Battery fast charging device, lithium-ion battery and electronic equipment

Abstract

The present application discloses a battery fast charging device, a lithium-ion battery and an electronic device, wherein a battery fast charging device is characterized in that it includes at least two connectors and a plurality of parallel circuits, each of the connectors is connected to at least one of the circuits, the circuit includes at least a battery cell, a first protector and a second protector, the first protector includes at least a protection chip and a transistor group, the protection chip is connected in parallel with the battery cell, and the protection chip switches the circuit on or off by controlling the transistor group, and at least one of the plurality of parallel circuits is a charge and discharge circuit. The present application uses two separate connectors and two separate charging circuits that do not interfere with each other. When charging with a large current, the charging circuit serves as the main charging circuit and the charge and discharge circuit serves as an auxiliary charging circuit, so that the two chips can charge the battery at the same time during fast charging, thereby avoiding the problems of large heat loss and low efficiency of a single chip.

Description

Technical Field

[0001] The present application generally relates to the field of lithium-ion charging technology, and specifically relates to a battery fast charging device, a lithium-ion battery, and an electronic device. Background Art

[0002] In the 5G era, mobile phone power consumption increases, and batteries develop in the direction of fast charging and large capacity. However, due to structural space constraints, battery capacity is limited. Therefore, fast charging technology has benefited from rapid development. The charging power has developed from the initial 10W to 65W (charging current has changed from 2A to 12A). Fast charging and heat are contradictory. In order to reduce heat loss, on the one hand, the heat loss is reduced by reducing the impedance of the protection board, and on the other hand, the charging path is changed to optimize the charging architecture to reduce heat loss.

[0003] In the existing technology, one way is to increase the effective heat dissipation area of the heat-generating device by increasing the space (width) of the protection board, thereby reducing the temperature rise of the protection board. Another way is to select a device with smaller impedance and reduce the device impedance by connecting multiple devices in parallel, which requires a larger protection board space to place the devices. Another way is to achieve it through the charging path. Generally, a dual IC dual MOS solution is adopted to reduce the device impedance by parallel connection. However, in the existing technology, the positive electrode of the battery cell and the positive electrode of the battery are not completely separated, and the negative electrode of the battery cell and the negative electrode of the battery are not separated either, resulting in the accumulation of current in the hardware area. When achieving fast charging, heat loss is not effectively reduced.

[0004] Therefore, in response to the problems existing in the existing technology, how to more effectively reduce heat loss during fast charging has become a key technical issue that needs to be solved urgently. Summary of the Invention

[0005] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a battery fast charging device, a lithium-ion battery and an electronic device, which change the charging path and optimize the charging architecture, reduce heat loss during fast charging, and lower the temperature rise of the protection plate.

[0006] In the first aspect, the present application provides a battery fast charging device, comprising at least two connectors and multiple parallel circuits, each of the connectors being connected to at least one of the circuits, the circuit comprising at least a battery cell, a first protector and a second protector, the first protector comprising at least a protection chip and a transistor group, the protection chip being connected in parallel with the battery cell, the protection chip connecting or disconnecting the circuit by controlling the transistor group, and at least one of the multiple parallel circuits being a charging and discharging circuit.

[0007] Furthermore, the transistor group includes at least a first transistor and a second transistor, wherein the gate of the first transistor is connected to the DO port of the protection chip, the gate of the second transistor is connected to the CO port of the protection chip, the drain of the first transistor is connected to the drain of the second transistor, the source of the first transistor is connected to the battery cell, and the source of the second transistor is connected to the VM port of the protection chip and the second protector.

[0008] Preferably, the battery comprises a main connector and a secondary connector, wherein the main connector is connected to a charging circuit, and the secondary connector is connected to a charge-discharge circuit, wherein the charging circuit comprises a first protection chip and a first transistor group, and when the first protection chip detects an overcurrent or overvoltage in the charging circuit, the first protection chip controls the first transistor group to disconnect the charging circuit for the battery cell;

[0009] The charge and discharge circuit includes a second protection chip and a second transistor group. When the second protection chip detects overcurrent or overvoltage in the charge and discharge circuit, the second protection chip controls the second transistor group to connect or disconnect the charge and discharge circuit.

[0010] Furthermore, a node formed by connecting the first transistor group in the charging circuit and the second transistor group in the charge and discharge circuit is connected to the negative electrode of the battery cell through a precision resistor.

[0011] Furthermore, the second protector is a temperature fuse.

[0012] Furthermore, the secondary connector is also connected to a protection circuit in parallel with the charging and discharging circuit, and the protection circuit includes a fuse.

[0013] Furthermore, the protection circuit includes a first resistor, a second resistor and a fuse, the first resistor is connected between the positive electrode of the battery cell and the secondary connector; the second resistor and the fuse are connected between the negative electrode of the battery cell and the secondary connector.

[0014] Furthermore, the main connector is also connected to an electric meter circuit, and an electric meter in the electric meter circuit is connected in parallel to both ends of the precision resistor.

[0015] In a second aspect, the present application provides a lithium-ion battery, on which is provided a battery fast charging device as described above.

[0016] In a third aspect, the present application provides an electronic device, on which is provided a battery fast charging device as described above.

[0017] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0018] The battery fast charging device provided in the embodiment of the present application uses two separate connectors and two separate charging circuits that do not interfere with each other. During high-current charging, the charging circuit serves as the main charging circuit and the charging and discharging circuit serves as auxiliary charging, so that the two chips can charge the battery at the same time during fast charging, avoiding the problems of large heat loss and low efficiency of a single chip; at the same time, the impedance of the charging and discharging circuit is small, and physical diversion is adopted in combination with the charging path using impedance matching to reduce heat loss of the protection board. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0020] Figure 1 A schematic structural diagram of a battery fast charging device provided in an embodiment of the present application;

[0021] Figure 2 A circuit diagram of a battery fast charging device provided in an embodiment of the present application;

[0022] Figure 3 A circuit diagram of an electric meter circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0024] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] Lithium batteries are made of materials that protect them from overcharge, over-discharge, overcurrent, short circuits, and ultra-high-temperature charging and discharging. Therefore, lithium batteries and lithium battery components typically include a protective board. This board, comprised of electronic circuitry, accurately monitors the voltage of the lithium battery cells and the current of the charge and discharge circuits in real time, operating in temperatures ranging from -40°C to +85°C, and promptly controls the on / off state of the current circuit. Generally, the protective board is located at the opening of the lithium battery. One side of the board houses positive and negative terminals and electrical components. The positive and negative leads are electrically connected to the positive and negative terminals on the protective board, respectively.

[0026] In the existing technology, battery cell voltage detection is often achieved through fuel gauge collection in the CC segment (constant current mode, testing the change in output voltage when the output current remains unchanged). After switching to PMIC charging, due to PMIC hardware problems, battery cell voltage detection cannot be achieved, resulting in the battery cell starting CV (constant voltage mode, testing the change in output current when the output voltage remains unchanged) before reaching the set voltage.

[0027] Fast-charging battery cells heat up more than regular cells, typically reaching a maximum temperature of around 15°C. This, combined with the heat generated by the motherboard itself, results in excessive heat generation, which can further degrade overall device performance and negatively impact the phone's cycle life. In severe cases, there are safety risks such as the battery back cover scorching or burns, impacting user experience and posing a threat to users. The following table illustrates the heat loss observed at different charging power levels in existing technologies.

[0028] Charging power Into battery current Heat loss 10w 2A 4R 18W 3.6A 12.96R 22.5W 4.5A 20.25R 30W 6A 36R 40W 8A 64R 50W 10A 100R 65W 12A 144R

[0029] Based on the heat loss problem existing in the existing technology, such as Figure 1 As shown, the present application provides a battery fast charging device, comprising at least two connectors and multiple parallel circuits, each of the connectors being connected to at least one of the circuits, the circuit comprising at least a battery cell, a first protector and a second protector, the first protector comprising at least a protection chip and a transistor group, the protection chip being connected in parallel with the battery cell, the protection chip connecting or disconnecting the circuit by controlling the transistor group, and at least one of the multiple parallel circuits being a charging and discharging circuit.

[0030] The transistor group includes at least a first transistor and a second transistor, wherein Figure 2 As shown, the gate of the first transistor is connected to the DO port of the protection chip, the gate of the second transistor is connected to the CO port of the protection chip, the drain of the first transistor is connected to the drain of the second transistor, the source of the first transistor is connected to the battery cell, and the source of the second transistor is connected to the VM port of the protection chip and the second protector.

[0031] It should be noted that the protection chip IC controls the MOS switch to conduct under normal conditions, connecting the battery cell to the external circuit. However, when the battery cell voltage or loop current exceeds a specified value, it immediately controls the MOS switch to shut off, protecting the battery cell. Therefore, the embodiments of the present invention are not limited to protection ICs. The protection IC is merely a name given based on current technology and understanding. Any component or integrated circuit with similar functions should be equivalent to the protection IC.

[0032] It should also be noted that in the following description of the functions of the IC pins, VDD is the positive pole of the IC power supply, VSS is the negative pole of the IC power supply, VM is the overcurrent / short circuit detection terminal, DO is the discharge protection execution terminal, and CO is the charge protection execution terminal; in the circuit diagram, P+ and P- represent the positive and negative poles of the battery connected to the connector; B+ and B- represent the positive and negative poles of the battery; S+ and S- represent the positive and negative poles of the acquisition circuit connected to the connector.

[0033] The second protector can be a thermal cutoff (TCO). A TCO element (THERMAL-CUTOFF), also known as a thermal fuse, is a temperature-sensing circuit cutoff device. A thermal cutoff is used to protect the circuit. When the temperature generated during fast charging exceeds the rated temperature of the fuse itself, it automatically blows to prevent damage caused by overheating.

[0034] In specific settings, an embodiment of the present application provides a battery fast charging device, including a main connector J1 and a secondary connector J2, wherein the main connector J1 is connected to a charging circuit, and the secondary connector J2 is connected to a charging and discharging circuit.

[0035] The charging circuit includes a first protection chip IC1, a first transistor group Q1, and a first TCO. When the first protection chip IC1 detects overcurrent or overvoltage in the charging circuit, the first protection chip IC1 controls the first transistor group Q1 to disconnect the charging circuit for the battery cell.

[0036] The first transistor group includes a first MOS transistor M1 and a second MOS transistor M2, wherein the gate of the first MOS transistor M1 is connected to the DO port of the first protection chip IC1, the gate of the second MOS transistor M2 is connected to the CO port of the first protection chip IC, the drain of the first MOS transistor M1 is connected to the drain of the second MOS transistor M2, the source of the first MOS transistor M1 is connected to the battery cell, and the source of the second MOS transistor M2 is connected to the VM port of the first protection chip IC1 and the first TCO1.

[0037] In addition, the VDD port of the first protection chip IC2 is connected to the positive electrode B+ of the battery cell through a third resistor R3, and the VSS port of the first protection chip IC1 is connected to the negative electrode B- of the battery cell. The source of the second MOS transistor M2 and the VM port of the first protection chip IC1 are also connected to a fourth resistor R4.

[0038] The charge and discharge circuit includes a second protection chip IC2, a second transistor group Q2 and a second TCO2. When the second protection chip IC2 detects overcurrent or overvoltage in the charge and discharge circuit, the second protection chip IC2 controls the second transistor group Q2 to turn on or off the charge and discharge circuit.

[0039] The second transistor Q2 group includes a third MOS transistor M3 and a fourth MOS transistor M4, wherein the gate of the third MOS transistor M3 is connected to the DO port of the second protection chip IC2, the gate of the fourth MOS transistor M4 is connected to the CO port of the second protection chip IC, the drain of the third MOS transistor M3 is connected to the drain of the fourth MOS transistor M4, the source of the third MOS transistor M3 is connected to the battery cell, and the source of the fourth MOS transistor M4 is connected to the VM port of the second protection chip IC2 and the second TCO.

[0040] In addition, the VDD port of the second protection chip IC2 is connected to the positive electrode B+ of the battery cell through the fifth resistor R5, and the VSS port of the second protection chip IC2 is connected to the negative electrode B- of the battery cell.

[0041] The node formed by connecting the source of the first MOS tube M1 and the source of the second MOS tube M2 is connected to the negative electrode B- of the battery cell through a precision resistor RS. The MOS tubes in this embodiment are all implemented using NMOS tubes. It is understandable that in actual application scenarios, PMOS tubes can also be used for implementation, and the present invention does not specifically limit this. A precision resistor is a resistor with high precision, low temperature drift and high reliability. In the embodiment of the present application, the precision resistor can be composed of multiple precision resistors, such as two resistors RS1 and RS2 connected in parallel.

[0042] It should be noted that MOS transistors, or Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), are classified as P-type MOS transistors and N-type MOS transistors. In NMOS, a high-level gate G turns on and a low-level gate turns off. The drain D of NMOS is the input terminal, and the source S is the output terminal. In PMOS, a low-level gate G turns on and a high-level gate turns off. The source S of PMOS transistors is the input terminal, and the drain D is the output terminal.

[0043] As an example, the current detection method of a battery fast-charging device uses a precision resistor RS as a resistor for overcurrent detection. The voltage drop formed by the current flowing through the current sampling resistor RS in the charge and discharge circuit is used to trigger the overcurrent detection comparator inside the battery protection IC. Based on the detected current, it is determined whether there is charging overcurrent or discharging overcurrent. Then, the protection IC turns off the charging switch or discharging switch to complete the charging overcurrent protection and discharging overcurrent protection functions. This can greatly reduce the impedance of the current loop and effectively reduce the heat generated by the charging and discharging circuit.

[0044] In the battery fast-charging device provided by the embodiments of the present application, when the battery voltage is above the over-discharge detection voltage and below the over-charge detection voltage, and the voltage at the VM terminal is above the charger detection voltage but below the over-current / detection voltage (0V), the control IC monitors the voltage difference between the VDD-VSS connection and the VM-VSS connection to control the two MOS transistors. Both the DO and CO terminals are high, and the MOS transistors are in the on state, allowing for free charging and discharging. The third resistor R3 and the fifth resistor R5 limit current, stabilize VDD, and enhance ESD. The fourth resistor R4 and the sixth resistor R6 are current-limiting resistors.

[0045] When the charge and discharge circuit is charging, during the charging process, current flows out from the P+ end of the connector, flows through the positive electrode of the battery cell, then flows out from the negative electrode of the battery cell, flows through the third MOS transistor and the fourth MOS transistor respectively, and then flows to the P- end of the connector, thereby completing the charging of the battery.

[0046] When the charge and discharge circuit discharges, during the discharge process, the current flows out from the positive electrode B+ of the battery cell, flows through the P+ end of the connector, and then flows from the P- end of the connector through the fourth MOS transistor M4 and the third MOS transistor M3, and then to the negative electrode of the battery cell, thereby completing the discharge of the battery.

[0047] It should also be noted that the voltage and current detection method of the battery fast charging device is only illustrated as an example in the embodiments of this application. Regardless of the method for performing voltage and current detection, the current and voltage detection described in this application can be implemented in other specific forms without departing from the spirit or basic characteristics of this application.

[0048] In addition, the secondary connector is also connected to a protection circuit in parallel with the charge and discharge circuit, which includes a fuse. A cell sampling circuit is also connected to the secondary connector, with its connection ports designated S+ and S-. Specifically, the protection circuit includes a first resistor R1, a second resistor R2, and a fuse. The first resistor R1 is connected between the cell's positive terminal B+ and the secondary connector S+; the second resistor R2 and the fuse are connected between the cell's negative terminal B- and the secondary connector S-.

[0049] The first resistor acts as the current-limiting resistor for the sampling circuit. The S+ / S- pins are sensed to the battery cell through the current-limiting resistors. During charging, the PMU uses the S+ / S- pins to determine charging switching conditions and the CV voltage, significantly reducing software complexity and improving voltage sampling accuracy. Furthermore, a protection circuit (Current Fuse) is added to the cell voltage sense path. If the motherboard S+ / S- or P+ / S- pins are short-circuited, the Current Fuse activates to prevent safety risks caused by battery over-discharge.

[0050] Furthermore, the main connector is also connected to a fuel meter circuit, in which a fuel meter is connected in parallel to both ends of the precision resistor, and the fuel meter circuit is used to measure the state of capacity (SOC) of the battery cell.

[0051] The fuel gauge collects the current at the precision resistor and uses this current and time integration to calculate the battery's discharge depth. Then, the current battery capacity can be obtained by subtracting the discharge depth from the initial capacity detected when the battery is turned on. Similarly, the charging current and discharge current can also be used to calculate the battery capacity during charging.

[0052] It should also be noted that Figure 3 What is shown is a circuit diagram of a fuel meter circuit, which is only used for illustrative purposes in the embodiments of the present application. Regardless of how the fuel meter circuit is connected and how the battery cell power is measured, the fuel meter circuit, battery cell power measurement, and battery capacity calculation described in the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application.

[0053] In a second aspect, the present application also provides a lithium-ion battery, comprising a plurality of battery cells, each of which is provided with the battery fast charging device.

[0054] In a specific configuration, the lithium-ion battery is composed of a plurality of battery groups connected in series, each of which may include a plurality of battery cells connected in parallel, and each of which may include a plurality of battery cells connected in parallel.

[0055] In some embodiments, each battery connected in series is treated as a unit and connected to a battery fast charging device; in other embodiments, each battery cell connected in parallel is connected to a battery fast charging device.

[0056] The fast-charging circuit in the embodiment of the present application detects the voltage and current of each battery in the series-connected battery pack to control the charging and discharging process of the lithium battery pack. When the voltage of each battery in the lithium battery pack is between the preset overcharge detection voltage and over-discharge detection voltage, and there is no short circuit at the output, the MOS transistor turns on, and the output terminals P+ and P- output the lithium battery pack voltage, allowing the lithium battery pack to charge and discharge.

[0057] When the voltage of each battery in a lithium battery pack differs due to battery matching or external environmental influences, the embodiment of the present application can also provide a balancing function at the end of the charging process. The specific process is that during the charging process of an unbalanced battery pack, the battery with the highest relative capacity in the lithium battery pack reaches the balanced voltage value first, and the battery with the highest relative capacity is discharged through the balancing resistor. The balancing current is the balancing absorption current value, which reduces the rising rate of the battery voltage. When the battery voltage is lower than the balanced starting voltage, there is no balancing current, thereby compensating for the imbalance of battery capacity in the lithium battery pack and extending the service life of the lithium battery pack.

[0058] In a third aspect, embodiments of the present application further disclose an electronic device equipped with the aforementioned fast battery charging device. The device may be a mobile phone, a computer, a digital broadcasting electronic device, a messaging device, a game console, a tablet device, a medical device, a fitness device, a personal digital assistant, or the like.

[0059] The electronic device includes a charging connector, a charging management chip, a battery, and a load. The charging connector is used to connect to a charging cable. The charging management chip is connected between the charging connector and the battery to control the charging process of the battery. The battery is used to power the load and includes a battery cell and the battery fast charging device described above. The load can be any power-consuming component in the terminal, such as a display, communication module, processor, memory, sensor, speaker, and other power-consuming components.

[0060] This device can be used as a lithium battery fast-charging device for consumer electronic devices, such as mobile phones, watches, various wearable devices, laptops, and tablets. It resides on a separate printed circuit board (PCB) that is connected to the lithium battery cells. Rechargeable batteries in consumer electronic products typically consist of a PCB that carries the lithium battery fast-charging device, the lithium battery cells, and a housing, all forming a lithium battery package to power the consumer electronic device.

[0061] It should be noted that the charging management chip PMIC is a power management unit, a highly integrated power management solution for portable applications. It combines several traditional discrete power management chips, such as low-dropout linear regulators (LDOs) and DC / DC converters, into the power management unit (PMU) of mobile phones. This can achieve higher power conversion efficiency and lower power consumption, as well as fewer components to adapt to the reduced board space and lower costs. As a power management integrated unit for specific main chips of consumer electronics (mobile phones, MP4s, GPS, PDAs, etc.), the charging management chip PMIC can provide all the power supplies required by the main chip at multiple levels and different voltages. The same voltage energy is supplied to different mobile phone working units, such as processors, RF devices, camera modules, etc., so that these units can work normally.

[0062] When the terminal is charging, the current flows as follows: charger → cable → connector → charging management chip → circuit → battery cell; when discharging, the current flows as follows: battery cell → charging and discharging circuit → load.

[0063] The battery fast charging device provided in the embodiment of the present application uses two separate connectors and two separate charging circuits that do not interfere with each other. During high-current charging, the charging circuit serves as the main charging circuit and the charging and discharging circuit serves as auxiliary charging, so that the two chips can charge the battery at the same time during fast charging, avoiding the problems of large heat loss and low efficiency of a single chip; at the same time, the impedance of the charging and discharging circuit is small, and physical diversion is adopted in combination with the charging path using impedance matching to reduce heat loss of the protection board.

[0064] The battery fast charging device provided in the embodiments of the present application can effectively achieve:

[0065] 1. The protection board space is reduced. For example, the 50W protection board is reduced from 7mm to 4mm, which can increase the capacity by about 200mAh (4500mah battery);

[0066] 2. The temperature rise of the protection board is reduced. For example, the temperature rise of the 50W maximum device can be reduced from 35℃ to 30℃;

[0067] 3. Reduce the charging time of the CV segment and the total charging time. At the same time, hardware CV reduces the software complexity;

[0068] 4. Add fuse protection to the discharge circuit to prevent potential safety hazards caused by over-discharge of the battery when the mobile phone is abnormally short-circuited;

[0069] 5. Cost reduction;

[0070] 6. When the ambient temperature is too high, the temperature protection function will be activated to cut off the discharge circuit.

[0071] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art in the art of the present invention. The terms used herein are only for describing specific implementation purposes and are not intended to limit the present invention. Terms such as "setting" appearing in this article can mean that one component is directly attached to another component, or that one component is attached to another component through an intermediate component. Features described in this article in one embodiment can be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0072] The present invention has been described through the above embodiments, but it should be understood that the above embodiments are for illustrative and illustrative purposes only and are not intended to limit the present invention to the described embodiments. Those skilled in the art will appreciate that various variations and modifications may be made based on the teachings of the present invention, and such variations and modifications fall within the scope of protection claimed in the present invention.

Claims

1. A battery fast charging device, characterized in that: The invention comprises at least two connectors and a plurality of parallel circuits, each of the connectors being connected to at least one of the circuits, the circuits comprising at least a battery cell, a first protector and a second protector, the first protector comprising at least a protection chip and a transistor group, the protection chip being connected in parallel with the battery cell, and the protection chip connecting or disconnecting the circuit by controlling the transistor group; the plurality of parallel circuits being electrically connected to the same battery cell, and at least one of the plurality of parallel circuits being a charge-discharge circuit; The at least two connectors include a main connector and a secondary connector, the main connector is connected to a charging circuit, the secondary connector is connected to a charging and discharging circuit, and the secondary connector is further connected to a protection circuit connected in parallel with the charging and discharging circuit; During fast charging, the charging circuit serves as the main charging circuit, and the charging and discharging circuit serves as the auxiliary charging circuit; the charging and discharging circuit is used to provide a discharge current to the load through the battery cell; The charge and discharge circuit is connected to a load, and the charge and discharge circuit allows the battery cell to perform charge and discharge operations.

2. The battery fast charging device according to claim 1, characterized in that: The transistor group includes at least a first transistor and a second transistor, wherein: The gate of the first transistor is connected to the DO port of the protection chip, the gate of the second transistor is connected to the CO port of the protection chip, the drain of the first transistor is connected to the drain of the second transistor, the source of the first transistor is connected to the battery cell, and the source of the second transistor is connected to the VM port of the protection chip and the second protector.

3. The battery fast charging device according to claim 1, characterized in that: The charging circuit includes a first protection chip and a first transistor group. When the first protection chip detects an overcurrent or overvoltage in the charging circuit, the first protection chip controls the first transistor group to disconnect the charging circuit for the battery cell. The charge and discharge circuit includes a second protection chip and a second transistor group. When the second protection chip detects overcurrent or overvoltage in the charge and discharge circuit, the second protection chip controls the second transistor group to disconnect the charge and discharge circuit.

4. The battery fast charging device according to claim 3, characterized in that: A node formed by connecting the first transistor group in the charging circuit and the second transistor group in the charge and discharge circuit is connected to the negative electrode of the battery cell through a precision resistor.

5. The battery fast charging device according to claim 1, characterized in that: The second protector is a temperature fuse.

6. The battery fast charging device according to claim 3, characterized in that: The protection circuit includes a fuse.

7. The battery fast charging device according to claim 6, characterized in that: The protection circuit includes a first resistor, a second resistor and a fuse. The first resistor is connected between the positive electrode of the battery cell and the secondary connector; the second resistor and the fuse are connected between the negative electrode of the battery cell and the secondary connector.

8. The battery fast charging device according to claim 4, characterized in that: The main connector is also connected to an electric meter circuit, and an electric meter in the electric meter circuit is connected in parallel to both ends of the precision resistor.

9. A lithium-ion battery, characterized in that: A battery fast charging device as described in any one of claims 1-8 is arranged thereon.

10. An electronic device, characterized in that: A battery fast charging device as described in any one of claims 1-8 is arranged thereon.

Images