12V starting lithium battery pack capable of meeting consistent charging tail end voltage

Abstract

The utility model relates to the technical field of lithium battery packs, and discloses a 12V starting lithium battery pack capable of meeting the consistent charging tail end voltage. A battery management module; a charging management module; a charging protection module; a voltage balancing module; the voltage balancing module can ensure that the voltage of the charging tail end of each single lithium battery in the lithium battery pack is kept consistent, the voltage difference between the lithium batteries is prevented from being too large, the charging protection module and the battery management module monitor the voltage and current states of the batteries in real time, and when the lithium batteries are overcharged, overdischarged, short-circuited, overcurrent and the like, the lithium batteries can be protected from being damaged. The safety performance of the lithium battery pack is improved by rapidly cutting off a power supply or adjusting a charging and discharging strategy; the voltage equalization module also performs equalization charging on the lithium battery, thereby effectively avoiding the unbalance problem of the battery, reducing the voltage and capacity difference between the single batteries, reducing the internal resistance of the battery, and prolonging the service life of the battery.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery pack technology, specifically a 12V starting lithium battery pack that meets the requirement of consistent charging end voltage. Background Technology

[0002] Lithium-ion batteries are a type of battery that uses lithium metal or lithium alloys as the positive / negative electrode material and a non-aqueous electrolyte solution. A lithium-ion battery pack consists of multiple lithium-ion cells connected in series or parallel to provide the required voltage and capacity. Compared to traditional lead-acid batteries, lithium-ion battery packs have higher energy density, longer lifespan, and lower self-discharge rate.

[0003] A search revealed that patent application number CN201820291003.9 discloses a 12V lithium battery automotive starting power supply, comprising: a lithium battery module for providing starting voltage to the vehicle load, the lithium battery modules being connected in series to form a 12V voltage; a backup battery module for providing emergency starting voltage to the vehicle load; a relay for controlling the opening and closing of the backup battery module; a power display module for displaying the power level of the lithium battery module; and a switch for controlling the opening and closing of the power display module and the relay. Both the lithium battery module and the backup battery module are connected to the vehicle load. The relay and switch are sequentially connected between the backup battery module and the vehicle load, and the power display module is connected between the switch and the vehicle load. This 12V lithium battery automotive starting power supply can still start normally after over-discharge, allows for real-time monitoring of the power system's power level, and has a simple structure, which is beneficial for mass production.

[0004] The safety performance of current 12V starting lithium battery packs needs to be improved. There are large voltage differences between lithium batteries, and the charging process is prone to overcharging, over-discharging, short circuits, and overcurrent, which reduces the safety of lithium battery packs. Uneven charging strategies also reduce battery life. Therefore, we need to propose a 12V starting lithium battery pack that ensures consistent voltage at the end of charging. Utility Model Content

[0005] The purpose of this invention is to provide a 12V starting lithium battery pack that ensures consistent charging terminal voltage. The voltage balancing module ensures that the charging terminal voltage of each individual lithium battery in the pack remains consistent, avoiding excessive voltage differences between lithium batteries. The charging protection module and battery management module monitor the voltage and current status of the batteries in real time. When the lithium battery experiences overcharging, over-discharging, short circuit, or overcurrent, the power supply is quickly cut off or the charging and discharging strategy is adjusted to improve the safety performance of the lithium battery pack. The voltage balancing module also performs equal charging of the lithium batteries, effectively avoiding battery imbalance, reducing voltage and capacity differences between individual battery cells, lowering battery internal resistance, and extending battery life, thereby solving the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a 12V starting lithium battery pack that meets the requirement of consistent charging end voltage, comprising:

[0007] A battery pack module consisting of multiple connected individual lithium batteries;

[0008] The battery management module is responsible for monitoring the status of the battery pack modules;

[0009] A charging management module responsible for controlling the charging process and ensuring that the lithium battery is charged with rated current and voltage;

[0010] A charging protection module used to promptly cut off the circuit when an abnormal situation occurs during the charging process of the battery pack module;

[0011] A voltage equalization module used to balance the voltage differences between individual lithium batteries during charging.

[0012] The battery management module, charging management module, charging protection module, and voltage balancing module are all electrically connected to the battery pack module, and the charging management module, charging protection module, and voltage balancing module are all electrically connected to the battery management module.

[0013] Preferably, the battery management module includes a chip U11, pin 1 of which is connected to a resistor R11 and a diode D11 connected in series, and a capacitor E11 and a capacitor C11 connected in parallel. One end of the diode D11 is connected to a fuse F1.

[0014] Pin 2 of the chip U11 is connected to a resistor R21, as well as a diode DZ1 and a capacitor C41 connected in parallel.

[0015] Pin 3 of the chip U11 is connected to a resistor R71, as well as a diode DZ2 and a capacitor C51 connected in parallel.

[0016] The chip U11 has a resistor R15 connected to its 4th pin, as well as a diode DZ3 and a capacitor C61 connected in parallel.

[0017] Pin 5 of the chip U11 is connected to a resistor R20, as well as a diode DZ4 and a capacitor C71 connected in parallel.

[0018] The chip U11 has a resistor R27 connected to pin 6, as well as a diode DZ5 and a capacitor C101 connected in parallel.

[0019] Preferably, the battery management module further includes a MOSFET Q3. A resistor R19 is connected between pin 8 of the chip U11 and the drain of the MOSFET Q3. Resistors R23 and R28 are connected to the source of the MOSFET Q3. A capacitor C81 is connected between R23 and R28. Resistors R21 and R25 are connected to the gate of the MOSFET Q3. Resistors R25 and R28 are connected.

[0020] Preferably, the charging management module includes a chip U58 and a MOSFET Q2. A capacitor C224 and a capacitor C225 are connected in parallel to the terminals of pins 4 and 8 of the chip U58. A light-emitting diode (LED) LED10 is connected to pin 6 of the chip U58, and a light-emitting diode (LED) LED9 is connected to pin 7 of the chip U58. A resistor R92 is connected between the terminals of LED9 and LED10 and pin 4 of the chip U58. Pin 5 of the chip U58 is connected to the source of the MOSFET Q2. A capacitor C226 and a capacitor C227 are connected in parallel between pins 5 and 9 of the chip U58.

[0021] Preferably, the charging protection module includes a chip U3, with a diode D41 connected to the input voltage at pin 8 of the chip U3, a light-emitting diode D42 and a resistor R43 connected in series at pin 6 of the chip U3, and a capacitor C43 and a light-emitting diode D43 connected in series at pin 1 of the chip U3. The light-emitting diode D43 is connected to the connection terminal of the light-emitting diode D42 and the resistor R43.

[0022] A capacitor C41 and a capacitor C42 are connected in parallel between pins 8 and 9 of the chip U3, and an inductor L14, a resistor R42 and a capacitor C44 are connected in series between pins 7 and 9 of the chip U3.

[0023] Preferably, the voltage equalization module includes a chip U1 connected to an inductor L1, a connector J1 and a connector J3 connected to the chip U1, and a connector J2 connected to the inductor L1.

[0024] Pin 2 of connector J1 is connected to pin 2 of chip U1. Capacitors C1, C2, C3, and C4 are connected in parallel between pins 1 and 2 of connector J1. Capacitor C13, resistors R1, R2, and R3 are connected in series between pins 2 of chip U1.

[0025] Preferably, pin 8 of chip U1 is connected to pin 1 of inductor L1, pin 7 of chip U1 is connected to pin 1 of connector J3, pin 3 of inductor L1 is connected to pin 2 of connector J3, capacitors C8, C9, and C10 are connected in parallel between pins 1 and 2 of connector J3, and diode D25 is connected between pins 7 and 8 of chip U1.

[0026] A capacitor C101 and a resistor R101 are connected in series between pins 2 and 4 of the inductor L1. A capacitor C14, a capacitor C6, and a capacitor C7 are connected in parallel between pins 1 and 2 of the connector J2. A diode D15 is connected between pin 4 of the inductor L1 and pins 1 and 2 of the connector J2. Pin 3 of the inductor L1 is connected to pin 1 of the connector J2.

[0027] Compared with the prior art, the beneficial effects of this utility model are:

[0028] 1. The voltage balancing module of this utility model can ensure that the charging end voltage of each individual lithium battery in the lithium battery pack is consistent, avoiding excessive voltage differences between lithium batteries. The charging protection module and the battery management module can monitor the voltage and current status of the battery in real time. When the lithium battery is overcharged, over-discharged, short-circuited, or overcurrent, the power supply is quickly cut off or the charging and discharging strategy is adjusted to improve the safety performance of the lithium battery pack.

[0029] 2. The voltage balancing module of this utility model also performs balanced charging of lithium batteries, effectively avoiding battery imbalance, reducing voltage and capacity differences between individual battery cells, reducing battery internal resistance, and extending battery life. Attached Figure Description

[0030] Figure 1 This is a system block diagram of the present invention;

[0031] Figure 2 This is a circuit diagram of the battery management module of this utility model;

[0032] Figure 3 This is a circuit diagram of the charging management module of this utility model;

[0033] Figure 4 This is a circuit diagram of the charging protection module of this utility model;

[0034] Figure 5 This is the circuit diagram of the voltage equalization module of this utility model. Detailed Implementation

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] Please see Figure 1-5This utility model provides a technical solution: a 12V starting lithium battery pack that meets the requirement of consistent charging end voltage, comprising:

[0037] A battery pack module is composed of multiple individual lithium batteries connected together; the battery pack module is composed of multiple individual lithium batteries combined in series and / or parallel to provide the required 12V voltage and sufficient capacity; compared with traditional lead-acid batteries, lithium battery packs have higher energy density, longer service life, lower self-discharge rate and more environmentally friendly characteristics.

[0038] The battery management module is responsible for monitoring the status of the battery pack modules; this includes monitoring parameters such as voltage, current, and temperature of each individual battery cell to ensure the battery pack operates within safe ranges. It can also perform equalization control to reduce voltage differences between battery cells. This improves the efficiency, safety, and reliability of the battery pack, and extends its lifespan.

[0039] The battery management module includes a chip U11. Pin 1 of the chip U11 is connected to a resistor R11 and a diode D11 connected in series, and a capacitor E11 and a capacitor C11 connected in parallel. One end of the diode D11 is connected to a fuse F1.

[0040] Pin 2 of the chip U11 is connected to a resistor R21, as well as a diode DZ1 and a capacitor C41 connected in parallel.

[0041] Pin 3 of the chip U11 is connected to a resistor R71, as well as a diode DZ2 and a capacitor C51 connected in parallel.

[0042] The chip U11 has a resistor R15 connected to its 4th pin, as well as a diode DZ3 and a capacitor C61 connected in parallel.

[0043] Pin 5 of the chip U11 is connected to a resistor R20, as well as a diode DZ4 and a capacitor C71 connected in parallel.

[0044] The chip U11 has a resistor R27 connected to pin 6, as well as a diode DZ5 and a capacitor C101 connected in parallel.

[0045] The battery management module also includes a MOSFET Q3. A resistor R19 is connected between pin 8 of the chip U11 and the drain of the MOSFET Q3. Resistors R23 and R28 are connected to the source of the MOSFET Q3. A capacitor C81 is connected between R23 and R28. Resistors R21 and R25 are connected to the gate of the MOSFET Q3. Resistors R25 and R28 are connected together.

[0046] The rated current of fuse F1 is 100A, which serves as overcurrent protection. When the current in the circuit exceeds the rated value, fuse F1 will melt and disconnect the circuit to prevent circuit components from being damaged due to overcurrent.

[0047] Diode D11 is a fast-switching diode used to prevent the voltage of the lithium battery pack from flowing into the circuit in reverse, thus providing reverse protection.

[0048] Diodes DZ1-DZ5 are Zener diodes, connected in series with each individual lithium battery cell to protect the battery and prevent it from overvoltage.

[0049] Chip U11 has functions such as battery voltage monitoring and equalization control. Pins VB0-VB5 of chip U11 are connected to individual lithium batteries for monitoring battery voltage. MOSFET Q3 is used for switching control or signal amplification.

[0050] The charging management module is responsible for controlling the charging process and ensuring that the lithium battery is charged with the rated current and voltage. It has efficient, safe and stable charging performance, can adapt to charging requirements with different voltages and currents, and protects the battery pack from damage such as overcharging.

[0051] The charging management module includes a chip U58 and a MOSFET Q2. Capacitors C224 and C225 are connected in parallel to pins 4 and 8 of the chip U58. A light-emitting diode (LED10) is connected to pin 6 of the chip U58, and an LED9 is connected to pin 7 of the chip U58. A resistor R92 is connected between the terminals of LED9 and LED10 and pin 4 of the chip U58. Pin 5 of the chip U58 is connected to the source of the MOSFET Q2. Capacitors C226 and C227 are connected in parallel between pins 5 and 9 of the chip U58.

[0052] The U58 chip integrates multiple charging modes such as trickle charging, constant current charging, and constant voltage charging, and has functions such as charging status indication and battery temperature monitoring; capacitors C224 and C225 are used for power supply filtering to filter out high-frequency and low-frequency noise in the VCD input power supply and ensure the stability of the chip power supply; capacitors C226 and C227 filter the voltage at the battery terminal to stabilize the battery voltage.

[0053] LED9 is used to indicate the charging status. This LED is usually lit when the battery is charging. LED10 is used to indicate that charging is complete. This LED is usually lit when the battery is fully charged.

[0054] Resistor R92 limits the current to prevent excessive current from damaging the LED. Resistor R93 sets the charging current, which is inversely proportional to the resistance of R93. Diode D3 prevents reverse voltage from flowing from VCC to VCD, providing reverse protection. MOSFET Q2 controls the battery charging circuit, switching the charging circuit on or off under certain conditions (such as overcurrent or overvoltage protection).

[0055] A charging protection module is used to promptly cut off the circuit when abnormal conditions occur during the charging process of the battery pack module. This module is designed to disconnect the circuit when abnormal conditions such as overcharging, over-discharging, short circuits, or overcurrent occur in the battery pack, preventing damage to the battery pack or safety accidents. It improves the safety and reliability of the battery pack and protects both the battery pack and the electrical equipment from damage.

[0056] The charging protection module includes a chip U3. Pin 8 of the chip U3 is connected to a diode D41 that is connected to the input voltage. Pin 6 of the chip U3 is connected in series with a light-emitting diode D42 and a resistor R43. Pin 1 of the chip U3 is connected in series with a capacitor C43 and a light-emitting diode D43. The light-emitting diode D43 is connected to the connection terminal of the light-emitting diode D42 and the resistor R43.

[0057] A capacitor C41 and a capacitor C42 are connected in parallel between pins 8 and 9 of the chip U3, and an inductor L14, a resistor R42 and a capacitor C44 are connected in series between pins 7 and 9 of the chip U3.

[0058] Capacitor C41 is used to filter out low-frequency ripple in the power supply, and capacitor C42 is used to filter out high-frequency noise, making the power supply transmitted to chip U3 more stable. Resistor R41 is used to set the input voltage detection or voltage division function, resistor R42 is used for current detection and feedback of charging current information to chip U3, and resistor R43 is used to set status indicator parameters, which, together with LED D42, display charging status and other information.

[0059] LED D42 is used to indicate the charging status. It may light up when the battery is charging and may indicate different statuses when charging is complete. LED D43 is used for voltage regulation or voltage clamping to protect the relevant pins of the chip from excessive voltage. Inductor L14 acts as an energy storage element in the charging circuit. It works with the internal switching circuit of the chip to realize the conversion and transfer of energy and to stabilize the charging current.

[0060] A voltage balancing module is used to balance the voltage differences between individual lithium-ion cells during charging; ensuring that each cell is fully charged and maintains a consistent terminal voltage. This improves the overall performance and consistency of the battery pack, extending its lifespan.

[0061] The voltage equalization module includes a chip U1 connected to an inductor L1, a connector J1 and a connector J3 connected to the chip U1, and a connector J2 connected to the inductor L1.

[0062] Pin 2 of connector J1 is connected to pin 2 of chip U1. Capacitors C1, C2, C3, and C4 are connected in parallel between pins 1 and 2 of connector J1. Capacitor C13, resistors R1, R2, and R3 are connected in series between pins 2 of chip U1.

[0063] Pin 8 of chip U1 is connected to pin 1 of inductor L1, pin 7 of chip U1 is connected to pin 1 of connector J3, pin 3 of inductor L1 is connected to pin 2 of connector J3, capacitors C8, C9 and C10 are connected in parallel between pins 1 and 2 of connector J3, and diode D25 is connected between pins 7 and 8 of chip U1.

[0064] A capacitor C101 and a resistor R101 are connected in series between pins 2 and 4 of the inductor L1. A capacitor C14, a capacitor C6, and a capacitor C7 are connected in parallel between pins 1 and 2 of the connector J2. A diode D15 is connected between pin 4 of the inductor L1 and pins 1 and 2 of the connector J2. Pin 3 of the inductor L1 is connected to pin 1 of the connector J2.

[0065] Capacitors C1, C2, C3, and C4 are connected in parallel at the input power supply for filtering. Capacitors C1, C2, and C3 filter out low-frequency ripple, while capacitor C4 filters out high-frequency noise, making the voltage input to chip U1 more stable. Resistor R6 is a startup resistor, used to provide an initial high-level signal to the enable pin of chip U1 upon power-up, starting chip U1 to work. Resistor R5 is used to set the switching frequency of chip U1, and capacitor C13 is used for stable startup and to cooperate with other components.

[0066] Resistors R4 and R7 form a voltage divider circuit, which is connected between the output voltage terminal and the FB pin of chip U1. This circuit is used to feed the output voltage back to chip U1, so that chip U1 can adjust the output voltage according to the feedback signal and achieve voltage regulation control.

[0067] Capacitors C11 and C12 are used to compensate for the phase and gain of the feedback loop, ensuring the stability of the feedback loop and preventing output voltage oscillations. Inductor L1 acts as an energy storage element, storing energy when the internal switching transistor of chip U1 is turned on and releasing energy when the switching transistor is turned off, maintaining the stability of the output voltage. Diodes D15 and D25 are used in the +12V and -12V output circuits respectively, serving as rectification functions to prevent reverse output voltage and ensure the correct polarity of the output voltage.

[0068] The battery management module, charging management module, charging protection module, and voltage balancing module are all electrically connected to the battery pack module, and the charging management module, charging protection module, and voltage balancing module are all electrically connected to the battery management module.

[0069] Individual battery cells are connected in series and / or parallel to form a lithium battery pack. The positive and negative terminals of the lithium battery pack are typically connected to the battery management module, charging management module, and charging protection module via wires.

[0070] The battery management module connects to each individual battery cell in the battery pack via sensors to monitor the pack's status in real time. Simultaneously, it connects to the charging management module and the charging protection module to receive charging commands and provide battery pack status information.

[0071] The charging management module's input is connected to an external power source, and its output is connected to the battery pack. It also connects to the battery management module to receive charging control commands and adjust charging parameters based on the battery pack's status.

[0072] The charging protection module is connected to the positive and negative terminals of the lithium battery in the lithium battery pack module, and monitors the current and voltage of the lithium battery pack in real time. When an abnormal situation occurs, the charging protection module will quickly cut off the circuit and connect to the battery management module so that the battery management module can record the abnormal information.

[0073] The voltage balancing module is connected to each individual lithium battery cell in the battery pack, and achieves balancing control by adjusting the charging current or voltage of each cell. It is also connected to the battery management module to receive balancing control commands.

[0074] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A 12V starting lithium battery pack that meets the end of charge voltage consistency, characterized in that, The application relates to a battery pack module comprising: a plurality of single lithium batteries connected together; a battery management module responsible for monitoring the state of the battery pack module; a charging management module responsible for controlling the charging process and ensuring that the lithium batteries are charged at rated current and voltage; a charging protection module for timely cutting off the circuit when abnormal conditions occur during the charging process of the battery pack module; a voltage balancing module for balancing the voltage difference between the single lithium batteries during the charging process; the battery management module, the charging management module, the charging protection module and the voltage balancing module are electrically connected with the battery pack module, and the charging management module, the charging protection module and the voltage balancing module are electrically connected with the battery management module.

2. The 12V starting lithium battery pack satisfying consistent charge end voltage according to claim 1, characterized in that: The battery management module comprises a chip U11, one pin of the chip U11 is connected with a resistor R11 and a diode D11 arranged in series, a capacitor E11 and a capacitor C11 arranged in parallel, one end of the diode D11 is connected with a fuse F1; a second pin of the chip U11 is connected with a resistor R21 and a diode DZ1 and a capacitor C41 arranged in parallel; a third pin of the chip U11 is connected with a resistor R71 and a diode DZ2 and a capacitor C51 arranged in parallel; a fourth pin of the chip U11 is connected with a resistor R15 and a diode DZ3 and a capacitor C61 arranged in parallel; a fifth pin of the chip U11 is connected with a resistor R20 and a diode DZ4 and a capacitor C71 arranged in parallel; a sixth pin of the chip U11 is connected with a resistor R27 and a diode DZ5 and a capacitor C101 arranged in parallel.

3. The 12V starting lithium battery pack satisfying consistent charge end voltage of claim 2, wherein: The battery management module further comprises a MOS tube Q3, a resistor R19 is connected between an eighth pin of the chip U11 and a drain of the MOS tube Q3, a source of the MOS tube Q3 is respectively connected with a resistor R23 and a resistor R28, a capacitor C81 is connected between the R23 and the resistor R28, a gate of the MOS tube Q3 is respectively connected with a resistor R21 and a resistor R25, and the resistor R25 is connected with the resistor R28.

4. The 12V starting lithium battery pack satisfying consistent charge end voltage of claim 1, wherein: The charging management module comprises a chip U58 and a MOS tube Q2, parallel-connected capacitors C224 and C225 are connected on wiring terminals of a fourth pin and an eighth pin of the chip U58, a sixth pin of the chip U58 is connected with a light-emitting diode LED10, a seventh pin of the chip U58 is connected with a light-emitting diode LED9, a resistor R92 is connected between wiring terminals of the light-emitting diode LED9 and the light-emitting diode LED10 and the fourth pin of the chip U58, a source of the MOS tube Q2 is connected with a fifth pin of the chip U58, and capacitors C226 and C227 are connected in parallel between the fifth pin and a ninth pin of the chip U58.

5. The 12V starting lithium battery pack meeting consistent charge end voltage according to claim 1, characterized in that: The charging protection module comprises a chip U3, an eighth pin of the chip U3 is connected with a diode D41 for inputting voltage, a light-emitting diode D42 and a resistor R43 are connected in series on a sixth pin of the chip U3, a capacitor C43 and a light-emitting diode D43 are connected in series on a first pin of the chip U3, and the light-emitting diode D43 is connected at a connection terminal of the light-emitting diode D42 and the resistor R43. The capacitor C41 and the capacitor C42 are connected in parallel between the 8th pin and the 9th pin of the chip U3, and the inductor L14, the resistor R42 and the capacitor C44 are connected in series between the 7th pin and the 9th pin of the chip U3.

6. The 12V starting lithium battery pack meeting consistent charge end voltage according to claim 1, characterized in that: The voltage equalization module comprises the chip U1 and the inductor L1 connected, the connector J2 connected with the inductor L1, the connector J1 and the connector J3 connected with the chip U1; The 2nd pin of the connector J1 is connected with the 2nd pin of the chip U1, and the capacitor C1, the capacitor C2, the capacitor C3 and the capacitor C4 are connected in parallel between the 1st pin and the 2nd pin of the connector J1, and the capacitor C13, the resistor R1, the resistor R2 and the resistor R3 are connected in series with the 2nd pin of the chip U1.

7. The 12V starting lithium battery pack meeting consistent charge end voltage according to claim 6, characterized in that: The 8th pin of the chip U1 is connected with the 1st pin of the inductor L1, the 7th pin of the chip U1 is connected with the 1st pin of the connector J3, the 3rd pin of the inductor L1 is connected with the 2nd pin of the connector J3, the capacitor C8, the capacitor C9 and the capacitor C10 are connected in parallel between the 1st pin and the 2nd pin of the connector J3, and the diode D25 is connected between the 7th pin and the 8th pin of the chip U1. The capacitor C101 and the resistor R101 are connected in series between the 2nd pin and the 4th pin of the inductor L1, the capacitor C14, the capacitor C6 and the capacitor C7 are connected in parallel between the 1st pin and the 2nd pin of the connector J2, the diode D15 is connected between the 4th pin of the inductor L1 and the 1st pin and the 2nd pin of the connector J2, and the 3rd pin of the inductor L1 is connected with the 1st pin of the connector J2.

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