KR101746762B1 - Battery protection circuit module and battery pack including the same - Google Patents

Abstract

A battery protection circuit module according to one aspect of the present invention includes a first positive electrode terminal and a first negative electrode terminal electrically connected to electrode terminals of a battery bare cell, a second positive electrode terminal electrically connected to the charger or the electronic device, A first negative terminal, a second negative terminal, a drain terminal, a source terminal, a gate terminal, and a well terminal, the drain terminal being electrically connected to the first negative terminal and the source terminal being electrically connected to the second negative terminal A field effect transistor connected between one node between the first negative terminal and the drain terminal and another node between the second negative terminal and the source terminal and receiving a bias control signal through the input terminal, An inverter element for outputting a bias voltage through an output terminal connected to the one node, And a bias control signal output terminal connected to an input terminal of the inverter element for outputting the bias control signal; and a protection control signal output terminal connected to the other node, Circuit elements.

Description

A battery protection circuit module, and a battery pack including the battery protection circuit module.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery for an electronic device, and more particularly, to a battery protection circuit module for protecting a battery cell and a battery pack including the battery protection circuit module.

Generally, batteries are used in electronic devices such as mobile phones and PDAs. Lithium-ion batteries are the most widely used batteries in portable handsets, and they have overcharging and over-currents, and when the temperature rises due to the heat generation, the performance deteriorates as well as the risk of explosion. Therefore, in order to prevent such performance deterioration, there is an increasing need to provide a battery protection circuit device that cuts off the operation of the battery.

1. Published Patent Application No. 10-2007-0044544 (Apr. 30, 2007) 2. Registration patent publication 10-0791551 (December 27, 2007)

Conventional battery protection circuit devices use two field effect transistors as switching elements to control charging and discharging, but it is difficult to reduce the performance degradation and the volume due to the increase of the operating resistance.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a battery protection circuit module and a battery pack using a single field-effect transistor for solving various problems including the above-described problems. However, these problems are exemplary and do not limit the scope of the present invention.

A battery protection circuit module according to one aspect of the present invention includes a first positive electrode terminal and a first negative electrode terminal electrically connected to electrode terminals of a battery bare cell, a second positive electrode terminal electrically connected to the charger or the electronic device, A first negative terminal, a second negative terminal, a drain terminal, a source terminal, a gate terminal, and a well terminal, the drain terminal being electrically connected to the first negative terminal and the source terminal being electrically connected to the second negative terminal A field effect transistor connected between one node between the first negative terminal and the drain terminal and another node between the second negative terminal and the source terminal and receiving a bias control signal through the input terminal, An inverter element for outputting a bias voltage through an output terminal connected to the one node, A charge control signal output terminal connected to the gate terminal and a bias control signal output terminal connected to an input terminal of the inverter element for outputting the bias control signal, A gate terminal to control the switching of the single field effect transistor and control the well terminal through the inverter element to control the operation of the parasitic diodes of the single field effect transistor to control the charging and discharging of the battery bare cell. And may include integrated circuit devices.

In the battery protection circuit module, the protection integrated circuit element turns off the single field effect transistor using the charge / discharge control signal output terminal to prevent overcharging during overcharge detection, and the bias control signal output terminal So that the well terminal can be connected to the sensing terminal through the other node.

The protection integrated circuit device turns off the single field effect transistor using the charge / discharge control signal output terminal to shut off overdischarge during overdischarge detection, and the bias control signal output Terminal may be connected to the ground terminal through the one node.

In the battery protection circuit module, the protection integrated circuit device may detect the connection of the charger or the load when the overcharge or over-discharge is cut off and then the charge or discharge is returned to the protection integrated circuit device to turn on the single field effect transistor.

In the battery protection circuit module, the single field effect transistor and the inverter element may be provided in separate chips or may be provided in a single chip.

The battery protection circuit module according to claim 1, wherein the inverter element includes an n-type field effect transistor and a p-type field effect transistor connected in series to each other, and the bias control signal is a voltage applied to the n-type field effect transistor and the p- And a high or low logic signal for controlling turn-on and turn-off.

According to another aspect of the present invention, there is provided a battery pack comprising: a battery bare cell; And a battery protection circuit module connected to the battery bare cell. The battery protection circuit module includes a first positive electrode terminal and a first negative electrode terminal electrically connected to the electrode terminals of the battery bare cell, a second positive electrode terminal and a second negative electrode terminal electrically connected to the charger or the electronic device, A single field effect transistor including a drain terminal, a source terminal, a gate terminal and a well terminal, the drain terminal being electrically connected to the first negative terminal, and the source terminal being electrically connected to the second negative terminal, And an output terminal connected to one of the node between the first negative terminal and the drain terminal and another node between the second negative terminal and the source terminal and receiving a bias control signal through the input terminal, An inverter element for outputting a bias voltage through the node, a reference terminal connected to the one node, A charging control signal output terminal connected to the gate terminal and a bias control signal output terminal connected to an input terminal of the inverter element for outputting the bias control signal, And a protection integrated circuit device for controlling switching of the single field effect transistor and controlling the well terminal through the inverter element to control the operation of the parasitic diodes of the single field effect transistor to control charging and discharging of the battery bare cell .

According to the embodiments of the present invention as described above, it is possible to provide a battery protection circuit capable of reducing the operation resistance and improving the performance and being compact. Of course, the scope of the present invention is not limited by these effects.

1 is a schematic circuit diagram showing a battery protection circuit module according to an embodiment of the present invention.
2 is a schematic circuit diagram showing a configuration of a battery protection circuit module according to another embodiment of the present invention.
3 is a schematic perspective view showing a battery protection circuit module according to embodiments of the present invention.
4 is a perspective view illustrating a battery pack according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, It is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the concept of the invention to those skilled in the art. In the drawings, the thickness and size of each layer are exaggerated for convenience and clarity of explanation.

In describing embodiments of the present invention, the same reference numerals can be used to describe the concept of a circuit from the viewpoint of a battery protection circuit, but the concept of a device or a circuit part can be described from the viewpoint of a battery protection circuit package.

In describing embodiments of the present invention, an integrated circuit (IC) may mean an electronic component in which many devices are integrated into one chip to process a specific complicated function.

1 is a schematic circuit diagram showing a battery protection circuit module according to an embodiment of the present invention.

1, a battery protection circuit module according to this embodiment includes a first positive terminal 102 and a first negative terminal 104 electrically connected to the electrode terminals of the battery bare cell Bc, And a second anode terminal 106 and a second anode terminal 108 electrically connected to the electronic device. For example, the first positive terminal 102 is an internal positive terminal B + connected to the positive terminal of the battery bare cell Bc in the battery pack and the first negative terminal 104 is connected to the positive terminal of the battery bare cell Bc. (B +) connected to the anode of the electronic device, and the second anode terminal 106 is an external cathode terminal (P +) connected to the charger of the battery pack or the anode of the electronic device and the second anode terminal Or an external negative electrode terminal (P-) connected to the negative electrode of the electronic device.

Further, although not shown in the drawings, the battery protection circuit module according to some embodiments of the present invention may further include a separate additional external connection terminal.

The battery protection circuit module includes a single field effect transistor (FET) 102 connected between at least one of the first positive terminal 102 or the first negative terminal 104 and at least one of the second positive terminal 106 and the second negative terminal 108. [ And a protection integrated circuit device (P-IC) 118 for controlling the single field effect transistor 112.

For example, the single field effect transistor 112 may include a drain terminal D, a source terminal S, a gate terminal G and a well terminal Bin, 2 cathode terminal 108. In the present embodiment, For example, the drain terminal D may be electrically connected to the first negative terminal 104, and the source terminal S may be electrically connected to the second negative terminal 108. [ However, since the drain terminal D and the source terminal S are not distinguished from each other in the single field effect transistor 112, the two terminals may be mutually called.

The single field effect transistor 112 and the protection integrated circuit element 118 for controlling the single field effect transistor 112 can constitute a protection circuit unit. Such a protection circuit unit can detect over discharge, overcharge, and / or overcurrent of the battery, thereby preventing charging / discharging or operation of the battery bare cell. Specifically, the protection integrated circuit device 118 may control the single field effect transistor 112 to control overcharge and / or overdischarge of the battery bare cell BC.

The single field effect transistor 112 may be, for example, an N-type MOSFET (NMOSFET). And a pair of parasitic diodes PD1 and PD2 connected to each other in the opposite directions about a node n4 connected to the well terminal W. [ For example, the parasitic diode PD1 may be connected such that the direction of the drain electrode D from the node n4 is positive and the parasitic diode PD2 is connected so that the direction of the source electrode S from the node n4 is positive have.

The protection integrated circuit device 118 may include control logic to control a single field effect transistor 112 therein. For example, the control logic may include a reference voltage setting unit, a comparison unit for comparing the reference voltage with the charge / discharge voltage, an overcurrent detection unit, and a charge / discharge detection unit.

The charging and discharging state judgment criterion can be changed to the specification (SPEC) required by the user, and the charge / discharge state is judged by recognizing the voltage difference of each terminal of the protection integrated circuit element 118 according to the predetermined criterion. For example, the protection integrated circuit device 118 includes a reference terminal Vss, a power supply terminal Vdd, a sensing terminal V-, a charge / discharge control signal output terminal CDout, And a signal output terminal (Bout).

The protection integrated circuit element 118 may be connected to the nodes n1, n2, and n4 via at least one passive element. For example, the power supply terminal vdd is connected to the node n1 between the first positive terminal 102 and the second positive terminal 106 via the resistor R1, and the reference terminal Vss is connected to the first negative terminal (N2) between the source terminal (104) and the drain terminal (D). A capacitor C1 may be interposed between the reference terminal Vss and the power supply terminal Vdd between the node n1 and the node n2 to prevent a short circuit between the two nodes n1 and n3. The sensing terminal V- can be connected to the node n3 through the resistor R2.

According to this configuration, the protection integrated circuit device 118 can apply the charging voltage or the discharging voltage through the power supply terminal Vdd with reference to the voltage of the reference terminal Vss, Charge / discharge and overcurrent condition can be detected. The charge and discharge control signal output terminal CDout is connected to the gate terminal G of the single field effect transistor 112 to control on-off of the single field effect transistor 112 upon charging and / .

The charging current flows from the second positive terminal 106 to the first positive terminal 102 and from the first negative terminal 104 to the second negative terminal 108 when the battery is charged. The discharging current flows from the first positive terminal 102 to the second positive terminal 106 and from the second negative terminal 108 to the first negative terminal 104 when the battery is discharged.

The protection integrated circuit device 118 outputs a low signal through the charge / discharge control signal output terminal CDout to turn off the single field effect transistor 112 when the overcurrent or overdischarge state is detected during battery discharge , And when the battery is being charged, it may operate to output a low signal through the charge / discharge control signal output terminal CDout to turn off the single field effect transistor 112 when an overcurrent or overcharge state is detected. As a result, the circuit between the first negative terminal 104 and the second negative terminal 108 is cut off, thereby overcharging, overdischarging, and / or overcurrent of the battery can be blocked.

Further, the protection integrated circuit device 118 applies a voltage to the well terminal W of the single field effect transistor 112 through the bias control signal output terminal Bout in addition to the charge / discharge control signal output terminal CDout So that the operation or the electric field state of the parasitic diodes PD1 and PD2 can be controlled.

For example, in the inverter device 120, the first terminal DBin is connected to the node n2 between the first negative terminal 104 and the drain terminal D, and the second terminal SBin is connected to the second negative terminal And a node n3 between the terminal 108 and the source terminal S. [ The inverter device 120 includes an input terminal BCin and an output terminal BCout and receives a bias control signal through an input terminal BCin to receive a bias control signal via an output terminal BCout connected to the well terminal W. [ Voltage can be output. For example, the first terminal DBin may be a drain bias input terminal, and the second terminal SBin may be a source bias input terminal.

For example, the inverter device 120 may include a first field effect transistor 122 and a second field effect transistor 124 connected in series with each other. For example, the first field effect transistor 122 may be a p-type field effect transistor (PMOSFET) and the second field effect transistor 124 may be an n-type field effect transistor (NMOSFET). In this case, when a logic high signal is input to the input terminal BCin, the first field effect transistor 122 is turned off, the second field effect transistor 124 is turned on, the voltage of the sensing terminal V- is applied to the well terminal W because the sensing terminal V- is connected to the sensing terminal V- through the sensing terminal V3. Conversely, when a logic low signal is input to the input terminal BCin, the first field effect transistor 122 is turned on and the second field effect transistor 124 is turned off so that the output terminal BCout is connected to the node n2 to the reference terminal Vss so that the voltage of the reference terminal Vss is applied to the well terminal W. [ Meanwhile, in a modified example of this embodiment, the first field effect transistor 122 is an n-type field effect transistor (NMOSFET) and the second field effect transistor 124 is a p-type field effect transistor (PMOSFET) have.

The resistor R1 and the capacitor C1 serve to stabilize the fluctuation of the supply power source of the protection integrated circuit element 118. [ When the resistance value of the resistor R1 is increased, the detection voltage becomes higher due to the current penetrated into the protection integrated circuit element 118 at the time of voltage detection. Therefore, the resistance value of the resistor R1 is set to a predetermined value, Can be set. Also, for stable operation, the capacitance value of the capacitor C1 may be appropriately adjusted, and may have an appropriate value of, for example, 0.01 mu F or more.

The resistor R1 and the resistor R2 become a current limiting resistor when the high voltage charger or charger that exceeds the absolute maximum rating of the protection integrated circuit element 118 is connected upside down. The sum of the resistance value in the resistor R1 and the resistance value in the resistor R2 may be set to be larger than 1 K? Since the resistor R1 and the resistor R2 may cause power consumption. If the resistance value of the resistor R2 is too large, a return may not occur after the overcharge cutoff, so that the resistance value of the resistor R2 may be set to a value of 10K or less.

The capacitor C1 does not significantly affect the characteristics of the battery protection circuit product, but is added for user's request or stability. The capacitor C1 is for stabilizing the system by improving the resistance to voltage fluctuation and external noise.

Alternatively, although not shown in the drawing, a structure in which a resistor and a varistor are connected in parallel may be added for ESD (Electrostatic Discharge) and surge protection. The varistor device has a low resistance when overvoltage is generated. When the overvoltage is generated, the resistance is lowered to minimize circuit damage due to overvoltage. The number or arrangement of the passive elements in the above-described protective circuit unit can be appropriately modified in accordance with the additional function.

Hereinafter, the operation of the battery protection circuit module will be described in more detail.

The protection integrated circuit device 118 controls the gate terminal G to control the switching of the single field effect transistor 112 and control the well terminal W through the inverter element 120 to generate the parasitic diodes PD1 and PD2 To control the charging and discharging of the battery bare cell Bc.

The protection integrated circuit device 118 turns off the single field effect transistor 112 by using the charge / discharge control signal output terminal CDout in order to block the overcharging during overcharge detection during charging or during charging overcurrent detection, The well terminal W can be connected to the sensing terminal V- through the node n3 using the signal output terminal Bout. For example, in this embodiment, the charge / discharge control signal may be a logic low signal and the bias control signal may be a logic high signal. In this case, the parasitic diode PD2 which becomes the forward direction at the time of charging becomes neutralized and the parasitic diode PD1 which becomes the reverse direction becomes a constant withstand voltage, so that the charging current in the direction of the source S from the drain D can be cut off. As a result, the charging current can be cut off in the entire circuit.

Upon detection of a set potential change of the power supply terminal (Vdd), the sensing terminal (V-) and / or the reference terminal (Vss) to recognize the charger removal or the load connection, the protection integrated circuit element (118) The effect transistor 112 may be turned on and the well terminal W may be connected to the reference terminal Vss via the node n2 to control the charging to proceed.

The protection integrated circuit device 118 turns off the single field effect transistor 112 using the charge / discharge control signal output terminal CDout to cut off the over discharge during the over discharge detection or the discharge over current detection during the discharge, The well terminal W can be connected to the reference terminal Vss through the node n2 by using the control signal output terminal Bout. For example, in this embodiment, the charge / discharge control signal may be a logic low signal, and the bias control signal may also be a logic low signal. In this case, the parasitic diode PD1 which is in the forward direction at the time of discharging is disabled and the parasitic diode PD2 which becomes the reverse direction becomes the constant withstand voltage, the discharge current in the direction of the source D from the drain S can be cut off. As a result, the discharge current can be cut off in the entire circuit.

The protection integrated circuit device 118 recognizes the charger connection or the load removal by detecting the change in the set potential of the power supply terminal Vdd, the sensing terminal V- and / or the reference terminal Vss, The effect transistor 112 may be turned on and the well terminal W may be continuously connected to the reference terminal Vss to control the charging to proceed.

According to the above-described battery protection circuit module, by using a single field effect transistor 112 rather than a conventional dual field effect transistor, the resistance can be lowered to increase the overall operation speed, and additionally, volume reduction can be expected.

Since the above-described protection circuit unit can be implemented as a semiconductor chip, it can be fabricated minutely by micro or nanometer using a silicon process technology. For example, both the protection integrated circuit device 118 and the single field effect transistor 112 can be fabricated as semiconductor chips as well as passive components such as resistors R1 and R2, capacitors C1 and C2, Can also be manufactured in chip form. Such a chip structure can be easily mounted on a substrate using surface mounting technology (SMT).

2 is a schematic circuit diagram showing a configuration of a battery protection circuit module according to another embodiment of the present invention. This embodiment shows only a configuration partially modified in the battery protection circuit module of Fig. 1, and redundant description is omitted in both embodiments.

In FIG. 1, the single field effect transistor 112 and the inverter element 120 are shown in FIG. 2, assuming that the single field effect transistor 112 and the inverter element 120 are provided in a separate chip form. The circuit is shown assuming that it is provided in one chip, that is, in a one-chip form. Such a one-chip form can be realized through a semiconductor integration process on a single substrate.

3 is a perspective view schematically showing a battery protection circuit module according to an embodiment of the present invention.

Referring to FIG. 3, the above-described battery protection circuit module may be mounted on the substrate 50 and implemented in a packaging form. For example, the substrate 50 may comprise a printed circuit board or a leadframe. The protection circuit unit constituting the battery protection circuit module can be sealed in one package by using the molding material 55. [

In a modified example of this embodiment, the protection circuit units described above may be mounted on the substrate 50 in the form of a chip scale package (CSP), respectively, to reduce their volume.

In another variation of this embodiment, the field effect transistor 114, the second field effect transistor 112 and the protection integrated circuit element 118 may be a stacked package structure or a package on package (POP) Structure.

4 is a schematic exploded perspective view showing a battery pack according to an embodiment of the present invention.

Referring to FIG. 4, the battery protection circuit module 300 is inserted between the upper surface of the battery bare cell and the upper case 500 built in the battery can 400 to form the battery pack 600. The upper case 500 is formed with a through hole 550 in a portion corresponding to the external connection terminals P + and P- so that the external connection terminals P + and P- can be exposed by plastic and / or metal.

The battery bare cell includes an electrode assembly and a cap assembly. The electrode assembly includes a positive electrode plate formed by applying a positive electrode active material to a positive electrode collector, a negative electrode plate formed by applying a negative electrode active material to a negative electrode collector, and a negative electrode plate interposed between the positive electrode plate and the negative electrode plate, As shown in Fig. A positive electrode tab attached to the positive electrode plate and a negative electrode tab attached to the negative electrode plate are drawn out from the electrode assembly.

The cap assembly includes an anode terminal 410, a gasket 420, a cap plate 430, and the like. The cap plate 430 may serve as a positive electrode terminal. The cathode terminal 410 may be referred to as a cathode cell or an electrode cell. The gasket 420 may be formed of an insulating material to insulate the cathode terminal 410 from the cap plate 430. Therefore, the electrode terminal of the battery bare cell may include the negative terminal 410 and the cap plate 430.

The electrode terminal of the battery bare cell includes a plate 430 of a first polarity (e.g., an anode) and an electrode cell 410 of a second polarity (e.g., cathode) disposed centrally within the plate 430 The first internal connection terminal lead B + is connected to the plate 430 of the first polarity (for example, an anode) to be electrically connected, and the second internal connection terminal lead B- is electrically connected to the second And can be electrically connected to the electrode cell 410 of the polarity (for example, the cathode).

In some embodiments, the length of the leadframe 50 is greater than the length from one end of the plate 430 of the first polarity (e.g., an anode) to the electrode cell 410 of the second polarity (e. G., The cathode) (L / 2). In this case, since the battery protection circuit package module 300 is mounted using only one side region of the upper portion with respect to the electrode cell 410 of the second polarity (for example, the cathode), it is possible to realize the miniaturization or high capacity of the battery have. For example, it is possible to contribute to miniaturization of an application product having such a battery by further forming a cell on the other side of the electrode cell 410 to increase the capacity of the battery or disposing a chip or the like having another additional function.

In other embodiments, the length of the lead frame 50 may extend beyond one side of the battery bare cell, in which case the electrode cell 410 of the second polarity (e. G., The cathode) The battery protection circuit package module 300 may be mounted using both side regions.

While the present invention has been described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

112: single field effect transistor
118: Protection Integrated Circuit Device
120: inverter device

Claims (8)

delete A first positive terminal and a first negative terminal electrically connected to the electrode terminals of the battery bare cell;
A second positive electrode terminal and a second negative electrode terminal electrically connected to the charger or the electronic device;
A single field effect transistor including a drain terminal, a source terminal, a gate terminal and a well terminal, the drain terminal being electrically connected to the first negative terminal, and the source terminal being electrically connected to the second negative terminal;
And an output terminal connected to one of the node between the first negative terminal and the drain terminal and another node between the second negative terminal and the source terminal and receiving a bias control signal through the input terminal, An inverter element for outputting a bias voltage through the inverter; And
A bias terminal connected to said one node, a sense terminal connected to said another node, a charge / discharge control signal output terminal connected to said gate terminal, and a bias control connected to an input terminal of said inverter element for outputting said bias control signal. Controlling the operation of the parasitic diodes of the single field effect transistor by controlling the switching of the single field effect transistor by controlling the gate terminal and controlling the well terminal through the inverter element, And a protection integrated circuit element for controlling charging and discharging of the bare cell,
The protection integrated circuit device turns off the single field effect transistor using the charge / discharge control signal output terminal to block overcharging during overcharge detection, and uses the bias control signal output terminal to switch the well terminal to the other To the sense terminal through a node. The protection integrated circuit device according to claim 2, wherein the protection integrated circuit element turns off the single field effect transistor using the charge / discharge control signal output terminal to shut off overdischarge during overdischarge detection, To connect the well terminal to the ground terminal via the one node. The protection integrated circuit device according to claim 2 or 3, wherein the protection integrated circuit device detects a connection of a charger or a load when the overload protection circuit is overcharged or over-discharged, and then turns on the single field effect transistor module. 5. The battery protection circuit module of claim 4, wherein the single field effect transistor and the inverter element are provided in separate chips. 5. The battery protection circuit module of claim 4, wherein the single field effect transistor and the inverter element are provided in a single chip. The inverter device according to claim 2, wherein the inverter element includes an n-type field effect transistor and a p-type field effect transistor connected in series to each other,
Wherein the bias control signal comprises a high or low logic signal for controlling turn-on and turn-off of the n-type field effect transistor and the p-type field effect transistor. Battery bare cell; And
And a battery protection circuit module according to claim 2 or 3 connected to the battery bare cell.
Battery pack.

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