Parallel charging system and parallel charging method

Abstract

A parallel charging method sequentially includes: acquiring storage voltages of a plurality of battery devices by a main battery device according to a communication means; controlling the battery device with the lowest storage voltage in the plurality of battery devices to be conducted with a power supply device so as to be charged by the power supply device; and when the voltage difference between the storage voltage of the other battery devices in the plurality of battery devices and the output voltage of the power supply device is smaller than a preset voltage, connecting the other battery devices with the power supply device, so that the other battery devices are quickly and safely charged by the power supply device.

Description

Technical Field

[0001] The present disclosure relates to a charging technology, and more particularly to a parallel charging system and a parallel charging method. Background Art

[0002] In the application of battery modules, if some batteries are abnormal and the charging and discharging is stopped, there will be voltage inequality in the battery module, which may cause errors and damage in charging and discharging. Therefore, a technology that can balance cost and charging and discharging stability is needed. Summary of the invention

[0003] The present disclosure relates to a parallel charging method, which includes: obtaining the storage voltages of multiple battery devices through a main battery device according to a communication method; controlling the battery device with the lowest storage voltage among the multiple battery devices to be connected to a power supply device so as to be charged by the power supply device; and when the voltage difference between the storage voltage of other battery devices among the multiple battery devices and the output voltage of the power supply device is less than a preset voltage, connecting the other battery devices to the power supply device so that the other battery devices are charged by the power supply device.

[0004] In one embodiment, each of the battery devices includes a charging switch and a discharging switch, and the parallel charging method further includes: when each of the battery devices is connected to the power supply device, turning on the charging switch and turning off the discharging switch to enter a waiting charging mode; and after each of the battery devices senses a charging current, turning on the discharging switch to enter a charging mode.

[0005] In one embodiment, the parallel charging method further includes: before the master battery device determines the battery device with the lowest storage voltage among the plurality of battery devices, turning off all the charging switches and the discharging switches in the plurality of battery devices.

[0006] In one embodiment, the step of connecting the other battery devices to the power supply device so that the other battery devices are charged by the power supply device includes: the other battery devices sequentially enter the charging mode; and when the storage voltage of each of the other battery devices is charged to the full charge voltage, each of the other battery devices stops being charged by the power supply device.

[0007] In one embodiment, the step of turning on the discharge switch to enter the charging mode further includes: determining the size of the charging current when each of the battery devices senses the charging current; and turning on the discharge switch to enter the charging mode when the charging current is greater than a current threshold.

[0008] The present disclosure also relates to a parallel charging system, comprising a main battery device and a plurality of battery devices. The plurality of battery devices are communicatively connected to the main battery device. The plurality of battery devices are connected in parallel to each other and coupled to a power supply device. The main battery device is used to obtain the storage voltage of the plurality of battery devices, and to select the battery device with the lowest storage voltage among the plurality of battery devices to be charged by the power supply device. The other battery devices among the plurality of battery devices are used to monitor the output voltage of the power supply device. When the output voltage rises and the voltage difference between the output voltage and the storage voltage of the other battery devices is less than a preset voltage, the other battery devices are charged by the power supply device.

[0009] In one embodiment, each of the battery devices comprises an energy storage element, a charging switch and a discharging switch. The charging switch is coupled to the energy storage element. The discharging switch is connected in series with the charging switch. The discharging switch and the charging switch are coupled between the energy storage element and the power supply device.

[0010] In one embodiment, each of the battery devices further comprises a controller. The controller is coupled to the discharge switch and the charge switch. When the output voltage rises to the storage voltage of each of the battery devices, the controller is used to turn on the charge switch and turn off the discharge switch to enter a waiting charging mode. After the controller senses the charging current, the discharge switch is turned on to enter a charging mode.

[0011] In one embodiment, before the main battery device selects the battery device with the lowest storage voltage to be charged by the power supply device, the controller turns off the charging switch and the discharging switch in each of the battery devices.

[0012] In one embodiment, the controller is further configured to detect the charging current, so as to turn on the discharge switch when the charging current is greater than a current threshold.

[0013] In one embodiment, the discharge switch of each of the battery devices comprises a one-way switch, and the one-way switch of the discharge switch is used to allow the charging current to pass through.

[0014] In one embodiment, the charging switch of each of the battery devices comprises a unidirectional switch, and a conducting direction of the unidirectional switch of the charging switch is opposite to a conducting direction of the unidirectional switch of the discharging switch.

[0015] Accordingly, through communication between multiple parallel battery devices and by monitoring the output voltage of the power supply device, each battery device will be able to start charging from the battery with the lowest power and enter the charging mode in sequence according to the change in output voltage to complete charging quickly and safely. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of a parallel charging system according to some embodiments of the present disclosure.

[0017] Figure 2 is a flow chart of a parallel charging method according to some embodiments of the present disclosure.

[0018] Figure 3 Schematic diagram of a battery device according to some embodiments of the present disclosure.

[0019] Figure 4 A flowchart for charging a battery device according to some embodiments of the present disclosure.

[0020] Figure 5 Schematic diagram of a battery device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0021] The following will disclose multiple embodiments of the present invention with the accompanying drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is, in some embodiments of the present invention, these practical details are not necessary. In addition, in order to simplify the drawings, some conventional structures and elements will be depicted in a simple schematic manner in the drawings.

[0022] In this document, when an element is referred to as "connected" or "coupled", it may refer to "electrically connected" or "electrically coupled". "Connected" or "coupled" may also be used to indicate that two or more elements cooperate or interact with each other. In addition, although the terms "first", "second", etc. are used in this document to describe different elements, the terms are only used to distinguish between elements or operations described by the same technical terms. Unless the context clearly indicates otherwise, the terms do not specifically refer to or imply an order or sequence, nor are they used to limit the present invention.

[0023] Figure 1 FIG. 1 is a schematic diagram of a parallel charging system 100 according to some embodiments of the present disclosure. The parallel charging system 100 includes a plurality of battery devices 200A-200I. The battery devices 200A-200I are connected via connecting wires (eg Figure 1 The connecting lines L1 and L2 are coupled to the power supply device PD and the load device LD. The battery devices 200A-200I are used to form a battery module to be charged by the power supply device PD and output power to the load device LD when necessary (eg, when the power supply of the power supply device is unstable).

[0024] Each battery device 200A-200I is connected in parallel, but can be connected to the connection lines L1 and L2 by selectively controlling the internal switch to charge or discharge. In addition, each battery device 200A-200I is provided with a communication circuit for transmitting information. The internal structure of each battery device 200A-200I will be described in detail in the following paragraphs.

[0025] In one embodiment, one main battery device is set among the multiple battery devices 200A-200I, and the battery device 200A is used as the "main battery device" for the purpose of explanation. The main battery device 200A can be set in advance by the operator of the parallel charging system 100, or can be determined by the multiple battery devices 200A-200I according to the program setting (e.g., the one with the highest storage power is the main battery, or the one with the highest battery health is the main battery), but the present disclosure is not limited to this.

[0026] The battery devices 200B-200I are communicatively connected to the main battery device 200A (e.g., through a communication circuit) so that the main battery device 200A can obtain the storage voltage (i.e., storage power) of each of the battery devices 200B-200I. The main battery device 200A will select the battery device with the "lowest storage voltage" among the battery devices 200B-200I, and control this battery device to be charged by the power supply device PD first. For example: among the battery devices 200B-200I, the storage voltage of the battery device 200B is 20 volts, which means that the storage power is 20%, and the storage voltages of the other battery devices 200C-200I are all greater than 20 volts, then the main battery device 200A will control the battery device 200B to be connected to the power supply device PD for priority charging.

[0027] In one embodiment, the power supply device PD charges the battery device 200B in a constant current charge (CC) manner. In addition, during the charging process, the voltage on the connection line L1 (i.e., the output voltage of the power supply device PD) changes dynamically with the charging process, for example, as the storage voltage of the battery device 200B gradually increases.

[0028] Since the battery devices 200A-200I are connected in parallel, when the power supply device PD charges the battery device 200B, the remaining battery devices 200A, 200C-200I will be able to monitor the output voltage of the power supply device PD (e.g., detecting the voltage of the connection line L1 and / or L2). When each battery device 200A, 200C-200I determines that the output voltage is close to its own storage voltage, each battery device 200A, 200C-200I will control the internal switch to conduct to the connection line L1 / L2 to be charged by the power supply device PD.

[0029] Specifically, the storage voltage of the battery device 200B is 20 volts, so the output voltage of the power supply device PD is also 20 volts, and will gradually increase during the charging process. When the output voltage gradually increases, the other battery devices 200A, 200C~200I will determine whether the output voltage is close to their own energy storage voltage (that is, the voltage difference between the storage voltage and the output voltage is effective to the preset voltage). For example, the storage voltage of the battery device 200C is 30 volts. When the output voltage rises to 30 volts, the battery device 200C will automatically conduct to the supply connection line L1. In this way, each battery device 200A~200I can be charged by the power supply device PD in sequence (that is, according to the size of the storage voltage).

[0030] The present disclosure utilizes communication and monitoring of output voltage to instantly determine whether each battery device can be charged. Since the battery device will only be connected to the connection line and the power supply device PD when the output voltage is close to the storage voltage, the safety of the entire system can be improved to avoid voltage cross-injection problems between different battery devices due to abnormal operation. In addition, through the parallel structure design of the battery device, the system will not need to set up a dedicated charging processor to reduce system costs.

[0031] Figure 2 The figure shows a schematic diagram of a parallel charging method according to some embodiments of the present disclosure. In step S201, the main battery device 200A first obtains the storage voltage of the battery devices 200B-200I through a communication means. The "communication means" can be a wired connection between multiple battery devices 200A-200I (e.g., connected via a data line L3), or a wireless connection established by multiple battery devices 200A-200I through an internal communication circuit or a wireless transmission module. Since people in the field can understand the method of establishing data transmission between battery devices 200A-200I, it will not be further described here.

[0032] In step S202, the main battery device 200A determines the battery device with the lowest storage voltage. In one embodiment, the determination target of the main battery device 200A includes itself. In other words, the main battery device 200A determines the low-power battery in all battery devices 200A-200I. Here, the battery device 200B with the lowest storage voltage (e.g., 20 volts) is used as an example for description.

[0033] In step S203, after confirming the battery device 200B with the lowest power, the master battery device 200A controls the battery device 200B to be connected to the power supply device PD so as to be powered by the power supply device PD. In one embodiment, each battery device 200A-200I has at least one switch element. When the switch element is turned on, the corresponding battery device can be connected to the power supply device PD through the connection line L1. The internal structure of the battery devices 200A-200I will be described in detail in the following paragraphs.

[0034] In step S204, the battery devices 200A, 200C to 200I except the battery device 200B each monitor the output voltage of the power supply device PD. Figure 1 In the embodiment shown, it is assumed that the connection line L2 is a ground terminal, so the output voltage can be confirmed by detecting the voltage of the connection line L1. In S205, the other battery devices 200A, 200C-200I determine whether the voltage difference between the output voltage and their respective storage voltages is less than a preset voltage.

[0035] If the voltage difference between the output voltage and the respective storage voltage is smaller than the preset voltage, then in step S206 , the corresponding battery device will be connected to the power supply device PD so that the corresponding battery device is charged by the power supply device PD.

[0036] Figure 3 FIG. 3 is a schematic diagram of a battery device 300 according to some embodiments of the present disclosure. The battery device 300 may be applied to Figure 1 Any of the battery devices 200A-200I shown. In one embodiment, the battery device 300 receives power provided by the power supply device PD through the positive connection interface P+ and the connection line L1, and outputs power to the load device LD through the negative connection interface P-connection line L2, but the present disclosure is not limited to this. In other embodiments, the battery device 300 can also be selectively charged or discharged at different times / situations through a single connection line L1.

[0037] The battery device 300 includes an energy storage element 310, a charging switch W1, and a discharging switch W2. The energy storage element 310 may be a battery module composed of one or more battery cells for storing electrical energy.

[0038] The charging switch W1 and the discharging switch W2 are connected in series and coupled between the energy storage element 310 and the connection line L1 (power supply device PD). In one embodiment, the control ends of the charging switch W1 and the discharging switch W2 receive control signals S1 and S2, respectively, to be controlled in an on or off state. For example, the charging switch W1 and the discharging switch W2 may be metal oxide semiconductor field effect transistors, and each has a unidirectional switch D1 and D2 (e.g., a parasitic diode). The conduction direction of the unidirectional switch D1 of the charging switch W1 is opposite to the conduction direction of the unidirectional switch D2 of the discharging switch W2.

[0039] As mentioned above, when the charging switch W1 and the discharging switch W2 are not turned on according to the control signals S1 and S2, the current can still pass through the unidirectional switches D1 and D2 respectively through the charging switch W1 and the discharging switch W2. Figure 3 As shown, the conduction direction of the unidirectional switch D1 in the charging switch W1 is “from the energy storage element 310 to the connection line L1 (discharging)”. In other words, the control signal S1 is used to control the charging switch W1 to conduct in the direction “from the connection line L1 to the energy storage element 310 (charging)”.

[0040] Similarly, the conduction direction of the unidirectional switch D2 in the discharge switch W2 is “from the connection line L1 to the energy storage element 310 (charging)”. In other words, the control signal S2 is used to control the discharge switch W2 to conduct in the direction “from the energy storage element 310 to the connection line L1 (discharging)”.

[0041] In one embodiment, the battery device 300 further includes a controller 320 and a transmission interface 330. The controller 320 is coupled to the charging switch W1 and the discharging switch W2 to generate or transmit control signals S1 and S2 to the charging switch W1 and the discharging switch W2.

[0042] The transmission interface 330 is coupled to the controller 320 and the data line L3 . Figure 1 The controller of the battery devices 200B-200I shown can send the current storage voltage via the transmission interface 330 and the data line L3; Figure 1 The controller of the main battery device 200A receives the storage voltage from other battery devices 200B-200I via the transmission interface 330 and the data line L3. In one embodiment, the transmission interface 330 may be a bus of CAN (controller area network) communication specification, but the present disclosure is not limited thereto.

[0043] See also Figure 3As shown, in one embodiment, when the battery device 300 is not to be charged or discharged (e.g., before the main battery device 200A determines the battery device with the lowest storage), the controller 320 will control the charging switch W1 and the discharging switch W2 to be turned off. When the battery device 300 is to be charged by the power supply device PD, the charging switch W1 will be controlled to be turned on, and the discharging switch W2 will be controlled to be turned off. The aforementioned "being charged by the power supply device PD" situation can be executed when notified by the main battery device 200A or when the battery device 300 determines that the output voltage on the connection line L1 is close to its own storage voltage.

[0044] When the charging switch W1 is turned on and the discharging switch W2 is turned off, the battery device 300 is in the "waiting charging mode". At this time, although the discharging switch W2 is not turned on, the charging current provided by the power supply device PD can still pass through the unidirectional switch D2. When the controller 320 senses the charging current, it turns on the discharging switch W2 to put the battery device 300 into the "charging mode".

[0045] In some embodiments, the controller 320 determines the magnitude of the charging current flowing through the unidirectional switch D2 of the discharge switch W2 , and turns on the discharge switch W2 only when the charging current is greater than a preset current threshold.

[0046] Figure 4 The flowchart of the charging method according to some embodiments of the present disclosure is shown, which can be applied to Figure 2 In step S401, when the battery device 300 is about to be connected to the power supply device PD, the controller 320 turns on the charging switch W1 and maintains the discharging switch W2 to be turned off, so that the battery device 300 enters the waiting charging mode. As mentioned above, the situation of "the battery device 300 is connected to the power supply device PD" can be "the main battery device 200A controls the battery device 200B with the lowest storage voltage to be charged" or "the battery device 200C monitors to determine whether the output voltage is close to its own storage voltage".

[0047] When the battery device 300 is in the waiting charging mode, the charging current provided by the power supply device PD will sequentially pass through the unidirectional switch D2 in the discharge switch W2 and the turned-on charging switch W1 to form a charging loop.

[0048] In step S402, when the controller 320 detects the charging current, the controller 320 turns on the discharge switch W2 to put the battery device 300 into the charging mode. In one embodiment, the controller 320 determines the magnitude of the charging current, and turns on the discharge switch W2 when the charging current is greater than the current threshold.

[0049] It is particularly important to mention that, although in the aforementioned embodiment, the battery device 300 first passes through the waiting charging mode and then enters the charging mode through a plurality of switches W1 and W2, the present disclosure is not limited thereto, and in some embodiments, the battery device 300 may also only have a single switch element, and when the output voltage is close to its own storage voltage, the switch element is turned on to directly enter the charging mode.

[0050] Please refer to Figure 1 and Figure 3 As shown, since the power supply device PD will dynamically adjust the output voltage according to the current charging situation, the battery devices 200A~200I can confirm the current output voltage of the power supply device PD by monitoring the voltage of the connection lines L1 and / or L2. For example: the cross-voltage between the connection lines L1 and L2 can be regarded as the output voltage, or if one of the connection lines L1 / L2 is the ground terminal, only the voltage of the other needs to be detected. When the voltage difference between the output voltage and its own storage voltage is less than the preset voltage, the battery device 200A~200I automatically turns on the energy storage element 310 to the power supply device PD. Accordingly, each battery device 200A~200I can enter the waiting charging mode and the charging mode in sequence (according to the size of their respective storage voltages) as the output voltage gradually increases.

[0051] Furthermore, in one embodiment, when the storage voltage of each battery device 200A-200I is charged to a full charge voltage (e.g., 100 volts, or 90% of the maximum storage capacity), the controller 320 of each battery device 200A-200I turns off the charging switch W1 and the discharging switch W2 to stop charging the powered device PD.

[0052] See also Figure 3 As shown, in some embodiments, the battery device 300 further includes a fuse element F1, F2 (eg, a fuse, an overvoltage switch) and an impedance element R1 coupled to the positive connection interface P+ or the negative connection interface P−.

[0053] Figure 5 FIG. 5 is a schematic diagram of a battery device 500 according to some embodiments of the present disclosure. The battery device 500 can also be applied to Figure 1 Any of the battery devices 200A to 200I shown. Figure 5 In, with Figure 3 Similar elements related to the embodiments of the present invention are denoted by the same reference numerals for easy understanding, and the specific principles of similar elements have been described in detail in the previous paragraphs. Figure 5 The components have a cooperative operation relationship and need to be introduced, which will not be repeated here.

[0054] The battery device 500 also includes an energy storage element 310, a controller 320, a transmission interface 330, a charging switch W1, and a discharging switch W2. In an application of an embodiment, the connection line L1 is connected to the ground terminal (or low voltage), and the connection line L2 is used to receive a high voltage. Therefore, the charging switch W1 and the discharging switch W2 are set on the line corresponding to the negative connection interface P-, and are connected in series with the impedance element R1 and the fuse element F2. The charging switch W1 and the discharging switch W2 can receive control signals S1 and S2 from the controller 320 to Figure 2 The parallel charging method shown is turned on sequentially so that the corresponding battery devices are charged by the power supply device PD.

[0055] according to Figure 2 In the parallel charging method shown, each battery device 200A-200I can be charged by the power supply device PD in sequence, and the connection with the power supply device PD is cut off when the storage voltage reaches the full charge voltage. Accordingly, the parallel charging system 100 can efficiently and safely charge multiple battery devices 200A-200I without complicated and high installation costs.

[0056] The various elements, method steps or technical features in the aforementioned embodiments may be combined with each other and are not limited to the order of textual description or the order of presentation of the drawings in the present disclosure.

[0057] Although the present disclosure has been disclosed as above in the form of implementation methods, it is not intended to limit the present disclosure. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the attached claims.

[0058]

Explanation of symbols

[0059] 100: Parallel charging system

[0060] 200A-200I:Battery Device

[0061] 310: Energy storage element

[0062] 320: Controller

[0063] 330: Transmission interface

[0064] PD: Power Supply Device

[0065] LD: Load Device

[0066] L1: Connection line

[0067] L2: Connection line

[0068] L3: Data line

[0069] W1: Charging switch

[0070] W2: discharge switch

[0071] D1: One-way switch

[0072] D2: One-way switch

[0073] S1: control signal

[0074] S2: Control signal

[0075] P+: Positive connection interface

[0076] P-: Negative connection interface

[0077] F1: Insurance element

[0078] F2: Insurance element

[0079] R1: Impedance element

[0080] S201-S206: Steps

[0081] S401-S402: steps.

Claims

1. A parallel charging method, characterized in that: In order: Obtaining storage voltages of a plurality of battery devices through a master battery device according to a communication means; Controlling the battery device with the lowest storage voltage among the plurality of battery devices to be connected to the power supply device so as to be charged by the power supply device; as well as When the voltage difference between the storage voltage of other battery devices among the multiple battery devices and the output voltage of the power supply device is less than a preset voltage, the connection between the other battery devices and the power supply device is turned on so that the other battery devices are charged by the power supply device.

2. The parallel charging method according to claim 1, characterized in that: Each of the battery devices comprises a charging switch and a discharging switch, and the parallel charging method further comprises: When each of the battery devices is connected to the power supply device, the charging switch is turned on and the discharging switch is turned off to enter a waiting charging mode; as well as After each of the battery devices senses the charging current, the discharge switch is turned on to enter a charging mode.

3. The parallel charging method according to claim 2, characterized in that: Also includes: Before the master battery device determines the battery device with the lowest storage voltage among the plurality of battery devices, all the charging switches and the discharging switches in the plurality of battery devices are turned off.

4. The parallel charging method according to claim 2, characterized in that: The step of connecting the other battery device to the power supply device so that the other battery device is charged by the power supply device comprises: The other battery devices sequentially enter the charging mode; as well as When the storage voltage of each of the other battery devices is charged to the full-charge voltage, each of the other battery devices stops being charged by the power supply device.

5. The parallel charging method according to claim 2, characterized in that: The step of turning on the discharge switch to enter the charging mode further includes: When each of the battery devices senses the charging current, determining the magnitude of the charging current; and When the charging current is greater than a current threshold, the discharge switch is turned on to enter the charging mode.

6. A parallel charging system, characterized in that: Include: Main battery unit; as well as A plurality of battery devices, communicatively connected to the main battery device, wherein the plurality of battery devices are connected in parallel to each other and coupled to a power supply device; wherein the main battery device is used to obtain the storage voltages of the plurality of battery devices, and to select the battery device with the lowest storage voltage among the plurality of battery devices to be charged by the power supply device; as well as The other battery devices among the plurality of battery devices are used to monitor the output voltage of the power supply device. When the output voltage rises and the voltage difference between the output voltage and the storage voltage of the other battery devices is less than a preset voltage, the other battery devices are charged by the power supply device.

7. The parallel charging system according to claim 6, characterized in that: Each of the battery devices comprises: Energy storage components; a charging switch coupled to the energy storage element; and A discharge switch is connected in series with the charge switch, wherein the discharge switch and the charge switch are coupled between the energy storage element and the power supply device.

8. The parallel charging system according to claim 7, characterized in that: Each of the battery devices further comprises: A controller coupled to the discharge switch and the charge switch, wherein when the output voltage rises to the storage voltage of each of the battery devices, the controller is used to turn on the charge switch and turn off the discharge switch to enter a waiting charging mode; as well as After the controller senses the charging current, the discharge switch is turned on to enter the charging mode.

9. The parallel charging system according to claim 8, characterized in that: Before the main battery device selects the battery device with the lowest storage voltage to be charged by the power supply device, the controller turns off the charging switch and the discharging switch in each of the battery devices.

10. The parallel charging system according to claim 8, characterized in that: The controller is further configured to detect the charging current, so as to turn on the discharge switch when the charging current is greater than a current threshold.

11. The parallel charging system according to claim 7, characterized in that: The discharge switch of each of the battery devices includes a one-way switch, and the one-way switch of the discharge switch is used to allow the charging current to pass through.

12. The parallel charging system according to claim 11, characterized in that: The charging switch of each of the battery devices includes a unidirectional switch, and the conducting direction of the unidirectional switch of the charging switch is opposite to the conducting direction of the unidirectional switch of the discharging switch.

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