Buoy battery compartment overcharge and overdischarge protection circuit

Abstract

The invention provides an over-charge and over-discharge protection circuit for a buoy battery compartment, and belongs to the technical field of battery safety. The buoy battery cabin overcharge and overdischarge protection circuit comprises a solar panel, a power regulation circuit, a charge protection switch, a lithium battery, a discharge protection switch, a load and a control circuit of an offshore buoy system. The control circuit comprising the control signal generating circuit and the threshold value generating circuit is used for carrying out over-charge and over-discharge protection on the buoy battery cabin, the structure of the battery over-charge and over-discharge protection system can be simplified, the size is reduced, and it is guaranteed that the structure of the battery over-charge and over-discharge protection system can be applied to the specific technical field with the limited structural space; meanwhile, through the design of the threshold generation circuit, the threshold adjustment mode is simplified, and the universality of the lithium battery over-charge and over-discharge protection circuit is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery safety, and in particular relates to an overcharge and overdischarge protection circuit for a buoy battery compartment. Background Art

[0002] Lithium batteries, currently a common mobile power source, have been widely used in various technological fields, including consumer electronics, industrial equipment, and new energy equipment. However, overcharging a lithium battery can lead to excessive delithiation of the positive electrode material, deposition of metallic lithium on the negative electrode to form dendrites, and increased internal pressure, accelerating battery aging. Overdischarging a lithium battery can also lead to dissolution of the negative electrode copper foil, irreversible capacity loss, and damage to the solid electrolyte interface, resulting in a decrease in battery performance. Therefore, it is necessary to control the charge and discharge of lithium batteries. In the prior art, two different protection control circuit systems are usually adopted, namely, an overcharge protection control circuit system and an over-discharge protection control circuit system, to protect lithium batteries from overcharging and over-discharging respectively. That is, when the lithium battery is overcharged, the overcharge protection control circuit system generates an overcharge control signal to protect the lithium battery; when the lithium battery is over-discharged, the over-discharge protection control circuit system generates an over-discharge control signal to protect the lithium battery; in addition, the existing lithium battery protection system also requires two threshold generation circuits to generate the overcharge threshold and the over-discharge threshold respectively, resulting in a bulky structure of the battery overcharge and over-discharge protection system, which is difficult to apply to specific technical fields with limited structural space, such as offshore buoy systems; and since two threshold generation circuits are required, the overcharge threshold and the over-discharge threshold need to be adjusted separately, the adjustment process is relatively complicated, and it is difficult to improve the versatility of the lithium battery overcharge and over-discharge protection circuit. Summary of the Invention

[0003] In order to solve the above problems existing in the prior art, the present invention proposes a buoy battery compartment overcharge and over-discharge protection circuit to solve the problems of bulky structure and poor versatility of the battery overcharge and over-discharge protection system in the prior art.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a buoy battery compartment overcharge and over-discharge protection circuit, comprising a solar panel, a power regulation circuit, a charging protection switch, a lithium battery, a discharge protection switch, a load and a control circuit of an offshore buoy system, wherein the solar panel, the power regulation circuit, the charging protection switch, the lithium battery, the discharge protection switch and the load are connected in sequence; the control circuit is used to detect the voltage of the lithium battery, and when the voltage of the lithium battery is greater than a first threshold, generates a first control signal, controls the charging protection switch to be disconnected through the first control end, and generates a second control signal when the voltage of the lithium battery is less than a second threshold, controls the discharge protection switch to be disconnected through the second control end, thereby realizing overcharge and over-discharge protection of the buoy battery compartment; the first threshold is greater than the second threshold.

[0005] Furthermore, the control circuit includes a control signal generating circuit and a threshold generating circuit, the threshold generating circuit generates the first threshold and the second threshold, the control signal generating circuit is connected to the output end of the threshold generating circuit, and generates a first control signal or a second control signal according to the first threshold or the second threshold.

[0006] Furthermore, the control signal generating circuit includes a detected battery voltage VB, a diode D1, a switch k1, a resistor R1, an amplifier AMP1 and a logic gate L1. The detected battery voltage VB is connected to the anode of the diode D1 and one end of the switch k1, the cathode of the diode D1 and the other end of the switch k1 are connected to one end of the resistor R1, the other end of the resistor R1 is connected to the output end of the threshold generating circuit, the positive input end of the amplifier AMP1 is connected to one end of the resistor R1, the negative input end of the amplifier AMP1 is connected to the other end of the resistor R1, the output end of the amplifier AMP1 is connected to one input end of the logic gate L1, and the other input end of the logic gate L1 inputs the control signal of the switch k1; the logic gate L1 is an XNOR gate.

[0007] Furthermore, the threshold generation circuit includes a power supply CV, a switch k11, a switch k12, a resistor R11, an adjustable resistor R12, a resistor R13, a resistor R14, a diode D11, a switch Q11, and a capacitor C11. The power supply CV is connected to one end of the switch k11 and one end of the switch k12. The other end of the switch k12 is connected to one end of the capacitor C11, serving as the output end of the threshold generation circuit. The other end of the capacitor C11 is grounded. The other end of the switch k11 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to one end of the adjustable resistor R12, one end of the resistor R14, one end of the switch Q11, and one end of the capacitor C11. The other end of the adjustable resistor R12 is grounded via the resistor R13. The other end of the resistor R14 is connected to the cathode of the diode D11 and the control end of the switch Q11. The anode of the diode D11 and the other end of the switch Q11 are grounded. The diode D11 is a voltage-stabilizing diode.

[0008] Furthermore, the offshore buoy system includes an integrated weather station, an antenna, an atmospheric radiometer, a battery compartment, a temperature probe, a single-point current meter, a navigation light, a solar panel, a wave meter, a float, and a nuclear radiometer.

[0009] The beneficial technical effects of the present invention compared with the prior art are: (1) A control circuit is used to generate an overcharge control signal and an over-discharge control signal, and a threshold generation circuit is used to generate an overcharge threshold and an over-discharge threshold, thereby simplifying the structure of the battery overcharge and over-discharge protection system, reducing the volume, and ensuring that the battery overcharge and over-discharge protection system structure can be applied to specific technical fields with limited structural space; (2) By designing a threshold generation circuit, the threshold adjustment method is simplified and the versatility of the lithium battery overcharge and overdischarge protection circuit is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0011] Figure 1 This is a simplified structural diagram of the marine buoy system of the present invention; Figure 2 This is a simplified structural diagram of the overcharge and over-discharge protection circuit for the buoy battery compartment of the present invention; Figure 3 A structural diagram of a control signal generating circuit of the present invention; Figure 4 This is a structural diagram of the threshold generation circuit of the present invention. DETAILED DESCRIPTION

[0012] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0013] The following first describes the concepts involved in this application with reference to the accompanying drawings. It should be noted that the following description of each concept is intended only to make the content of this application easier to understand and does not limit the scope of protection of this application. At the same time, the embodiments and features in the embodiments of this application can be combined with each other unless there is a conflict. The following detailed description of this application will be made with reference to the accompanying drawings and in conjunction with the embodiments.

[0014] In conjunction with the instructions Figure 1The offshore buoy system of the present invention includes an integrated weather station 1, an antenna 2, an atmospheric radiometer 3, a battery compartment 4, a temperature probe 5, a single-point current meter 6, a navigation light 7, a solar panel 8, a wave meter 9, a float 10, and a nuclear radiation meter 11. The battery compartment 4 houses a lithium battery connected to the solar panel 8. The offshore buoy system utilizes a modular integrated design combining a weather station and multi-parameter sensors (water temperature, wave, and current), meeting the requirements for nuclear emergency parameter collection. The integrated weather station 1, antenna 2, and navigation light 7 are positioned above the offshore buoy system, reducing signal clutter for the antenna 2, preventing the integrated weather station 1 from being soaked by seawater, and extending the indication range of the navigation light 7. Four stainless steel hollow tubes serve as connecting rods to connect the float 10 and the single-point current meter 6. The lower end of the float 10 is designed in a circular structure to ensure excellent wave resistance. The solar panel 8 is installed in a flat pattern, minimizing its footprint and reducing the windward area, thus ensuring the stability of the offshore buoy system. It should also be noted that before the above-mentioned offshore buoy system leaves the factory, it is necessary to simulate the effects of single environmental factors (high and low temperature, humidity, vibration, impact, tilt, swing, salt spray, drop, solar radiation, etc.) and comprehensive environmental factors on the offshore buoy system (temperature and humidity combined, temperature and vibration combined, humidity and vibration combined, etc.) in a laboratory environment, and conduct "temperature-humidity-vibration" tests or "temperature-humidity-swing" tests on the components, parts, circuits, etc. of the offshore buoy system to ensure the normal function of the offshore buoy system and improve the reliability of the offshore buoy system. Figure 2 The buoy battery compartment overcharge and over-discharge protection circuit of the present invention includes a solar panel 8, a power regulation circuit P1, a charging protection switch P2, a lithium battery P3, a discharge protection switch P4, a load P5, and a control circuit P6 of a marine buoy system. The solar panel 8, power regulation circuit P1, charging protection switch P2, lithium battery P3, discharge protection switch P4, and load P5 are connected in sequence. The charging protection switch P2 and the discharge protection switch P4 may be MOS transistors, triodes, etc. The control circuit P6 is used to detect the voltage of the lithium battery P3 and, when the voltage of the lithium battery P3 is greater than a first threshold, generates a first control signal to control the charging protection switch P2 to be disconnected via a first control terminal P61. When the voltage of the lithium battery P3 is less than a second threshold, it generates a second control signal to control the discharge protection switch P4 to be disconnected via a second control terminal P62, thereby implementing overcharge and over-discharge protection for the buoy battery compartment. The first threshold is greater than the second threshold. Because the solar panels in the offshore buoy system are relatively small, power conditioning circuit P1 is preferably a high-ratio boost circuit to ensure rapid charging of the lithium battery. This circuit can include a charge pump, an interleaved parallel boost circuit, a high-frequency step-up transformer, and other components. The voltage of lithium battery P3 can be detected using a resistor divider detection circuit, a voltage follower, or a high-precision ADC chip.

[0015] In conjunction with the instructions Figure 3-4 The control circuit of the present invention includes a control signal generating circuit (see the appendix of the specification Figure 3 ) and threshold generation circuit (see the appendix of the manual Figure 4 ), the threshold generating circuit generates the first threshold and the second threshold, the control signal generating circuit is connected to the output terminal VCC of the threshold generating circuit, and generates a first control signal or a second control signal according to the first threshold or the second threshold.

[0016] The control signal generating circuit includes a detected battery voltage VB, a diode D1, a switch k1, a resistor R1, an amplifier AMP1, and a logic gate L1. The detected battery voltage VB is connected to the anode of the diode D1 and one end of the switch k1. The cathode of the diode D1 and the other end of the switch k1 are connected to one end of the resistor R1. The other end of the resistor R1 is connected to the output of the threshold generation circuit. The positive input of the amplifier AMP1 is connected to one end of the resistor R1, the negative input of the amplifier AMP1 is connected to the other end of the resistor R1, the output of the amplifier AMP1 is connected to one input of the logic gate L1, and the other input of the logic gate L1 receives the control signal of the switch k1. The logic gate L1 is an XNOR gate. The switch k1 should be a unidirectional switch to ensure the unidirectionality of the current path. The amplifier AMP1 is preferably an LM741, but other amplifiers with higher gain and a wider output voltage range can also be selected.

[0017] The threshold generation circuit includes a power supply CV (preferably a constant voltage source of model E3634A), a switch k11, a switch k12, a resistor R11, an adjustable resistor R12, a resistor R13, a resistor R14, a diode D11, a switch Q11, and a capacitor C11. The power supply CV is connected to one end of the switch k11 and one end of the switch k12. The other end of the switch k12 is connected to one end of the capacitor C11, serving as the output end of the threshold generation circuit. The other end of the capacitor C11 is grounded. The other end of the switch k11 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to one end of the adjustable resistor R12, one end of the resistor R14, one end of the switch Q11, and one end of the capacitor C11. The other end of the adjustable resistor R12 is grounded via the resistor R13. The other end of the resistor R14 is connected to the cathode of the diode D11 and the control end of the switch Q11. The anode of the diode D11 and the other end of the switch Q11 are grounded. The diode D11 is a voltage-stabilizing diode. The above-mentioned adjustable resistor can be a precision potentiometer, or a parallel resistor switching network, or a MOS analog resistor network, which is not limited here.

[0018] The following is attached with the instruction manual Figure 3 and attached Figure 4 The principle of overcharge and over-discharge protection of the buoy battery compartment of the present invention is briefly introduced: For the charging protection of the buoy battery compartment, it is first necessary to disconnect the discharge protection switch P4 and turn on the charging protection switch P2, so that the solar panel 8 can charge the lithium battery P3 through the power regulation circuit P1. At the same time, the switch k1 is controlled to be disconnected, the switch k12 is controlled to be disconnected, and the switch k11 is controlled to be turned on. At this time, the threshold generation circuit generates a first threshold value (that is, a charging threshold value) related to the constant voltage power supply CV and the threshold value of the Zener diode D11 through the resistor R11, the adjustable resistor R12, the resistor R13, the resistor R14, the Zener diode D11, the switch Q11 and the capacitor C11, and connects the first threshold value to the control signal generation circuit through the output terminal VCC of the threshold generation circuit. Since the switch k1 is disconnected, when the detected battery voltage VB is greater than the first threshold value (that is, greater than the charging threshold value, it can be considered that overcharging occurs at this time), , there is a current path of battery voltage VB-diode D1-resistor R1-VCC, so that a positive voltage at the top and a negative voltage at the bottom can be generated on the resistor R1, the amplifier AMP1 outputs a high level, one input end of the logic gate L1 is a high level, and the other input end of the logic gate L1 is a low level (the other input end of the logic gate L1 is the control signal of the switch k1, and the switch k1 is disconnected at this time, so it is a low level). Therefore, the logic gate L1 outputs a low level, thereby controlling the charging protection switch P2 to be disconnected through the first control end P61 to achieve overcharge protection; when the detected battery voltage VB is lower than the first threshold, one input end of the logic gate L1 is a low level, and the other input end of the logic gate L1 is a low level. At this time, the logic gate L1 outputs a high level, the charging protection switch P2 remains on, and the lithium battery P3 also maintains a charging state.

[0019] For the discharge protection of the buoy battery compartment, it is first necessary to disconnect the charging protection switch P2 and turn on the discharge protection switch P4, so that the lithium battery P3 can power the load P5. At the same time, the switch k1 is controlled to be turned on, the switch k12 is turned on, and the switch k11 is turned off. At this time, the threshold generation circuit directly uses the constant voltage power supply CV as the second threshold (that is, the discharge threshold), and connects the second threshold to the control signal generation circuit through the output terminal VCC of the threshold generation circuit. Since the switch k1 is turned on, when the detected battery voltage VB is less than the second threshold (that is, less than the discharge threshold and over-discharge occurs), there is a current path of VCC-resistor R1-switch k1-battery voltage VB, so A voltage with a positive bottom and a negative top can be generated on the resistor R1. The amplifier AMP1 outputs a low level, one input terminal of the logic gate L1 is at a low level, and the other input terminal of the logic gate L1 is at a high level (the control signal of the switch k1, at this time the switch k1 is turned on and therefore at a high level). Therefore, the logic gate L1 outputs a low level, thereby controlling the discharge protection switch P4 to be disconnected through the second control terminal P62 to achieve over-discharge protection. When the detected battery voltage VB is greater than the second threshold, the amplifier AMP1 outputs a high level, one input terminal of the logic gate L1 is at a high level, and at this time the logic gate L1 outputs a high level, the discharge protection switch P4 remains on, and the lithium battery P4 also maintains a discharge state.

[0020] It should be noted that the threshold generation circuit provided in the present invention includes an adjustable resistor R12, which can conveniently change the threshold output by the threshold generation circuit by adjusting the resistance of the adjustable resistor R12, thereby meeting the overcharge or over-discharge protection requirements for lithium batteries of different types and lifespans, thereby improving the versatility of the overcharge and over-discharge protection circuit. The present invention utilizes the same control signal generation circuit to generate both charge protection and discharge protection control signals, and utilizes the same threshold generation circuit to generate both the first threshold and the second threshold, thereby miniaturizing the device and simplifying the system structure.

[0021] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and do not impose any form of limitation on the implementation methods of the technology of the present invention. Any person skilled in the art may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0022] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A buoy battery compartment overcharge and overdischarge protection circuit, characterized in that: The offshore buoy system comprises a solar panel, a power regulating circuit, a charging protection switch, a lithium battery, a discharge protection switch, a load and a control circuit, wherein the solar panel, the power regulating circuit, the charging protection switch, the lithium battery, the discharge protection switch and the load are connected in sequence; The control circuit is used to detect the voltage of the lithium battery and generate a first control signal when the voltage of the lithium battery is greater than a first threshold value, and control the charging protection switch to be disconnected through the first control end; when the voltage of the lithium battery is less than a second threshold value, a second control signal is generated, and control the discharge protection switch to be disconnected through the second control end, thereby realizing overcharge and over-discharge protection of the buoy battery compartment; the first threshold value is greater than the second threshold value.

2. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 1, characterized in that: The control circuit includes a control signal generating circuit and a threshold generating circuit. The threshold generating circuit generates the first threshold and the second threshold. The control signal generating circuit is connected to the output end of the threshold generating circuit and generates a first control signal or a second control signal according to the first threshold or the second threshold.

3. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 2, characterized in that: The control signal generating circuit includes a detected battery voltage VB, a diode D1, a switch k1, a resistor R1, an amplifier AMP1 and a logic gate L1. The detected battery voltage VB is connected to the anode of the diode D1 and one end of the switch k1, the cathode of the diode D1 and the other end of the switch k1 are connected to one end of the resistor R1, the other end of the resistor R1 is connected to the output end of the threshold generating circuit, the positive input end of the amplifier AMP1 is connected to one end of the resistor R1, the negative input end of the amplifier AMP1 is connected to the other end of the resistor R1, the output end of the amplifier AMP1 is connected to one input end of the logic gate L1, and the other input end of the logic gate L1 inputs the control signal of the switch k1.

4. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 3, characterized in that: The logic gate L1 is an XNOR gate.

5. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 2, characterized in that: The threshold generation circuit includes a power supply CV, a switch k11, a switch k12, a resistor R11, an adjustable resistor R12, a resistor R13, a resistor R14, a diode D11, a switch Q11, and a capacitor C11. The power supply CV is connected to one end of the switch k11 and one end of the switch k12. The other end of the switch k12 is connected to one end of the capacitor C11, serving as the output end of the threshold generation circuit. The other end of the capacitor C11 is grounded. The other end of the switch k11 is connected to one end of the resistor R11. The other end of the resistor R11 is connected to one end of the adjustable resistor R12, one end of the resistor R14, one end of the switch Q11, and one end of the capacitor C11. The other end of the adjustable resistor R12 is grounded via the resistor R13. The other end of the resistor R14 is connected to the cathode of the diode D11 and the control end of the switch Q11. The anode of the diode D11 and the other end of the switch Q11 are grounded.

6. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 5, characterized in that: The diode D11 is a voltage stabilizing diode.

7. A buoy battery compartment overcharge and overdischarge protection circuit according to claim 1, characterized in that: The offshore buoy system includes an integrated weather station, an antenna, an atmospheric radiometer, a battery compartment, a temperature probe, a single-point current meter, a navigation light, a solar panel, a wave meter, a float, and a nuclear radiometer.

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