An on-board battery charging control system

Abstract

This invention discloses an on-board battery charging control system, including a battery pack, a controller, and an on-board charger. The positive terminal of the controller's power unit is connected to the positive discharge terminal of the battery pack. The on-board charger has a built-in first relay, and the positive discharge terminal of the battery pack is connected to the control circuit power supply of the controller through the first relay. A second power-off switch is provided between the battery pack and the controller, and the first power-off switch is connected to the battery pack. The battery pack includes a cell module and a power management module connected to the cell module. This application sets an emergency power-off switch to control the vehicle's prohibition of driving while charging, thus doubly ensuring vehicle safety. By collecting the battery charging current, voltage, and temperature through the power management module, the battery is charged on demand, effectively avoiding various situations that easily occur in the blind charging state of lithium batteries, such as incomplete charging, overcharging, overheating during charging, and low-temperature charging.

Description

Technical Field

[0001] This invention relates to the field of vehicle charging technology, specifically a vehicle battery charging control system. Background Technology

[0002] Lightweight lithium battery pallet trucks are widely used due to their compact size and ease of operation. The industry commonly employs a low-cost design scheme involving blind charging of lithium batteries and chargers. However, because the charger's charging curve in this scheme is fixed and cannot be customized for the specific lithium battery, the lithium battery frequently experiences issues such as incomplete charging, overcharging, overheating during charging, and low-temperature charging, significantly reducing battery lifespan. Furthermore, the system requires an external relay to cut off the power to the controller's dedicated restricted access port via an external circuit to prevent the vehicle from moving during charging. However, if the relay contacts are stuck together, this port becomes ineffective, posing a risk that the vehicle can move while charging. Summary of the Invention

[0003] The purpose of this invention is to provide an on-board battery charging control system to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: An on-board battery charging control system includes a battery pack, a controller, and an on-board charger, wherein the battery pack, controller, and on-board charger are connected via a bus signal. The positive terminal of the power unit of the controller is connected to the positive terminal of the discharge of the battery pack. The on-board charger has a built-in first relay. The positive terminal of the discharge of the battery pack is connected to the power supply of the control circuit of the controller through the first relay. A second power-off switch is provided between the battery pack and the controller. The first power-off switch is connected to the battery pack. The battery pack includes a cell module and a power management module connected to the cell module.

[0005] As a further aspect of the present invention, the vehicle charger is connected in parallel across both ends of the battery pack.

[0006] As a further aspect of the present invention: a fuse is provided between the positive terminal of the power unit of the controller and the positive terminal of the discharge of the battery pack, and a fuse is provided between the second power-off switch and the battery pack.

[0007] As a further aspect of the present invention: the bus is a CAN bus, and an instrument and a handle are also connected to the bus.

[0008] As a further aspect of the present invention: the second power-off switch is connected to the power supply of the control circuit of the handle, and the second power-off switch is connected to the power supply of the control circuit of the handle through a diode.

[0009] As a further aspect of the present invention: the positive discharge terminal of the battery pack is connected to the power supply of the control circuit of the instrument through a first relay, and a fuse is provided between the battery pack and the instrument.

[0010] As a further aspect of the present invention: the battery cell module is provided with a first temperature sensor and a second temperature sensor, and the first temperature sensor and the second temperature sensor are connected to the temperature control port on the power management module.

[0011] As a further aspect of the present invention: the battery cell module is equipped with a current sensor, and the current sensor is connected to the power control port of the power management module.

[0012] As a further aspect of the present invention: the power management module is connected to a power plug-in via a second relay, the power plug-in is connected to the power management module via a bus, and the power supply of the control circuit of the power plug-in is connected to the control power supply of the power management module.

[0013] As a further aspect of the present invention: the power supply of the control circuit of the power management module is connected to the first power-off switch.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This application provides a double guarantee for vehicle safety by setting an emergency power-off switch to control the vehicle's prohibition of driving while charging. In addition, this application adds a power management module to the currently commonly used protection board based on the lithium battery pack solution with CAN communication charging and discharging port. 2. This application collects battery charging current, voltage, and temperature through a power management module, and outputs charging voltage and current through a charging strategy via a charger, enabling the battery to be charged on demand. This effectively avoids various situations that are prone to occur in the blind charging state of lithium batteries, such as incomplete charging, overcharging, overheating of the battery during charging, and low-temperature charging. 3. This application monitors the discharge current through the power management module and implements a sleep function for the battery to prevent damage to the battery caused by long-term low-current discharge of the lithium battery pack, thus effectively extending the battery's service life. 4. At the end of the charging process, this application uses a power management system to evaluate the performance parameters of the battery cell modules and then performs trickle equalization charging on each cell module. The application of the power management module effectively avoids the phenomenon of unbalanced battery terminal voltage caused by individual differences and temperature differences among battery cells, thereby achieving the effect of balancing the characteristics of each battery in the battery pack and effectively extending battery life. Attached Figure Description

[0015] Figure 1 This is the circuit diagram for this embodiment; Figure 2 This is a schematic diagram of the lithium battery structure in this embodiment; Figure 3 This is a schematic diagram of the lithium battery capacity in this embodiment.

[0016] In the diagram: 1-Battery pack, 11-Cell module, 12-Power management module, 13-Second relay, 14-Power connector, 15-First temperature sensor, 16-Second temperature sensor, 17-Current sensor, 2-Controller, 3-Instrument, 4-On-board charger, 41-First relay, 5-Handle, 61-First power-off switch, 62-Second power-off switch, 7-Diode. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In this embodiment of the invention, an on-board battery charging control system includes a battery pack 1, a controller 2, an instrument panel 3, an on-board charger 4, and a handle 5. The battery pack 1, controller 2, instrument panel 3, on-board charger 4, and handle 5 are connected via a CAN bus signal. The on-board charger 4 is connected in parallel to both ends of the battery pack 1. A fuse is provided between the positive terminal of the power unit of controller 2 and the positive terminal of the discharge of battery pack 1. A fuse is provided between the second power-off switch 62 and battery pack 1. The second power-off switch 62 is connected to the power supply of the control circuit of handle 5. The second power-off switch 62 is connected to the power supply of the control circuit of handle 5 through diode 7. The on-board charger 4 has a built-in first relay 41. The positive terminal of the discharge of battery pack 1 is connected to the power supply of the control circuit of controller 2 through the first relay 41. A second power-off switch 62 is provided between battery pack 1 and controller 2. The first power-off switch 61 is connected to battery pack 1. The positive terminal of the discharge of battery pack 1 is connected to the power supply of the control circuit of instrument 3 through the first relay 41. A fuse is provided between battery pack 1 and instrument 3.

[0019] The battery pack 1 includes a cell module 11 and a power management module 12 connected to the cell module 11. The cell module 11 is equipped with a first temperature sensor 15 and a second temperature sensor 16, which are connected to the temperature control port on the power management module 12. The cell module 11 is also equipped with a current sensor 17, which is connected to the power control port of the power management module 12. The power management module 12 is connected to a power plug 14 via a second relay 13. The power plug 14 is connected to the power management module 12 via a bus. The control circuit power supply of the power plug 14 is connected to the control power supply of the power management module 12. The control circuit power supply of the power management module 12 is connected to the first power-off switch 61.

[0020] Example 1 Please see Figure 1-3 In this embodiment of the invention, a vehicle battery charging control system includes a battery pack 1, a controller 2, an instrument 3, a vehicle charger 4, and a handle 5, wherein the vehicle charger 4 is connected in parallel to both ends of the battery pack 1.

[0021] The positive terminal 2B+ of the power unit of controller 2 is connected to the positive terminal 1B+ of the discharge terminal of battery pack 1 through fuse F3. The positive terminal 1B+ of the discharge terminal of battery pack 1 is input to the control circuit power supply KS1 of controller 2 through the normally closed contact of the first relay 41 of vehicle charger 4, fuse F1 and second power-off switch 62. The second power-off switch 62 is input to the power supply KS2 of instrument 3 through diode 7. The power supply KS2 of instrument 3 is connected to battery pack 1 through fuse F2 and the normally open contact of the first relay 41 built into vehicle charger 4.

[0022] The CAN communication ports (CANH1, CANL1) of battery pack 1 are electrically connected to the CAN communication ports (CANH2, CANL2) of controller 2, the CAN communication ports (CANH3, CANL3) of instrument 3, the CAN communication ports (CANH4, CANL4) of on-board charger 4, and the CAN communication ports (CANH5, CANL5) of handle 5. The emergency power-off switch includes a first power-off switch 61 and a second power-off switch 62. When the emergency power-off switch is activated, the first power-off switch 61 and the second power-off switch 62 will have relatively independent voltage signals, and the two power-off switches work independently.

[0023] Battery pack 1 adopts a charging and discharging port scheme, including cell module 11, power management module 12, second relay 13 and power plug 14. The voltage sensor of cell module 11 is electrically connected to ports B1-B8 in power management module 12. The first temperature sensor 15 and the second temperature sensor 16 of cell module 11 are electrically connected to ports T1+, T1, T2+ and T2 in power management module 12. Battery pack 1 is equipped with current sensor 17 for detecting charging and discharging current.

[0024] In the power management module 12, the KS+ and KS ports are connected to the first power-off switch 61 of the emergency power-off switch. When the first power-off switch 61 is closed, KS+ connects to KS, the contacts of the second relay 13 close, and the power management module 12 in the battery pack 1 is powered on.

[0025] When the vehicle charger 4 is not connected to the mains power, the emergency power-off switch is pulled up. The first power-off switch 61 and the second power-off switch 62 of the emergency power-off switch are turned on at the same time. KS+ of the power management module 12 in the battery pack 1 is turned on by KS. The power management module 12 in the battery pack 1 is powered on. The battery pack 1 performs a self-test. The normally closed contact of the first relay 41 of the vehicle charger 4 remains closed.

[0026] After the power management module 12 completes its self-test, the battery pack 1 outputs power supply 1B+. At the same time, the power supply 1B+ output by the battery pack 1 is input to the control power supply KS1 terminal of the controller 2 and the control power supply KS3 terminal of the handle 5 via the normally closed contact of the first relay 41 of the on-board charger 4, the safety wire F1, and the second power-off switch 62 of the emergency power-off switch. Another path is input to the control power supply KS2 terminal of the instrument 3 via the second power-off switch 62 of the emergency power-off switch and the diode 7. At this time, the battery pack 1, controller 2, instrument 3, and handle 5 complete their self-tests and establish CAN communication.

[0027] The power management module 12 of battery pack 1 collects the voltage, temperature and output current of the cell module 11 of battery pack 1, and transmits various status information of battery pack 1 in the CAN network through CAN communication. The power management module 12 of controller 2 reads the corresponding messages.

[0028] When the driver is in operation mode, i.e., when the intelligent handle 5 is pulled to bring the vehicle to the working position, handle 5 outputs various command signals such as vehicle lifting, lowering, forward, reverse, and emergency reversing, which are transmitted to controller 2 via CAN communication to control vehicle operation. During vehicle operation, controller 2 implements protection measures for battery pack 1 against low voltage, overvoltage, low temperature, high temperature, and overcurrent. Instrument 3 displays the vehicle's braking or running status on the screen via CAN communication. The vehicle's operating time is transmitted from controller 2 to instrument 3 via CAN communication and displayed by instrument 3. When a fault occurs in battery pack 1, controller 2, instrument 3, or handle 5 in the CAN communication network, the relevant fault code is displayed on instrument 3 via CAN message. When the vehicle is in a long-term standby state, battery pack 1, upon detecting continuous low-current discharge, shuts off its output voltage and enters a dormant state.

[0029] When the vehicle is charging, a voltage difference is generated in the coil of the built-in first relay 41 of the on-board charger 4, causing its normally open contact to close. The power output B+ of the battery pack 1 is supplied to the control power supply KS2 of the handle 5 through the normally open contact (closed at this time) of the built-in first relay 41 of the on-board charger 4 and the second fuse F2. The instrument panel 3 is powered on, and the real-time charging level of the battery pack 1 and the fault codes of the battery pack 1 and the on-board charger 4 are displayed on the instrument panel 3. The normally closed contact of the first relay 41 is open. The control power supply KS1 of the controller 2 is de-energized, and the vehicle cannot run. To prevent the normally closed contact of the first relay 41 from sticking and failing to disconnect the control power supply KS2 of the controller 2, after the vehicle on-board charger 4 is powered on and establishes CAN communication with the battery pack 1, the battery pack 1 sends a CAN message to the controller 2 and the handle 5. After receiving the charging message, the controller 2 disconnects the power output to the motor; after receiving the charging message, the handle 5 locks all action signals, and the vehicle cannot run.

[0030] The charging current and voltage of the vehicle on-board charger 4 are adjusted in real time by the power management module 12 in the battery pack 1 and the first temperature sensor 15, the second temperature sensor 16, the current sensor 17, and the voltage sensor of the lithium battery pack.

[0031] At the end of the charging process, the power management module 12 evaluates the performance parameters of the battery cell module 11 and transmits the relevant information to the vehicle charger 4 via CAN communication. The vehicle charger 4 then performs trickle equalization charging on the battery cell module 11, effectively avoiding the phenomenon of unbalanced battery terminal voltage caused by individual differences and temperature differences among battery cells. This achieves the effect of balancing the characteristics of each battery in the battery pack and effectively extends battery life.

[0032] When the CAN communication feedback of controller 2 is interrupted, handle 5 reports a communication fault and simultaneously locks all action signals to ensure that the vehicle cannot operate. When the battery pack 1, controller 2, instrument panel 3, vehicle on-board charger 4, or handle 5 in the CAN communication network malfunction, the relevant fault codes are displayed on instrument panel 3 via CAN messages.

[0033] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A vehicle-mounted battery charging control system, characterized in that, It includes a battery pack (1), a controller (2), and an on-board charger (4), which are connected by a bus signal. The positive terminal of the power unit of the controller (2) is connected to the positive terminal of the discharge of the battery pack (1). The on-board charger (4) has a built-in first relay (41). The first relay (41) has a normally open contact and a normally closed contact. The positive terminal of the discharge of the battery pack (1) is connected to the power supply of the control circuit of the controller (2) through the normally closed contact of the first relay (41). The positive terminal of the discharge of the battery pack (1) is connected to the power supply of the control circuit of the instrument (3) through the normally open contact of the first relay (41). When the on-board charger (4) is powered on, the coil of the first relay (41) generates a voltage difference, and its normally open contact closes and its normally closed contact opens. The positive terminal of the discharge of the battery pack (1) is connected to the power supply of the control circuit of the controller (2) through the first relay (41). A second power-off switch (62) is provided between the battery pack (1) and the controller (2). The first power-off switch (61) is connected to the battery pack (1). The battery pack (1) includes a cell module (11) and a power management module (12) connected to the cell module (11); The vehicle charger (4) is connected in parallel across the two ends of the battery pack (1); The power management module (12) collects the voltage, temperature and charging / discharging current of the battery cell module (11), and transmits the battery pack status information to the bus network through bus communication. The charging current and voltage of the vehicle charger (4) are adjusted in real time by the power management module (12) according to the collected voltage, current and temperature. At the end of the charging period, the power management module (12) evaluates the performance parameters of each cell module (11) and controls the on-board charger (4) to perform trickle equalization charging on each cell module (11); when the vehicle is in standby mode, the power management module (12) shuts off the output voltage when it detects that the battery is continuously discharging at a small current, and the battery pack (1) enters a dormant state.

2. The on-board battery charging control system according to claim 1, characterized in that, A fuse is provided between the positive terminal of the power unit of the controller (2) and the positive terminal of the discharge of the battery pack (1), and a fuse is provided between the second power-off switch (62) and the battery pack (1).

3. The on-board battery charging control system according to claim 1, characterized in that, The bus is a CAN bus, and an instrument (3) and a handle (5) are also connected to the bus.

4. The on-board battery charging control system according to claim 3, characterized in that, The second power-off switch (62) is connected to the power supply of the control circuit of the handle (5), and the second power-off switch (62) is connected to the power supply of the control circuit of the handle (5) through the diode (7).

5. The on-board battery charging control system according to claim 3, characterized in that, The positive discharge terminal of the battery pack (1) is connected to the control circuit power supply of the instrument (3) through the first relay (41), and a fuse is provided between the battery pack (1) and the instrument (3).

6. The on-board battery charging control system according to claim 1, characterized in that, The battery cell module (11) is equipped with a first temperature sensor (15) and a second temperature sensor (16), which are connected to the temperature control port on the power management module (12).

7. The on-board battery charging control system according to claim 1, characterized in that, The battery cell module (11) is equipped with a current sensor (17), which is connected to the power control port of the power management module (12).

8. The on-board battery charging control system according to claim 1, characterized in that, The power management module (12) is connected to a power plug (14) via a second relay (13). The power plug (14) is connected to the power management module (12) via a bus. The power supply of the control circuit of the power plug (14) is connected to the control power supply of the power management module (12).

9. A vehicle-mounted battery charging control system according to claim 1, characterized in that, The power supply of the control circuit of the power management module (12) is connected to the first power-off switch (61).

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