharge signal to the discharge switch according to the voltage of the battery pack, and the discharge switch is switched on according to the discharge signal, so that the battery pack discharges.

In some embodiments, the first sampling circuit comprises a first switching circuit and a first voltage divider circuit;

the first end of the first switch circuit is connected to the first end of the output port, the second end of the first switch circuit is connected to the first end of the first voltage divider circuit, the third end of the first switch circuit is connected to the first end of the control unit, the second end of the first voltage divider circuit is connected to the second end of the control unit, the control unit is configured to output the first control signal to the first switch circuit, and the first switch circuit is configured to turn on the connection between the first end of the output port and the first end of the first voltage divider circuit according to the first control signal, so that the first voltage divider circuit collects the voltage of the output port and outputs the voltage of the output port to the control unit.

In some embodiments, the first switching circuit comprises a first switching tube;

the first end of the first switch tube is connected with the first end of the output port, the second end of the first switch tube is connected with the first end of the first voltage division circuit, and the third end of the first switch tube is connected with the first end of the control unit.

In some embodiments, the first switch tube is a first NMOS tube;

the drain electrode of the first NMOS tube is connected with the first end of the output port, the source electrode of the first NMOS tube is connected with the first end of the first voltage division circuit, and the grid electrode of the first NMOS tube is connected with the first end of the control unit.

In some embodiments, the first voltage divider circuit comprises a first voltage divider resistor and a second voltage divider resistor;

a first end of the first voltage-dividing resistor is connected to a second end of the first switch circuit, a second end of the first voltage-dividing resistor is connected to a second end of the control unit and a first end of the second voltage-dividing resistor, respectively, and a second end of the second voltage-dividing resistor is grounded.

In some embodiments, the second sampling circuit comprises a second switching circuit and a second voltage dividing circuit;

the first end of the second switch circuit is connected to the first end of the battery pack, the second end of the second switch circuit is connected to the first end of the second voltage division circuit, the third end of the second switch circuit is connected to the third end of the control unit, the second end of the second voltage division circuit is connected to the fourth end of the control unit, and the control unit controls on and off between the first end of the second switch circuit and the second end of the second switch circuit.

In some embodiments, the second switching circuit comprises a second switching tube and a third switching tube;

the first end of the second switching tube is connected with the first end of the battery pack, the second end of the second switching tube is connected with the first end of the second voltage division circuit, the third end of the second switching tube is connected with the first end of the third switching tube, and the second end of the third switching tube is connected with the third end of the control unit.

In some embodiments, the second switching tube is a PMOS tube, and the third switching tube is a second NMOS tube;

the source electrode of the PMOS tube is connected with the first end of the battery pack, the drain electrode of the PMOS tube is connected with the first end of the second voltage division circuit, the grid electrode of the PMOS tube is connected with the drain electrode of the second NMOS tube, the grid electrode of the second NMOS tube is connected with the third end of the control unit, and the source electrode of the second NMOS tube is grounded.

In some embodiments, the second voltage dividing circuit comprises a third voltage dividing resistor and a fourth voltage dividing resistor;

a first end of the third voltage-dividing resistor is connected to a second end of the second switch circuit, a second end of the third voltage-dividing resistor is connected to a fourth end of the control unit and a first end of the fourth voltage-dividing resistor, respectively, and a second end of the fourth voltage-dividing resistor is grounded.

In some embodiments, the battery management circuit further includes a first capacitor and a second capacitor, a first terminal of the first capacitor is connected to the first terminal of the second voltage-dividing resistor, a second terminal of the first capacitor is connected to ground, a first terminal of the second capacitor is connected to the first terminal of the fourth voltage-dividing resistor, and a second terminal of the second capacitor is connected to ground.

In some embodiments, the discharge switch is a third NMOS transistor;

the drain electrode of the third NMOS tube is connected with the second end of the discharge unit, the source electrode of the third NMOS tube is connected with the second end of the output port, and the grid electrode of the third NMOS tube is connected with the fifth end of the control unit.

In some embodiments, the discharge unit is a current limiting resistor;

the current limiting resistor is connected between the first end of the battery pack and the drain electrode of the third NMOS tube in series.

In some embodiments, the battery management circuit further comprises a first bias resistor, a second bias resistor, and a third bias resistor;

the first end of the first biasing resistor is connected with the grid electrode of the second NMOS tube, the second end of the first biasing resistor is grounded, the second biasing resistor is connected between the source electrode of the PMOS tube and the drain electrode of the PMOS tube in series, and the third biasing resistor is connected between the source electrode of the third NMOS tube and the drain electrode of the third NMOS tube in series.

In some embodiments, the main switching circuit comprises a fourth NMOS transistor and a fifth NMOS transistor;

the source electrode of the fourth NMOS tube is connected with the first end of the battery pack, the drain electrode of the fourth NMOS tube is connected with the drain electrode of the fifth NMOS tube, the source electrode of the fifth NMOS tube is connected with the second end of the output port, and the grid electrode of the fourth NMOS tube and the grid electrode of the fifth NMOS tube are both connected with the control unit.

In a second aspect, embodiments of the present invention provide a battery pack, including a battery pack management circuit as described in any one of the first aspects.

Compared with the prior art, the beneficial effects of the utility model are that: be different from prior art's condition, the embodiment of the utility model provides a group battery management circuit and group battery, including main switch circuit, first sampling circuit, second sampling circuit, discharge switch, discharge unit and the control unit. When the control unit outputs a first control signal to the main switch circuit and the first sampling circuit, the main switch circuit conducts the connection between the battery pack and the output port, and the first sampling circuit collects and outputs the voltage of the output port to the second end of the control unit; the control unit controls the second sampling circuit to work when not receiving the voltage of the output port, the second sampling circuit collects the voltage of the battery pack and outputs the voltage of the battery pack to the fourth end of the control unit, and the control unit outputs a discharging signal to the discharging switch according to the voltage of the battery pack so as to discharge the battery pack. In the circuit, the battery capacity and the discharge state are determined without communicating with the fuel gauge, and the circuit is simple in design and low in cost.

Drawings

The embodiments are illustrated by the figures of the accompanying drawings which correspond and are not meant to limit the embodiments, in which elements/modules and steps having the same reference number designation may be referred to by similar elements/modules and steps, unless otherwise indicated, and in which the drawings are not to scale.

Fig. 1 is a schematic diagram illustrating a structure of a battery management circuit according to an embodiment of the present invention;

fig. 2 is a schematic diagram of another battery management circuit according to an embodiment of the present invention;

fig. 3 is a schematic circuit diagram of a battery management circuit according to an embodiment of the present invention;

fig. 4 is a schematic circuit diagram of another battery management circuit according to an embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific embodiments. The following examples will aid those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that numerous variations and modifications could be made by those skilled in the art without departing from the spirit of the invention. All of which belong to the protection scope of the present invention.

To facilitate an understanding of the present application, the present application is described in more detail below with reference to the figures and the detailed description. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that, if not conflicted, the various features of the embodiments of the invention can be combined with each other and are within the scope of protection of the present application. In addition, although the functional blocks are divided in the device diagram, in some cases, they may be divided differently from the blocks in the device. Further, the terms "first," "second," and the like, as used herein do not limit the data and the order of execution, but merely distinguish between the same or similar items that have substantially the same function and effect.

In a first aspect, an embodiment of the present invention provides a battery management circuit, please refer to fig. 1, where the battery management circuit includes: the circuit comprises a main switch circuit 10, a first sampling circuit 20, a second sampling circuit 30, a discharge switch 40, a control unit 50 and a discharge unit 60. The first end of the main switch circuit 10 is connected with the first end B + of the battery PACK 200, the second end of the main switch circuit 10 is connected with the first end PACK + of the output port 300, the third end of the main switch circuit 10 is connected with the first end of the control unit 50, the control unit 50 is used for outputting a first control signal to the main switch circuit 10, and the main switch circuit 10 is used for conducting connection between the first end B + of the battery PACK 200 and the first end PACK + of the output port 300 according to the first control signal. The first end of the first sampling circuit 20 is connected to the first end PACK + of the output port 300, the second end of the first sampling circuit 20 is connected to the second end of the control unit 50, the third end of the first sampling circuit 20 is connected to the first end of the control unit 50, the control unit 50 is further configured to output a first control signal to the first sampling circuit 20, and the first sampling circuit 20 is configured to collect the voltage of the output port 300 according to the first control signal and output the voltage of the output port 300 to the second end of the control unit 50. The first end of the second sampling circuit 30 is connected to the first end B + of the battery pack 200, the second end of the second sampling circuit 30 is connected to the third end of the control unit 50, the third end of the second sampling circuit 30 is connected to the fourth end of the control unit 50, and the control unit 50 is further configured to control the second sampling circuit 30 not to operate when receiving the voltage of the output port 300, and to control the second sampling circuit 30 to operate when not receiving the voltage of the output port 300, so that the second sampling circuit 30 collects the voltage of the battery pack 200 and outputs the voltage of the battery pack 200 to the fourth end of the control unit 50. The first end of the discharging unit 60 is connected with the first end B + of the battery PACK 200, the second end of the discharging unit 60 is connected with the first end of the discharging switch 40, the second end of the discharging switch 40 is connected with the second end PACK of the output port 300, the third end of the discharging switch 40 is connected with the fifth end of the control unit 50, the control unit 50 is further configured to output a discharging signal to the discharging switch 40 according to the voltage of the battery PACK 200, and the discharging switch 40 is configured to conduct the connection between the second end of the discharging unit 60 and the second end PACK of the output port 300 according to the discharging signal, so as to discharge the battery PACK 200.

Specifically, the battery pack 200 may be a parallel battery pack, a series battery pack, or a series-parallel battery pack, and includes at least one high-rate battery cell, where the high-rate battery cell is a battery cell with a discharge rate exceeding 1C. Typically, the first terminal B + of the battery PACK 200 is the positive pole of the battery PACK, the second terminal B-of the battery PACK 200 is the negative pole of the battery PACK, the first terminal PACK + of the outlet 300 is the positive pole of the outlet, the second terminal PACK-of the outlet 300 is the negative pole of the outlet, the second terminal B-of the battery PACK 200 is typically connected to the second terminal PACK-of the outlet 300, the second terminal PACK-of the outlet 300 is typically the ground, and the outlet 300 is typically used for connecting a load. In practical application, other components can be connected in series in the connection process of the second end of the battery pack and the second end of the output port, for example, a sampling resistor is connected in series between the second end of the battery pack and the second end of the output port, the sampling resistor is further connected with a control unit, the sampling resistor is used for collecting main loop current and outputting the main loop current to the control unit, the control unit is used for controlling the charge-discharge state of the battery pack according to the main loop current, and the specific connection process and the control process of the control unit can refer to the prior art, and are not limited herein.

In the battery pack management circuit 100, when the battery pack is in a power-on state, first, the first end of the control unit 50 outputs a first control signal to the main switch circuit 10 and the first sampling circuit 20, so that the main switch circuit 10 switches on the connection between the battery pack 200 and the output port 300, and at the same time, the first sampling circuit 20 collects and outputs the voltage of the output port 300 to the second end of the control unit 50, and then, the control unit 50 receives the voltage of the output port, and controls the second sampling circuit 30 not to operate, so that the second sampling circuit 30 is in a standby state. When the battery pack is in a shutdown state, the control unit 50 outputs a fourth control signal to the main switch circuit 10 and the first sampling circuit 20, so that the main switch circuit 10 disconnects the battery pack 200 from the output port 300, and the first sampling circuit 20 does not work, and at this time, the control unit 50 does not receive the voltage of the output port 300, and controls the second sampling circuit 30 to work; then, the second sampling circuit 30 collects the voltage of the battery PACK 200 and outputs the voltage of the battery PACK 200 to the fourth terminal of the control unit 50, and the control unit 50 outputs a discharge signal to the discharge switch 40 according to the voltage of the battery PACK 200, so that the discharge switch 40 turns on the connection between the second terminal of the discharge unit 10 and the second terminal of the output port 300, and thus, the first terminal B + of the battery PACK 200, the discharge unit 60, the second terminal PACK-of the output port 300, and the second terminal B-of the battery PACK 200 form a discharge loop, thereby discharging the battery PACK 200. In the battery pack management circuit 100, the state of charge of the battery can be determined without communication with the fuel gauge, and discharge can be performed according to the state of charge, the structural design is simple, and the production cost is low.

Further, in some embodiments, the control unit is further configured to output a discharge signal to the discharge switch when the voltage of the battery pack is higher than a preset storage voltage value, and control the second sampling circuit not to operate when the voltage of the battery pack is lower than or equal to the preset storage voltage value. By setting a preset value of the storage voltage, when the electric quantity of the battery pack discharges to the preset value or the electric quantity of the battery pack is lower than or equal to the preset value, the control unit can control the second sampling circuit not to work, and therefore the system can be in a low power consumption state.

In some embodiments, referring to fig. 2, the first sampling circuit 20 includes a first switch circuit 21 and a first voltage divider circuit 22. The first end of the first switch circuit 21 is connected to the first end PACK + of the output port 300, the second end of the first switch circuit 21 is connected to the first end of the first voltage divider circuit 22, the third end of the first switch circuit 21 is connected to the first end of the control unit 50, the second end of the first voltage divider circuit 22 is connected to the second end of the control unit 50, the control unit 50 is configured to output a first control signal to the first switch circuit 21, and the first switch circuit 21 is configured to conduct connection between the first end PACK + of the output port 300 and the first end of the first voltage divider circuit 22 according to the first control signal, so that the first voltage divider circuit 22 collects the voltage 300 of the output port and outputs the voltage 300 of the output port to the control unit 50.

In the battery PACK management circuit, when the battery PACK is in the power-on state, the control unit 50 outputs a first control signal to the first switch circuit 21, the first switch circuit 21 switches on the connection between the first end PACK + of the output port 300 and the first end of the first voltage dividing circuit 22, then the first voltage dividing circuit 22 collects the voltage of the output port and outputs the voltage of the output port to the control unit 50, and the control unit 50 receives the voltage of the output port and controls the second sampling circuit 30 not to operate. When the battery PACK is in a shutdown state, the control unit 50 outputs a fourth control signal to the first switch circuit 21, the first switch circuit 21 disconnects the connection between the first end PACK + of the output port 300 and the first end of the first voltage dividing circuit 22 according to the fourth control signal, at this time, the first voltage dividing circuit 22 does not operate, then the first voltage dividing circuit 22 does not acquire the voltage of the output port, and the control unit 50 controls the second sampling circuit 30 to operate.

In some embodiments, with continued reference to fig. 2, the second sampling circuit 30 includes a second switch circuit 31 and a second voltage divider circuit 32. The first end of the second switch circuit 31 is connected to the first end B + of the battery pack 200, the second end of the second switch circuit 31 is connected to the first end of the second voltage divider circuit 32, the third end of the second switch circuit 31 is connected to the third end of the control unit 50, the second end of the second voltage divider circuit 32 is connected to the fourth end of the control unit 50, and the control unit 50 controls the connection or disconnection between the first end of the second switch circuit 31 and the second end of the second switch circuit 31. Specifically, when the control unit 50 receives the voltage at the output port 300, or when the voltage of the battery pack 200 is lower than or equal to the preset stored voltage value, the control unit outputs a second control signal to the second switch circuit 31, so that the second switch circuit 31 disconnects the connection between the first end B + of the battery pack 200 and the first end of the second voltage dividing circuit 32, so that the second voltage dividing circuit 32 does not operate, and when the voltage at the output port 300 is not received, the control unit outputs a third control signal to the second switch circuit 31, so that the second switch circuit 31 connects the connection between the first end B + of the battery pack 200 and the first end of the second voltage dividing circuit 32, and the second voltage dividing circuit 32 collects the voltage of the battery pack and outputs the voltage of the battery pack to the control unit 50.

In the battery pack management circuit, when the battery pack is in a power-on state, the control unit 50 outputs a first control signal to the main switch circuit 10 and the first sampling circuit 20, the first sampling circuit 20 collects the voltage of the output port 300 and outputs the voltage to the second end of the control unit 50, then, the control unit 50 receives the voltage of the output port 300 and outputs a second control signal to the second switch circuit 31, and the second switch circuit 31 disconnects the connection between the first end B + of the battery pack 200 and the first end of the second voltage division circuit 32, so that the second voltage division circuit 32 does not collect the voltage of the battery pack 200. When the battery pack is in a shutdown state, the control unit 50 outputs a fourth control signal to the main switch circuit 10 and the first sampling circuit 20, the first sampling circuit 20 does not operate, at this time, the control unit 50 does not receive the voltage of the output port 300, and outputs a third control signal to the second switch circuit 31, then the second switch circuit 31 switches on the connection between the first end B + of the battery pack 200 and the first end of the second voltage division circuit 32, and the second voltage division circuit 32 collects the voltage of the battery pack and outputs the voltage of the battery pack 300 to the control unit 50 through the second end of the second voltage division circuit 32. Then, if the voltage of the battery pack 300 is higher than the preset stored voltage value, the control unit 50 outputs a discharge signal to the discharge switch 40, and the discharge switch 40 turns on the connection between the second terminal of the discharge unit and the second terminal of the output port according to the discharge signal, thereby discharging the battery pack and lowering the voltage of the battery pack to the preset stored voltage value; if the voltage of the battery pack is lower than or equal to the preset stored voltage value, the control unit 50 outputs a second control signal to the second switch circuit 31, and disconnects the connection between the first terminal B + of the battery pack 200 and the first terminal of the second voltage division circuit 32, so that the second voltage division circuit 32 does not operate, thereby placing the second sampling circuit 30 in a standby state, and reducing the power consumption of the system.

In some embodiments, referring to fig. 3, the first switch circuit 21 includes a first switch Q1, wherein a first end of the first switch Q1 is connected to the first end PACK + of the output port, a second end of the first switch Q1 is connected to the first end of the first voltage divider 22, and a third end of the first switch Q1 is connected to the first end A1 of the control unit 50. Specifically, referring to fig. 3, the first switch Q1 is a first NMOS transistor, wherein a drain of the first NMOS transistor Q1 is connected to the first end PACK + of the output port, a source of the first NMOS transistor Q1 is connected to the first end of the first voltage divider circuit 22, and a gate of the first NMOS transistor Q1 is connected to the first end A1 of the control unit 50. In practical applications, the first switch tube may also be a PMOS tube, a triode, or any other suitable switch device, and the first switch tube is not limited in this embodiment.

In some embodiments, referring to fig. 3 again, the first voltage-dividing circuit 22 includes a first voltage-dividing resistor Rp1 and a second voltage-dividing resistor Rp2, wherein a first end of the first voltage-dividing resistor Rp1 is connected to a second end of the first switch circuit 21, a second end of the first voltage-dividing resistor Rp1 is connected to a second end of the control unit 50 and a first end of the second voltage-dividing resistor Rp2, and a second end of the second voltage-dividing resistor Rp2 is grounded. Specifically, the first end of the first voltage-dividing resistor Rp1 is connected to the source of the first NMOS transistor Q1, and when the first NMOS transistor Q1 is turned on, the first voltage-dividing circuit 22 may collect the voltage at the output port and output the voltage at the output port to the control unit 50 through the second end of the first voltage-dividing resistor Rp 1. In practical applications, the number and the resistance of the voltage dividing resistors of the first voltage dividing circuit 22 can be freely set, and in addition, a digital-to-analog converter can be connected in series between the second end of the first voltage dividing resistor Rp1 and the second end of the control unit 50, which is not limited in this embodiment. It should be noted that in fig. 3 and 4, DGND indicates that the digital ground of the battery management circuit, i.e. the ground of the control unit, differs from the ground of the second side PACK-of the output port.

In order to filter the collected output port voltage, in some embodiments, the battery pack management circuit further includes a first filter circuit, and the first filter circuit is connected in series between the second terminal of the first voltage divider circuit and the second terminal of the control unit. Specifically, referring to fig. 3 again, the first filter circuit is a first capacitor C1, wherein a first end of the first capacitor C1 is connected to a second end of the first voltage-dividing resistor Rp1 and a second end of the control unit 50, respectively, a second end of the first capacitor C1 is grounded, and by providing the first capacitor C1, the output port voltage output by the first voltage-dividing circuit 22 can be filtered, so as to avoid noise from affecting the system operation, and ensure the system reliability. In practical applications, the first capacitor may be replaced by an inductor or any other suitable filter circuit, and the limitation in this embodiment is not required.

In some embodiments, referring to fig. 3, the second switch circuit 31 includes a second switch Q2 and a third switch Q3; the first end of the second switching tube Q2 is connected to the first end B + of the battery pack, the second end of the second switching tube Q2 is connected to the first end of the second voltage dividing circuit 32, the third end of the second switching tube Q2 is connected to the first end of the third switching tube Q3, and the second end of the third switching tube Q3 is connected to the third end of the control unit 50.

Specifically, in some embodiments, the second switching tube Q2 is a PMOS tube, and the third switching tube Q3 is a second NMOS tube; the source electrode of the PMOS transistor Q2 is connected to the first end B + of the battery pack, the drain electrode of the PMOS transistor Q2 is connected to the first end of the second voltage division circuit 32, the gate electrode of the PMOS transistor Q2 is connected to the drain electrode of the second NMOS transistor Q3, the gate electrode of the second NMOS transistor Q3 is connected to the third end of the control unit 50, and the source electrode of the second NMOS transistor Q3 is grounded.

In the battery pack management circuit, when the battery pack is in a power-on state, the first sampling circuit 20 outputs a voltage of an output port to the control unit 50, the control unit 50 outputs a low-level second control signal to a gate of the second NMOS transistor Q3, the second NMOS transistor Q3 is not turned on, at this time, the PMOS transistor Q2 is also not turned on, and the second voltage division circuit 32 does not collect the voltage of the battery pack, that is, the second sampling circuit 30 is in a standby state. When the battery pack is in a shutdown state, the first sampling circuit 20 does not collect the voltage of the output port, and the control unit 50 does not receive the voltage of the output port, at this time, the control unit 50 outputs a high-level third control signal to the gate of the second NMOS transistor Q3, the second NMOS transistor Q3 is turned on, so that the gate of the PMOS transistor Q2 is grounded, and thus the PMOS transistor Q2 is turned on, so that the first end B + of the battery pack and the first end of the second voltage division circuit 32 are connected, the second voltage division circuit 32 collects the voltage of the battery pack and outputs the voltage of the battery pack to the control unit 50, and the control unit 50 performs subsequent control according to the voltage of the battery pack. If the voltage of the battery pack is greater than the preset storage voltage value, the control unit 50 controls the battery pack to perform discharge processing, and if the voltage of the battery pack is less than or equal to the preset storage voltage value, the control unit 50 outputs a low-level second control signal to the grid of the second NMOS transistor Q3 to disconnect the second NMOS transistor Q3, so that the PMOS transistor Q2 is disconnected, the second voltage division circuit 32 does not work, and the system enters a low power consumption state. In practical applications, the second switching tube and the third switching tube may be other types of MOS tubes, triodes, or any other suitable switching devices, and need not be limited in this embodiment.

In some embodiments, the second voltage dividing circuit 32 includes a third voltage dividing resistor Rp3 and a fourth voltage dividing resistor Rp4; a first end of the third voltage-dividing resistor Rp3 is connected to a second end of the second switch circuit 31, a second end of the third voltage-dividing resistor Rp3 is connected to a fourth end of the control unit 50 and a first end of the fourth voltage-dividing resistor Rp4, respectively, and a second end of the fourth voltage-dividing resistor Rp4 is grounded. Specifically, a first end of the third voltage-dividing resistor Rp3 is connected to a drain of the PMOS transistor Q2, and when the PMOS transistor Q2 is turned on, the second voltage-dividing circuit 32 may collect the voltage of the battery pack and output the voltage of the battery pack to the control unit 50 through a second end of the third voltage-dividing resistor Rp 3. In practical applications, the number and the resistance of the voltage dividing resistors of the second voltage dividing circuit 32 can be freely set, and in addition, a digital-to-analog converter can be connected in series between the second end of the third voltage dividing resistor Rp3 and the fourth end of the control unit 50, which is not limited in this embodiment.

In order to filter the collected output port voltage, in some embodiments, the battery management circuit further includes a second filter circuit, and the second filter circuit is connected in series between the second terminal of the second voltage divider circuit and the fourth terminal of the control unit. Specifically, referring to fig. 3, the second filter circuit is a second capacitor C2, wherein a first end of the second capacitor C2 is connected to the fourth end of the control unit 50, a second end of the second capacitor C2 is grounded, and the second capacitor C2 is arranged to filter the battery voltage output by the second voltage dividing circuit 32, so as to prevent noise from affecting the system operation and ensure the system reliability. In practical applications, the second capacitor may be replaced by an inductor or any other suitable filter circuit, and the limitation in this embodiment is not required.

In some embodiments, referring to fig. 3, the discharge switch 40 is a third NMOS transistor Q6; the drain of the third NMOS transistor Q6 is connected to the second end of the discharge unit 60, the source of the third NMOS transistor Q6 is connected to the second end PACK of the output port, and the gate of the third NMOS transistor Q6 is connected to the fifth end of the control unit 50. When the voltage of the battery pack is higher than the preset storage voltage value, the control unit 50 outputs a high-level discharge signal to the gate of the third NMOS transistor Q6 to turn on the third NMOS transistor Q6, so as to turn on the connection between the second end of the discharge unit and the second end of the output port, and place the battery pack in a discharge state; when the voltage of the battery pack is lower than or equal to the preset storage voltage value or the voltage of the battery pack discharges to the preset storage voltage value, the control unit 50 outputs a low level signal to the gate of the third NMOS transistor Q6, so that the third NMOS transistor Q6 is disconnected, thereby disconnecting the connection between the second end of the discharge unit and the second end of the output port, and disconnecting the battery pack discharge loop. In practical application, the discharge switches may be PMOS transistors, triodes, or any other suitable switching devices, and the number of the discharge switches may be set according to actual needs, which is not limited herein.

Further, in some embodiments, referring to fig. 3 again, the discharging unit 60 is a current limiting resistor Rf, the current limiting resistor Rf is connected in series between the first terminal B + of the battery pack and the drain of the third NMOS transistor Q6, and the current limiting resistor Rf is arranged to serve as a discharging unit, so that the power of the battery pack can be consumed, and the magnitude of the discharging current can be limited. In practical application, the number and resistance of the current-limiting resistors Rf may be set according to actual requirements, and the discharging unit may adopt any other circuit structure capable of consuming the battery power, which is not limited herein.

In order to improve the reliability of the system, in some embodiments, please continue to refer to fig. 3, the battery management circuit further includes a first bias resistor R1, a second bias resistor R2, and a third bias resistor R3; the first end of the first biasing resistor R1 is connected with the grid electrode of the second NMOS tube Q3, the second end of the first biasing resistor R1 is grounded, the second biasing resistor R2 is connected between the source electrode of the PMOS tube Q2 and the drain electrode of the PMOS tube Q2 in series, and the third biasing resistor R3 is connected between the source electrode of the third NMOS tube Q6 and the drain electrode of the third NMOS tube Q6 in series. By arranging the bias resistor, the MOS tube can be prevented from generating misoperation under the influence of a noise signal, thereby improving the reliability of the system.

In some embodiments, referring to fig. 3, the main switch circuit 10 includes a fourth NMOS transistor Q4 and a fifth NMOS transistor Q5; the source electrode of the fourth NMOS tube Q4 is connected to the first end B + of the battery PACK, the drain electrode of the fourth NMOS tube Q4 is connected to the drain electrode of the fifth NMOS tube Q5, the source electrode of the fifth NMOS tube Q5 is connected to the second end PACK + of the output port, the gate electrode of the fourth NMOS tube Q4 is connected to the first end A1 of the control unit 50, and the gate electrode of the fifth NMOS tube Q5 is connected to the sixth end A2 of the control unit 50. Like this, can realize the normal charge-discharge of group battery through the MOS pipe of two reverse series connections to because fourth NMOS pipe Q4 and fifth NMOS pipe Q5 all have an internal diode, can prevent that the electric current from flowing backward, make the group battery can be safer when the charge-discharge. In practical applications, the types and the number of the switching tubes of the main switching circuit 10 can be set according to actual requirements, and the first end A1 of the control unit 50 and the sixth end A6 of the control unit 50 can be the same port of the control unit 50 or different ports of the control unit 50, which is not limited in this embodiment.

In some embodiments, referring to fig. 4, the control unit may include a first controller U1 and a second controller U2, and then the first end of the control unit and the sixth end of the control unit are two ports of the first controller U1, respectively, and the second end to the fifth end of the control unit may be four ports of the second controller U2, and the connection manner thereof refers to the above description, and is not repeated herein. The first controller U1 and the second controller U2 may be implemented by a series of micro-control processors STM8, STM16, STM32, or by any other micro-control processor that can receive and output data. Specifically, the second controller U2 can adopt the STM8L050J3 chip, sets up the power supply VCC of second controller U2 to the user manual, and general VCC is 3.3V. In this group battery management circuit, through setting up two controllers, can further reduce the consumption of system, for example when the group battery is in the shutdown state, the accessible sets up and lets first controller get into standby state, only lets the second controller carry out work to can practice thrift the energy consumption.

The specific operation of the battery management circuit according to the present invention will be described in detail with reference to the circuit diagram shown in fig. 4.

When the battery PACK is in a power-on state, firstly, the first controller U1 outputs a first control signal of a high level to the gate of the fourth NMOS transistor Q4 and the gate of the fifth NMOS transistor Q5 of the main switch circuit 10, usually, the driving voltage of the first control signal is higher than the voltage of the first end B + of the battery PACK, at this time, the fourth NMOS transistor Q4 and the fifth NMOS transistor Q5 are both closed, and the battery PACK is conducted with the output port, so that the voltage of the first end PACK + of the output port is equal to the voltage of the first end B + of the battery PACK; since the high-level first control signal is simultaneously output to the first NMOS transistor Q1, the first NMOS transistor Q1 is in a closed state, the pin 8 of the second controller U2 can detect the output port voltage output by the second end of the first voltage-dividing resistor Rp1, and at this time, the second controller U2 judges that the current battery pack is in a power-on state; then, the second controller U2 outputs a low-level second control signal to the gate of the second NMOS transistor Q3, and the second NMOS transistor Q3 is turned off, at this time, the gate of the PMOS transistor Q2 is not grounded, the PMOS transistor Q2 is turned off, the second voltage dividing circuit 32 cannot collect the battery pack voltage, the second controller U2 cannot detect the battery pack voltage, and the second controller U2 is in a standby state.

When the battery pack is in a shutdown state, firstly, the first controller U1 outputs a low-level fourth control signal to the gate of the fourth NMOS transistor Q4, the gate of the fifth NMOS transistor Q5, and the gate of the first NMOS transistor Q1, so that the fourth NMOS transistor Q4, the fifth NMOS transistor Q5, and the first NMOS transistor Q1 are all disconnected, the second voltage division circuit 22 cannot acquire output port voltage, so that the pin 8 of the second controller U2 cannot detect the second end voltage of the first voltage division resistor Rp1, and at this time, the second controller U2 judges that the battery pack is in the shutdown state. Then, after a period set by a user through a program, the second controller U2 outputs a high-level third control signal to the gate of the second NMOS transistor Q3, the second NMOS transistor Q3 is closed, the gate of the PMOS transistor Q2 is grounded, the PMOS transistor Q2 is closed, the second voltage dividing circuit 32 can collect the voltage of the battery pack, the second controller U2 can detect the divided voltage of the second end of the third voltage dividing resistor Rp3, and then calculate the voltage of the corresponding battery pack.

If the voltage of the battery pack is lower than or equal to the preset storage voltage value, the discharging process is not carried out, the second controller U2 outputs a low-level second control signal to the grid electrode of the second NMOS tube Q3, the second NMOS tube Q3 is disconnected, the PMOS tube Q2 is disconnected at the moment, the second controller U2 cannot detect the voltage of the battery pack, and the second controller U2 is in a standby state. If the voltage of the battery pack is greater than the preset storage voltage value, discharge processing is carried out, at the moment, the pin 1 is controlled by the second controller U2 to be changed from a low level to a high level discharge signal, the third NMOS tube Q6 is closed, so that the first end B + of the battery pack is discharged through the current limiting resistor Rf, the second controller U2 always detects the voltage value of the battery pack in the discharge process, once the voltage value of the battery pack is lower than or equal to the preset storage voltage value, the discharge is considered to be finished, finally, the second controller U2 outputs a low level second control signal to the grid electrode of the second NMOS tube Q3, the second sampling circuit is closed to work, and the second controller U2 enters a low power consumption state.

In conclusion, the battery pack management circuit can determine the electric quantity state of the battery without communicating with the fuel gauge, can discharge according to the electric quantity state and is simple in structural design. In addition, the circuit is built by adopting a conventional electronic device and a simple microprocessor, and is easy to design, low in production cost and high in performance-price ratio.

In a second aspect, the present invention provides a battery pack, which includes the battery pack management circuit according to any one of the first aspects. The battery pack can determine the electric quantity state of the battery pack without communicating with an electricity meter, discharge can be carried out according to the electric quantity state, the structural design is simple, and the production cost is low.

The embodiment of the utility model provides a group battery management circuit and group battery, including main switch circuit, first sampling circuit, second sampling circuit, discharge switch, discharge unit and the control unit. When the control unit outputs a first control signal to the main switch circuit and the first sampling circuit, the main switch circuit conducts the connection between the battery pack and the output port, and the first sampling circuit collects and outputs the voltage of the output port to the second end of the control unit; the control unit controls the second sampling circuit to work when not receiving the voltage of the output port, the second sampling circuit collects the voltage of the battery pack and outputs the voltage of the battery pack to the fourth end of the control unit, and the control unit outputs a discharging signal to the discharging switch according to the voltage of the battery pack so as to discharge the battery pack. In the circuit, the battery capacity and the discharge state are determined without communicating with a fuel gauge, and the circuit is simple in design and low in cost.

It should be noted that the above-described device embodiments are merely illustrative, where the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; within the idea of the invention, also technical features in the above embodiments or in different embodiments can be combined, steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A battery management circuit, comprising: the device comprises a main switch circuit, a first sampling circuit, a second sampling circuit, a discharge switch, a discharge unit and a control unit;

2. The battery management circuit of claim 1, wherein the first sampling circuit comprises a first switching circuit and a first voltage divider circuit;

3. The battery management circuit of claim 2, wherein the first switching circuit comprises a first switching tube;

4. The battery management circuit of claim 3, wherein the first switch transistor is a first NMOS transistor;

5. The battery management circuit of claim 2, wherein the first voltage divider circuit comprises a first voltage divider resistor and a second voltage divider resistor;

6. The battery management circuit of claim 1, wherein the second sampling circuit comprises a second switching circuit and a second voltage divider circuit;

7. The battery management circuit of claim 6, wherein the second switching circuit comprises a second switching tube and a third switching tube;

8. The battery pack management circuit according to claim 7, wherein the second switch transistor is a PMOS transistor, and the third switch transistor is a second NMOS transistor;

9. The battery management circuit of claim 6, wherein the second voltage divider circuit comprises a third voltage divider resistor and a fourth voltage divider resistor;

a first end of the third voltage dividing resistor is connected to a second end of the second switch circuit, a second end of the third voltage dividing resistor is connected to a fourth end of the control unit and a first end of the fourth voltage dividing resistor, respectively, and a second end of the fourth voltage dividing resistor is grounded.

10. The battery management circuit according to claim 5 or 9, wherein the battery management circuit further comprises a first capacitor and a second capacitor, a first terminal of the first capacitor is connected to a first terminal of a second voltage-dividing resistor, a second terminal of the first capacitor is connected to ground, a first terminal of the second capacitor is connected to a first terminal of a fourth voltage-dividing resistor, and a second terminal of the second capacitor is connected to ground.

11. The battery management circuit of claim 1, wherein the discharge switch is a third NMOS transistor;

12. The battery management circuit of claim 11, wherein the discharge unit is a current limiting resistor;

13. The battery management circuit of claim 4, 8, 11 or 12, further comprising a first bias resistor, a second bias resistor and a third bias resistor;

the first end of the first bias resistor is connected with the grid electrode of the second NMOS tube, the second end of the first bias resistor is grounded, the second bias resistor is connected between the source electrode of the PMOS tube and the drain electrode of the PMOS tube in series, and the third bias resistor is connected between the source electrode of the third NMOS tube and the drain electrode of the third NMOS tube in series.

14. The battery management circuit of claim 1, wherein the main switching circuit comprises a fourth NMOS transistor and a fifth NMOS transistor;

15. A battery pack comprising the battery management circuit of any of claims 1-14.