Lithium battery intelligent charging system

Abstract

The utility model relates to the technical field of battery charging, in particular to a lithium battery intelligent charging system, which comprises a power supply unit, a lithium battery charging unit and a lithium battery protection unit, system input voltage MHVDD is connected to a fifth pin VIN port of a DC-DC chip UQ1, one end of a resistor RQ1 is connected to the system input voltage MHVDD, the other end of the resistor RQ1 and one end of a resistor RQ2 are connected to a fourth pin EN port of the DC-DC chip UQ1, and the other end of the resistor RQ2 is connected to a fifth pin VIN port of the DC-DC chip UQ1. The other end of the resistor RQ2 and a second pin GND port of the DC-DC chip UQ1 are jointly connected to a system reference ground GND. The battery protection device has multiple battery protection functions such as over-charge protection, over-discharge protection, over-current protection and the like, so that the battery is effectively prevented from being damaged or causing safety accidents; the lithium battery has a wide voltage and current input range, and can adapt to lithium batteries of different brands and models.

Description

Technical Field

[0001] The utility model relates to the technical field of battery charging, in particular to an intelligent charging system for lithium batteries. Background Art

[0002] The demand for rechargeable lithium batteries in overseas electric energy meters is becoming increasingly prominent. Since electric energy meters need to operate stably for a long time, traditional batteries cannot meet the long-term power supply requirements, so rechargeable lithium batteries have become an ideal choice. This type of battery not only has a long service life, but also can be charged cyclically, reducing the frequency and cost of battery replacement. At the same time, the high energy density and lightweight characteristics of lithium batteries also meet the environmental protection and energy-saving requirements of overseas markets. In order to meet this demand in overseas markets, electric energy meter manufacturers are actively developing and applying rechargeable lithium battery technology to enhance the competitiveness and market share of their products. With the continuous advancement of technology and the expansion of the market, the application of rechargeable lithium batteries in the field of electric energy meters will be more extensive. At this stage, there are some shortcomings in the circuits for charging lithium batteries. On the one hand, some circuits may have the problem of high power consumption, resulting in a certain amount of energy loss during the charging process. On the other hand, the charging speed of some circuits may be subject to certain restrictions, which cannot meet the user's demand for fast charging. Utility Model Content

[0003] The utility model aims to solve the above problems and provides a lithium battery intelligent charging system, which adopts the following technical solutions:

[0004] A lithium battery intelligent charging system, comprising a power supply unit and a lithium battery charging unit, wherein the power supply unit adopts an LDO circuit;

[0005] The lithium battery charging unit includes capacitor C1, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, resistor R1, resistor R3, resistor R4, resistor R5 and lithium battery charging chip U1. Capacitor C3 and capacitor C4 are connected in parallel between the 2-pin GND port and the 3-pin OUT port of the lithium battery charging chip U1. The 2-pin GND port is connected to the system reference ground GND, and the 3-pin OUT port is connected to the lithium battery positive electrode voltage VBAT. One end of the chip resistor R4 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the lithium battery voltage sampling signal Battery_ADC. After the resistor R5 and capacitor C8 are connected in parallel, one end is connected to the battery voltage sampling signal Battery_ADC. The other end is connected to the system reference ground GND, capacitor C1 is connected in parallel between the 6-pin CHGB port of the lithium battery charging chip U1 and the system reference ground GND, the 6-pin CHGB port of the chip U1 is connected to the charging status signal CHGB, the chip resistor R1 is connected in series between the charging status signal CHGB and the lithium battery charging unit working voltage DVDD, the 5-pin IN port of the lithium battery charging chip U1 is connected to the lithium battery charging voltage B+5V, capacitor C6 and capacitor C7 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, the 4-pin PWM port of the lithium battery charging chip U1 is connected to the adjustment signal PWM, and resistor R3 and capacitor C5 are connected in parallel between the adjustment signal PWM and the system reference ground GND.

[0006] On the basis of the above scheme, the power supply unit includes capacitor CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, DC-DC chip UQ1, diode DQ11, inductor LQ1 and LD0 chip UQ2, the system input voltage MHVDD is connected to the 5-pin VIN port of the DC-DC chip UQ1, and the voltage One end of resistor RQ1 is connected to the system input voltage MHVDD, and the other end and one end of resistor RQ2 are connected to the EN port of DC-DC chip UQ14-pin. The other end of resistor RQ2 and the 2-pin GND port of DC-DC chip UQ1 are connected to the system reference ground GND. Capacitors CQ4, CQ5, and CQ6 are connected in parallel between the system input voltage MHVDD and the system reference ground GND. Capacitor CQ1 is connected in parallel between the 6-pin SW port and the 1-pin BST port of DC-DC chip UQ1. The port is connected to the cathode of the diode DQ11 and one end of the inductor LQ1, the anode of the diode DQ11 is connected to the system reference ground GND, the other end of the inductor LQ1 is connected to the lithium battery charging voltage B+5V, the capacitors CQ2, CQ3, CQ8 and CQ10 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, one end of the resistor RQ5 is connected to the lithium battery charging voltage B+5V, and the other end is connected to one end of the resistor RQ4, and the other end of the resistor RQ4 is connected to one end of the resistor RQ3. Connect to the 3-pin FB port of the DC-DC chip UQ1, the other end of the resistor RQ3 is connected to the system reference ground GND, the 2-pin VIN port of the LDO chip UQ2 is connected to the lithium battery charging voltage B+5V, the 1-pin GND port of the LDO chip UQ2 is connected to the system reference ground GND, the 3-pin VOUT port of the LDO chip UQ2 is connected to the lithium battery charging unit working voltage DVDD, and the capacitors CQ7 and CQ9 are connected in parallel between the lithium battery charging unit working voltage DVDD and the system reference ground GND;

[0007] On the basis of the above scheme, a lithium battery protection unit is also included, which includes a resistor R2, a capacitor C2, a battery short-circuit point JV1, a rechargeable lithium battery BAT1 and a lithium battery protection chip U2, one end of the resistor R2 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the 1-pin PCKP port of the lithium battery protection chip U2, the 2-pin, 3-pin and 7-pin PCKN ports of the lithium battery protection chip U2 are connected to the system reference ground GND, the capacitor C2 is connected in parallel between the protection unit reference ground BGND and the 6-pin BYPS port of the lithium battery protection chip U2, the 4-pin and 5-pin BATN ports of the lithium battery protection chip U2 are connected to the protection unit reference ground BGND, one end of the battery short-circuit point JV1 is connected to the lithium battery positive electrode voltage VBAT, the other end of the battery short-circuit point JV1 is connected to the positive electrode of the lithium battery BAT1, and the negative electrode of the lithium battery BAT1 is connected to the protection unit reference ground BGND.

[0008] Based on the above scheme, the resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, resistor R1, resistor R2, resistor R3, resistor R4 and resistor R5 are chip resistors, and the capacitors CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7 and capacitor C8 are chip capacitors.

[0009] Preferably, the model of the DC-DC chip UQ1 is MP2451DT.

[0010] Based on the above solution, the model of LDO chip UQ2 is MDS340-3-SOT89.

[0011] Based on the above solution, the model of the lithium battery charging chip U1 is SY6978ADC.

[0012] Based on the above solution, the model of the lithium battery protection chip U2 is SGM41100A.

[0013] The beneficial effects of the utility model are as follows: it has multiple battery protection functions such as overcharge protection, over-discharge protection, overcurrent protection, etc., which can effectively prevent battery damage or safety accidents; it has a wide voltage and current input range, which can adapt to lithium batteries of different brands and models; by accurately controlling the current and voltage during the charging process, it helps to extend the service life of the battery and increase the number of battery cycles; the battery power is monitored in real time, which can better manage the use of the battery and the charging action. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 : Circuit diagram of the power supply unit of the utility model;

[0015] Figure 2 : Circuit diagram of the lithium battery charging unit of the utility model;

[0016] Figure 3 : Schematic diagram of the connection between the electric energy meter, the power supply unit and the lithium battery charging unit of the utility model;

[0017] Figure 4 : Circuit diagram of the battery protection unit of the utility model. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0019] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] like Figures 1 to 4 As shown, a lithium battery intelligent charging system includes a power supply unit and a lithium battery charging unit;

[0021] The power supply unit includes capacitor CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, DC-DC chip UQ1, diode DQ11, inductor LQ1 and LD0 chip UQ2. The system input voltage MHVDD is connected to the 5-pin VIN port of the DC-DC chip UQ1, and one end of the resistor RQ1 is connected to On the system input voltage MHVDD, the other end and one end of the resistor RQ2 are connected to the EN port of the DC-DC chip UQ14 pin. The other end of the resistor RQ2 and the 2-pin GND port of the DC-DC chip UQ1 are connected to the system reference ground GND. The capacitors CQ4, CQ5, and CQ6 are connected in parallel between the system input voltage MHVDD and the system reference ground GND. The capacitor CQ1 is connected in parallel between the 6-pin SW port and the 1-pin BST port of the DC-DC chip UQ1. At the same time, the SW port is connected to The cathode of diode DQ11 and one end of inductor LQ1, the anode of diode DQ11 is connected to the system reference ground GND, the other end of inductor LQ1 is connected to the lithium battery charging voltage B+5V, capacitors CQ2, CQ3, CQ8 and CQ10 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, one end of resistor RQ5 is connected to the lithium battery charging voltage B+5V, and the other end is connected to one end of resistor RQ4, and the other end of resistor RQ4 and one end of resistor RQ3 are connected to D On the 3-pin FB port of the C-DC chip UQ1, the other end of the resistor RQ3 is connected to the system reference ground GND, the 2-pin VIN port of the LDO chip UQ2 is connected to the lithium battery charging voltage B+5V, the 1-pin GND port of the LDO chip UQ2 is connected to the system reference ground GND, the 3-pin VOUT port of the LDO chip UQ2 is connected to the lithium battery charging unit working voltage DVDD, and the capacitors CQ7 and CQ9 are connected in parallel between the lithium battery charging unit working voltage DVDD and the system reference ground GND;

[0022] The lithium battery charging unit includes capacitor C1, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, resistor R1, resistor R3, resistor R4, resistor R5 and lithium battery charging chip U1. Capacitor C3 and capacitor C4 are connected in parallel between the 2-pin GND port and the 3-pin OUT port of the lithium battery charging chip U1. The 2-pin GND port is connected to the system reference ground GND, and the 3-pin OUT port is connected to the lithium battery positive electrode voltage VBAT. One end of the chip resistor R4 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the lithium battery voltage sampling signal Battery_ADC. After the resistor R5 and capacitor C8 are connected in parallel, one end is connected to the battery voltage sampling signal Battery_ADC. The other end is connected to the system reference ground GND, capacitor C1 is connected in parallel between the 6-pin CHGB port of the lithium battery charging chip U1 and the system reference ground GND, the 6-pin CHGB port of the chip U1 is connected to the charging status signal CHGB, the chip resistor R1 is connected in series between the charging status signal CHGB and the lithium battery charging unit working voltage DVDD, the 5-pin IN port of the lithium battery charging chip U1 is connected to the lithium battery charging voltage B+5V, capacitor C6 and capacitor C7 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, the 4-pin PWM port of the lithium battery charging chip U1 is connected to the adjustment signal PWM, and resistor R3 and capacitor C5 are connected in parallel between the adjustment signal PWM and the system reference ground GND.

[0023] It also includes a lithium battery protection unit, which includes a resistor R2, a capacitor C2, a battery short-circuit point JV1, a rechargeable lithium battery BAT1 and a lithium battery protection chip U2, one end of the resistor R2 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the 1-pin PCKP port of the lithium battery protection chip U2, the 2-pin, 3-pin and 7-pin PCKN ports of the lithium battery protection chip U2 are connected to the system reference ground GND, the capacitor C2 is connected in parallel between the protection unit reference ground BGND and the 6-pin BYPS port of the lithium battery protection chip U2, the 4-pin and 5-pin BATN ports of the lithium battery protection chip U2 are connected to the protection unit reference ground BGND, one end of the battery short-circuit point JV1 is connected to the lithium battery positive electrode voltage VBAT, the other end of the battery short-circuit point JV1 is connected to the positive electrode of the lithium battery BAT1, and the negative electrode of the lithium battery BAT1 is connected to the protection unit reference ground BGND.

[0024] The energy meter system is connected to the charging status signal CHGB, the regulation signal PWM and the battery voltage sampling signal Battery_ADC. The power supply unit uses a DC-DC circuit and an LDO circuit to power the system. The charging status signal CHGB in the lithium battery charging unit is at a low level when the battery is charging and at a high level when the battery is fully charged. After detecting that the charging status signal CHGB is low, the energy meter system controls the charging current of the charging unit by controlling the output regulation signal PWM frequency. When the charging status signal CHGB becomes high, the energy meter system turns off the regulation signal PWM output to achieve overcharge protection of the battery. At the same time, the energy meter system detects the battery voltage sampling signal Battery_ADC to achieve real-time monitoring of the lithium battery voltage. When the battery in the lithium battery protection unit is in a deep discharge state, the battery protection chip U2 can intelligently disconnect the battery pack to avoid further damage or danger to the battery and achieve over-discharge protection.

[0025] Preferably, the resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, resistor R1, resistor R2, resistor R3, resistor R4 and resistor R5 are chip resistors, and the capacitors CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7 and capacitor C8 are chip capacitors, thereby reducing the volume of components.

[0026] Optionally, the model of the DC-DC chip UQ1 is MP2451DT, the model of the LDO chip UQ2 is MDS340-3-SOT89, the model of the lithium battery charging chip U1 is SY6978ADC, and the model of the lithium battery protection chip U2 is SGM41100A.

[0027] The present invention is described above by way of examples, but the present invention is not limited to the above specific embodiments, and any changes or modifications based on the present invention belong to the scope of protection required by the present invention.

Claims

1. A lithium battery intelligent charging system, characterized in that: It includes a power supply unit and a lithium battery charging unit, wherein the power supply unit adopts an LDO circuit; The lithium battery charging unit includes capacitor C1, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, capacitor C8, resistor R1, resistor R3, resistor R4, resistor R5 and lithium battery charging chip U1. Capacitor C3 and capacitor C4 are connected in parallel between the 2-pin GND port and the 3-pin OUT port of the lithium battery charging chip U1. The 2-pin GND port is connected to the system reference ground GND, and the 3-pin OUT port is connected to the lithium battery positive electrode voltage VBAT. One end of the chip resistor R4 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the lithium battery voltage sampling signal Battery_ADC. After the resistor R5 and capacitor C8 are connected in parallel, one end is connected to the battery voltage sampling signal Battery_ADC. The other end is connected to the system reference ground GND, capacitor C1 is connected in parallel between the 6-pin CHGB port of the lithium battery charging chip U1 and the system reference ground GND, the 6-pin CHGB port of the chip U1 is connected to the charging status signal CHGB, the chip resistor R1 is connected in series between the charging status signal CHGB and the lithium battery charging unit working voltage DVDD, the 5-pin IN port of the lithium battery charging chip U1 is connected to the lithium battery charging voltage B+5V, capacitor C6 and capacitor C7 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, the 4-pin PWM port of the lithium battery charging chip U1 is connected to the adjustment signal PWM, and resistor R3 and capacitor C5 are connected in parallel between the adjustment signal PWM and the system reference ground GND.

2. A lithium battery intelligent charging system according to claim 1, characterized in that: The power supply unit includes capacitor CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, DC-DC chip UQ1, diode DQ11, inductor LQ1 and LD0 chip UQ2. The system input voltage MHVDD is connected to the 5-pin VIN port of the DC-DC chip UQ1, and one end of the resistor RQ1 is connected to On the system input voltage MHVDD, the other end and one end of the resistor RQ2 are connected to the EN port of the DC-DC chip UQ14 pin. The other end of the resistor RQ2 and the 2-pin GND port of the DC-DC chip UQ1 are connected to the system reference ground GND. The capacitors CQ4, CQ5, and CQ6 are connected in parallel between the system input voltage MHVDD and the system reference ground GND. The capacitor CQ1 is connected in parallel between the 6-pin SW port and the 1-pin BST port of the DC-DC chip UQ1. At the same time, the SW port is connected to The cathode of diode DQ11 and one end of inductor LQ1, the anode of diode DQ11 is connected to the system reference ground GND, the other end of inductor LQ1 is connected to the lithium battery charging voltage B+5V, capacitors CQ2, CQ3, CQ8 and CQ10 are connected in parallel between the lithium battery charging voltage B+5V and the system reference ground GND, one end of resistor RQ5 is connected to the lithium battery charging voltage B+5V, and the other end is connected to one end of resistor RQ4, and the other end of resistor RQ4 and one end of resistor RQ3 are connected to D On the 3-pin FB port of the C-DC chip UQ1, the other end of the resistor RQ3 is connected to the system reference ground GND, the 2-pin VIN port of the LDO chip UQ2 is connected to the lithium battery charging voltage B+5V, the 1-pin GND port of the LDO chip UQ2 is connected to the system reference ground GND, the 3-pin VOUT port of the LDO chip UQ2 is connected to the lithium battery charging unit working voltage DVDD, and the capacitors CQ7 and CQ9 are connected in parallel between the lithium battery charging unit working voltage DVDD and the system reference ground GND.

3. A lithium battery intelligent charging system according to claim 1, characterized in that: It also includes a lithium battery protection unit, which includes a resistor R2, a capacitor C2, a battery short-circuit point JV1, a rechargeable lithium battery BAT1 and a lithium battery protection chip U2, one end of the resistor R2 is connected to the lithium battery positive electrode voltage VBAT, and the other end is connected to the 1-pin PCKP port of the lithium battery protection chip U2, the 2-pin, 3-pin and 7-pin PCKN ports of the lithium battery protection chip U2 are connected to the system reference ground GND, the capacitor C2 is connected in parallel between the protection unit reference ground BGND and the 6-pin BYPS port of the lithium battery protection chip U2, the 4-pin and 5-pin BATN ports of the lithium battery protection chip U2 are connected to the protection unit reference ground BGND, one end of the battery short-circuit point JV1 is connected to the lithium battery positive electrode voltage VBAT, the other end of the battery short-circuit point JV1 is connected to the positive electrode of the lithium battery BAT1, and the negative electrode of the lithium battery BAT1 is connected to the protection unit reference ground BGND.

4. A lithium battery intelligent charging system according to claim 3, characterized in that: The resistor RQ1, resistor RQ2, resistor RQ3, resistor RQ4, resistor RQ5, resistor R1, resistor R2, resistor R3, resistor R4 and resistor R5 are chip resistors, and the capacitors CQ1, capacitor CQ2, capacitor CQ3, capacitor CQ4, capacitor CQ5, capacitor CQ6, capacitor CQ7, capacitor CQ8, capacitor CQ9, capacitor CQ10, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7 and capacitor C8 are chip capacitors.

5. A lithium battery intelligent charging system according to claim 1, characterized in that: The model of the DC-DC chip UQ1 is MP2451DT.

6. A lithium battery intelligent charging system according to claim 1, characterized in that: The model of LDO chip UQ2 is MDS340-3-SOT89.

7. A lithium battery intelligent charging system according to claim 1, characterized in that: The model of the lithium battery charging chip U1 is SY6978ADC.

8. A lithium battery intelligent charging system according to claim 2, characterized in that: The model of the lithium battery protection chip U2 is SGM41100A.

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