A battery management system, a voltage and temperature detection method thereof, and an electronic device

Abstract

The present invention relates to a battery management system and its voltage and temperature detection method, as well as an electronic device. The method comprises: a voltage acquisition unit and a switch unit connected to the voltage acquisition unit. The method includes: obtaining voltage information and collected temperature information from the voltage acquisition unit; obtaining transmission temperature information from the switch unit; detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information; and if so, outputting a voltage acquisition function abnormality alarm; and detecting whether the temperature acquisition function of the switch unit is abnormal based on the collected temperature information and the transmission temperature information; and if so, outputting a temperature acquisition function abnormality alarm. The present invention can detect the voltage and temperature detection functions of the battery management system and provide a warning of functional abnormality, meeting functional safety requirements. It can be implemented without adding redundant chips, significantly reducing costs and effectively reducing product size pressures.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and more particularly to a battery management system, a voltage and temperature detection method thereof, and an electronic device. Background Art

[0002] With the development of power batteries, safety is gaining increasing attention across all industries. Functional safety standards in the lithium battery industry place high demands on battery management systems (BMSs). Meeting these requirements generally requires dual protection and a dual-chip architecture. The biggest drawback of this approach is that it essentially doubles the cost and approximately doubles the size of the BMS. Furthermore, the number of components required significantly increases, placing significant pressure on both cost and size.

[0003] However, as customer demands increase, reducing costs and BMS size is a must. Therefore, how to achieve functional safety requirements with the least number of components has become an urgent problem that needs to be solved. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a battery management system and a voltage and temperature detection method and an electronic device thereof, in view of the defects of the prior art.

[0005] The technical solution adopted by the present invention to solve the technical problem is to construct a voltage and temperature detection method for a battery management system, the battery management system comprising: a voltage acquisition unit and a switch unit connected to the voltage acquisition unit; the voltage and temperature detection method comprising the following steps:

[0006] Acquiring voltage information and temperature information from the voltage acquisition unit;

[0007] acquiring transmission temperature information of the switch unit;

[0008] detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information, and outputting abnormal alarm information of the voltage acquisition function of the voltage acquisition unit if abnormal;

[0009] Based on the collected temperature information and the transmitted temperature information, it is detected whether the temperature collection function of the switch unit is abnormal. If abnormal, abnormal alarm information of the temperature collection function of the switch unit is output.

[0010] In the voltage and temperature detection method of the battery management system of the present invention, the voltage acquisition unit includes: an analog front-end chip; the voltage information includes: power supply information of the analog front-end chip and battery cell voltage data;

[0011] The detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information, and if abnormal, outputting abnormal alarm information of the voltage acquisition function of the voltage acquisition unit includes:

[0012] Determining whether the power supply function of the analog front-end chip is normal according to the power supply information;

[0013] If the power supply function of the analog front-end chip is abnormal, outputting the analog front-end chip power supply abnormality alarm information;

[0014] If the power supply function of the analog front-end chip is normal, determining whether the voltage acquisition function of the analog front-end chip is abnormal according to the battery cell voltage data;

[0015] If the voltage acquisition function of the analog front-end chip is abnormal, alarm information of the voltage acquisition function of the analog front-end chip is output.

[0016] In the voltage and temperature detection method for a battery management system according to the present invention, judging whether the power supply function of the analog front-end chip is normal according to the power supply information includes:

[0017] Obtaining a reference value of a reference source of the analog front-end chip;

[0018] After dividing the reference value of the reference source, a divided voltage value is obtained;

[0019] Inputting the divided voltage value into the divided voltage input port of the analog front-end chip;

[0020] Obtaining the divided voltage value through the divided voltage input port;

[0021] Whether the power supply function of the analog front-end chip is normal is judged according to the voltage division value and the reference value of the reference source.

[0022] In the voltage and temperature detection method for a battery management system according to the present invention, judging whether the power supply function of the analog front-end chip is normal based on the voltage division value and the reference value of the reference source includes:

[0023] Comparing the voltage division value with the reference value of the reference source;

[0024] If the voltage division value is equal to the reference value of the reference source and the voltage division value is within a preset voltage range, it is determined that the power supply function of the analog front-end chip is normal; otherwise, it is determined that the power supply function of the analog front-end chip is abnormal.

[0025] In the voltage and temperature detection method of the battery management system of the present invention, if the power supply function of the analog front-end chip is normal, determining whether the voltage acquisition function of the analog front-end chip is abnormal based on the battery cell voltage data includes:

[0026] If the power supply function of the analog front-end chip is normal, the cell voltage data is obtained; the cell voltage data is data collected when the battery is in a static state;

[0027] Get the relationship curve between battery SOC and voltage;

[0028] According to the cell voltage data and in combination with the relationship curve between the SOC and voltage of the battery, it is determined whether the voltage acquisition function of the analog front-end chip is abnormal.

[0029] In the voltage and temperature detection method for a battery management system according to the present invention, determining whether the voltage acquisition function of the analog front-end chip is abnormal based on the cell voltage data and a curve of the relationship between the battery's SOC and voltage includes:

[0030] Obtaining, according to the battery cell voltage data, a voltage value corresponding to the battery cell voltage data in a relationship curve between the SOC and voltage of the battery;

[0031] Comparing the cell voltage data with the voltage value to obtain a voltage deviation value between the cell voltage data and the voltage value;

[0032] Determining whether the voltage deviation value is greater than or equal to a first deviation threshold;

[0033] If so, it is determined that the voltage acquisition function of the analog front-end chip is abnormal;

[0034] If not, it is determined whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery.

[0035] In the voltage and temperature detection method for a battery management system according to the present invention, determining whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery includes:

[0036] Acquire a first cell voltage of a first cell of the battery through a voltage acquisition port of the analog front-end chip;

[0037] Obtaining the second cell voltage of the first cell through the GPIO port of the analog front-end chip;

[0038] Determining whether the first cell voltage is equal to the second cell voltage and whether the first cell voltage is within a preset voltage range;

[0039] If the first cell voltage is equal to the second cell voltage and the first cell voltage is within a preset voltage range, it is determined that the first cell voltage acquisition function of the analog front-end chip is normal; otherwise, it is determined that the first cell voltage acquisition function of the analog front-end chip is abnormal.

[0040] In the voltage and temperature detection method for a battery management system according to the present invention, judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery further comprises:

[0041] If the first cell voltage acquisition function of the analog front-end chip is normal, acquiring the cell voltages of the remaining cells of the battery;

[0042] Comparing the cell voltages of the remaining cells with the first cell voltage to obtain a cell deviation value corresponding to the cell voltage of each cell in the remaining cells and the first cell voltage;

[0043] Determine whether a cell deviation value between the cell voltage of each cell and the first cell voltage is less than or equal to a second deviation threshold; if so, determine that the voltage acquisition functions of other cells of the analog front-end chip are normal;

[0044] If any one or more of the cell deviation values ​​between the cell voltage of each cell and the first cell voltage is greater than the second deviation threshold, performing balancing processing;

[0045] After the equalization process reaches a preset time period, continue to determine whether the cell voltage of each single cell and the cell deviation value corresponding to the first cell voltage is less than or equal to a second deviation threshold value; if so, determine that the voltage acquisition function of the remaining cells of the analog front-end chip is normal;

[0046] If after the equalization processing reaches a preset time period, the single deviation value is still greater than the second deviation threshold, then it is determined whether each single deviation value greater than the second deviation threshold is continuously greater than the second deviation threshold. If so, it is determined that the voltage acquisition function of the analog front-end chip is abnormal or the voltage is uneven.

[0047] In the voltage and temperature detection method for a battery management system according to the present invention, the switch unit includes a multiplexer switch; the multiplexer switch includes N temperature acquisition channels; N is an integer greater than or equal to 2; the transmitted temperature information includes N temperature data transmitted by the N acquisition channels; the acquired temperature information is a temperature value acquired through a GPIO port of an analog front-end chip;

[0048] The detecting whether the temperature acquisition function of the switch unit is abnormal based on the acquired temperature information and the transmitted temperature information, and if abnormal, outputting abnormal alarm information of the temperature acquisition function of the switch unit includes:

[0049] Acquire a first temperature value of a first channel among the N temperature acquisition channels;

[0050] Comparing the first temperature value with the collected temperature value;

[0051] If the first temperature value is equal to the collected temperature value, it is determined that the first channel is normal; otherwise, an abnormal alarm message indicating that the temperature collection function of the first channel of the multiplexing switch is abnormal is output.

[0052] In the voltage and temperature detection method for a battery management system according to the present invention, detecting whether the temperature acquisition function of the switch unit is abnormal based on the acquired temperature information and the transmitted temperature information, and if abnormal, outputting abnormal alarm information of the temperature acquisition function of the switch unit further includes:

[0053] If the first temperature value is equal to the collected temperature value, then the remaining N-1 temperature data of the N temperature data are compared with the first temperature value respectively;

[0054] If the N-1 temperature data are all equal to the first temperature value, it is determined that the temperature acquisition function of the N-1 channels corresponding to the multiplexing switch and the N-1 temperature data is normal; otherwise, it is determined that the temperature acquisition function of the corresponding channel is abnormal and an alarm message is output.

[0055] The present invention further provides a battery management system, comprising: a voltage acquisition unit, a switch unit connected to the voltage acquisition unit, and a control unit connected to the voltage acquisition unit and the switch unit; the control unit is configured to:

[0056] Acquiring voltage information and temperature information from the voltage acquisition unit;

[0057] acquiring transmission temperature information of the switch unit;

[0058] detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information, and outputting abnormal alarm information of the voltage acquisition function of the voltage acquisition unit if abnormal;

[0059] Based on the collected temperature information and the transmitted temperature information, it is detected whether the temperature collection function of the switch unit is abnormal. If abnormal, abnormal alarm information of the temperature collection function of the switch unit is output.

[0060] The present invention also provides an electronic device including the above-mentioned battery management system.

[0061] The battery management system, voltage and temperature detection method, and electronic device implementing the present invention have the following beneficial effects: comprising: a voltage acquisition unit and a switch unit connected to the voltage acquisition unit; the method comprising: obtaining voltage information and collected temperature information from the voltage acquisition unit; obtaining transmission temperature information from the switch unit; detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information; and if so, outputting a voltage acquisition function abnormality alarm; detecting whether the temperature acquisition function of the switch unit is abnormal based on the collected temperature information and the transmission temperature information; and if so, outputting a temperature acquisition function abnormality alarm. The present invention can detect the voltage and temperature detection functions of the battery management system and provide a warning of functional abnormalities, meeting functional safety requirements, and can be implemented without adding redundant chips, significantly reducing costs and effectively reducing product size pressures. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0063] Figure 1 Schematic diagram of the battery management system provided by an embodiment of the present invention;

[0064] Figure 2 is a schematic diagram of a battery management system provided by an embodiment of the present invention;

[0065] Figure 3 1 is a flow chart of a first embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0066] Figure 4 1 is a flow chart of a second embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0067] Figure 5 1 is a flow chart of a third embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0068] Figure 6 1 is a flow chart of a fourth embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0069] Figure 7 1 is a flow chart of a fifth embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0070] Figure 8 1 is a flow chart of a sixth embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0071] Figure 9 1 is a flow chart of a seventh embodiment of a voltage and temperature detection method for a battery management system provided by the present invention;

[0072] Figure 10 4 is a flow chart of an eighth embodiment of a voltage and temperature detection method for a battery management system provided by the present invention. DETAILED DESCRIPTION

[0073] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0074] Specifically, such as Figure 1 FIG2 shows a battery management system provided by the present invention, which includes a voltage acquisition unit 10 , a switch unit 20 connected to the voltage acquisition unit 10 , and a control unit 30 connected to the voltage acquisition unit 10 and the switch unit 20 .

[0075] The voltage acquisition unit 10 is used to acquire and monitor the voltage of the battery. The switch unit 20 is used to obtain temperature information output by the temperature sensor 40 under the control of the control unit 30 and transmit the temperature information to the voltage acquisition unit 10 .

[0076] The control unit 30 is used to: obtain voltage information and collected temperature information of the voltage collection unit 10; obtain transmission temperature information of the switch unit 20; detect whether the voltage collection function of the voltage collection unit 10 is abnormal based on the voltage information, and if so, output abnormal alarm information of the voltage collection function of the voltage collection unit 10; detect whether the temperature collection function of the switch unit 20 is abnormal based on the collected temperature information and the transmitted temperature information, and if so, output abnormal alarm information of the temperature collection function of the switch unit 20.

[0077] Optionally, in an embodiment of the present invention, the voltage acquisition unit 10 may include an analog front-end chip, and the switch unit 20 may include a multiplexer switch. In this embodiment of the present invention, the voltage acquisition unit 10 only requires one analog front-end chip and one multiplexer switch to meet functional safety requirements.

[0078] In the embodiment of the present invention, by detecting the voltage information and the collected temperature information of the voltage acquisition unit 10 and the transmitted temperature information of the switch unit 20 and adopting the corresponding preset voltage detection method and preset channel detection method, the voltage acquisition function of the voltage acquisition unit 10 and the channel transmission function of the switch unit 20 can be detected, thereby realizing monitoring and early warning of abnormal voltage or temperature acquisition conditions, and outputting corresponding abnormal alarm information in time when functional abnormalities occur, thereby achieving the purpose of meeting functional safety requirements without the need for a dual-chip structure, effectively reducing costs, and greatly reducing product size pressure.

[0079] In a specific embodiment, Figure 2, which is a schematic diagram of the battery management system provided by the present invention.

[0080] like Figure 2 As shown, in this embodiment, the analog front-end chip includes nine GPIO ports (GPIO1 to GPIO9), a reference source port, and n voltage acquisition ports (VC1 to VCn). The battery includes n series-connected cells (B1 to Bn). VC1 to VCn correspond to cells B1 to Bn and are used to acquire the voltages of the cells B1 to Bn. Optionally, in this embodiment of the present invention, the GPIO ports of the analog front-end chip can function as both IO ports and AD ports.

[0081] like Figure 2 As shown, one end of the multiplexing switch (here the multiplexing switch is an IC) is connected to the GPIO corresponding to the analog front-end chip, and the other end is connected to the output port corresponding to the temperature sensor 40 through the channel switch. Figure 2 As shown, the temperature sensor 40 includes temperature output ports T1 to T8. Correspondingly, the multiplexing switch has 8 temperature acquisition ports. Each temperature acquisition port corresponds to a temperature acquisition channel. Each channel controls the on-off between the multiplexing switch and the temperature sensor 40 through a switch.

[0082] Specifically, such as Figure 2 As shown, the first channel is connected to the T1 temperature output port of the temperature sensor 40 through the first switch S1, and the first channel is also directly connected to the GPIO2 port of the analog front-end chip, the second channel is connected to the T2 temperature output port of the temperature sensor 40 through the ninth switch S9, the third channel is connected to the T3 temperature output port of the temperature sensor 40 through the tenth switch S10, the fourth channel is connected to the T4 temperature output port of the temperature sensor 40 through the eleventh switch S11, the fifth channel is connected to the T5 temperature output port of the temperature sensor 40 through the twelfth switch S12, the sixth channel is connected to the T6 temperature output port of the temperature sensor 40 through the thirteenth switch S13, the seventh channel is connected to the T7 temperature output port of the temperature sensor 40 through the fourteenth switch S14, and the eighth channel is connected to the T8 temperature output port of the temperature sensor 40 through the fifteenth switch S15.

[0083] By adopting the voltage temperature detection method of the present invention, it is possible to detect the voltage acquisition function of the analog front-end chip and the temperature acquisition function of the multiplex switch.

[0084] Specifically, such as Figure 3 FIG. 1 is a flow chart of an optional embodiment of a voltage and temperature detection method for a battery management system provided by the present invention.

[0085] like Figure 3As shown, in this embodiment, the voltage and temperature detection method of the battery management system includes the following steps:

[0086] Step S301: Acquire voltage information and temperature information from the voltage acquisition unit 10.

[0087] Optionally, in an embodiment of the present invention, the voltage information includes: power supply information of the analog front-end chip and battery cell voltage data.

[0088] Step S302 : Acquire the transmission temperature information of the switch unit 20 .

[0089] Step S303: Based on the voltage information, the voltage acquisition function of the voltage acquisition unit 10 is detected to determine whether it is abnormal. If so, an abnormality alarm message is outputted indicating that the voltage acquisition function of the voltage acquisition unit 10 is abnormal. Optionally, in this embodiment of the present invention, based on the voltage information and using a preset voltage detection method, the voltage acquisition function of the voltage acquisition unit 10 is detected to determine whether it is abnormal. If so, an abnormality alarm message is outputted indicating that the voltage acquisition function of the voltage acquisition unit 10 is abnormal.

[0090] Step S304: Based on the collected temperature information and the transmitted temperature information, it is detected whether the temperature collection function of the switch unit 20 is abnormal. If abnormal, an abnormal alarm message of the temperature collection function of the switch unit 20 is output.

[0091] Optionally, in an embodiment of the present invention, based on the collected temperature information and the transmitted temperature information and using a preset channel detection method, it is detected whether the temperature collection function of the switch unit 20 is abnormal. If abnormal, an abnormal alarm information of the temperature collection function of the switch unit 20 is output.

[0092] It should be noted that, in the embodiment of the present invention, there is no order requirement for step S301 and step S302, and step S303 and step S304, and they can be executed sequentially or in parallel, and the present invention does not impose any specific limitation on this.

[0093] Furthermore, in an embodiment of the present invention, before the voltage acquisition unit 10 acquires voltage information, it is first determined whether the communication between the analog front-end chip and the control unit 30 is normal. If abnormal, a communication fault alarm is output; if normal, voltage information acquisition is performed.

[0094] Specifically, in some embodiments, Figure 4 As shown, based on the voltage information and using a preset voltage detection method, the voltage acquisition function of the voltage acquisition unit 10 is detected to see if it is abnormal. If it is abnormal, the abnormal alarm information of the voltage acquisition function of the output voltage acquisition unit 10 includes:

[0095] Step S401: Determine whether the power supply function of the analog front-end chip is normal according to the power supply information.

[0096] Step S402: If the power supply function of the analog front-end chip is abnormal, output analog front-end chip power supply abnormality alarm information.

[0097] Step S403: If the power supply function of the analog front-end chip is normal, determine whether the voltage acquisition function of the analog front-end chip is abnormal based on the cell voltage data.

[0098] Step S404: If the voltage acquisition function of the analog front-end chip is abnormal, outputting alarm information of the voltage acquisition function of the analog front-end chip.

[0099] Specifically, in some embodiments, Figure 5 As shown, judging whether the power supply function of the analog front-end chip is normal based on the power supply information includes:

[0100] Step S501: Acquire a reference value of a reference source of an analog front-end chip.

[0101] Specifically, in the embodiment of the present invention, the reference value of the reference source of the analog front-end chip is a known fixed value and can be pre-stored in the memory of the analog front-end chip.

[0102] Step S502: Divide the reference value of the reference source to obtain a divided voltage value.

[0103] Specifically, such as Figure 2 As shown, the reference value of the reference source can be obtained by dividing the voltage of a voltage divider circuit 50 provided between the reference source port of the analog front-end chip and the GPIO9 port. The voltage divider circuit 50 includes a first resistor R1 and a second resistor R2 connected in series.

[0104] Step S503: input the voltage division value into the voltage division input port of the analog front-end chip.

[0105] Step S504: Obtain the voltage division value through the voltage division input port.

[0106] Step S505 : judging whether the power supply function of the analog front-end chip is normal according to the voltage division value and the reference value of the reference source.

[0107] In an embodiment of the present invention, judging whether the power supply function of the analog front-end chip is normal based on the voltage divider value and the reference value of the reference source includes: comparing the voltage divider value with the reference value of the reference source; if the voltage divider value is equal to the reference value of the reference source and the voltage divider value is within a preset voltage range, then judging that the power supply function of the analog front-end chip is normal, otherwise judging that the power supply function of the analog front-end chip is abnormal.

[0108] Optionally, the preset voltage range may be 4.5 to 5.5V.

[0109] Specifically, in some embodiments, Figure 6As shown, if the power supply function of the analog front-end chip is normal, then judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the cell voltage data includes:

[0110] Step S601: If the power supply function of the analog front-end chip is normal, obtain the cell voltage data; the cell voltage data is data collected when the battery is in a static state.

[0111] Step S602: Obtain a curve showing the relationship between the battery's SOC and voltage.

[0112] Step S603: judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the cell voltage data and the relationship curve between the battery's SOC and voltage.

[0113] Specifically, in some embodiments, Figure 7 As shown, based on the cell voltage data and the relationship curve between the battery's SOC and voltage, it is determined whether the voltage acquisition function of the analog front-end chip is abnormal. The following are included:

[0114] Step S701: Obtain, according to the cell voltage data, a voltage value corresponding to the cell voltage data in a curve of the relationship between the SOC and voltage of the battery.

[0115] Optionally, in an embodiment of the present invention, a battery SOC-voltage curve can be calculated based on the battery's charge-discharge curve. This SOC-voltage curve can be pre-stored in the control unit 30 as an initial curve. As the battery ages, this SOC-voltage curve will change, and can be dynamically modified by the control unit 30. The corresponding values ​​of this SOC-voltage curve are shown in the following table.

[0116] Capacity percentage % Battery voltage V 100 4.2 90 4.08 80 4 70 3.93 60 3.87 50 3.82 40 3.79 30 3.77 20 3.73 15 3.7 10 3.68 5 3.5 0 2.5

[0117] It should be noted that the voltage values ​​in the above table are not fixed, but are dynamically adjusted as the battery is used.

[0118] Step S702: Compare the cell voltage data with the voltage value to obtain a voltage deviation value between the cell voltage data and the voltage value.

[0119] Step S703: Determine whether the voltage deviation value is greater than or equal to a first deviation threshold.

[0120] Optionally, in an embodiment of the present invention, the first deviation threshold may be 0.5V.

[0121] Step S704: If yes, determine that the voltage acquisition function of the analog front-end chip is abnormal.

[0122] Step S705: If not, determine whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery.

[0123] Specifically, in some embodiments, Figure 8 As shown, judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the single-cell voltage data of the battery includes:

[0124] Step S801: Acquire a first cell voltage of a first cell of a battery through a voltage acquisition port of an analog front-end chip.

[0125] Step S802: Obtain the second cell voltage of the first cell through the GPIO port of the analog front-end chip.

[0126] Step S803: Determine whether the first cell voltage is equal to the second cell voltage, and whether the first cell voltage is within a preset voltage range.

[0127] Step S804: If the first cell voltage is equal to the second cell voltage and the first cell voltage is within the preset voltage range, it is determined that the first cell voltage acquisition function of the analog front-end chip is normal.

[0128] Step S805: Otherwise, it is determined that the voltage acquisition function of the first cell of the analog front-end chip is abnormal.

[0129] Specifically, in some embodiments, Figure 9 As shown, judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the single-cell voltage data of the battery also includes:

[0130] Step S901: If the first cell voltage acquisition function of the analog front-end chip is normal, the cell voltages of the remaining cells of the battery are acquired.

[0131] Step S902 : Compare the cell voltages of the remaining cells with the first cell voltage to obtain a cell deviation value corresponding to the cell voltage of each cell in the remaining cells and the first cell voltage.

[0132] Step S903 , determining whether the cell voltage of each single battery cell and the cell deviation value corresponding to the first cell voltage are less than or equal to the second deviation threshold; if so, determining that the remaining cell voltage acquisition functions of the analog front-end chip are normal.

[0133] Optionally, in an embodiment of the present invention, the second deviation threshold may be 0.2V.

[0134] Step S904 : If any one or more of the cell deviation values ​​corresponding to the cell voltage of each cell and the first cell voltage is greater than a second deviation threshold, perform balancing.

[0135] Step S905: After the equalization process reaches the preset time period, continue to determine whether the cell deviation value corresponding to the cell voltage of each single battery and the first cell voltage is less than or equal to the second deviation threshold; if so, determine that the remaining cell voltage acquisition functions of the analog front-end chip are normal.

[0136] Step S906: If there are still individual deviation values ​​greater than the second deviation threshold after the equalization process reaches the preset time period, it is determined whether each individual deviation value greater than the second deviation threshold continues to be greater than the second deviation threshold.

[0137] Step S907: If yes, determine that the voltage acquisition function of the analog front-end chip is abnormal or the voltage is uneven.

[0138] Specifically, in an embodiment of the present invention, whether each single deviation value greater than the second deviation threshold is continuously greater than the second deviation threshold means: for any single deviation value greater than the second deviation threshold, it is necessary to continue to continuously determine whether the single deviation values ​​within a preset number of times are all greater than the second deviation threshold; if the single deviation values ​​within a consecutive preset number of times are all greater than the second deviation threshold, it can be directly determined that the voltage acquisition function of the analog front-end chip is abnormal or the voltage is uneven.

[0139] Optionally, in an embodiment of the present invention, the switch unit 20 includes a multiplexing switch. The multiplexing switch includes N temperature acquisition channels, where N is an integer greater than or equal to 2. The transmitted temperature information includes N temperature data transmitted by the N acquisition channels. The collected temperature information is a collected temperature value collected via a GPIO port of the analog front-end chip.

[0140] Specifically, in some embodiments, Figure 10 As shown, based on the collected temperature information and the transmitted temperature information and using the preset channel detection method to detect whether the temperature collection function of the switch unit 20 is abnormal, if it is abnormal, the output temperature collection function abnormality alarm information of the switch unit 20 includes:

[0141] Step S110: Acquire a first temperature value of a first channel among N temperature acquisition channels.

[0142] Step S111: Compare the first temperature value with the collected temperature value.

[0143] Step S112: If the first temperature value is equal to the collected temperature value, it is determined that the first channel is normal.

[0144] Step S113: Otherwise, output the abnormal alarm information of the temperature acquisition function of the first channel of the multiplexing switch.

[0145] Furthermore, in an embodiment of the present invention, based on the collected temperature information and the transmitted temperature information and using a preset channel detection method, it is detected whether the temperature collection function of the switch unit 20 is abnormal. If abnormal, the output of the temperature collection function abnormal alarm information of the switch unit 20 also includes: if the first temperature value is equal to the collected temperature value, then the remaining N-1 temperature data in the N temperature data are compared with the first temperature value respectively for judgment; if the N-1 temperature data are all equal to the first temperature value, then it is judged that the temperature collection function of the N-1 channels corresponding to the multiplexing switch and the N-1 temperature data is normal; otherwise, it is judged that the temperature collection function of the corresponding channel is abnormal and an alarm message is output.

[0146] Optionally, in an embodiment of the present invention, the voltage and temperature detection method of the battery management system of the present invention can be performed during the power-on self-test, or can be performed after the charging and discharging is completed and the system is left to stand for 2 hours, or can be performed during the power-on self-test and after the charging and discharging is completed and the system is left to stand for 2 hours (that is, equivalent to self-checking the system once before charging and discharging, and once after charging and discharging).

[0147] Below Figure 2 The embodiment of the present invention describes in detail the voltage and temperature detection method of the battery management system.

[0148] Specifically, the control unit 30 is used to detect whether the communication with the analog front-end chip is normal. If abnormal, an analog front-end chip communication failure alarm is output. If normal, the power supply function of the analog front-end chip is then detected to see if it is normal. Get the reference source port ( Figure 2 The reference value of VREG in the analog front-end is set to V1, and the voltage of GPIO9 (i.e., the voltage divider value, set to V2) is collected at the same time to determine whether V2 is equal to V1 and whether the value of V2 is between 4.5 and 5.5V. If V2 = V1 and the value of V2 is between 4.5 and 5.5V, the power supply function of the analog front-end chip is determined to be normal. Otherwise, the power supply function of the analog front-end chip is determined to be abnormal and a power supply abnormality alarm message is output. It can be understood that if the power supply function of the analog front-end chip is determined to be abnormal, the voltage collection function is no longer tested, and the power supply abnormality alarm is directly output to maintain the system.

[0149] If the power supply function of the analog front-end chip is determined to be normal, it is necessary to further determine whether the voltage acquisition function of the analog front-end chip is abnormal. Specifically, when the battery is static, the battery cell voltage data is obtained and the voltage acquisition function of the analog front-end chip is determined to be abnormal based on the pre-stored battery SOC and voltage relationship curve.

[0150] Specifically, the SOC vs. voltage curve can be used to determine whether the cell voltage data read by the analog front-end chip is normal. This involves comparing the cell voltage data with the corresponding voltage value in the SOC vs. voltage curve to obtain a voltage deviation between the cell voltage data and the voltage value. The deviation is then determined to be greater than 0.5V. If so, the voltage acquisition function of the analog front-end chip is considered abnormal. If the deviation is less than 0.5V, further testing of the voltage acquisition function of the analog front-end chip is required to ensure accuracy.

[0151] For example, the SOC of a ternary lithium battery is about 50%. From the relationship curve between SOC and voltage, it can be seen that at this time, the corresponding cell voltage is about 3.82V. If the difference between the cell voltage data collected by the analog front-end chip and 3.82V is greater than 0.5V, it is judged that the voltage collection function of the analog front-end chip is abnormal. If the difference between the cell voltage data collected by the analog front-end chip and 3.82V is less than 0.5V, continue to perform the voltage collection function test.

[0152] Specifically, if the difference between the cell voltage data collected by the analog front-end chip and 3.82V is less than 0.5V, the first cell voltage (set as U1) of the first cell battery (B1) is collected through the VC1 port of the analog front-end chip, and the second cell voltage (set as U1) of the first cell battery (B1) is collected through the GPIO1 port of the analog front-end chip. GPIO1 ); Then, determine whether U1 is equal to U GPIO1 And the value of U1 is within 4.5~5.5V, if U1=U GPIO1 If the value of U1 is between 4.5 and 5.5, it is determined that the voltage acquisition function of the analog front-end chip for the first single battery is normal. Otherwise, it is determined that the voltage acquisition function of the analog front-end chip for the first single battery is abnormal, and an abnormal voltage acquisition function alarm message is output.

[0153] Furthermore, if the analog front-end chip is determined to be functioning properly in collecting the voltage of the first battery, the first cell voltage of the first battery is used as a reference for determining the voltage collection function of the remaining batteries B2 to Bn.

[0154] Specifically, the voltages of individual cells B2 through Bn (set as U2 through Un) are collected separately. These cells are then compared with U1 to obtain corresponding cell deviations (set as ΔU2 through ΔUn). A determination is then made as to whether ΔU2 through ΔUn are all less than 0.2V. If so, the analog front-end chip is deemed to be functioning properly in collecting voltages for each cell. If any one or more of ΔU2 through ΔUn are greater than 0.2V, equalization is performed, and monitoring resumes after a preset time period (the preset time period can be determined based on actual application).

[0155] For example, if △U2 is greater than 0.2V, the analog front-end chip will first perform equalization processing. After the equalization processing reaches a preset time period, U2 will continue to be obtained and compared with U1 to obtain △U2. It is determined whether △U2 is less than or equal to 0.2V at this time. If △U2 is less than 0.2V at this time, the analog front-end chip's voltage acquisition function for B2 is determined to be normal. If △U2 is greater than 0.2V at this time, the preset number of monitoring times (assuming 5 times) will be continuously monitored. If △U2 is greater than 0.2V for 5 consecutive times, it is determined that the analog front-end chip's voltage acquisition function for B2 is abnormal or the voltage is uneven. Similarly, the voltage acquisition function of other single cells is also tested using this method.

[0156] For the detection of the temperature acquisition function of the multiplex switch, in the present invention, as Figure 2 As shown, first collect Figure 2 The middle temperature sensor 40T1 directly transmits the temperature of the GPIO5 port of the analog front-end chip through S1 (set as t0), and the temperature of the first channel of the multiplexer switch through S1 (set as t1), and determines whether t0 and t1 are equal. If t0=t1, it can be determined that the temperature of the first channel of the multiplexer switch is normal and the temperature acquisition function of the first channel is normal. Otherwise, it is determined that the temperature acquisition function of the first channel is abnormal, and an alarm information indicating the abnormality of the temperature acquisition function of the multiplexer switch is output.

[0157] If t0=t1, then t1 is used as the reference temperature to determine the temperature of the second channel to the eighth channel. Figure 2 As shown, the ninth switch S9 to the fifteenth switch S15 are disconnected, and the first switch S1 is respectively turned to the contact S2 to the contact S8, and the read temperature values ​​t2 to t8 are respectively compared with t1. If all are equal to t1, it is determined that the temperature acquisition function of the second channel to the eighth channel is normal. If any one or more of t2 to t8 are not equal to t1, it is determined that the temperature acquisition function of the corresponding channel is abnormal, and the corresponding abnormal alarm information is output.

[0158] Furthermore, the present invention also provides an electronic device that may include the battery management system disclosed in the embodiments of the present invention. Optionally, the electronic device may be a household appliance (such as a microwave oven, coffee maker, or cooking machine), a battery, an industrial electrical product, an electric vehicle, etc.

[0159] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0160] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0161] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0162] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. All equivalent variations and modifications within the scope of the claims of the present invention are intended to be covered by the claims of the present invention.

Claims

1. A voltage and temperature detection method for a battery management system, characterized in that: The battery management system includes: a voltage acquisition unit and a switch unit connected to the voltage acquisition unit; the voltage acquisition unit includes: an analog front-end chip; the switch unit includes: a multiplexing switch; the multiplexing switch includes: N temperature acquisition channels; N is an integer greater than or equal to 2; the transmitted temperature information includes: N temperature data transmitted by the N acquisition channels; the collected temperature information is: the collected temperature value collected through the GPIO port of the analog front-end chip; The voltage temperature detection method comprises the following steps: Acquire voltage information and temperature information of the voltage acquisition unit; the voltage information includes: power supply information of the analog front-end chip and battery cell voltage data; acquiring transmission temperature information of the switch unit; Judging whether the power supply function of the analog front-end chip is normal according to the power supply information; if the power supply function of the analog front-end chip is abnormal, outputting abnormal power supply alarm information of the analog front-end chip; if the power supply function of the analog front-end chip is normal, judging whether the voltage acquisition function of the analog front-end chip is abnormal according to the battery cell voltage data; if the voltage acquisition function of the analog front-end chip is abnormal, outputting voltage acquisition function alarm information of the analog front-end chip; Obtain a first temperature value of a first channel among the N temperature acquisition channels; compare the first temperature value with the acquired temperature value; if the first temperature value is equal to the acquired temperature value, determine that the first channel is normal; otherwise, output an abnormal alarm message of the temperature acquisition function of the first channel of the multiplexing switch.

2. The voltage and temperature detection method for a battery management system according to claim 1, characterized in that: The determining, according to the power supply information, whether the power supply function of the analog front-end chip is normal includes: Obtaining a reference value of a reference source of the analog front-end chip; After dividing the reference value of the reference source, a divided voltage value is obtained; Inputting the divided voltage value into the divided voltage input port of the analog front-end chip; Obtaining the divided voltage value through the divided voltage input port; Whether the power supply function of the analog front-end chip is normal is judged according to the voltage division value and the reference value of the reference source.

3. The voltage and temperature detection method for a battery management system according to claim 2, characterized in that: The determining, based on the voltage division value and the reference value of the reference source, whether the power supply function of the analog front-end chip is normal includes: Comparing the voltage division value with the reference value of the reference source; If the voltage division value is equal to the reference value of the reference source and the voltage division value is within a preset voltage range, it is determined that the power supply function of the analog front-end chip is normal; otherwise, it is determined that the power supply function of the analog front-end chip is abnormal.

4. The voltage and temperature detection method for a battery management system according to claim 1, wherein: If the power supply function of the analog front-end chip is normal, determining whether the voltage acquisition function of the analog front-end chip is abnormal according to the cell voltage data includes: If the power supply function of the analog front-end chip is normal, the cell voltage data is obtained; the cell voltage data is data collected when the battery is in a static state; Get the relationship curve between battery SOC and voltage; According to the cell voltage data and in combination with the relationship curve between the SOC and voltage of the battery, it is determined whether the voltage acquisition function of the analog front-end chip is abnormal.

5. The voltage and temperature detection method for a battery management system according to claim 4, characterized in that: The determining whether the voltage acquisition function of the analog front-end chip is abnormal based on the cell voltage data and in combination with the relationship curve between the SOC and voltage of the battery includes: Obtaining, according to the battery cell voltage data, a voltage value corresponding to the battery cell voltage data in a relationship curve between the SOC and voltage of the battery; Comparing the cell voltage data with the voltage value to obtain a voltage deviation value between the cell voltage data and the voltage value; Determining whether the voltage deviation value is greater than or equal to a first deviation threshold; If so, it is determined that the voltage acquisition function of the analog front-end chip is abnormal; If not, it is determined whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery.

6. The voltage and temperature detection method for a battery management system according to claim 5, characterized in that: The determining whether the voltage acquisition function of the analog front-end chip is abnormal according to the single cell voltage data of the battery includes: Acquire a first cell voltage of a first cell of the battery through a voltage acquisition port of the analog front-end chip; Obtaining the second cell voltage of the first cell through the GPIO port of the analog front-end chip; Determining whether the first cell voltage is equal to the second cell voltage and whether the first cell voltage is within a preset voltage range; If the first cell voltage is equal to the second cell voltage and the first cell voltage is within a preset voltage range, it is determined that the first cell voltage acquisition function of the analog front-end chip is normal; otherwise, it is determined that the first cell voltage acquisition function of the analog front-end chip is abnormal.

7. The voltage and temperature detection method for a battery management system according to claim 6, characterized in that: The determining whether the voltage acquisition function of the analog front-end chip is abnormal based on the single cell voltage data of the battery further includes: If the first cell voltage acquisition function of the analog front-end chip is normal, acquiring the cell voltages of the remaining cells of the battery; Comparing the cell voltages of the remaining cells with the first cell voltage to obtain a cell deviation value corresponding to the cell voltage of each cell in the remaining cells and the first cell voltage; Determine whether a cell deviation value between the cell voltage of each cell and the first cell voltage is less than or equal to a second deviation threshold; if so, determine that the voltage acquisition functions of other cells of the analog front-end chip are normal; If any one or more of the cell deviation values ​​between the cell voltage of each cell and the first cell voltage is greater than the second deviation threshold, performing balancing processing; After the equalization process reaches a preset time period, continue to determine whether the cell voltage of each single cell and the cell deviation value corresponding to the first cell voltage is less than or equal to a second deviation threshold value; if so, determine that the voltage acquisition function of the remaining cells of the analog front-end chip is normal; If after the equalization processing reaches a preset time period, the single deviation value is still greater than the second deviation threshold, then it is determined whether each single deviation value greater than the second deviation threshold is continuously greater than the second deviation threshold. If so, it is determined that the voltage acquisition function of the analog front-end chip is abnormal or the voltage is uneven.

8. The voltage and temperature detection method for a battery management system according to claim 1, characterized in that: Detecting whether the temperature acquisition function of the switch unit is abnormal based on the acquired temperature information and the transmitted temperature information, and if abnormal, outputting abnormal alarm information of the temperature acquisition function of the switch unit further includes: If the first temperature value is equal to the collected temperature value, then the remaining N-1 temperature data of the N temperature data are compared with the first temperature value respectively; If the N-1 temperature data are all equal to the first temperature value, it is determined that the temperature acquisition function of the N-1 channels corresponding to the multiplexing switch and the N-1 temperature data is normal; otherwise, it is determined that the temperature acquisition function of the corresponding channel is abnormal and an alarm message is output.

9. A battery management system, characterized in that: include: A voltage acquisition unit, a switch unit connected to the voltage acquisition unit, and a control unit connected to the voltage acquisition unit and the switch unit; The voltage acquisition unit includes: an analog front-end chip; the switch unit includes: a multiplexing switch; the multiplexing switch includes: N temperature acquisition channels; N is an integer greater than or equal to 2; the transmitted temperature information includes: N temperature data transmitted by the N acquisition channels; the collected temperature information is: the collected temperature value collected through the GPIO port of the analog front-end chip; the control unit is used to: Acquire voltage information and temperature information of the voltage acquisition unit; the voltage information includes: power supply information of the analog front-end chip and battery cell voltage data; acquiring transmission temperature information of the switch unit; Detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information, and if so, outputting abnormal alarm information of the voltage acquisition function of the voltage acquisition unit; detecting whether the voltage acquisition function of the voltage acquisition unit is abnormal based on the voltage information, and if so, outputting abnormal alarm information of the voltage acquisition function of the voltage acquisition unit includes: judging whether the power supply function of the analog front-end chip is normal based on the power supply information; if the power supply function of the analog front-end chip is abnormal, outputting abnormal power supply alarm information of the analog front-end chip; if the power supply function of the analog front-end chip is normal, judging whether the voltage acquisition function of the analog front-end chip is abnormal based on the battery cell voltage data; if the voltage acquisition function of the analog front-end chip is abnormal, outputting abnormal alarm information of the voltage acquisition function of the analog front-end chip; detecting whether the temperature acquisition function of the switch unit is abnormal based on the acquired temperature information and the transmitted temperature information, and outputting abnormal alarm information of the temperature acquisition function of the switch unit if abnormal; Detecting whether the temperature acquisition function of the switch unit is abnormal based on the acquired temperature information and the transmitted temperature information, and if abnormal, outputting abnormal alarm information of the temperature acquisition function of the switch unit includes: obtaining a first temperature value of a first channel among the N temperature acquisition channels; comparing the first temperature value with the acquired temperature value; if the first temperature value is equal to the acquired temperature value, determining that the first channel is normal; otherwise, outputting abnormal alarm information of the temperature acquisition function of the first channel of the multiplexing switch.

10. An electronic device, characterized in that: Including the battery management system according to claim 9.

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