Battery internal resistance detection device, method, equipment and storage medium

Abstract

The present invention discloses a battery internal resistance detection device, method, equipment and storage medium. The method includes: obtaining first voltage data and first current data detected during a continuous time period when the power battery is discharging and conducting; obtaining second voltage data and second current data detected during a continuous time period when the power battery is discharging and turned off; determining the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data and the second current data. The present invention accurately determines the internal resistance of the power battery.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and particularly to a battery internal resistance detection device, method, equipment, and storage medium. Background Art

[0002] The power battery of a new energy vehicle is composed of a large number of battery cells connected in series and parallel. The performance of the battery cells determines the performance of the power battery system and the new energy vehicle. The internal resistance of the battery cells is a key parameter of the battery. A large internal resistance of the power battery will affect the use experience of the new energy vehicle and can indirectly characterize important information such as the health state and charge state of the battery. Due to technical limitations, existing new energy vehicles do not measure the internal resistance of the battery cells and cannot provide important evaluation parameters for battery management. Summary of the Invention

[0003] The main purpose of the present invention is to provide a battery internal resistance detection device, method, equipment, and storage medium, aiming to solve the problem of how to detect the internal resistance of a power battery.

[0004] To achieve the above object, a battery internal resistance detection device provided by the present invention includes:

[0005] A current detection module, which is connected to the power battery and is used to detect first current data of the power battery during a continuous discharge conduction period and second current data of the power battery during a continuous discharge shutdown period;

[0006] A voltage detection module, which is connected to the power battery and is used to detect first voltage data of the power battery during a continuous discharge conduction period and second voltage data of the power battery during a continuous discharge shutdown period;

[0007] A control module, which is respectively connected to the current detection module and the voltage detection module. The control module is used to obtain the first current data, the second current data, the first voltage data, and the second voltage data, and send the obtained data to a battery management system connected to the control module, so that the battery management system determines the internal resistance of the power battery.

[0008] In one embodiment, the current detection module includes an operational amplifier, a switch, and a preset resistor. The operational amplifier is connected in series with the preset resistor, and the control module controls the opening and closing of the switch.

[0009] In one embodiment, the battery internal resistance detection device includes a first positive interface, a first negative interface, a second positive interface, a second negative interface, a third positive interface, and a third negative interface. The current detection module is connected to the positive electrode of the power battery through the first positive interface and to the negative electrode of the power battery through the first negative interface. The voltage detection module is connected to the positive electrode of the power battery through the second positive interface and to the negative electrode of the power battery through the second negative interface. The control module is connected to the battery management system through the third positive interface and the third negative interface.

[0010] In one embodiment, the battery internal resistance detection device includes a fourth positive interface and a fourth negative interface. The current detection module, the voltage detection module, and the control module are all connected to the power supply system through the fourth positive interface and the fourth negative interface.

[0011] To achieve the above object, a battery internal resistance detection method provided by the present invention includes the following steps:

[0012] Obtain first voltage data and first current data detected during a continuous time period when the power battery is discharging and conducting;

[0013] Obtain second voltage data and second current data detected during a continuous time period when the power battery is discharging and closed;

[0014] Determine the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data.

[0015] In one embodiment, after the step of determining the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data, the method further includes:

[0016] Obtain measurement parameters of the power battery, where the measurement parameters include state of charge, temperature, and current data of the battery;

[0017] Determine the health state of the power battery according to the internal resistance and the measurement parameters.

[0018] In one embodiment, the step of determining the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data includes:

[0019] Determine a first internal resistance sequence according to the first voltage data and the first current data;

[0020] Determine a second internal resistance sequence according to the second voltage data and the second voltage data;

[0021] Determine the internal resistance of the power battery according to the resistance value distribution coefficient, the first internal resistance sequence value, and the second internal resistance sequence value.

[0022] In one embodiment, the step of determining the first internal resistance sequence according to the first voltage data and the first current data includes:

[0023] Determine the first initial voltage value in the first voltage data, and determine the first voltage difference sequence value between each voltage value in the first voltage data and the first initial voltage value;

[0024] Determine the first initial current value in the first current data, and determine the first current difference sequence value between each current value in the first current data and the first initial current value;

[0025] Determine the first internal resistance sequence value according to the first voltage difference sequence value and the first current difference sequence value;

[0026] The step of determining the second internal resistance sequence according to the second voltage data and the second current data includes:

[0027] Determine the second initial voltage value in the second voltage data, and determine the second voltage difference sequence value between each voltage value in the second voltage data and the second initial voltage value;

[0028] Determine the second initial current value in the second current data, and determine the second current difference sequence value between each current value in the second current data and the second initial current value;

[0029] Determine the second internal resistance sequence value according to the second voltage difference sequence value and the second current difference sequence value.

[0030] To achieve the above object, the present invention also provides a battery internal resistance detection device, which includes a memory, a processor, and a battery internal resistance detection program stored in the memory and executable on the processor. When the battery internal resistance detection program is executed by the processor, each step of the battery internal resistance detection method described above is implemented.

[0031] To achieve the above object, the present invention also provides a computer-readable storage medium, which stores a battery internal resistance detection program. When the battery internal resistance detection program is executed by a processor, each step of the battery internal resistance detection method described above is implemented.

[0032] A battery internal resistance detection device, method, equipment and storage medium provided by the present invention obtain first voltage data and first current data detected during a continuous time period when a power battery is discharging and conducting; obtain second voltage data and second current data detected during a continuous time period when the power battery is discharging and closed; and determine the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data and the second current data. By using the voltage data and current data during the continuous time period of discharging and conducting, and the voltage data and current data during the continuous time period of discharging and closing, the internal resistance of the power battery is accurately determined, which is convenient for the health status management of the power battery. Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of the battery internal resistance detection device according to an embodiment of the present invention;

[0034] Figure 2 It is a schematic structural diagram of the battery internal resistance detection device, the battery internal resistance detection device and the battery management system according to an embodiment of the present invention;

[0035] Figure 3 It is a schematic structural diagram of the battery internal resistance detection device according to an embodiment of the present invention;

[0036] Figure 4 It is a schematic hardware structure diagram of the battery internal resistance detection equipment according to an embodiment of the present invention;

[0037] Figure 5 It is a schematic flowchart of the first embodiment of the battery internal resistance detection method of the present invention;

[0038] Figure 6 It is a schematic detailed flowchart of step S30 of the second embodiment of the battery internal resistance detection method of the present invention.

[0039]

[0040]

[0041] The realization, functional characteristics and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiment

[0042] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] The main solution of the embodiment of the present invention is: obtaining first voltage data and first current data detected during a continuous time period when the power battery is discharging and conducting; obtaining second voltage data and second current data detected during a continuous time period when the power battery is discharging and turned off; determining the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data.

[0044] By using the voltage data and current data during the continuous time period of discharging and conducting, and the voltage data and current data during the continuous time period of discharging and turned off, the internal resistance of the power battery is accurately determined, which is convenient for the health status management of the power battery.

[0045] Referring to Figure 1 and Figure 2 , the present invention provides a battery internal resistance detection device U2, and the battery internal resistance detection device U2 includes:

[0046] A current detection module U21, the current detection module U21 is connected to the power battery U1, and is used for detecting first current data of the power battery U1 during a continuous time period when the power battery U1 is discharging and conducting, and second current data of the power battery U1 during a continuous time period when the power battery U1 is discharging and turned off;

[0047] A voltage detection module U22, the voltage detection module U22 is connected to the power battery U1, and is used for detecting first voltage data of the power battery U1 during a continuous time period when the power battery U1 is discharging and conducting, and second voltage data of the power battery U1 during a continuous time period when the power battery U1 is discharging and turned off;

[0048] A control module U23, the control module U23 is respectively connected to the current detection module U21 and the voltage detection module U22, the control module U23 is used for obtaining the first current data, the second current data, the first voltage data, and the second voltage data, and sending the obtained data to a battery management system U3 connected to the control module U23, so that the battery management system U3 determines the internal resistance of the power battery U1.

[0049] As Figure 3 shown, optionally, the current detection module U21 includes an operational amplifier AM1 for current detection, a switch W, and a preset resistor R, the operational amplifier AM1 is connected in series with the preset resistor R, and the control module U23 controls the opening and closing of the switch W.

[0050] Optionally, the voltage detection module U22 includes an operational amplifier AM2 for voltage detection.

[0051] Optionally, the control module U23 includes an analog front-end circuit AFE.

[0052] The module interfaces of the battery internal resistance detection device U2 include a first positive interface S+, a first negative interface S-, a second positive interface F+, a second negative interface F-, a third positive interface C+, and a third negative interface C-. Optionally, the current detection module U21 is connected to the positive electrode of the power battery U1 through the first positive interface S+ and to the negative electrode of the power battery U1 through the first negative interface S-. The voltage detection module U22 is connected to the positive electrode of the power battery U1 through the second positive interface F+ and to the negative electrode of the power battery U1 through the second negative interface F-. The control module U23 is connected to the battery management system U3 through the third positive interface C+ and the third negative interface C-.

[0053] Optionally, as Figure 3 shown, inside the battery internal resistance detection device U2, the first positive interface S+ is connected to one foot of the switch W, the other foot of the switch W is connected to one foot of the resistor R, the other foot of the resistor R is connected to the first negative interface S-, and the two feet of the resistor R are respectively connected to the input + and input - of the operational amplifier AM1 for current detection. The output of the operational amplifier AM1 is connected to the sampling channel A of the analog front-end circuit AFE. The second positive interface F+ is connected to the input + of the operational amplifier AM2 for voltage sampling, the second negative interface F- is connected to the input - of the operational amplifier AM2, and the output of the operational amplifier AM2 is connected to the channel B of the analog front-end AFE. The power supplies of the operational amplifier AM1 and the operational amplifier AM2 are respectively connected to the fourth positive interface P+ and the fourth negative interface P-. The channel IO of the analog front-end circuit AFE is connected to the control foot of the discharge switch W. The power supplies of the analog front-end circuit AFE are respectively connected to the fourth positive interface P+ and the fourth negative interface P-. The communication of the analog front-end circuit AFE is respectively connected to the third positive interface C+ and the third negative interface C-. Optionally, the measurement times of the operational amplifier AM1 and the operational amplifier AM2 are synchronized.

[0054] Optionally, the module interfaces of the battery internal resistance detection device U2 are respectively a first positive interface S+, a first negative interface S-, a second positive interface F+, a second negative interface F-, a third positive interface C+, a third negative interface C-, a fourth positive interface P+, and a fourth negative interface P-. The current detection module U21, the voltage detection module U22, and the control module U23 are all connected to the power supply system (not shown) through the fourth positive interface P+ and the fourth negative interface P-.

[0055] In the technical solution of this embodiment, the current detection module U21 and the voltage detection module U22 in the battery internal resistance detection device U2 are high-voltage sampling circuits. The high-speed sampling circuit has no impedance loop at both ends of the relay, and the sampling circuit has no high-voltage safety risk to the power distribution. By using the characteristic changes of the voltage of the high-voltage sampling point to the ground when the relay is closed and cut off, the safety and reliability of the high-voltage power distribution are improved. And the battery internal resistance detection device U2 uses the ground as the sampling reference point, and the sampling circuit structure is simple and the cost is low.

[0056] As an implementation solution, the battery internal resistance detection device can be as Figure 4 shown.

[0057] The solution of the embodiment of the present invention relates to a battery internal resistance detection device, which includes: a processor 101, such as a CPU, a memory 102, and a communication bus 103. Among them, the communication bus 103 is used to realize the connection and communication between these components.

[0058] The memory 102 can be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. As Figure 4 shown, the memory 102, as a computer-readable storage medium, may include a battery internal resistance detection program; and the processor 101 can be used to call the battery internal resistance detection program stored in the memory 102 and perform the following operations:

[0059] Obtain the first voltage data and the first current data detected during the continuous discharge conduction period of the power battery;

[0060] Obtain the second voltage data and the second current data detected during the continuous discharge shutdown period of the power battery;

[0061] Determine the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data.

[0062] In one embodiment, the processor 101 can be used to call the battery internal resistance detection program stored in the memory 102 and perform the following operations:

[0063] Obtain the measurement parameters of the power battery, where the measurement parameters include the state of charge, temperature, and current data of the battery;

[0064] Determine the health state of the power battery according to the internal resistance and the measurement parameters.

[0065] In one embodiment, the processor 101 can be used to call the battery internal resistance detection program stored in the memory 102 and perform the following operations:

[0066] Determine a first internal resistance sequence according to the first voltage data and the first current data;

[0067] Determine a second internal resistance sequence according to the second voltage data and the second voltage data;

[0068] Determine the internal resistance of the power battery according to the resistance distribution coefficient, the first internal resistance sequence value, and the second internal resistance sequence value.

[0069] In one embodiment, the processor 101 may be used to call the battery internal resistance detection program stored in the memory 102 and perform the following operations:

[0070] Determine the first initial voltage value in the first voltage data, and determine the first voltage difference sequence values of each voltage value in the first voltage data and the first initial voltage value;

[0071] Determine the first initial current value in the first current data, and determine the first current difference sequence values of each current value in the first current data and the first initial current value;

[0072] Determine the first internal resistance sequence values according to the first voltage difference sequence values and the first current difference sequence values;

[0073] Determine the second initial voltage value in the second voltage data, and determine the second voltage difference sequence values of each voltage value in the second voltage data and the second initial voltage value;

[0074] Determine the second initial current value in the second current data, and determine the second current difference sequence values of each current value in the second current data and the second initial current value;

[0075] Determine the second internal resistance sequence values according to the second voltage difference sequence values and the second current difference sequence values.

[0076] Based on the above hardware architecture of the battery internal resistance detection device, an embodiment of the battery internal resistance detection method of the present invention is proposed.

[0077] Refer to Figure 5 , Figure 5 This is the first embodiment of the battery internal resistance detection method of the present invention. The battery internal resistance detection method includes the following steps:

[0078] Step S10, obtain the first voltage data and the first current data detected during the continuous time period of the power battery discharging and conducting;

[0079] Specifically, one or more power batteries can be selected in the power battery pack for internal resistance measurement to determine the health status of the power battery. Since the power batteries have a certain degree of consistency, the working current of the battery cells in series is the same, and the health status is basically the same. Therefore, the health status of a certain one or more power batteries can characterize the health status of the entire battery pack to a certain extent.

[0080] The first voltage data are the instantaneous voltage data detected within a continuous discharge conduction time period, and the first current data are the instantaneous current data detected within a continuous discharge conduction time period. Optionally, the power battery is discharged by controlling the switch of the current detection module, and the first current data are obtained through high-speed sampling. Optionally, the continuous discharge conduction time period includes a plurality of consecutive detection times: [ts0, ts1, ts2,..., tsn]. Optionally, the discharge has not been conducted at time ts0, and the discharge is conducted at time ts1. The first voltage data detected within the continuous discharge conduction time period are [us0, us1, us2,..., usn], and the first current data are [is0, is1, is2,..., isn].

[0081] Optionally, for the continuous voltage signal detected within the continuous discharge conduction time period, the first voltage data are obtained by sampling the continuous voltage signal, and for the continuous current signal detected within the continuous discharge conduction time period, the first current data are obtained by sampling the continuous current signal.

[0082] Step S20: Obtain the second voltage data and the second current data detected by the power battery within a continuous discharge-off time period;

[0083] Specifically, the second voltage data are the instantaneous voltage data detected within a continuous discharge-off time period, and the second current data are the instantaneous current data detected within a continuous discharge-off time period. Optionally, the power battery is discharged by controlling the switch of the current detection module, and the second current data are obtained through high-speed sampling. Optionally, the continuous discharge-off time period includes a plurality of consecutive detection times: [te0, te1, te2,..., tem], where the discharge has not been turned off at time te0, and the discharge is turned off at time te1. The second voltage data are [ue0, ue1, ue2,..., uem], and the second current data are [ie0, ie1, ie2,..., iem].

[0084] Optionally, for the continuous voltage signal detected within the continuous discharge-off time period, the second voltage data are obtained by sampling the continuous voltage signal, and for the continuous current signal detected within the continuous discharge-off time period, the second current data are obtained by sampling the continuous current signal.

[0085] Step S30: Determine the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data.

[0086] Specifically, the internal resistance of the power battery is determined based on a preset resistance distribution coefficient, first voltage data, first current data, second voltage data, and second current data. Optionally, the resistance distribution coefficient is jointly determined by factors such as the voltage and current measurement frequency, measurement time and switch operation delay, cell characteristics, voltage and current measurement deviation coefficients, etc., and is usually determined through testing and calibration.

[0087] Optionally, the first internal resistance of the power battery is determined based on a preset resistance distribution coefficient, first voltage data, and first current data, the second internal resistance of the power battery is determined based on a preset resistance distribution coefficient, second voltage data, and second current data, and the internal resistance of the power battery is determined based on the average value of the first internal resistance and the second internal resistance.

[0088] Optionally, a first internal resistance sequence is determined based on the first voltage data and the first current data; a second internal resistance sequence is determined based on the second voltage data and the second voltage data; and the internal resistance of the power battery is determined based on the resistance distribution coefficient, the values of the first internal resistance sequence, and the values of the second internal resistance sequence.

[0089] Optionally, the internal resistance of the power battery is obtained by analyzing the change trends, time phases, and steady-state values of the first voltage data, first current data, second voltage data, and third current data.

[0090] Optionally, after step S30, the state of health of the power battery is calculated based on the internal resistance, as shown in the following formula:

[0091]

[0092] where SOH represents the state of health of the power battery, R EOL represents the internal resistance at the end of the battery life, R C represents the current internal resistance of the battery, R new represents the internal resistance of a brand-new battery.

[0093] Optionally, after step S30, measurement parameters of the power battery are obtained, where the measurement parameters include state of charge, temperature, and current data; the health state of the power battery is determined based on the internal resistance and the measurement parameters. Optionally, the battery state scores of the power battery are respectively determined according to the internal resistance, state of charge, temperature, and current data. Optionally, the state scores are determined according to the ranges to which the internal resistance, temperature, and current data belong. Optionally, the state of charge is the ratio of the remaining capacity of the power battery after being used for a period of time or left unused for a long time to the capacity in the fully charged state, usually expressed as a percentage, and the score of the state of charge is determined according to the ratio. After determining the scores corresponding to the respective parameters, the weight parameters corresponding to the respective scores are determined, and the health state of the power battery is determined based on the respective scores and the weight parameters. Optionally, the specific formula of the function f is comprehensively determined from the cell test data and the detailed data of the electric vehicle used, or the parameters of the function f can be obtained by training with a neural network model. Exemplarily, as shown in the following formula:

[0094] SOH = f(R, SOC, T, I);

[0095] where SOH represents the health state of the power battery, R represents the internal resistance of the power battery, SOC represents the state of charge, T represents the temperature, and I represents the current.

[0096] In the technical solution of this embodiment, first voltage data and first current data detected during a continuous discharge conduction time period of the power battery are obtained; second voltage data and second current data detected during a continuous discharge cut-off time period of the power battery are obtained; the internal resistance of the power battery is determined based on a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data. By using the voltage data and current data during the continuous discharge conduction time period and the voltage data and current data during the continuous discharge cut-off time period, the internal resistance of the power battery is accurately determined, facilitating the health state management of the power battery.

[0097] Referring to Figure 6 , Figure 6 This is the second embodiment of the battery internal resistance detection method of the present invention. Based on the first embodiment, the step S30 includes:

[0098] Step S31, determining a first internal resistance sequence based on the first voltage data and the first current data;

[0099] Step S32, determining a second internal resistance sequence based on the second voltage data and the second voltage data;

[0100] Step S33, determining the internal resistance of the power battery based on the resistance distribution coefficient, the values of the first internal resistance sequence, and the values of the second internal resistance sequence.

[0101] Optionally, determine the first ratio of each voltage in the first voltage data to the current in the corresponding first current data, and determine the first internal resistance sequence value according to the first ratio, as shown in the following formula:

[0102] rs0 = us1 / is1, rs1 = us1 / is1, rs2 = us2 / is2,..., rsn = usn / isn;

[0103] where, [rs0, rs1, rs2,..., rsn] is the first internal resistance sequence value, [us0, us1, us2,..., usn] is the first voltage data, and [is0, is1, is2,..., isn] is the first current data.

[0104] Optionally, determine the second ratio of each voltage in the second voltage data to the current in the corresponding second current data, and determine the second internal resistance sequence value according to the second ratio, as shown in the following formula:

[0105] re0 = ue1 / ie1, re1 = ue1 / ie1, re2 = ue2 / ie2,..., ren = uen / ien;

[0106] where, [re0, re1, re2,..., ren] is the second internal resistance sequence value, [ue0, ue1, ue2,..., uen] is the second voltage data, and [ie0, ie1, ie2,..., ien] is the second current data.

[0107] Optionally, determine the first initial voltage value us0 in the first voltage data, and determine the first voltage difference sequence value of each voltage value in the first voltage data and the first initial voltage value us0; determine the first initial current value is0 in the first current data, and determine the first current difference sequence value of each current value in the first current data and the first initial current value is0; determine the first internal resistance sequence value according to the first voltage difference sequence value and the first current difference sequence value. Exemplarily, as shown in the following formula:

[0108] rs1 = (us1 - us0) / (is1 - is0);

[0109] rs2 = (us2 - us0) / (is2 - is0); ...

[0110] rsn = (usn - us0) / (isn - is0);

[0111] where, [rs1, rs2,..., rsn] is the first internal resistance sequence value, [us0, us1, us2,..., usn] is the first voltage data, and [is0, is1, is2,..., isn] is the first current data.

[0112] Determine the second initial voltage value ue0 in the second voltage data, and determine the second voltage difference sequence values of each voltage value in the second voltage data and the second initial voltage value ue0; determine the second initial current value ie0 in the second current data, and determine the second current difference sequence values of each current value in the second current data and the second initial current value ie0; determine the second internal resistance sequence values according to the second voltage difference sequence values and the second current difference sequence values. Exemplarily, as shown in the following formula:

[0113] re1 = (ue1 - ue0) / (ie1 - ie0);

[0114] re2 = (ue2 - ue0) / (ie2 - ie0); ...

[0115] rem = (uem - ue0) / (iem - ie0);

[0116] Wherein, [re1, re2,..., ren] is the second internal resistance sequence value, [ue0, ue1, ue2,..., uen] is the second voltage data, and [ie0, ie1, ie2,..., ien] is the second current data.

[0117] Optionally, determine the first voltage difference sequence values of adjacent voltage values in the first voltage data, determine the first current difference sequence values of adjacent current values in the first current data, and determine the first internal resistance sequence values according to the first voltage difference sequence values and the first current difference sequence values. Exemplarily, as shown in the following formula:

[0118] rs j = (us j - us j-1 ) / (is j - is j-1 ), j = 1, 2,..., n

[0119] Wherein, [rs1, rs2,..., rsn] is the first internal resistance sequence value, [us0, us1, us2,..., usn] is the first voltage data, and [is0, is1, is2,..., isn] is the first current data.

[0120] Determine the second voltage difference sequence values of adjacent voltage values in the second voltage data, determine the second current difference sequence values of adjacent current values in the second current data, and determine the second internal resistance sequence values according to the second voltage difference sequence values and the second current difference sequence values;

[0121] re s = (ue s - ue s-1 ) / (ies -ie s-1 ), s = 1, 2, ..., m

[0122] Wherein, [re1, re2, ..., ren] is the second internal resistance sequence value, [ue0, ue1, ue2, ..., uen] is the second voltage data, and [ie0, ie1, ie2, ..., ien] is the second current data.

[0123] Determine the internal resistance of the power battery according to the resistance distribution coefficient, the first internal resistance sequence value and the second internal resistance sequence value. Optionally, obtain the first resistance distribution coefficient corresponding to each internal resistance value in the first internal resistance sequence value, determine the first product of each internal resistance value and the corresponding first resistance distribution coefficient, and determine the first sum value according to the first product; obtain the second resistance distribution coefficient corresponding to each internal resistance value in the second internal resistance sequence value, determine the second product of each internal resistance value and the corresponding second resistance distribution coefficient, and determine the second sum value according to the second product; determine the internal resistance of the power battery according to the first sum value and the second sum value.

[0124] R = a1 * rs1 + a2 * rs2 +, ..., an * rsn + b1 * re1 + b2 * re2 +, ..., bn * rem

[0125] Wherein, a1, a2, ..., an are the first resistance distribution coefficients, b1, b2, ..., bm are the second resistance distribution coefficients, [re1, re2, ..., ren] is the second internal resistance sequence value, and [re1, re2, ..., ren] is the second internal resistance sequence value.

[0126] In the technical solution of this embodiment, determine the first internal resistance sequence according to the first voltage data and the first current data; determine the second internal resistance sequence according to the second voltage data and the second voltage data; determine the internal resistance of the power battery according to the resistance distribution coefficient, the first internal resistance sequence value and the second internal resistance sequence value. By using the voltage data and current data during the continuous time period of discharge conduction and the voltage data and current data during the continuous time period of discharge shutdown, the internal resistance of the power battery is accurately determined, which is convenient for the health status management of the power battery.

[0127] The present invention also provides a battery internal resistance detection device, which includes a memory, a processor, and a battery internal resistance detection program stored in the memory and executable on the processor. When the battery internal resistance detection program is executed by the processor, it realizes each step of the battery internal resistance detection method described in the above embodiment.

[0128] The present invention also provides a computer-readable storage medium storing a battery internal resistance detection program, and when the battery internal resistance detection program is executed by a processor, each step of the battery internal resistance detection method described in the above embodiments is implemented.

[0129] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0130] It should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, system, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, system, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the presence of additional identical elements in the process, system, article or device including the element.

[0131] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described embodiment system can be implemented by means of software plus a necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product is stored in a computer-readable storage medium as described above (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which may be a mobile phone, a computer, a parking management device, an air conditioner, or a network device, etc.) to execute the system described in each embodiment of the present invention.

[0132] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present invention.

Claims

1. A battery internal resistance detection device, characterized in that, the battery internal resistance detection device includes: a current detection module, which is connected to the power battery and is used to detect the first current data of the power battery during a continuous discharge conduction time period and the second current data of the power battery during a continuous discharge shutdown time period; the continuous discharge conduction time period includes a plurality of consecutive detection moments, including the detection moment when the discharge has not yet conducted and the detection moment when the discharge is conducting; the continuous discharge shutdown time period includes a plurality of consecutive detection moments, including the detection moment when the discharge has not yet shut down and the detection moment when the discharge is shut down; a voltage detection module, which is connected to the power battery and is used to detect the first voltage data of the power battery during a continuous discharge conduction time period and the second voltage data of the power battery during a continuous discharge shutdown time period; a control module, which is respectively connected to the current detection module and the voltage detection module. The control module is used to obtain the first current data, the second current data, the first voltage data and the second voltage data, and send the obtained data to a battery management system connected to the control module, so that the battery management system determines the internal resistance of the power battery according to a preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data and the second current data.

2. The battery internal resistance detection device according to claim 1, characterized in that, the current detection module includes an operational amplifier, a switch and a preset resistor. The operational amplifier is connected in series with the preset resistor, and the control module controls the opening and closing of the switch.

3. The battery internal resistance detection device according to claim 1 or 2, characterized in that, the battery internal resistance detection device includes a first positive interface, a first negative interface, a second positive interface, a second negative interface, a third positive interface and a third negative interface. The current detection module is connected to the positive electrode of the power battery through the first positive interface and to the negative electrode of the power battery through the first negative interface. The voltage detection module is connected to the positive electrode of the power battery through the second positive interface and to the negative electrode of the power battery through the second negative interface. The control module is connected to the battery management system through the third positive interface and the third negative interface.

4. The battery internal resistance detection device according to claim 3, characterized in that, the battery internal resistance detection device includes a fourth positive interface and a fourth negative interface. The current detection module, the voltage detection module and the control module are all connected to the power supply system through the fourth positive interface and the fourth negative interface.

5. A battery internal resistance detection method, characterized in that, applied to the battery internal resistance detection device according to any one of claims 1-4, the method includes: obtaining the first voltage data and the first current data detected by the power battery during a continuous discharge conduction time period; obtaining the second voltage data and the second current data detected by the power battery during a continuous discharge shutdown time period; Determine the internal resistance of the power battery according to the preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data.

6. The battery internal resistance detection method according to claim 5, wherein, after the step of determining the internal resistance of the power battery according to the preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data, further includes: Obtain the measurement parameters of the power battery, where the measurement parameters include state of charge, temperature, and current data of the battery; Determine the health state of the power battery according to the internal resistance and the measurement parameters.

7. The battery internal resistance detection method according to claim 5, wherein, the step of determining the internal resistance of the power battery according to the preset resistance distribution coefficient, the first voltage data, the first current data, the second voltage data, and the second current data includes: Determine the first internal resistance sequence according to the first voltage data and the first current data; Determine the second internal resistance sequence according to the second voltage data and the second current data; Determine the internal resistance of the power battery according to the resistance distribution coefficient, the value of the first internal resistance sequence, and the value of the second internal resistance sequence.

8. The battery internal resistance detection method according to claim 7, wherein, the step of determining the first internal resistance sequence according to the first voltage data and the first current data includes: Determine the first initial voltage value in the first voltage data, and determine the first voltage difference sequence value between each voltage value in the first voltage data and the first initial voltage value; Determine the first initial current value in the first current data, and determine the first current difference sequence value between each current value in the first current data and the first initial current value; Determine the first internal resistance sequence value according to the first voltage difference sequence value and the first current difference sequence value; the step of determining the second internal resistance sequence according to the second voltage data and the second current data includes: Determine the second initial voltage value in the second voltage data, and determine the second voltage difference sequence value between each voltage value in the second voltage data and the second initial voltage value; Determine the second initial current value in the second current data, and determine the second current difference sequence value between each current value in the second current data and the second initial current value; Determine the second internal resistance sequence value according to the second voltage difference sequence value and the second current difference sequence value.

9. A battery internal resistance detection device, wherein, the battery internal resistance detection device includes a memory, a processor, and a battery internal resistance detection program stored in the memory and executable on the processor. When the battery internal resistance detection program is executed by the processor, it implements each step of the battery internal resistance detection method according to any one of claims 5-8.

10. A computer-readable storage medium, wherein, the computer-readable storage medium stores a battery internal resistance detection program. When the battery internal resistance detection program is executed by a processor, it implements each step of the battery internal resistance detection method according to any one of claims 5-8.

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