CN107979137A - A kind of Li-Battery monitor circuit - Google Patents

Abstract

The invention discloses a lithium battery monitoring circuit, which includes a voltage detection module, a battery switching module, and a charging and discharging module. The input end of the voltage detection module is connected to a power supply, and the input end of the voltage detection module is connected to a processor of a current monitoring circuit. , the input end of the battery switching module is connected to a power supply, the input end of the current monitoring circuit and the input end of the charging and discharging module are both connected to the output end of the battery switching module, and the input end of the charging and discharging module is connected to a power supply; The present invention detects the current and voltage and protects the circuit during the charging and discharging process of the lithium battery in daily use, thereby reducing the damage to the lithium battery caused by excessive use in the use process, achieving the purpose of reducing power consumption and prolonging the service life of the lithium battery .

Description

A lithium battery monitoring circuit

technical field

The invention relates to the technical field of lithium batteries, in particular to a lithium battery monitoring circuit.

Background technique

Due to its high working voltage, small size, light weight, high energy, no memory effect, no pollution, small self-discharge, and long cycle life, lithium-ion batteries are ideal energy sources for development in the 21st century.

Lithium-ion batteries are currently divided into two categories: liquid lithium-ion batteries (LIB) and polymer lithium-ion batteries (PLB). Among them, the liquid lithium-ion battery refers to the secondary battery in which the Li + intercalation compound is the positive and negative electrodes. At present, lithium-ion batteries are widely used in mobile phones, notebook computers, power tools, electric vehicles, street lamp backup power, navigation lights, and small household appliances. It can be said that they are the largest application group. The use of discharge and high-frequency charging will cause some safety hazards and shortened battery life after long-term use.

Therefore, there are defects and deficiencies in the prior art and need to be improved.

Contents of the invention

In view of this, the present invention proposes a lithium battery monitoring circuit, which mainly performs current and voltage detection and circuit protection on the charging and discharging process of the lithium battery in daily use, and reduces the damage to the lithium battery caused by excessive use during use. , to reduce power consumption and prolong the service life of the lithium battery.

Technical scheme of the present invention is as follows:

A lithium battery monitoring circuit, comprising a voltage detection module, a battery switching module, and a charging and discharging module, the input end of the voltage detection module is connected to a power supply, the input end of the voltage detection module is connected to a processor of a current monitoring circuit, and the battery The input end of the switching module is connected to the power supply, the input end of the current monitoring circuit and the input end of the charging and discharging module are both connected to the output end of the battery switching module, and the output end of the charging and discharging module is connected to the power supply;

The voltage detection module includes a three-terminal voltage stabilizing circuit, a voltage dividing circuit and a comparison circuit, the input end of the three-terminal voltage stabilizing circuit is connected to the positive pole of the power supply, the voltage dividing circuit is electrically connected to the comparison circuit, and the comparison circuit The input terminal is connected to the positive pole of the power supply;

The battery switching module is provided with a drive circuit and a relay, and the output end of the drive circuit is connected to the input end of the relay;

The charging and discharging module is provided with a charging circuit and a discharging circuit, the input end of the charging circuit and the input end of the discharging circuit are connected to the output end of the battery switching module, the charging circuit and the discharging circuit The output terminals are all connected to the positive pole of the battery.

Further, the drive circuit includes an inverter 74LS04 and a transistor S9013, which are controlled by the control signal output from the P1 port to control the on and off states of the relay; the inverter 74LS04 is connected in series with the transistor S9013 through a resistor R1.

Further, the relay adopts a double-contact relay 4137 capable of converting two signals at the same time, and controls and switches the charging and discharging circuit and the battery state detection circuit at the same time.

Further, the three-terminal voltage stabilizing circuit is provided with a voltage stabilizing block LM317, and the comparing circuit is provided with an integrated block LM339.

Further, the charging circuit is provided with an inverter 74LS04, a triode S9013, a triode S9012 and a triode TIP31C, the inverter 74LS04 is connected in series with the triode S9013 via a resistor R1, and the triode S9013 is connected to the triode S9012 via a resistor R2. In series, the triode S9012 is connected in parallel with the triode TIP31C, and the triode TIP31C is connected to the positive electrode of the battery through a resistor R3.

Further, the discharge circuit is provided with an inverter 74LS04, a triode S9013, a triode 2SD882 and a triode, the inverter 74LS04 is connected in series with the triode S9013 via a resistor R5, and the triode S9013 is connected in series with the triode 2SD882 via a resistor R6 , the triode 2SD882 is connected to the positive pole of the battery through the resistor R4.

Beneficial effects: compared with the prior art, the present invention reduces the damage to the lithium battery caused by excessive use in the use process by performing current and voltage detection and circuit protection during the charging and discharging process of the lithium battery in daily use, and achieves a reduction in power consumption. Consumption, the purpose of prolonging the service life of the lithium battery.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only for invention For some embodiments, those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is the schematic diagram of the battery switching unit circuit of the lithium battery monitoring circuit of the present invention;

Fig. 2 is the schematic diagram of the battery charging and discharging circuit of the lithium battery monitoring circuit of the present invention;

FIG. 3 is a schematic diagram of the battery voltage detection circuit of the lithium battery monitoring circuit of the present invention.

Detailed ways

In order to facilitate the understanding of the present invention, the present invention will be described in more detail below in conjunction with the accompanying drawings and specific embodiments. Preferred embodiments of the invention are shown in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

As shown in Figure 1, a lithium battery monitoring circuit includes a voltage detection module, a battery switching module, and a charging and discharging module. The input end of the voltage detection module is connected to a power supply, and the input end of the voltage detection module is connected to the current monitoring circuit. processor, the input end of the battery switching module is connected to a power supply, the input end of the current monitoring circuit and the input end of the charging and discharging module are connected to the output end of the battery switching module, and the output end of the charging and discharging module is connected to power supply;

A voltage detection module, the voltage detection module includes a three-terminal voltage regulator circuit, a voltage divider circuit and a comparison circuit, the input terminal of the three-terminal voltage regulator circuit is connected to the positive pole of the power supply, and the voltage divider circuit is electrically connected to the comparison circuit, The input terminal of the comparison circuit is connected to the positive pole of the power supply;

A battery switch module, the battery switch module is provided with a drive circuit and a relay, the output end of the drive circuit is connected to the input end of the relay;

A charging and discharging module, the charging and discharging module is provided with a charging circuit and a discharging circuit, the input terminals of the charging circuit and the discharging circuit are connected to the output terminal of the battery switching module, the charging circuit and the discharging circuit The output terminals of the circuit are all connected to the positive pole of the battery.

Further, the drive circuit includes an inverter 74LS04 and a transistor S9013, and the drive circuit is controlled by the control signal output from the P1 port to control the on and off states of the relay.

Further, the relay adopts a double-contact relay 4137 capable of converting two signals at the same time, and controls the switching of the charging and discharging circuit and the battery state detection circuit at the same time.

Further, the three-terminal voltage stabilizing circuit is provided with a voltage stabilizing block LM317, and the comparing circuit is provided with an integrated block LM339.

Further, the charging circuit is provided with an inverter 74LS04, a transistor S9013 and a transistor S9012, and the inverter 74LS04, the transistor S9013 and the transistor S9012 are connected in series.

Further, the discharge circuit is provided with an inverter 74LS04, a transistor S9013 and a transistor 2SD882, and the inverter 74LS04, the transistor S9013 and the transistor 2SD882 are connected in series.

As shown in Figure 1, the battery switching module is composed of a switching circuit array composed of a driving circuit and a relay. Wherein, each switching circuit unit corresponds to a battery cell. Using the interrupt control function of the external interrupt INT1, and through the P3.6 of the single-chip microcomputer to detect and judge the state of the two switching buttons, and send the control signal to the drive circuit composed of the inverter 74LS04 and the transistor S9013, the drive circuit control can be switched simultaneously The double-contact relay 4137 with two signals realizes simultaneous switching of the charging and discharging circuit and the battery state detection circuit; the interrupt control function of the external interrupt INT1 is used to detect and judge the state of the two switching buttons through P3.6 of the single-chip microcomputer, and at the same time Use the "Move Up" and "Move Down" buttons to manually switch between battery cells.

As shown in Figure 2, the charging and discharging module is composed of a charging circuit, a discharging circuit and a charging and discharging control circuit. The charging or discharging control signal output by the single-chip microcomputer, through controlling the inverter 74LS04, the triode S9013 and the voltage dividing resistor in the charging or discharging circuit, realizes charging or discharging the battery.

As shown in Figure 3, the voltage detection module consists of a three-terminal voltage regulator circuit, a voltage divider circuit and a comparison circuit. The three-terminal voltage regulator circuit is composed of LM317 and its peripheral circuits. The output voltage is divided by the voltage divider circuit and used as a reference voltage, which is sent to one end of the comparator composed of LM339, and the voltage collected from the positive pole of the battery is sent to the comparator. The other end of the comparator circuit, from the level state of the output of each comparator, the current battery power condition and placement status can be judged. These state signals are used as detection signals, and then sent back to the single-chip microcomputer, which controls the charging and discharging circuit to work and indicates the state of the battery.

The present invention detects the current and voltage and protects the circuit during the charging and discharging process of the lithium battery in daily use, thereby reducing the damage to the lithium battery caused by overuse in the use process, having higher stability, reducing power consumption, and prolonging the battery life of the lithium battery. purpose of service life.

It should be noted that the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope of the description of the present invention; and, for those of ordinary skill in the art, improvements can be made according to the above description Or transformation, and all these improvements and transformations should belong to the protection scope of the appended claims of the present invention.

Claims (6)

1. a kind of Li-Battery monitor circuit, including current monitoring circuit, it is characterised in that further include：Voltage detection module, battery Handover module, charge-discharge modules, the input terminal connection power supply of the voltage detection module, the input terminal of the voltage detection module Connect the processor of current monitoring circuit, the input terminal connection power supply of the battery handover module, the input of current monitoring circuit Output terminal of the input terminal with the battery handover module of end and the charge-discharge modules is connected, the charge-discharge modules it is defeated Outlet connects power supply；

The voltage detection module includes three-terminal voltage-stabilizing circuit, bleeder circuit and comparison circuit, the three-terminal voltage-stabilizing circuit it is defeated Enter end connection positive pole, the bleeder circuit is electrically connected with the comparison circuit, the input terminal connection electricity of the comparison circuit Source cathode；

The battery handover module is equipped with drive circuit and relay, and the output terminal of the drive circuit is defeated with the relay Enter end to be connected；

The charge-discharge modules are equipped with charging circuit and discharge circuit, the input terminal of the charging circuit and the discharge circuit Output terminal of the input terminal with the battery handover module is connected, and the output terminal of the charging circuit and the discharge circuit is equal It is connected with the cathode of battery.

2. a kind of Li-Battery monitor circuit according to claim 1, it is characterised in that the drive circuit includes reverser 74LS04 and triode S9013, the control signal by P1 mouthfuls of output control, the open and close state of relay are controlled；Institute Reverser 74LS04 is stated to connect with the triode S9013 through resistance R1.

3. a kind of Li-Battery monitor circuit according to claim 1, it is characterised in that the relay, which uses, to be had at the same time Double electric shock relays 4137 of two paths of signals are changed, control is carried out at the same time to charging and discharging circuit and battery status measure loop and is cut Change.

4. a kind of Li-Battery monitor circuit according to claim 1, it is characterised in that the three-terminal voltage-stabilizing circuit is equipped with steady Briquetting LM317, the comparison circuit are equipped with integrated package LM339.

5. a kind of Li-Battery monitor circuit according to claim 1, it is characterised in that the charging circuit is equipped with phase inverter 74LS04, triode S9013, triode S9012 and triode TIP31C, the phase inverter 74LS04 is through resistance R1 and described three Pole pipe S9013 connects, and the triode S9013 connects through resistance R2 with the triode S9012, the triode S9012 and The triode TIP31C is in parallel, and the triode TIP31C is through resistance R3 connection anodes.

6. a kind of Li-Battery monitor circuit according to claim 1, it is characterised in that the discharge circuit is equipped with phase inverter 74LS04, triode S9013, triode 2SD882 and triode, the phase inverter 74LS04 is through resistance R5 and the triode S9013 series connection, the triode S9013 connect through resistance R6 with the triode 2SD882, and the triode 2SD882 is through electricity Hinder R4 connection anodes.