An intelligent lithium battery system

Abstract

The present invention discloses an intelligent lithium battery system, comprising: at least one battery module, a temperature monitoring device, a voltage monitoring device, an equalizing device, a current monitoring device, an intelligent control device, and a fire extinguishing device; the intelligent control device is connected to the temperature monitoring device, the voltage monitoring device, the current monitoring device, and the equalizing device; the intelligent control device is used to control the time-sharing operation of the battery module and the equalizing device; when the voltage, current, and / or temperature of the lithium battery are abnormal, an alarm is issued and the battery module and the equalizing device are shut down; and when a fire occurs, the fire extinguishing device is triggered to extinguish the fire based on the voltage, current, and / or temperature of the lithium battery. The present invention can reduce the occurrence of accidents such as explosions and fires caused by lithium batteries, thereby ensuring the safety of public life and corporate property.

Description

Technical Field

[0001] The present invention belongs to the field of lithium batteries, and in particular relates to an intelligent lithium battery system. Background Art

[0002] In recent years, the electric vehicle and new energy power generation industries have greatly promoted the development of battery energy storage and power supply technologies, ushering in a period of large-scale and widespread application of lithium batteries.

[0003] However, with the large-scale and widespread application of lithium batteries, accidents such as explosions and fires caused by lithium batteries occur frequently, seriously affecting the safety of public life and corporate property. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides an intelligent lithium battery system.

[0005] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0006] An intelligent lithium battery system, comprising: at least one battery module, a temperature monitoring device, a voltage monitoring device, an equalization device, a current monitoring device, an intelligent control device, and a fire extinguishing device;

[0007] The battery module comprises a plurality of lithium batteries connected in series;

[0008] The temperature monitoring device is used to monitor the temperature of the environment where the lithium battery is located;

[0009] The voltage monitoring device is used to monitor the voltage of the lithium battery;

[0010] The balancing device is configured to provide a battery balancing function for the at least one battery module;

[0011] The current monitoring device is used to monitor the current of the lithium battery;

[0012] The intelligent control device is connected to the temperature monitoring device, the voltage monitoring device, the current monitoring device and the balancing device;

[0013] The intelligent control device is used to control the time-sharing operation of the battery module and the balancing device; to issue an alarm and shut down the battery module and the balancing device when the voltage, current and / or temperature of the lithium battery are abnormal; to determine whether a fire has occurred based on the voltage, current and / or temperature of the lithium battery, and to trigger the fire extinguishing device to extinguish the fire when a fire has occurred.

[0014] Optionally, the battery module includes a plurality of battery modules; the plurality of battery modules are connected in series; and the balancing device is specifically used to provide a battery balancing function for the plurality of battery modules.

[0015] Optionally, the balancing device includes:

[0016] Charge and discharge unit;

[0017] A positive switch pair is connected in series between the positive electrode of the lithium battery and the positive electrode of the charge and discharge unit; the positive switch pair includes: a high-frequency MOS switch and a low-frequency MOS switch with their sources interconnected;

[0018] A negative electrode switch pair is connected in series between the negative electrode of the lithium battery and the negative electrode of the charge and discharge unit; the negative electrode switch pair includes: a high-frequency MOS switch and a low-frequency MOS switch with interconnected drain electrodes;

[0019] A first combination unit is connected in series between the positive switch pair and the positive electrode of the charge and discharge unit; the first combination unit includes a resistor element and a relay; the resistor element and the relay are connected in series;

[0020] A second assembly unit is connected in series between the negative electrode switch pair and the negative electrode of the charge and discharge unit; the second assembly unit includes: an inductor element and a high-frequency switch element; the inductor element and the high-frequency switch element are connected in series; the high-frequency switch element is a MOS transistor; the first assembly unit and the second assembly unit are connected in parallel;

[0021] a first reverse-biased diode, wherein the anode of the diode is connected to the path between the cathode switch pair and the cathode of the charge-discharge unit, and the cathode of the diode is connected to the path between the cathode switch pair and the first combination unit;

[0022] a second reverse-biased diode, the anode of which is connected to the path between the cathode switch pair and the cathode of the charge-discharge unit, and the cathode of which is connected to the path between the inductor element and the high-frequency switch element;

[0023] In which, the intelligent control device configures the switching states of the positive switch pair, the negative switch pair and the high-frequency switching element so that any lithium battery can discharge to the charging and discharging unit through the first combination unit and the second combination unit, or be charged by the charging and discharging unit through the first combination unit and the second combination unit.

[0024] Optionally, the intelligent control device controls the battery module and the balancing device to work in a time-sharing manner, including:

[0025] When the battery module is connected to a load, all positive switch pairs, all negative switch pairs and the high-frequency switch element are turned off to operate the battery module;

[0026] When the battery module is not connected to a load:

[0027] Turning off the high-frequency switching element, driving the high-frequency MOS switch in the positive switch pair and the negative switch pair connected to an overvoltage lithium battery with a PWM signal, and simultaneously turning off the low-frequency MOS switch in the positive switch pair and the negative switch pair connected to the overvoltage lithium battery, so that the overvoltage lithium battery discharges to the charging and discharging unit through the first combination unit and the second combination unit;

[0028] Alternatively, the high-frequency switching element is driven by a PWM signal to turn on the low-frequency MOS switch in the positive switch pair and the negative switch pair connected to an undervoltage lithium battery, and at the same time turn off the high-frequency MOS switch in the positive switch pair and the negative switch pair connected to the undervoltage lithium battery, so that the undervoltage lithium battery is charged by the charging and discharging unit through the first combination unit and the second combination unit.

[0029] Optionally, the overvoltage lithium battery is the lithium battery with the highest voltage in the battery module; the undervoltage lithium battery is the lithium battery with the lowest voltage in the battery module.

[0030] Optionally, the intelligent control device is further used to:

[0031] For any overvoltage lithium battery, calculate and control the time for it to discharge into the charge and discharge unit according to its voltage and the initial current when discharging into the charge and discharge unit;

[0032] For any undervoltage lithium battery, the time for it to be charged by the charging and discharging unit is calculated and controlled according to the initial current when the voltage of the battery is charged by the charging and discharging unit.

[0033] Optionally, the overvoltage lithium battery is the lithium battery with the highest voltage in the battery module;

[0034] The intelligent control device calculates and controls the discharge time of the lithium battery with the highest voltage to the charge and discharge unit according to the voltage of the lithium battery and the current when the lithium battery is discharged to the charge and discharge unit, including:

[0035] Obtaining the voltage of each lithium battery in the battery module except the lithium battery with the highest voltage, and calculating the voltage average;

[0036] According to the voltage difference between the voltage of the lithium battery with the highest voltage and the voltage average, and utilizing the initial current when the lithium battery with the highest voltage discharges to the charge and discharge unit, the discharge time of the overvoltage lithium battery to the charge and discharge unit is calculated and controlled.

[0037] Optionally, the undervoltage lithium battery is the lithium battery with the lowest voltage in the battery module; the intelligent control device calculates and controls the charging time of the lithium battery with the lowest voltage by the charging and discharging unit according to the current when the lithium battery is charged by the charging and discharging unit, including:

[0038] Obtaining the voltage of each lithium battery in the battery module except the lithium battery with the lowest voltage, and calculating the voltage average;

[0039] According to the voltage difference between the voltage of the lithium battery with the lowest voltage and the voltage average, and utilizing the initial current when the lithium battery with the lowest voltage is charged by the charge and discharge unit, the time for the lithium battery with the lowest voltage to be charged by the charge and discharge unit is calculated and controlled.

[0040] Optionally, the system is applied to a charging cabinet or a charging pile.

[0041] Optionally, the system further comprises: an infrared video monitoring module and a communication module;

[0042] The infrared video monitoring module is used to perform video monitoring on the battery module and send an alarm to the intelligent control device when a fire is detected;

[0043] The intelligent control device is further configured to shut down the battery module and the balancing device, trigger the fire extinguishing device to extinguish the fire, and report the fire accident through the communication module upon receiving an alarm from the infrared video monitoring module.

[0044] The intelligent lithium battery system provided by the present invention includes a temperature monitoring device, a voltage monitoring device, a current monitoring device, a balancing device, a fire extinguishing device, and an intelligent control device. The intelligent control device controls the battery modules and the balancing device to operate in a time-sharing manner, thereby providing battery balancing for the battery modules when the battery modules are not connected to a load. This prevents the large differences between lithium batteries that occur with the use of the battery modules. When lithium batteries have large differences, charging or discharging the battery modules can easily lead to uncontrolled charging and discharging, which can in turn cause battery fires and explosions. Therefore, by incorporating a balancing device into the system, the present invention can eliminate the unsafe factors caused by uneven battery charging and discharging, thereby reducing safety risks. Furthermore, the intelligent control device of the present invention can also issue an alarm when the voltage, current, and / or temperature of the lithium battery are abnormal, thereby providing early warning and reducing the probability of accidents such as explosions and fires. Furthermore, the intelligent control device can also determine whether a fire has occurred based on the voltage, current, and / or temperature of the lithium battery, and trigger the fire extinguishing device to extinguish the fire when a fire occurs, thereby eliminating the damage caused by the fire and reducing further losses.

[0045] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a schematic structural diagram of an intelligent lithium battery system provided by an embodiment of the present invention;

[0047] Figure 2 yes Figure 1 A schematic structural diagram of the balancing device in the system;

[0048] Figure 3 yes Figure 2 The equalization device shown enables a lithium battery to discharge to the charge and discharge unit during a period of time.

[0049] Figure 4 yes Figure 2 The equalization device shown enables a lithium battery to discharge to the charging and discharging unit during another period of time.

[0050] Figure 5 yes Figure 2 The equalization device shown enables a lithium battery to discharge to the charge and discharge unit during another period of time.

[0051] Figure 6 yes Figure 2 The equalization device shown enables the charge and discharge unit to follow the current path for a period of time during the charging process of a lithium battery;

[0052] Figure 7 yes Figure 2 The equalization device shown enables the charge and discharge unit to follow the current path during another period of time during the charging process of a lithium battery;

[0053] Figure 8 yes Figure 2 The balancing device shown enables the charge and discharge unit to provide a current path for a period of time during the charging process of a lithium battery. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below with reference to specific examples, but the embodiments of the present invention are not limited thereto.

[0055] In order to reduce the occurrence of accidents such as explosions and fires caused by lithium batteries and ensure the safety of public life and corporate property, an embodiment of the present invention provides an intelligent lithium battery system. Figure 1 As shown, the system includes: at least one battery module, a temperature monitoring device T, a voltage monitoring device V, a balancing device E, a current monitoring device I, an intelligent control device IC and a fire extinguishing device.

[0056] Each battery module consists of multiple lithium-ion batteries connected in series, which are used to charge external loads, such as electric vehicles, electric motorcycles, electric bicycles, or electronic devices.

[0057] The temperature monitoring device is used to monitor the temperature of the environment where the lithium battery is located.

[0058] In practical applications, the temperature monitoring device includes multiple temperature sensors, which can be arranged near the battery module to monitor the temperature of the environment surrounding the lithium batteries in the battery module. The number of temperature sensors can be determined based on the size of the battery module. For example, a larger battery module may require more temperature sensors, while a smaller one may be sufficient.

[0059] The voltage monitoring device is used to monitor the voltage of the lithium battery.

[0060] like Figure 1 As shown, the voltage monitoring device monitors the voltage of each lithium battery.

[0061] In practical applications, the voltage detection device is preferably a voltage sampling circuit, which facilitates system integration and miniaturization. Of course, it is also possible to use a directly purchased voltage detection module, and the embodiment of the present invention does not limit the voltage monitoring device.

[0062] The balancing device is used to provide battery balancing function for each battery module.

[0063] In practical applications, under the premise of being able to achieve an effective balancing effect, the balancing device may include an active balancing circuit or a passive balancing circuit, which is acceptable.

[0064] Furthermore, if battery module life is a high priority, an active balancing circuit is preferred. This is because passive balancing circuits achieve cell balancing by using energy-consuming components to dissipate battery energy, resulting in energy waste and reducing the total dischargeable energy of the battery module. Active balancing circuits, on the other hand, achieve cell balancing by transferring energy between lithium-ion cells, making them more suitable for applications where battery module life is a high priority.

[0065] A current monitoring device, used to monitor the current of the lithium battery;

[0066] like Figure 1 As shown, the current monitoring device monitors the current of each lithium battery.

[0067] In practical applications, the current detection device is preferably a current sampling circuit, which facilitates system integration and miniaturization. Of course, it is also possible to use a directly purchased current detection module, and the embodiment of the present invention does not limit the current monitoring device.

[0068] like Figure 1As shown, the intelligent control device is connected to the temperature monitoring device, voltage monitoring device, current monitoring device, and balancing device. This intelligent control device is used to control the time-sharing operation of the battery module and balancing device; when the voltage, current, and / or temperature of the lithium battery are abnormal, an alarm is issued and the battery module and balancing device are shut down; based on the voltage, current, and / or temperature of the lithium battery, whether there is a fire is detected, and when a fire occurs, the fire extinguishing device is triggered to extinguish the fire.

[0069] It is understandable that when the battery module is working, it needs to provide charging services for the external load. At this time, if the balancing device is enabled, the balancing device will charge or discharge the lithium batteries in the battery module. Therefore, the balancing device and the battery module do not work at the same time.

[0070] Furthermore, the intelligent control device monitors the voltage, current, and temperature of the lithium battery, providing real-time information on its operating conditions and issuing alerts when voltage, current, and / or temperature are abnormal. For example, if it detects an abnormal increase in current, an abnormal decrease in voltage, or an abnormal increase in temperature, the intelligent control device will issue an alert, prompting personnel to conduct an inspection and identify risks in advance.

[0071] Generally speaking, before a fire occurs, the voltage and current of the lithium battery that caused the fire will be abnormal, such as the voltage drops and the current first increases and then decreases. Therefore, if the voltage and current data of this situation are monitored, combined with the temperature monitored by the temperature sensor, it can be determined whether a fire has occurred in the battery module, thereby triggering the fire extinguishing device to extinguish the fire. This can avoid false alarms caused by abnormalities in single monitoring data due to interference or link instability. In addition, the embodiment of the present invention does not limit the fire extinguishing device. If it itself contains an electrical control chip or circuit, the intelligent control device only needs to provide it with a trigger signal. If the fire extinguishing device does not contain such an electrical control chip or circuit, it is only necessary to install a mechanical trigger mechanism between the intelligent control device and the fire extinguishing device. The embodiment of the present invention also does not limit this.

[0072] The intelligent lithium battery system provided by an embodiment of the present invention includes a temperature monitoring device, a voltage monitoring device, a current monitoring device, a balancing device, a fire extinguishing device, and an intelligent control device. The intelligent control device controls the time-sharing operation of the battery modules and the balancing device, thereby providing battery balancing for the battery modules when the battery modules are not connected to a load. This prevents the large differences between lithium batteries that occur with the use of the battery modules. When lithium batteries have large differences, charging or discharging the battery modules can easily lead to uncontrolled charging and discharging, which can in turn cause battery fires and explosions. Therefore, by incorporating a balancing device into the system, the embodiments of the present invention can eliminate the unsafe factors caused by uneven battery charging and discharging, thereby reducing safety risks. Furthermore, the intelligent control device in the embodiments of the present invention can also issue an alarm when the voltage, current, and / or temperature of the lithium battery are abnormal, thereby providing early warning and reducing the probability of accidents such as explosions and fires. Furthermore, the intelligent control device can also determine whether a fire has occurred based on the voltage, current, and / or temperature of the lithium battery, and trigger the fire extinguishing device to extinguish the fire when a fire occurs, thereby eliminating the damage and reducing further losses.

[0073] In one embodiment, when the system includes multiple battery modules, the multiple battery modules are connected in series; accordingly, the balancing device is specifically configured to provide a battery balancing function for the battery modules connected in series.

[0074] Figure 2 An example of an equalizing device is shown in FIG. Figure 2 As shown in , it includes: a charge and discharge unit, a positive switch pair 1, a negative switch pair 2, a first combination unit 3, a second combination unit 4, a first reverse biased diode D1 and a second reverse biased diode D2.

[0075] The charging and discharging unit may be a supercapacitor or a lithium battery independent of the battery module. Figure 2 In the following figures, the symbol I is used to represent the lithium battery of the battery module.

[0076] The positive switch pair 1 is connected in series between the positive electrode of the lithium battery and the positive electrode of the charge and discharge unit; the positive switch pair 1 includes: a high-frequency MOS switch and a low-frequency MOS switch with their sources interconnected.

[0077] The negative electrode switch pair 2 is connected in series between the negative electrode of the lithium battery and the negative electrode of the charge and discharge unit; the negative electrode switch pair 2 includes: a high-frequency MOS switch and a low-frequency MOS switch with interconnected drains.

[0078] The first combination unit 3 is connected in series between the positive switch pair 1 and the positive electrode of the charge and discharge unit. The first combination unit 3 includes a resistor R1 and a relay SW. The resistor R1 and the relay SW are connected in series.

[0079] The second combination unit 4 is connected in series between the negative electrode switch pair 2 and the negative electrode of the charge and discharge unit; the second combination unit 4 includes: an inductor element L1 and a high-frequency switch element SB; the inductor element L1 and the high-frequency switch element SB are connected in series; the high-frequency switch element SB is a MOS tube; the first combination unit 3 and the second combination unit 4 are connected in parallel.

[0080] The anode of the first reverse biased diode D1 is connected between the negative switch pair 2 and the negative electrode of the charge and discharge unit, and the cathode is connected between the positive switch pair 1 and the first combination unit 3;

[0081] The anode of the second reverse-biased diode D2 is connected between the cathode switch pair 2 and the cathode of the charge-discharge unit, and the cathode is connected between the inductor element L1 and the high-frequency switch element SB.

[0082] Based on the above balancing transposition, the intelligent control device controls the battery module and the balancing device to work in time-sharing mode, including:

[0083] When the battery module is connected to a load, the intelligent control device turns off all positive switch pairs 1, all negative switch pairs 2, and the high-frequency switch element SB, allowing the battery module to operate;

[0084] When the battery module is not connected to a load, the intelligent control device configures the switching states of the positive switch pair 1, the negative switch pair 2 and the high-frequency switch element SB to operate the balancing device, that is, to perform battery balancing using the balancing device.

[0085] In the embodiment of the present invention, based on Figure 2 The balancing device shown in the figure, the intelligent control device can configure the switching states of the positive switch pair 1, the negative switch pair 2 and the high-frequency switch element SB, so that any lithium battery can discharge to the charging and discharging unit through the first combination unit 3 and the second combination unit 4, or the charged and discharged unit can charge it through the first combination unit 3 and the second combination unit 4.

[0086] In practical applications, the purpose of active balancing is to transfer the power of lithium batteries with high voltage to lithium batteries with low voltage. Figure 2In the balancing device shown, the intelligent control device turns off the high-frequency switching element SB and uses a PWM (pulse width modulation) signal to drive the high-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to the overvoltage lithium battery, while simultaneously turning off the low-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to the overvoltage lithium battery. This allows the overvoltage lithium battery to discharge to the charge-discharge unit through the first combination unit 3 and the second combination unit 4. Alternatively, the intelligent control device drives the high-frequency switching element SB with a PWM signal to turn on the low-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to the undervoltage lithium battery, while simultaneously turning off the high-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to the undervoltage lithium battery. This allows the undervoltage lithium battery to be charged by the charge-discharge unit through the first combination unit 3 and the second combination unit 4.

[0087] Specifically, see Figure 3 As shown, assuming that the lithium battery I1 is an overvoltage lithium battery, the high-frequency switch element SB is turned off, and the high-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to I1 are driven by the PWM signal, that is, Figure 3 HP and HN in the circuit simultaneously turn off the low-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 connected to I1, that is, Figure 3 LP and LN in the circuit; HP and HN are driven by PWM signals, so they are periodically turned on and off. During the conduction interval of HP and HN, the current flows from the positive electrode of I1, through the positive switch pair 1, to the first combination unit 3 and the second combination unit 4; because the relay is initially closed, the current flows through the second combination unit 4 to the positive electrode of the charge-discharge unit, and then the current flows from the negative electrode of the charge-discharge unit back to the negative electrode of I1, realizing the discharge of I1 to the charge-discharge unit. The current path during the discharge process is as follows: Figure 3 In the off-time of HP and HN, the inductor element L1 in the second combination unit continues to flow, so the current can continue to flow to the charge and discharge unit, as shown in FIG. Figure 4 shown.

[0088] Among them, although the low-frequency MOS switches LP and LN and the high-frequency switch element SB are turned off, since they are all MOS tubes and MOS tubes have parasitic diodes, the MOS tubes allow current to flow along the direction of the parasitic diode bias.

[0089] As I1 continues to discharge to the charge and discharge unit, the voltage difference between them gradually decreases. At a certain moment, the relay is turned on. At this time, I1 directly discharges to the charge and discharge unit through the first combination unit 3. Figure 5 As shown in the figure, resistor R1 and the relay are connected in series to limit the current.

[0090] See also Figure 6 As shown, assuming that the lithium battery I n If it is an undervoltage lithium battery, the high-frequency switching element SB is driven by a PWM signal to open I n The low-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 are connected, that is, the low-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 are turned on. Figure 6 LP and LN in, while closing I n The high-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 are connected, that is, the high-frequency MOS switches in the positive switch pair 1 and the negative switch pair 2 are closed. Figure 6 HP and HN in the circuit; Since SB is driven by PWM signal, it is periodically turned on and off; In the conduction interval of SB, current flows out from the positive electrode of the charge and discharge unit to the first combination unit 1 and the second combination unit 2; Since the relay SW in the first combination unit 1 is closed at the beginning, the current flows through the second combination unit 4 and the positive switch pair 1 to I n The positive electrode, then from I n The negative electrode flows out and returns to the negative electrode of the charge and discharge unit, realizing the charge and discharge unit to I n Charging, the current path during charging is shown in Figure 6 In the conduction interval of SB, the inductor in the second combination unit continues to flow, so the charge and discharge unit can continue to supply current to I n Charging, the current path during charging is shown in Figure 7 Indicated by the grey dashed line.

[0091] Among them, although the high-frequency MOS switches HP and HN are turned off, since they are both MOS tubes, current is allowed to flow along the biased direction of their parasitic diodes.

[0092] As the charge and discharge unit continues to n Charging, the voltage difference between them gradually decreases, to a certain moment the relay is turned on, at this time the charging and discharging unit directly to I through the first combination unit 1 n Charging, such as Figure 8 As shown in Figure 2, resistor R1 also plays a role in current limiting.

[0093] Based on Figures 3 to 8 As can be seen from the description, the embodiment of the present invention uses a pair of high-frequency MOS switches and low-frequency MOS switches interconnected by the source, and uses a pair of high-frequency MOS switches and low-frequency MOS switches interconnected by the drain. Their function is not only to open or close the charge / discharge path between the lithium battery and the charge / discharge unit, but more importantly, it can avoid the short circuit between the positive and negative electrodes of the lithium battery when the charge / discharge mode is switched.

[0094] Preferably, when the balancing module realizes battery balancing for the battery module, the overvoltage lithium battery selected each time may be the lithium battery with the highest voltage in the battery module; the undervoltage lithium battery selected each time may be the lithium battery with the lowest voltage in the battery module.

[0095] For example, the intelligent control device can periodically select the lithium battery with the highest voltage to discharge to the charge and discharge unit. When the lithium battery is discharged, the intelligent control device continues to select the lithium battery with the lowest voltage to charge it within the same cycle. In this way, the charge and discharge unit is used as a bridge to build an energy transmission path between the overvoltage lithium battery and the undervoltage lithium battery, effectively achieving battery balancing.

[0096] Furthermore, in order to improve the balancing efficiency, the intelligent control device can also calculate and control the time for the overvoltage lithium battery to discharge into the charge and discharge unit based on its voltage and the initial current when discharging into the charge and discharge unit; correspondingly, for the undervoltage lithium battery, the intelligent control device can calculate and control the time for it to be charged by the charge and discharge unit based on its voltage and the initial current when charging into the charge and discharge unit.

[0097] Taking the overvoltage lithium battery with the highest voltage as an example, for the overvoltage lithium battery, the intelligent control device can first obtain the voltage of each lithium battery in the battery module except the overvoltage lithium battery, and calculate the voltage average; then, based on the voltage difference between the voltage of the overvoltage lithium battery and the voltage average, and using the initial current when the overvoltage lithium battery discharges to the charge and discharge unit, calculate and control the discharge time of the overvoltage lithium battery to the charge and discharge unit.

[0098] The amount of electricity can be obtained by integrating the initial current over time, so the time of current integration can be inferred based on the linear relationship between the amount of electricity and the voltage.

[0099] Similarly, taking the undervoltage lithium battery with the lowest voltage as an example, for the undervoltage lithium battery, the intelligent control device can first obtain the voltage of each lithium battery in the battery module except the undervoltage lithium battery, and calculate the voltage average; then, based on the voltage difference between the voltage of the undervoltage lithium battery and the voltage average, and using the initial current when the undervoltage lithium battery is charged by the charge and discharge unit, calculate and control the time for the undervoltage lithium battery to be charged by the charge and discharge unit.

[0100] It is understandable that by calculating the charge and discharge time and thereby controlling the discharge or charge time of the lithium battery according to the time, the battery module can be balanced more quickly.

[0101] Generally speaking, considering that the battery specifications in a battery module are generally consistent and the voltage difference between them is not too large, a small-capacity charge and discharge unit can be used to achieve battery balancing. Preferably, the capacity of the charge and discharge unit can be selected to be 1% to 10% of the rated capacity of the lithium battery.

[0102] In one embodiment, the smart lithium battery system provided by the embodiment of the present invention can be applied to a charging cabinet or a charging pile.

[0103] On this basis, since the charging cabinet or charging pile does not have a high demand for system miniaturization, in order to further ensure safety, the system can also include an infrared video monitoring module and a communication module.

[0104] Among them, the infrared video monitoring module is used to perform video monitoring of the battery module and send an alarm to the intelligent control device when a fire is detected; accordingly, the intelligent control device can also be used to shut down the battery module and the balancing device, trigger the fire extinguishing device to extinguish the fire, and report the fire accident through the communication module when receiving the alarm sent by the infrared video monitoring module.

[0105] Therefore, through temperature and image monitoring methods, fires can be accurately detected and extinguished at the first time, and relevant personnel can be notified to handle the situation.

[0106] It should be noted that the terms "first," "second," and the like are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure.

[0107] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described can be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0108] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art may understand and implement other variations of the disclosed embodiments by reviewing the drawings and the disclosed content. In the description of the present invention, the word "comprising" does not exclude other components or steps, "one" or "a" does not exclude multiple situations, and "multiple" means two or more, unless otherwise clearly and specifically limited. In addition, certain measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0109] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0110] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. An intelligent lithium battery system, characterized in that: include: At least one battery module, a temperature monitoring device, a voltage monitoring device, a balancing device, a current monitoring device, an intelligent control device, and a fire extinguishing device; The battery module comprises a plurality of lithium batteries connected in series; The temperature monitoring device is used to monitor the temperature of the environment where the lithium battery is located; The voltage monitoring device is used to monitor the voltage of the lithium battery; The balancing device is configured to provide a battery balancing function for the at least one battery module; The current monitoring device is used to monitor the current of the lithium battery; The intelligent control device is connected to the temperature monitoring device, the voltage monitoring device, the current monitoring device and the balancing device; The intelligent control device is used to control the battery module and the balancing device to work in a time-sharing manner; when the voltage, current and / or temperature of the lithium battery are abnormal, an alarm is issued and the battery module and the balancing device are shut down; Determine whether a fire occurs based on the voltage, current and / or temperature of the lithium battery, and trigger the fire extinguishing device to extinguish the fire when a fire occurs; The balancing device comprises: Charge and discharge unit; A positive switch pair is connected in series between the positive electrode of the lithium battery and the positive electrode of the charge and discharge unit; the positive switch pair includes: a high-frequency MOS switch and a low-frequency MOS switch with their sources interconnected; A negative electrode switch pair is connected in series between the negative electrode of the lithium battery and the negative electrode of the charge and discharge unit; the negative electrode switch pair includes: a high-frequency MOS switch and a low-frequency MOS switch with interconnected drain electrodes; A first combination unit is connected in series between the positive switch pair and the positive electrode of the charge and discharge unit; the first combination unit includes a resistor element and a relay; the resistor element and the relay are connected in series; A second assembly unit is connected in series between the negative electrode switch pair and the negative electrode of the charge and discharge unit; the second assembly unit includes: an inductor element and a high-frequency switch element; the inductor element and the high-frequency switch element are connected in series; the high-frequency switch element is a MOS transistor; the first assembly unit and the second assembly unit are connected in parallel; a first reverse-biased diode, wherein the anode of the diode is connected to the path between the cathode switch pair and the cathode of the charge-discharge unit, and the cathode of the diode is connected to the path between the cathode switch pair and the first combination unit; a second reverse-biased diode, the anode of which is connected to the path between the cathode switch pair and the cathode of the charge-discharge unit, and the cathode of which is connected to the path between the inductor element and the high-frequency switch element; In which, the intelligent control device configures the switching states of the positive switch pair, the negative switch pair and the high-frequency switching element so that any lithium battery can discharge to the charging and discharging unit through the first combination unit and the second combination unit, or be charged by the charging and discharging unit through the first combination unit and the second combination unit.

2. The intelligent lithium battery system according to claim 1, characterized in that: The battery modules include a plurality of battery modules connected in series; the balancing device is specifically used to provide a battery balancing function for the plurality of battery modules.

3. The intelligent lithium battery system according to claim 1, characterized in that: The intelligent control device controls the battery module and the balancing device to work in a time-sharing manner, including: When the battery module is connected to a load, all positive switch pairs, all negative switch pairs and the high-frequency switch element are turned off to operate the battery module; When the battery module is not connected to a load: Turning off the high-frequency switching element, driving the high-frequency MOS switch in the positive switch pair and the negative switch pair connected to an overvoltage lithium battery with a PWM signal, and simultaneously turning off the low-frequency MOS switch in the positive switch pair and the negative switch pair connected to the overvoltage lithium battery, so that the overvoltage lithium battery discharges to the charging and discharging unit through the first combination unit and the second combination unit; Alternatively, the high-frequency switching element is driven by a PWM signal to turn on the low-frequency MOS switch in the positive switch pair and the negative switch pair connected to an undervoltage lithium battery, and at the same time turn off the high-frequency MOS switch in the positive switch pair and the negative switch pair connected to the undervoltage lithium battery, so that the undervoltage lithium battery is charged by the charging and discharging unit through the first combination unit and the second combination unit.

4. The intelligent lithium battery system according to claim 3, characterized in that: The overvoltage lithium battery is the lithium battery with the highest voltage in the battery module; the undervoltage lithium battery is the lithium battery with the lowest voltage in the battery module.

5. The intelligent lithium battery system according to claim 3, characterized in that: The intelligent control device is further used for: For any overvoltage lithium battery, calculate and control the time for it to discharge into the charge and discharge unit according to its voltage and the initial current when discharging into the charge and discharge unit; For any undervoltage lithium battery, the time for it to be charged by the charging and discharging unit is calculated and controlled according to the initial current when the voltage of the battery is charged by the charging and discharging unit.

6. The intelligent lithium battery system according to claim 5, characterized in that: The overvoltage lithium battery is the lithium battery with the highest voltage in the battery module; The intelligent control device calculates and controls the discharge time of the lithium battery with the highest voltage to the charge and discharge unit according to the voltage of the lithium battery and the current when the lithium battery is discharged to the charge and discharge unit, including: Obtaining the voltage of each lithium battery in the battery module except the lithium battery with the highest voltage, and calculating the voltage average; According to the voltage difference between the voltage of the lithium battery with the highest voltage and the voltage average, and utilizing the initial current when the lithium battery with the highest voltage discharges to the charge and discharge unit, the discharge time of the overvoltage lithium battery to the charge and discharge unit is calculated and controlled.

7. The intelligent lithium battery system according to claim 5, characterized in that: The undervoltage lithium battery is the lithium battery with the lowest voltage in the battery module; the intelligent control device calculates and controls the charging time of the lithium battery with the lowest voltage by the charging and discharging unit according to the current when the undervoltage lithium battery is charged by the charging and discharging unit, including: Obtaining the voltage of each lithium battery in the battery module except the lithium battery with the lowest voltage, and calculating the voltage average; According to the voltage difference between the voltage of the lithium battery with the lowest voltage and the voltage average, and utilizing the initial current when the lithium battery with the lowest voltage is charged by the charge and discharge unit, the time for the lithium battery with the lowest voltage to be charged by the charge and discharge unit is calculated and controlled.

8. The intelligent lithium battery system according to any one of claims 1 to 7, characterized in that: The system is applied to a charging cabinet or a charging pile.

9. The intelligent lithium battery system according to claim 8, characterized in that: Also includes: Infrared video surveillance module and communication module; The infrared video monitoring module is used to perform video monitoring on the battery module and send an alarm to the intelligent control device when a fire is detected; The intelligent control device is further configured to shut down the battery module and the balancing device, trigger the fire extinguishing device to extinguish the fire, and report the fire accident through the communication module upon receiving an alarm from the infrared video monitoring module.

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