CN101488589B - Method for measuring battery packs and their state of charge - Google Patents

Abstract

The invention discloses a battery component, wherein an interface for connecting the battery component and a portable electronic device is provided with at least three terminals, and the battery component comprises: battery, identification circuit and temperature perception circuit. In addition, the identification circuit is provided with an energy storage component and a current limiting component, and the temperature sensing circuit is provided with a switch and a temperature sensing component, wherein the temperature sensing component changes the impedance value of the battery component according to the temperature of the battery component. The portable electronic equipment judges the type of the battery component according to a charging line shape generated when the energy storage component is charged through the current limiting component, and then starts the temperature sensing circuit to judge the temperature of the battery component.

Description

Method for measuring battery packs and their state of charge

technical field

The present invention relates to a battery assembly, and in particular to a battery assembly for portable electronic equipment.

Background technique

The battery packs of a portable electronic device (such as a mobile phone, a personal digital assistant, a notebook computer, etc.) can have different models, and are used to provide the energy required for the operation of the portable electronic device. However, before charging the battery pack, it is necessary to determine the model of the battery pack in order to provide a current and voltage that meet the charging specifications of the battery pack of this type for charging. On the other hand, temperature is also an important criterion for judging the current and voltage during charging. If the temperature of the battery components is too high, the charging current should be reduced or the charging should be stopped to avoid damage to the battery due to overheating.

In order to obtain a signal related to the type and temperature of the battery pack to determine the state of charge, the prior art generally uses three electrodes or four electrodes disposed on the battery pack to obtain the signal. However, three electrodes have the advantage of reducing costs compared to four electrodes.

Figure 1 Figure 1a is a schematic diagram of an existing battery assembly. Referring to FIG. 1 , a conventional battery assembly 10 includes a battery 11 , a negative temperature coefficient thermistor NTC1 , resistors R1 , R2 , and electrodes 12 , 13 , 14 . The positive pole of the battery is coupled to the electrode 14 , the negative pole is coupled to the electrode 12 , the resistor R1 is connected in series with the resistor R2 , and the resistors R1 and R2 are respectively connected to the electrodes 11 and 12 . In addition, the negative temperature coefficient thermistor NTC1 is connected to the resistor R2 in parallel. Wherein, the battery assembly 10 receives electric energy through the electrode 13, and obtains an electric signal at the electrode 13, and the value of this electric signal is determined according to the equivalent resistance value of the negative temperature coefficient thermistor NTC1, resistors R1, R2, so by The type and temperature of the battery pack 10 can be deduced from the electrical signal.

Fig. 2a is a schematic diagram of the range of resistance values of existing different battery components. Please refer to Figure 1 and Figure 2a at the same time. If in the first type of battery, the values of resistors R1 and R2 are selected as R1' and R2', the range of equivalent resistance values of negative temperature coefficient thermistor NTC1, resistors R1 and R2 is R1'～R1 '+R2'. In the second type of battery, the values of resistors R1 and R2 are selected as R1", R2", then the range of equivalent resistance values of negative temperature coefficient thermistor NTC1, resistors R1 and R2 is R1"~R1" +R2".

When the equivalent resistance value falls within the range of R1'~R1'+R2', it is judged that the battery is the first type of battery and its temperature is estimated, and charging is carried out according to the charging specification of the battery. Similarly, when the equivalent resistance falls within the range of R1"-R1"+R2", it is judged that the battery is the second type of battery and its temperature is estimated, and charging is performed according to the charging specification of the battery.

Fig. 2b is another schematic diagram of the range of resistance values of existing different battery components. Please refer to Figure 1 and Figure 2b at the same time. If the ranges of the equivalent resistance values of the aforementioned two types of batteries overlap together, as shown in the overlapping range R1'～R1"+R2", then when the measured equivalent resistance value falls within the overlapping range R1 '～R1"+R2" (as shown by the oblique line in Figure 2b), it is impossible to deduce the type and temperature of the battery pack. In this way, the battery cannot be charged according to the charging specification of the battery. Therefore, in order to avoid such overlapping ranges of equivalent resistance values, it is necessary to narrow the ranges of equivalent resistance values of different types of batteries. However, narrowing the range of resistance values reduces the accuracy of temperature determination.

Therefore, it is necessary to design a battery pack and a charging device to overcome the above-mentioned problems and to accurately determine the type and temperature of the battery pack to adjust its charging state.

Contents of the invention

Therefore, an object of the present invention is to provide a battery assembly, which is installed in a portable electronic device, so that the portable electronic device can accurately determine the type and temperature of the battery, adjust the charging state, and reduce costs at the same time.

Another object of the present invention is to provide a charging state measuring method for accurately judging the type and temperature of the battery and adjusting the charging state of the battery.

According to the above objective of the present invention, a battery assembly is proposed, the interface of which is connected with a portable electronic device has a first terminal, a second terminal and a third terminal. The battery component includes: a battery, an identification circuit and a temperature sensing circuit, and the identification circuit has an energy storage component and a current limiting component, and the temperature sensing circuit has a switch and a temperature sensing component. On the other hand, the positive and negative poles of the battery are respectively coupled to the first terminal and the second terminal, and the identification circuit and the temperature sensing circuit are connected in series between the first terminal and the third terminal. The component connection relationship between the identification circuit and the temperature sensing circuit is as follows: one end of the energy storage component is coupled to the first terminal, the current limiting component is connected in series between the energy storage component and the third terminal, one end of the switch is coupled to the first terminal, and the temperature The sensing component is connected in series between the switch and the third terminal, and the temperature sensing component can change its resistance value according to the temperature of the battery component.

The portable electronic device uses a current to charge the energy storage component through the current limiting component to identify the model of the battery component, and then when the switch is turned on, the temperature sensing circuit will be activated to determine the temperature of the battery component.

According to the purpose of the present invention, an electronic device is proposed, which includes: a reference power supply, a battery assembly, and a charging state control device. The battery component includes: a battery, an identification circuit and a temperature sensing circuit, and the identification circuit has an energy storage component and a current limiting component, and the temperature sensing circuit has a switch and a temperature sensing component. On the other hand, the positive and negative poles of the battery are respectively connected to the first terminal and the second terminal, and the identification circuit and the temperature sensing circuit are connected in series between the first terminal and the third terminal. The component connection relationship between the identification circuit and the temperature sensing circuit is as follows: one end of the energy storage component is coupled to the first terminal, the current limiting component is connected in series between the energy storage component and the third terminal, one end of the switch is coupled to the first terminal, and the temperature The sensing component is connected in series between the switch and the third terminal, and the temperature sensing component can change its resistance value according to the temperature of the battery component.

Moreover, the state-of-charge control device identifies the model of the battery component based on the charging line generated when a current flows through the current limiting component to charge the energy storage component, and then the switch is turned on to activate the temperature sensing circuit to determine the temperature of the battery component. According to an embodiment of the present invention, the opening of the switch can be selectively controlled by, for example, a microcontroller reading the aforementioned charging line shape, or can be directly controlled by the charging potential of the energy storage component.

According to another object of the present invention, a method for measuring the state of charge is proposed, which is used to measure the type and temperature of a battery component. The method for measuring the state of charge includes: charging an energy storage component with a current through a current limiting component, and then Measuring a charging line shape of the energy storage component at a first preset time to determine the model of the battery component, then passing the current through a temperature sensing component, and then measuring the terminal of the temperature sensing component at a second preset time The voltage is used to judge the temperature of the battery pack.

It can be seen from the above description that the battery pack and its charging state measuring method of the present invention can accurately determine the model and temperature of the battery pack, and adjust the charging state. At the same time, since there is no need to increase the number of additional terminals, the cost reduction effect can be achieved.

Description of drawings

In order to make the above-mentioned and other purposes, features and advantages of the present invention more obvious and understandable, preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of a conventional battery assembly.

Fig. 2a is a schematic diagram of the range of resistance values of existing different battery components.

Fig. 2b is another schematic diagram of the range of resistance values of existing different battery components.

Fig. 3a is a schematic diagram illustrating a battery assembly according to an embodiment of the present invention.

Fig. 3b is a schematic diagram illustrating a battery assembly according to another embodiment of the present invention.

FIG. 4 is a schematic circuit diagram illustrating a battery assembly and a charging device according to a preferred embodiment of the present invention.

FIG. 5 is a graph showing the relationship between voltage and time of a battery assembly when being measured according to a preferred embodiment of the present invention.

FIG. 6 is a graph showing the relationship between voltage and time of a battery assembly when it is measured according to a preferred embodiment of the present invention.

Detailed ways

Since the charging and discharging curves of the energy storage component can be determined by the electrical parameters of itself and the connected current limiting component, different electrical parameters will produce different charging and discharging curves. The following embodiments of the present invention are designed according to the above characteristics, so as to accurately determine the model of the battery, and at the same time, can also determine the temperature of the battery to determine the state of charge of the battery.

The battery assembly and the charging device of the embodiments of the present invention are used in portable electronic devices, such as mobile phones, personal digital assistants, notebook computers, etc., and the following will take mobile phones as an example to illustrate the present invention Example.

Fig. 3a is a schematic diagram illustrating a battery assembly according to an embodiment of the present invention. Referring to FIG. 3 a , the battery assembly 30 includes a battery 31 , a battery identification circuit 32 and a temperature sensing circuit 33 , and has terminals 1 , 2 and 3 . The positive and negative poles of the battery are respectively coupled to the terminals 3 and 1, and the battery identification circuit 32 and the temperature sensing circuit 33 are arranged between the terminals 1 and 2. The battery type and temperature can be identified by the battery identification circuit 32 and the temperature sensing circuit 33 respectively.

Fig. 3b is a schematic diagram illustrating a battery assembly according to another embodiment of the present invention. The battery component 30 includes a battery 31 , a battery identification circuit 32 and a temperature sensing circuit 33 . The battery identification circuit 32 has an energy storage component 321 and a current limiting component 322 , and the temperature sensing circuit 33 has a switch 331 and a temperature sensing component 332 . Between terminals 1 and 2, an energy storage component 321 and a current limiting component 322 are connected in series, and a switch 331 and a temperature sensing component 332 are connected in series. Under this configuration, when the switch 331 is turned on, the temperature sensing component 332 is connected to the terminal 1 through the switch 331 . Preferably, the switching state of the switch 331 is controlled by the charging state of the energy storage component. On the other hand, the temperature sensing component 332 can change its resistance value according to the temperature of the battery component 30 .

A reference power supply can supply power to the state identification circuit 30 through the terminal 2, so that the current flows through the current limiting component 322 and charges the energy storage component 321, respectively at the terminal 2 at the first preset time t1 and the second preset time t2 For example, the voltage V1 and the voltage V2 are measured, the voltage V1 is used to determine the model of the battery assembly 30 , and the voltage V2 is used to determine the temperature of the battery assembly 30 . Generally speaking, the first predetermined time t1 is before the energy storage component 321 is fully stored with electric energy, and the second predetermined time t2 is after the energy storage component 321 is fully stored with electric energy.

In addition, it should be noted that the voltage V1 and the voltage V2 are only exemplary, and the voltage measured at the terminal 2 at the preset time t1 and the preset time t2 can be determined according to the numerical characteristics of the energy storage component 321 and the current limiting component 322. Sexual parameters, such as current I1, I2.

At the preset time t1, the switch 331 is closed, and the current flows through the current limiting component 322 to charge the energy storage component 321, so the value of the voltage V1 is determined according to the electrical parameters of the energy storage component 321 and the current limiting component 322. At the preset time t2, the energy storage component is in a steady state (steady state), at this time the switch 331 can be turned on to make the current flow through the temperature sensing component 332, so the value of the voltage V2 will be based on the electrical properties of the temperature sensing component 332 depends on the parameters.

In order to accurately grasp the charging state of the energy storage component 321 and improve the signal accuracy of the voltages V1 and V2, before the reference power supply is supplied to the energy storage component 321, the terminal 2 can be grounded by briefly turning on the switch SW to The energy in the energy storage component 321 is removed. By clearing the energy in the energy storage component 321 , the signal accuracy of the voltages V1 and V2 can be ensured so as to analyze the voltages V1 and V2 to accurately determine the type and temperature of the battery component 30 .

FIG. 4 is a schematic circuit diagram showing a battery pack and a charging device according to a preferred embodiment of the present invention. This charging device can be installed in a portable electronic device such as a mobile phone to charge the aforementioned battery pack. Charge. Please refer to FIG. 4 , a charging device 400 includes a connector 420 , a reference power supply 430 and a microcontroller (MCU) 440 for charging the battery pack 410 .

The battery assembly 410 can be regarded as a more detailed embodiment of the battery assembly 30 shown in FIG. (ie a switch) and a negative temperature coefficient thermistor 415 (ie a temperature sensing component) and electrodes 416 , 417 , 418 . The positive pole of the battery 411 is connected to the electrode 418 , and the negative pole thereof is coupled to the electrode 416 . Between the electrodes 416 and 417, a capacitor 412 and a resistor 413 are connected in series. In addition, the transistor 414 is located between the electrode 416 and the thermistor 415, and the gate is coupled to the node N1 connecting the capacitor 412 and the resistor 413, so the transistor 414 The switching state is controlled by the terminal voltage of the capacitor 412 . When the transistor 414 is turned on, the thermistor 415 is connected to the electrode 416 through the transistor 414 . On the other hand, the thermistor 415 is also coupled to the electrode 417 , and the thermistor 415 changes its resistance value according to the temperature of the battery assembly 410 .

The reference power supply 430 charges the capacitor 412 through the electrode 417 and the resistor 413. After the first preset time t1 and the second preset time t2 after the capacitor 412 starts charging, the microcontroller 440 can obtain the voltage V1, V2, and calculate and analyze according to the voltage values of the voltages V1 and V2 respectively to determine the type and temperature of the battery assembly 410 . Generally speaking, the first preset time t1 is before the capacitor 412 is fully stored with electric energy, and the preset time t2 is after the capacitor 412 is fully stored with electric energy.

The connector 420 includes electrodes 421 , 422 , 423 correspondingly connected to the electrodes 416 , 417 , 418 of the battery assembly 410 . The electrode 421 is grounded, the electrode 422 is coupled to the microcontroller 440 , and the electrode 423 can be coupled to the reference power supply 430 . The connector 420 is fixed in the mobile phone, and is used for transmitting the electric energy and the electric signal of the battery assembly 410 to the mobile phone, so as to provide the energy required for the mobile phone to operate.

The reference power supply 430 may include a reference voltage source 431 and a resistor 433. Optionally, the reference voltage source 431 may be coupled to the electrode 423 to input electric energy from the battery 411, and convert the electric energy to a constant voltage and supply it through the resistor 433 and the electrode 422. to electrode 417 to charge capacitor 412 through resistor 413 .

In addition, in an embodiment according to this preferred embodiment, a reference current source can be used instead of the reference voltage source 431, an inductor can be used instead of the capacitor 412, and a current control switch can be used instead of the NMOS transistor 414, which can also achieve accurate Determine the effect of the type and temperature of the battery pack.

The microcontroller 440 has an analog-to-digital converter (ADC) 441 and a control signal generator 443. The analog-to-digital converter 441 is used to convert the voltages V1 and V2 into digital signals respectively. The control signal generator 443 is used to convert the voltages V1 and V2 into digital signals according to the digital signals S1, S2 to generate a state-of-charge control signal Sc to control the state-of-charge of the battery pack 410 .

In order to accurately grasp the charging state of the capacitor 412 and improve the signal accuracy of the voltages V1 and V2, the charging device 400 uses, for example, an NMOS transistor 450 as a switch to ground the capacitor 412, and the gate of the transistor 450 is connected to the microcontroller 440 , the drain of which is connected to the electrode 422 and the source is grounded. That is to say, before the capacitor 412 is charged by the reference power source 430 , the electrode 417 is grounded through the transistor 450 to clear the energy in the capacitor 412 . The microcontroller 440 can output a control signal Sg to the gate of the transistor 450 to control the switching between the drain and the source of the transistor 450 .

By clearing the energy in the capacitor, the signal accuracy of the voltages V1 and V2 can be ensured so as to analyze the voltages V1 and V2 to accurately determine the type and temperature of the battery assembly 410 .

The switching state of the transistor 414 can be controlled by the charging potential of the capacitor 412. Originally, there is no charge in the capacitor 412, and the transistor 414 is turned off. When starting to charge the capacitor 412, the terminal voltage of the capacitor 412, that is, the voltage of the node N1 is still lower than the threshold voltage of the transistor 414, and the transistor 414 is still turned off. When the capacitor 412 is charged for a period of time (eg, fully charged), the voltage of the node N1 exceeds the threshold voltage of the transistor 414 , and the transistor 414 is turned on. In addition, in other embodiments, the turn-on and turn-off of the transistor 414 can also be selectively controlled by the microcontroller 440 , that is, the gate of the transistor 414 can also be connected to the microcontroller 440 .

FIG. 5 is a graph showing the relationship between voltage and time of a battery assembly when being measured according to a preferred embodiment of the present invention. Please refer to FIG. 4 and FIG. 5 at the same time. Before t=0, the microcontroller 440 may output the control signal Sg with a high level voltage to turn on the transistor 450 to ground the capacitor 412 to clear the charge in the capacitor. Afterwards, the microcontroller 440 outputs the control signal Sg having a low level voltage to turn off the transistor 450 .

After clearing the energy in the capacitor, the reference power supply 430 provides electric energy to the electrode 422, and the capacitor 412 starts charging. Since the terminal voltage of the capacitor 412 is still lower than the critical voltage of the transistor 415, the transistor 414 is still turned off at this time, and the current flows through the resistor 413 and capacitor 412 . The analog-to-digital converter 441 measures the voltage V1 on the electrode 417 via the node N2 at the first preset time t1, and converts it into a digital signal S1 for calculation and analysis. In this embodiment, since the voltage value V1 will vary with the product value RC of the capacitance value C of the capacitor 412 and the resistance value R of the resistor 413, it is only necessary to change the capacitance value C and resistance value R of different battery components, that is, The model of the battery pack can be determined. That is to say, different battery components have different RC values. The larger the RC, the smaller the voltage V1. >C3, then V1<V3. Therefore, the model of the battery pack 410 can be effectively determined by measuring and analyzing the values of the voltages V1 and V3.

FIG. 6 is a graph showing the relationship between voltage and time of a battery assembly when it is measured according to a preferred embodiment of the present invention. Please refer to FIG. 4 and FIG. 6 at the same time. After charging the capacitor 412 for a period of time, when the voltage of the node N1 exceeds the threshold voltage of the transistor 414 , the transistor is turned on, and the current flows through the thermistor 415 . At this time, the analog-to-digital converter 441 measures the voltage V2 on the electrode 417 via the node N2 at the second preset time t2 (the capacitor 412 is in a steady state), and converts it into a digital signal S2 for calculation and analysis. In this embodiment, since the voltage value V2 will change with the resistance value of the thermistor 415, and the resistance value of the thermistor 415 is determined according to the temperature of the battery assembly 410, the voltage value V2 will vary under different temperatures. Also different. Therefore, the model of the battery pack 410 can be effectively determined by measuring and analyzing the voltage value V2.

It can be seen from FIG. 6 that the analog-to-digital converter 441 receives the voltage values V1 and V2 on the electrode 417 at the first preset time t1 and the second preset time t2 in sequence. The voltage value V1 can be used to determine the model of the battery pack 410, and The voltage value V2 can be used to determine the temperature of the battery assembly 410 .

It should be noted that the thermistor 415 and the resistor 413 do not need to be connected to the electrode 417. Those skilled in the art of the present invention can use a plurality of electrodes to connect the thermistor 415 and the resistor 413 respectively. depart from the spirit and scope of the present invention.

It can be seen from the above-mentioned preferred embodiments of the present invention that by applying the charging assembly of the present invention, the battery assembly can be effectively and accurately judged by changing the electrical parameters of the energy storage assembly and the current limiting assembly without increasing the number of electrodes. The model and temperature of the battery, and determine its state of charge. Therefore, the charging assembly of the present invention not only solves the problems of the prior art, but also has the advantages of reducing the cost and improving the accuracy of charging state judgment.

Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various equivalent changes or replacements without departing from the spirit and scope of the present invention. , so the scope of protection of the present invention shall prevail as defined by the appended claims of the application.

Claims (10)

1. battery component, the interface that is connected with a portable electronic device has at least one the first terminal, one second terminal and one the 3rd terminal, and this battery component comprises:

One battery, its both positive and negative polarity couple this second terminal and this first terminal respectively;

One identification circuit comprises:

One energy storage component, an end couples this first terminal; And

One current limliting assembly is serially connected with between this energy storage component and the 3rd terminal, and wherein this energy storage component is an electric capacity, and this current limliting assembly then is a resistance; And

One temperature perception circuit comprises:

One switch, an end couples this first terminal; And

One temperature sense assembly is serially connected with between this switch and the 3rd terminal, and this temperature sense assembly changes its resistance value according to temperature,

Wherein in a period of time that this electric capacity begins to charge, measure the magnitude of voltage of the 3rd terminal, to determine the type of this battery component.

2. battery component according to claim 1 is characterized in that this switch open is when this energy storage component charges to a critical voltage.

3. battery component according to claim 1 is characterized in that the control end in order to the open and close of controlling this switch is coupled to the other end of this energy storage component.

4. battery component according to claim 1 is characterized in that this temperature sense assembly is a thermistor.

5. electronic installation comprises:

One reference power source;

One battery component comprises:

One battery, its both positive and negative polarity connect one second terminal and a first terminal respectively;

One identification circuit comprises:

One energy storage component, an end couples this first terminal; And

One current limliting assembly is serially connected with between this energy storage component and one the 3rd terminal; And

One temperature perception circuit comprises:

One switch, an end couples this first terminal; And

One temperature sense assembly is serially connected with between this switch and the 3rd terminal, and this temperature sense assembly changes its resistance value according to temperature; And

One charged state control device,

Wherein, the charging that this energy storage component was produced when this charged state control device charged to this energy storage component through this current limliting assembly by measuring an electric current is linear, judgement is in order to discern a model of this battery component, and when this switch open, this charged state control device is judged the temperature of this battery component by measuring the terminal voltage that is produced when this electric current is flowed through this temperature sense assembly.

6. electronic installation according to claim 5 is characterized in that this switch open is when this energy storage component charges to a critical voltage.

7. electronic installation according to claim 5 is characterized in that the control end in order to the open and close of controlling this switch is coupled to the other end of this energy storage component.

8. electronic installation according to claim 5 is characterized in that this first terminal ground connection, and this second terminal provides in order to the electric energy with this battery and gives this reference power source, and this reference power source couples the 3rd terminal so that this electric current to be provided.

9. electronic installation according to claim 5 is characterized in that this energy storage component is that an electric capacity, this current limliting assembly are a resistance and should temperature sense assembly were a thermistor.

10. a model and a method of temperature of measuring battery component comprises the following steps:

Make an electric current by the current limliting assembly energy storage component that charges;

One charging of measuring this energy storage component in one first Preset Time is linear, judges the model of this battery component according to this;

Make this electric current by a temperature sense assembly; And

Measure the terminal voltage of this temperature sense assembly in one second Preset Time, judge the temperature of this battery component according to this.

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