CN111384731A

CN111384731A - System and method for battery management and corresponding motor vehicle

Info

Publication number: CN111384731A
Application number: CN201811611406.8A
Authority: CN
Inventors: 陶一枫
Original assignee: Qoros Automotive Co Ltd
Current assignee: Qoros Automotive Co Ltd
Priority date: 2018-12-27
Filing date: 2018-12-27
Publication date: 2020-07-07

Abstract

Embodiments of the present disclosure relate to systems, methods, and corresponding motor vehicles for battery management. The system includes a plurality of battery packs and a switch array including a plurality of switches. Each switch is coupled to a respective battery pack of the plurality of battery packs. The system comprises a boosting module and a storage battery. A boost module is coupled with each switch, and a battery is coupled to the boost module. The system includes a controller coupled to each switch and adapted to close each switch. The controller is coupled to the boost module and adapted to activate the boost module. The switch array is configured to close, by the controller, a respective switch in the switch array coupled to each cell group of the set of cell groups in response to the voltage of each cell group of the set of cell groups in the plurality of cell groups being below a first threshold and the voltage of the storage battery being above a second threshold. The boost module is activated by the controller to communicate each battery pack with the boost module in response to the voltage of each battery pack in the set of battery packs being below a first threshold and the voltage of the storage battery being above a second threshold.

Description

System and method for battery management and corresponding motor vehicle

Technical Field

Embodiments of the present disclosure relate generally to the field of battery management, and more particularly to systems and methods for battery management, and corresponding motor vehicles.

Background

The new energy automobile generally includes a power supply system composed of a battery low voltage and a battery pack high voltage. Because the battery pack is composed of a plurality of battery packs, along with the gradual power consumption of the battery packs in the running process of a vehicle, the situation that the voltages of the battery packs are inconsistent inevitably occurs after a period of time. It is a challenge for designers to keep the voltage of the battery pack as uniform as possible during power consumption and charging.

The existing products generally solve the problem through a scheme of passive equalization and active equalization, but both schemes have disadvantages. In the scheme of passive equalization, the battery pack which reaches the preset voltage firstly keeps the voltage consistent with other battery packs through self charging and discharging. But this solution is inefficient. For the active equalization scheme, the battery pack which reaches the predetermined voltage firstly charges other battery packs to seek voltage consistency, however, the use of the active equalization scheme in each battery pack also greatly increases the cost of the whole system, and is often limited in the actual use process.

Disclosure of Invention

As noted above, there is a need for an improved battery management system to optimize battery allocation in a motor vehicle to maximize the utilization of a battery pack.

Embodiments of the present disclosure provide a system, method, and motor vehicle including the same for battery management, which are intended to address, at least in part, the above and/or other potential problems with current vehicle designs.

In a first aspect, embodiments of the present disclosure provide a system for battery management. The system comprises: a plurality of battery packs; a switch array comprising a plurality of switches, wherein each switch is configured to be respectively coupled with a respective battery pack of the plurality of battery packs; a boost module configured to couple with each switch in the switch array; a battery configured to be coupled to the boost module; and a controller configured to be coupled to each switch in the array of switches and adapted to close said each switch, the controller further configured to be coupled to the boost module and adapted to activate the boost module; wherein the switch array is configured to: responsive to the voltage of each cell pack of a set of cell packs in the plurality of cell packs being below a first threshold and the voltage of the storage battery being above a second threshold, closing, by the controller, a respective switch of the switch array coupled to each cell pack of the set of cell packs; and wherein the boost module is further configured to: responsive to the voltage of the each battery pack in the set of battery packs being below the first threshold and the voltage of the battery being above the second threshold, initiating by the controller to communicate the each battery pack with the boost module.

According to the embodiment of the disclosure, the storage battery and the battery pack can be interacted, so that the battery pack with lower voltage in the system is charged by the storage battery first, and thus the voltage of the battery pack in the system can be kept balanced to the maximum extent.

In some embodiments, the system further comprises a voltage reduction module configured to be coupled to the battery and the plurality of battery packs, wherein the voltage reduction module is further configured to be activated by the controller in response to the voltage of the battery being below a third threshold, thereby causing the plurality of battery packs to charge the battery via the voltage reduction module.

In some embodiments, each of the plurality of switches comprises a positive part and a negative part, wherein the positive part and the negative part are closed simultaneously to enable communication of each battery pack of the set of battery packs with the boost module.

In some embodiments, the switch array is a relay or a MOS transistor.

In some embodiments, the power of the buck module is greater than the power of the boost module.

In some embodiments, the voltage boost module and the voltage buck module are disposed on a power isolation module.

In a second aspect, embodiments of the present disclosure provide a method for battery management. The method comprises the following steps: providing a plurality of battery packs; providing a switch array comprising a plurality of switches, wherein each switch is configured to be respectively coupled with a respective battery pack of the plurality of battery packs; providing a boost module configured to couple with each switch in the switch array; providing a battery configured to be coupled to the boost module; providing a controller configured to be coupled to each switch in the array of switches and adapted to close the each switch, the controller further configured to be coupled to the boost module and adapted to activate the boost module; responsive to the voltage of each cell pack of a set of cell packs in the plurality of cell packs being below a first threshold and the voltage of the storage battery being above a second threshold, closing, by the controller, a respective switch of the switch array coupled to each cell pack of the set of cell packs; and responsive to the voltage of the each battery pack in the set of battery packs being below the first threshold and the voltage of the battery being above the second threshold, activating, by the controller, the boost module to communicate the each battery pack with the boost module.

In a third aspect, embodiments of the present disclosure provide a motor vehicle. The motor vehicle comprises a system for battery management according to the first aspect of the present disclosure.

In some embodiments, the battery of the motor vehicle at least powers starting of the motor vehicle and the plurality of battery packs at least powers traveling of the motor vehicle.

In some embodiments, the motor vehicle is a pure electric vehicle or a hybrid electric vehicle.

Drawings

The above and other objects, features and advantages of the embodiments of the present disclosure will become more readily understood through the following detailed description with reference to the accompanying drawings. Various embodiments of the present disclosure will be described by way of example and not limitation in the accompanying drawings, in which:

FIG. 1 shows a schematic side view of a motor vehicle according to an exemplary embodiment of the present disclosure;

FIG. 2 shows a schematic diagram of the battery management system provided on the motor vehicle in FIG. 1; and

fig. 3 shows a flowchart of a method for battery management according to an exemplary embodiment of the present disclosure.

Detailed Description

The principles of the present disclosure will now be described with reference to various exemplary embodiments shown in the drawings. It should be understood that these examples are described merely to enable those skilled in the art to better understand and further implement the present disclosure, and are not intended to limit the scope of the present disclosure in any way. It should be noted that where feasible, similar or identical reference numerals may be used in the figures and that similar or identical reference numerals may indicate similar or identical functions. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

Since the charging and discharging performance of the battery depends greatly on the voltage of the battery pack with lower voltage in the system, how to equalize the voltages of the battery packs in the system to the maximum extent is a challenge for designers of battery management systems. The battery pack with lower voltage can be charged preferentially by introducing the storage battery, so that the voltage difference of each battery pack in the system is reduced, and the system can be prevented from being greatly improved, thereby saving the overall cost of the system.

The structure of the battery management system 100 according to an exemplary embodiment of the present disclosure will now be described in detail with reference to fig. 1 to 2. It is to be noted that in the description herein, it is possible to use a "new energy vehicle" as an example of the motor vehicle 1. However, the scope of the present disclosure is not limited thereto, and any motor vehicle 1 capable of employing the battery management system 100 described herein is encompassed within the scope of the present disclosure.

In general, as shown in fig. 2, the system 100 for battery management described herein includes a plurality of battery packs 104 and a switch array 106. A plurality of switches are provided in the switch array 106, as shown in fig. 2, wherein each switch is coupled to a respective battery pack of the plurality of battery packs 104. The system 100 also includes a boost module 108, the boost module 108 being coupled to the plurality of switches in the switch array 106. The system 100 also includes a battery 102. The battery 102 is coupled to the boost module 108.

The system 100 also includes a controller (not shown) coupled to each switch in the switch array 106 and adapted to close each switch. Further, the controller is also configured to be coupled to the boost module 108 and adapted to activate the boost module 108.

In the case where the battery pack 104 in the system 100 is fully charged, the voltage of the battery pack 104 is equal to or slightly lower than its maximum voltage. As the battery pack 104 operates, the voltage of the battery pack 104 will gradually decrease. When the voltage of a certain battery pack 104 is first below a predetermined first threshold (at this time, the battery pack 104 is the lowest voltage battery pack), and if the voltage of the storage battery 102 is above a predetermined second threshold at this time, the controller will control the switch coupled to the battery pack 104 to close and control the boost module 108 to start. In this way, the battery 102 is communicated with the battery pack 104 with the lowest voltage through the boost module 108 and the corresponding switch in the switch array 106. The voltage of the battery 102 may be boosted to a suitable voltage by the boost module 108 to charge the battery pack 104 having the lowest voltage.

When the battery 102 charges the battery pack 104 with the lowest voltage, the voltages of other battery packs 104 may also decrease below the first threshold due to consumption. That is, there are a plurality of battery packs 104 in the system 100 at this time that satisfy the condition of being lower than the first threshold value. These battery packs 104 constitute a battery pack assembly 105. In response, a respective plurality of switches in the switch array 106 coupled to each cell in the set of cells 105 are closed, and each cell in the set of cells 105 is in communication with the boost module 108 as a result of the boost module 108 being activated, such that the battery 102 charges each cell in the set of cells 105 through the boost module.

According to an embodiment of the present disclosure, since the battery 102 may charge one or more battery packs 104 having a lower voltage first, the voltage difference between the battery pack 104 and other battery packs having a relatively higher voltage is reduced. In this way, the voltage of the battery pack 104 in the system 100 can be kept as uniform as possible by a low-cost method, thereby maximizing the utilization rate of the battery pack 104.

In some embodiments, the controller may also acquire the voltages of the battery pack 104 and the storage battery 102 and compare the acquired voltages with a first threshold and a second threshold, respectively. In some embodiments, the controller may be an integrated controller. In some embodiments, the controller may also be a discrete controller, each discrete module being used to implement a different function.

In some embodiments, the first threshold may be a voltage of a voltage plateau of the system 100. It will be understood that the first threshold may be changed accordingly according to actual circumstances, and the specific value thereof is not limited by the embodiments of the present disclosure. For example, in a voltage plateau of lithium iron phosphate, the first threshold value may be 3.2V. In the plateau of lithium cobaltate, the first threshold may be 3.7V.

The second threshold value may be determined by simulation or through experiment, or may be determined according to the experience of the user. For example, the second threshold may be 10.8V under the condition that the rated voltage of the battery 102 is 12V. It is to be understood that the numerical values herein are exemplary only and are not limiting. The second threshold may be other values greater than or less than 10.8V, as long as the determination of the value optimizes the operating efficiency of the battery management system 100.

In alternative embodiments, other factors may be further considered in determining whether to turn on boost system 108 and close the corresponding switches of switch array 106, so long as such considerations favor the overall operation of system 100. For example, in addition to considering the voltage of the battery 102 and the voltage of the battery pack 104 and the magnitude of the threshold, it may be considered whether the maximum difference between the maximum cell voltages of the battery pack of the lowest cell voltage and the other battery packs exceeds a certain predetermined threshold. In an alternative embodiment, the operation of the array switch 106 may be stopped if the lowest cell voltage difference of the respective battery packs is below the predetermined threshold. In some embodiments, the predetermined threshold may be 200 mV.

In some embodiments, the system 100 may also include a voltage reduction module 110. As shown in fig. 2, the buck module 110 is coupled to the battery 102 and the plurality of cell stacks 104.

When the boost module 108 is turned on, the buck module 110 will also be activated if the voltage of the battery 102 is below some predetermined threshold. This indicates that the voltage of the battery 102 is too low and needs to be charged. As the voltage dropping module 110 is activated, the voltages of the plurality of battery stacks 104 are dropped to appropriate voltages via the voltage dropping module 110, thereby charging the secondary battery 102. As mentioned above, the predetermined threshold value may be determined by simulation or experiment, or may be determined empirically.

In this way, with the system 100 for battery management according to the embodiment of the present disclosure, the secondary battery 102 and the battery pack 104 may be charged and discharged. On one hand, the battery 102 is charged by the voltage reduction module 110 with the electric power taken from the battery pack 104; on the other hand, the battery 102 supplements power to some of the plurality of battery packs 104 through the boost module 108. Through such cyclical interaction, the battery 102 is incorporated into the battery management system 100. Based on the existing configuration, the battery pack can exert the maximum electric quantity, so that the service cycle of the battery pack is prolonged.

In some embodiments, the battery packs 104 in the system 100 may be divided into a plurality of battery packs, each battery pack including a plurality of battery packs 104. The boost module 108 and the buck module 110 may interact with the battery pack to increase the life cycle of the battery pack.

In some embodiments, as shown in FIG. 2, each of the plurality of switches may include a positive component 107-1 and a negative component 107-2. In response to control by the controller, the positive and negative parts 107-1 and 107-2 of the switches corresponding to the battery packs in the battery pack collection 105 may be closed simultaneously to enable communication of these battery packs with the boost module 108.

In some embodiments, the switch array 106 may be a relay or a MOS transistor.

In some embodiments, the power of the buck module 110 may be greater than the power of the boost module 108. In this manner, the battery 102 may be charged at a rate higher than the discharge rate while the battery pack 104 is being charged, which may ensure that the battery 102 may still be charged by a controller coupled to the battery 102, thereby not affecting the normal operation of the battery 102.

In some embodiments, the boost module 108 and the buck module 110 may be disposed on the power isolation module. The power isolation module can be built by a manufacturer through a chip, and can also be realized by purchasing a mature power isolation system available on the market. In this way, the applicability of the system 100 may be increased.

In a second aspect, embodiments of the present disclosure provide a method 300 for battery management. The method 300 will be described below in conjunction with fig. 3.

At block 302, a plurality of battery packs 104 are provided. At block 304, a switch array 106 is provided, the switch array 106 including a plurality of switches, wherein each switch is configured to be respectively coupled with a respective battery pack of the plurality of battery packs 104. At block 306, a boost module 108 is provided, the boost module 108 configured to couple with each switch in the switch array 106. At block 308, the battery 102 is provided, the battery 102 configured to be coupled to the boost module 108. At block 310, a controller is provided that is configured to be coupled to each switch in the switch array 106 and adapted to close each switch, the controller further configured to be coupled to the boost module 108 and adapted to activate the boost module 108. At block 312, responsive to the voltage of each cell pack of the set of cell packs 105 in the plurality of cell packs 104 being below the first threshold and the voltage of the storage battery 102 being above the second threshold, a respective switch of the switch array 106 coupled to each cell pack of the set of cell packs 105 is closed by the controller. At block 314, the boost module 108 is activated by the controller to communicate each battery pack with the boost module 108 in response to the voltage of each battery pack in the set 105 of battery packs being below the first threshold and the voltage of the battery 102 being above the second threshold.

It will be appreciated that the various arrangements and structures referred to in figure 3 have been described above with reference to figures 1 to 2 and will not be described again here.

In a third aspect, embodiments of the present disclosure provide a motor vehicle 1. The motor vehicle 1 comprises a system 100 for battery management according to the first aspect of the present disclosure. In some embodiments, the motor vehicle 1 may comprise a plurality of battery packs, wherein each battery pack may comprise a plurality of battery packs 104 as described above.

In this way, according to the embodiment of the present disclosure, the voltage can be equalized among the battery pack 104, the battery pack, and the storage battery 102, thereby maximizing the utilization rate of the battery.

Furthermore, the accumulator 102 in the motor vehicle 1 can serve as a backup power source for the battery pack, whereby the mileage of the motor vehicle 1 can be increased in an emergency situation in which the battery pack 104 in the motor vehicle 1 is about to run out. The motor vehicle 1 can travel to a nearby charging station for charging by means of the amount of electricity in the storage battery 102 charged to the battery pack 104, thereby avoiding expenses and time costs due to road rescue.

In addition, the above arrangement can function in various operating states of the motor vehicle 1. For example, the above-described functions can be activated during stationary charging and during driving of the motor vehicle 1.

In some embodiments, the battery 102 of the motor vehicle at least powers the starting of the motor vehicle 1, and the plurality of battery packs 104 at least powers the traveling of the motor vehicle 1. It will be appreciated that the battery 102 may also provide other functions for the operation of the motor vehicle 1. The battery 102 may power the cigarette lighter of the motor vehicle 1, to name a few. The battery 102 may also provide power for the lighting of the motor vehicle 1.

In some embodiments, the motor vehicle 1 may be a pure electric vehicle or a hybrid electric vehicle. The motor vehicle 1 may be an existing vehicle or a motor vehicle developed in the future that is suitable for using the battery management system 100 according to the embodiment of the present disclosure.

It is noted that, as used herein, the term "include" and its variants mean open inclusion, i.e., "including but not limited to". Unless specifically stated otherwise, the term "or" means "and/or". The term "coupled" includes "directly coupled without the aid of intermediate components" and "indirectly coupled with the aid of intermediate components". The terms "first," "second," and the like may refer to different or the same object. Other explicit and/or implicit definitions may also be included below. Furthermore, the numerical values set forth herein are also exemplary only, and not limiting. These values may be modified without departing from the scope of embodiments of the present disclosure. Additionally, in the following claims, although only some features are recited in certain claims, it should be understood that these features may be combined with features recited in all other claims without departing from the scope of the embodiments of the present disclosure.

Although claims have been formulated in this application to particular combinations of features, it should be understood that the scope of the disclosure also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalisation thereof, whether or not it relates to the same aspect as presently claimed in any claim.

Claims

1. A system (100) for battery management, comprising:

a plurality of battery packs (104);

a switch array (106) comprising a plurality of switches, wherein each switch is configured to be respectively coupled with a respective battery pack of the plurality of battery packs (104);

a boost module (108) configured to couple with each switch in the switch array (106);

a battery (102) configured to be coupled to the boost module (108); and

a controller configured to be coupled to each switch in the switch array (106) and adapted to close said each switch, the controller further configured to be coupled to the boost module (108) and adapted to activate the boost module (108);

wherein the switch array (106) is configured to: responsive to the voltage of each cell group of a set (105) of cell groups of the plurality of cell groups (104) being below a first threshold and the voltage of the storage battery (102) being above a second threshold, closing, by the controller, a respective switch of the switch array (106) coupled to each cell group of the set (105) of cell groups; and is

Wherein the boost module (108) is further configured to: responsive to the voltage of the each battery pack in the set (105) of battery packs being below the first threshold and the voltage of the battery (102) being above the second threshold, activating by the controller to communicate the each battery pack with the boost module (108).

2. The system (100) of claim 1, further comprising:

a voltage reduction module (110) configured to be coupled to the battery (102) and the plurality of battery packs (104), wherein the voltage reduction module (110) is further configured to be activated by the controller in response to the voltage of the battery (102) being below a third threshold, thereby causing the plurality of battery packs (104) to charge the battery (102) via the voltage reduction module (110).

3. The system (100) of claim 1, each switch of the plurality of switches comprising a positive component (107-1) and a negative component (107-2), wherein the positive component (107-1) and the negative component (107-2) are closed simultaneously to enable communication of each battery pack of the battery pack collection (105) with the boost module (108).

4. The system (100) of claim 1, wherein the switch array (106) is a relay or a MOS transistor.

5. The system (100) of claim 2, wherein the power of the buck module (110) is greater than the power of the boost module (108).

6. The system (100) of claim 2, wherein the step-up module (108) and the step-down module (110) are disposed on a power isolation module.

7. A method for battery management, comprising:

providing a plurality of battery packs (104);

providing a switch array (106), the switch array (106) comprising a plurality of switches, wherein each switch is configured to be respectively coupled with a respective battery pack of the plurality of battery packs (104);

providing a boost module (108), the boost module (108) configured to be coupled with each switch in the switch array (106);

providing a battery (102), the battery (102) configured to be coupled to the boost module (108);

providing a controller configured to be coupled to each switch in the switch array (106) and adapted to close said each switch, the controller further configured to be coupled to the boost module (108) and adapted to activate the boost module (108);

responsive to the voltage of each cell group of a set (105) of cell groups of the plurality of cell groups (104) being below a first threshold and the voltage of the storage battery (102) being above a second threshold, closing, by the controller, a respective switch of the switch array (106) coupled to each cell group of the set (105) of cell groups; and

activating, by the controller, the boost module (108) to communicate the each battery pack with the boost module (108) in response to the voltage of the each battery pack in the set of battery packs (105) being below the first threshold and the voltage of the battery (102) being above the second threshold.

8. A motor vehicle (1) comprising a system (100) for battery management according to any one of claims 1 to 6.

9. A motor vehicle (1) according to claim 8, wherein the battery (102) powers at least the starting of the motor vehicle (1) and the plurality of battery packs (104) powers at least the travelling of the motor vehicle (1).

10. Motor vehicle (1) according to claim 8, the motor vehicle (1) being a pure electric vehicle or a hybrid electric vehicle.