Partitioned thermal management battery system

Abstract

The present invention discloses a zoned thermal management battery system, comprising: a plurality of battery boxes arranged at different positions of a vehicle, wherein a plurality of single cells connected in series are arranged in the battery box; a heating circuit arranged in the battery box, wherein the heating circuit comprises a heating plate connected in series and a switch in the box, wherein the heating plate is used to heat the plurality of single cells connected in series; a temperature acquisition unit arranged in the battery box, wherein the heating circuit is used to acquire temperature information in the battery box; a main switch arranged outside the battery box, wherein the heating circuit is connected in parallel with the plurality of single cells connected in series through the main switch; and a main control module connected with the switch in the box, the temperature acquisition unit and the main switch, wherein the main control module is used to control the heating speed of the heating circuit according to the temperature information in each battery box, and adjust the single cells in different battery boxes to work within a preset working temperature range, thereby realizing zoned thermal management. The temperature consistency of the battery system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery heating control, and more specifically, to a zoned thermal management battery system. Background Art

[0002] With the improvement of technical indicators of new energy vehicles, the requirements for vehicle range are further increased, and the matching power is further increased. More and more battery boxes are arranged in different positions of the vehicle. The difference in ambient temperature at different positions leads to an increase in the temperature difference inside the battery system, which in turn leads to a decrease in the availability and performance of the battery system.

[0003] At the same time, in the manufacturing process, due to the resistance error of the heating plate, the loose connection of the electrical connection, and the jamming of the switching device, the temperature difference inside the battery system will also increase, and more seriously, it will cause safety problems in the battery system.

[0004] In view of this, there is an urgent need to provide a partitionable thermal management battery system to solve the temperature difference problem of the battery system and avoid the occurrence of battery system safety problems. Summary of the invention

[0005] The purpose of the present invention is to propose a zoned thermal management battery system to achieve zoned thermal management of multiple battery boxes at different positions on a vehicle and improve the temperature consistency of the battery system.

[0006] To achieve the above objectives, the present invention proposes a partitioned thermal management battery system, comprising:

[0007] A plurality of battery boxes are arranged at different positions of the vehicle, wherein a plurality of single cells connected in series are arranged in the battery boxes;

[0008] A heating circuit is arranged in the battery box, the heating circuit comprises a heating plate connected in series and a switch in the box, the heating plate is used to heat the plurality of single cells connected in series;

[0009] A temperature collection unit is disposed in the battery box and is used to collect temperature information in the battery box;

[0010] A main switch is arranged outside the battery box, and the heating circuit is connected in parallel with the plurality of single cells connected in series through the main switch;

[0011] The main control module is connected to the switch in the box, the temperature acquisition unit and the main switch. The main control module is used to control the heating speed of the heating circuit according to the temperature information in each battery box, adjust the single cells in different battery boxes to work within a preset working temperature range, and realize zoned thermal management.

[0012] Optionally, the heating circuit further includes an ammeter and a voltmeter, the ammeter is connected in series with the heating plate and the switch in the box, and the voltmeter is connected in parallel with the heating plate; the ammeter and the voltmeter are respectively connected to the main control module;

[0013] The ammeter is used to collect current information of the heating circuit, and the voltmeter is used to collect voltage information at both ends of the heating plate.

[0014] Optionally, the main control module calculates the resistance information of the heating plate in each battery box according to the current information and the voltage information, and outputs differentiated PWM control switch instructions to the switches in different battery boxes according to the resistance information and the temperature information, thereby controlling the heating plates in different battery boxes to operate at different heating speeds, so that the single cells in different battery boxes all operate within a preset operating temperature range, thereby realizing zoned thermal management.

[0015] Optionally, the main control module is further used to diagnose whether the resistance of the heating plate exceeds a preset resistance range or is broken according to the resistance information of the heating plate and the control switch command.

[0016] Optionally, it also includes a first total voltmeter and a second total voltmeter, the first total voltmeter is connected in parallel with both ends of the multiple single cells connected in series, the second total voltmeter is connected in parallel with the heating circuit, and is simultaneously connected in parallel with both ends of the multiple single cells connected in series through the main switch.

[0017] Optionally, the main control module is further used to diagnose whether the main switch is in a stuck state according to a control switch command and voltage information collected by the first total voltmeter and the second total voltmeter.

[0018] Optionally, the main switch and the switch in the box are the same or different switch devices, and the switch devices include IGBT switches, MOSFET switches, SIC switches and relays.

[0019] Optionally, the heating sheet is attached to the surface of the plurality of single cells connected in series, and the heating sheet is formed by one of a resistance wire, a PTC heating element, and a graphene heating film.

[0020] Optionally, the ammeter is a Hall sensor or a shunt.

[0021] Optionally, the voltmeter, the first total voltmeter and the second total voltmeter all include a series resistor voltage divider circuit and an A / D conversion module.

[0022] The beneficial effects of the present invention are:

[0023] By setting a temperature meter in each battery box to collect the real-time temperature information of the single battery, the main control module controls the heating speed of the heating circuit according to the temperature information in each battery box, adjusts the single batteries in different battery boxes to work within the preset working temperature range, improves the temperature consistency of the battery system, and realizes zoned thermal management, which can effectively solve the temperature difference problem of the battery system caused by inconsistent distribution space of the battery boxes in the prior art.

[0024] Furthermore, the main control module realizes heating circuit diagnosis and main switch stuck status diagnosis according to battery system status information such as control switch commands, heating circuit current and voltage information, and total voltage information, which can effectively avoid secondary disasters and reduce the difficulty of fault diagnosis.

[0025] The device of the present invention has other characteristics and advantages, which will be obvious from the drawings incorporated herein and the following detailed description, or will be described in detail in the drawings incorporated herein and the following detailed description, which together are used to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which like reference numerals generally represent like components.

[0027] Figure 1 A circuit diagram of a zoned thermal management battery system according to an embodiment of the present invention is shown.

[0028] Figure 2 A schematic diagram of a main control module in a zoned thermal management battery system according to an embodiment of the present invention is shown.

[0029] Figure 3 A circuit diagram of a partitioned thermal management battery system according to a specific application example of the present invention is shown. DETAILED DESCRIPTION

[0030] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0031] Figure 1 A circuit diagram of a zoned thermal management battery system according to an embodiment of the present invention is shown.

[0032] like Figure 1As shown, a partitioned thermal management battery system includes:

[0033] A plurality of battery boxes are arranged at different positions of the vehicle, wherein a plurality of single cells connected in series are arranged in the battery boxes;

[0034] A heating circuit is arranged in the battery box, the heating circuit comprises a heating plate connected in series and a switch in the box, the heating plate is used to heat a plurality of single cells connected in series;

[0035] A temperature collection unit is disposed in the battery box and is used to collect temperature information in the battery box;

[0036] A main switch is arranged outside the battery box, and the heating circuit is connected in parallel with a plurality of series-connected single batteries through the main switch;

[0037] The main control module is connected to the switch in the box, the temperature acquisition unit, and the main switch. The main control module is used to control the heating speed of the heating circuit according to the temperature information in each battery box, adjust the single cells in different battery boxes to work within the preset working temperature range, and realize zoned thermal management.

[0038] Specifically, the main control module performs calculations based on the status information of each battery box and the most suitable operating temperature range of the battery system, controls the heating speed of the heating circuits in different battery boxes, and quickly heats the battery boxes operating outside the preset operating temperature range to within the preset operating temperature range, so that the temperature difference of multiple battery boxes is within the preset range, thereby completing zoned thermal management.

[0039] like Figure 1 As shown, when the main switch is in the closed state, when the switch in any battery box is closed, the two ends of the multiple series-connected single batteries in the corresponding battery box are connected to the heating circuit, the battery supplies power to the heating circuit, and the heating plate achieves heating. In order to control the heating speed of the heating circuit, it is preferred to control the frequency modulation of the switch in the box through PWM control switch instructions, thereby achieving frequency modulation control of the heating speed of each battery box. In this embodiment, the switch in the box is preferably an IGBT switch, and the main switch is a relay. In other embodiments, the switch in the box can also be a MOSFET switch, a SIC switch or a relay, and the main switch can also be an IGBT switch, a MOSFET switch or a SIC switch.

[0040] Furthermore, in this embodiment, the heating circuit also includes an ammeter and a voltmeter, the ammeter is connected in series with the heating plate and the switch in the box, and the voltmeter is connected in parallel with the heating plate; the ammeter and the voltmeter are respectively connected to the main control module;

[0041] The ammeter is used to collect the current information of the heating circuit, and the voltmeter is used to collect the voltage information at both ends of the heating plate.

[0042] The main control module calculates the resistance information of the heating plate in each battery box based on the current information and voltage information, and outputs differentiated PWM control switch instructions to the switches in different battery boxes based on the resistance information and temperature information, thereby controlling the heating plates in different battery boxes to operate at different heating speeds, so that the single cells in different battery boxes all operate within the preset operating temperature range, realizing zoned thermal management.

[0043] Specifically, the voltage meter, ammeter and temperature meter inside the battery box transmit the corresponding voltage, current and temperature information to the main control module; the main control module calculates the resistance of the heating plate inside each battery box according to the voltage meter and ammeter readings of each battery box; the main control module calculates the average temperature of each battery box according to the temperature meter of each battery box; the main control module performs calculations based on the resistance value, average temperature and most suitable working temperature range of the heating plate of each battery box, outputs differentiated PWM instructions to the internal switch of each battery box, and completes the zoned thermal management. According to the resistance value and real-time temperature, the heating speed can be controlled more accurately.

[0044] In this embodiment, the main control module is also used to diagnose whether the resistance of the heating plate exceeds a preset resistance range or is broken according to the resistance information of the heating plate and the control switch command.

[0045] Specifically, the main control module completes the diagnosis of whether the resistance of the heating plate is within its error range and the heating circuit short circuit diagnosis based on the resistance of each battery box heating plate, the voltmeter reading, and the control switch command output to the battery box, and executes the control strategy according to the diagnosis results.

[0046] In this embodiment, a first total voltmeter and a second total voltmeter are also included. The first total voltmeter is connected in parallel with both ends of a plurality of single cells connected in series, and the second total voltmeter is connected in parallel with the heating circuit and connected in parallel with both ends of a plurality of single cells connected in series through a main switch.

[0047] The main control module is also used to diagnose whether the main switch is in a stuck state according to the control switch command and the voltage information collected by the first main voltmeter and the second main voltmeter.

[0048] Specifically, the main control module completes the switch stuck open diagnosis or the switch stuck closed diagnosis according to the resistance value of each battery box heating plate, the voltmeter reading, and the control switch command output to the battery box.

[0049] In this embodiment, the heating sheet is attached to the surface of a plurality of single cells connected in series, and the heating sheet is composed of a resistance wire. In other embodiments, the heating sheet may also be composed of a PTC heating element or a graphene heating film.

[0050] In this embodiment, the ammeter is a Hall sensor, and in other embodiments, the ammeter may also be a shunt, etc. The voltmeter, the first total voltmeter, and the second total voltmeter all include a series resistor voltage divider circuit and an A / D conversion module, that is, a voltage divider formed by connecting multiple resistors in series and then connected in series with an analog quantity to digital quantity circuit.

[0051] refer to Figure 2 In this embodiment, the main control module has diagnostic and logic processing functions, and has a control port connected to the box switch, thermometer, ammeter, voltmeter and main switch, first main voltmeter and second main voltmeter in each battery box.

[0052] The present invention is further described below through specific application examples.

[0053] Application Example 1

[0054] like Figure 3 As shown, in this example, three battery boxes are provided at different positions on the vehicle, each battery box consists of 100 single cells connected in series, the total voltage of the 100 single cells connected in series is 330Vdc, and the switches in the three battery boxes are switch #1, switch #2, and switch #3 respectively. Set the average temperature of the batteries in the #1 battery box to 15°C, the average temperature of the batteries in the #2 battery box to 10°C, and the average temperature of the #3 battery box to 20°C. The target temperature range of heating is 24°C~26°C. If the state of the main switch control port of the main control module is closed, the main switch contact is closed, and the states of the control ports of the #1 switch, #2 switch, and #3 switch of the main control module are PWM control, then the main control module continuously adjusts the PWM of the control ports of the #1 switch, #2 switch, and #3 switch in a PID manner, wherein the #2 switch uses P (proportional) as the dominant, the #1 switch uses PD (proportional, differential) as the dominant, and the #3 switch uses I (integral) as the dominant. After 20 minutes, the average temperature of the batteries in the 1st box, the 2nd box, and the 3rd box all reach between 24°C and 26°C. At this point, the temperature distribution of the battery boxes tends to be consistent, thereby improving the performance of the battery system and extending the life of the battery system.

[0055] Application Example 2

[0056] In this example, there are 3 battery boxes in total, each battery box consists of 100 single cells connected in series, the total voltage of the 100 single cells connected in series is 330Vdc, the main contact state of the main switch is always set to closed, the main switch control port state of the main control module is open, and the diagnosis execution reads that the first total voltmeter is 330Vdc, and the total voltmeter 2 is 330Vdc, and the main contact of the main switch is diagnosed to be stuck in the closed state.

[0057] Application Example 3

[0058] In this example, there are 3 battery boxes in total, each battery box consists of 100 single cells connected in series, the total voltage of the 100 single cells connected in series is 330Vdc, the state of the main contacts of the main switch is always set to open, the state of the main switch control port of the main control module is closed, the diagnosis is executed and the first total voltmeter reads 330Vdc, the second total voltmeter reads 0Vdc, and the main contacts of the main switch are diagnosed to be stuck in the open state.

[0059] Application Example 4

[0060] In this example, there are 3 battery boxes in total, each of which consists of 100 single cells connected in series, and the total voltage of the 100 single cells connected in series is 330Vdc. The heating plate in battery box #1 is set to be open-circuited, the main switch control port state of the main control module is closed, the #1 switch control port state of the main control module is closed, and the working state of the main control module is the diagnostic state. The diagnosis is executed and the #1 voltmeter is read as 330Vdc and the #1 ammeter is 0A, and the first box of heating plate is diagnosed to be open-circuited.

[0061] Application Example 5

[0062] In this example, there are 3 battery boxes, each of which consists of 100 series-connected single cells, with a total voltage of 330Vdc. The resistance of the heater of battery box #1 is set to be out of tolerance (the nominal value range is between 26Ω and 40Ω, and the set value is 22Ω). The state of the main switch control port of the main control module is closed, the state of the #1 switch control port of the main control module is closed, and the working state of the main control module is the diagnostic state. The diagnostic execution reads 330Vdc on the #1 voltmeter and 15A on the #1 ammeter (the current value that should be read is between 8.25A and 12.7A), and it is diagnosed that the resistance of the heater of the first box is out of tolerance.

[0063] Application Example 6

[0064] In this example, there are 3 battery boxes, each of which consists of 100 series-connected cells, with a total voltage of 330Vdc. The resistance of the heater of battery box #1 is set to be out of tolerance (set to 44Ω), the main switch control port of the main control module is in closed state, the #1 switch control port of the main control module is in closed state, the main control module is in diagnostic state, and the #1 voltmeter is read as 330Vdc and the #1 ammeter is read as 7.5A (the current value should be between 8.25A and 12.7A), and the resistance of the heater of the first box is diagnosed to be out of tolerance.

[0065] Through application examples 1-6, it can be seen that the zoned thermal management battery system designed by the present invention can effectively improve the temperature consistency of the battery system during the operation of the battery system, and realize the diagnosis of the resistance difference of the heating plate, open circuit diagnosis and the stuck state of the main contacts of the main switch, which can effectively avoid the occurrence of secondary disasters and reduce the difficulty of fault judgment.

[0066] It should be noted that the PWM frequency modulation control of the heating speed of the heating circuit and the PID control method disclosed in the present invention are prior arts. At the same time, the control and diagnostic logic of the main control module in this application can be easily implemented by those skilled in the art through software programming, which will not be repeated here.

[0067] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A partitioned thermal management battery system, characterized in that: include: A plurality of battery boxes are arranged at different positions of the vehicle, wherein a plurality of single cells connected in series are arranged in the battery boxes; A heating circuit is arranged in the battery box, the heating circuit comprises a heating plate connected in series and a switch in the box, the heating plate is used to heat the plurality of single cells connected in series; A temperature collection unit is disposed in the battery box and is used to collect temperature information in the battery box; A main switch is arranged outside the battery box, and the heating circuit is connected in parallel with the plurality of single cells connected in series through the main switch; A main control module is connected to the switch in the box, the temperature acquisition unit, and the main switch. The main control module is used to control the heating speed of the heating circuit according to the temperature information in each battery box, adjust the single cells in different battery boxes to work within a preset working temperature range, and realize zoned thermal management; It also includes a first total voltage meter and a second total voltage meter, wherein the first total voltage meter is connected in parallel with both ends of the plurality of single cells connected in series, and the second total voltage meter is connected in parallel with the heating circuit and connected in parallel with both ends of the plurality of single cells connected in series through the main switch; The main control module is also used to diagnose whether the main switch is in a stuck state according to the control switch command and the voltage information collected by the first total voltmeter and the second total voltmeter.

2. The zoned thermal management battery system according to claim 1, characterized in that: The heating circuit also includes an ammeter and a voltmeter, the ammeter is connected in series with the heating plate and the switch in the box, and the voltmeter is connected in parallel with the heating plate; the ammeter and the voltmeter are respectively connected to the main control module; The ammeter is used to collect current information of the heating circuit, and the voltmeter is used to collect voltage information at both ends of the heating plate.

3. The zoned thermal management battery system according to claim 2, characterized in that: The main control module calculates the resistance information of the heating plate in each battery box according to the current information and the voltage information, and outputs differentiated PWM control switch instructions to the switches in different battery boxes according to the resistance information and the temperature information, thereby controlling the heating plates in different battery boxes to operate at different heating speeds, so that the single cells in different battery boxes all operate within a preset operating temperature range, thereby realizing zoned thermal management.

4. The zoned thermal management battery system according to claim 3, characterized in that: The main control module is also used to diagnose whether the resistance of the heating plate exceeds a preset resistance range or is broken according to the resistance information of the heating plate and the control switch command.

5. The zoned thermal management battery system according to claim 1, characterized in that: The main switch and the switch in the box are the same or different switch devices, and the switch devices include IGBT switches, MOSFET switches, SIC switches and relays.

6. The zoned thermal management battery system according to claim 1, characterized in that: The heating sheet is attached to the surface of the plurality of single cells connected in series, and the heating sheet is composed of one of a resistance wire, a PTC heating element, and a graphene heating film.

7. The zoned thermal management battery system according to claim 2, characterized in that: The ammeter is a Hall sensor or a shunt.

8. The zoned thermal management battery system according to claim 1, characterized in that: The voltmeter, the first total voltmeter and the second total voltmeter all include a series resistor voltage divider circuit and an A / D conversion module.

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