Battery leakage improvement circuit, battery protection board, battery and vehicle

Abstract

The utility model relates to the technical field of battery management, and discloses a battery leakage improvement circuit, a battery protection board, a battery and a vehicle, the battery leakage improvement circuit comprises a control unit and a discharge unit, the control unit is connected with the discharge unit, and the discharge unit is connected in series in a power supply loop; when the control unit turns off the charge and discharge switch in the power supply loop, the control unit outputs a high level signal to the discharge unit so as to drive the discharge unit to be conducted, and virtual voltage in the power supply loop is discharged to the ground. By changing the design of the battery circuit, increasing the discharge channel and discharging the virtual voltage of the power supply loop to the ground, the control unit can enter an automatic power-off state, the standby time of the battery pack under low capacity is prolonged, and over-discharge lithium precipitation swelling of the battery core is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery management technical field, concretely relates to a battery leakage improvement circuit, battery protection board, battery and vehicle. BACKGROUND

[0002] The power meter has high precision, multifunction, simple and convenient use and multiple advantages such as, is suitable for the occasion of various management battery lithium electricity protection. At present, mobile phone double series lithium battery and notebook battery all use power meter to carry out power meter control and protection. The power meter carries out collection and control to the battery, and according to the collection information drive charge-discharge switch MOS pipe (Metal-Oxide-Semiconductor Field-Effect Transistor, gold oxygen half field-effect transistor) to execute protection action.

[0003] However, the existing power meter control and protection design scheme often appears the problem of failure, and the failure mainly comes from charge-discharge switch MOS pipe. The charge-discharge switch MOS pipe causes gate oxide layer micro-damage or crystal etching roughness or epitaxial growth silicon crystal dislocation, and Idss leakage current of MOS pipe appears. And the Idss leakage current of MOS pipe can cause the problem that MOS pipe cannot be completely turned off, and further cause the virtual voltage of battery output end, and the virtual voltage can cause the battery power meter monomer to be unable to enter the automatic shutdown state. Since the root cause of MOS pipe Idss leakage current cannot be completely avoided in the current industry, if the above power meter control and protection design scheme is directly applied to the whole machine, the power meter can not be turned off due to MOS pipe leakage in low power mode, which causes the battery to continue to output, and the cell voltage will drop to 0V, and even produce cell internal lithium precipitation, bulge and other conditions. UTILITY MODEL CONTENTS

[0004] Therefore, the utility model provides a battery leakage improvement circuit, battery protection board, battery and vehicle to solve the problem that the power meter can not be turned off due to MOS pipe leakage in low power mode.

[0005] Firstly, the utility model provides a battery leakage improvement circuit, and the circuit includes: control unit and bleeder unit, wherein,

[0006] The control unit is connected with the bleeder unit, and the bleeder unit is connected in series in the power supply loop;

[0007] When the control unit turns off the charge-discharge switch in the power supply loop, the control unit outputs a high-level signal to the bleeder unit to drive the bleeder unit to conduct, and the virtual voltage in the power supply loop is discharged to the ground.

[0008] The utility model provides a kind of battery leakage improvement circuit, comprising: control unit and bleed unit, wherein, control unit is connected with bleed unit, bleed unit is connected in power supply circuit;When the control unit is turned off the charge-discharge switch in power supply circuit, control unit exports high level signal to bleed unit, to drive bleed unit to turn on, virtual voltage in power supply circuit is discharged to ground.

[0009] In an alternative embodiment, the control unit is further configured to monitor the voltage of the battery cell in the power supply circuit and output a low level signal to the bleed unit when the voltage of the battery cell is 0.

[0010] In an alternative embodiment, the bleed unit comprises a virtual voltage bleed circuit, a control end of the virtual voltage bleed circuit is connected to the control unit, a first end of the virtual voltage bleed circuit is connected to the charge-discharge switch and the output connector respectively, and a second end of the virtual voltage bleed circuit is grounded.

[0011] In an alternative embodiment, the control unit comprises a power gauge, an input pin of the power gauge is connected to the upper computer, a first drive pin of the power gauge is connected to the control end of the charge-discharge switch, a second drive pin of the power gauge is connected to the control end of the virtual voltage bleed circuit, and a voltage detection pin of the power gauge is connected between the first end of the virtual voltage bleed circuit and the output connector.

[0012] In an alternative embodiment, the virtual voltage bleed circuit comprises a first transistor, a first end of the first transistor is connected to the charge-discharge switch and the output connector respectively, a control end of the first transistor is connected to the second drive pin of the power gauge, and a second end of the first transistor is grounded.

[0013] In an alternative embodiment, the virtual voltage bleed circuit is integrated inside the power gauge.

[0014] In an alternative embodiment, the virtual voltage bleed circuit is arranged on an external protection board.

[0015] In the second aspect, the utility model provides a battery protection board comprising the battery leakage improvement circuit of the first aspect or any of the corresponding embodiments.

[0016] By using the battery leakage improvement circuit of the above-mentioned embodiments, the condition of lithium drumming caused by over-discharge of the battery cell is effectively avoided, the failure rate of the battery protection board is reduced, and the single product profit is improved.

[0017] In a third aspect, the utility model provides a battery, including the battery protection board of above -mentioned second aspect or its corresponding any implementation mode.

[0018] By adopting the battery protection plate of the above embodiment, the over-discharge lithium drum situation of the battery is effectively avoided, the battery failure rate is reduced, and the single product profit is improved.

[0019] In a fourth aspect, the utility model provides a vehicle, including the battery of above -mentioned third aspect or its corresponding any implementation mode.

[0020] By adopting the battery of the above embodiment, the over-discharge lithium drum situation of the battery is effectively avoided, the over-discharge lithium drum situation of the battery is effectively avoided, the vehicle failure rate is reduced, and the customer experience is improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the utility model or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description, and obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0022] Figure 1 It is the power meter control and protection design scheme of related art;

[0023] Figure 2 It is the battery leakage improvement circuit schematic diagram according to the utility model embodiment. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantage of the utility model embodiment more clear, the following will combine the drawings in the utility model embodiment, and the technical scheme in the utility model embodiment is clearly and completely described, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiments. Based on the embodiment in the utility model, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the utility model.

[0025] In the description of the utility model, it needs to explain that, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "internal", "external" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as limiting the utility model. In addition, the terms "first", "second" and "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0026] In the description of the utility model, it needs to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be mechanically connected, or it can be electrically connected, it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the communication between two elements, it can be wireless connection, or it can be wired connection. For ordinary skilled persons in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0027] In addition, the technical features involved in the different embodiments of the utility model described below can be combined with each other as long as there is no conflict between them.

[0028] At present, the mobile phone double lithium battery and notebook battery use the electric quantity meter to control and protect the electric quantity meter. Figure 1 As shown in the prior electric quantity meter control and protection design scheme. The electric quantity meter has the advantages of high precision, multifunction, simple and convenient use, etc., and is suitable for various lithium battery management and protection occasions. Specifically, the electric quantity meter uses coulomb counting and high-precision AD collector to provide high-precision measurement results, which is particularly important for fields that need to accurately measure the battery charging and discharging electric quantity. The electric quantity meter monitors parameters such as voltage and current to help users optimize and reasonably use lithium batteries. Moreover, the electric quantity meter is not limited to measuring direct current, but can also perform multiple functions to meet different needs. For example, overvoltage protection, overcharge protection, overdischarge protection, charge overcurrent protection, discharge overcurrent protection, etc. When performing the protection function, the electric quantity meter collects and controls the battery, and drives the charge-discharge switch MOS tube to perform the protection action according to the collected information. The Idss leakage current of the charge-discharge switch MOS tube can cause the MOS tube to be unable to completely turn off, which in turn causes the battery output terminal to generate a virtual voltage, and the virtual voltage can cause the battery electric quantity meter to be unable to enter the automatic shutdown state, resulting in the battery overdischarge and lithium drum.

[0029] The utility model provides a kind of battery leakage improvement circuit, it is applicable to all 3C digital battery. Figure 2As shown, the battery leakage improvement circuit comprises a control unit 1 and a leakage unit 2. The control unit 1 is connected with the leakage unit 2, and the leakage unit 2 is connected in series in the power supply circuit. When the control unit 1 turns off the charge-discharge switch in the power supply circuit, the control unit 1 outputs a high-level signal to the leakage unit 2 to drive the leakage unit 2 to conduct, and the virtual voltage in the power supply circuit is discharged to the ground.

[0030] Specifically, the power supply circuit is composed of a battery cell, a charge-discharge switch and an output connector on which a load is installed. The charge-discharge switch is composed of a plurality of MOS tubes. When the MOS tube cannot be completely turned off, a virtual voltage is generated at the output end of the battery cell, forming a virtual voltage circuit.

[0031] When the power supply circuit is normally operated, the control unit 1 sends a conduction instruction to the control end of the MOS tube of the charge-discharge switch to drive the MOS tube of the charge-discharge switch to conduct. The battery cell outputs a normal working voltage to supply power to the load installed on the output connector. When the control unit 1 receives an automatic shutdown instruction issued by the upper computer, the control unit 1 generates a turn-off instruction to drive the MOS tube of the charge-discharge switch to turn off, thereby cutting off the power supply circuit. However, due to the defects of the MOS tube of the charge-discharge switch, the MOS tube of the charge-discharge switch cannot be completely turned off, and thus a virtual voltage is generated at the output end of the battery cell. At this time, the control unit 1 outputs a high-level signal to the leakage unit 2 to drive the leakage unit 2 to conduct, and the virtual voltage in the power supply circuit is discharged to the ground.

[0032] The utility model provides a kind of battery leakage improvement circuit, comprising: control unit and leakage unit, wherein, control unit is connected with leakage unit, and leakage unit is connected in series in power supply circuit;When the control unit turns off the charge-discharge switch in the power supply circuit, the control unit outputs high-level signal to the leakage unit, to drive the leakage unit to conduct, and the virtual voltage in the power supply circuit is discharged to ground. By changing the design of battery circuit, increase the leakage passage, the virtual voltage of power supply circuit is discharged to ground, can let control unit enter automatic shutdown state, improve battery pack low capacity under standby time, avoid battery over-discharge lithium drum package.And it solves the about three ten-thousandth of line bad return, improves single product profit.

[0033] In an alternative embodiment, the control unit 1 is further configured to monitor the voltage of the battery cell in the power supply circuit, and output a low-level signal to the leakage unit 2 when the voltage of the battery cell is 0.

[0034] Specifically, as shown in Figure 2As shown, the virtual pressure detection point of the control unit 1 is located between the charge-discharge switch MOS tube and the output connector. When the control unit 1 drives the bleed unit 2 to turn on, the power supply loop voltage detection link is started, and the control unit 1 detects whether the battery cell voltage is 0 through the virtual pressure detection point in real time. When the control unit 1 detects that the battery cell voltage is 0, a low-level signal is output to the bleed unit 2. The control unit 1 enters the automatic shutdown state, and the bleed channel is completely turned off.

[0035] In an alternative embodiment, the bleed unit 2 comprises a virtual pressure bleed circuit, a control end of the virtual pressure bleed circuit is connected with the control unit 1, a first end of the virtual pressure bleed circuit is connected with the charge-discharge switch MOS tube and the output connector respectively, and a second end of the virtual pressure bleed circuit is grounded.

[0036] Specifically, as shown in Figure 2 , the virtual pressure bleed circuit comprises a first transistor Q1, a first end of the first transistor Q1 is connected with the charge-discharge switch MOS tube and the output connector respectively, a control end of the first transistor Q1 is connected with a second drive pin of the electric quantity meter, and a second end of the first transistor Q1 is grounded. The first transistor Q1 is a MOS tube.

[0037] In an alternative embodiment, as shown in Figure 2 , the control unit 1 comprises an electric quantity meter, an input pin of the electric quantity meter is connected with the upper computer, a first drive pin of the electric quantity meter is connected with the control end of the charge-discharge switch MOS tube, a second drive pin of the electric quantity meter is connected with the control end in the virtual pressure bleed circuit, and a voltage detection pin of the electric quantity meter is connected between the first end of the virtual pressure bleed circuit and the output connector.

[0038] Specifically, when the power supply loop is normally running, the input pin of the electric quantity meter receives the on signal issued by the upper computer, and then the electric quantity meter generates the on command according to the control signal and outputs a high level to the control end of the charge-discharge switch MOS tube through the first drive pin to drive the charge-discharge switch MOS tube to turn on. The battery cell outputs a normal working voltage to supply power to the load installed on the output connector. The upper computer is not shown in Figure 2 .

[0039] When the power gauge receives the automatic shutdown instruction issued by the upper computer, the power gauge generates a shutdown instruction to drive the charge-discharge switch MOS tube to shut down and cut off the power supply loop. However, due to the defects of the charge-discharge switch MOS tube, the charge-discharge switch MOS tube cannot be completely shut down, and then a virtual voltage is generated at the output end of the battery cell. At this time, the output high level of the second drive pin of the power gauge is connected to the control end of the first transistor Q1 to drive the first transistor Q1 to conduct, and the virtual voltage in the power supply loop is discharged to the ground. The voltage detection pin of the power gauge is connected with the virtual voltage detection point to monitor whether the voltage of the battery cell is 0 in real time. When the power gauge detects that the voltage of the battery cell is 0, the second drive pin of the power gauge outputs a low level to the control end of the first transistor Q1, and the first transistor Q1 is shut down, and the power gauge enters the automatic shutdown state. The duration of the high level of the second drive pin can be set according to the actual situation, but at most, the duration is 15s. The virtual voltage detection point is located between the first end of the first transistor Q1 and the output connector.

[0040] In an alternative embodiment, the virtual voltage discharge circuit can be integrated inside the power gauge or arranged on the external protection board.

[0041] Specifically, as shown in Figure 2 , the virtual voltage discharge circuit is arranged on the external protection board. In addition to the external virtual voltage discharge circuit shown in Figure 2 , the virtual voltage discharge circuit can also be integrated into the power gauge. When the virtual voltage discharge circuit is integrated into the power gauge, the working principle is exactly the same as that of the external virtual voltage discharge circuit, and will not be repeated here.

[0042] The utility model provides a kind of battery protection board, comprising Figure 2 As shown in the battery leakage improvement circuit.

[0043] Specifically, by using Figure 2 As shown in the battery leakage improvement circuit, the over-discharge lithium drum situation of battery cell is effectively avoided, the failure rate of battery protection board is reduced, and the single product profit is improved.

[0044] The utility model provides a kind of battery, comprising the battery protection board of above-mentioned embodiment.

[0045] Specifically, by using the battery protection board of above-mentioned embodiment, the over-discharge lithium drum situation of battery cell is effectively avoided, the failure rate of battery is reduced, and the single product profit is improved.

[0046] The utility model provides a kind of vehicle, comprising the battery of above-mentioned embodiment.

[0047] Specifically, by using the battery of above-mentioned embodiment, the over-discharge lithium drum situation of battery cell is effectively avoided, the failure rate of vehicle is reduced, and customer experience is improved.

[0048] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope of the appended claims.

Claims

1. A battery leakage improvement circuit, characterized in that, The circuit includes: a control unit and a discharge unit, wherein... The control unit is connected to the discharge unit, and the discharge unit is connected in series in the power supply circuit; When the control unit turns off the charging and discharging switch in the power supply circuit, the control unit outputs a high-level signal to the discharge unit to drive the discharge unit to conduct and discharge the virtual voltage in the power supply circuit to ground.

2. The battery leakage improvement circuit according to claim 1, characterized in that, The control unit is also used to monitor the cell voltage in the power supply circuit, and output a low-level signal to the discharge unit when the cell voltage is 0.

3. The battery leakage improvement circuit according to claim 2, characterized in that, The discharge unit includes: a virtual pressure discharge circuit, the control terminal of which is connected to the control unit, the first terminal of which is connected to the charge / discharge switch and the output connector respectively, and the second terminal of which is grounded.

4. The battery leakage improvement circuit according to claim 3, characterized in that, The control unit includes: a fuel meter, the input pin of which is connected to a host computer, the first drive pin of which is connected to the control terminal of a charge / discharge switch, the second drive pin of which is connected to the control terminal of a false pressure relief circuit, and the voltage detection pin of which is connected between the first terminal of the false pressure relief circuit and the output connector.

5. The battery leakage improvement circuit according to claim 4, characterized in that, The false pressure relief circuit includes: a first transistor, the first terminal of the first transistor being connected to a charge / discharge switch and an output connector respectively, the control terminal of the first transistor being connected to the second drive pin of the fuel gauge, and the second terminal of the first transistor being grounded.

6. The battery leakage improvement circuit according to claim 4, characterized in that, The false pressure relief circuit is integrated inside the fuel meter.

7. The battery leakage improvement circuit according to claim 4, characterized in that, The virtual pressure relief circuit is installed on an external protection board.

8. A battery protection board, characterized in that, Includes the battery leakage improvement circuit as described in any one of claims 1-7.

9. A battery, characterized in that, Includes the battery protection board as described in claim 8.

10. A vehicle, characterized in that, Includes the battery as described in claim 9.

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