A low-voltage battery system for electric vehicles using sodium batteries

Abstract

This utility model discloses a low-voltage battery system for electric vehicles using sodium batteries, comprising a battery management module, several sodium-ion batteries connected in series to form a sodium-ion battery pack, several temperature sensors, a shunt, a discharge switch composed of several MOSFETs, a total positive output terminal, a total negative output terminal, and a one-button start switch. The system's output voltage matches the original vehicle's lead-acid battery, allowing for direct replacement without modifying the vehicle's electrical circuit, demonstrating strong adaptability. After undervoltage lockout, the system can be restarted by pressing and holding the one-button start switch, avoiding the cumbersome operation of external jump-starting and improving user experience. Temperature sensors monitor cell temperature in real time, preventing the impact of high / low temperatures on battery performance. The shunt, in conjunction with the total current detection unit, provides overcurrent protection, extending system lifespan. Sodium-ion batteries eliminate the need for complex protection for individual cells, reducing costs by more than 30% compared to lithium-ion battery systems, making them easier to scale up.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage batteries for electric vehicles, specifically a low-voltage battery system for electric vehicles using sodium batteries. Background Technology

[0002] The low-voltage battery in an electric vehicle stores electrical energy to power the vehicle's starting system and low-voltage electrical components (such as lights and the central control system). Currently, most low-voltage batteries in electric vehicles on the market are lead-acid batteries, but they have inherent drawbacks that are difficult to overcome: 1) Poor start-up convenience: When the vehicle is parked for a long time, the lead-acid battery will slowly lose power, causing the vehicle to fail to start due to low battery. It is necessary to find an external power source with a suitable voltage and jumper cables to perform a "jump-start" operation, which is cumbersome and has a poor user experience. 2) Lifespan is easily affected: Once a lead-acid battery is over-discharged (completely depleted), its internal electrode structure will be irreversibly damaged, resulting in a precipitous reduction in its lifespan. 3) Poor low-temperature performance: In low-temperature environments, the ion conduction efficiency of lead-acid batteries decreases, and the discharge capacity is significantly weakened, further increasing the difficulty of starting the vehicle.

[0003] To address these issues, the industry has attempted to replace lead-acid batteries with lithium-ion batteries. However, lithium-ion batteries require real-time data acquisition (such as voltage and temperature) and independent protection for individual cells, which increases the complexity of the battery management system and keeps the overall cost high, making it difficult to promote and apply them on a large scale.

[0004] Therefore, those skilled in the art have provided a low-voltage battery system for electric vehicles using sodium batteries to solve the problems mentioned in the background art. Utility Model Content

[0005] The purpose of this invention is to provide a low-voltage battery system for electric vehicles using sodium batteries, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A low-voltage battery system for electric vehicles using sodium batteries includes a battery management module, several sodium-ion batteries connected in series to form a sodium-ion battery pack, several temperature sensors, a shunt, a discharge switch composed of several MOSFETs, a total positive output terminal, a total negative output terminal, a one-button start switch, an indicator light, and a total voltage sampling harness for sampling the total voltage of the sodium-ion battery pack. The battery management module integrates a logic control unit, a switch output unit, a voltage signal analog-to-digital converter unit, a current signal analog-to-digital converter unit, a temperature signal analog-to-digital converter unit, a total voltage detection unit, a total current detection unit, a signal amplifier, a temperature detection unit, and a button status detection unit. The battery management module is electrically connected to the total positive and total negative terminals of the sodium-ion battery pack through the total voltage sampling harness, electrically connected to the cells of the sodium-ion battery pack through the temperature sensor, and connected in series with the main circuit through the shunt. The Dout interface of the battery management module is electrically connected to the gate of the MOS transistor in the discharge switch. The battery management module is electrically connected to the one-button start switch through the button status detection unit. The battery management module is also electrically connected to the indicator light.

[0007] As a further aspect of this invention: the total voltage signal of the sodium-ion battery pack collected by the total voltage detection unit is converted into a digital signal by the voltage signal analog-to-digital converter and then input to the logic control unit.

[0008] As a further improvement of this utility model: the total current detection unit collects the total current signal through the shunt, and after being conditioned by the signal amplifier, the current signal analog quantity to digital quantity unit converts it into a digital quantity input to the logic control unit.

[0009] As a further improvement of this utility model: the temperature detection unit collects the cell temperature signal through the temperature sensor, converts it into a digital signal through the temperature signal analog-to-digital converter, and inputs it to the logic control unit.

[0010] As a further improvement of this utility model, the switch output unit controls the conduction and cutoff of the discharge switch by outputting a high level or a low level.

[0011] As a further improvement of this utility model: the system is at least compatible with 12V and 24V voltage platforms; the undervoltage preset value 1 of the 12V voltage platform is 11.6V and the undervoltage preset value 2 is 9V, the undervoltage preset value 1 of the 24V voltage platform is 23.2V and the undervoltage preset value 2 is 18V; the current setting value 1 of both voltage platforms is 1A.

[0012] As a further improvement of this utility model: the activation trigger time of the one-button start switch is 2 seconds, and the illumination time of the indicator light is 5 minutes.

[0013] Compared with the prior art, the beneficial effects of this utility model are: 1. Seamless Replacement: The system output voltage matches the original vehicle lead-acid battery, allowing for direct replacement without modifying the vehicle's electrical circuit, making it highly adaptable; 2. No power jumper required: After a low voltage power failure, simply press and hold the one-button start switch to restart the system, avoiding the cumbersome operation of external power jumper and improving the user experience; 3. Stable and reliable performance: The temperature sensor monitors the cell temperature in real time to avoid the impact of high / low temperatures on battery performance; the shunt and total current detection unit work together to achieve overcurrent protection and extend system life; 4. Low cost: Sodium-ion batteries do not require complex protection for individual cells, reducing costs by more than 30% compared to lithium-ion battery systems, making them easier to promote on a large scale. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the internal structure of the battery management module in this utility model; Figure 3 This is a schematic diagram of the workflow of this utility model.

[0015] In the diagram: 1-Battery management module, 101-Logic control unit, 102-Switch output unit, 103-Analog to digital voltage signal unit, 104-Analog to digital current signal unit, 105-Analog to digital temperature signal unit, 106-Total voltage detection unit, 107-Total current detection unit, 108-Signal amplifier, 109-Temperature detection unit, 110-Button status detection unit; 2-Discharge switch, 3-Shunt, 4-Total positive output terminal, 5-Total negative output terminal, 6-Sodium-ion battery pack, 7-Temperature sensor, 8-One-button start switch, 9-Indicator light. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] Please see Figures 1-3 In this embodiment of the present invention, a low-voltage battery system for an electric vehicle using sodium batteries is provided. The system includes a battery management module 1, several sodium-ion batteries connected in series to form a sodium-ion battery pack 6, several temperature sensors 7, a shunt 3, a discharge switch 2 composed of several MOS transistors, a total positive output terminal 4, a total negative output terminal 5, a one-button start switch 8, an indicator light 9, and a total voltage sampling harness for sampling the total voltage of the sodium-ion battery pack 6.

[0018] Among them, the battery management module 1 is the core control unit of the system, which integrates: logic control unit 101: receiving and processing various detection signals and outputting control commands; The digital output unit 102 controls the opening and closing of the discharge switch 2 by outputting a high level / low level; The analog-to-digital voltage signal conversion unit 103 converts the analog signal acquired by the total voltage detection unit into a digital signal. The analog-to-digital converter 104 converts the analog signal acquired by the total current detection unit into a digital signal. The analog-to-digital unit 105 converts the analog signal acquired by the temperature detection unit into a digital signal. The total voltage detection unit 106 collects the total voltage of the sodium-ion battery pack 6 in real time through the total voltage sampling harness. The total current detection unit 107 collects the total current of the main circuit in real time through the shunt 3; The signal amplifier 108 conditions and amplifies the weak current signal collected by the total current detection unit 107; Temperature detection unit 109 collects the temperature of sodium-ion battery pack 6 cells in real time through temperature sensor 7; The button status detection unit 110 detects the pressed state of the one-button start switch 8 and transmits it to the logic control unit 101.

[0019] Connection relationships between components: Battery management module 1 and sodium-ion battery pack 6 are connected to the positive and negative terminals via a total voltage sampling harness to achieve total voltage sampling. Battery management module 1 is connected to temperature sensor 7 via a signal line to collect cell temperature; Battery management module 1 is connected in series with shunt 3 in the main circuit to collect the total current. Battery management module 1 and discharge switch 2 are connected to the gate of MOSFET via Dout interface to control the switch on and off; The battery management module 1 is connected to the one-button start switch 8 through the button status detection unit 110 to receive the start trigger signal; Battery management module 1 is connected to indicator light 9 via a signal line to control the indicator light to turn on / off.

[0020] This utility model will be described in detail with reference to specific parameters and workflow: 1. Core parameter presets This system is compatible with at least two mainstream low-voltage voltage platforms for electric vehicles: 12V and 24V. The preset parameters are as follows: 2. Workflow integration Figure 3 1) Normal working status judgment The total voltage detection unit 106 of the battery management module 1 collects the total voltage U of the sodium-ion battery pack 6 in real time, and the logic control unit 101 determines the system status based on the voltage and current signals. State 1: Normal power supply: If U > undervoltage preset value 1, the switch output unit 102 outputs a high level, the discharge switch 2 is turned on, and the system supplies power to the whole vehicle through the main positive / negative output terminal; State 2: Low power lockout: If the undervoltage preset value 2 < U ≥ undervoltage preset value 1, the total current detection unit 107 synchronously detects the total discharge current. If the current is greater than the current set value by 1, the system will maintain power supply when the vehicle's electrical equipment is working. If the current is less than or equal to the current setting value 1, such as when the vehicle is parked, the system will time for 5 minutes. If the "undervoltage + low current" condition is met continuously within 5 minutes, the switch output unit 102 will output a low level, the discharge switch 2 will be turned off, and the system will enter the power-off state. State 3: Deep undervoltage shutdown: If U≤ undervoltage preset value 2, the switch output unit 102 directly outputs a low level, the discharge switch 2 is turned off, and the system enters the shutdown state and requires external power to be turned on to wake it up.

[0021] 2) System Startup Control Start-up from power-off state: Press and hold the one-button start switch for 82 seconds to prevent accidental touch. The button status detection unit 110 transmits the signal to the logic control unit 101, the switch output unit 102 switches to high level, the discharge switch 2 is turned on, and the system starts up. At the same time, the indicator light 9 lights up for 5 minutes and then automatically turns off to remind the operator. Deep undervoltage shutdown start-up: After external power is applied to restore U to "undervoltage preset value 2 < U ≥ undervoltage preset value 1", repeat the above operation of pressing and holding the one-button start switch to start the system.

[0022] Analysis shows that: the output voltage of this system matches the original vehicle's lead-acid battery, allowing for direct replacement without modifying the vehicle's electrical circuit, demonstrating strong adaptability; after undervoltage lockout, the system can be restarted by pressing and holding the one-button start switch, avoiding the cumbersome operation of external jump-start and improving user experience; the temperature sensor monitors the cell temperature in real time, preventing the impact of high / low temperatures on battery performance; the shunt and total current detection unit work together to achieve overcurrent protection, extending system life; sodium-ion batteries do not require complex protection for individual cells, reducing costs by more than 30% compared to lithium-ion battery systems, making them easier to promote on a large scale.

[0023] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An electric vehicle low voltage battery system employing a sodium battery, characterized by: Includes a battery management module (1), several sodium-ion batteries connected in series to form a sodium-ion battery pack (6), several temperature sensors (7), a shunt (3), a discharge switch (2) composed of several MOS transistors, a total positive output terminal (4), a total negative output terminal (5), a one-button start switch (8), an indicator light (9), and a total voltage sampling harness for sampling the total voltage of the sodium-ion battery pack (6); The battery management module (1) integrates a logic control unit (101), a switch output unit (102), a voltage signal analog to digital conversion unit (103), a current signal analog to digital conversion unit (104), a temperature signal analog to digital conversion unit (105), a total voltage detection unit (106), a total current detection unit (107), a signal amplifier (108), a temperature detection unit (109), and a key status detection unit (110). The battery management module (1) is electrically connected to the total positive and total negative terminals of the sodium-ion battery pack (6) through the total voltage sampling harness, electrically connected to the cells of the sodium-ion battery pack (6) through the temperature sensor (7), and connected in series with the main circuit through the shunt (3). The Dout interface of the battery management module (1) is electrically connected to the gate of the MOS transistor in the discharge switch (2). The battery management module (1) is electrically connected to the one-button start switch (8) through the button status detection unit (110). The battery management module (1) is electrically connected to the indicator light (9).

2. The electric vehicle low-voltage battery system employing sodium batteries of claim 1, wherein: The total voltage signal of the sodium-ion battery pack (6) collected by the total voltage detection unit (106) is converted into a digital signal by the voltage signal analog-to-digital converter (103) and then input to the logic control unit (101).

3. The electric vehicle low voltage battery system employing sodium batteries of claim 1, wherein: The total current detection unit (107) collects the total current signal through the shunt (3), which is then conditioned by the signal amplifier (108) and converted into a digital signal by the analog-to-digital current conversion unit (104) and input to the logic control unit (101).

4. The electric vehicle low voltage battery system employing sodium batteries of claim 1, wherein: The temperature detection unit (109) collects the cell temperature signal through the temperature sensor (7), converts it into a digital signal through the temperature signal analog-to-digital converter (105), and inputs it to the logic control unit (101).

5. The electric vehicle low voltage battery system employing sodium batteries of claim 1, wherein: The switching output unit (102) controls the conduction and cutoff of the discharge switch (2) by outputting a high level or a low level.

6. The electric vehicle low voltage battery system employing sodium batteries of claim 1, wherein: The system is compatible with at least 12V and 24V voltage platforms; the undervoltage preset value 1 for the 12V voltage platform is 11.6V and the undervoltage preset value 2 is 9V, and the undervoltage preset value 1 for the 24V voltage platform is 23.2V and the undervoltage preset value 2 is 18V; the current setting value 1 for both voltage platforms is 1A.

7. The electric vehicle low voltage battery system employing sodium batteries of claim 1, wherein: The start-up trigger time of the one-button start switch (8) is 2 seconds, and the illumination time of the indicator light (9) is 5 minutes.

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