Lithium battery protection board power supply system, lithium battery protection board and lithium battery

Abstract

The invention relates to a lithium battery protection board power supply system, a lithium battery protection board and a lithium battery, the lithium battery protection board power supply system comprises a first power supply module, a second power supply module and a first voltage stabilizing element, the input end of the first power supply module and the input end of the second power supply module are both electrically connected with the positive electrode of a battery pack; the output end of the first power supply module and the output end of the second power supply module are connected with the input end of the first voltage stabilizing element. The output end of the first voltage stabilizing element is used for being electrically connected with the micro-control unit and the first logic circuit. The output power of the first power supply module is the same as the sleep power of the micro-control unit, the output power of the second power supply module is larger than the output power of the first power supply module, opening and closing of the second power supply module are controlled by the micro-control unit, and the output end of the second power supply module is further used for being electrically connected with a second logic circuit. The first power supply module and the second power supply module are arranged, so that the electric quantity consumed by the protection plate is small when the lithium battery stands, and the lithium battery can stand for a long time at low power.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and particularly to a power supply system for a lithium battery protection board, a lithium battery protection board, and a lithium battery. Background Art

[0002] Lithium batteries usually need to be equipped with a protection board to ensure that they operate within a specific voltage, current, and temperature range. Currently, lithium battery protection boards are divided into two categories: pure hardware protection boards and intelligent software protection boards. Pure hardware protection boards have the characteristics of low cost and high production efficiency in the lithium battery protection board market, so they were widely used in early lithium battery protection. Due to reasons such as fixed protection strategies and low protection levels, pure hardware protection boards are gradually being replaced by intelligent software protection boards. Intelligent software protection boards mainly consist of complex modules such as a power supply system, a microcontroller unit, a communication circuit, and a logic circuit. The intelligent software protection board is electrically connected to the positive electrode of the lithium battery, and the power supply system converts the voltage of the lithium battery into a lower voltage to meet the voltage requirements for the operation of the microcontroller unit, communication circuit, logic circuit, etc.

[0003] The power supply system of the intelligent software protection board cannot be turned off. Once the power supply system is turned off, it will be difficult for the microcontroller unit to start up. And the existing intelligent software protection boards have high power consumption during operation. This means that even if the lithium battery is not discharging externally and is in a static state, a large amount of electrical energy will be consumed by the protection board in a short period of time. If the lithium battery is in a static state for a long time, it will experience power loss, resulting in the limitation of the static time of the lithium battery and restricting the use of the lithium battery. Summary of the Invention

[0004] Based on this, it is necessary to provide a power supply system for a lithium battery protection board, a lithium battery protection board, and a lithium battery to address the problem of the short static time of lithium batteries in the prior art.

[0005] To achieve the above object, in a first aspect, the present application provides a power supply system for a lithium battery protection board, including a first power supply module, a second power supply module, and a first voltage stabilizing element. The input ends of the first power supply module and the second power supply module are both electrically connected to the positive electrode of the battery pack. The output ends of the first power supply module and the second power supply module are both connected to the input end of the first voltage stabilizing element. The output end of the first voltage stabilizing element is used to be electrically connected to a micro control unit and a first logic circuit. The output end of the second power supply module is also used to be electrically connected to a second logic circuit; the output power of the second power supply module is greater than the output power of the first power supply module, and the on and off of the second power supply module are controlled by the micro control unit; when the second power supply module is turned off, the first power supply module supplies power to the micro control unit and the first logic circuit, so that the protection board enters the sleep state; when the second power supply module is turned on, the second power supply module and the first power supply module supply power to the micro control unit and the first logic circuit, and the second power supply module also supplies power to the second logic circuit, so that the protection board works normally.

[0006] In the above lithium battery protection board power supply system, the first power supply module remains in the on state, and the protection board enters the normal working state or the sleep state by controlling the switch of the second power supply module through the micro control unit to adapt to the state of the lithium battery. Specifically, during the normal operation of the lithium battery, the second power supply module is turned on so that the protection board works normally. At this time, the second power supply module and the first power supply module supply power to the micro control unit together, and the second logic circuit with a higher power consumption electrically connected to the second power supply module works normally; when the lithium battery is in a static state, the second power supply module is turned off so that the protection board enters the sleep state. At this time, only the first power supply module provides electrical energy with a smaller power to the micro control unit, and the second logic circuit with a higher power consumption electrically connected to the second power supply module pauses working. The power consumption of the micro control unit and the protection board is correspondingly smaller than that of the micro control unit and the protection board during the normal operation of the lithium battery. It can be seen that the setting of the first power supply module and the second power supply module realizes the controllable power consumption of the protection board, not only ensures that the protection board and the lithium battery can work normally, but also makes the power consumed by the protection board when the lithium battery is static smaller, enables the lithium battery to be static at a low power for a long time without discharging, and effectively extends the static time of the lithium battery. In addition, the power consumption of the micro control unit during the normal operation of the lithium battery is greater than that of the micro control unit when the lithium battery is static. By connecting the output ends of the first power supply module and the second power supply module to the input end of the first voltage stabilizing element, and electrically connecting the output end of the first voltage stabilizing element to the micro control unit, the first power supply module and the second power supply module supply power to the micro control unit together when the lithium battery works normally, preventing the first power supply module from overheating and failing during the normal operation of the lithium battery.

[0007] In some embodiments, the first power supply module includes a first current limiting element and a voltage regulating unit. The positive electrode of the battery pack, the first current limiting element, the voltage regulating unit, and the first voltage stabilizing element are connected in series in sequence. The voltage regulating unit is configured to control the voltage value output to the first voltage stabilizing element.

[0008] In some embodiments, the voltage regulating unit includes a power device, a second voltage stabilizing element, and a first voltage dividing element. The input electrode of the power device is electrically connected to the first current limiting element. The output electrode of the power device is electrically connected to the input end of the first voltage stabilizing element. The control electrode of the power device is electrically connected to the negative electrode of the second voltage stabilizing element, and the positive electrode of the second voltage stabilizing element is grounded. The first current limiting element, the first voltage dividing element, and the negative electrode of the second voltage stabilizing element are connected in series in sequence.

[0009] In some embodiments, the second power supply module includes a second current limiting element, a first switching unit, and a DC conversion unit. The positive electrode of the battery pack, the second current limiting element, the first switching unit, the DC conversion unit, and the first voltage stabilizing element are connected in series in sequence. The output end of the DC conversion unit is further configured to be electrically connected to a second logic circuit. The first switching unit is controlled by the micro control unit to control the switching of the second power supply module.

[0010] In some embodiments, the first switching unit includes a first switching element, a second switching element, a second voltage dividing element, and a third voltage dividing element. The input electrode of the first switching element is electrically connected to the second current limiting element. The output electrode of the first switching element is electrically connected to the input end of the DC conversion unit. The control electrode of the second switching element is configured to be electrically connected to the micro control unit. The output electrode of the second switching element is grounded. The input electrode of the second switching element, the third voltage dividing element, and the control electrode of the first switching element are connected in series in sequence. The second current limiting element, the second voltage dividing element, and the third voltage dividing element are connected in series in sequence.

[0011] In some embodiments, the second power supply module further includes an anti reverse connection diode. The positive electrode of the anti reverse connection diode is electrically connected to the output end of the DC conversion unit. The negative electrode of the anti reverse connection diode is electrically connected to the input end of the first voltage stabilizing element.

[0012] In some embodiments, the lithium battery protection board power supply system further includes a signal switching module. The input end of the signal switching module is electrically connected to the output end of the first voltage stabilizing element. The signal switching module is configured to be electrically connected to a signal circuit and the micro control unit to control the switching of the signal circuit.

[0013] In some embodiments, the signal switch module includes a third switching element, a fourth voltage-dividing element, and a fifth voltage-dividing element. The input electrode of the third switching element is electrically connected to the output terminal of the first voltage-regulating element. The output electrode of the third switching element is for electrically connecting to the signal circuit. The control electrode of the third switching element is electrically connected to the fifth voltage-dividing element. The output terminal of the first voltage-regulating element, the fourth voltage-dividing element, and the fifth voltage-dividing element are connected in series in sequence. The fifth voltage-dividing element is further for electrically connecting to the micro-control unit.

[0014] In some embodiments, the lithium battery protection board power supply system further includes a communication switch module. The input end of the communication switch module is electrically connected to the output terminal of the second power supply module. The communication switch module is for electrically connecting to a communication circuit and the micro-control unit to control the switch of the communication circuit.

[0015] In some embodiments, the communication switch module includes a second switching unit, a third voltage-regulating element, and an isolation unit. The output terminal of the second power supply module, the second switching unit, the third voltage-regulating element, and the isolation unit are connected in series in sequence. The isolation unit is further for electrically connecting to the communication circuit. The second switching unit is further for electrically connecting to the micro-control unit. The isolation unit is for isolating the communication signal output by the third voltage-regulating element.

[0016] In some embodiments, the second switching unit includes a fourth switching element, a fifth switching element, a sixth voltage-dividing element, and a seventh voltage-dividing element. The input electrode of the fourth switching element is electrically connected to the output terminal of the second power supply module. The output electrode of the fourth switching element is electrically connected to the input end of the third voltage-regulating element. The control electrode of the fifth switching element is for electrically connecting to the micro-control unit. The output electrode of the fifth switching element is grounded. The input electrode of the fifth switching element, the seventh voltage-dividing element, and the control electrode of the fourth switching element are connected in series in sequence. The output terminal of the second power supply module, the sixth voltage-dividing element, and the seventh voltage-dividing element are connected in series in sequence.

[0017] In some embodiments, the isolation unit includes a conversion unit and a transformer. The conversion unit is for converting the direct current output by the third voltage-regulating element into alternating current and transmitting it to the primary coil of the transformer. The secondary coil of the transformer is for electrically connecting to the communication circuit. Both the primary coil and the secondary coil are grounded and the grounding grids are different.

[0018] In a second aspect, the present application provides a lithium battery protection board, including the lithium battery protection board power supply system provided in the first aspect.

[0019] In a third aspect, the present application provides a lithium battery, including the lithium battery protection board provided in the second aspect. Brief Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a structural block diagram of a power supply system for a lithium battery protection board provided by the present application;

[0022] Figure 2 It is a schematic structural diagram of a first power supply module provided in an embodiment;

[0023] Figure 3 It is a schematic structural diagram of a second power supply module provided in an embodiment;

[0024] Figure 4 It is a schematic structural diagram of a signal switch module provided in an embodiment;

[0025] Figure 5 It is a structural block diagram of a communication switch module provided in an embodiment;

[0026] Figure 6 It is a schematic structural diagram of a second switch unit provided in an embodiment;

[0027] Figure 7 It is a schematic structural diagram of an isolation unit provided in an embodiment;

[0028] Figure 8 It is a schematic structural diagram of a power supply system for a lithium battery protection board provided in an embodiment;

[0029] Description of the Reference Numerals:

[0030] 1 - First power supply module; 11 - Micro - control unit; 12 - First logic circuit; 13 - Voltage adjustment unit; 2 - Second power supply module; 21 - Second logic circuit; 22 - First switch unit; 3 - Battery pack; 4 - Signal switch module; 41 - Signal circuit; 5 - Communication switch module; 51 - Communication circuit; 52 - Second switch unit; 53 - Isolation unit. Detailed Description of the Embodiments

[0031] To facilitate the understanding of the present application, the following will describe the present application more comprehensively with reference to the relevant drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0033] In a first aspect, referring to Figure 1 , this application provides a power supply system for a lithium battery protection board, including a first power supply module 1, a second power supply module 2, and a first voltage stabilizing element L1. The input ends of the first power supply module 1 and the second power supply module 2 are electrically connected to the positive electrode of the battery pack 3. The output ends of the first power supply module 1 and the second power supply module 2 are both connected to the input end of the first voltage stabilizing element L1. The output end of the first voltage stabilizing element L1 is used to be electrically connected to the micro control unit 11 and the first logic circuit 12. The output end of the second power supply module 2 is also used to be electrically connected to the second logic circuit 21. The output power of the second power supply module 2 is greater than the output power of the first power supply module 1, and the on and off of the second power supply module 2 are controlled by the micro control unit 11. When the second power supply module 2 is turned off, the first power supply module 1 supplies power to the micro control unit 11 and the first logic circuit 12 to make the protection board enter the sleep state. When the second power supply module 2 is turned on, the second power supply module 2 and the first power supply module 1 supply power to the micro control unit 11 and the first logic circuit 12, and the second power supply module 2 also supplies power to the second logic circuit 21 to make the protection board work normally.

[0034] In the above lithium battery protection board power supply system, the first power supply module 1 remains in the on state, and the micro control unit 11 controls the switch of the second power supply module 2 to enable the protection board to enter the normal working state or the sleep state, so as to adapt to the state of the lithium battery. Specifically, during the normal operation of the lithium battery, the second power supply module 2 is turned on to enable the protection board to work normally. At this time, the second power supply module 2 and the first power supply module 1 supply power to the micro control unit 11 together, and the second logic circuit 21 with relatively high power consumption electrically connected to the second power supply module 2 works normally; when the lithium battery is in a static state, the second power supply module 2 is turned off to enable the protection board to enter the sleep state. At this time, only the first power supply module 1 provides electrical energy with a relatively small power for the micro control unit 11, and the second logic circuit 21 with relatively high power consumption electrically connected to the second power supply module 2 pauses working. The power consumption of both the micro control unit 11 and the protection board is correspondingly less than the power consumption of the micro control unit 11 and the protection board when the lithium battery is working normally. Thus, it can be seen that the setting of the first power supply module 1 and the second power supply module 2 realizes controllable power consumption of the protection board, not only ensures that the protection board and the lithium battery can work normally, but also makes the power consumption of the protection board when the lithium battery is static relatively small, enabling the lithium battery to be static at a low power for a long time without discharging, effectively extending the static time of the lithium battery. In other words, when the protection board enters the sleep state, it enters the state to be activated. The dual power supply modules provide power support for the protection board to enter the sleep state. When the protection board is in the sleep state, the second power supply module 2 is turned off, and only the first power supply module 1 needs to maintain the tiny current required for the micro control unit 11 to wait for activation, and the current is not greater than 30 μA.

[0035] Meanwhile, when the lithium battery is working normally, the power consumption of the micro control unit 11 is greater than that of the micro control unit 11 when the lithium battery is static. At this time, the first power supply module 1 is not sufficient to provide all the electrical energy required by the micro control unit 11. By connecting the output terminals of both the first power supply module 1 and the second power supply module 2 to the input terminal of the first voltage stabilizing element, and electrically connecting the output terminal of the first voltage stabilizing element to the micro control unit 11, when the lithium battery is working normally, the first power supply module 1 and the second power supply module 2 supply power to the micro control unit 11 together, preventing the first power supply module 1 from overheating and failing during the normal operation of the lithium battery.

[0036] In addition, when the protection board is in the sleep state, the first power supply module 1 only needs to provide the tiny current required for the protection board to sleep. The power consumption of the first power supply module 1 is extremely low, which makes the current flowing through each electronic component in the first power supply module 1 extremely small. On the one hand, this makes the heat generation of each electronic component of the first power supply module 1 extremely small, and the first power supply module 1 can work in the best state for a long time, which is beneficial to improving the safety of the entire power supply system; on the other hand, this makes the selection, design and debugging process of each electronic component in the first power supply module 1 simpler, facilitating mass use; on the other hand, this also makes each electronic component in the first power supply module 1 have a smaller package volume, so that the first power supply module 1 has a smaller volume, facilitating the installation of the first power supply module 1.

[0037] The first logic circuit 12 includes an activation circuit for transmitting an activation signal. The activation circuit is used to restore the protection board from the sleep state to the normal working state. The first activation circuit belongs to a non-sleepable circuit; the second logic circuit 21 contains electronic components that can pause working when the lithium battery is stationary, and some of the electronic components have a relatively large power consumption, much larger than the power consumption when the microcontroller unit 11 is in the sleep state. Therefore, the output power of the second power supply module 2 is much larger than the output power of the first power supply module 1. Both the first power supply module 1 and the second power supply module 2 are input from the highest section B+ of the battery positive electrode.

[0038] Specifically, the output power of the first power supply module 1 is slightly larger than the sum of the powers required by the microcontroller unit 11 and the first logic circuit 12 in the sleep state of the protection board; the first voltage stabilizing element L1 includes but is not limited to a low-dropout regulator (LDO), also known as a low-dropout linear regulator; the microcontroller unit 11 includes a single-chip microcomputer.

[0039] In some embodiments, refer to Figure 2 Figure, the first power supply module 1 includes a first current limiting element R1 and a voltage adjustment unit 13. The positive electrode B+ of the battery pack 3, the first current limiting element R1, the voltage adjustment unit 13 and the first voltage stabilizing element L1 are connected in series in sequence. The voltage adjustment unit 13 is used to control the voltage value output to the first voltage stabilizing element L1, and the first voltage stabilizing element L1 controls the voltage value output to the microcontroller unit 11 and the first logic circuit 12. The voltage output from the highest section B+ of the battery positive electrode passes through the first current limiting element R1 and then is output to the voltage adjustment unit 13. The voltage adjustment unit 13 outputs voltage V1 to the input end of the first voltage stabilizing element L1, and outputs voltage V2 from the output end of the first voltage stabilizing element L1 to the microcontroller unit 11 and the first logic circuit 12.

[0040] Specifically, the first current limiting element R1 includes but is not limited to a resistor, and its resistance value can be selected according to needs.

[0041] In some embodiments, continue to refer to Figure 2, the voltage adjustment unit 13 includes a power device Q1, a second voltage stabilizing element D1, and a first voltage dividing element R2; the input electrode of the power device Q1 is electrically connected to the first current limiting element R1, the output electrode of the power device Q1 is electrically connected to the input end of the first voltage stabilizing element L1, the control electrode of the power device Q1 is electrically connected to the negative electrode of the second voltage stabilizing element D1, and the positive electrode of the second voltage stabilizing element D1 is grounded; the first current limiting element R1, the first voltage dividing element R2, and the negative electrode of the second voltage stabilizing element D1 are connected in series in sequence, and the power device Q1 outputs a voltage V1. The first voltage dividing element R2 and the second voltage stabilizing element D1 form a voltage dividing circuit. The first voltage dividing element R2 shares a part of the voltage and current for the second voltage stabilizing element D1 to prevent the second voltage stabilizing element D1 from being reversely broken down; the second voltage stabilizing element D1 plays a voltage stabilizing role. The power device Q1 operates in the linear region. The control electrode voltage of the power device Q1 is equal to the voltage of the second voltage stabilizing element. The output voltage V1 of the power device Q1 is slightly lower than the voltage of the second voltage stabilizing element D1. Therefore, adjusting the voltage stabilizing value of the second voltage stabilizing element D1 can adjust the output voltage V1 of the power device Q1; the power device Q1 and the first current limiting element R1 jointly bear the voltage drop from the highest section B+ of the battery positive electrode to V1.

[0042] Specifically, the power device Q1 includes, but is not limited to, a Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET), an Insulate-Gate Bipolar Transistor (IGBT), a triode, etc. The input electrode of the MOSFET is the drain D, the output electrode is the source S, and the control electrode is the gate G; the input electrode of the IGBT is the collector, the output electrode is the emitter, and the control electrode is the gate; the input electrode of the triode is the collector, the output electrode is the emitter, and the control electrode is the base. The second voltage stabilizing element D1 includes, but is not limited to, a zener diode. The first voltage dividing element R2 includes, but is not limited to, a resistor, and its resistance value can be selected according to needs.

[0043] In some embodiments, refer to Figure 3, the second power supply module 2 includes a second current limiting element R5, a first switching unit 22, and a DC conversion unit U1. The positive electrode of the battery pack 3, the second current limiting element R5, the first switching unit 22, the DC conversion unit U1, and the first voltage stabilizing element L1 are connected in series in sequence. The output terminal of the DC conversion unit U1 is also used for electrical connection to the second logic circuit 21. The first switching unit 22 is controlled by the micro control unit 11 to control the switching of the second power supply module 2. In other words, the micro control unit 11 controls the switching of the second power supply module 2 by controlling the switching of the first switching unit 22, so as to control whether the second power supply module 2 supplies power to the second logic circuit 21 and the first voltage stabilizing element L1, and further control whether the protection board works normally or is in a sleep state. When the first switching unit 22 is turned off, the entire second power supply module 2 is in the off state, the second power supply module 2 does not supply power to the second logic circuit 21 and the first voltage stabilizing element L1, and the protection board is in a sleep state; when the first switching unit 22 is turned on, the voltage output from the highest section B+ of the battery positive electrode is output to the first switching unit 22 after passing through the second current limiting element R5. The first switching unit 22 outputs a voltage to the DC conversion unit U1, and the DC conversion unit U1 outputs a voltage V3 to the second logic circuit 21 and the first voltage stabilizing element L1 to supply power to the second logic circuit 21 and the micro control unit 11. The DC conversion unit U1 can adjust its output voltage V3 as needed.

[0044] Specifically, the second current limiting element R5 includes but is not limited to a resistor, and its resistance value can be selected as needed; the DC conversion unit U1 is a DC / DC converter.

[0045] In some embodiments, continue to refer to Figure 3 , the first switching unit 22 includes a first switching element Q3, a second switching element T1, a second voltage dividing element R6, and a third voltage dividing element R7; the input electrode of the first switching element Q3 is electrically connected to the second current limiting element R5, and the output electrode of the first switching element Q3 is electrically connected to the input terminal of the DC conversion unit U1; the control electrode of the second switching element T1 is used for electrical connection to the micro control unit 11, the output electrode of the second switching element T1 is grounded, the input electrode of the second switching element T1, the third voltage dividing element R7, and the control electrode of the first switching element Q3 are connected in series in sequence, and the second current limiting element R5, the second voltage dividing element R6, and the third voltage dividing element R7 are connected in series in sequence.

[0046] Specifically, the control electrode of the second switching element T1 is electrically connected to the signal control port MCU-EN of the microcontroller unit 11. When the protection board is in the sleep state, the signal control port MCU-EN is at a low level, the second switching element T1 is turned off, and the first switching element Q3 has no bias voltage and is turned off, and the entire second power supply module 2 is in the off state. When the microcontroller unit 11 is activated, the protection board works normally, the signal control port MCU-EN is at a high level, the second switching element T1 conducts, and the second voltage dividing element R6 and the third voltage dividing element R7 divide the voltage to provide a bias voltage for the first switching element Q3, so that the first switching element Q3 conducts.

[0047] Specifically, the first switching element Q3 and the second switching element T1 independently include but are not limited to Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET), Insulate-Gate Bipolar Transistor (IGBT), triode, etc.; the input electrode of the MOSFET is the drain D, the output electrode is the source S, and the control electrode is the gate G; the input electrode of the IGBT is the collector, the output electrode is the emitter, and the control electrode is the gate; the input electrode of the triode is the collector, the output electrode is the emitter, and the control electrode is the base; preferably, the second switching element T1 is an NPN triode. The second voltage dividing element R6 and the third voltage dividing element R7 independently include but are not limited to resistors, and their resistance values can be selected according to needs.

[0048] In some embodiments, continue to refer to Figure 3 , the second power supply module 2 may further include an anti-reverse connection diode D2. The positive electrode of the anti-reverse connection diode D2 is electrically connected to the output terminal of the DC conversion unit U1, and the negative electrode of the anti-reverse connection diode D2 is electrically connected to the input terminal of the first voltage stabilizing element L1. The DC conversion unit U1 outputs a voltage V3 to the anti-reverse connection diode D2, and the anti-reverse connection diode D2 outputs a voltage V1 to the input terminal of the first voltage stabilizing element L1, so as to supply power to the microcontroller unit 11 and the first logic circuit 12. The anti-reverse connection diode D2 is used to prevent the voltage V1 output by the first power supply module 1 from being back-fed to the second logic circuit 21, thereby avoiding the failure of the first power supply module 1 due to excessive temperature rise caused by excessive power of the first power supply module 1. And since the first voltage stabilizing element L1 is located at the subsequent stage of the first power supply module 1, when the current from the second power supply module 2 enters the first voltage stabilizing element L1, it will not enter the first power supply module 1 and cause its temperature to rise.

[0049] In some embodiments, continue to refer to Figure 1, the power supply system of the lithium battery protection board further includes a signal switch module 4. The input end of the signal switch module 4 is electrically connected to the output end of the first voltage stabilizing element L1. The signal switch module 4 is used to be electrically connected to the signal circuit 41 and the micro control unit 11 to control the switch of the signal circuit 41. In other words, the micro control unit 11 controls the switch of the signal switch module 4 to control whether the first power supply module 1 supplies power to the signal circuit 41. To control the power consumption of the protection board, the signal circuit 41 in the protection board does not need to work continuously. When the signal circuit 41 does not work, the micro control unit 11 controls the signal switch module 4 to turn off, and the first power supply module 1 stops supplying power to the signal circuit 41. When the signal circuit 41 needs to work, the micro control unit 11 controls the signal switch module 4 to turn on, and the current output by the first power supply module 1 enters the signal circuit 41 after passing through the first voltage stabilizing element L1 and the signal switch module 4 to supply power to the signal circuit 41.

[0050] In some embodiments, referring to Figure 4 , the signal switch module 4 includes a third switching element Q2, a fourth voltage dividing element R3, and a fifth voltage dividing element R4. The input electrode of the third switching element Q2 is electrically connected to the output end of the first voltage stabilizing element L1. The output electrode of the third switching element Q2 is used to be electrically connected to the signal circuit 41. The control electrode of the third switching element Q2 is electrically connected to the fifth voltage dividing element R4. The output end of the first voltage stabilizing element L1, the fourth voltage dividing element R3, and the fifth voltage dividing element R4 are connected in series in sequence. The fifth voltage dividing element R4 is also used to be electrically connected to the micro control unit 11.

[0051] Specifically, the control electrode of the third switching element Q2 is electrically connected to the signal control port MCU-V4 of the micro control unit 11 through the fifth voltage dividing element R4. When the signal circuit 41 does not work, the signal control port MCU-V4 is in a high impedance state, the third switching element Q2 is turned off, the signal switch module 4 is turned off, and no current enters the signal circuit 41. When the signal circuit 41 needs to work, the micro control unit 11 controls the signal control port MCU-V4 to output a low level, the third switching element Q2 conducts, the fourth voltage dividing element R3 and the fifth voltage dividing element R4 divide the voltage, and the output electrode of the third switching element Q2 supplies power to the signal circuit 41.

[0052] Specifically, the third switching element Q2 includes, but is not limited to, a Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET), an Insulate-Gate Bipolar Transistor (IGBT), a triode, etc.; the input electrode of the MOSFET is the drain D, the output electrode is the source S, and the control electrode is the gate G; the input electrode of the IGBT is the collector, the output electrode is the emitter, and the control electrode is the gate; the input electrode of the triode is the collector, the output electrode is the emitter, and the control electrode is the base. The fourth voltage-dividing element R3 and the fifth voltage-dividing element R4 each independently include, but are not limited to, a resistor, and their resistance values can be selected according to needs.

[0053] In some embodiments, referring further to Figure 1 , the power supply system of the lithium battery protection board further includes a communication switch module 5. The input end of the communication switch module 5 is electrically connected to the output end of the second power supply module 2. The communication switch module 5 is used to be electrically connected to the communication circuit 51 and the micro-control unit 11 to control the switch of the communication circuit 51. In other words, the micro-control unit 11 controls whether the second power supply module 2 supplies power to the communication circuit 51 by controlling the switch of the communication switch module 5. When the protection board communicates, the power consumption is relatively large. In order to control the power consumption of the protection board, when communication is not required, the micro-control unit 11 controls the communication switch module 5 to turn off, and the second power supply module 2 stops supplying power to the communication circuit 51; when communication is required, the micro-control unit 11 controls the communication switch module 5 to turn on, and the current output by the second power supply module 2 enters the communication circuit 51 through the communication switch module 5 to supply power to the communication circuit 51.

[0054] In some embodiments, referring to Figure 5 , the communication switch module 5 includes a second switching unit 52, a third voltage regulator element L2, and an isolation unit 53. The output end of the second power supply module 2, the second switching unit 52, the third voltage regulator element L2, and the isolation unit 53 are connected in series in sequence. The isolation unit 53 is also used to be electrically connected to the communication circuit 51, and the second switching unit 52 is also used to be electrically connected to the micro-control unit 11. The micro-control unit 11 controls the switch of the communication switch module 5 by controlling the switch of the second switching unit 52, so as to control whether the second power supply module 2 supplies power to the communication circuit 51. The communication signal is a high-frequency signal and is extremely vulnerable to interference, resulting in communication failure. The isolation unit 53 isolates the communication signal output by the third voltage regulator element L2 to improve the communication success rate.

[0055] Specifically, the third voltage regulator element L2 includes, but is not limited to, a Low-dropout regulator (LDO), also known as a low-dropout linear regulator.

[0056] It should be noted that the output terminal of the third switching unit 52 can also be electrically connected to other logic circuits adapted to its output voltage value, the output terminal of the third voltage stabilizing element L2 can also be electrically connected to other logic circuits adapted to its output voltage value, and the output terminal of the isolation unit 53 can also be electrically connected to other logic circuits that need to isolate the voltage and are adapted to its output voltage value.

[0057] In some embodiments, referring to Figure 6 , the second switching unit 52 includes a fourth switching element Q4, a fifth switching element Q5, a sixth voltage dividing element R8, and a seventh voltage dividing element R9; the input electrode of the fourth switching element Q4 is electrically connected to the output terminal of the second power supply module 2, and the output electrode of the fourth switching element Q4 is electrically connected to the input terminal of the third voltage stabilizing element L2; the control electrode of the fifth switching element Q5 is used to be electrically connected to the micro control unit 11, the output electrode of the fifth switching element Q5 is grounded, the input electrode of the fifth switching element Q5, the seventh voltage dividing element R9, and the control electrode of the fourth switching element Q4 are connected in series in sequence, and the output terminal of the second power supply module 2, the sixth voltage dividing element R8, and the seventh voltage dividing element R9 are connected in series in sequence.

[0058] Specifically, the control electrode of the fifth switching element Q5 is electrically connected to the signal control port MCU-V3 of the micro control unit 11. When the protection board does not need to communicate, the signal control port MCU-V3 is at a low level, the fifth switching element Q5 is turned off, so that the fourth switching element Q4 has no bias voltage and is turned off, and the entire communication switching module 5 is in the off state and does not supply power to the communication circuit 51. When the protection board needs to communicate, the signal control port MCU-V3 is at a high level, the fifth switching element Q5 is turned on, the sixth voltage dividing element R8 and the seventh voltage dividing element R9 divide the voltage, the fourth switching element Q4 has a bias voltage and is turned on, and outputs a voltage V3-1 to the third voltage stabilizing element L2 to supply power to the communication circuit 51.

[0059] Specifically, the fourth switching element Q4 and the fifth switching element Q5 independently include, but are not limited to, Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET), Insulate-Gate Bipolar Transistor (IGBT), triode, etc.; the input electrode of the MOSFET is the drain D, the output electrode is the source S, and the control electrode is the gate G; the input electrode of the IGBT is the collector, the output electrode is the emitter, and the control electrode is the gate; the input electrode of the triode is the collector, the output electrode is the emitter, and the control electrode is the base; preferably, the fifth switching element Q5 is a MOSFET. The sixth voltage-dividing element R8 and the seventh voltage-dividing element R9 independently include, but are not limited to, resistors, and their resistance values can be selected as needed.

[0060] In some embodiments, referring to Figure 7 , the isolation unit 53 includes a conversion unit M1 and a transformer B1. The conversion unit is used to convert the direct current output by the third voltage-regulating element L2 into alternating current and transmit it to the primary coil of the transformer. The secondary coil of the transformer is used to be electrically connected to the communication circuit 51. The primary coil and the secondary coil are both grounded and the grounding grids are different to prevent ground wire crosstalk. The transformer is used to perform isolation processing on high-frequency signals.

[0061] Specifically, the voltage V4 output by the third voltage-regulating element L2 is a DC source, and the transformer B1 cannot process it. Therefore, a conversion unit M1 needs to be set up. The conversion unit M1 converts the voltage V4 into an AC source and then outputs it to the transformer B1. The transformer B1 outputs the voltage V41 to the communication circuit 51 to supply power to the communication circuit 51. The grounding grids of the primary coil and the secondary coil can be the plate GND and the isolated ground V0 respectively.

[0062] Figure 8 shows the structure of a specific lithium battery protection board power supply system. The structure of the lithium battery protection board power supply system of the present application includes, but is not limited to Figure 8 the structure of the lithium battery protection board power supply system shown. In the lithium battery protection board power supply system of the present application, the structures of each power supply module and the switching unit all include, but are not limited to, the structures described in the above embodiments.

[0063] The switchability of the second power supply module 2 and the presence of the DC conversion unit U1 enable the second current-limiting resistor and the second switching unit 52 not to bear too high a voltage drop, avoiding the problem of the temperature of the second current-limiting resistor and the first switching element soaring when the power-consuming communication circuit 51 and the second logic circuit 21 are working. This also reduces the temperature control requirements and the packaging margin requirements of the second power supply module 2.

[0064] In a second aspect, the present application provides a lithium battery protection board, including the lithium battery protection board power supply system provided in the first aspect, which has all the advantages of the above-mentioned lithium battery protection board power supply system and will not be elaborated here. The lithium battery protection board is an intelligent software protection board.

[0065] In some embodiments, the lithium battery protection board further includes a micro control unit 11, a first logic circuit 12, and a second logic circuit 21 that are electrically connected to the lithium battery protection board power supply system. The specific connection manners of the micro control unit 11, the first logic circuit 12, and the second logic circuit 21 to the lithium battery protection board power supply system can be referred to the description in the first aspect and will not be elaborated here.

[0066] In some embodiments, the lithium battery protection board further includes a communication circuit 51 and a signal circuit 41 that are electrically connected to the lithium battery protection board power supply system. The specific connection manners of the communication circuit 51 and the signal circuit 41 to the lithium battery protection board power supply system can be referred to the description in the first aspect and will not be elaborated here.

[0067] In a third aspect, the present application provides a lithium battery, including the lithium battery protection board provided in the second aspect, which has all the advantages of the above-mentioned lithium battery protection board and will not be elaborated here.

[0068] In the description of this specification, the description with reference to terms such as "some embodiments" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0069] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered that the scope described in this specification.

[0070] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A power supply system for a lithium battery protection board, characterized in that, it includes a first power supply module, a second power supply module and a first voltage stabilizing element. The input ends of the first power supply module and the second power supply module are electrically connected to the positive electrode of the battery pack. The output ends of the first power supply module and the second power supply module are both connected to the input end of the first voltage stabilizing element. The output end of the first voltage stabilizing element is used to be electrically connected to a micro control unit and a first logic circuit. The output end of the second power supply module is also used to be electrically connected to a second logic circuit; the output power of the second power supply module is greater than the output power of the first power supply module, and the on / off of the second power supply module is controlled by the micro control unit; when the second power supply module is turned off, the first power supply module supplies power to the micro control unit and the first logic circuit, so that the protection board enters the sleep state; when the second power supply module is turned on, the second power supply module and the first power supply module supply power to the micro control unit and the first logic circuit, and the second power supply module also supplies power to the second logic circuit, so that the protection board works normally.

2. The power supply system for a lithium battery protection board according to claim 1, characterized in that, the first power supply module includes a first current limiting element and a voltage adjustment unit. The positive electrode of the battery pack, the first current limiting element, the voltage adjustment unit and the first voltage stabilizing element are connected in series in sequence. The voltage adjustment unit is used to control the voltage value output to the first voltage stabilizing element.

3. The power supply system for a lithium battery protection board according to claim 2, characterized in that, the voltage adjustment unit includes a power device, a second voltage stabilizing element and a first voltage dividing element; the input electrode of the power device is electrically connected to the first current limiting element, the output electrode of the power device is electrically connected to the input end of the first voltage stabilizing element, the control electrode of the power device is electrically connected to the negative electrode of the second voltage stabilizing element, and the positive electrode of the second voltage stabilizing element is grounded; the first current limiting element, the first voltage dividing element and the negative electrode of the second voltage stabilizing element are connected in series in sequence.

4. The power supply system for a lithium battery protection board according to claim 1, characterized in that, the second power supply module includes a second current limiting element, a first switching unit and a DC conversion unit. The positive electrode of the battery pack, the second current limiting element, the first switching unit, the DC conversion unit and the first voltage stabilizing element are connected in series in sequence. The output end of the DC conversion unit is also used to be electrically connected to the second logic circuit. The first switching unit is controlled by the micro control unit to control the switch of the second power supply module.

5. The power supply system for a lithium battery protection board according to claim 4, characterized in that, The first switching unit includes a first switching element, a second switching element, a second voltage dividing element, and a third voltage dividing element; an input electrode of the first switching element is electrically connected to the second current limiting element, and an output electrode of the first switching element is electrically connected to an input end of the DC conversion unit; a control electrode of the second switching element is used to be electrically connected to the micro control unit, an output electrode of the second switching element is grounded, and an input electrode of the second switching element, the third voltage dividing element, and a control electrode of the first switching element are connected in series in sequence; the second current limiting element, the second voltage dividing element, and the third voltage dividing element are connected in series in sequence.

6. The power supply system for a lithium battery protection board according to claim 4, wherein, the second power supply module further includes an anti-reverse connection diode, a positive electrode of the anti-reverse connection diode is electrically connected to an output end of the DC conversion unit, and a negative electrode of the anti-reverse connection diode is electrically connected to an input end of the first voltage stabilizing element.

7. The power supply system for a lithium battery protection board according to any one of claims 1-6, wherein, it further includes a signal switching module, an input end of the signal switching module is electrically connected to an output end of the first voltage stabilizing element, and the signal switching module is used to be electrically connected to a signal circuit and the micro control unit to control the switch of the signal circuit.

8. The power supply system for a lithium battery protection board according to claim 7, wherein, the signal switching module includes a third switching element, a fourth voltage dividing element, and a fifth voltage dividing element, an input electrode of the third switching element is electrically connected to an output end of the first voltage stabilizing element, an output electrode of the third switching element is used to be electrically connected to the signal circuit, and a control electrode of the third switching element is electrically connected to the fifth voltage dividing element; an output end of the first voltage stabilizing element, the fourth voltage dividing element, and the fifth voltage dividing element are connected in series in sequence; the fifth voltage dividing element is further used to be electrically connected to the micro control unit.

9. The power supply system for a lithium battery protection board according to any one of claims 1-6, wherein, it further includes a communication switching module, an input end of the communication switching module is electrically connected to an output end of the second power supply module, and the communication switching module is used to be electrically connected to a communication circuit and the micro control unit to control the switch of the communication circuit.

10. The power supply system for a lithium battery protection board according to claim 9, wherein, the communication switching module includes a second switching unit, a third voltage stabilizing element, and an isolation unit, an output end of the second power supply module, the second switching unit, the third voltage stabilizing element, and the isolation unit are connected in series in sequence, the isolation unit is further used to be electrically connected to the communication circuit, the second switching unit is further used to be electrically connected to the micro control unit, and the isolation unit is used to perform isolation processing on a communication signal output by the third voltage stabilizing element.

11. The power supply system for a lithium battery protection board according to claim 10, wherein, The second switching unit includes a fourth switching element, a fifth switching element, a sixth voltage dividing element, and a seventh voltage dividing element; an input electrode of the fourth switching element is electrically connected to an output end of the second power supply module, and an output electrode of the fourth switching element is electrically connected to an input end of the third voltage stabilizing element; a control electrode of the fifth switching element is used for being electrically connected to the micro control unit, an output electrode of the fifth switching element is grounded, and an input electrode of the fifth switching element, the seventh voltage dividing element, and a control electrode of the fourth switching element are connected in series in sequence; an output end of the second power supply module, the sixth voltage dividing element, and the seventh voltage dividing element are connected in series in sequence.

12. The lithium battery protection board power supply system according to claim 10, wherein, the isolation unit includes a conversion unit and a transformer, the conversion unit is used for converting the direct current output by the third voltage stabilizing element into alternating current and transmitting the alternating current to a primary coil of the transformer, a secondary coil of the transformer is used for being electrically connected to the communication circuit, and both the primary coil and the secondary coil are grounded and the grounding grids are different.

13. A lithium battery protection board, wherein, it includes the lithium battery protection board power supply system according to any one of claims 1-12.

14. A lithium battery, wherein, it includes the lithium battery protection board according to claim 13.

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