TW201325022A - Charge management system and charger using the same - Google Patents

Abstract

The invention provides a charge management system which includes a first signal output interface, a second signal output interface, a third signal output interface, and a controller electrically connected with the first, second and third signal output interface. It has two kinds of work modes, the first mode: through the first charging current control signal and the second charging current control signal to work the charger with combined control, reaching the goal of switch fast charging, trickle charging, and stop charging function according to the battery status; the second mode: through the variable third charging current control signal, reaching a current variable charge and gain a higher charging efficiency. The invention of the charge management system can be set up in different kinds of the charger, so that charger with different working modes can charge the battery with charge management system effectively.

Description

Charge management system and charger using the same

The invention belongs to the field of batteries, and particularly relates to a charging management system for controlling charging of a battery, and a charger using the charging management system.

The battery management system is usually responsible for the calculation of battery power in the battery pack, battery protection, battery balance control between batteries, and signal communication inside and outside the battery management system. In the prior art, products that generally use batteries are required to be controlled with a battery management system.

Since it is difficult to ensure complete uniformity in the manufacturing process of the battery, there is a difference in charging or discharging characteristics between the battery cells connected in series. Therefore, when using a battery pack of a series battery unit, there is a problem that when charging, in some battery units, even if some battery units are overcharged, some battery units are still not saturated; or when discharging In the same battery pack, some battery cells have not been completely discharged, but some battery cells are still over-discharged. Further, if the battery cells are excessively discharged/charged for a long period of time, significant deterioration may occur in the materials constituting the battery cells, so that the characteristics of the battery cells become different, and such deterioration is one of the causes of the difference between the battery cells.

There are two main methods for balancing the current power. One of them is passive power balance, which means that the excess power in the battery unit is dissipated into heat by resistance and can only be performed during charging. The other is active battery balancing, which uses energy transfer to transfer excess power from the battery pack to a low-capacity battery unit, and can be performed while the battery is charging, discharging, and not operating.

In the battery management system of electric bicycles and electric motorcycles in general, due to cost considerations, passive battery balancing is often used to balance the power between batteries/batteries, and it is necessary to periodically collect each The voltage, current, temperature and other parameters of the battery are used to complete the balance.

Generally, when the charger charges the battery, it can be divided into two modes: one is normal charging, that is, the battery is quickly charged with a larger current, and then the battery is operated with a smaller current when the battery is near saturation. Charging, that is, trickle charging, this charging method often requires two charging interfaces to switch; the other is variable current charging, that is, only one charging interface is required to charge the battery with different currents.

However, in a passive battery balancing battery management system, since there is often no communication with an external charger, a charging mode set by the battery management system is often not applicable to a charger using another charging mode.

Furthermore, since the charger technology focuses on the direction of the battery management system technology, the general battery manufacturer does not produce the charger by itself, and the charger supplier cannot flexibly meet the different charging functions required by the battery management system. In view of this, it is necessary to modify the design of the conventional charger to solve the above problems.

It is an object of the present invention to provide a charging management system that can be placed in a charger of a different mode so that chargers of different operating modes can be effectively charged to a battery system having a battery management system.

It is also an object of the present invention to provide a charger employing the charging management system.

According to an embodiment of the present invention, a charging management system is provided for receiving a signal from a battery being charged, and controlling a charging circuit disposed in the charger to charge the charged battery according to the signal, the charging management system The first signal output interface is configured to output a control signal for characterizing the first charging current to the charging circuit, and the second signal output interface is configured to output a control signal for characterizing the second charging current to the charging circuit, the second charging current The value is less than the first charging current value; the third signal output interface is configured to output a control signal indicative of the variable third charging current to the charging circuit; and the controller, and the first, second, and third signal output interfaces Electrically connecting, the controller is configured to control the charging management system to work in at least one of the following two modes: in the first mode, the controller selectively controls the first signal output interface or the second signal output interface to output a control signal; In the second mode, the controller only controls the third signal output interface to output the control signal.

In an embodiment of the invention, in the first mode, the controller is further configured to simultaneously control the first signal output interface and the second signal output interface to not output the control signal.

In an embodiment of the present invention, in the first mode, the controller is further configured to first control the first signal output interface to output a control signal, and then control the second signal output interface to output a control signal.

In a specific embodiment of the present invention, the charging management system further includes a first switch disposed between the controller and the first signal output interface, and a second switch disposed between the controller and the second signal output interface The controller controls the first signal output interface or the second signal output interface to output/not output the control signal correspondingly by controlling the on/off of the first or second switch.

In a specific embodiment of the invention, the first switch and the second switch each comprise an optical coupling relay.

In an embodiment of the invention, in the second mode, the controller is configured to control the output of the third signal output interface by outputting a Pulse Width Modulation (PWM) signal to the third signal output interface.

In a specific embodiment of the present invention, the charging management system further includes a signal input interface for receiving a communication signal from the rechargeable battery; the controller is further configured to capture a signal input by the signal input interface, and Controlling the output of the first, second, or third signal output interface according to the signal.

In a specific embodiment of the invention, the charge management system further includes a power interface for receiving power from the battery being charged, and a voltage conversion circuit coupled between the power interface and the controller.

In a specific embodiment of the invention, the positive and negative terminals of the power interface each include two conductive terminals.

According to another embodiment of the present invention, a charger is provided, the charger comprising: a charging management system as described above; and a charging circuit for receiving a control signal from the charging management system, and according to the control The signal corresponds to the output charging current.

Through the above embodiments, the present invention can have the following effects: providing a charging management system capable of operating in at least two different operating modes, wherein the first mode is adopted for a charger that can only recognize the digital switching amount: The control signal characterizing the first charging current and the control signal characterizing the second charging current are combined to control the charger to switch between the functions of fast charging, trickle charging, and stopping charging; for the identifiable analog quantity The charger adopts a second mode, that is, a current variable charging mode of the charger by characterizing a control signal of a variable third charging current to achieve higher charging efficiency. With this arrangement, it is possible to efficiently charge the battery system having the battery management system to the battery system having the battery management system without modifying the design of the battery management system in the battery.

The above summary, the following detailed description and the annexed drawings are intended to further illustrate the manner, the Other objects and advantages of the present invention will be described in the following description and drawings.

The present invention will be described in detail below in conjunction with the embodiments shown in the drawings. However, the embodiments are not intended to limit the invention, and the structures, methods, or functional changes made by those skilled in the art in accordance with the embodiments are included in the scope of the present invention.

Referring to the first figure, in the embodiment of the present invention, the battery to be charged refers to the battery system 400, and the battery system 400 includes a battery management system 42 and a battery 41 having a plurality of battery cells connected in series with each other. In an alternative embodiment, the plurality of battery units may also be divided into a plurality of battery modules, and the number of battery units included in different battery modules may be the same or different.

A specific embodiment of the charging management system of the present invention will be described with reference to the first and second figures. The charging management system 100 is disposed in the charger 200 for receiving signals from the battery system 400, and controls the charging circuit 300 disposed in the charger 200 to charge the battery that needs to be charged according to the signal.

The charging management system includes: a first signal output interface 11, a second signal output interface 12, a third signal output interface 13, and a controller 14.

The first signal output interface 11, the second signal output interface 12, and the third signal output interface 13 are both used to output a charging current control signal indicating a certain current value to the charging circuit 300, so that the charging circuit 300 selects charging currents of different sizes. The battery 41 in the battery system 400 is charged. The difference is that the first signal output interface 11 is configured to output a control signal for characterizing the first charging current to the charging circuit 300, and the second signal output interface 12 is configured to output a control signal for characterizing the second charging current to the charging circuit 300, and The second charging current value is smaller than the first charging current value; the third signal output interface 13 is configured to output a control signal indicative of the variable third charging current to the charging circuit 300.

In this embodiment, the second charging current value is much smaller than the first charging current value, and the first charging current is used for fast charging when the battery 41 is generally charged, and a larger current value can obtain a better charging rate. To increase the charging efficiency; and the second charging current is used to trickle charge the battery 41, at which time the charging current charges the nearly saturated battery unit.

The magnitude of the third charging current value may vary depending on the condition of the battery being charged. For example, when the battery starts to charge, the third charging current is maintained at a relatively high current level for rapid charging, and when a part of the battery cells in the battery first reaches saturation, the third charging current value is lowered, and thus the third is continuously lowered. The charging current value is until the battery 41 is fully charged. The reason for this is that when charging, the voltage value Vcell of the battery 41 detected by the battery management system 42 in the battery system 400 is substantially composed of two parts, one part is the voltage Vcap of the battery of the battery 41, and the other part is due to the battery 41. The internal resistance of the cell produces a voltage difference Vres, that is, Vcell=Vcap+Vres, and the larger the charging current, the larger the voltage difference Vres due to the internal resistance of the cell.

In a specific embodiment, for example, when the battery is charged with a current of 100 A, the voltage of the battery 41 is detected to be 3.8 V. If the current is reduced to 2 A, the battery is charged, and the voltage of the battery 41 is detected to drop to 3.5V. Obviously, the larger the charging current, the more accurately the detected battery voltage value can accurately reflect the actual charging condition of the battery. Therefore, only by continuously reducing the third charging current value can the effect of Vres on the battery voltage detection be minimized to ensure the battery charging. Reliability, improve charging efficiency.

The controller 14 is electrically connected to the first, second, and third signal output interfaces 11, 12, and 13 and controls the charging management system 100 to operate at least in one of the first mode and the second mode.

The controller 14 may include a microprocessor (MCU), which may include a central processing unit (CPU), a read-only memory (ROM), and a random access memory (random access memory). RAM), timing module, digital analog conversion module (A/D converter), and complex input/output ports. Of course, the controller 14 can also adopt other forms of integrated circuits, such as an Application Specific Integrated Circuit (ASIC) or a Field Programmable Gate Array (FPGA).

The first mode and the second mode mentioned here are respectively corresponding to the two main types of chargers. Of course, in other embodiments, more modes may be set to correspond to more types of chargers.

If the charger can only recognize the switching signal, it corresponds to the first mode, and the controller 14 selectively controls the first signal output interface 11 or the second signal output interface 12 to output the control signal. Specifically, when the battery 41 is just beginning to be charged, the controller 14 first controls the first signal output interface 11 to output a first charging current control signal, and at this time, performs charging of a larger current to obtain a fast charging effect. When the battery management system 42 detects that the battery 41 is nearly saturated, the communication signal of the battery 41 is transmitted to the charging management system 100 through the signal input interface 16; subsequently, the controller 14 controls the communication signal according to the captured battery 41. The second signal output interface 12 outputs a second charging current control signal. At this time, the charger 300 performs trickle charging on the battery 41.

In an alternative embodiment, in the first mode, when the battery management system 42 detects that the battery 41 is saturated, the controller 14 can also control whether the first signal output interface 11 and the second signal output interface 12 do not output control signals. That is, at this time, the charging circuit 300 stops charging the battery 41.

In a specific circuit, the charging management system 100 further includes a first switch 151 disposed between the controller 14 and the first signal output interface 11, and a second disposed between the controller 14 and the second signal output interface 12. Switch 152. The controller 14 controls the first signal output interface 11 or the second signal output interface 12 to output/not output control signals correspondingly by controlling the on/off of the first or second switches 151, 152.

As is well known to those skilled in the art, the first switch 151 and the second switch 152 may include a triode, a thyristor, a relay switch, or a metal oxide semiconductor field effect transistor (MOSFET). Switch form. In this embodiment, the first switch 151 and the second switch 152 include optical coupling relays P1-A, P1-B, and control the turn-off or closing of the MOSFETs in the optical coupling relays P1-A, P1-B to achieve control A switch 151 and a second switch 152 are turned on/off.

If the charger can recognize the analog quantity control signal, it corresponds to the second mode, at which time the controller 14 only controls the third signal interface 13 to output the control signal. Specifically, the controller 14 controls the output of the third signal output interface 13 by outputting a pulse width modulation (PWM) signal to the third signal output interface 13, and the pulse width modulation signal can be connected to the controller 14 by The amplifier 19 between the third signal interface 13 and the third signal interface 13 is amplified to ensure the accuracy of the charging control.

When the battery 41 starts charging, the controller 14 controls the third signal output interface 13 to output a control signal of the third charging current, and performs rapid charging of a larger current. When the battery management system 42 detects the voltage of the battery 41 or the voltage of some of the battery cells in the battery 41 reaches saturation, a corresponding communication signal is generated and transmitted to the charging management system 100 through the signal input interface; subsequently, the controller 14 is based on the captured The communication signal controls the third signal output interface 13 to output a third charging current whose current value is slightly lowered. At this time, since the third charging current is lowered, the voltage difference generated by the internal resistance of the cell is lowered, and the battery cell that originally detected saturation is detected to be unsaturated and can continue to be charged. The value of the third charging current is continuously lowered until the voltage of the battery 41 does not decrease with the decrease of the third charging current, or the voltage value decreased by the decrease of the third charging current is less than a certain threshold.

In the present embodiment, the charge management system 100 further includes a power interface 17 and a voltage conversion circuit 18. The power interface 17 is for receiving power from the battery system 400; the voltage conversion circuit 18 is coupled between the power interface 17 and the controller 14. Thus, the power required for the entire charge management system 100 including the controller 14 to operate is provided by the battery system 400, and the voltage conversion circuit 18 outputs the battery 41 through the DC/DC converter 181 and the voltage stabilizing circuit therein. The current step-down regulator is the smaller operating current required by the charge management system 100. The benefit of this is that the charger manufacturer can eliminate the need to design additional power supply circuits for the charge management system 100, reducing design and manufacturing costs.

As a preferred embodiment, the positive electrode 171 and the negative electrode 172 of the power supply interface 17 each include two conductive terminals. That is to say, the function of J1-4 and terminal J1-3 in the terminal of the positive electrode 171 is the same, and the function of the terminal J1-2 and the terminal J1-1 in the negative electrode 172 is the same, in order to ensure that a certain terminal is damaged, the charging management system It still works normally to prevent damage to the battery management system 42.

Although the battery management system exemplified in the above embodiment adopts a passive battery balancing mode, in other embodiments, the battery management system can also perform active battery balancing.

In a specific embodiment of the charger 200 of the present invention, the charging management system 100 described in the above embodiment is used, and the charging management system 100 is connected to the charging circuit 300, and the charging circuit 300 receives the charging circuit 300. The control signal of the charging management system 100 outputs a corresponding charging current to charge the battery system 400.

It can be seen from the above embodiments that a charging management system is provided which is capable of operating in at least two different modes of operation, wherein for a charger that can only recognize a digitally switched amount, a first mode is employed: by characterizing the control of the first charging current The signal and the control signal representing the second charging current are combined and controlled to switch between the functions of fast charging, trickle charging, and stopping charging; for the charger capable of recognizing the analog quantity, the second mode is adopted. That is, by characterizing the control signal of the variable third charging current, the charger is subjected to a current variable charging mode to achieve higher charging efficiency. With this arrangement, it is possible to efficiently charge the battery system having the battery management system to the battery system having the battery management system without modifying the design of the battery management system in the battery.

It is apparent to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments are to be considered as illustrative and not restrictive, and the scope of the invention is defined by the scope of the appended claims rather than the description All changes in the meaning and scope of equivalents of the patent range are encompassed by the invention. Any reference signs in the scope of the patent application should not be construed as limiting the scope of the claimed patent.

In addition, it should be understood that although the description is described in terms of embodiments, not every embodiment includes only one independent technical solution. The description of the specification is merely for the sake of clarity, and those skilled in the art should In general, the technical solutions in the various embodiments may also be combined as appropriate to form other embodiments that can be understood by those skilled in the art.

100. . . Charging management system

11. . . First signal output interface

12. . . Second signal output interface

13. . . Third signal output interface

14. . . Controller

151. . . First switch

152. . . Second switch

16. . . Signal input interface

17. . . Power interface

171. . . positive electrode

172. . . negative electrode

18. . . Voltage conversion circuit

181. . . DC/DC converter

19. . . Amplifier

200. . . charger

300. . . Charging circuit

400. . . Battery system

41. . . battery

42. . . Battery management system

The first figure is a schematic structural diagram of a specific embodiment of the charging management system, the charging circuit, and the battery management system of the present invention;

The second figure is a circuit diagram of a specific embodiment of the charging management system of the present invention.

100. . . Charging management system

200. . . charger

300. . . Charging circuit

400. . . Battery system

41. . . battery

42. . . Battery management system

Claims (10)

A charging management system for receiving a signal from a rechargeable battery, and controlling a charging circuit disposed in the charger to charge the charged battery according to the signal, the charging management system comprising: a first signal output interface, And outputting, to the charging circuit, a control signal for characterizing the first charging current; the second signal output interface is configured to output a control signal for characterizing the second charging current to the charging circuit, where the second charging current value is less than the first charging current value; a three-signal output interface for outputting a control signal indicative of a variable third charging current to the charging circuit; and a controller electrically connected to the first, second, and third signal output interfaces, the controller for Controlling the charging management system to operate at least in one of two modes: the first mode, the controller selectively controlling the first signal output interface or the second signal output interface to output a control signal; and the second mode, the controller only controls the third The signal output interface outputs a control signal. The battery management system of claim 1, wherein in the first mode, the controller is further configured to simultaneously control the first signal output interface and the second signal output interface to not output the control signal. The battery management system of claim 1, wherein in the first mode, the controller is further configured to first control the first signal output interface to output a control signal, and then control the second signal output interface to output a control signal. The battery management system according to any one of claims 1 to 3, further comprising: a first switch disposed between the controller and the first signal output interface, and a controller disposed at the controller And a second switch between the second signal output interface; the controller controls the first signal output interface or the second signal output interface output/non-output control by controlling the on/off of the first or second switch Signal. The battery management system of claim 4, wherein the first switch and the second switch each comprise an optical coupling relay. The battery management system of claim 1, wherein in the second mode, the controller is configured to control the third signal output by outputting a Pulse Width Modulation (PWM) signal to the third signal output interface. The output of the interface. The battery management system of claim 1, wherein the charging management system further comprises a signal input interface for receiving a communication signal from the rechargeable battery; the controller is further configured to capture the signal input interface input. And control the output of the first, second, or third signal output interface according to the signal. The battery management system of claim 1, wherein the charge management system further comprises a power interface for receiving power from the battery being charged, and a voltage conversion circuit coupled between the power interface and the controller. The battery management system of claim 8, wherein the positive and negative terminals of the power interface each comprise two conductive terminals. A charger comprising: a charge management system according to any one of the preceding claims; and a charging circuit for receiving a control signal from the charge management system and corresponding to the control signal Output charging current.