Energy storage control circuit and device

Abstract

The invention discloses an energy storage control circuit and device, and belongs to the technical field of battery management. The control panel is connected with the battery pack; two ends of the battery pack are connected in parallel with a charging loop, a discharging loop, a temperature control loop and a warning loop; adjusting the on-off of the charging loop and the discharging loop according to the temperature information of the temperature control loop, so that the temperature of the battery pack is increased to a temperature threshold value through the temperature control loop in a low-temperature environment; the temperature control loop is connected in parallel to the charging loop and the discharging loop of the battery pack, temperature rise control is carried out when the battery pack is charged and discharged, the operation condition of the battery is improved, the fuse is arranged to protect the charging loop, the discharging loop and the temperature control loop, and the safety of the battery is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management, and in particular to an energy storage control circuit and device. Background Art

[0002] In a low-temperature environment, the electrolyte and other substances inside a conventional battery will crystallize due to the low temperature. This is because the low temperature reduces the solubility of these substances, and some of the components originally dissolved in them begin to precipitate to form crystals. For example, lithium salts in lithium-ion batteries may crystallize at low temperatures. These crystals gradually accumulate inside the battery, which will have many adverse effects on the normal operation of the battery. When crystals appear inside the battery, these crystals will hinder the movement of ions between the positive and negative electrodes of the battery. As the crystals continue to increase inside the battery, they may puncture the diaphragm inside the battery. The diaphragm plays an important role in separating the positive and negative electrodes and preventing short circuits in the battery. Once the diaphragm is punctured, the positive and negative electrodes may come into direct contact, causing a battery short circuit.

[0003] Compared with conventional batteries, low-temperature batteries have been specially designed and improved in materials to provide relatively stable performance in low-temperature environments. However, even for low-temperature batteries, if they are not charged or are fast-charged and discharged for a long time at low temperatures, and the chemical changes inside the battery are continuing, new problems will arise. When not charged, the chemical reaction inside the battery may be relatively slow, but it is still ongoing, which will continuously consume some components inside the battery and produce some new substances and gases. The fast charging and discharging process will sharply accelerate the rate of chemical reactions inside the battery, and will also produce more gases and other substances. These gases accumulate inside the battery, and because the diffusion rate of gases in low-temperature environments is relatively slow, the internal pressure of the battery will increase, which will put the battery at risk of safety accidents, such as battery bulging, explosion and fire, etc. In some extreme low-temperature environments (-41°C), such as the polar night in the polar regions, long-term low-temperature weather in high-altitude cold areas, etc., once a safety accident occurs, it will not only cause equipment damage, but also endanger the lives of people. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an energy storage control circuit and device.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: an energy storage control circuit, comprising: Control panel; The control board is connected to the battery pack; The two ends of the battery pack are connected in parallel with a charging circuit, a discharging circuit, a temperature control circuit and a warning circuit; The on / off of the charging circuit and the discharging circuit are adjusted according to the temperature information of the temperature control circuit, so that the battery pack is heated to a temperature threshold through the temperature control circuit in a low temperature environment.

[0006] As a further description of the above technical solution: the positive electrode of the battery pack is connected to the first fuse, the negative electrode of the battery pack is connected to the shunt, and the control board is also connected to a display screen and a host computer.

[0007] As a further description of the above technical solution: the charging circuit includes a charging relay, the charging relay is connected to the first fuse, the other end of the charging relay is connected to the cathode of the first diode, the anode of the first diode is connected to the anode of the charger, and the cathode of the charger is connected to the shunt.

[0008] As a further description of the above technical solution: the discharge circuit includes a discharge relay, the discharge relay is connected to the first fuse, and the other end of the discharge relay is connected to the shunt.

[0009] As a further description of the above technical solution: one end of the discharge relay connected to the shunt is connected to a normally open synchronous switch, and the normally open synchronous switch is connected to the positive and negative electrodes of the discharge end.

[0010] As a further description of the above technical solution: the temperature control circuit includes a second fuse, one side of the second fuse is connected to the positive electrode of the first diode, the other side of the second fuse is connected to the heating relay, the other end of the heating relay is connected to the heating port, and the temperature is controlled to rise to the temperature threshold through the heating relay.

[0011] As a further description of the above technical solution: the warning circuit includes a buzzer relay, one end of the buzzer relay is connected to the first fuse, and the other end of the buzzer relay is connected to the buzzer port.

[0012] As a further description of the above technical solution: one side of the first fuse connected to the charging relay is also connected to the anode of the second diode, the cathode of the second diode is connected to the control switch, the other end of the control switch is connected to the cathode of the third diode, and the anode of the third diode is connected to the anode of the charger; An anode of the second diode is connected to the buzzer relay.

[0013] As a further description of the above technical solution: the cathode of the shunt and the third diode is connected to a DCDC converter, and the anode and the ground terminal of the DCDC converter are connected to the control board; Both ends of the coils of the charging relay, the discharging relay, the heating relay and the buzzer relay are connected to the control board.

[0014] Also included is an energy storage device, which is applicable to any control circuit in the above technical solutions, including: Circuit boards; A battery pack is arranged below the circuit board; The circuit board is provided with a control board, a shunt, a first fuse, a charging relay, a discharging relay, a heating relay, a buzzer relay, a second fuse, a DCDC converter, a first diode, a second diode or a third diode.

[0015] The above technical solution has the following advantages or beneficial effects: By connecting a temperature control circuit in parallel to the charging circuit and discharging circuit of the battery pack, the temperature rise is controlled when the battery pack is charging and discharging, thereby improving the battery operating conditions. By setting a fuse to protect the charging circuit, discharging circuit and temperature control circuit, the battery safety is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the control circuit proposed by the present invention; Figure 2 The structure of the energy storage device proposed by the present invention is shown in FIG. Figure 1 ; Figure 3 The structure of the energy storage device proposed by the present invention is shown in FIG. Figure 2 .

[0017] Legend: 1. Control board; 2. Battery pack; 3. First fuse; 4. Shunt; 5. Display screen; 6. Host computer; 7. Charging relay; 8. First diode; 9. Discharging relay; 10. Normally open synchronous switch; 11. Second fuse; 12. Heating relay; 13. Buzzer relay; 14. Second diode; 15. Control switch; 16. Third diode; 17. DCDC converter; 18. Circuit board. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Reference Figure 1An embodiment of the present invention provides: an energy storage control circuit, comprising: a control board 1; the control board 1 is connected to a battery pack 2; a charging circuit, a discharging circuit, a temperature control circuit and a warning circuit are connected in parallel at both ends of the battery pack 2; the on-off of the charging circuit and the discharging circuit is adjusted according to the temperature information of the temperature control circuit, so that the battery pack 2 is heated to a temperature threshold through the temperature control circuit in a low temperature environment.

[0020] In this embodiment, the control board 1 plays a core control and coordination role. It is connected to the battery pack 2 to obtain relevant status information of the battery pack 2 and control operations thereof. The main function of the charging circuit is to provide charging current for the battery pack 2 and transmit the electric energy of the external power supply to the battery pack 2 so that the power of the battery pack 2 can be replenished. During the charging process, it is necessary to reasonably control the size of the charging current and the charging time and other parameters according to the current state of the battery pack 2 (such as power, temperature, etc.) to ensure the safety and efficiency of the charging process. The discharge circuit is used to release the electric energy stored in the battery pack 2 to provide power support for the external load. The temperature control circuit is responsible for monitoring the temperature information of the battery pack 2. It senses the temperature status of the battery pack 2 in real time through devices such as temperature sensors, and feeds back the temperature information to the control board 1. Its purpose is to take corresponding measures to increase the temperature of the battery pack 2 when the battery pack 2 is in a low temperature environment, so that it reaches a suitable temperature threshold, thereby ensuring that the battery pack 2 can still perform normal charging and discharging operations in a low temperature environment. The function of the warning circuit is to send a warning signal when an abnormal situation occurs in the battery pack 2, so as to promptly notify the user or relevant operator to take corresponding measures. These abnormal conditions may include the battery pack 2 being too high or too low in temperature, overcharged, over-discharged, short-circuited, etc. By connecting a temperature control circuit in parallel to the charging circuit and the discharging circuit of the battery pack 2, the temperature rise control is performed when the battery pack 2 is charged and discharged, the battery operating conditions are improved, and the charging circuit, the discharging circuit and the temperature control circuit are protected by setting a fuse to improve the battery safety.

[0021] The positive electrode of the battery pack 2 is connected to the first fuse 3 , the negative electrode of the battery pack 2 is connected to the shunt 4 , and the control board 1 is also connected to a display screen 5 and a host computer 6 .

[0022] In this embodiment, the battery pack 2 is of model JN2467ZK01, and the rated breaking current of the first fuse 3 is 200A, which plays the role of overcurrent protection. When a short circuit occurs in the battery pack 2 (which may be caused by internal short circuit of the battery, improper connection of the external line, etc.), the current will increase sharply instantly. At this time, the first fuse 3 will be blown because the current passing through it exceeds its rated breaking current, thereby cutting off the connection between the positive electrode of the battery pack 2 and the subsequent circuit. The rated current of the shunt 4 is 200A, which measures the current of the battery pack 2 and feeds back the current information to the control board 1. The control board 1 is connected to the display screen 5 and the host computer 6. The display screen 5 can intuitively display the relevant information of the battery pack 2. The host computer 6 can receive various detailed data of the battery pack 2 uploaded by the control board 1, including real-time current, voltage, temperature, power and other information, and then further analyze and process these data. The host computer 6 can also remotely control the battery pack 2 through the control board 1.

[0023] The charging circuit includes a charging relay 7, which is connected to the first fuse 3, the other end of the charging relay 7 is connected to the cathode of the first diode 8, the anode of the first diode 8 is connected to the anode (C+) of the charger, and the cathode (C-) of the charger is connected to the shunt 4.

[0024] In this embodiment, the first diode 8 plays a role in preventing the current from flowing in the reverse direction. When the charger charges the battery pack 2, the current can only flow in from the positive electrode of the first diode 8, pass through the inside of the diode, and then flow out from the negative electrode into the charging relay 7, and then flow to the battery pack 2. This ensures that during the charging process, the current flows in the correct direction. The shunt 4 is connected to the negative electrode of the battery pack 2. By measuring the current passing through the shunt 4, the current situation during the charging process can be accurately known, and the charging process can be controlled and monitored. The first diode 8 is a 50A power diode, and the charging relay 7 is 50A, which is energized during charging.

[0025] The discharge circuit includes a discharge relay 9, which is connected to the first fuse 3, and the other end of the discharge relay 9 is connected to the shunt 4. One end of the discharge relay 9 connected to the shunt 4 is connected to a normally open synchronous switch 10, and the normally open synchronous switch 10 is connected to the positive electrode (P+) and the negative electrode (P-) of the discharge end.

[0026] In this embodiment, the discharge relay is 200A. When discharge is required, the normally open synchronous switch 10 is pressed, the discharge relay 9 is closed, and the current can be transmitted from the positive pole of the battery pack 2, through the first fuse 3, and then enter the discharge relay 9, and then enter the external load for power supply. The first fuse 3 performs overcurrent protection on the circuit during the discharge process.

[0027] The temperature control circuit includes a second fuse 11, one side of the second fuse 11 is connected to the positive electrode of the first diode 8, the other side of the second fuse 11 is connected to a heating relay 12, and the other end of the heating relay 12 is connected to a heating port, and the temperature is controlled to rise to a temperature threshold through the heating relay 12.

[0028] In this embodiment, the second fuse 11 is 15A, which serves as an overcurrent protection for the heating relay 12. The heating relay 12 is 20A. When the temperature of the battery pack 2 is lower than the set temperature threshold, or the control board 1 determines that heating needs to be started based on the temperature information fed back by the temperature control loop, the heating relay 12 will be closed, so that the current flows through the heating relay 12 to the subsequent heating port. The heating port is connected to an external heating device (which is the prior art, not shown in the figure), such as a heating wire or a heating sheet, to heat the circuit system, generate heat and transfer it to the battery pack 2, thereby achieving the effect of heating the battery pack 2.

[0029] The warning circuit includes a buzzer relay 13 , one end of the buzzer relay 13 is connected to the first fuse 3 , and the other end of the buzzer relay 13 is connected to the buzzer port.

[0030] In this embodiment, the buzzer relay 13 is connected to the first fuse 3. When the first fuse 3 blows, or when the control board 1 receives abnormal information from the battery pack 2 and determines that a warning signal needs to be issued, a signal will be issued to close the buzzer relay 13 to alert the staff.

[0031] One side of the first fuse 3 connected to the charging relay 7 is also connected to the positive electrode of the second diode 14, the negative electrode of the second diode 14 is connected to the control switch 15, the other end of the control switch 15 is connected to the negative electrode of the third diode 16, and the positive electrode of the third diode 16 is connected to the positive electrode of the charger; the positive electrode of the second diode 14 is connected to the buzzer relay 13.

[0032] In this embodiment, the anode of the second diode 14 is connected to one side of the first fuse 3 connected to the charging relay 7. The second diode 14 plays a role of isolation and protection in the circuit. The anode of the second diode 14 is also connected to the buzzer relay 13. When the first fuse 3 is disconnected, the battery pack 2 transmits current to the buzzer relay 13 through the DCDC converter 17 for warning. By setting the control switch 15, the current on and off of the circuit is controlled.

[0033] The cathode of the shunt 4 and the third diode 16 is connected to a DCDC converter 17, and the anode and ground of the DCDC converter 17 are connected to the control board 1; both ends of the coils of the charging relay 7, the discharging relay 9, the heating relay 12 and the buzzer relay 13 are connected to the control board 1.

[0034] Working principle: When the battery energy storage system is turned on, the positive circuit of the battery pack 2 is turned on, and the DCDC converter 17 is a DC to DC converter. After the input terminal DC / DC IN is powered, it outputs a 12V voltage to supply the control board 1. At this time, the control board 1 works normally, and detects the voltage, current, temperature and other data of the battery pack 2 to further control the circuit. For example, according to the voltage detection, the charging relay 7, the discharge relay 9, and the buzzer relay 13 are controlled to be attracted and released; according to the current detection, the charging relay 7 and the discharge relay 9 are controlled to perform protection actions; according to the temperature detection, the charging relay 7 and the discharge relay 9 are controlled to protect, and the heating relay 12 is controlled to be attracted and released to perform heating actions. The first fuse 3 protects against the discharge current, and the second fuse 11 protects against the heating current. The first diode 8 protects against the charging current and prevents reverse current from being generated during the discharge process. When the current passes through the shunt 4, the current value information and the current direction are provided to the control board 1 by measuring the current signal. The control board 1 supplies the display screen 5 with voltage and power information through the 485 communication interface and 5V output voltage; it is connected to the host computer 6 through the 485 communication interface, and the host computer 6 software can be used to view the battery system information and update the program of the control board 1.

[0035] This embodiment also provides an embodiment of a circuit control method, including: After the battery pack switch is turned on, the battery energy storage system performs a self-check, and after the self-check, the discharge relay 9 and the charge relay 7 are turned on in sequence.

[0036] After the control switch 15 is turned off, the battery energy storage system is turned off, and the whole system has the functions of automatic shutdown at low voltage and automatic start-up during charging. The battery energy storage system can collect single cell voltage, temperature, and current, and can perform SOC calculations and control charging relay 7, discharge relay 9, and heating relay 12 based on the collected information. Avoid overcharging, over-discharging, overcurrent, overtemperature and other situations to protect the energy storage system. If an abnormality is detected, the program will continue to read data. During the data reading period, the charging relay 7 and the discharge relay 9 will be controlled to be turned on and off. Only the charging relay 7 is turned on between 8.5V (minimum start voltage) and 20.3V (undervoltage protection voltage). To realize the feeding charging function, the control switch 15 can be bypassed for charging.

[0037] When the total voltage of the battery system is lower than the undervoltage protection voltage of 20.3V, the control switch 15 cannot turn on the battery. At this time, charging can be forced to open the charging relay 7 to realize the charging function. If it is a sub-zero low temperature environment, charging and heating are performed first, and charging begins after the battery energy storage system temperature rises above zero. After turning on the control switch 15 for a delay of 5 seconds, if no data is still read, it is determined to be in a fault state, and the charging relay 7, the discharge relay 9 and the heating relay 12 are turned off.

[0038] Data will continue to be read in a fault state, and the system will return to normal after the read data is normal. For example, the temperature threshold is set to 65°C, and the temperature acquisition line probe is heated and maintained at a high temperature of 65°C. After it is turned on, the battery parameters will be read for self-test and it will be determined whether the battery energy storage system needs high temperature protection, thereby closing the charging relay 7 and the discharging relay 9 to protect the battery energy storage system. At this time, the heating is stopped, and the temperature acquisition probe waits for the temperature to return to the normal value. After the battery energy storage system reads the battery parameters, it will stop the over-temperature protection and turn on the charging relay 7 and the discharging relay 9.

[0039] Reference Figure 2-Figure 3 , also includes an embodiment of an energy storage device, the device is applicable to any control circuit in the above technical solution, including: Circuit board 18; A battery pack 2 is disposed below the circuit board 18; The circuit board 18 is provided with a control board 1, a shunt 4, a first fuse 3, a charging relay 7, a discharging relay 9, a heating relay 12, a buzzer relay 13, a second fuse 11, a DCDC converter 17, a first diode 8, a second diode 14 or a third diode 16.

[0040] It is understandable that the energy storage device provided in the embodiment of the present invention corresponds to the above-mentioned control circuit, and the explanations, examples, beneficial effects and other parts of its relevant contents can refer to the corresponding contents in the control circuit, which will not be repeated here.

[0041] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An energy storage control circuit, characterized in that: include: Control panel (1); The control panel (1) is connected to the battery pack (2); The two ends of the battery pack (2) are connected in parallel with a charging circuit, a discharging circuit, a temperature control circuit and a warning circuit; The on / off of the charging circuit and the discharging circuit are adjusted according to the temperature information of the temperature control circuit, so that the battery pack (2) is heated to a temperature threshold through the temperature control circuit in a low temperature environment.

2. The control circuit according to claim 1, characterized in that: The positive electrode of the battery pack (2) is connected to a first fuse (3), the negative electrode of the battery pack (2) is connected to a shunt (4), and the control panel (1) is also connected to a display screen (5) and a host computer (6).

3. The control circuit according to claim 2, characterized in that: The charging circuit comprises a charging relay (7), the charging relay (7) being connected to the first fuse (3), the other end of the charging relay (7) being connected to the cathode of a first diode (8), the anode of the first diode (8) being connected to the anode of a charger, and the cathode of the charger being connected to the shunt (4).

4. The control circuit according to claim 3, characterized in that: The discharge circuit comprises a discharge relay (9), the discharge relay (9) is connected to the first fuse (3), and the other end of the discharge relay (9) is connected to the shunt (4).

5. The control circuit according to claim 4, characterized in that: One end of the discharge relay (9) connected to the shunt (4) is connected to a normally open synchronous switch (10), and the normally open synchronous switch (10) is connected to the positive electrode and the negative electrode of the discharge end.

6. The control circuit according to claim 4, characterized in that: The temperature control circuit comprises a second fuse (11), one side of the second fuse (11) is connected to the positive electrode of the first diode (8), the other side of the second fuse (11) is connected to a heating relay (12), the other end of the heating relay (12) is connected to a heating port, and the temperature is controlled to rise to a temperature threshold through the heating relay (12).

7. The control circuit according to claim 6, characterized in that: The warning circuit comprises a buzzer relay (13), one end of the buzzer relay (13) is connected to the first fuse (3), and the other end of the buzzer relay (13) is connected to a buzzer port.

8. The control circuit according to claim 7, characterized in that: The first fuse (3) is connected to the charging relay (7) at one side and is also connected to the positive electrode of the second diode (14), the negative electrode of the second diode (14) is connected to the control switch (15), the other end of the control switch (15) is connected to the negative electrode of the third diode (16), and the positive electrode of the third diode (16) is connected to the positive electrode of the charger; The anode of the second diode (14) is connected to the buzzer relay (13).

9. The control circuit according to claim 8, characterized in that: The cathodes of the shunt (4) and the third diode (16) are connected to a DCDC converter (17), and the anode and the grounding terminal of the DCDC converter (17) are connected to the control board (1); Both ends of the coils of the charging relay (7), the discharging relay (9), the heating relay (12) and the buzzer relay (13) are connected to the control board (1).

10. An energy storage device, characterized in that: The energy storage device is applicable to any control circuit in claims 1 to 9, including: Circuit board (18); A battery pack (2) is arranged below the circuit board (18); The circuit board (18) is provided with a control board (1), a shunt (4), a first fuse (3), a charging relay (7), a discharging relay (9), a heating relay (12), a buzzer relay (13), a second fuse (11), a DCDC converter (17), a first diode (8), a second diode (14) or a third diode (16).

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