A charging and discharging system and energy storage device

Abstract

The application provides a charging and discharging system and an energy storage device, the charging and discharging system comprising at least one battery pack; a bidirectional inverter adapted to forward inverting output AC current and reversely connecting AC commercial power to charge the battery pack; when forward inverting output, the battery pack provides DC current output to the bidirectional inverter, and then inverts output AC current; when reverse AC charging, AC commercial power is input to the bidirectional inverter to rectify and convert output DC current to the battery pack for charging; the forward inverting output power P1 of the bidirectional inverter is greater than the reverse charging power P2 thereof, and the reverse charging power P2 is greater than or equal to the total maximum charging power of the at least one battery pack. In this way, the charging power of each battery pack can be satisfied, the cost is low, and the technical problems in the prior art that the charging power of an adapter is limited and it is difficult to satisfy fast charging of multiple external battery packs or the cost of fast charging sought by a user is high can be effectively solved.

Description

Technical Field

[0001] This invention relates to the field of charging and discharging technology, and more specifically, to a charging and discharging system and an energy storage device. Background Technology

[0002] Currently, portable energy storage power supplies on the market can be roughly divided into two basic types. One type has the battery pack connected in series / parallel inside the energy storage power supply body. The DC output of the battery pack is converted to AC output by an inverter to meet the user's AC needs. Of course, the DC output of the battery pack can also be converted from DC to DC to meet the user's DC needs, such as USB and cigarette lighter. However, the battery pack of this type of energy storage power supply cannot be removed by the user for use with external cordless devices, such as cordless lawnmowers and cordless grass trimmers. Another type involves externally mounted battery packs within a power storage device. These power storage devices allow users to remove the battery packs independently for use with cordless devices. These devices typically come with a separate adapter suitable for external AC power for charging the battery packs. However, the adapter's charging power is limited, making it difficult to quickly charge multiple external battery packs. When users want to quickly charge the battery packs, they must seek adapters with higher charging power. But high-power charging adapters are obviously expensive, resulting in higher costs for users seeking fast charging. Summary of the Invention

[0003] The present invention aims to solve the above-mentioned technical problems and provide a charging and discharging system.

[0004] The present invention provides a charging and discharging system, comprising: At least one battery pack; A parallel management module, which is adapted to manage the charging or discharging of the battery pack and maintains electrical and communication connections with the battery pack; A bidirectional inverter, which is suitable for forward inverter output of AC current and reverse connection of AC mains power to charge the battery pack, and is connected to one end of the parallel management module; During forward inverter output, the battery pack provides DC current to the parallel management module, which then outputs it to the bidirectional inverter, thereby inverting and outputting AC current. During reverse AC charging, the AC mains power input is rectified and converted by the bidirectional inverter to output DC current to the parallel management module, so that the parallel management module manages the output charging current to charge the battery pack; The forward inverter output power P1 of the bidirectional inverter is greater than its reverse charging power P2, and the reverse charging power P2 is greater than or equal to the total maximum charging power of the at least one battery pack.

[0005] Furthermore, during reverse AC charging, the DC current output by the bidirectional inverter rectifies and converts to meet the requirement that the battery pack is charged at a 1C rate.

[0006] Furthermore, the parallel management module is adapted to communicate and identify the battery pack and read the current voltage of the battery pack.

[0007] Furthermore, the parallel management module is adapted to output branch control signals to control the battery packs with higher voltages among the multiple battery packs to discharge preferentially until their voltages drop to match the voltages of the battery packs with lower voltages, at which point the multiple battery packs discharge together, or; The parallel management module is adapted to output branch control signals to control the battery pack with low voltage among the multiple battery packs to discharge preferentially to the low voltage protection, end the discharge, and switch to another branch control signal output to control the discharge of another battery pack.

[0008] Furthermore, the battery pack is adapted to detect the battery pack voltage, and when the battery pack voltage drops to a preset threshold, control the disconnection of the battery pack output; or; When the parallel management module detects that the output voltage of the battery pack has dropped to a certain preset threshold, it controls the disconnection of the output branch between the battery pack and the parallel management module.

[0009] Furthermore, the parallel management module is adapted to output multiple control signals to control multiple battery packs to charge simultaneously, and each branch connected to the battery pack is also equipped with a current regulation unit to limit and regulate the charging current of each branch.

[0010] Furthermore, the bidirectional inverter includes a bidirectional DC / DC unit and a bidirectional AC / DC unit, as well as an AC output port and an AC input port connected to the bidirectional AC / DC unit; During forward inverter output, the battery pack provides DC current to the parallel management module, which outputs it to the bidirectional DC / DC unit for voltage conversion before transmitting it to the bidirectional AC / DC unit for inversion, and outputs AC current through the AC output port. During reverse AC charging, the AC input port is connected to AC mains power. The AC mains power is input to the bidirectional AC / DC unit for rectification and output DC current, which is then transmitted to the bidirectional DC / DC unit for voltage conversion and input to the parallel management module. The parallel management module manages and outputs the charging current to charge the battery pack.

[0011] Furthermore, the bidirectional inverter includes a DC-AC unit connected to the AC output port and an AC-DC unit connected to the AC input port, as well as a bidirectional DC-DC unit connected to the DC-AC unit and the AC-DC unit respectively. During forward inverter output, the battery pack provides DC current to the parallel management module, which then outputs it to the bidirectional DC / DC unit for voltage conversion before transmitting it to the DC-AC unit for inversion, and finally outputs AC current through the AC output port. During reverse AC charging, the AC input port is connected to AC mains power. The AC mains power is input to the AC-DC unit for rectification and output DC current, which is then transmitted to the bidirectional DC / DC unit for voltage conversion and input to the parallel management module. The parallel management module manages and outputs the charging current to charge the battery pack.

[0012] Furthermore, the AC-DC unit is independently external.

[0013] Furthermore, the system also includes a DC output port, which is connected to the parallel management module via a step-down circuit.

[0014] Furthermore, the system also includes a DC output port, which is connected to the bidirectional DC-DC unit via a step-down circuit.

[0015] Furthermore, during forward inverter output, the DC current of the battery pack is managed by the parallel management module and output to the bidirectional DC / DC unit for voltage conversion. Part of the current is then transmitted to the step-down circuit and output as DC current through the DC output port. During reverse AC charging, the AC mains power is rectified by the bidirectional AC / DC unit or the AC-DC unit to output DC current. After voltage conversion by the bidirectional DC / DC unit, part of the current is transmitted to the step-down circuit and output as DC current through the DC output port.

[0016] Furthermore, the system also includes a DC input interface connected to the parallel management module. The DC input interface is adapted to receive DC charging current and transmit it to the parallel management module so that the parallel management module can manage and output the charging current to charge the battery pack.

[0017] Furthermore, the DC input interface is adapted to accept a wide DC voltage input.

[0018] Another charging and discharging system provided by the present invention includes: At least one battery pack; A bidirectional inverter adapted to output AC current in the forward direction and connect to AC mains power in the reverse direction to charge the battery pack, and comprising: A bidirectional DC / DC unit is configured to correspond one-to-one with the output branch of each of the battery packs; a bidirectional AC / DC unit is connected to each of the bidirectional DC / DC units. During forward inverter output, the battery pack provides DC current to the corresponding bidirectional DC / DC unit, which converts the voltage and outputs it to the bidirectional AC / DC unit, thereby inverting and outputting AC current. During reverse AC charging, the AC mains power input is rectified and converted by the bidirectional AC / DC unit to output DC current to each of the bidirectional DC / DC units for voltage conversion, so that the charging current is output through each of the bidirectional DC / DC units to charge the corresponding battery pack. The forward inverter output power P1 of the bidirectional inverter is greater than its reverse charging power P2, and the reverse charging power P2 is greater than or equal to the total maximum charging power of the at least one battery pack.

[0019] Furthermore, during reverse AC charging, the DC current output by the bidirectional AC / DC unit rectifies and converts to meet the requirement that the battery pack is charged at a 1C rate.

[0020] Furthermore, during forward inverter output, each of the bidirectional DC / DC units is adapted to convert the output voltage of the corresponding battery pack to the same voltage for output to the bidirectional AC / DC unit.

[0021] Furthermore, during reverse AC charging, the AC mains power is rectified and converted by the bidirectional AC / DC unit to output a single voltage to each of the bidirectional DC / DC units. Each of the bidirectional DC / DC units converts the voltage and / or charge of the corresponding battery pack according to the identified reading to a charging current suitable for charging each battery pack.

[0022] Furthermore, the system also provides a bypass between the bidirectional DC / DC unit and the bidirectional AC / DC unit, which is connected to a step-down circuit, and the step-down circuit is connected to the DC output port.

[0023] Furthermore, during forward inverter output, the DC current of each battery pack is converted to the same voltage by the corresponding bidirectional DC / DC unit, and then output to the buck circuit and output DC current through the DC output port. During reverse AC charging, the AC mains power is rectified by the bidirectional AC / DC unit to output a single voltage, which is then transmitted to the step-down circuit and output as DC current through the DC output port.

[0024] Furthermore, the system also includes a DC input interface connected to each of the bidirectional DC / DC units. The DC input interface is adapted to receive DC charging current and transmit it to each of the bidirectional DC / DC units so that each of the bidirectional DC / DC units outputs charging current to charge the corresponding battery pack.

[0025] Furthermore, the DC input interface is adapted to accept a wide DC voltage input.

[0026] On the other hand, the present invention also provides an energy storage device, comprising: a mounting housing having an installation space therein; at least one battery pack being detachably disposed in a mounting portion of the mounting housing; the energy storage device further comprising: a charging and discharging system as described in any of the above embodiments, the charging and discharging system being disposed in the installation space; wherein the mounting portion is provided with terminals for electrically connecting the battery pack to the charging and discharging system.

[0027] Compared with the prior art, the beneficial technical effects of the present invention are as follows: This invention enables high-power charging of each battery pack at a low cost, effectively solving the technical problems of limited charging power of adapters in the prior art, which makes it difficult to quickly charge multiple external battery packs or the high cost of fast charging for users. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 : Schematic diagram of the principle of specific embodiment 1 of the present invention; Figure 2 : Schematic diagram of the parallel management module in specific embodiment 1 of the present invention; Figure 3 : Another schematic diagram of the parallel management module in specific embodiment 1 of the present invention; Figure 4 : Principle block diagram of specific embodiment 1 of the present invention; Figure 5 Another principle block diagram of specific embodiment 1 of the present invention; Figure 6 Another schematic diagram of the principle of a specific embodiment 1 of the present invention; Figure 7 Another principle block diagram of specific embodiment 1 of the present invention; Figure 8Another principle block diagram of specific embodiment 1 of the present invention; Figure 9 Another principle block diagram of specific embodiment 1 of the present invention; Figure 10 Another principle block diagram of specific embodiment 1 of the present invention; Figure 11 : Principle block diagram of specific embodiment 2 of the present invention; Figure 12 Another principle block diagram of specific embodiment 2 of the present invention; Figure 13 Another principle block diagram of specific embodiment 3 of the present invention; Figure 14 : Specific implementation of the present invention 1 Solar charging principle block diagram. Detailed Implementation

[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1: Reference Figure 1 As shown, a charging and discharging system 10 includes: At least one external battery pack 100 having battery pack terminals; Parallel management module 200 is suitable for electrical and communication connection with battery pack 100. Parallel management module 200 is used to realize charging and discharging management of battery pack 100. The bidirectional inverter 300 is connected to the parallel management module 200. The bidirectional inverter 300 is equipped with an AC output port and an AC input port. The AC input port is suitable for connecting to an external AC mains power (e.g., 110V or 220V) to charge the battery pack 100.

[0032] Specifically, the charging and discharging system 10 includes a housing, on which a mounting portion adapted to the battery pack 100 is disposed. The mounting portion is disposed with corresponding terminals adapted to be connected to the battery pack terminals. In some specific embodiments, the battery pack terminals include a positive terminal BAT+, a negative terminal BAT-, and a signal terminal D. Correspondingly, the corresponding terminals on the mounting portion also include a positive terminal BAT+, a negative terminal BAT-, and a signal terminal D. In other specific embodiments, the battery pack terminals include a positive terminal BAT+, a negative terminal BAT-, a signal terminal D, and a temperature terminal T. This application does not impose specific limitations on these aspects.

[0033] The corresponding terminals (BAT+, D, BAT-) on the aforementioned mounting section are connected to the aforementioned parallel management module 200. The battery pack 100 is connected to the aforementioned mounting section. Through the matching of the corresponding terminals, the electrical and communication connections between the battery pack 100 and the parallel management module 200 are realized. It should be noted that: The battery pack 100 is preferably connected to the mounting part in a way that allows for easy assembly and disassembly. That is, the battery pack 100 can be mechanically and electrically connected to the mounting part, or it can be unlocked and removed from the mounting part to provide power to the cordless DC tool independently.

[0034] Reference Figure 2 The schematic diagram of the parallel management module shown illustrates that the parallel management module 200 includes a controller (MCU), a processing unit, and an output unit. The processing unit includes multiple processing circuits that manage each battery pack 100. The processing circuits are electrically connected to the controller (MCU), and the battery packs 100 communicate with the parallel management module 200 through signal terminal D. Specifically: When the battery pack 100 is inserted into the mounting part of the charging and discharging system 10, multiple terminals of the battery pack 100 are connected to corresponding terminals on the mounting part. Specifically, an "information code" for identification is sent to the parallel management module 200 through the signal terminal D. The parallel management module 200 judges whether the "information code" meets the preset conditions. If it does, the parallel management module 200 generates a corresponding "model code" in its internal memory based on the "information code" and sends the "model code" back to the battery pack 100. At this time, the battery pack 100 judges that the "model code" is true. Thus, the working status information between the battery pack 100 and the parallel management module 200 is exchanged. Specifically, the working status information exchange includes, for example, the total capacity of the battery pack, the voltage of a single cell in the battery pack, the number of charge and discharge cycles, the initial charge percentage of the battery pack, the battery pack temperature, the battery pack discharge cutoff voltage, and the current voltage information of the battery pack.

[0035] Furthermore, in a specific example, when the operating status information is, for example, the current voltage information of the battery pack, considering the actual usage and the fact that the current voltages of the multiple battery packs 100 connected to the mounting section are not equal, the parallel management module 200 can read and identify that the current voltages of the multiple external battery packs 100 are not equal. Therefore, the controller inside the parallel management module 200 can make corresponding adjustments based on the current voltage of each battery pack 100. For ease of distinction and understanding, the battery pack 100 with the higher current voltage can be defined as the first battery pack, and the battery pack 100 with the lower current voltage can be defined as the second battery pack. The controller can then control the first battery pack to discharge first, causing the second battery pack to disconnect from the first battery pack in parallel. Once the current voltages of the first and second battery packs are essentially the same, the controller can then control the second battery pack to reconnect in parallel with the first battery pack, and control both the first and second battery packs to discharge simultaneously, allowing them to be fully discharged at the same time or facilitating simultaneous charging later.

[0036] Please continue to refer to Figure 2 As shown, the current voltage of battery pack 1 is greater than the current voltage of battery pack 2, and the current voltage of battery pack 2 is greater than the current voltage of battery pack n. The controller (MCU) controls the two MOSFETs on the output branch of battery pack 1 to turn on through processing circuit 1, while processing circuit 2 and processing circuit n control the two MOSFETs on the output branch of the corresponding battery packs to turn off. In this way, only battery pack 1 discharges first. When the current voltage of battery pack 1 drops to the same level as the current voltage of battery pack 2, the controller (MCU) controls the two MOSFETs on the output branch of battery pack 2 to turn on through processing circuit 2, and battery pack 1 and battery pack 2 discharge together in parallel. This process continues until the voltages of the connected battery packs 100 are basically the same, at which point they are connected in parallel to discharge together.

[0037] or; When the parallel management module 200 reads and identifies that the current voltages of the multiple external battery packs 100 are unequal, it controls the MCU to prioritize the discharge of the battery pack 100 with the lower voltage until the lower voltage battery pack 100 discharges to the low-voltage protection level, and then starts the discharge of the battery pack 100 with the higher voltage. It should be noted that the battery pack 100 has built-in BMS protection. When the output voltage of the battery pack 100 drops to a certain preset threshold, the built-in BMS protection controls the disconnection of the battery pack output. Of course, this low-voltage protection can also be set in the parallel management module 200. When the parallel management module 200 reads and identifies (detects) that the output voltage of the battery pack 100 drops to a certain preset threshold, the controller (MCU) controls the disconnection of the output branch between this battery pack 100 and the parallel management module 200, and switches to another output branch for discharge.

[0038] Please continue to refer to Figure 2As shown, the current voltage of battery pack 1 is greater than the current voltage of battery pack 2, and the current voltage of battery pack 2 is greater than the current voltage of battery pack n. The controller (MCU) controls the two MOSFETs on the output branch of battery pack n to turn on through processing circuit n. Processing circuits 1 and 2 control the two MOSFETs on the output branch of the corresponding battery pack to turn off. In this way, only battery pack n discharges until battery pack n discharges to the low voltage protection. Then, the controller (MCU) controls the two MOSFETs on the output branch of battery pack 2 to turn on through processing circuit 2, and battery pack 2 starts discharging. Until battery pack 2 discharges to the low voltage protection, the controller (MCU) controls the two MOSFETs on the output branch of battery pack 1 to turn on through processing circuit 1, and battery pack 1 starts discharging.

[0039] Or perhaps; The parallel management module 200 reads and identifies the battery pack voltage and discharges alternately. The discharge ratio is automatically adjusted according to the current battery pack power until multiple battery packs are discharged simultaneously.

[0040] Furthermore, the parallel management module 200 can also prevent reverse charging between battery packs. As mentioned above, since the voltages of the connected battery packs 100 are not equal, multiple battery packs 100 connected in parallel are prone to reverse charging from a higher-voltage battery pack to a lower-voltage battery pack. Therefore, by setting a reverse MOSFET on the discharge branch of each battery pack 100, reverse charging between battery packs can be effectively avoided. See [link to details] for more information. Figure 2 As shown.

[0041] In addition, it is worth mentioning that: When managing battery pack charging, the parallel management module 200 also addresses the issue of unequal voltages among the connected battery packs 100. When the module detects unequal current voltages of the multiple external battery packs 100, it uses the MCU to prioritize charging the battery pack 100 with the higher voltage until it is fully charged, then adjusts the charging of the other battery pack 100 with the lower voltage. Alternatively, it can prioritize charging the battery pack 100 with the lower voltage until it is fully charged, then adjust the charging of the other battery pack 100 with the higher voltage. Or, it can prioritize charging the battery pack 100 with the lower voltage until it reaches the same voltage as the high-voltage battery pack, then charge them together until they are fully charged. Alternatively, it can control all battery packs 100 to charge simultaneously without prioritizing any charging.

[0042] In addition, the parallel management module 200 can read and identify the battery pack voltage for cross-charging, and the charging ratio can be automatically adjusted according to the current battery pack power until multiple battery packs are fully charged at the same time.

[0043] The parallel management module 200 described above still manages the charging of the battery pack 100 as before. Figure 2 As shown, the controller (MCU) controls the MOSFETs of the corresponding battery pack charging branch (such as the aforementioned output branch) to turn on or off through the corresponding processing circuit, thereby controlling the battery pack charging, as described below. Figure 2 or Figure 3 For example: When the parallel management module 200 reads and identifies that the current voltage of battery pack 1 is greater than the current voltage of battery pack 2, and the current voltage of battery pack 2 is greater than the current voltage of battery pack n, the controller (MCU) controls the two MOSFETs on the charging branch of battery pack 1 to turn on through processing circuit 1, while processing circuit 2 and processing circuit n control the two MOSFETs on the output branch of the corresponding battery pack to turn off. In this way, only battery pack 1 is charged first. When battery pack 1 is fully charged, the controller (MCU) controls the two MOSFETs on the charging branch of battery pack 2 to turn on through processing circuit 2, and battery pack 2 starts charging until battery pack 2 is fully charged. This process continues until all connected battery packs 100 are fully charged.

[0044] or; When the parallel management module 200 reads and identifies that the current voltage of battery pack 1 is greater than the current voltage of battery pack 2, and the current voltage of battery pack 2 is greater than the current voltage of battery pack n, the controller (MCU) controls the two MOSFETs on the charging branch of battery pack n to turn on through the processing circuit n. The processing circuits 1 and 2 control the two MOSFETs on the output branch of the corresponding battery pack to turn off. In this way, only battery pack n is charged. Prioritize charging battery pack n until its voltage is the same as that of battery pack 2. Then, the controller (MCU) controls the two MOSFETs on the charging branch of battery pack 2 to turn on through the processing circuit 2. Battery pack 2 and battery pack n are charged together until their voltages are the same as those of battery pack 1. Then, the controller (MCU) controls the two MOSFETs on the charging branch of battery pack 1 to turn on through the processing circuit 1. Battery packs 1, 2, and n are charged together until fully charged.

[0045] or; like Figure 3 As shown, each battery pack 100 is equipped with a current regulation unit on its corresponding charging branch. The current regulation unit regulates and controls the charging current to ensure that each battery pack 100 is charged simultaneously. In particular, when the total charging power is sufficient, the current regulation unit can be used to regulate the current to charge each battery pack 100 at its maximum charging power. In this way, multiple external battery packs can be quickly charged in a short time.

[0046] Please refer to Figure 1 and Figure 4In the charging and discharging system 10 shown, during AC output discharge (forward inverter output), the DC current input to the multiple battery packs 100 connected in parallel is output to the bidirectional inverter 300 through the output unit of the parallel management module 200, and the inverter outputs AC current to supply the AC output port 30A to output AC current. During AC input charging (reverse AC charging), the external AC mains power (e.g., 110V or 220V) is input to the bidirectional inverter 300 through the AC input port 30B, rectified and output as DC current, and input to the parallel management module 200. The parallel management module 200 manages the charging of the external battery packs. The forward inverter output power P1 of the bidirectional inverter 300 is greater than its reverse charging power P2, and the reverse charging power P2 is greater than or equal to the total maximum charging power of the multiple battery packs 100.

[0047] Specifically, during reverse AC charging, the DC current output by the bidirectional inverter 300 rectifies and converts to meet the charging rate of the battery pack 100 at 1C.

[0048] Please continue to refer to Figure 4 As shown, for ease of explanation, this example uses the charging and discharging system 10 connected to four battery packs 100.

[0049] During AC output discharge, the four battery packs 100 are connected in parallel to their respective mounting parts. The DC current output by the battery packs 100 is input to the parallel management module 200. The parallel management module 200 manages the output DC current with voltage V1 to the bidirectional inverter 300. After inversion, the AC current with voltage V2 is input to the AC output port 30A. At this time, since the four battery packs 100 are connected in parallel, one or more battery packs can be removed for use in other external DC cordless tools. The remaining battery packs 100 connected to their respective mounting parts can still normally meet the AC output discharge requirements.

[0050] When charging via AC input, the AC input port 30B is connected to AC mains power (e.g., 110V or 220V voltage), and the AC current is input to the bidirectional inverter 300. The bidirectional inverter 300 rectifies and outputs a DC current with a voltage of V3, which is then supplied to the external battery pack 100 for charging via the parallel management module 200.

[0051] As mentioned above, the bidirectional inverter 300 has an inverter mode and a charging mode.

[0052] When the charging and discharging system 10 is not connected to the mains power, the bidirectional inverter 300 automatically operates in the inverter state, and the DC current of the battery pack 100 is inverted and output as AC current through the bidirectional AC / DC unit. When the charging and discharging system 10 is connected to the mains power, the bidirectional inverter 300 operates in the charging state, and controls the bidirectional AC / DC unit to rectify the AC current and output as DC current to charge the battery pack.

[0053] In addition, the bidirectional inverter 300 also has a UPS mode. When the charging and discharging system 10 is connected to AC mains for charging and also connected to an AC load, the AC mains directly supplies power to the load through the voltage controller 500, and the excess current is rectified and converted by the bidirectional AC / DC unit to charge the battery pack. At the moment the mains power is disconnected, the system 10 automatically detects the mains power failure and immediately changes the mode to the inverter mode, completing the switch from supplying power to the AC load from the mains power to the inverter power supply in an instant, ensuring that the AC load does not lose power when the mains power is disconnected.

[0054] To be more specific, refer to Figure 1 and Figure 5 As shown, the bidirectional inverter 300 includes a bidirectional DC / DC unit 301 and a bidirectional AC / DC unit 302, as well as a controller (MCU).

[0055] When the charging and discharging system 10 is not connected to the mains power, the bidirectional inverter 300 automatically operates in the inverter state. The DC current of the battery pack 100 is input to the bidirectional DC / DC unit 301 through the output unit DC of the parallel management module 200, and then to the bidirectional AC / DC unit 302, and finally outputs AC current (e.g., 110V or 220V AC). The bidirectional DC / DC unit 301 boosts the parallel output voltage V1 of the parallel management module 200 to V2', and then the bidirectional AC / DC unit 302 inverts the DC voltage V2' to output AC voltage V2. When the charging and discharging system 10 is connected to the mains power, the controller (MCU) of the bidirectional inverter 300 automatically recognizes the mains power and immediately controls the current flow of the bidirectional AC / DC unit 302 and the bidirectional DC / DC unit 301, so that the system 10 operates in the charging state. The bidirectional AC / DC unit 302 rectifies the input AC mains power into a stable DC voltage of V3', and then the bidirectional DC / DC unit 301 converts the stable DC voltage of V3' into a charging current of V3 suitable for charging the battery pack.

[0056] By utilizing the bidirectional inverter 300, the AC output of the charging and discharging system 10 can be guaranteed, and the input of the total charging power can be effectively met. This ensures that each external battery pack can be charged at its maximum charging power. Furthermore, it is less expensive than the traditional method of using an external power adapter for charging. A specific example will be provided below: Assuming the battery pack specifications are as follows: Voltage 20V, capacity 5Ah, maximum continuous discharge current 20A, maximum charging current 8A; The charging and discharging system 10 includes four battery packs 100 connected in parallel with each other; therefore, The forward inverter output power P1 of the bidirectional inverter 300 supports 4×20V×20A=1600W; The maximum charging power of the battery pack is 4×20V×8A=640W; the fastest charging time for a single battery pack is 5 / 8h (37.5min). Thus, the forward inverter output power P1 of the bidirectional inverter 300 of the system 10 can reach 1600W. According to theoretical calculation (considering power loss), the reverse charging power P2 will reach 1600W×80%=1280W>640W. Since the reverse charging power P2 is greater than the maximum charging power, it can meet the input of the total charging power, so as to ensure that each external battery pack can be charged at the maximum charging power.

[0057] In terms of cost, if an external power adapter with a maximum charging power of 640W is required to achieve high-power fast charging, a separate AC-DC rectifier module is required. In addition, the system 10 needs to support 1600W inverter output and also needs to be configured with a DC-DC unit and a DC-AC inverter unit, resulting in a high overall cost. Conversely, by adopting the bidirectional inverter 300, some components used in the charging and inverter output processes can be shared through the application of bidirectional AC / DC and bidirectional DC / DC, which can effectively reduce the overall cost and meet the requirements of high-power charging.

[0058] In other specific embodiments, the bidirectional AC / DC unit 302 in the bidirectional inverter 300 can also be divided into a separate DC-AC unit 302 and an AC-DC unit (charging conversion), as detailed in the following references. Figure 6 and Figure 7 The bidirectional inverter 300' shown is shown. One end of the DC-AC unit 302' is connected to the AC output port 30A, and the other end is connected to the bidirectional DC / DC unit 301. During the inverter output process, the DC current of the battery pack 100 is input to the bidirectional DC / DC unit 301 through the output unit DC of the parallel management module 200, and then to the DC-AC unit 302', and finally outputs AC current (e.g., 110V or 220V AC). The bidirectional DC / DC unit 301 boosts the parallel output voltage V1 of the parallel management module 200 to V2', and then the DC-AC unit 302' inverts the DC voltage of V2' to output AC voltage of V2. During the charging process, the AC mains power is rectified by the AC-DC unit 303 to output a stable DC current with a voltage of V3', which is then input to the bidirectional DC / DC unit 301 through the input port 30B'. The bidirectional DC / DC unit 301 then converts the stable DC current with a voltage of V3' into a charging current with a voltage of V3 suitable for charging the battery pack.

[0059] In particular, the aforementioned AC-DC unit 303 can also be externally mounted to form a form similar to an external power adapter.

[0060] In addition, the aforementioned bidirectional inverter (300, 300') also includes PFC (Power Factor Correction) to improve the power factor.

[0061] Please continue to refer to Figure 6 As shown, the PFC and AC-DC unit (charging conversion) are combined together to form a PFC AC to DC circuit. Furthermore, the PFC AC to DC circuit is independently externalized to form a power adapter similar to an external power adapter.

[0062] In addition, it is worth mentioning that: The charging and discharging system 10 also includes a DC output port 40.

[0063] In some specific embodiments, the DC output port 40 is connected to the parallel management module 200 via a step-down circuit 400, as detailed in the following reference. Figure 1 , Figure 4 and Figure 5 As shown, the DC current of the battery pack 100 is output as DC voltage V1 by the parallel management module 200, and then output as DC voltage V4 by the step-down circuit 400, which is used for output by the DC output port 40. The DC output port 40 is preferably one or more of the following: USB interface, Type-C interface, and cigarette lighter.

[0064] Reference Figure 8 As shown, in some other specific embodiments, the DC output port 40 is connected to the bidirectional inverter 300 via a step-down circuit 400, more specifically referring to... Figure 9 and Figure 10 As shown, the DC output port 40 is connected to the bidirectional DC / DC unit 301 via the step-down circuit 400.

[0065] When the charging and discharging system 10 is connected to AC mains for charging, the controller (MCU) of the bidirectional inverter 300 automatically identifies the AC mains power and immediately controls the current flow of the bidirectional AC / DC unit 302 and the bidirectional DC / DC unit 301, so that the system 10 operates in the charging state. The bidirectional AC / DC unit 302 rectifies the input AC mains power into a stable DC voltage of V3', and then the bidirectional DC / DC unit 301 converts the stable DC voltage of V3' into a charging current of V3 suitable for charging the battery pack. At the same time, the DC current of V3 is output to the step-down circuit 400, and then the step-down circuit 400 outputs DC power of V4 for use by the DC output port 40. The DC output port 40 is preferably one or more of the following: USB interface, Type-C interface, and cigarette lighter. In this way, the battery pack 100 can be effectively prevented from discharging during the charging process, thereby reducing the number of charge and discharge cycles of the battery pack 100 and extending the battery pack's service life.

[0066] When the charging and discharging system 10 is not connected to mains power, the bidirectional inverter 300 automatically operates in inverter mode. The DC current of the battery pack 100 is input to the bidirectional DC / DC unit 301 through the output unit DC of the parallel management module 200, and then to the bidirectional AC / DC unit 302, finally outputting AC current (e.g., 110V or 220V AC). The bidirectional DC / DC unit 301 boosts the parallel output voltage V1 of the parallel management module 200 to V2', and then the bidirectional AC / DC unit 302 inverts the DC voltage V2' to output AC voltage V2. At the same time, the bidirectional DC / DC unit 301 outputs DC current to the step-down circuit 400, and then the step-down circuit 400 outputs DC voltage V4 to be used by the DC output port 40. The DC output port 40 is preferably one or more of the following: USB interface, Type-C interface, and cigarette lighter.

[0067] Example 2: This embodiment is basically similar in structure and principle to the above embodiment 1, except that the parallel management module 200 in the above embodiment 1 is cancelled, and a bidirectional DC / DC unit 301a is configured one by one on the output branch corresponding to each battery pack 100.

[0068] Specifically, please refer to Figure 11As shown, the charging and discharging system 10 includes at least one external battery pack 100. Each battery pack 100 has a bidirectional DC / DC unit 301a configured on its corresponding output branch. Each bidirectional DC / DC unit 301a is connected to a bidirectional AC / DC unit 302a. The bidirectional AC / DC unit 302a is connected to an AC output port 30A and an AC input port 30B. The forward inverter output power P1 of the bidirectional inverter 300 is greater than its reverse charging power P2. The reverse charging power P2 is greater than or equal to the total maximum charging power of the multiple battery packs 100.

[0069] Specifically, during reverse AC charging, the DC current output by the bidirectional inverter 300 rectifies and converts to meet the charging rate of the battery pack 100 at 1C.

[0070] When the charging and discharging system 10 is not connected to the mains power, the system 10 automatically operates in the inverter state. The DC current of each battery pack 100 is transformed to a stable and identical voltage V1 by the bidirectional DC / DC unit 301a, and then to the bidirectional AC / DC unit 302a, finally outputting an AC current (e.g., 110V or 220V AC) with a voltage of V2, which is then output for use through the AC output port 30A.

[0071] In some specific embodiments, each bidirectional DC / DC unit 301a boosts each output voltage (Va, Vb, Vc, Vd) of the multiple parallel battery packs 100 to the same voltage V1.

[0072] Similarly, since the voltages of the connected battery packs 100 are not equal (e.g., Va≠Vb≠Vc≠Vd), the parallel connection of multiple battery packs 100 can easily lead to reverse charging of the battery pack with a higher voltage to the battery pack with a lower voltage. Therefore, a bidirectional DC / DC unit 301a is configured on the output branch corresponding to each battery pack 100. The DC current of each battery pack 100 is transformed to a stable and identical voltage V1 by the corresponding bidirectional DC / DC unit 301a, which can effectively prevent reverse charging between battery packs. At this time, there is no need to manage the discharge sequence of multiple battery packs 100.

[0073] When the charging and discharging system 10 is connected to the mains power, the controller (MCU) of the bidirectional inverter 300 automatically recognizes the mains power and immediately controls the current flow of the bidirectional AC / DC unit 302a and the bidirectional DC / DC unit 301a, so that the system 10 operates in the charging state. The bidirectional AC / DC unit 302a rectifies the AC mains power input through the AC input port 30B into a stable DC voltage of V3', and then each bidirectional DC / DC unit 301a converts the stable DC voltage of V3' into a charging current suitable for charging the corresponding battery pack 100, so as to charge the battery pack 100.

[0074] Similarly, by using bidirectional AC / DC and bidirectional DC / DC converters, the AC output of the charging and discharging system 10 can be guaranteed on the one hand, and the input of the total charging power can be effectively met on the other hand, so as to ensure that each external battery pack can be charged at the maximum charging power. Moreover, it is less expensive than the traditional method of using an external power adapter for charging. For specific examples, see below: Assuming the battery pack specifications are as follows: Voltage 20V, capacity 5Ah, maximum continuous discharge current 20A, maximum charging current 8A; The charging and discharging system 10 includes four battery packs 100 connected in parallel with each other; therefore, The forward inverter output power P1 of the bidirectional AC / DC unit 302a supports 4×20V×20A=1600W; The maximum charging power of the battery pack is 4×20V×8A=640W; the fastest charging time for a single battery pack is 5 / 8h (37.5min). Thus, the forward inverter output power P1 of the bidirectional AC / DC unit 302a of the system 10 can reach 1600W. According to theoretical calculation (considering power loss), the reverse charging power P2 will reach 1600W×80%=1280W>640W. Since the reverse charging power P2 is greater than the maximum charging power, it can meet the input of the total charging power, so as to ensure that each external battery pack can be charged at the maximum charging power.

[0075] Similarly, in terms of cost, if an external power adapter with a maximum charging power of 640W is required to achieve high-power fast charging, a separate AC-DC rectifier module is required. In addition, the system 10 needs to support 1600W inverter output and also needs to be configured with a DC-DC unit and a DC-AC inverter unit, resulting in a higher overall cost. Conversely, by adopting bidirectional AC / DC and bidirectional DC / DC, some components used in the charging and inverter output processes can be shared, which can also effectively reduce the overall cost and meet the requirements of high-power charging.

[0076] Similarly, it is also worth mentioning that: The charging and discharging system 10 also includes a DC output port 40.

[0077] In some specific embodiments, a bypass is provided between the bidirectional DC / DC unit 301a and the bidirectional AC / DC unit 302a, which is connected to the step-down circuit 400. The step-down circuit 400 is connected to the DC output port 40. For details, please refer to [reference needed]. Figure 11 As shown.

[0078] Reference Figure 12 As shown, the charging and discharging system 10 has no mains power connection and is in inverter output mode. The DC current of the battery pack 100 is transformed to a stable and identical voltage V1 by each corresponding bidirectional DC / DC unit 301a. Part of it passes through the bidirectional AC / DC unit 302a, and the inverter output voltage is AC current (e.g., 110V or 220V AC) at V2, which is then output through the AC output port 30A for use by AC loads. The other part passes through the step-down circuit 400 to output DC current at V4, which is then used for output through the DC output port 40. The DC output port 40 is preferably one or more of the following: USB interface, Type-C interface, and cigarette lighter.

[0079] Reference Figure 13 As shown, the charging and discharging system 10 is connected to AC mains power. When the system 10 is in a charging state, the bidirectional AC / DC unit 302a rectifies the input AC mains power into a stable DC voltage of V3'. Part of this stable DC voltage of V3' is then converted into a charging current of V3' suitable for charging the battery pack by the bidirectional DC / DC unit 301. The other part outputs a DC current of V3' to the step-down circuit 400. Then, the step-down circuit 400 outputs a DC voltage of V4 for use by the DC output port 40. The DC output port 40 is preferably one or more of the following: USB interface, Type-C interface, and cigarette lighter. In this way, the battery pack 100 can be effectively prevented from discharging during the charging process, thereby reducing the number of charge and discharge cycles of the battery pack 100 and extending the battery pack's lifespan.

[0080] In addition, the charging and discharging system 10 also has a UPS mode. When the charging and discharging system 10 is connected to AC mains for charging and also connected to an AC load, the AC mains directly supplies power to the load through the voltage controller 500, and the excess current is rectified and converted by the bidirectional AC / DC unit to charge the battery pack. At the moment the mains power is disconnected, the system 10 automatically detects the mains power failure and immediately changes the mode to the inverter mode, instantly completing the switch from supplying power to the AC load from the mains power to the inverter, ensuring that the AC load does not lose power when the mains power is disconnected.

[0081] In addition, it is worth mentioning that: The charging and discharging systems 10 provided in Embodiments 1 and 2 above are also equipped with DC charging function, that is, charging the battery pack 100 through a DC input interface; the specific illustration is given in Embodiment 1, please refer to the diagram for details. Figure 14As shown, the charging and discharging system 10 is equipped with a DC input interface 50 suitable for receiving DC input current. The DC input interface 50 is connected to the parallel management module 200, which manages the charging of the external battery pack 100. In this way, the parallel management module 200 can realize a wide DC voltage input, such as 20V-120V. In particular, when the DC input power is greater than or equal to the total maximum charging power of multiple battery packs 100, the parallel management module 200 can ensure that each external battery pack can be charged at the maximum charging power, and can also meet the requirement of charging the battery pack 100 at a 1C rate.

[0082] In particular, please continue to refer to Figure 14 As shown, the DC input mentioned above comes from the solar charger. Specifically, during solar charging, the solar charger connects to the DC input interface 50 through the MPPT controller and inputs a DC charging current with a voltage of Vs to the parallel management module 200. The parallel management module 200 manages the charging of the battery pack 100 according to the current voltage of the identified external battery pack 100.

[0083] In the above embodiment 2, the DC input interface 50 is connected to each bidirectional DC / DC unit 301a. Each bidirectional DC / DC unit 301a converts the stable DC voltage of Vs (the charging current input by the DC input interface 50 is Vs) into a charging current suitable for charging the corresponding battery pack 100, so as to charge the battery pack 100. Similarly, a wide DC voltage input can also be realized. When the DC input power is greater than or equal to the total maximum charging power of multiple battery packs 100, each bidirectional DC / DC unit 301a can enable the corresponding external battery pack to be charged at the maximum charging power, which also satisfies the requirement that the battery pack 100 is charged at a 1C rate.

[0084] In a particularly preferred embodiment, the DC input to the device also comes from a solar charger.

[0085] Example 3 The present invention also provides an energy storage device. Specifically, the energy storage device includes, for example, a mounting housing with an installation space inside, and at least one battery pack is detachably disposed in the mounting portion of the mounting housing.

[0086] Furthermore, the energy storage device may include, for example, the charging and discharging system described in Embodiment 1 above or the charging and discharging system described in Embodiment 2 above.

[0087] When the energy storage device includes the charging and discharging system as described in Embodiment 1 above, the charging and discharging system is housed within the installation space. The installation portion is provided with terminals for electrically connecting the battery pack to the charging and discharging system. Correspondingly, this embodiment can achieve the technical effects corresponding to any of the technical solutions in Embodiment 1 above, which will not be elaborated further here. When the energy storage device includes the charging and discharging system as described in Embodiment 2 above, the charging and discharging system is housed within the installation space. The installation portion is provided with terminals for electrically connecting the battery pack to the charging and discharging system. Correspondingly, this embodiment can achieve the technical effects corresponding to any of the technical solutions in Embodiment 2 above, which will not be elaborated further here. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A charging and discharging system, characterized in that, include: At least one battery pack; A bidirectional inverter adapted to output AC current in the forward direction and connect to AC mains power in the reverse direction to charge the battery pack, and comprising: A bidirectional DC / DC unit is configured to correspond one-to-one with the output branch of each of the battery packs; a bidirectional AC / DC unit is connected to each of the bidirectional DC / DC units. During forward inverter output, the battery pack provides DC current to the corresponding bidirectional DC / DC unit, which converts the voltage and outputs it to the bidirectional AC / DC unit, thereby inverting and outputting AC current. During reverse AC charging, the AC mains power input is rectified and converted by the bidirectional AC / DC unit to output DC current to each of the bidirectional DC / DC units for voltage conversion, so that the charging current is output through each of the bidirectional DC / DC units to charge the corresponding battery pack. The forward inverter output power P1 of the bidirectional inverter is greater than its reverse charging power P2, and the reverse charging power P2 is greater than or equal to the total maximum charging power of the at least one battery pack. The charging and discharging system includes a parallel management module, which is suitable for electrical and communication connection with the battery pack. The parallel management module is used to realize the charging and discharging management of the battery pack. The parallel management module reads and identifies the battery pack voltage and discharges alternately. The discharge ratio is automatically adjusted according to the current battery pack power until multiple battery packs are discharged simultaneously. The parallel management module reads and identifies the battery pack voltage and performs cross-charging. The charging ratio is automatically adjusted according to the current battery pack power until multiple battery packs are fully charged at the same time.

2. The charging and discharging system according to claim 1, characterized in that: During reverse AC charging, the DC current output by the bidirectional AC / DC unit rectifies and converts to meet the requirement that the battery pack is charged at a 1C rate.

3. The charging and discharging system according to claim 1, characterized in that: During forward inverter output, each of the bidirectional DC / DC units is adapted to convert the output voltage of the corresponding battery pack to the same voltage for output to the bidirectional AC / DC unit.

4. The charging and discharging system according to claim 1, characterized in that: During reverse AC charging, the AC mains power is rectified and converted by the bidirectional AC / DC unit to output a single voltage to each of the bidirectional DC / DC units. Each of the bidirectional DC / DC units converts the voltage and / or charge of the corresponding battery pack according to the identified reading to a charging current suitable for charging each battery pack.

5. The charging and discharging system according to claim 1, characterized in that: The system also includes a bypass between the bidirectional DC / DC unit and the bidirectional AC / DC unit, which is connected to a step-down circuit, and the step-down circuit is connected to the DC output port.

6. The charging and discharging system according to claim 5, characterized in that: During forward inverter output, the DC current of each battery pack is converted to the same voltage by the corresponding bidirectional DC / DC unit, and then output to the step-down circuit and output DC current through the DC output port. During reverse AC charging, the AC mains power is rectified by the bidirectional AC / DC unit to output a single voltage, which is then transmitted to the step-down circuit and output as DC current through the DC output port.

7. The charging and discharging system according to claim 1, characterized in that, The system also includes a DC input interface connected to each of the bidirectional DC / DC units. The DC input interface is adapted to receive DC charging current and transmit it to each of the bidirectional DC / DC units so that the charging current is output through each of the bidirectional DC / DC units to charge the corresponding battery pack.

8. The charging and discharging system according to claim 7, characterized in that: The DC input interface is suitable for connecting DC wide voltage input.

9. An energy storage device, characterized in that, include: The mounting housing has an internal mounting space. The at least one battery pack is detachably disposed on the mounting portion of the mounting housing; the energy storage device further includes: The charging and discharging system according to any one of claims 1-8, wherein the charging and discharging system is disposed within the mounting space; wherein the mounting portion is provided with terminals for electrically connecting the battery pack to the charging and discharging system.

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