Safety protection circuit of split type battery

Abstract

The utility model relates to the technical field of split batteries, and discloses a safety protection circuit of a split battery, which monitors key parameters such as voltage, current, temperature and the like of the battery and performs charging and discharging control according to the parameters so as to prevent abnormal conditions such as over-charging, over-discharging, overheating and the like of the battery. The safety of the battery is obviously improved, the service life of the battery is prolonged, and the charge-discharge efficiency of the battery is optimized; when the charging voltage of the battery exceeds a set value, a charging loop is automatically cut off, so that the battery is prevented from being damaged due to overcharge and even safety accidents such as fire or explosion are prevented; the temperature of the battery can be monitored in real time, and when the temperature exceeds a set value, the temperature protection circuit can take a measure of cutting off a charging or discharging loop so as to prevent the battery from being overheated; and the battery management circuit monitors the residual electric quantity of the battery in real time, provides data for the battery management circuit, and is used for estimating the residual use time of the battery, controlling the charging and discharging processes and helping a user to arrange the use and charging plans of the battery.

Description

TECHNICAL FIELD

[0001] The utility model relates to split type battery technical field, concretely is a split type battery's safety protection circuit. BACKGROUND

[0002] Split type battery is a kind of battery and the design of separation of electric appliance or equipment, this design allows the replaceability of battery, to bring many advantages and flexibility.

[0003] Through the retrieval, the patent of application No. CN201620545910.2 discloses a kind of split type battery constant voltage power supply circuit, including battery, charging circuit and discharging circuit, also include main control unit MCU, charge-discharge protection circuit, the charge-discharge protection circuit includes discharge protection circuit and charge-discharge temperature protection circuit;The discharging circuit is constant voltage discharging circuit, the charging circuit and constant voltage discharging circuit and main control unit MCU circuit circuit connection;The charge-discharge temperature protection circuit is equipped with temperature sensor of detecting battery temperature, the charge-discharge temperature protection circuit is connected with main control unit MCU circuit.Beneficial effect lies in: it is realized under the condition of not influencing portable host product overall appearance, prolongs the endurance time of product.Simultaneously with battery constant voltage output, solve the problem that line loss gradually becomes big with battery voltage reduction under long-distance power supply condition, improve the actual output capacity of battery.

[0004] Current split type battery is not convenient for monitoring the current, voltage, temperature and other parameters of battery, cannot be charged and discharged according to the parameter change of battery, prone to abnormal condition of battery, reduce battery life;And not convenient for real-time monitoring the power of battery, not convenient for controlling the charging and discharging process, cannot help user arrange the use and charging plan of battery, therefore we need to propose a kind of split type battery's safety protection circuit. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a kind of split type battery's safety protection circuit, by the design of battery management circuit, monitor the voltage, current, temperature and other key parameters of battery, and according to these parameters, charge and discharge control is carried out, to prevent the occurrence of battery overcharge, overdischarge, overheat and other abnormal conditions, significantly improve the safety of battery, prolong the service life of battery, and optimize the charge-discharge efficiency of battery;By the design of overcharge protection circuit, when battery charging voltage exceeds set value, automatically cut off charging loop, prevent battery from being damaged due to overcharge, even cause fire or explosion and other safety accidents;By the design of overdischarge protection circuit, when battery discharge voltage is lower than set value, overdischarge protection circuit will cut off discharge loop, prevent battery from overdischarge, avoid battery from being exhausted due to excessive discharge, thereby prolong the service life of battery, to solve the problems raised in the above background.

[0006] To achieve the above object, the utility model provides following technical scheme: a safety protection circuit of split type battery, include:

[0007] Battery management circuit responsible for monitoring battery voltage, current, temperature parameter and realizing charge and discharge control;

[0008] When battery charging voltage exceeds set value, overcharge protection circuit that disconnects charging loop;

[0009] When battery discharge voltage is lower than set value, overdischarge protection circuit that disconnects discharge loop;

[0010] When battery short circuit occurs, short circuit protection circuit that disconnects battery loop;

[0011] When battery temperature exceeds set value, temperature protection circuit that disconnects charge / discharge loop;

[0012] Battery capacity detection circuit that can display battery capacity state in real time and find battery performance decline in time;

[0013] Overcharge protection circuit, overdischarge protection circuit, short circuit protection circuit, temperature protection circuit, battery capacity detection circuit are electrically connected with battery management circuit.

[0014] Preferably, the battery management circuit includes chip U1, the 1 pin of chip U1 is connected with parallelly arranged capacitor C1 and diode D5, the 2 pin of chip U1 is connected with diode D4 and inductor L1 respectively, the 3 pin of chip U1 is connected with capacitor C3 and diode D1, one end of diode D1 is connected with magnetic bead L2, series resistance R2 and resistance R3, parallel capacitor C4 and capacitor C5, the 6 pin of chip U1 is connected on the wiring terminal of resistance R2 and resistance R3, the 7 pin of chip U1 is connected with resistance R4 and magnetic bead L3 respectively, the magnetic bead L3 and magnetic bead L2 are connected with parallelly arranged battery BT1 and capacitor C2.

[0015] Preferably, the overcharge protection circuit includes chip U2 and chip U3, the 1 pin of chip U2 is connected with the 2 pin of chip U3, the 1 pin of chip U2 is connected with capacitor C10, the 3 pin of chip U2 is connected with resistance R41, the 5 pin of chip U2 is connected with capacitor C20;

[0016] The 3-pin of the chip U3 is connected with the light emitting diode D11 and the resistor R11 in series, the 4-pin of the chip U3 is connected with the light emitting diode D12 and the resistor R21 in series, the resistor R11 and the resistor R21 are both connected to the 2-pin of the chip U3, the 1-pin of the chip U3 is further connected with the grounded capacitor C40, the 8-pin of the chip U3 is connected with the inductor L11 and the resistor R31, one end of the resistor R31 is connected with the capacitor C30 and the battery BT1 arranged in parallel.

[0017] Preferably, the over-discharge protection circuit comprises the amplifier U1A, the amplifier U1B, the MOS tube Q13, the MOS tube Q23, the MOS tube Q33, the triode Q43, the 8-pin of the amplifier U1A is connected with the source of the MOS tube Q13 and the drain of the MOS tube Q23 respectively, the 1-pin of the amplifier U1A is connected with the base of the triode Q43 through the resistor R83, the emitter of the triode Q43 is connected with the source of the MOS tube Q23 through the resistor RL, and the 1-pin of the amplifier U1A is connected with the gate of the MOS tube Q33.

[0018] Preferably, the short-circuit protection circuit comprises the MOS tube Q120 and the triode Q130, the source of the MOS tube Q120 is connected with the emitter of the triode Q130, the gate of the MOS tube Q120 is connected with the connection end of the collector of the triode Q130 through the resistor R27, and the drain of the MOS tube Q120 is connected with the base of the triode Q130 through the resistor R28.

[0019] Preferably, the temperature protection circuit comprises the chip U24, the 1-pin of the chip U24 is connected with the capacitor C51, the 1-pin and the 3-pin of the chip U24 are connected with the light emitting diode D51 and the resistor R51, the 7-pin and the 10-pin of the chip U24 are connected with the capacitor C52 and the battery BT1 arranged in parallel, and the 6-pin and the 7-pin of the chip U24 are connected with the resistor R52.

[0020] Preferably, the battery power detection circuit comprises the chip U5, the 1-pin and the 8-pin of the chip U5 are connected with the diode D17, the 1-pin of the chip U5 is connected with the capacitor C37, the capacitor C47 and the capacitor C57 arranged in parallel, the 6-pin and the 8-pin of the chip U5 are connected with the inductor L17, the 6-pin of the chip U5 is connected with the capacitor C67, the capacitor C77 and the capacitor C87 arranged in parallel, the 3-pin of the chip U5 is connected with the grounded resistor R37, the 2-pin and the 4-pin of the chip U5 are connected with the light emitting diode LED1 and the light emitting diode LED2, the 5-pin of the chip U5 is respectively connected with the resistor R17, the resistor R27, the capacitor C17 and the capacitor C27 arranged in parallel, and the connection end of the light emitting diode LED1 and the light emitting diode LED2 is connected with the resistor R27.

[0021] Compared with the prior art, the utility model has the advantages that:

[0022] 1、 the utility model discloses the design of battery management circuit, monitors the voltage, current, temperature and other key parameters of battery, and according to these parameters, charge and discharge control is carried out to prevent the occurrence of battery overcharge, overdischarge, overheat and other abnormal conditions, significantly improve the safety of battery, prolong the service life of battery, and optimize the charge-discharge efficiency of battery;

[0023] 2、 the utility model discloses the design of overcharge protection circuit, when battery charging voltage exceeds the set value, automatically cut off the charging circuit, prevent the damage of battery due to overcharge, even cause fire or explosion and other safety accidents; Through the design of overdischarge protection circuit, when the battery discharge voltage is lower than the set value, the overdischarge protection circuit will cut off the discharge circuit, prevent the overdischarge of battery, avoid the battery due to overdischarge and consume the stored electric energy, thereby prolonging the service life of battery;

[0024] 3、 the utility model discloses the design of temperature protection circuit, can monitor the temperature of battery in real time, when temperature exceeds the set value, temperature protection circuit will take the measure of cutting off the charging or discharging circuit to prevent the overheat of battery, prevent the fire or explosion and other safety accidents caused by the overheat of battery;

[0025] 4、 the utility model discloses the design of battery power detection circuit, can monitor the remaining power of battery in real time, and provides data to battery management circuit, is used for estimating the remaining use time of battery, control charging and discharging process, helps user to arrange the use and charging plan of battery. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is the circuit diagram of battery management circuit of the utility model;

[0027] Figure 2 It is the circuit diagram of overcharge protection circuit of the utility model;

[0028] Figure 3 It is the circuit diagram of overdischarge protection circuit of the utility model;

[0029] Figure 4 It is the circuit diagram of short-circuit protection circuit of the utility model;

[0030] Figure 5 It is the circuit diagram of temperature protection circuit of the utility model;

[0031] Figure 6 It is the circuit diagram of battery power detection circuit of the utility model. DETAILED DESCRIPTION

[0032] Clearly, the described embodiments are merely a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all the other embodiments obtained by the person skilled in the art without creative labor fall within the protection scope of the present utility model.

[0033] Please refer to Figures 1-6 The present utility model provides a technical scheme: a safety protection circuit of split type battery, which comprises:

[0034] The battery management circuit is responsible for monitoring battery voltage, current and temperature parameters and realizing charge and discharge control;

[0035] The battery management circuit comprises a chip U1, a capacitor C1 and a diode D5 connected in parallel are connected to the 1 pin of the chip U1, a diode D4 and an inductor L1 are respectively connected to the 2 pin of the chip U1, a capacitor C3 and a diode D1 are connected to the 3 pin of the chip U1, one end of the diode D1 is connected with a magnetic bead L2, a resistor R2 and a resistor R3 connected in series, a capacitor C4 and a capacitor C5 connected in parallel, the 6 pin of the chip U1 is connected to the wiring end of the resistor R2 and the resistor R3, the 7 pin of the chip U1 is respectively connected with a resistor R4 and a magnetic bead L3, and the magnetic bead L3 and the magnetic bead L2 are connected with a battery BT1 and a capacitor C2 connected in parallel.

[0036] The battery BT1 is connected to the circuit through the magnetic bead L2 and the magnetic bead L3, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C1 and the capacitor C5 are used for filtering processing, the diode D5 plays a voltage stabilizing role, the resistor R2 and the resistor R3 are used for voltage division, the diode D1 is used for rectification, the inductor L1 is used for filtering processing, the pins of the chip U1 comprise: VCC: power supply pin; GND: ground pin; PD: power supply detection pin; ND: noise detection pin; AD_I: analog input pin; AD_V: analog voltage pin; LED: LED drive pin; VREF: reference voltage pin; the diode D2 and the diode D3 are used for driving LED, and the resistor R1 and the resistor R5 play a current limiting role.

[0037] When the battery charging voltage exceeds the set value, the overcharge protection circuit of the charging circuit is cut off;

[0038] The overcharge protection circuit comprises a chip U2 and a chip U3, the 1 pin of the chip U2 is connected with the 2 pin of the chip U3, the 1 pin of the chip U2 is connected with a capacitor C10, the 3 pin of the chip U2 is connected with a resistor R41, and the 5 pin of the chip U2 is connected with a capacitor C20.

[0039] The 3-pin of the chip U3 is connected with the light emitting diode D11 and the resistor R11 in series, the 4-pin of the chip U3 is connected with the light emitting diode D12 and the resistor R21 in series, the resistor R11 and the resistor R21 are both connected to the 2-pin of the chip U3, the 1-pin of the chip U3 is further connected with the grounded capacitor C40, the 8-pin of the chip U3 is connected with the inductor L11 and the resistor R31, one end of the resistor R31 is connected with the capacitor C30 and the battery BT1 arranged in parallel.

[0040] The signal of the chip U2 is PW1515, the capacitor C10 is connected between VOUT and GND, the capacitor C20 is connected between VIN and GND, and the resistor R41 is connected between IADJ and GND for adjusting current.

[0041] The model of the chip U3 is PW4052, the pins of which are VIN, input voltage, BAT, battery connection pin, SW, switch pin, SEN, current detection pin, NC, non-connection pin, and PGND, power ground; the inductor L11 is connected between SW and SEN, the resistor R31 is connected between SEN and BAT for current detection; the capacitor C30 is connected between BAT and GND, the capacitor C40 is connected between VIN and GND, the diode D11 is connected between VIN and RED LED, and the diode D12 is connected between VIN and GREEN LED.

[0042] The constant current output is realized by the PW1515 chip, and the current is adjusted by the resistor R41. The battery charging function is realized by the PW4052 chip, and the current detection and control are realized by the inductor L11 and the resistor R31.

[0043] When the battery discharge voltage is lower than the set value, the over-discharge protection circuit of the discharge circuit is cut off.

[0044] The over-discharge protection circuit comprises an amplifier U1A, an amplifier U1B, MOS tubes Q13, Q23 and Q33, and a transistor Q43; the 8-pin of the amplifier U1A is connected with the source of the MOS tube Q13 and the drain of the MOS tube Q23 respectively; the 1-pin of the amplifier U1A is connected with the base of the transistor Q43 through the resistor R83; the emitter of the transistor Q43 is connected with the source of the MOS tube Q23 through the resistor RL; and the 1-pin of the amplifier U1A is connected with the gate of the MOS tube Q33.

[0045] A stable 2.5V voltage is provided by the voltage reference source DI3, and a voltage dividing network is formed by resistors R43, R13, R53, R23 and R33 to provide a reference voltage for the operational amplifier. The non-inverting input of the amplifier U1A is connected to the voltage reference network, and the inverting input of the amplifier U1A is connected to the voltage dividing point of resistors R73 and R93. The output of the amplifier U1A is connected to resistor R83 and the base of transistor Q43.

[0046] The base voltage of the transistor Q43 is controlled by the output of the amplifier U1A, and the collector of the transistor Q43 is connected to the load RL. The collector of the transistor Q43 is connected to the load RL, and the voltage of the power supply UBAT is provided by the MOS transistor Q13.

[0047] When the battery is short-circuited, the short-circuit protection circuit is turned off.

[0048] The short-circuit protection circuit includes MOS transistor Q120 and transistor Q130. The source of the MOS transistor Q120 is connected to the emitter of the transistor Q130. The gate of the MOS transistor Q120 is connected to the collector of the transistor Q130 through a resistor R27. The drain of the MOS transistor Q120 is connected to the base of the transistor Q130 through a resistor R28.

[0049] When the input voltage (Vin) is low: the gate voltage of the MOS transistor Q120 is low, and the output voltage Vout is high.

[0050] When the input voltage (Vin) is high: the base voltage of the transistor Q130 is high, and the transistor Q130 is turned on. The output voltage Vout is low.

[0051] When the battery temperature exceeds the set value, the temperature protection circuit is turned off to cut off the charging / discharging circuit.

[0052] The temperature protection circuit includes chip U24. A capacitor C51 is connected to pin 1 of the chip U24. A light-emitting diode D51 and a resistor R51 are connected between pin 1 and pin 3 of the chip U24. A capacitor C52 and a battery BT1 are connected in parallel between pin 7 and pin 10 of the chip U24. A resistor R52 is connected between pin 6 and pin 7 of the chip U24.

[0053] The capacitor C51 is used for filtering, the diode D51 is used for preventing reverse current, and the resistor R51 is used for limiting current. Pin 6 (ISET) of the chip U24 is a current setting pin, and the charging current is set by the resistor R52. The capacitor C52 is a battery capacitor used for filtering, and the resistor R52 is a current setting resistor connected to the ISET pin for setting the charging current.

[0054] The input voltage is filtered through C51, then connected to the VIN pin through the D51 diode to prevent reverse current, the LP28011 chip sets the charging current through the ISET pin, and outputs the current to the battery through the BATT pin, and the battery voltage is filtered through C52 and connected to the VBAT, and the STAT1 and STAT2 pins are used to indicate the charging state.

[0055] The battery capacity detection circuit can display the battery capacity state in real time and find the battery performance decline in time.

[0056] The battery capacity detection circuit comprises a chip U5, a diode D17 is connected between the 1st pin and the 8th pin of the chip U5, and the 1st pin of the chip U5 is connected with a capacitor C37, a capacitor C47 and a capacitor C57 which are arranged in parallel, an inductor L17 is connected between the 6th pin and the 8th pin of the chip U5, the 6th pin of the chip U5 is connected with a capacitor C67, a capacitor C77 and a capacitor C87 which are arranged in parallel, the 3rd pin of the chip U5 is connected with a ground resistor R37, the 2nd pin and the 4th pin of the chip U5 are connected with a light-emitting diode LED1 and a light-emitting diode LED2, and the 5th pin of the chip U5 is respectively connected with a resistor R17, a resistor R27, a capacitor C17 and a capacitor C27 which are arranged in parallel, and the connecting end of the light-emitting diode LED1 and the light-emitting diode LED2 is connected with the resistor R27.

[0057] A 5V input voltage is filtered through the resistor R17 and the capacitor C17, and further filtered through the resistor R27 and the capacitor C27, the CHRG pin of the chip U5 is connected to the red terminal of the LED1 to indicate the charging state, the STDBY pin is connected to the green terminal of the LED1 to indicate the standby state, and the PROG pin is connected to the ground through the resistor R37 (1.1KΩ) to set the charging current.

[0058] The diode D17 is used for preventing reverse current, and the inductor L17 is used for filtering to a stable current.

[0059] The overcharge protection circuit, the overdischarge protection circuit, the short-circuit protection circuit, the temperature protection circuit and the battery capacity detection circuit are electrically connected with the battery management circuit.

[0060] Although the embodiments of the present application have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A safety protection circuit for a split-type battery, characterized in that, include: Battery management circuit responsible for monitoring battery voltage, current, and temperature parameters and controlling charging and discharging; When the battery charging voltage exceeds the set value, the overcharge protection circuit of the charging circuit is cut off. When the battery discharge voltage is lower than the set value, the over-discharge protection circuit of the discharge circuit is cut off. When a short circuit occurs in the battery, the short circuit protection circuit of the battery circuit is disconnected. The temperature protection circuit of the charging / discharging circuit will be cut off when the battery temperature exceeds the set value. The temperature protection circuit includes a chip U24. A capacitor C51 is connected to pin 1 of the chip U24. A light-emitting diode D51 and a resistor R51 are connected between pins 1 and 3 of the chip U24. A capacitor C52 and a battery BT1 are connected in parallel between pins 7 and 10 of the chip U24. A resistor R52 is connected between pins 6 and 7 of the chip U24. A battery power detection circuit that can display the battery power status in real time and promptly detect battery performance degradation. The battery power detection circuit includes a chip U5. A diode D17 is connected between pins 1 and 8 of the chip U5. A capacitor C37, a capacitor C47, and a capacitor C57 are connected in parallel to pin 1 of the chip U5. An inductor L17 is connected between pins 6 and 8 of the chip U5. A capacitor C67, a capacitor C7, and a capacitor C87 are connected in parallel to pin 6 of the chip U5. A grounded resistor R37 is connected to pin 3 of the chip U5. LEDs LED1 and LED2 are connected between pins 2 and 4 of the chip U5. Resistors R17 and R27, and capacitors C17 and C27 are connected in parallel to pin 5 of the chip U5. The terminals of LEDs LED1 and LED2 are connected to resistor R27. The overcharge protection circuit, over-discharge protection circuit, short circuit protection circuit, temperature protection circuit, and battery power detection circuit are all electrically connected to the battery management circuit.

2. The safety protection circuit for a split-type battery according to claim 1, characterized in that: The battery management circuit includes a chip U1. A capacitor C1 and a diode D5 are connected in parallel to pin 1 of the chip U1. A diode D4 and an inductor L1 are connected to pin 2 of the chip U1. A capacitor C3 and a diode D1 are connected to pin 3 of the chip U1. One end of the diode D1 is connected to a ferrite bead L2, a series resistor R2 and a resistor R3, and a parallel capacitor C4 and a capacitor C5. Pin 6 of the chip U1 is connected to the terminals of resistors R2 and R3. Pin 7 of the chip U1 is connected to a resistor R4 and a ferrite bead L3. A battery BT1 and a capacitor C2 are connected in parallel between ferrite bead L3 and ferrite bead L2.

3. The safety protection circuit for a split-type battery according to claim 1, characterized in that: The overcharge protection circuit includes chip U2 and chip U3. Pin 1 of chip U2 is connected to pin 2 of chip U3. A capacitor C10 is connected to pin 1 of chip U2. A resistor R41 is connected to pin 3 of chip U2. A capacitor C20 is connected to pin 5 of chip U2. A light-emitting diode D11 and a resistor R11 are connected in series on pin 3 of chip U3. A light-emitting diode D12 and a resistor R21 are connected in series on pin 4 of chip U3. Both resistors R11 and R21 are connected to pin 2 of chip U3. A grounded capacitor C40 is also connected to pin 1 of chip U3. An inductor L11 and a resistor R31 are connected to pin 8 of chip U3. One end of the resistor R31 is connected to a capacitor C30 and a battery BT1 connected in parallel.

4. The safety protection circuit for a split-type battery according to claim 1, characterized in that: The over-discharge protection circuit includes amplifier U1A, amplifier U1B, MOSFET Q13, MOSFET Q23, MOSFET Q33, and transistor Q43. Pin 8 of amplifier U1A is connected to the source of MOSFET Q13 and the drain of MOSFET Q23, respectively. A resistor R83 is connected between pin 1 of amplifier U1A and the base of transistor Q43. A resistor RL is connected between the emitter of transistor Q43 and the source of MOSFET Q23. Pin 1 of amplifier U1A is connected to the gate of MOSFET Q33.

5. The safety protection circuit for a split-type battery according to claim 1, characterized in that: The short-circuit protection circuit includes a MOSFET Q120 and a transistor Q130. The source of the MOSFET Q120 is connected to the emitter of the transistor Q130. A resistor R27 is connected between the gate of the MOSFET Q120 and the collector of the transistor Q130. A resistor R28 is connected between the drain of the MOSFET Q120 and the base of the transistor Q130.

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