Battery pack and protection method thereof

Abstract

The invention provides a battery pack and a protection method thereof. A battery comprises a battery cell assembly, a control module, a charging and discharging interface and a switch module, and the switch module comprises a first switch module and a second switch module; the first protection module comprises a first parameter acquisition module; the control module can control on and off of at least the first switch module according to the electrical parameters; the second protection module comprises a second parameter acquisition module; the control module can control on and off of at least the second switch module according to the electrical parameters; the node position of the electrical parameter detected by the second protection module is different from the node position of the electrical parameter detected by the first protection module, and / or the position of the first switch module is different from the position of the second switch module. By arranging multiple acquisition modules and / or switches at different positions, the risk of circuit protection failure can be reduced, and the safety and reliability of the battery pack are improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of battery packs, and in particular to a battery pack and a protection method thereof. Background Art

[0002] As a portable and reusable energy source, battery packs have been widely used in power tools, household appliances and other fields.

[0003] Among them, lithium-ion battery packs are the most common, with good energy density and cycle life. Lithium-ion battery packs have high requirements for battery charging and discharging conditions. A charging and discharging process that does not meet the requirements will affect the life of the battery pack and even pose a safety hazard. Therefore, people will set up a protection circuit in the battery pack to monitor the charging and discharging parameters of the battery pack. When the charging and discharging parameters of the battery pack exceed the preset conditions, the switch will be actively disconnected for protection.

[0004] Existing protection circuits usually use a single detection circuit to detect the charge and discharge parameters of the battery pack, and disconnect the charge and discharge circuit by controlling a single switch. When the detection circuit or switch fails or is delayed, the battery pack cannot be effectively protected, and the safety and reliability are poor. Summary of the invention

[0005] In view of this, an object of the present disclosure is to provide a battery pack with good safety and reliability.

[0006] Based on the above objectives, the present disclosure provides a battery pack, the battery pack comprising:

[0007] A battery cell assembly, a control module, a charge and discharge interface, a switch module connected in series between the battery cell assembly and the charge and discharge interface, the switch module comprising a first switch module and a second switch module; and,

[0008] The first protection module includes a first parameter acquisition module electrically connected to the battery cell assembly and the control module; the first parameter acquisition module detects the electrical parameters of the battery cell assembly, and the control module can control the on and off of at least the first switch module according to the electrical parameters;

[0009] The second protection module includes a second parameter acquisition module electrically connected to the battery cell assembly and the control module; the second parameter acquisition module detects the electrical parameters of the battery cell assembly, and the control module can control the on and off of at least the second switch module according to the electrical parameters;

[0010] The node position at which the second protection module detects the electrical parameter is different from the node position at which the first protection module detects the electrical parameter, and / or the position of the first switch module is different from the position of the second switch module.

[0011] In one embodiment, the first parameter acquisition module includes a cell sampling chip, which is electrically connected between the control module and the cell assembly and is used to collect electrical parameters of the cell assembly.

[0012] In one embodiment, the charge and discharge interface includes an electric tool interface, the first switch module includes a charge and discharge switch, the charge and discharge switch is connected in series between the battery cell assembly and the electric tool interface, and is electrically connected to the control module; when the electrical parameters of the battery cell assembly collected by the first parameter acquisition module exceed a preset threshold, the control module can control at least the charge and discharge switch to be disconnected.

[0013] In one embodiment, the charging and discharging interface includes a universal serial bus interface, and the second parameter acquisition module includes a voltage regulation module, which is electrically connected between the universal serial bus interface and the battery cell assembly and is used to collect electrical parameters of the battery cell assembly.

[0014] In one embodiment, the second switch module includes a power switch of the universal serial bus interface and a loop switch of the voltage regulation module, and the power switch of the universal serial bus interface and the loop switch of the voltage regulation module are connected in series between the battery cell assembly and the universal serial bus interface;

[0015] When the electrical parameters of the battery cell assembly collected by the second parameter collection module exceed a preset threshold, the control module can control at least one of the second switch modules to be disconnected.

[0016] In one embodiment, the second switch module further includes a battery protection switch tube and / or a fuse, and the battery protection switch tube and / or the fuse are connected in series between the battery cell assembly and the universal serial bus interface.

[0017] In one embodiment, the voltage regulating module is also used to adjust the voltage of the battery cell assembly to match the voltage for powering the universal serial bus interface, or to adjust the voltage of the universal serial bus interface to match the voltage for powering the battery cell assembly according to the control signal of the control module.

[0018] In one embodiment, the electrical parameters sampled by the cell sampling chip or the voltage regulating module include at least a single cell voltage and a whole pack voltage.

[0019] In one embodiment, the battery pack further includes a secondary cell protection chip, which is electrically connected between the control module and the cell assembly and is used to collect electrical parameters of the cell assembly;

[0020] The cell secondary protection chip sets a secondary protection preset threshold, where the secondary protection preset threshold is higher than the preset threshold of the electrical parameters of the first parameter acquisition module and / or the second parameter acquisition module;

[0021] When the electrical parameter of the battery cell assembly exceeds a preset threshold value of the secondary protection, the control module can selectively control at least one switch in the switch module to be disconnected.

[0022] Based on the same inventive concept, the present disclosure also provides a battery pack protection method, the battery pack includes a battery cell assembly, a control module, a charge and discharge interface, a switch module connected in series between the battery cell assembly and the charge and discharge interface, the switch module includes a first switch module and a second switch module; and a first protection module and a second protection module, the first protection module includes a first parameter acquisition module, the second protection module includes a second parameter acquisition module, the method includes:

[0023] Detecting electrical parameters of the battery cell assembly through the first parameter acquisition module;

[0024] Detecting the electrical parameters of the battery cell assembly through the second parameter acquisition module;

[0025] Controlling the on and off of at least the first switch module according to the electrical parameters of the battery cell assembly collected by the first parameter collection module;

[0026] Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly collected by the second parameter collection module;

[0027] The node position at which the second protection module detects the electrical parameter is different from the node position at which the first protection module detects the electrical parameter, and / or the position of the first switch module is different from the position of the second switch module.

[0028] In one of the embodiments, the first parameter acquisition module includes a cell sampling chip;

[0029] The electrical parameters of the battery cell assembly are detected by the first parameter acquisition module, including:

[0030] The electrical parameters of the battery cell assembly are detected by a battery cell sampling chip, and the battery cell sampling chip is electrically connected between the control module and the battery cell assembly.

[0031] In one embodiment, the charge and discharge interface includes a power tool interface, the first switch module includes a charge and discharge switch, the charge and discharge switch is connected in series between the battery cell assembly and the power tool interface, and is electrically connected to the control module;

[0032] According to the electrical parameters of the battery cell assembly collected by the first parameter collection module, at least the first switch module is controlled to be turned on and off, including: when the electrical parameters of the battery cell assembly collected by the first parameter collection module exceed a preset threshold, at least the charge and discharge switch can be controlled to be turned off.

[0033] In one embodiment, the charge and discharge interface includes a universal serial bus interface, and the second parameter acquisition module includes a voltage regulation module;

[0034] The electrical parameters of the battery cell assembly are detected through the second parameter acquisition module, including:

[0035] The electrical parameters of the battery cell assembly are collected through the voltage regulation module, and the voltage regulation module is electrically connected between the universal serial bus interface and the battery cell assembly.

[0036] In one embodiment, the second switch module includes a power switch of the universal serial bus interface and a loop switch of the voltage regulation module, and the power switch of the universal serial bus interface and the loop switch of the voltage regulation module are connected in series between the battery cell assembly and the universal serial bus interface;

[0037] Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly collected by the second parameter collection module includes: when the electrical parameters of the battery cell assembly collected by the second parameter collection module exceed a preset value, being able to control at least one of the second switch modules to be disconnected.

[0038] In one embodiment, the second switch module further includes a battery protection switch tube and / or a fuse.

[0039] Compared with the prior art, the technical solution provided by the present invention forms multiple acquisition modules and multiple loop switches by setting a first parameter acquisition module, a second parameter acquisition module and / or switch modules at multiple different positions. Even if one of the acquisition circuits and / or one of the switches fails, the circuit fault can still be accurately judged through other acquisition modules and / or switches, and the circuit protection function can be achieved, thereby improving the accuracy and safety and reliability of battery pack voltage detection and reducing the risk of battery pack circuit protection failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the present disclosure or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 A schematic diagram of a battery pack provided in an embodiment of the present disclosure;

[0042] Figure 2 A flowchart of a battery pack protection method provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0044] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0045] In the prior art, in order to ensure the safety of the battery pack and the user, a detection circuit, a control circuit and a switch are set inside the battery pack. When the detection circuit detects that the battery pack is abnormal, the control circuit disconnects the switch for protection. When the battery pack has only one level of protection, such as when the detection circuit and / or the switch fails, it may be impossible to obtain accurate parameters of the battery pack and perform protection.

[0046] Some battery packs adopt a dual protection mechanism for the circuit. Taking voltage as an example, first, by setting up a single-chip microcomputer and a parameter sampling circuit, the voltage value is obtained by detecting the connection point of a single battery cell to the ground or to a certain potential point, forming a single overvoltage protection. Then a dedicated chip protection group is set up, and the voltage value is obtained again by detecting the connection point of a single battery cell to the ground or to a certain potential point, forming a double overvoltage protection. The collection results of the single-chip microcomputer and the parameter sampling circuit and the collection results of the dedicated chip protection group are input into the processor. The processor sets a circuit-breaking action threshold. When the voltage value received by the processor is higher than the circuit-breaking action threshold, it is determined that an overvoltage fault has occurred, and the charge and discharge switch is controlled to disconnect the battery pack circuit, thereby forming a dual protection structure for the battery pack, in which the circuit-breaking action threshold of the double overvoltage protection is higher than that of the single overvoltage protection. The disadvantage is that both protections obtain voltage values ​​by detecting the connection point of a single battery cell to the ground or to a certain potential point, and both use charge and discharge switches to realize circuit on and off. Therefore, if there is an abnormality in the internal circuit components of the battery pack or the circuit connection is abnormal, the collected voltage values ​​of the double protections will be inaccurate, and it will be impossible to accurately predict whether an overvoltage fault will occur, that is, the overvoltage protection is still prone to failure; or if the charge and discharge switch fails, both protections cannot normally disconnect the circuit, which will also cause invalid circuit protection.

[0047] Based on this, the present disclosure provides a battery pack that can detect electrical parameters at different node positions through different protection modules, and make judgments and controls, thereby reducing the risk of protection failure caused by a fault at a certain location, such as Figure 1 As shown, an embodiment of a battery pack of the present disclosure is shown, and the battery pack can be selectively connected to a charger for charging. The charger is, for example, a lithium-ion battery charger for portable electronic devices, a lithium-ion battery protection circuit charger, etc. The battery pack includes: a battery cell assembly 100, a control module 200, a charge and discharge interface, a switch module connected in series between the battery cell assembly 100 and the charge and discharge interface, and a first protection module and a second protection module. The switch module includes a first switch module and a second switch module.

[0048] The battery cell assembly 100 is used to provide power, such as a battery pack or a single battery in series, parallel or hybrid combination. The charging and discharging interface is used to charge and discharge the battery cell assembly 100, including a universal serial bus interface 300 (such as a USB-type interface) and a power tool interface 700. One end of the universal serial bus interface 300 is connected to a charger or an electrical appliance, and the other end is connected to the battery cell assembly 100 through a switch module and a control module 200. Preferably, the universal serial bus interface 300 is a Type-C interface.

[0049] The first protection module includes a first parameter acquisition module. The first parameter acquisition module is electrically connected to the battery cell assembly 100 and the control module 200, and is used to directly detect the electrical parameters of the battery cell assembly 100 at the battery cell assembly 100. The electrical parameters include single-cell voltage parameters and whole-package voltage parameters, temperature parameters, power parameters, current parameters, and power parameters of the battery cell assembly 100. The first parameter acquisition module includes a special application integrated circuit. The special application integrated circuit adopts a battery cell sampling chip 400. The battery cell sampling chip 400 is capable of collecting electrical parameters of a single cell and a whole package of the battery cell assembly 100. The battery cell sampling chip 400 transmits the collected electrical parameters of a single cell and a whole package of the battery cell assembly 100 to the control module 200 by means of data communication. Preferably, the battery cell sampling chip 400 transmits the collected electrical parameters of a single cell and a whole package of the battery cell assembly 100 to the control module 200 by means of a two-wire serial bus (IIC) communication. Optionally, other conventional communication methods such as a serial peripheral interface (SPI) and a universal asynchronous receiver / transmitter (UART) can also be used.

[0050] The second protection module includes a second parameter acquisition module electrically connected to the battery cell assembly 100 and the control module 200. The second parameter acquisition module is used to detect the electrical parameters of the battery cell assembly 100. The electrical parameters include single-cell voltage parameters and whole-package voltage parameters, temperature parameters, power parameters, current parameters, power parameters, etc. The second parameter acquisition module includes a voltage regulation module 502, which is electrically connected to the universal serial bus interface 300 and establishes an electrical connection with the battery cell assembly 100 through a part of the hardware circuit, and can collect the electrical parameters of a single cell and a whole package of the battery cell assembly 100 at the voltage regulation module 502. The voltage regulation module 502 is also used to adjust the voltage of the battery cell assembly 100 to match the voltage supplied to the universal serial bus interface 300, or to adjust the voltage of the universal serial bus interface 300 to match the voltage supplied to the battery cell assembly 100 according to the control signal of the control module 200. Specifically, the voltage regulation module 502 is a step-down or step-up chopper (Buck-boost loop). The step-down or step-up chopper is communicatively connected to the control module 200 .

[0051] The first switch module includes a charge and discharge switch 601 connected in series between the battery cell assembly 100 and the power tool interface 700, and electrically connected to the control module 200. The control module 200 presets a first threshold value, compares the electrical parameter collected by the battery cell sampling chip 400 with the first threshold value, and when the electrical parameter collected by the battery cell sampling chip 400 exceeds the first threshold value, the control module 200 controls the charge and discharge switch 601 to be disconnected to achieve the first level of circuit protection. It can be understood that the first threshold value is set corresponding to the electrical parameter. For example, the electrical parameter is a single cell voltage, and the preset first threshold value is a single cell overcharge voltage first threshold value. When the control module 200 determines that the collected single cell voltage exceeds the single cell overcharge voltage first threshold value, it is determined that the battery pack has an overcharge risk, so the charge and discharge switch 601 is controlled to be disconnected to disconnect the electrical circuit between the charger connected to the power tool interface 700 or the universal serial bus interface 300 and the battery cell assembly 100, thereby achieving the first level of overcharge protection.

[0052] The second switch module includes a power switch 604 of the universal serial bus interface and a loop switch 605 (Buck-boost switch tube) of the voltage regulation module. The power switch 604 of the universal serial bus interface and the loop switch 605 of the voltage regulation module are connected in series between the battery cell assembly 100 and the universal serial bus interface 300. The control module 200 presets a second threshold value, and the second threshold value is also set corresponding to the electrical parameter. When the electrical parameter collected by the voltage regulation module 502 exceeds the second threshold value, the control module 200 controls the disconnection of the switch in any second switch module to achieve the second circuit protection. Both circuit protections are software layer protections, which are regarded as double protections of primary circuit protection. Of course, the switches in multiple second switch modules can also be disconnected as needed to improve stability. Taking the electrical parameter of a single cell voltage as an example again, the preset second threshold is the second threshold of the single cell overcharge voltage. When the control module 200 determines that the collected single cell voltage exceeds the second threshold of the single cell overcharge voltage, it is determined that the battery pack is at risk of overcharging, and thus controls to disconnect either one of the power switch 604 of the universal serial bus interface and the loop switch 605 of the voltage regulation module, or both, to disconnect the electrical circuit between the charger connected to the power tool interface 700 or the universal serial bus interface 300 and the battery cell assembly 100, thereby achieving the second level of overcharge protection. Circuit protection generally includes but is not limited to overcharge protection, undervoltage protection, overcurrent protection, overtemperature protection, low temperature protection, component failure protection, etc. Here, the second threshold can be equal to the first threshold, or it can be higher than the first threshold, without specific limitation.

[0053] Generally speaking, in order to realize the charging and discharging function of the universal serial bus interface 300, it must be equipped with a voltage regulating module 502. The present disclosure uses the voltage regulating module 502 provided by the universal serial bus interface 300 to realize voltage detection, omitting the secondary protection chip 501 of the battery cell, and there is no need to set up a voltage detection circuit separately, which is lower in cost. At the same time, the loop switch 605 of the voltage regulating module provided by the voltage regulating module 502 is used as one of the switches of the second overcharge or over-discharge protection, which saves circuit cost and improves the stability of overcharge or over-discharge protection without adding switches.

[0054] Furthermore, when the electrical parameter collected by the voltage regulation module 502 exceeds the second threshold, the control module 200 may also choose to control the charge and discharge switch 601 to be disconnected.

[0055] Preferably, the first threshold is equal to the second threshold, and the control module 200 can implement the circuit protection function according to any loop of the first protection module or the second protection module. Optionally, the first threshold is set to be greater than the second threshold, or the first threshold is set to be less than the second threshold as needed. It can be understood that the detection node positions of the electrical parameters of the first protection module and the second protection module are not the same, so that even if one of the protection modules fails or is delayed, it does not affect the other protection module, and thus the circuit protection function can be implemented by the other protection module, thereby improving the stability of the circuit protection. In addition, the positions of the switch modules of the double protection modules are set to multiple and independent loops, which do not interfere with each other. Even if one of the switches fails, the circuit can be disconnected by other switches, thereby improving the stability of the circuit protection.

[0056] In one embodiment, the second switch module further includes a battery protection switch tube 602 and a fuse 603 connected in series between the battery cell assembly 100 and the universal serial bus interface 300. The fuse 603 is used for current overload protection. When the current passing through the fuse 603 exceeds the fuse current threshold of the fuse 603, the fuse 603 is blown and the battery pack circuit is disconnected, thereby playing a role in the joint protection of voltage and current.

[0057] Optionally, the second switch module also includes a three-terminal fuse. The three-terminal fuse can be blown when the voltage reaches the second threshold or the current reaches the fuse current threshold, and at the same time plays the role of secondary overvoltage protection and overcurrent protection. Optionally, the switch module can select and set other conventional switches that are connected in series between the battery cell assembly 100 and the power tool interface 700 and are electrically connected to the control module 200 as needed, and are uniformly controlled to be disconnected by the control module 200, which will not be elaborated here.

[0058] In one embodiment, the battery pack also includes a secondary cell protection chip 501. The secondary cell protection chip 501 is electrically connected between the control module 200 and the cell assembly 100, and is used to collect electrical parameters of the cell assembly, specifically, to collect single-cell voltage parameters of the cell assembly 100. The secondary cell protection chip 501 presets a secondary protection preset threshold, and directly compares the collected voltage parameter with the secondary voltage protection preset threshold. The secondary voltage protection preset threshold is higher than the first voltage threshold and the second voltage threshold. When the first protection module and the second protection module fail or delay, and when the single-cell voltage parameter of the cell assembly 100 exceeds the secondary voltage protection preset threshold, the secondary cell protection chip 501 controls any one or more switches in the switch module to disconnect, thereby realizing the third level of overcharge protection. Preferably, the secondary cell protection chip 501 controls the disconnection of the battery protection switch tube 602 or the charge and discharge switch 601. The secondary cell protection chip 501 can form a hardware protection layer for overcharge protection, which can be regarded as secondary overcharge protection and complement the software protection layer for primary overcharge protection, forming a multi-level protection mechanism combining software and hardware, further improving the stability of overcharge protection.

[0059] Alternatively, the cell secondary protection chip 501 transmits the collected electrical parameters to the control module 200. When the first protection module and the second protection module fail or are delayed, and when the electrical parameters of the cell assembly 100 exceed the preset threshold of the secondary protection, the control module 200 controls any one or more switches in the switch module to disconnect, thereby realizing the third level of circuit protection.

[0060] The electrical parameters of a single cell and the entire pack of the battery cell assembly 100 are collected through the battery cell sampling chip 400 and the voltage regulation module 502 to form the first and second circuit protection. The electrical parameters of the battery cell assembly 100 are collected through the battery cell secondary protection chip 501 to form the third circuit protection. A plurality of switch modules are then set at different positions. Even if one of the acquisition circuits and / or one of the switches fails, the circuit fault can still be accurately determined through other acquisition modules and / or switch modules, and the circuit protection function can be achieved, thereby improving the accuracy and reliability of the battery pack voltage detection and reducing the risk of battery pack circuit protection failure.

[0061] It can be understood that the specific working principle of this embodiment is as follows: the control module 200 obtains the electrical parameters of the battery cell assembly 100 collected by the battery cell sampling chip 400 and the voltage regulation module 502 through communication, and the battery cell secondary protection chip 501 collects the electrical parameters of the battery cell assembly 100. When the electrical parameters of the battery cell assembly 100 exceed the first threshold, the control module 200 controls to disconnect at least one switch in the first switch module. When the electrical parameters of the battery cell assembly 100 exceed the second threshold, the control module 200 controls to disconnect at least one switch in the second switch module.

[0062] If the first parameter acquisition module fails or is delayed, or the cell secondary protection chip 501 detects that the electrical parameter of the cell assembly 100 exceeds the secondary protection preset threshold, the cell secondary protection chip 501 or the control module 200 controls to disconnect at least one switch in the switch module.

[0063] In one embodiment, the control module 200 includes an integrated chip of a main microcontroller unit (main MCU) and a control unit (PD) of a universal serial bus interface. In this case, the control module 200 can operate and control the entire battery pack, which is convenient to use. Optionally, the control module 200 can also be composed of two chips independently set by the main MCU and the PD as needed, that is, the main MCU and the PD operate independently, but the main MCU and the PD are electrically connected and communicate with each other. At this time, the main MCU controls the charge and discharge switch 601, and the PD controls the power switch 604 of the universal serial bus interface and the loop switch 605 of the voltage regulation module. The battery protection switch tube 602 and the fuse 603, the user or manufacturer can choose to control either the main MCU or the PD as needed. For example: the PD obtains the electrical parameters of the Type-C interface part and communicates these parameters to the main MCU, and the main MCU can directly execute the disconnection of any one or more switches in the switch module to achieve circuit protection. It is also possible that the main MCU collects the electrical parameters and passes them to the PD, and then the PD controls the disconnection of any one or more switches in the switch module to achieve circuit protection. Likewise, the main MCU may also disconnect any one or more switches in the switch module based on the data transmitted by the PD.

[0064] In one embodiment, the battery pack is connected to the electrical appliance or charger through the power tool interface 700, wherein the battery pack includes at least an analog signal terminal (CS) and a digital signal terminal (DA). The electrical appliance is the application end of the battery pack, such as a power tool; the charger is a charging device having a power tool interface that matches the battery pack. The universal serial bus interface 300 is connected to the control module 200 in electrical communication, and can receive the electrical parameters of the battery cell assembly 100 acquired by the control module 200. Preferably, the control module 200 simultaneously transmits the electrical parameters of the current battery cell assembly 100, or the control signal generated by the control module 200 to the electrical appliance or charger through the analog signal terminal (CS) and the digital signal terminal (DA), thereby realizing double insurance of signal transmission. Among them, the analog signal terminal serves as the first signal protection, and the digital signal terminal serves as the second signal protection. When the battery pack fails, the control module 200 transmits the fault signal to the electrical appliance or charger, that is, the control module 200 simultaneously transmits the fault signal to the electrical appliance or charger through the analog signal terminal and the digital signal terminal. When the electrical appliance or charger receives any fault signal transmitted from the analog signal terminal and the digital signal terminal, it controls to disconnect its own circuit, thereby realizing the safety protection function of the electrical appliance or charger.

[0065] Furthermore, the charger or the electrical appliance is also provided with a delayed disconnection module, and the charger or the electrical appliance is connected to the control module 200 for mutual communication. The delayed disconnection module is used to automatically determine that the communication has timed out and control the disconnection of the circuit of the charger or the electrical appliance when the charger or the electrical appliance does not receive the communication feedback signal of the control module 200 after a set time. In addition, the charger or the electrical appliance determines and controls whether the circuit with the battery pack needs to be disconnected with delay through communication feedback, so that when the control module 200 fails, that is, when the control module 200 can no longer feedback the communication signal, the battery pack circuit of the battery pack is disconnected by using the delayed disconnection module of the charger or the electrical appliance, so as to further protect the battery pack with external equipment and improve the safety of the battery pack.

[0066] The present disclosure also provides a battery pack protection method, such as Figure 2 As shown, the battery pack includes a battery cell assembly 100, a control module 200, a charge and discharge interface, a switch module connected in series between the battery cell assembly 100 and the charge and discharge interface, the switch module includes a first switch module and a second switch module; and a first protection module and a second protection module, the first protection module includes a first parameter acquisition module, and the second protection module includes a second parameter acquisition module, and the method includes:

[0067] Detecting electrical parameters of the battery cell assembly 100 through the first parameter acquisition module;

[0068] Detecting electrical parameters of the battery cell assembly 100 through the second parameter acquisition module;

[0069] Controlling the on and off of at least the first switch module according to the electrical parameters of the battery cell assembly 100 collected by the first parameter collection module;

[0070] Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly 100 collected by the second parameter collection module;

[0071] The node position at which the second protection module detects the electrical parameter is different from the node position at which the first protection module detects the electrical parameter, and / or the position of the first switch module is different from the position of the second switch module.

[0072] In one embodiment, the first parameter acquisition module includes a cell sampling chip 400;

[0073] The electrical parameters of the battery cell assembly 100 are detected by the first parameter acquisition module, including:

[0074] The electrical parameters of the cell assembly 100 are detected by the cell sampling chip 400 , and the cell sampling chip 400 is electrically connected between the control module 200 and the cell assembly 100 .

[0075] In one embodiment, the charge and discharge interface includes a power tool interface 700 , and the first switch module includes a charge and discharge switch 601 . The charge and discharge switch 601 is connected in series between the battery cell assembly 100 and the power tool interface 700 , and is electrically connected to the control module 200 .

[0076] According to the electrical parameters of the battery cell assembly 100 collected by the first parameter collection module, at least the first switch module is controlled to be turned on and off, including: when the electrical parameters of the battery cell assembly 100 collected by the first parameter collection module exceed a preset threshold, the charge and discharge switch 601 can be controlled to be turned off.

[0077] In one embodiment, the charge and discharge interface includes a universal serial bus interface 300 , and the second parameter acquisition module includes a voltage regulation module 502 .

[0078] The electrical parameters of the battery cell assembly 100 are detected by the second parameter acquisition module, including:

[0079] The electrical parameters of the battery cell assembly 100 are collected through the voltage regulation module 502 , and the voltage regulation module 502 is electrically connected between the universal serial bus interface 300 and the battery cell assembly 100 .

[0080] In one embodiment, the second switch module includes a power switch 604 of the universal serial bus interface and a loop switch 605 of the voltage regulation module, and the power switch 604 of the universal serial bus interface and the loop switch 605 of the voltage regulation module are connected in series between the battery cell assembly 100 and the universal serial bus interface 300.

[0081] Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly 100 collected by the second parameter collection module, including: when the electrical parameters of the battery cell assembly 100 collected by the second parameter collection module exceed a preset value, being able to control at least one of the second switch modules to be disconnected.

[0082] In one embodiment, the second switch module further includes a battery protection switch tube 602 and / or a fuse 603 .

[0083] The present disclosure also provides a battery pack protection circuit, the battery pack comprising: a battery cell assembly 100, a control module 200, a charge and discharge interface, and a switch module connected in series between the battery cell assembly 100 and the charge and discharge interface, the switch module comprising a first switch module and a second switch module. The battery pack protection circuit comprises:

[0084] The first protection module includes a first parameter acquisition module. One end of the first parameter acquisition module is electrically connected to the battery cell assembly 100, and the other end is electrically connected to the control module 200, and is used to detect the electrical parameters of the battery cell assembly 100. The electrical parameters include voltage parameters and may also include current parameters. The first parameter acquisition module includes a special application integrated circuit. The special application integrated circuit adopts a battery cell sampling chip 400. The battery cell sampling chip 400 is capable of collecting the electrical parameters of a single cell and a whole package of the battery cell assembly 100. The battery cell sampling chip 400 transmits the collected electrical parameters of a single cell and a whole package of the battery cell assembly 100 to the control module 200 through communication.

[0085] The second protection module includes a second parameter acquisition module electrically connected to the battery cell assembly 100 and the control module 200. The second parameter acquisition module detects the electrical parameters of the battery cell assembly 100. The second parameter acquisition module includes a voltage regulation module 502, one end of the voltage regulation module 502 is electrically connected to the universal serial bus interface 300, and the other end is electrically connected to the battery cell assembly 100, and is used to collect the electrical parameters of a single cell and a whole package of the battery cell assembly 100. The voltage regulation module 502 is also used to adjust the voltage of the battery cell assembly 100 to match the voltage supplied to the universal serial bus interface 300, or to adjust the voltage of the universal serial bus interface 300 to match the voltage supplied to the battery cell assembly 100 according to the control signal of the control module 200. Specifically, the voltage regulation module 502 is a buck or boost chopper (Buck-boost loop). The buck or boost chopper is transmitted to the control module 200 through communication.

[0086] The above embodiments of the present disclosure achieve the following technical effects: by setting the first parameter acquisition module and the second parameter acquisition module to form the first and second circuit protections, setting the battery cell secondary protection chip 501 to form the third circuit protection, and cooperating with the switch modules set at different positions to form multiple acquisition modules and multiple loop switches, even if one of the acquisition circuits and / or one of the switches fails, the circuit fault can still be accurately judged through other acquisition modules and / or switches, and the effect of the circuit protection function can be achieved, thereby improving the accuracy and safety and reliability of the battery pack parameter detection. The voltage regulation module 502 that must be brought by the universal serial bus interface 300 is used to directly realize the voltage detection of the battery cell assembly 100, without the need to set up a voltage detection part separately, and the cost is lower.

[0087] While the disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

[0088] The embodiments of the present disclosure are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present disclosure should be included in the scope of protection of the present disclosure.

[0089] It should be noted that the above describes some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A battery pack, characterized in that: The battery pack comprises: A battery cell assembly, a control module, a charge and discharge interface, a switch module connected in series between the battery cell assembly and the charge and discharge interface, the switch module comprising a first switch module and a second switch module; and, A first protection module, comprising a first parameter acquisition module electrically connected to the battery cell assembly and the control module; the first parameter acquisition module detects electrical parameters of the battery cell assembly, and the control module can control the on and off of at least the first switch module according to the electrical parameters; A second protection module includes a second parameter acquisition module electrically connected to the battery cell assembly and the control module; the second parameter acquisition module detects the electrical parameters of the battery cell assembly, and the control module can control the on and off of at least the second switch module according to the electrical parameters; The node position at which the second protection module detects the electrical parameter is different from the node position at which the first protection module detects the electrical parameter, and / or the position of the first switch module is different from the position of the second switch module.

2. The battery pack according to claim 1, characterized in that: The first parameter acquisition module includes a cell sampling chip, which is electrically connected between the control module and the cell assembly and is used to collect electrical parameters of the cell assembly.

3. The battery pack according to claim 2, characterized in that: The charge and discharge interface includes an electric tool interface, the first switch module includes a charge and discharge switch, the charge and discharge switch is connected in series between the battery cell assembly and the electric tool interface, and is electrically connected to the control module; when the electrical parameters of the battery cell assembly collected by the first parameter acquisition module exceed a preset threshold, the control module can control at least the charge and discharge switch to disconnect.

4. The battery pack according to claim 2, characterized in that: The charging and discharging interface includes a universal serial bus interface, and the second parameter acquisition module includes a voltage regulation module. The voltage regulation module is electrically connected between the universal serial bus interface and the battery cell assembly and is used to collect electrical parameters of the battery cell assembly.

5. The battery pack according to claim 4, characterized in that: The second switch module includes a power switch of a universal serial bus interface and a loop switch of a voltage regulating module, and the power switch of the universal serial bus interface and the loop switch of the voltage regulating module are connected in series between the battery cell assembly and the universal serial bus interface; When the electrical parameter of the battery cell assembly collected by the second parameter collection module exceeds a preset threshold, the control module can control at least one of the second switch modules to be disconnected.

6. The battery pack according to claim 5, characterized in that: The second switch module further includes a battery protection switch tube and / or a fuse, and the battery protection switch tube and / or the fuse are connected in series between the battery cell assembly and the universal serial bus interface.

7. The battery pack according to claim 4, characterized in that: The voltage regulating module is also used to adjust the voltage of the battery cell assembly to match the voltage supplied to the universal serial bus interface, or to adjust the voltage of the universal serial bus interface to match the voltage supplied to the battery cell assembly according to the control signal of the control module.

8. The battery pack according to claim 4, characterized in that: The electrical parameters sampled by the cell sampling chip or the voltage regulating module include at least a single cell voltage and a whole pack voltage.

9. The battery pack according to any one of claims 1 to 8, characterized in that: The battery pack further includes a secondary cell protection chip, which is electrically connected between the control module and the cell assembly and is used to collect electrical parameters of the cell assembly; The battery cell secondary protection chip sets a secondary protection preset threshold, and the secondary protection preset threshold is higher than the preset threshold of the electrical parameters of the first parameter acquisition module and / or the second parameter acquisition module; When the electrical parameter of the battery cell assembly exceeds a preset threshold value of secondary protection, the control module can selectively control at least one switch in the switch module to be disconnected.

10. A battery pack protection method, the battery pack comprising a battery cell assembly, a control module, a charge and discharge interface, and a switch module connected in series between the battery cell assembly and the charge and discharge interface, the switch module comprising a first switch module and a second switch module; and a first protection module and a second protection module, wherein the first protection module includes a first parameter acquisition module and the second protection module includes a second parameter acquisition module, characterized in that: The method comprises: Detecting electrical parameters of the battery cell assembly through the first parameter acquisition module; Detecting electrical parameters of the battery cell assembly through the second parameter acquisition module; Controlling the on and off of at least the first switch module according to the electrical parameters of the battery cell assembly collected by the first parameter collection module; Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly collected by the second parameter collection module; The node position at which the second protection module detects the electrical parameter is different from the node position at which the first protection module detects the electrical parameter, and / or the position of the first switch module is different from the position of the second switch module.

11. The battery pack protection method according to claim 10, characterized in that: The first parameter acquisition module includes a cell sampling chip; Detecting the electrical parameters of the battery cell assembly through the first parameter acquisition module includes: The electrical parameters of the battery cell assembly are detected by the battery cell sampling chip, and the battery cell sampling chip is electrically connected between the control module and the battery cell assembly.

12. The battery pack protection method according to claim 11, characterized in that: The charge and discharge interface includes an electric tool interface, the first switch module includes a charge and discharge switch, the charge and discharge switch is connected in series between the battery cell assembly and the electric tool interface, and is electrically connected to the control module; According to the electrical parameters of the battery cell assembly collected by the first parameter collection module, at least the first switch module is controlled to be turned on and off, including: when the electrical parameters of the battery cell assembly collected by the first parameter collection module exceed a preset threshold, at least the charge and discharge switch can be controlled to be turned off.

13. The battery pack protection method according to claim 10, characterized in that: The charging and discharging interface includes a universal serial bus interface, and the second parameter acquisition module includes a voltage regulation module; Detecting the electrical parameters of the battery cell assembly through the second parameter acquisition module includes: The electrical parameters of the battery cell assembly are collected through the voltage regulation module, and the voltage regulation module is electrically connected between the universal serial bus interface and the battery cell assembly.

14. The battery pack protection method according to claim 13, characterized in that: The second switch module includes a power switch of the universal serial bus interface and a loop switch of the voltage regulating module, and the power switch of the universal serial bus interface and the loop switch of the voltage regulating module are connected in series between the battery cell assembly and the universal serial bus interface; Controlling the on and off of at least the second switch module according to the electrical parameters of the battery cell assembly collected by the second parameter collection module, including: when the electrical parameters of the battery cell assembly collected by the second parameter collection module exceed a preset value, being able to control at least one of the second switch modules to be disconnected.

15. The battery pack protection method according to claim 14, characterized in that: The second switch module also includes a battery protection switch tube and / or a fuse.

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