CN217882885U

CN217882885U - Intelligent household battery protection circuit

Info

Publication number: CN217882885U
Application number: CN202221185543.1U
Authority: CN
Inventors: 钟义
Original assignee: Dongguan Xingkaitai Electronic Technology Co ltd
Current assignee: Dongguan Xingkaitai Electronic Technology Co ltd
Priority date: 2022-05-17
Filing date: 2022-05-17
Publication date: 2022-11-22
Anticipated expiration: 2032-05-17

Abstract

The utility model discloses an intelligence house battery protection circuit relates to battery circuit technical field, including one-level protection circuit and secondary protection circuit and two sets of MOS, one-level protection circuit and secondary protection circuit all include IC, one-level protection circuit IC and secondary protection circuit IC's VDD pin is established ties respectively and is had resistance R1 and resistance R4, and resistance R1 and resistance R4 all parallelly connected insert to the positive circuit of charging and discharging circuit in, one-level protection circuit IC's DO pin and CO pin establish ties with the G1 pin and the G2 pin of one of them MOS respectively. The utility model discloses an increase second grade protection circuit module in the circuit, the protection shield is at the during operation, arbitrary one-level protection inefficacy back, and remaining one-level protection circuit can make the protection shield continue work, and the protection battery effect that whole circuit and component all played lets battery in use avoid appearing the device short circuit on the major loop, leads to the battery overcharge, and the phenomenon is crossed to put and overflow, causes the battery to burn out.

Description

Intelligent household battery protection circuit

Technical Field

The utility model relates to a battery circuit technical field, concretely relates to intelligence house battery protection circuit.

Background

The lithium battery is a primary battery using lithium metal or lithium alloy as a negative electrode material and using a non-aqueous electrolyte solution, unlike a lithium ion battery, which is a rechargeable battery, and a lithium ion polymer battery. The inventor of lithium batteries was edison. Because the chemical characteristics of lithium metal are very active, the requirements on the environment for processing, storing and using the lithium metal are very high. Therefore, lithium batteries have not been used for a long time. With the development of microelectronic technology at the end of the twentieth century, miniaturized devices are increasing, and high requirements are made on power supplies. The lithium cell has got into large-scale practical stage thereupon, all uses the lithium cell in a lot of intelligent homes.

Because the material of the lithium battery determines that the lithium battery cannot be overcharged, overdischarged, overcurrent, short-circuited and charged and discharged at ultrahigh temperature, the performance and the service life of the battery are seriously influenced without the protection effect, and a large amount of gas can be generated.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an intelligence house battery protection circuit to solve the above-mentioned weak point among the prior art.

In order to achieve the above object, the present invention provides the following technical solutions: an intelligent household battery protection circuit comprises a primary protection circuit, a secondary protection circuit and two groups of MOS, wherein the primary protection circuit and the secondary protection circuit both comprise ICs, VDD pins of the primary protection circuit IC and the secondary protection circuit IC are respectively connected in series with a resistor R1 and a resistor R4, the resistor R1 and the resistor R4 are connected in parallel to be connected into an anode circuit of a charging and discharging circuit, a DO pin and a CO pin of the primary protection circuit IC are respectively connected in series with a G1 pin and a G2 pin of one of the MOS, a DO pin and a CO pin of the secondary protection circuit IC are respectively connected in series with a G1 pin and a G2 pin of the other MOS, a S2 pin of the former MOS is connected with a S1 pin of the latter MOS, a S1 pin of the former MOS and a S2 pin of the latter MOS are connected into a cathode circuit of the charging and discharging circuit, a resistor RS is connected in series between a cathode of a battery and the MOS, the MOS transistor is characterized in that a resistor R2 is connected in series with a VM pin of the primary protection circuit IC, the resistor R2 is connected in parallel to the negative circuit, a CS pin of the secondary protection circuit IC is connected in parallel to an S1 pin of an MOS connected with the primary protection circuit IC, a resistor R5 is connected in series with a V-pin of the secondary protection circuit IC, the resistor R5 is connected in parallel to the negative circuit, a capacitor C2 and a capacitor C3 are connected in series between the two MOS and an access point of the negative circuit, a capacitor C1 is connected in series between a VDD pin and a VSS pin of the primary protection circuit IC, the capacitor C1 is grounded, a capacitor C5 is connected in series between the VDD pin and the VSS pin of the secondary protection circuit IC, the capacitor C5 is grounded, a capacitor C4 is connected in parallel between a positive circuit and the negative circuit in the circuit, the negative circuit is connected with a thermistor R3, and the thermistor R3 is used as an NTC.

In the technical scheme, the utility model provides a technological effect and advantage:

the utility model discloses an adopt two sets of protection circuit, increase dipolar protection circuit module promptly in the circuit, one-level protection and dipolar protection collaborative work, the protection shield is at the during operation, arbitrary one-level protection inefficacy back, remaining one-level protection circuit can make the protection shield continue work, the protection battery effect that whole circuit and component all played, let battery in use avoid appearing the device short circuit on the major loop, lead to the battery to cross to fill, cross and put and overflow the phenomenon, cause the battery to burn out, thereby increase of service life, reduce the cost of scrapping.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to these drawings.

Fig. 1 is a schematic circuit diagram of the present invention.

Fig. 2 is a schematic diagram of the circuit state in the normal state of the present invention.

Fig. 3 is a schematic diagram of the circuit state in the overcharge protection state of the present invention.

Fig. 4 is the circuit state diagram of the over-discharge protection state, the over-current protection state and the short-circuit protection state of the present invention.

Fig. 5 is an IC schematic diagram of the present invention.

Fig. 6 is a schematic diagram of a MOS of the present invention.

Fig. 7 is a data diagram of the related test of the present invention.

Description of reference numerals:

u1, U2 are IC (chip), Q1, Q2 are MOS (transistor), R1, R2, R4, R5 and RS are all common resistors, R3 is thermistor NTC, and C1, C2 and C3 are all capacitors.

Detailed Description

In order to make the technical solution of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings.

The utility model provides a smart home battery protection Circuit as shown in figure 1, which comprises a primary protection Circuit and a secondary protection Circuit and two sets of MOS Q1 and Q2, wherein the primary protection Circuit and the secondary protection Circuit both comprise IC U1 and U2, wherein IC represents (Integrated Circuit), MOS is metal-oxide-semiconductor (semiconductor) field effect transistor, and in the Circuit field, IC and MOS are used for representing respectively, the utility model also uses IC and MOS to represent respectively in the whole text, VDD pins of the primary protection Circuit IC U1 and the secondary protection Circuit IC 2 are respectively connected in series with a resistor R1 and a resistor R4, and the resistor R1 and the resistor R4 are both connected in parallel into an anode Circuit of a charging and discharging Circuit, a DO pin and a CO pin of the primary protection Circuit IC U1 are respectively connected in series with a G1 pin and a G2 pin of one of MOS Q1, the DO pin and the CO pin of the secondary protection Circuit IC U2 are respectively connected with the G1 pin and the G2 pin of another MOS Q2 in series, the S2 pin of the MOS Q1 is connected with the S1 pin of the MOS Q2, the S1 pin of the MOS Q1 and the S2 pin of the MOS Q2 are both connected in parallel into a negative electrode Circuit of a charging and discharging Circuit, a resistor RS is connected in series between the negative electrode of the battery and the MOS Q1 and the MOS 2, the VM pin of the primary protection Circuit IC U1 is connected in series with a resistor R2, the resistor R2 is connected in parallel into a negative electrode Circuit, the CS pin of the secondary protection Circuit IC U2 is connected in parallel to the S1 pin of the MOS Q1 connected with the primary protection Circuit IC U1, the V-pin of the secondary protection Circuit IC U2 is connected in series with a resistor R5, and the resistor R5 is connected in parallel into the negative electrode Circuit, the capacitor C2 and the capacitor C3 are arranged between the two MOS and the access point of the negative electrode circuit in series, the capacitor C1 is arranged between the VDD pin and the VSS pin of the first-stage protection circuit IC U1 in series, the capacitor C1 is arranged in a grounding mode, the capacitor C5 is arranged between the VDD pin and the VSS pin of the second-stage protection circuit IC U2 in series, the capacitor C5 is arranged in a grounding mode, the capacitor C4 is connected between the positive electrode circuit and the negative electrode circuit in parallel in the circuit, the negative electrode circuit is connected with the thermistor R3, and the thermistor R3 is used as an NTC.

Wherein, the utility model discloses in use the components and parts material as follows:

the primary protection circuit IC adopts an S-8261DAY type chip, the secondary protection circuit IC adopts an NT1715A-HQB-C1 type chip, and the IC judges by sampling the voltage of the battery; SM9973DSQG type transistor is all adopted to two sets of MOS, and the MOS pipe manages electric core, mainly plays the switching action among the protection plate circuit.

NTC, i.e. R3, is 10K, ± 1%, B =3435 thermistor (temperature measurement, temperature control and temperature compensation of elements, devices and circuits, temperature control is 20-30%); the ID is selected from 100K, ± 1%,1/16W (identification resistance of the intelligent household equipment to the battery).

And R1 and R4 select the benchmark to supply power resistance, and R2 and R5 select overcurrent and detection resistance.

The utility model discloses a circuit has overcharge protect function, overdischarge protect function and overcurrent protection function and short-circuit protection function, and during the circuit normal condition, as shown in fig. 2, "CO" and "DO" pin in one-level protection circuit, the second grade protection circuit all exports the high level, and two MOSFET all are in the on-state, and the battery can freely charge and discharge (after arbitrary one-level protection became invalid, remaining one-level protection circuit can make the protection shield continue work).

The overcharge protection function is to prohibit the charger from continuing to charge when a certain voltage (hereinafter referred to as overcharge detection voltage) is reached, that is, to turn an MOS transistor for controlling overcharge into an off state to stop charging; in the overcharge protection state, as shown in fig. 3, when the control IC detects that the battery voltage reaches 4.3V, the "CO" pin of the control IC changes from high voltage to "L" low level, so that G2 and S2 are switched from on to off, thereby cutting off the charging loop, and the charger cannot charge the battery any more, thereby performing the overcharge protection function (when any one level of protection fails, the remaining one level of protection circuit can make the protection board continue to operate).

The over-discharge protection function stops discharging the load when the voltage of the battery becomes low. The MOS tube for controlling over-discharge enters a turn-off state, and the discharge of the MOS tube is forbidden, and the process is just opposite to the action during the over-charge detection; in the over-discharge protection state, as shown in fig. 4, when the control IC detects that the battery voltage is lower than 2.85V, the "DO" pin of the control IC changes from high voltage to "L" low level, so that G1 and S1 are turned from on to off, thereby cutting off the discharge loop, and the battery cannot discharge the load any more, so as to perform the over-discharge protection function (when any one level of protection fails, the remaining one level of protection circuit can make the protection board continue to operate).

The over-current protection function is to stop discharging the load when consuming large current, and the function aims at protecting the battery and the MOS tube to ensure the safety of the battery in the working state, and after the over-current detection, the battery is recovered to the normal state after being separated from the load and can be recharged or discharged; in the overcurrent protection state, as shown in fig. 4, when the battery discharges the load normally, and the discharge current passes through the 2 MOSFETs connected in series, a voltage is generated at both ends of the MOSFETs due to the on-resistance of the MOSFETs, and the voltage value is detected by the "VM" pin on the control IC, if the load is abnormal for some reason, the loop current is increased, and when the loop current is so large that U is greater than 0.105V, the "DO" pin is changed from the high voltage to the "L" low level, so that G1 and S1 are changed from on to off, thereby cutting off the discharge loop, making the current in the loop zero, and performing the overcurrent protection function (when any one stage of protection fails, the protection board can continue to operate).

The principle of the short-circuit protection function is the same as that of the overcurrent protection function, as shown in fig. 4, when the battery discharges to the load, if the loop current is so large that U is greater than 0.6V, the control IC determines that the load is short-circuited, and the "DO" pin of the control IC rapidly changes from high voltage to zero voltage, so that G1 and S1 are switched from on to off, thereby cutting off the discharge loop and playing a role in short-circuit protection (when any one level of protection fails, the remaining one-level protection circuit can enable the protection board to continue to work); when the NTC detects the temperature condition in the circuit, and the temperature is higher than or lower than the set value in the use process, the equipment can quickly cut off the protection board loop to prevent the battery from continuously charging and discharging.

In summary, the following steps: two groups of protection circuits are adopted, namely a diode protection circuit module is added in the circuit, the primary protection and the diode protection work in a coordinated mode, when the protection board works, after any one-level protection fails, the remaining primary protection circuit can enable the protection board to continue to work, and the whole circuit and elements have the battery protection effect, so that the battery is prevented from being damaged badly when being used.

The protection circuit is developed to be used only for the product, a diode protection module is added in the existing protection circuit to better protect the battery, so that the battery is prevented from being burnt due to the phenomena of overcharge, overdischarge and overcurrent of the battery caused by the short circuit of a device on a main loop when in use, the service life is prolonged, and the scrapping cost is reduced.

While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the present invention. Accordingly, the drawings and description are illustrative in nature and should not be construed as limiting the scope of the invention.

Claims

1. The utility model provides an intelligence house battery protection circuit, includes one-level protection circuit and secondary protection circuit and two sets of MOS (Q1, Q2), its characterized in that: the protection circuit comprises a primary protection circuit and a secondary protection circuit, wherein the primary protection circuit and the secondary protection circuit respectively comprise an IC (U1 and a U2), a VDD pin of the primary protection circuit IC (U1) and a VDD pin of the secondary protection circuit IC (U2) are respectively connected with a resistor (R1) and a resistor (R4) in series, the resistor (R1) and the resistor (R4) are respectively connected in parallel into a positive circuit of a charging and discharging circuit, a DO pin and a CO pin of the primary protection circuit IC (U1) are respectively connected in series with a G1 pin and a G2 pin of one MOS (Q1) in series, a DO pin and a CO pin of the secondary protection circuit IC (U2) are respectively connected in series with a G1 pin and a G2 pin of the other MOS (Q2), an S2 pin of the former MOS (Q1) and an S1 pin of the latter MOS (Q2) are connected in parallel into a negative circuit of the charging and discharging circuit, a cathode of the battery is connected in series with the MOS (Q1, a cathode of the battery and a Resistor (RS) of the MOS (Q2) and a cathode of the MOS (R1) of the secondary protection circuit are connected in parallel into a negative circuit, a cathode (R5) of the secondary protection circuit is connected with a resistor (R2) and a discharge circuit, and a resistor (RS 5) of the MOS (R2) are connected in parallel into a discharge circuit, and a cathode of the MOS (U1 and a cathode of the MOS (R2) and a resistor (R5, and a resistor (R2) of the MOS (R2) are connected in series connected in parallel into a discharge circuit, and a resistor (R5 is connected in series connected in parallel into a discharge circuit.

2. The smart home battery protection circuit according to claim 1, characterized in that: a capacitor (C2) and a capacitor (C3) are arranged in series between the two MOS and the access point of the negative electrode circuit.

3. The smart home battery protection circuit according to claim 1, characterized in that: a capacitor (C1) is connected in series between a VDD pin and a VSS pin of the primary protection circuit IC (U1), and the capacitor (C1) is grounded.

4. The smart home battery protection circuit according to claim 1, characterized in that: a capacitor (C5) is connected in series between a VDD pin and a VSS pin of the secondary protection circuit IC (U2), and the capacitor (C5) is grounded.

5. The smart home battery protection circuit according to claim 1, characterized in that: a capacitor (C4) is connected in parallel between the positive circuit and the negative circuit in the circuit.

6. The smart home battery protection circuit according to claim 1, characterized in that: the negative circuit is connected with a thermistor (R3), and the thermistor (R3) is used as an NTC.