Method for on-line measurement of battery internal resistance, current operational module, and on-line measurement instrument for battery internal resistance

• US 20080284444A1
• Filed: 02/26/2008
• Published: 11/20/2008
• Est. Priority Date: 05/15/2007
• Status: Active Grant

• Current Assignee: Zhengzhou Runner Electric Co., Ltd.
• Original Assignee: Qinglan Li, Xiangchen Xu
• Inventors: Xu, Xiangchen, Li, Qinglan
• Granted Patent: US 8,217,659 B2
• Time in Patent Office: Days
• US Class Current: 324/430
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A method and a current operational module for on-line measurement of battery internal resistance and an on-line measurement instrument for battery internal resistance have high measurement accuracy and strong anti-interference ability. The on-line measurement instrument for battery internal resistance comprises a current work module, a voltage measurement module, an analog to digital conversion module, a signal generation module, a centre processing module, an Input/Output module, and a power supply module used for on-line measurement of battery internal resistance.

Claims

1. An on-line measurement method for battery internal resistance, comprising:

paralleled connecting two operational modules with a positive end and a negative end of the battery to be measured, wherein one module of the two operational modules is a current operational module which is used to generate an excitation signal and measure the excitation current passing through the battery under measurement, the other module of the two operational modules is a voltage measurement module which is used to measure excitation voltage between two ends of the battery under measurement, wherein

the current operational module adopts a load circuit discharging with a pulse Direct Current (DC) to generate the excitation signal,

the pulse DC has a DC component and a sine Alternating Current (AC) component,

the work power of the load circuit is supplied by an auxiliary power supply connected in series with the load circuit,

the discharging process of the load circuit is controlled by a signal generation module;

the voltage measurement module firstly adopts a stopping capacitor to remove DC component in the voltage signal, and adopts an operational amplifier to amplify the voltage signal, then adopts a high efficient digital filter for filtering;

the output current signal from the current operational module and the output voltage signal from the voltage measurement module are converted to digital signals by analog-to-digital converting, then the digital signal is sent to a central processing module,

the central processing module calculates the internal resistance of the battery under measurement according to the measured value of the current signal and the voltage signal.

2. The method according to claim 1, wherein

the current operational module adopts a precise current detection amplifier to perform current detection,

the load circuit, the precise current detection amplifier, and the auxiliary power supply are connected in series, and

the work power of the load circuit and the precise current detection amplifier are supplied by the auxiliary power supply.

3. The method according to claim 1, wherein, the signal generation module generates a pulse DC voltage signal to control the load circuit discharge with a pulse DC, the frequency of the sine AC component of the pulse DC voltage signal is 10 Hz-25 Hz.

4. The method according to claim 3, wherein, the output signal of the high efficient digital filter is output to the following circuits after passing through a resistance-capacitance coupled circuit;

the output signal of the load circuit or the precise current detection amplifier is output to the following circuits after passing through a stopping circuit.

5. The method according to claim 1, wherein, the measurement method is applicable to be used to measure resistance of a mental stick or a mental bar;

the auxiliary power supply is selected from a group including batteries or a DC voltage-stabilized supply.

6. A current operational module for on-line measurement of battery internal resistance, comprising

a load circuit discharging with a pulse DC,

a auxiliary power supply and

a stopping circuit,

wherein the pulse DC has a DC component and a sine AC component, the load circuit and the auxiliary power supply are connected in series, the output of the load circuit is connected with the input of the stopping circuit.

7. The current operational module according to claim 6, further comprising a precise current detection amplifier, wherein the precise current detection amplifier, the load circuit and the auxiliary power supply are connected in series, the output of the precise current detection amplifier is connected with the input of the stopping circuit.

8. The current operational module according to claim 7, wherein,

the load circuit comprises a triode (T1) and a triode (T2), the input of the load circuit is connected with the base of the triode (T1) through resistor (R4), the emitter of the triode (T1) is connected with the base of the triode (T2), the collector of the triode (T1) and the collector of the triode (T2) are connected together and connected with the negative end of the internal detection resistance of the precise current detection amplifier or connected with the positive end of the auxiliary power supply, the emitter of the triode (T1) and the emitter of the triode (T2) are connected with the negative end of the battery under measurement through resistor (R5) and resistor (R6) respectively;

the stopping circuit comprises capacitor (C0), resistor (R0) and resistor (R1), two ends of capacitor (C0) are respectively used as the input and the output of the stopping circuit, and two ends of capacitor (C0) are connected to ground through resistor (R0) and resistor (R1) respectively;

the input of the stopping circuit is connected with the emitter of the triode (T2), or connected with the output of the precise current detection amplifier;

the negative end of the auxiliary power supply is connected with the positive end of the battery under measurement.

9. The current operational module according to claim 8, further comprising an operational amplifier (IC2), wherein the input of the operational amplifier (IC2) is connected with the output of the stopping circuit.

10. The current operational module according to claim 9, wherein, the triode (T1) is a low power triode;

the triode (T2) is a high power triode;

the model of the precise current detection amplifier is one of a group including MAX471, MAX472, MAX4069, MAX4070, MAX4071, and MAX4072;

the model of the operational amplifier (IC2) is one of a group including TLC2272, TLC2274, AD822, AD824, OP200, AD708, TLC2264, TLC2262, TL062, TL064, and TL084;

the capacitance of capacitor (C0) is 5 μ

F-10 μ

F;

the resistance of resistor (R1) is 50 KΩ

-100 KΩ

;

the resistance of resistor (R0) is 2 KΩ

±

5%;

the auxiliary power supply is one of a group including a battery and a DC voltage-stabilized supply.

11. An on-line measurement instrument for battery internal resistance, comprising

a current operational module, a voltage measurement module, an analog to digital conversion module, a signal generation module, a central processing module, an Input/Output module, and a power supply module, wherein,

the current operational module and the voltage measurement module are paralleled connected to the positive end and the negative end of the battery under measurement,

the output of the current operational module and the output of the voltage measurement module are connected with analog to digital conversion input of the analog to digital conversion module,

the Input/Output of the central processing module are connected with the analog to digital conversion module, the signal generation module and the Input/Output Module,

the output of the signal generation module is connected with the input of the load circuit of the current operational module,

the output of the power supply module is connected with the power supply end of the current operational module, the voltage measurement module, the analog to digital conversion module, the signal generation module, the central processing module and the Input/Output module.

12. The on-line measurement instrument according to claim 11, wherein,

the voltage measurement module comprises a stopping capacitor, an operational amplifier, a high efficient digital filter, a microprocessor (IC13) used to generate a precise clock signal and a resistance-capacitance coupled circuit;

the stopping capacitor comprises capacitor (C10) and capacitor (C11), wherein one end of capacitor (C11) is connected with the negative end of the battery under measurement, the other end of capacitor (C11) is connected with the positive input of the operational amplifier (IC10), one end of capacitor (C10) is connected with the positive end of the battery under measurement, the other end of capacitor (C10) is connected with the negative input of operational amplifier (IC10),

the output of operational amplifier (IC10) is connected with the input of the high efficient digital filter through the operational amplifier (IC11), one output of the microprocessor (IC13) is connected with the clock input of the high efficient digital filter, the output of the high efficient digital filter is connected with the input of the resistance-capacitance coupled circuit, the output of the resistance-capacitance coupled circuit is connected with the input of the operational amplifier (IC14).

13. The on-line measurement instrument according to claim 12, wherein,

resistor (R10) and resistor (R11) are connected in series and then are paralleled connected between the positive input and the negative input of the operational amplifier (IC10), the connection point of resistor (R10) and resistor (R11) is either connected with ground or not connected with ground;

the resistance-capacitance coupled circuit comprises capacitor (C14) and resistor (R16), one end of capacitor (C14) is regarded as the input of the resistance-capacitance coupled circuit, the other end is regard as the output of the resistance-capacitance coupled circuit and connected with one end of resistor (R16), the other end of resistor (R16) is connected with ground.

14. The on-line measurement instrument according to claim 13, wherein,

the analog to digital conversion module comprises an analog to digital converter and a precise voltage reference source, the output of the precise voltage reference source is connected with the voltage reference input of the analog to digital converter, the positive end of the battery under measurement is connected with the analog to digital conversion input of the analog to digital conversion module;

the signal generation module comprises a microprocessor (IC30), a digital to analog converter, and an operational amplifier (IC32);

the data output of the microprocessor (IC30) is connected with the data input of the digital to analog converter, the output of the digital to analog converter is connected with the input of the operational amplifier (IC32), the output of the operational amplifier (IC32) is connected with the input of the load circuit;

the central processing module comprises a microprocessor (IC51), a temperature detector, a calendar clock generator, and a data memory,

the Input/Output of the microprocessor (IC51) are connected with the Input/Output of the temperature detector, the calendar clock generator, and the data memory,

the interrupt input of the microprocessor (IC51) is connected with the output of the microprocessor (IC30);

the Input/Output module comprises a serial port conversion module, a display, a keyboard and a printer;

the power supply module comprises a regulator.

15. The on-line measurement instrument according to claim 14, wherein, the model of the high efficient digital filter is one of a group including MAX291, MAX292, MAX295, MAX296, MAX293, MAX294, MAX297, and MAX280;

the model of the operational amplifiers (IC10) is one of a group including AD620, AD622, AD625;

the model of the operational amplifiers (IC11), (IC14) and (IC32) is one of a group including TLC2272, TLC2274, AD822, AD824, OP200, AD708, TLC2264, TLC2262, TL062, TL064, and TL084;

the model of the microprocessor (IC51) is PIC16C74;

the model of the microprocessor (IC30) is PIC16C54;

the model of the microprocessor (IC13) is PIC12C508;

the module of the analog to digital converter is one of a group including TLC2543, AD7888, AD5320, AD7871 and TLC2558;

the model of the precise reference voltage source is one of a group including MC1403, AD580, and LM113;

the model of the digital to analog converter is one of a group including DAC0832, AD7524, AD7533, AD558, TLC5620, TLC5617;

the model of the calendar clock generator is 12C887;

the model of the temperature detector is 18 B20;

the model of the data memory is 24C64;

the serial port conversion module is an RS-232 serial port conversion module;

the display is an LED display;

the capacitance of capacitor (C14) is 1-10 μ

F;

the resistance of resistor (R16) is 20 KΩ

-200 KΩ

.