CN114256896A

CN114256896A - Battery pack, direct current tool and direct current tool assembly

Info

Publication number: CN114256896A
Application number: CN202011009083.2A
Authority: CN
Inventors: 陈飞; 章飞鹏; 陈增
Original assignee: Suzhou Cleva Electric Appliance Co Ltd
Current assignee: Suzhou Cleva Electric Appliance Co Ltd
Priority date: 2020-09-23
Filing date: 2020-09-23
Publication date: 2022-03-29
Also published as: WO2022062029A1

Abstract

The invention discloses a battery pack, a direct current tool and a direct current tool assembly. The battery package is used for supplying power to direct current instrument, and the battery package includes: the output assembly is detachably and electrically connected with the direct current tool; at least two voltage output branches; each of the voltage output branches includes: the electric core group; the switch module is connected between the electric core group and the output assembly; the battery cell parameter detection module is electrically connected with the battery cell group; the battery pack further includes: a load type detection module; the control module is electrically connected with the battery cell parameter detection module and the load type detection module; wherein the output assembly connects each of the voltage output branches in parallel when electrically connected to a first type of DC tool and connects each of the voltage output branches in series when electrically connected to a second type of DC tool. The invention can improve the universality of the battery pack.

Description

Battery pack, direct current tool and direct current tool assembly

Technical Field

The embodiment of the invention relates to the technical field of batteries, in particular to a battery pack, a direct current tool and a direct current tool assembly.

Background

Currently, for the purpose of portability, power battery packs have been widely used in dc tools such as electric drills, lawn mowers, electric saws, electric grinders, and the like. The existing direct current tools are various in types, different direct current tools are different in performance parameters, and different in required power supply voltage, so that battery packs with different output voltages need to be matched. Furthermore, the loads of dc tools powered by different voltages or the same voltage may be different, so that the resulting discharge currents are also different, and therefore the battery pack needs to be adapted to different protection points for different loads.

In the prior art, if direct current tool products with different voltage and current requirements exist, battery packs with different output voltages and different current protection points must be prepared, and the use mode causes the increase of use cost. And with the increase of the types of the direct current tools, the number of the battery packs to be prepared is correspondingly increased, which brings inconvenience to the storage and carrying of the battery packs. Therefore, the conventional battery pack has a problem of poor versatility.

Disclosure of Invention

The embodiment of the invention provides a battery pack, a direct current tool and a direct current tool assembly, which are used for improving the universality of the battery pack.

In a first aspect, an embodiment of the present invention provides a battery pack, configured to supply power to a dc tool, where the battery pack includes:

an output assembly removably electrically connected with the DC tool;

at least two voltage output branches, wherein each of the voltage output branches comprises:

the electric core group;

the switch module is connected between the cell group and the output assembly and is used for switching on or switching off the connection between the cell group and the output assembly according to a control signal;

the battery cell parameter detection module is electrically connected with the battery cell group and is used for detecting the electrical parameters of the battery cell group and outputting the electrical parameters;

the battery pack further includes:

the load type detection module is used for detecting the load of the direct current tool electrically connected with the output assembly and outputting a detection signal;

the control module is electrically connected with the battery cell parameter detection module and the load type detection module and is used for generating a control signal according to the electrical parameter and the detection signal so as to control the switch module to be switched on or switched off;

when the output assembly is electrically connected with a first type of direct current tool, the voltage output assembly outputs the voltage of each voltage output branch circuit after being connected in parallel to the first type of direct current tool, and when the output assembly is electrically connected with a second type of direct current tool, the voltage of each voltage output branch circuit after being connected in series is output to the second type of direct current tool.

Optionally, the control module is configured to determine a protection threshold according to the detection signal, determine whether the electrical parameter reaches the protection threshold, and generate a control signal to control the switch module to turn off when the electrical parameter reaches the protection threshold.

Optionally, when the output assembly is electrically connected with the first type of dc tool, the load type detection module outputs a first detection signal;

when the output assembly is electrically connected with the second type of direct current tool, the load type detection module outputs a second detection signal;

wherein the first detection signal is different from the second detection signal and the guard threshold determined from the first detection signal is different from the guard threshold determined from the second detection signal.

Optionally, the switch module comprises: the circuit comprises a first resistor, a second resistor, a third resistor, an optical coupler, a first triode and a first MOS (metal oxide semiconductor) tube;

the first end of the first resistor is a control end of the switch module and is electrically connected with the control module; the second end of the first resistor is electrically connected with the first input end of the optical coupler, the second input end of the optical coupler is connected with a first ground signal, the first output end of the optical coupler is respectively and electrically connected with the base electrode of the first triode and the first end of the second resistor, the second pole of the first triode is connected with a second ground signal, and the first pole of the first triode is respectively and electrically connected with the grid electrode of the first MOS transistor and the second end of the third resistor; the first electrode of the first MOS tube is the second end of the switch module and is electrically connected with the output assembly; the second pole of the first MOS tube is the first end of the switch module and is electrically connected with the electric core group; the second end of the second resistor and the first end of the third resistor are both connected with a first voltage;

alternatively, the switch module includes: the fourth resistor, the fifth resistor, the sixth resistor, the seventh resistor, the second triode, the third triode and the second MOS tube;

the first end of the fourth resistor is the control end of the switch module and is electrically connected with the control module; a second end of the fourth resistor is electrically connected with a first end of the fifth resistor and a base electrode of the second triode respectively, a second end of the fifth resistor, a second pole of the second triode and a second pole of the third triode are all connected with a third ground signal, a first pole of the second triode is electrically connected with a base electrode of the third triode and a first end of the sixth resistor respectively, and a first pole of the third triode is electrically connected with a grid electrode of the second MOS transistor and a second end of the seventh resistor respectively; the first electrode of the second MOS tube is the second end of the switch module and is electrically connected with the output assembly; the second pole of the second MOS tube is the first end of the switch module and is electrically connected with the electric core group; and the second end of the sixth resistor and the first end of the seventh resistor are both connected with a second voltage.

Optionally, the load type detecting module includes: a tenth resistor and an eleventh resistor;

a first end of the tenth resistor is used for inputting a voltage signal; a second end of the tenth resistor is an input end of the load type detection module and is used for being electrically connected with the direct current tool; a first end of the eleventh resistor is electrically connected with a second end of the tenth resistor; and a second end of the eleventh resistor is used as an output end of the load type detection module and is electrically connected with the control module.

Optionally, the cell parameter detection module includes: the battery cell management chip comprises a battery cell management chip and a battery cell current detection unit;

the battery cell management chip is electrically connected with the battery cell group and the control module; the first end and the second end of the cell current detection unit are electrically connected with the cell management chip; the cell current detection unit is used for detecting the current of the cell group; the electrical parameter comprises the current of the electric core group.

Optionally, the cell current detection unit includes: a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a first capacitor, a second capacitor and a third capacitor;

a first end of the twelfth resistor is electrically connected with a first end of the thirteenth resistor and a second end of the fourteenth resistor respectively; a second end of the twelfth resistor is electrically connected with a second end of the thirteenth resistor and a second end of the fifteenth resistor respectively; a first end of the fourteenth resistor is electrically connected to the first end of the first capacitor and the first end of the third capacitor, respectively, and serves as a first end of the cell current detection unit; a first end of the fifteenth resistor is electrically connected with a second end of the second capacitor and a second end of the third capacitor respectively, and serves as a second end of the cell current detection unit; and the second end of the first capacitor and the first end of the second capacitor are both connected with a fourth ground signal.

Optionally, the battery cell group comprises at least two battery cells connected in series;

and the positive electrode of the battery cell is correspondingly and electrically connected with the voltage detection end of the battery cell management chip.

In a second aspect, an embodiment of the present invention provides a dc tool, including an identification resistor, a load type output terminal, and a power supply input terminal;

the identification resistor is electrically connected with the load type output end, the load type output end is used for being electrically connected with the load type detection module in the battery pack provided by the first aspect, and the power supply input end is used for being electrically connected with the output assembly of the battery pack.

In a third aspect, embodiments of the present invention provide a dc tool assembly, including a battery pack as provided in the first aspect and a dc tool as provided in the second aspect;

the load type output end in the direct current tool is electrically connected with the load type detection module in the battery pack, and the power supply input end in the direct current tool is electrically connected with the output assembly of the battery pack.

According to the battery pack provided by the embodiment of the invention, at least two voltage output branches are arranged, each voltage output branch comprises the electric core group, and when the battery pack is used, the output assembly is utilized to control the series-parallel connection relation among the electric core groups, so that different voltage outputs are realized, and the applicability of the battery pack is improved. By arranging the load type detection module, a detection signal is formed according to the access load and is transmitted to the control module, so that the control signal formed by the control module contains the information of the protection point. That is to say, this battery package can dispose the corresponding protection point of output current according to the load of external direct current instrument, and further the suitability of having improved the battery package. Therefore, compared with the prior art, the embodiment of the invention improves the universality of the battery pack, so that one battery pack can be applied to different direct current tools, the utilization rate of the battery pack is further improved, the cost is reduced, and the battery pack is convenient for a user to carry.

Drawings

Fig. 1 is a schematic circuit diagram of a battery pack according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a battery pack according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a different power outlet provided in an embodiment of the present invention;

FIG. 4 is a schematic view illustrating the connection of a plug assembly according to an embodiment of the present invention;

fig. 5 is a schematic view illustrating the connection of another electric core assembly according to the embodiment of the present invention;

fig. 6 is a schematic circuit diagram of a switch module according to an embodiment of the present invention;

fig. 7 is a schematic circuit diagram of another switch module according to an embodiment of the present invention;

fig. 8 is a schematic circuit diagram of another switch module according to an embodiment of the present invention;

fig. 9 is a schematic circuit diagram of another switch module according to an embodiment of the present invention;

fig. 10 is a schematic circuit diagram of a load type detection module according to an embodiment of the present invention;

fig. 11 is a schematic circuit structure diagram of a cell parameter detection module according to an embodiment of the present invention;

fig. 12 is a schematic circuit structure diagram of another cell parameter detection module according to an embodiment of the present invention;

FIG. 13 is a schematic structural diagram of a DC tool according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a dc tool assembly according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

The embodiment of the invention provides a battery pack. Fig. 1 is a schematic circuit diagram of a battery pack according to an embodiment of the present invention. As shown in fig. 1, the battery pack includes: the output device 150 is connected to at least two voltage output branches.

Wherein the output assembly 150 is removably electrically connected to the dc tool. Each voltage output branch comprises: the battery cell group, the switch module and the battery cell parameter detection module. The switch module is connected between the electric core group and the output assembly and used for switching on or switching off the connection between the electric core group and the output assembly according to the control signal. The battery cell parameter detection module is electrically connected with the battery cell group and used for detecting the electrical parameters of the battery cell group and outputting the electrical parameters.

The battery pack further includes: a load type detection module 120 and a control module 110. The load type detection module 120 is used for detecting a load of a dc tool electrically connected to the output assembly 150 and outputting a detection signal. The control module 110 is electrically connected to the cell parameter detection module and the load type detection module 120, and is configured to generate a control signal according to the electrical parameter and the detection signal to control the switch module to be turned on or off.

The output component 150 outputs the voltage of each voltage output branch connected in parallel to the first type of dc tool when electrically connected to the first type of dc tool, and outputs the voltage of each voltage output branch connected in series to the second type of dc tool when electrically connected to the second type of dc tool.

Dc tools include tools powered by a dc power source, which may be power tools such as drills and the like; tools such as vacuum cleaners, cleaning machines, etc. may also be cleaned.

In fig. 1, the structure of the battery pack is described by taking the example of including two voltage output branches. The battery pack includes a first voltage output branch 130 and a second voltage output branch 140. The first voltage output branch 130 includes a first cell group 131, a first switch module 132, and a first cell parameter detection module 133; the first connection end of the first voltage output branch 130 is P11 and is electrically connected with the first cell group 131; the second connection terminal is P12 and is electrically connected to the first switch module 132. The second voltage output branch 140 includes a second cell group 141, a second switch module 142, and a second cell parameter detection module 143; the first connection end of the second voltage output branch 140 is P21 and is electrically connected with the second cell group 141; the second connection terminal is P22 and is electrically connected to the second switch module 142. Accordingly, the output assembly 150 includes four terminals for removably connecting with a dc tool. The first terminal T11 of the output module 150 is electrically connected to the first connection terminal P11 of the first voltage output branch 130, the second terminal T12 is electrically connected to the second connection terminal P12 of the first voltage output branch 130, the third terminal T21 is electrically connected to the first connection terminal P21 of the second voltage output branch 140, and the fourth terminal T22 is electrically connected to the second connection terminal P22 of the second voltage output branch 140.

The voltage switching principle of the battery pack is as follows: as the electric equipment, the direct current tools requiring different power supply voltages have different power sockets. When different power sockets are connected with the output assembly 150, the series-parallel relation among the electric core groups is adjusted to obtain different output voltages. The method comprises the following specific steps:

fig. 2 is a schematic structural diagram of a battery pack according to an embodiment of the present invention; fig. 3 is a schematic structural diagram of different power sockets according to an embodiment of the present invention. Referring to fig. 2 and 3, the battery including two electric core packs will be explained as an example.

As shown in FIG. 2, the battery pack includes two electric core groups (an upper electric core group 510 and a lower electric core group 520, respectively). The output element 530 includes a first terminal 511, a second terminal 512, a third terminal 521 and a fourth terminal 522. Optionally, the first connection end of the upper electric core group 510 is an anode output end of the upper electric core group 510, and is electrically connected with the first end 511 of the output assembly 530; the second connecting end of the upper electric core group 510 is the negative electrode output end of the upper electric core group 510, and is electrically connected with the second end 512 of the output component 530. The first connecting end of the lower electric core group 520 is the positive electrode output end of the lower electric core group 520 and is electrically connected with the third end 521 of the output component 530; the second connection end of the lower electric core set 520 is a negative output end of the lower electric core set 520, and is electrically connected to the fourth end 521 of the output assembly 530.

As shown in fig. 3, when the external dc tool requires a low voltage output voltage, the power outlet is in the form of a first power outlet 610. At this time, the dc tool requires two electric core sets to be connected in parallel to output the power supply voltage. For example, each battery pack can provide 18V voltage, and the two battery packs are connected in parallel, so that the battery pack outputs 18V voltage. The first power outlet 610 includes a first input terminal 611, a second input terminal 612, a third input terminal 613, a fourth input terminal 614, a first output terminal 615, and a second output terminal 616. The first input terminal 611 and the first output terminal 615 of the first power socket 610 are two ends of the same insert; the fourth input terminal 614 and the second output terminal 616 are two ends of the same insert sheet.

In use, in the first power socket 610, the first input terminal 611 is correspondingly connected to the first end 511 of the output component 530; the second input terminal 612 is correspondingly connected with the third end 521 of the output component 530; the third input terminal 613 is correspondingly connected with the fourth terminal 522 of the output assembly 530; the fourth input terminal 614 is correspondingly connected to the second end 512 of the output component 530. The insert sheet corresponding to the first input terminal 611 is connected with the insert sheet corresponding to the second input terminal 612; the insert sheet corresponding to the third input terminal 613 is connected with the insert sheet corresponding to the fourth input terminal 614; so that the upper electric core group 510 and the lower electric core group 520 are connected in parallel as shown in fig. 4. Eventually causing the first power outlet 610 to output 18V to the dc tool through the first output terminal 615 and the second output terminal 616. It should be noted that the output voltage of each electric core group is the same, so as to avoid damaging the electric core group when the electric core groups are connected in parallel.

When the external dc tool requires a high voltage output, the power socket is in the form of the second power socket 620. At this time, the dc tool requires two electric core sets to be connected in series to output the power supply voltage. For example, each battery pack can provide 18V voltage, and the two battery packs are connected in series, so that the whole battery pack outputs 36V voltage. The second power outlet 620 includes a first input terminal 621, a second input terminal 622, a third input terminal 623, a fourth input terminal 624, a first output terminal 625, a second output terminal 626, a third output terminal 627, and a fourth output terminal 628. Wherein, the first input terminal 621 and the first output terminal 625 of the second power jack 620 are connected; the second input terminal 622 and the second output terminal 626 are connected; the third input terminal 623 and the third output terminal 627 are connected; the fourth input terminal 624 and the fourth output terminal 628 are connected.

In use, in the second power socket 620, the first input terminal 621 is correspondingly connected to the first end 511 of the output component 530; the second input terminal 622 is correspondingly connected with the third end 521 of the output component 530; the third input terminal 623 is correspondingly connected with the fourth terminal 522 of the output assembly 530; the fourth input terminal 624 is correspondingly connected to the second end 512 of the output component 530. The second output terminal 626 and the fourth output terminal 628 of the second power outlet 620 are connected by a wire; the upper electric core group 510 and the lower electric core group 520 can be connected in series as shown in fig. 5. Eventually causing the second power outlet 620 to output 36V to the dc tool through the first output terminal 625 and the third output terminal 627.

The matching principle of the output current protection point of the battery pack is as follows:

when the battery pack is connected to different dc tools, the input terminal Pld of the load type detection module 120 is connected to different loads, and the load type detection module 120 generates different detection signals according to the connected loads at the input terminal Pld thereof and transmits the different detection signals to the control module 110. The control module 110 obtains an output current value required by the dc tool according to the detection signal, and obtains an overcurrent protection value, i.e., a protection point, according to the output current value. The control module 110 controls the electric core parameter detection module according to the output current value, so that the electric core parameter detection module controls the output current of the electric core group. Meanwhile, the cell parameter detecting module detects an electrical parameter of the cell pack, such as output current or voltage, and transmits the electrical parameter to the control module 110. The control module 110 judges whether the battery pack has over-current or under-voltage faults according to the electrical parameters, if so, the control module 110 generates a control signal to control the switch module to be switched off, and the passage of the electric core group is cut off, so that the electric core group is protected.

According to the battery pack provided by the embodiment of the invention, at least two voltage output branches are arranged, each voltage output branch comprises the electric core group, and when the battery pack is used, the output assembly 150 is used for controlling the series-parallel connection relation among the electric core groups, so that different voltage outputs are realized, and the applicability of the battery pack is improved. By setting the load type detection module 120, a detection signal is formed according to the access load and is transmitted to the control module 110, so that the control signal formed by the control module 110 includes information of the protection point. That is to say, this battery package can dispose the corresponding protection point of output current according to the load of external direct current instrument, and further the suitability of having improved the battery package. Therefore, the embodiment of the invention improves the universality of the battery pack, so that one battery pack can be applied to different direct current tools, the utilization rate of the battery pack is further improved, the cost is reduced, and the battery pack is convenient for a user to carry.

With continued reference to fig. 1, based on the above embodiments, optionally, the control module 110 is configured to determine a protection threshold according to the detection signal, determine whether the electrical parameter reaches the protection threshold, and generate a control signal to control the switch module to turn off when the electrical parameter reaches the protection threshold.

When the battery pack is connected to different dc tools, the detection signals transmitted by the load type detection module 120 to the control module 110 are different due to different supply voltages or loads of the different dc tools. The protection threshold determined by the control module 110 according to the detection signal is a critical value at which the battery pack can normally operate, and once the electrical parameter detected by the cell parameter detection module exceeds the critical value, it indicates that the battery pack has a fault, and power supply needs to be stopped to avoid further expansion of the fault. In this embodiment, the control module 110 controls the switch module to turn off to cut off the power supply line from the battery pack to the dc tool.

In this embodiment, the control module 110 determines the protection threshold according to the detection signal of the load type detection module 120, so that the protection threshold changes with the change of the external dc tool, and thus the obtained protection threshold is more accurate, thereby avoiding the false disconnection or the faulty operation caused by the fixed protection threshold.

With continued reference to fig. 1, the present embodiment further complements the determination of the protection threshold in addition to the above-described embodiments. Alternatively, when the output assembly 150 is electrically connected to a first type of dc tool, the load type detection module 120 outputs a first detection signal; when the output assembly 150 is electrically connected to the second type of dc tool, the load type detection module 120 outputs a second detection signal.

Further, when different dc tools of the first type have different loads, the first detection signal output by the load type detection module 120 is different, and thus the protection threshold is different. When different dc tools of the second type have different loads, the second detection signal output by the load type detection module 120 is different, and thus the protection threshold is different. For example, the load on the drill bit, which also requires a supply voltage of 18V, is 3.3k Ω and the load on the lawnmower is 10k Ω. The load of the drill bit is smaller than that of the grass trimmer, and correspondingly, the protection current of the drill bit is smaller than that of the grass trimmer.

In addition to the above embodiments, the present embodiment further supplements the structure of the switch module. There are many kinds of components and connection modes of the switch module, and some of them will be described below, but the invention is not limited thereto.

Fig. 6 is a schematic circuit structure diagram of a switch module according to an embodiment of the present invention. As shown in fig. 6, optionally, the switch module may include: the transistor comprises a first resistor R1, a second resistor R2, a third resistor R3, an optocoupler 210, a first triode T1 and a first MOS transistor M1.

The first end of the first resistor R1 is the control end of the switch module and is electrically connected with the control module; a second end of the first resistor R1 is electrically connected to a first input end of the optical coupler 210, a second input end of the optical coupler 210 is connected to a first ground signal GND1, a first output end of the optical coupler 210 is electrically connected to a base of the first triode T1 and a first end of the second resistor R2, respectively, a second pole of the first triode T1 is connected to the second ground signal CND2, and a first pole of the first triode T1 is electrically connected to a gate of the first MOS transistor M1 and a second end of the third resistor R3, respectively; the first pole of the first MOS transistor M1 is the second end of the switch module and is electrically connected with the output component; the second pole of the first MOS transistor M1 is the first end of the switch module and is electrically connected with the electric core group; the second end of the second resistor R2 and the first end of the third resistor R3 are both connected to the first voltage V1.

Wherein, the first end of the first resistor R1 is electrically connected with the control module. The operating principle of the switching module is, for example, as follows:

when the control module outputs a high level, the optocoupler 210 is turned on, so that the first transistor T1 is turned off, and further, under the action of the first voltage V1, the first MOS transistor M1 is turned on, and the voltage output branch outputs a normal voltage.

When the control module outputs a low level, the optocoupler 210 is not turned on, and under the action of the first voltage V1, the first transistor T1 is turned on, so that the gate of the first MOS transistor M1 is grounded, the first MOS transistor M1 is turned off, and the connection between the second connection terminal and the cell group in the voltage output branch is cut off.

In the embodiment, the optical coupler is arranged, so that electrical isolation is realized, and high reliability of control of the switch module is ensured.

Fig. 7 is a schematic circuit diagram of another switch module according to an embodiment of the present invention. As shown in fig. 7, further, when the switch module includes the first resistor R1, the second resistor R2, the third resistor R3, the optocoupler 210, the first transistor T1, and the first MOS transistor M1, the switch module further includes a third MOS transistor M3, an eighth resistor R8, and a first zener diode D1.

The grid electrode of the third MOS tube M3 is electrically connected with the grid electrode of the first MOS tube M1; the first pole of the third MOS transistor M3 is electrically connected to the first pole of the first MOS transistor M1 and serves as the second end of the switch module; the second pole of the third MOS transistor M3 is electrically connected to the second pole of the first MOS transistor M1 and serves as the first terminal of the switch module; the first end of the eighth resistor R8 and the second pole of the first zener diode D1 are both electrically connected to the second end of the third resistor R3, and the second end of the eighth resistor R8 and the first pole of the first zener diode D1 are both connected to the second ground signal GND 2.

The eighth resistor R8 and the first zener diode D1 function as an overcurrent and overvoltage protection, and can protect the first MOS transistor M1 and the third MOS transistor M3 from being damaged when the first voltage V1 is abnormal. The third MOS tube M3 is additionally arranged, when one of the first MOS tube M1 and the third MOS tube M3 is abnormal, the other MOS tube can also ensure the normal work of the switch module, and the stability of the battery pack is improved.

Fig. 8 is a schematic circuit diagram of another switch module according to an embodiment of the present invention. As shown in fig. 8, optionally, the switch module may include: the circuit comprises a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a second triode T2, a third triode T3 and a second MOS tube M2.

A first end of the fourth resistor R4 is a control end of the switch module and is electrically connected with the control module; a second end of the fourth resistor R4 is electrically connected to a first end of the fifth resistor R5 and a base of the second transistor T2, respectively, a second end of the fifth resistor R5, a second pole of the second transistor T2 and a second pole of the third transistor T3 are all connected to the third ground signal CND3, a first pole of the second transistor T2 is electrically connected to a base of the third transistor T3 and a first end of the sixth resistor R6, respectively, and a first pole of the third transistor T3 is electrically connected to a gate of the second MOS transistor M2 and a second end of the seventh resistor R7, respectively; the first pole of the second MOS transistor M2 is the second end of the switch module and is electrically connected to the output component; the second pole of the second MOS transistor M2 is the first end of the switch module and is electrically connected with the electric core group; the second end of the sixth resistor R6 and the first end of the seventh resistor R7 are both connected to a second voltage V2.

The first end of the fourth resistor R4 is electrically connected with the control module. Alternatively, the third ground signal CND3 and the second ground signal may be the same signal. The second voltage V2 and the first voltage can be the same voltage and are both provided by the electric core group. The operating principle of the switching module is, for example, as follows:

when the control module outputs a high level, the second triode T2 is turned on, so that the base of the third triode T3 is connected to a low level, the third triode T3 is turned off, the second MOS transistor M2 is turned on under the action of the second voltage V2, and the voltage output branch circuit outputs a normal voltage.

When the control module outputs a low level, the second triode T2 is turned off, and the third triode T3 is turned on under the action of the second voltage V2, so that the gate of the second MOS transistor M2 is connected to the low level, the second MOS transistor M2 is turned off, and the connection between the second connection terminal and the electric core group in the voltage output branch circuit is cut off.

Fig. 9 is a schematic circuit diagram of another switch module according to an embodiment of the present invention. As shown in fig. 9, optionally, when the switch module includes the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, the second transistor T2, the third transistor T3, and the second MOS transistor M2, the switch module further includes a fourth MOS transistor M4, a ninth resistor R9, and a second zener diode D2;

the gate of the fourth MOS transistor M4 is electrically connected with the gate of the second MOS transistor M2; a first pole of the fourth MOS transistor M4 is electrically connected to the first pole of the second MOS transistor M2 and serves as a second end of the switch module; the second pole of the fourth MOS transistor M4 is electrically connected to the second pole of the second MOS transistor M2 and serves as the first terminal of the switch module; the first end of the ninth resistor R9 and the second pole of the second zener diode D2 are both electrically connected to the second end of the seventh resistor R7, and the second end of the ninth resistor R9 and the first pole of the second zener diode D2 are both connected to the third ground signal GND 3.

The ninth resistor R9 and the second zener diode D2 function as overcurrent and overvoltage protection, and can protect the second MOS transistor M2 and the fourth MOS transistor M4 from being damaged when the second voltage V2 is abnormal. The fourth MOS tube M4 is additionally arranged, when one of the second MOS tube M2 and the fourth MOS tube M4 is abnormal, the other MOS tube can also ensure the normal work of the switch module, and the stability of the battery pack is improved.

In addition to the above embodiments, the present embodiment further supplements the structure of the load type detection module. Fig. 10 is a schematic circuit diagram of a load type detection module according to an embodiment of the present invention. As shown in fig. 10, the load type detection module includes: a tenth resistor R10; a first end of the tenth resistor R10 is used for inputting the voltage signal Vin; a second terminal of the tenth resistor R10 serves as an input terminal and an output terminal of the load type detection module.

The voltage signal Vin can be provided by the control module, and can also be provided by the electric core group. When the voltage signal Vin is provided by the electric core group, it is necessary to select a proper resistance value of the tenth resistor R10 so that the output voltage does not exceed the voltage provided by the control module. When the battery pack is connected with different direct current tools, the input end of the load type detection module is connected with different loads, correspondingly, the partial pressure of the different loads is different, so that the voltage output by the load type detection module is different, namely, the output detection signals are different.

Further, the load type detection module further includes: an eleventh resistor R11; a first end of the eleventh resistor R11 is electrically connected with a second end of the tenth resistor R10, and is used as an input end of the load type detection module and is electrically connected with the direct current tool; and a second end of the eleventh resistor R11 is used as an output end of the load type detection module and is electrically connected with the control module.

The eleventh resistor R11 can be used as a current limiting resistor to prevent the current input to the control module from being too large, and prevent the control module from being damaged.

On the basis of the foregoing embodiments, this embodiment further supplements the structure of the cell parameter detection module. Fig. 11 is a schematic circuit structure diagram of a cell parameter detection module according to an embodiment of the present invention. As shown in fig. 11, the cell parameter detection module 320 includes: a cell management chip 321 and a cell current detection unit 322;

the battery cell management chip 321 is electrically connected with the battery cell group 310 and the control module 110; a first end and a second end of the cell current detection unit 322 are both electrically connected to the cell management chip 321; the cell current detection unit 322 is used for detecting the current of the cell group 310; the electrical parameter includes the current of the electric core group 310.

The electrical parameters collected by the cell management chip 321 include current data of the cell group 310 detected by the cell current detection unit 322. The cell management chip 321 transmits the electrical parameters to the control module 110. The control module 110 determines whether the cell group 310 operates in a normal state according to the electrical parameters. If the cell group 310 works in an overcurrent state, the control module 110 controls the switch module to be turned off to protect the cell group 310. In addition to collecting electrical parameters, the cell management chip 321 may also be used to control the output current of the cell group 310.

On the basis of the foregoing embodiments, the present embodiment specifically describes the structure of the battery cell parameter detection module. Fig. 12 is a schematic circuit structure diagram of another battery cell parameter detection module according to an embodiment of the present invention. As shown in fig. 12, the cell current detection unit 322 includes: a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a first capacitor C1, a second capacitor C2 and a third capacitor C3.

A first end of the twelfth resistor R12 is electrically connected with a first end of the thirteenth resistor R13 and a second end of the fourteenth resistor R14, respectively; a second end of the twelfth resistor R12 is electrically connected with a second end of the thirteenth resistor R13 and a second end of the fifteenth resistor R15, respectively; a first end of the fourteenth resistor R14 is electrically connected to a first end of the first capacitor C1 and a first end of the third capacitor C3, respectively, and serves as a first end of the cell current detection unit 322; a first end of the fifteenth resistor R15 is electrically connected to the second end of the second capacitor C2 and the second end of the third capacitor C3, respectively, and serves as a second end of the cell current detection unit 322; the second terminal of the first capacitor C1 and the first terminal of the second capacitor C2 are both connected to the fourth ground signal GND 4.

Alternatively, the electric core group 310 may be connected with the switch module 330 through a twelfth resistor R12. The fourth ground signal GND4 may be the same ground signal as the third ground signal and the second ground signal. The first end of the electric core group 310 is a positive output end P +, and the second end of the switch module 330 is a negative output end P-. The cell management chip 321 is electrically connected to the control module 110 through a 6 pin.

In the cell current detection unit 322, the thirteenth resistor R13 and the twelfth resistor R12 are arranged in parallel to serve as current detection resistors, so that resistor type selection during actual application is facilitated, and a more-range current detection resistor value is facilitated. The fourteenth resistor R14 and the fifteenth resistor R15 are used for limiting current, and prevent the cell management chip 321 from being burnt by current passing through the 4 pins and the 5 pins of the cell management chip 321. The first capacitor C1, the second capacitor C2 and the third capacitor C3 are used as filter capacitors, so that the cell management chip 321 can detect the current of the cell group 310 more stably and accurately.

With continued reference to fig. 12, optionally, the battery pack 310 includes at least two battery cells connected in series (here, taking two battery cells as an example, a first battery cell B1 and a second battery cell B2). The positive electrode of the battery cell is electrically connected to the voltage detection terminal of the battery cell management chip 321.

The positive electrode of the battery cell is electrically connected to the voltage detection terminal of the battery cell management chip 321, so that the battery cell management chip 321 can collect the output voltage of each battery cell (that is, the output electrical parameter includes the voltage information of each battery cell) to monitor the health status of each battery cell at any time.

Further, the cell management chip 321 and the cell group 310 may be connected through a voltage detection unit 323. The voltage detection unit 323 includes the same number of voltage detection resistors and filter capacitors as the number of cells. Taking fig. 12 as an example, the positive electrode of the first cell B1 is electrically connected to the first end of the sixteenth resistor R16, and the second end of the sixteenth resistor R16 is electrically connected to the 1 pin of the cell management chip 321 and the first end of the fourth capacitor C4, respectively; the anode of the second cell B2 is electrically connected to the first end of the seventeenth resistor R17, and the second end of the seventeenth resistor R17 is electrically connected to the 2 pin of the cell management chip 321 and the first end of the fifth capacitor C5, respectively; the second end of the fourth capacitor C4, the second end of the fifth capacitor C5, and the ground pin 3 of the cell management chip 321 are both connected to a fourth ground signal GND 4.

In this embodiment, the positive electrode of each cell is connected to the cell management chip through a voltage detection resistor, and a filter capacitor is introduced between each voltage detection resistor and the cell management chip, so that the cell voltage acquired by the cell management chip is more stable and accurate.

On the basis of the above embodiments, optionally, the battery pack may further include a power-on self-locking module and a power-on triggering module to ensure that the circuit operates normally; the battery can also comprise a charging identification module to ensure the safety of battery cell charging; the temperature detection module can be further included to ensure the safety of the battery pack during charging and discharging, prevent the battery pack from being damaged or even exploded due to overheating, and ensure the safe use of the electric appliance; an external communication module may be further included to facilitate monitoring of status information of the battery pack.

The embodiment of the invention also provides a direct current tool. Fig. 13 is a schematic structural diagram of a dc tool according to an embodiment of the present invention. As shown IN fig. 13, the dc tool 420 includes an identification resistor Ri, a load type output terminal Lout, and a power supply input terminal IN, wherein the identification resistor Ri is an adjustable resistor.

The identification resistor Ri is electrically connected to a load type output terminal Lout, and the load type output terminal Lout is used for being electrically connected to a load type detection module in the battery pack provided by any embodiment of the present invention. The power input IN may be an input to a power socket IN the dc tool 420 for electrical connection with an output component of the battery pack.

The direct current tool 420 provided by the embodiment of the invention is provided with the identification resistor Ri, when the direct current tool 420 is connected to the battery pack, the information of the identification resistor Ri is identified by the battery pack through the load type detection module in the battery pack, so that the battery pack can identify the load of the direct current tool 420, and the output current and the corresponding protection point are configured according to the load of the direct current tool 420, thereby improving the applicability of the battery pack.

Preferably, the dc tool 420 may further be equipped with different input components, which may be plugged into battery packs with different output voltages, so as to convert the output voltages of the battery packs into the supply voltages required by the dc tool 420 itself, so as to improve the applicability of the dc tool 420.

The embodiment of the invention also provides a direct current tool component. Fig. 14 is a schematic structural diagram of a dc tool assembly according to an embodiment of the present invention. As shown in fig. 14, the dc tool assembly comprising the battery pack 410 according to any embodiment of the present invention and the dc tool 420 according to any embodiment of the present invention has corresponding advantages.

The load type output terminal Lout of the dc tool 420 is electrically connected to the load type detection module 412 of the battery pack 410, and the power supply input terminal IN of the dc tool 420 is electrically connected to the output component 411 of the battery pack 410.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A battery pack for powering a dc tool, the battery pack comprising:

an output assembly removably electrically connected with the DC tool;

the electric core group;

the battery pack further includes:

2. The battery pack according to claim 1, wherein:

the control module is configured to determine a protection threshold according to the detection signal, determine whether the electrical parameter reaches the protection threshold, and generate a control signal to control the switch module to turn off when the electrical parameter reaches the protection threshold.

3. The battery pack according to claim 2, wherein:

when the output assembly is electrically connected with the first type of direct current tool, the load type detection module outputs a first detection signal;

4. The battery pack of claim 1, wherein the switch module comprises: the circuit comprises a first resistor, a second resistor, a third resistor, an optical coupler, a first triode and a first MOS (metal oxide semiconductor) tube;

5. The battery pack of claim 1, wherein the load type detection module comprises: a tenth resistor and an eleventh resistor;

6. The battery pack of claim 1, wherein the cell parameter detection module comprises: the battery cell management chip comprises a battery cell management chip and a battery cell current detection unit;

7. The battery pack of claim 6, wherein the cell current detection unit comprises: a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a first capacitor, a second capacitor and a third capacitor;

8. The battery pack of claim 6, wherein the battery pack comprises at least two cells connected in series;

9. A direct current tool is characterized by comprising an identification resistor, a load type output end and a power supply input end;

the identification resistor is electrically connected with the load type output end, the load type output end is used for being electrically connected with the load type detection module in the battery pack according to any one of claims 1-8, and the power supply input end is used for being electrically connected with the output assembly of the battery pack.

10. A dc tool assembly comprising a battery pack according to any of claims 1 to 8 and a dc tool according to claim 9;