CN114696378A

CN114696378A - Battery quick charging device, lithium ion battery and electronic equipment

Info

Publication number: CN114696378A
Application number: CN202011580823.8A
Authority: CN
Inventors: 魏学文
Original assignee: Beijing Xiaomi Mobile Software Co Ltd
Current assignee: Beijing Xiaomi Mobile Software Co Ltd
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2022-07-01

Abstract

The application discloses battery fills device, lithium ion battery and electronic equipment soon, wherein, a battery fills device soon, its characterized in that, including two at least connectors and many parallelly connected circuits, each the connector is connected at least one the circuit, the circuit includes electric core, first protector and second protector at least, first protector is at least including protection chip and transistor group, the protection chip with electric core is parallelly connected, the protection chip is through control transistor group realizes switching on or breaking the circuit, have at least one for charge-discharge circuit in many parallelly connected circuits. This application is through two solitary connectors to mutual noninterference's two solitary charging circuit, when heavy current charges, charging circuit is as main charging circuit, and charging and discharging circuit charges as supplementary, and two chips charge for the battery simultaneously when realizing filling soon, have avoided the heat waste of single-chip big, the inefficiency problem.

Description

Battery quick charging device, lithium ion battery and electronic equipment

Technical Field

The present application generally relates to the field of lithium ion charging technology, and in particular, to a battery quick charging device, a lithium ion battery, and an electronic apparatus.

Background

In the 5G era, the power consumption of the mobile phone is increased, the battery is developed towards two directions of quick charge and large capacity, but the battery capacity is limited by the structural space, so that the quick charge technology benefits from quick development, the charge power is developed from the initial 10W to 65W (the charge current is changed from 2A to 12A), and the quick charge and the heat are mutually contradictory; in order to reduce the heat loss, the heat loss is reduced by reducing the impedance of the protection board, and the heat loss is reduced by changing the charging path to optimize the charging structure.

In the prior art, one way is to increase the effective heat dissipation area of the heating 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 impedance of the device by a plurality of parallel connection ways, and a larger protection board space is needed for placing the device; the other mode is realized by a charging path mode, a double-IC double-MOS scheme is generally adopted, and the impedance reduction of a device is realized by parallel connection, but in the prior art, the anode of a battery cell and the anode of a battery are not completely separated, and the cathode of the battery cell and the cathode of the battery are not separated, so that the current in a hardware area is accumulated together. When the quick charge is realized, the heat loss is not effectively reduced.

Therefore, how to achieve more effective reduction of heat loss in the fast charging process is a key technical problem to be solved urgently in view of the problems in the prior art.

Disclosure of Invention

In view of the foregoing defects or shortcomings in the prior art, it is desirable to provide a battery quick-charging device, a lithium ion battery and an electronic device, which change a charging path to optimize a charging framework, reduce heat loss during quick charging, and reduce temperature rise of a protection board.

In a first aspect, the application provides a battery quick charging device, including two at least connectors and many parallelly connected circuits, each the connector is connected at least one the circuit, the circuit includes electric core, first protector and second protector at least, first protector is at least including protection chip and transistor group, the protection chip with electric core is parallelly connected, the protection chip is through control transistor group realizes the switch-on or disconnection the circuit, have at least one for charge-discharge circuit in many parallelly connected circuits.

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

Preferably, the charging circuit comprises a main connector and a secondary connector, the main connector is connected to a charging circuit, and the secondary connector is connected to the charging circuit, wherein the charging circuit comprises a first protection chip and a first transistor group, and when the first protection chip detects overcurrent or overvoltage of the charging circuit, the first transistor group is controlled by the first protection chip to disconnect the charging circuit from the battery cell;

the charging and discharging circuit comprises a second protection chip and a second transistor group, and when the second protection chip detects that the charging and discharging circuit is in overcurrent or overvoltage, the second protection chip controls the second transistor group to be switched on or switched off.

Furthermore, a junction formed by connecting the first transistor group in the charging circuit and the second transistor group in the charging and discharging circuit is connected to the negative electrode of the battery cell through a precision resistor.

Further, the second protector is a temperature fuse.

Further, still be connected with on the inferior connector with the parallelly connected protection circuit of charge-discharge circuit, protection circuit includes the fuse.

Further, the protection circuit comprises a first resistor, a second resistor and a fuse, wherein 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 cell negative electrode and the secondary connector.

Furthermore, the main connector is also connected with an electricity meter circuit, and electricity meters in the electricity meter circuit are connected to two ends of the precision resistor in parallel.

In a second aspect, the present application provides a lithium ion battery, on which a battery quick-charging device as described in any of the above is disposed.

In a third aspect, the present application provides an electronic device, on which the battery quick-charging device as described in any one of the above is disposed.

The technical scheme provided by the embodiment of the application can have the following beneficial effects:

according to the battery quick-charging device provided by the embodiment of the application, through the two independent connectors and the two independent charging circuits which are not interfered with each other, when a large current is charged, the charging circuit is used as a main charging circuit, and the charging and discharging circuit is used as an auxiliary charging circuit, so that two chips can charge the battery at the same time when the battery is quickly charged, and the problems of large heat loss and low efficiency of a single chip are solved; meanwhile, the impedance of the charging and discharging circuit is small, and the heat loss of the protection plate is reduced by physically shunting in an impedance matching mode in combination with the charging path.

Drawings

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

fig. 1 is a schematic structural diagram of a battery quick-charging device according to an embodiment of the present disclosure;

fig. 2 is a circuit diagram of a battery quick-charging device according to an embodiment of the present application;

fig. 3 is a circuit diagram of an electricity meter circuit according to an embodiment of the present application.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The lithium battery is not charged or discharged by overcharge, overdischarge, overcurrent, short circuit and ultrahigh temperature due to the material of the lithium battery, so the lithium battery and the lithium battery component are generally provided with the protection plate. The protection board is composed of an electronic circuit, and can accurately monitor the voltage of the battery core of the lithium battery and the current of the charge-discharge loop in real time in the environment of-40 ℃ to +85 ℃ and control the on-off of the current loop in time. Generally, a protection plate is disposed at an opening of a lithium battery, a positive terminal, a negative terminal, and an electrical component are disposed on one surface of the protection plate, and a positive lead and a negative lead are electrically connected to the positive terminal and the negative terminal on the protection plate, respectively.

In the prior art, the cell voltage detection usually realizes the cell voltage acquisition of a CC section (a constant current mode, the change of output voltage under the condition of testing the output current is not changed) through the electricity meter acquisition, and after the cell voltage acquisition is switched to the PMIC for charging, the voltage detection of the cell cannot be realized due to the hardware problem of the PMIC, so that the CV (constant voltage mode, the change of output current under the condition of testing the output voltage is not changed) is started before the cell reaches the set voltage.

The electric core of quick charge battery rises than ordinary electric core temperature, and the battery maximum temperature that generally fills soon rises about 15 degrees, and mainboard itself is also generating heat in addition, leads to calorific capacity too big, further can make complete machine performance decline, is unfavorable for cell-phone life-cycle, can produce the battery after the lid burn or burn human potential safety hazard when serious, influences user experience and brings the threat for the user. As shown in the table below, the heat loss is measured at different charging powers in the prior art.

Charging power	Current into the battery	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

Based on the heat loss problem that exists among the prior art, as shown in fig. 1, the application provides a battery fast charging device, including two at least connectors and many parallelly connected circuits, each the connector is connected at least one the circuit, the circuit includes electric core, first protector and second protector at least, first protector includes protection chip and transistor group at least, the protection chip with electric core is parallelly connected, the protection chip is through control transistor group realizes the switch-on or breaks the circuit, at least one is charge-discharge circuit among many parallelly connected circuits.

As shown in fig. 2, a gate of the first transistor is connected to a DO port of the protection chip, a gate of the second transistor is connected to a CO port of the protection chip, a drain of the first transistor is connected to a drain of the second transistor, a source of the first transistor is connected to the battery cell, and a source of the second transistor is connected to a VM port of the protection chip and the second protector.

It should be noted that, the protection chip IC controls the MOS switch to be turned on under all normal conditions, so as to turn on the battery cell and the external circuit, and when the battery cell voltage or the loop current exceeds a predetermined value, it immediately controls the MOS switch to be turned off, so as to protect the safety of the battery cell. Therefore, the embodiments of the present invention are not limited to the protection IC, which is only a name given by the current technology and cognition, and any component or integrated circuit with similar functions should be equivalent to the protection IC.

It should be further noted that, in the following description of the functions of each pin of the IC, VDD is the positive electrode of the IC power supply, VSS is the negative electrode of the IC power supply, VM is the overcurrent/short circuit detection end, DO is the discharge protection execution end, and CO is the charge protection execution end; in the circuit diagram, P + and P-represent the positive and negative poles of the battery connected by the connector; b + and B-represent the positive electrode and the negative electrode of the battery; and S + and S-represent the positive pole and the negative pole of the acquisition circuit connected with the connector.

Wherein the second protector can be arranged as a temperature fuse TCO. The TCO element (THERMAL-CUTOFF), also called a temperature fuse, is a temperature-sensitive circuit breaker. The temperature fuse is used for protecting a circuit, and when the temperature generated during quick charging exceeds the rated temperature of the fuse, the temperature fuse can be automatically fused, so that the damage caused by overheating of the temperature is prevented.

When specifically arranged, the embodiment of the application provides a battery quick-charging device which comprises 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.

The charging circuit comprises a first protection chip IC1, a first transistor group Q1 and a first TCO, and when the first protection chip IC1 detects overcurrent or overvoltage of the charging circuit, the first protection chip IC1 controls the first transistor group Q1 to disconnect the charging circuit from the battery cell.

The first transistor group comprises a first MOS transistor M1 and a second MOS transistor M2, wherein the grid electrode of the first MOS transistor M1 is connected with the DO port of the first protection chip IC1, the grid electrode of the second MOS transistor M2 is connected with the CO port of the first protection chip IC, the drain electrode of the first MOS transistor M1 is connected with the drain electrode of the second MOS transistor M2, the source electrode of the first MOS transistor M1 is connected with the battery cell, and the source electrode of the second MOS transistor M2 is connected with the VM port of the first protection chip IC1 and the first TCO 1.

In addition, a VDD port of the first protection chip IC2 is connected to a positive electrode B + of the battery cell through a third resistor R3, and a VSS port of the first protection chip IC1 is connected to a 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 further connected with a fourth resistor R4.

The charging and discharging circuit comprises a second protection chip IC2, a second transistor group Q2 and a second TCO2, and when the second protection chip IC2 detects overcurrent or overvoltage of the charging and discharging circuit, the second protection chip IC2 controls the second transistor group Q2 to switch on or switch off the charging and discharging circuit.

The second transistor Q2 set 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.

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

And a node formed by connecting the source electrode of the first MOS transistor M1 and the source electrode of the second MOS transistor M2 is connected to the cathode B-of the battery cell through a precision resistor RS. The MOS transistors in this embodiment are all implemented by NMOS transistors, and it can be understood that in an actual application scenario, the MOS transistors may also be implemented by PMOS transistors, which is not specifically limited to this invention. The precision resistor is a resistor with high precision, low temperature drift and high reliability; in the embodiment of the present application, the precision resistor may be composed of a plurality of precision resistors, for example, two resistors RS1 and RS2 connected in parallel.

The MOS Transistor is a Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET), which is referred to as a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The MOS tube is divided into a P-type MOS tube and an N-type MOS tube, the NMOS is a grid G which is switched on at a high level and switched off at a low level, a drain D of the NMOS is an input end, and a source S of the NMOS is an output end; the PMOS is that grid G is switched on at low level and switched off at high level, and a source S of a PMOS tube is an input end and a drain D is an output end.

As an exemplary illustration, the current detection method of the battery quick charging device is to use a precision resistor RS as a resistor to perform overcurrent detection, and trigger an overcurrent detection comparator inside the battery protection IC by using a voltage drop formed by a current sampling resistor RS through which a current flows through the charging and discharging loop. And judging whether charging overcurrent or discharging overcurrent exists according to the detection current, and further switching off a charging switch or a discharging switch by the protection IC to finish the functions of charging overcurrent protection and discharging overcurrent protection, so that the impedance of a through-flow loop can be greatly reduced, and the heating of a charging and discharging loop can be effectively reduced.

According to the battery quick-charging device provided by the embodiment of the application, the battery voltage is above the overdischarge detection voltage, below the overcharge detection voltage, the voltage of the VM terminal is above the charger detection voltage, and under the condition that the overcurrent/detection voltage is below (OV), the control IC controls the two MOS tubes by monitoring the voltage difference connected between VDD-VSS and the voltage difference between VM-VSS, the DO end and the CO end are both in high level, the MOS tubes are in a conducting state, and then the charging and the discharging can be freely carried out. The third resistor R3 and the fifth resistor R5 play a role in limiting current, stabilizing VDD and strengthening ESD; the fourth resistor R4 and the sixth resistor R6 are current limiting resistors.

When the charging and discharging circuit is charged, current flows out from the P + end of the connector in the charging process, flows through the positive electrode of the battery cell, flows out from the negative electrode of the battery cell, respectively flows through the third MOS tube and the fourth MOS tube, and then flows to the P-end of the connector, so that the charging of the battery is completed.

When the charging and discharging circuit discharges, current flows out of the positive electrode B + of the battery cell respectively in the discharging process, flows through the P + end of the connector, then flows through the fourth MOS tube M4 and the third MOS tube M3 respectively from the P-end of the connector, and then flows to the negative electrode of the battery cell, so that the discharging of the battery is completed.

It should be further noted that the voltage and current detection method of the battery quick charging device is only exemplified in the embodiments of the present application, and no matter how the voltage and current detection is performed, the current and voltage detection described in the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

In addition, still be connected with on the inferior connector with the parallelly connected protection circuit of charge-discharge circuit, protection circuit includes Fuse. And the secondary connector is connected with a cell sampling circuit, and the wiring ports of the secondary connector are respectively expressed as S + \ S-. Specifically, the protection circuit includes a first resistor R1, a second resistor R2, and a Fuse, where the first resistor R1 is connected between the cell positive electrode B + and the secondary connector S +; the second resistor R2 and the Fuse are connected between the cell negative electrode B-and the secondary connector S-.

The first resistor is used as a current-limiting resistor of the sampling circuit, the S +/S-is transmitted to the battery cell through the current-limiting resistor, and when the battery is charged, the PMU can make charging switching condition judgment and CV voltage through the S +/S-, so that software complexity can be greatly reduced, and accuracy of voltage sampling can be improved. In addition, a protection circuit (Current Fuse) is added to the cell voltage Sense path for protection, and when the main board is in S +/S-, P +/S-short circuit, the Current Fuse starts protection to prevent the safety risk caused by over-discharge of the battery.

Furthermore, the main connector is also connected with a fuel gauge circuit, a fuel gauge in the fuel gauge circuit is connected in parallel to two ends of the precision resistor, and the fuel gauge circuit is used for measuring the capacity percentage (SOC) of the battery cell.

The electricity meter collects the current at the precise resistor, the discharge depth of the battery can be converted by utilizing the current and time integral, the discharge depth is subtracted from the capacity initially detected when the battery is started, the current battery capacity can be obtained, and the battery capacity during charging can also be converted by utilizing the charging current and the discharging current in the same way.

It should be noted that fig. 3 is a circuit diagram of a fuel gauge circuit, which is only exemplary in the embodiment of the present application, and no matter how the fuel gauge circuit is connected and the quantity of electricity of the battery cell is measured, the fuel gauge circuit, the quantity of electricity of the battery cell, and the calculation of the battery capacity described in the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

In a second aspect, the present application further provides a lithium ion battery, which includes a plurality of battery cells, and each battery cell is provided with the battery quick charging device.

In a specific configuration, the lithium ion battery is composed of a plurality of groups of batteries connected in series, each group of batteries may include a plurality of battery cells connected in parallel, and each group of battery cells is composed of a plurality of battery cells connected in parallel.

In some embodiments, the batteries connected in series are respectively used as a unit, and one battery quick-charging device is connected; in other embodiments, a battery quick-charging device is connected to each of the cells connected in parallel.

The voltage and the current of each battery in the series battery pack are respectively detected through the quick charging circuit in the embodiment of the application, and the charging and discharging process of the lithium battery pack is controlled. The voltage of each battery in the lithium battery pack is between the preset overcharge detection voltage and the over-discharge detection voltage, and when no short circuit phenomenon is output, the MOS tube is conducted, the output end P + and the output end P-output voltage of the lithium battery pack allow the lithium battery pack to carry out charging and discharging operations.

When the voltage of each battery in the lithium battery pack is different due to the matching of the batteries or the influence of the external environment, the embodiment of the application can also realize the purpose of providing an equalization function at the tail end of the charging process, and the specific process is that the unbalanced battery pack discharges the battery with the highest relative capacity at the first equalization voltage value in the charging process, the equalization current is the equalization absorption current value, so that the rising speed of the voltage of the battery is reduced, and when the voltage of the battery is lower than the equalization starting voltage, no equalization current exists, so that the imbalance of the battery capacity in the lithium battery pack is compensated, and the service life of the lithium battery pack is prolonged.

In a third aspect, an embodiment of the present application further discloses an electronic device, where the battery quick-charging device is provided as described above. Which may be a mobile phone, computer, digital broadcast electronics, messaging device, game console, tablet device, medical device, fitness device, personal digital assistant, or the like.

The electronic equipment comprises a charging connector, a charging management chip, a battery and a load, wherein the charging connector is used for connecting 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 for supplying power to the load, and the battery comprises a battery core and a battery quick-charging device. The load may be any powered component within the terminal, such as a display, a communication module, a processor, a memory, a sensor, and a speaker, among other powered components.

The lithium battery quick-charging device can be used as a lithium battery quick-charging device of consumer electronic equipment, such as various wearable devices including mobile phones and watches, and lithium battery quick-charging devices including notebook computers and tablet computers, the lithium battery quick-charging device exists on an independent Printed Circuit Board (PCB), and the PCB is connected with a battery core of the lithium battery. The rechargeable battery in the consumer electronics product generally refers to a lithium battery packaging bag formed by a PCB carrying a lithium battery quick charging device, a core of a lithium battery and a shell, and is used for supplying power to the consumer electronics equipment.

It should be noted that, the PMIC is a power management unit, and a power management scheme with high integration and for portable applications is to integrate several types of traditionally discrete power management chips, such as a low dropout regulator (LDO) and a direct current/direct current converter (DC/DC), into a Power Management Unit (PMU) of a mobile phone, so that higher power conversion efficiency and lower power consumption can be achieved, and fewer components are required to adapt to a reduced board level space, and the cost is lower; the PMIC is used as a power management integrated unit matched with a specific main chip of consumer electronics (such as a mobile phone, an MP4, a GPS, a PDA and the like), can provide all power supplies with different voltages of multiple grades and different levels required by the main chip, and supplies energy with the same voltage to different mobile phone working units, an image processor, a radio frequency device, a camera module and the like, so that the units can work normally.

The current flows when the terminal is charged as follows: charger → cable → connector → charging management chip → circuit → electric core; the current flows during discharge as follows: cell → charge and discharge circuit → load.

The battery quick charging device provided by the embodiment of the application can effectively realize that:

1. the space of the protective plate is reduced, for example, the 50W protective plate is reduced from 7mm to 4mm, and the capacity of 200mAh (4500mAh battery) can be increased;

2. the temperature rise of the protection plate is reduced, for example, the temperature of a 50W highest device can be reduced to 30 ℃ from 35 ℃;

3. the charging time of the CV section is reduced, the total charging time is reduced, and meanwhile, the software complexity is reduced by the hardware CV;

4. the discharging loop is added with fuse protection, so that potential safety hazards caused by over-discharge of a battery when the mobile phone is abnormally short-circuited are guaranteed;

5. the cost is reduced;

6. when the environmental temperature is too high, the temperature protection can be started, and the discharging loop is cut off.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Terms such as "disposed" and the like, as used herein, may refer to one element being directly attached to another element or one element being attached to another element through intervening elements. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the scope of the described embodiments. It will be appreciated by those skilled in the art that many variations and modifications may be made to the teachings of the invention, which fall within the scope of the invention as claimed.

Claims

1. The utility model provides a battery fills device soon, its characterized in that includes two at least connectors and many parallelly connected circuits, each the connector is connected at least one the circuit, the circuit includes electric core, first protector and second protector at least, first protector includes protection chip and transistor group at least, the protection chip with electric core is parallelly connected, the protection chip is through control transistor group realizes the switch-on or breaks the circuit, at least one is charge-discharge circuit among many parallelly connected circuits.

2. The battery quick-charging device according to claim 1, wherein the transistor group includes at least a first transistor and a second transistor, wherein,

the grid electrode of the first transistor is connected with a DO port of the protection chip, the grid electrode of the second transistor is connected with a CO port of the protection chip, the drain electrode of the first transistor is connected with the drain electrode of the second transistor, the source electrode of the first transistor is connected with the battery cell, and the source electrode of the second transistor is connected with a VM port of the protection chip and the second protector.

3. The battery quick-charging device according to claim 1, comprising a main connector connected to a charging circuit and a sub-connector connected to a charging and discharging circuit, wherein,

the charging circuit comprises a first protection chip and a first transistor group, and when the first protection chip detects overcurrent or overvoltage of the charging circuit, the first transistor group is controlled by the first protection chip to disconnect the charging circuit for the battery cell;

the charging and discharging circuit comprises a second protection chip and a second transistor group, and when the second protection chip detects that the charging and discharging circuit is in overcurrent or overvoltage, the second protection chip controls the second transistor group to disconnect the charging and discharging circuit.

4. The battery quick-charging device according to claim 3, wherein a junction formed by connecting the first transistor group in the charging circuit and the second transistor group in the charging and discharging circuit is connected to the negative electrode of the battery cell through a precision resistor.

5. The battery quick-charging device according to claim 1, wherein the second protector is a thermal fuse.

6. The battery quick-charging device according to claim 3, wherein a protection circuit connected in parallel with the charging and discharging circuit is further connected to the secondary connector, and the protection circuit comprises a fuse.

7. The battery quick-charging device according to claim 6, wherein the protection circuit comprises a first resistor, a second resistor and a fuse, and the first resistor is connected between the cell positive electrode and the secondary connector; the second resistor and the fuse are connected between the cell negative electrode and the secondary connector.

8. The battery quick-charging device according to claim 3, wherein a fuel gauge circuit is further connected to the main connector, and a fuel gauge in the fuel gauge circuit is connected in parallel to two ends of the precision resistor.

9. A lithium ion battery, characterized in that it is provided with a battery quick-charging device according to any one of claims 1-8.

10. An electronic device, characterized in that it is provided with a battery quick-charging device according to any one of claims 1-8.