Battery hardware tamper circuit and lithium battery

Abstract

The utility model provides a battery hardware anti-tamper circuit and a lithium battery, the battery hardware anti-tamper circuit comprises a first input circuit, a second input circuit and an output circuit, the first input circuit comprises an optical sensor, a first control tube, a first divider resistor and a second divider resistor, and the first divider resistor and the second divider resistor are connected in series; the second input circuit comprises a first resistor and a second control tube. The output circuit comprises a second resistor and a protection diode. The circuit can determine whether the batteries are normal or not according to the characteristics of the optical sensor, when the batteries are grouped, the resistance value of the optical sensor is extremely large, and the control port outputs a low-level signal; when the battery is illegally disassembled, the resistance value of the optical sensor is small, the control port outputs a high-level signal, the circuit locks the state that the battery is illegally disassembled, the circuit is further provided with a reset port, the circuit is used for preventing false triggering of anti-disassembly protection in the battery production process and after-sales service, and the circuit is easy to achieve, simple in logic and high in reliability.

Description

Technical Field

[0001] The present disclosure relates to the technical field of lithium batteries, and in particular to a battery hardware anti-disassembly circuit and a lithium battery. Background Art

[0002] After the battery is modified or disassembled, the battery safety performance decreases. It is difficult for users to ensure the safety of the battery when using the modified or disassembled battery, and it is impossible to determine the probability of battery failure. Therefore, it is quite necessary to design a reliable and low-power anti-disassembly protection circuit.

[0003] To this end, the Chinese patent with publication number CN208134099U proposes a battery and a battery anti-disassembly protection circuit thereof, including a detection module, a main control module, a storage module and a charge and discharge control module; the output end of the detection module is connected to the input end of the main control module, the output end of the main control module is respectively connected to the input end of the storage module and the control end of the charge and discharge control module, and the output end of the charge and discharge control module is connected to the battery.

[0004] The technical solution of the above patent detects whether the battery has been disassembled through the detection module, and outputs a detection signal when the battery has been disassembled so that the main control module outputs a control signal to the storage module and the charge and discharge control module, controls the storage module to store the fault state, and controls the charge and discharge control module to output a shutdown control signal to control the battery not to perform charge and discharge operations. However, during the battery production process and after-sales service, the detection module is prone to mistakenly trigger the anti-disassembly protection. Furthermore, if the battery is disassembled due to normal battery production or normal after-sales service, it will also cause the battery status to be locked. As a result, the reliability of the above anti-disassembly protection circuit is low.

[0005] Therefore, there is a need for an anti-tampering circuit that can prevent false triggering of the anti-tampering protection and has high reliability. Utility Model Content

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a battery hardware anti-tampering circuit and a lithium battery that can prevent false triggering of anti-tampering protection and have high reliability.

[0007] The purpose of this disclosure is achieved through the following technical solutions:

[0008] A battery hardware anti-tampering circuit, comprising:

[0009] A first input circuit, the first input circuit comprises a light sensor, a first control tube, a first voltage-dividing resistor and a second voltage-dividing resistor connected in series, the first end of the light sensor is connected to a reference power supply, the second end of the light sensor is connected to a control end of the first control tube through the first voltage-dividing resistor, the control end of the first control tube is also grounded through the second voltage-dividing resistor, and the second end of the first control tube is grounded;

[0010] a second input circuit, the second input circuit comprising a first resistor and a second control tube, the control end of the second control tube being connected to the first end of the first control tube, the control end of the second control tube being connected to the first end of the second control tube through the first resistor, and the first end of the second control tube being connected to a reference power supply;

[0011] An output circuit includes a second resistor and a protection diode, the second end of the second control tube is connected to the control port through the second resistor, the second end of the second control tube is also connected to the control end of the first control tube through the second resistor, the second end of the second control tube is also connected to the anode of the protection diode through the second resistor, and the cathode of the protection diode is connected to the reset port.

[0012] In one embodiment, the second input circuit further includes a third resistor, the first end of the first control tube is connected to the control end of the second control tube through the third resistor, and the first end of the first control tube is connected to a reference power supply through the third resistor and the first resistor in sequence.

[0013] In one embodiment, the output circuit further includes a first filter capacitor, and the second end of the second control tube is grounded via the second resistor and the first filter capacitor in sequence.

[0014] In one embodiment, the output circuit further includes a second filter capacitor, and the cathode of the protection diode is grounded through the second filter capacitor.

[0015] In one embodiment, at least one of the first voltage-dividing resistor and the second voltage-dividing resistor is an adjustable resistor.

[0016] In one embodiment, a resistance ratio of the first voltage-dividing resistor to the second voltage-dividing resistor is 1:48 to 1:52.

[0017] In one embodiment, the first resistor is an adjustable resistor.

[0018] In one embodiment, at least one of the second resistor and the third resistor is an adjustable resistor.

[0019] In one embodiment, the first control transistor is an NMOS transistor; and / or the second control transistor is a PMOS transistor.

[0020] A lithium battery comprises the battery hardware anti-disassembly circuit described in any one of the above embodiments.

[0021] Compared with the prior art, the present invention has at least the following advantages:

[0022] 1. The above-mentioned battery hardware anti-disassembly circuit can determine whether the battery is normal or not according to the characteristics of the light sensor. When the batteries are grouped, the resistance of the light sensor is extremely large, the first control tube and the second control tube are in the off state, and the control port outputs a low-level signal; when the battery is illegally disassembled, the resistance of the light sensor is small, the first control tube and the second control tube are turned on in turn, and the control port outputs a high-level signal. The circuit locks the state of the battery being illegally disassembled. The circuit is easy to implement and has simple logic.

[0023] 2. The above circuit is also provided with a reset port, which is used to prevent the anti-disassembly protection from being triggered accidentally during the battery production process and after-sales service. The reset port is used by the MCU to pull down the high level of the control port through the protection diode to restore the initial state, thereby having higher reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 FIG. 4 is a circuit diagram of a battery hardware anti-tampering circuit in an embodiment.

[0026] Figure numerals: 10, battery hardware anti-disassembly circuit; 100, first input circuit; 200, second input circuit; 300, output circuit; R1, second resistor; R2, first resistor; R3, third resistor; R4, first voltage-dividing resistor; R5, second voltage-dividing resistor; D1, protection diode; D2, light sensor; M1, second control tube; M2, first control tube; C1, first filter capacitor; C2, second filter capacitor; MCU_IO1, control port; MCU_IO2, reset port. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the present disclosure, the present disclosure will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present disclosure more thoroughly and comprehensively understood.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present disclosure. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0030] The present disclosure provides a battery hardware anti-disassembly circuit, comprising a first input circuit, a second input circuit and an output circuit, wherein the first input circuit comprises a light sensor, a first control tube, a first voltage-dividing resistor and a second voltage-dividing resistor connected in series, wherein the first end of the light sensor is connected to a reference power supply, the second end of the light sensor is connected to a control end of the first control tube through the first voltage-dividing resistor, the control end of the first control tube is also grounded through the second voltage-dividing resistor, and the second end of the first control tube is grounded; the second input circuit comprises a first resistor and a second control tube, the control end of the second control tube is connected to the first end of the first control tube, the control end of the second control tube is connected to the first end of the second control tube through the first resistor, and the first end of the second control tube is connected to the reference power supply; the output circuit comprises a second resistor and a protection diode, the second end of the second control tube is connected to a control port through the second resistor, the second end of the second control tube is also connected to the control end of the first control tube through the second resistor, the second end of the second control tube is also connected to the anode of the protection diode through the second resistor, and the cathode of the protection diode is connected to a reset port.

[0031] The above-mentioned battery hardware anti-disassembly circuit can determine whether the battery is normal or not according to the characteristics of the light sensor. When the battery is grouped, the resistance of the light sensor is extremely large, the first control tube and the second control tube are in the off state, and the control port outputs a low-level signal; when the battery is illegally disassembled, the resistance of the light sensor is small, the first control tube and the second control tube are turned on in sequence, and the control port outputs a high-level signal. The circuit locks the state of the battery being illegally disassembled. The circuit is easy to implement and has simple logic. In addition, the circuit is also provided with a reset port, which is used to prevent the anti-disassembly protection from being falsely triggered during the battery production process and after-sales service. The reset port is used for the MCU to pull down the high level of the control port through the protection diode to restore the initial state, thereby having high reliability.

[0032] In order to better understand the technical solutions and beneficial effects of the present invention, the present invention is further described in detail below in conjunction with specific embodiments:

[0033] See also Figure 1 , which is a battery hardware anti-disassembly circuit 10 of an embodiment of the utility model, including a first input circuit 100, a second input circuit 200 and an output circuit 300. The first input circuit 100 includes a light sensor D2, a first control tube M2, a first voltage-dividing resistor R4 and a second voltage-dividing resistor R5 connected in series. The first end of the light sensor D2 is connected to a reference power supply, and the second end of the light sensor D2 is connected to the control end of the first control tube M2 through the first voltage-dividing resistor R4. The control end of the light sensor D2 is used to receive a light source to change its own resistance value. Specifically, when the light sensor D2 receives a light source, the resistance value is small, and when the light sensor D2 does not receive a light source, the resistance value is large. The control end of the first control tube M2 is also grounded through the second voltage-dividing resistor R5. The second end of the tube M2 is grounded; the second input circuit 200 includes a first resistor R2 and a second control tube M1, the control end of the second control tube M1 is connected to the first end of the first control tube M2, the control end of the second control tube M1 is connected to the first end of the second control tube M1 through the first resistor R2, and the first end of the second control tube M1 is connected to the reference power supply; the output circuit 300 includes a second resistor R1 and a protection diode D1, the second end of the second control tube M1 is connected to the control port MCU_IO1 through the second resistor R1, the second end of the second control tube M1 is also connected to the control end of the first control tube M2 through the second resistor R1, the second end of the second control tube M1 is also connected to the anode of the protection diode D1 through the second resistor R1, and the cathode of the protection diode D1 is connected to the reset port MCU_IO2.

[0034] The above-mentioned battery hardware anti-tampering circuit 10 is implemented as follows:

[0035] After the batteries are grouped, the BMS and the battery cell group are sealed inside the battery housing, and the optical sensor D2 is in a sealed environment. At this time, its internal resistance is in the megohm level (MΩ). The first voltage-dividing resistor R4 and the second voltage-dividing resistor R5 are connected in series to divide the voltage. The voltage drop generated by the second voltage-dividing resistor R5 cannot reach the conduction condition for turning on the first control tube M2 (the conduction condition is that the control terminal voltage of the first control tube M2 is greater than the second terminal voltage). The current passes through the first resistor R2, and the control terminal of the second control tube M1 is pulled to a high level, so that the second control tube M1 cannot be turned on (the conduction condition is that the control terminal voltage of the second control tube M1 is less than the first terminal voltage). The current flows through the first voltage-dividing resistor R4 to the control port MCU_IO1, and the second voltage-dividing resistor R5 pulls the control port MCU_IO1 down to a low level. At this time, the battery is in a normal state; When the battery is illegally disassembled, the light sensor D2 is no longer in a sealed environment. At this time, its internal resistance is in the kilo-ohm level (KΩ). The first voltage-dividing resistor R4 and the second voltage-dividing resistor R5 are connected in series to divide the voltage. The voltage drop generated by the second voltage-dividing resistor R5 will turn on the first control tube M2. The current also passes through the first resistor R2 and the first control tube M2 to ground in sequence. Since the first resistor R2 also generates a voltage drop, the second control tube M1 is turned on, and the current outputs a high-level signal to the control port MCU_IO1. The current of the reference power supply passes through the second control tube M1, the second voltage-dividing resistor R5 and the second resistor R1 to divide the voltage to ground in sequence. After the microcontroller unit (MCU) recognizes the high level, it controls other logic circuits, records the illegal disassembly status and locks the battery status. The high-level signal can also be fed back to the control end of the first control tube M2 to enhance the stability of the input end. Specifically, the light sensor D2 is used to determine whether there is a light source to determine the high and low levels of the control port MCU_IO1.

[0036] In addition, the circuit is also provided with a reset port MCU_IO2. When the anti-disassembly protection is mistakenly triggered during the production process or after-sales service, the reset port MCU_IO2 can pull down the high level of the control port MCU_IO1 through the protection diode D1, so that the battery returns to its original state.

[0037] In this embodiment, the first control tube M2 is an NMOS tube, the first end of the first control tube M2 is a drain electrode D, the second end of the first control tube M2 is a source electrode S, which is used for grounding, and the control end of the first control tube M2 is a gate electrode G; the second control tube M1 is a PMOS tube, the first end of the second control tube M1 is a source electrode S, which is used for connecting to a reference power supply, the second end of the second control tube M1 is a drain electrode D, and the control end of the second control tube M1 is a gate electrode G; the light sensor D2 is a phototransistor, the first end of the light sensor D2 is a collector electrode c, the second end of the light sensor D2 is an emitter electrode e, and the control end of the light sensor D2 is used to receive a light source to change the resistance value of the light sensor D2 itself according to the light source. The following embodiments can all be described.

[0038] In one embodiment, the second input circuit 200 further includes a third resistor R3, the first end of the first control transistor M2 is connected to the control end of the second control transistor M1 through the third resistor R3, and the first end of the first control transistor M2 is connected to the reference power supply through the third resistor R3 and the first resistor R2 in sequence. Furthermore, the first resistor R2 and the third resistor R3 are connected in series to divide the voltage, which can further protect the first end of the first control transistor M2 and prevent the first end of the first control transistor M2 from being damaged by excessive current breaking through the first end of the first control transistor M2.

[0039] In one embodiment, the output circuit 300 further includes a first filter capacitor C1, and the second end of the second control tube M1 is grounded through the second resistor R1 and the first filter capacitor C1 in sequence. Furthermore, the output level signal is also stored in the upper half of the first filter capacitor C1, and the lower half is grounded, so that the level output by the control port MCU_IO1 can be filtered, the interference of redundant signals can be reduced, and the circuit can be ensured.

[0040] In one embodiment, the output circuit 300 further includes a second filter capacitor C2, and the cathode of the protection diode D1 is grounded through the second filter capacitor C2. Further, when the control port MCU_IO1 outputs a high-level signal, the reset port MCU_IO2 pulls down the high-level signal of the control port MCU_IO1. At this time, the level signal passes through the protection diode D1, and the upper part of the second filter capacitor C2 stores electricity, and the lower part is grounded. In this way, the level of the reset port MCU_IO2 can be filtered, the interference of redundant signals can be reduced, and the circuit can be ensured.

[0041] In one embodiment, at least one of the first voltage-dividing resistor R4 and the second voltage-dividing resistor R5 is an adjustable resistor. In this embodiment, by adjusting the resistance value of the first voltage-dividing resistor R4 or the second voltage-dividing resistor R5, the conduction condition of the first control tube M2 is adjusted to be suitable for different models of the first control tube M2. Further, the model of the first control tube M2 can be SI2312DS.

[0042] In one embodiment, the resistance ratio of the first voltage-dividing resistor R4 to the second voltage-dividing resistor R5 is 1:48 to 1:52. In this embodiment, the resistance ratio of the first voltage-dividing resistor R4 to the second voltage-dividing resistor R5 is 1:51.

[0043] Specifically, assuming that the reference power supply voltage is 3.3V, the resistance of the first voltage-dividing resistor R4 and the third resistor R3 is 10KΩ, the resistance of the second voltage-dividing resistor R5, the first resistor R2, and the second resistor R1 is 510KΩ, and when the optical sensor D2 is in a sealed environment, its resistance is at the megohm level (assuming it is 10MΩ). According to the voltage-dividing ratio (D2+R4) / R5, it is approximately (10MΩ+10KΩ) / 510KΩ. The voltage-dividing ratio of the control end of the first control tube M2 does not reach the condition for turning on the first control tube M2, and the current size is VCC / (D2+R4+R 5) is at the microampere level (μA), and the power consumption is low; when the battery is illegally disassembled, the resistance of the light sensor D2 is at the kilo-ohm level (assuming it is 10KΩ), and according to the voltage divider ratio (D2+R4) / R5, it is approximately (10KΩ+10KΩ) / 510KΩ, turning on the first control tube M2, and the current connects the first resistor R2, the third resistor R3 and the first end and the second end of the first control tube M2 to the ground, turning on the second control tube M1, and the current is also divided by the second resistor R1 and the second voltage divider resistor R5 to the ground. At this time, the control port MCU_IO1 is at a high level.

[0044] In one embodiment, the first resistor R2 is an adjustable resistor. Further, by adjusting the resistance of the first resistor R2, the conduction condition of the second control tube M1 can be adjusted to be suitable for different models of the second control tube M1. Specifically, the model of the second control tube M1 can be SVT03380PSA.

[0045] In one embodiment, at least one of the second resistor R1 and the third resistor R3 is an adjustable resistor.

[0046] Specifically, the setting of the second resistor R1 can further protect the diode D1, so as to reduce the possibility of the current breaking through the protection diode D1 due to excessive current. Furthermore, by adjusting the resistance value of the second resistor R1, the voltage of the second end of the second control tube M1 can be dynamically adjusted; the setting of the third resistor R3 can further protect the first control tube M2, so as to further reduce the possibility of the current breaking through the first end of the first control tube M2 due to excessive current. By adjusting the resistance value of the third resistor R3, the voltage of the first end of the first control tube M2 can be dynamically adjusted, and the circuit withstand voltage value can be increased.

[0047] In one embodiment, the first control transistor M2 is an NMOS transistor; and / or the second control transistor M1 is a PMOS transistor. Details will not be given here.

[0048] The present disclosure further provides a lithium battery, comprising the battery hardware anti-tampering circuit 10 of any of the above embodiments.

[0049] Compared with the prior art, the present invention has at least the following advantages:

[0050] 1. The battery hardware anti-disassembly circuit 10 can determine whether the battery is normal or not according to the characteristics of the light sensor D2. When the battery is grouped, the resistance of the light sensor D2 is extremely large, the first control tube M2 and the second control tube M1 are in the off state, and the control port MCU_IO1 outputs a low-level signal; when the battery is illegally disassembled, the resistance of the light sensor D2 is small, the first control tube M2 and the second control tube M1 are turned on in sequence, and the control port MCU_IO1 outputs a high-level signal, and the circuit locks the state of the battery being illegally disassembled. The circuit is easy to implement and has simple logic.

[0051] 2. The above circuit is also provided with a reset port MCU_IO2, which is used to prevent the anti-disassembly protection from being triggered accidentally during the battery production process and after-sales service. The reset port MCU_IO2 is used by the MCU to pull down the high level of the control port MCU_IO1 through the protection diode D1 to restore the initial state, thereby having higher reliability.

[0052] The above-mentioned embodiments only express several implementation methods of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the disclosed patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the disclosed patent shall be subject to the attached claims.

Claims

1. A battery hardware anti-tampering circuit, characterized in that: include: A first input circuit, the first input circuit comprises a light sensor, a first control tube, a first voltage-dividing resistor and a second voltage-dividing resistor connected in series, the first end of the light sensor is connected to a reference power supply, the second end of the light sensor is connected to a control end of the first control tube through the first voltage-dividing resistor, the control end of the first control tube is also grounded through the second voltage-dividing resistor, and the second end of the first control tube is grounded; a second input circuit, the second input circuit comprising a first resistor and a second control tube, the control end of the second control tube being connected to the first end of the first control tube, the control end of the second control tube being connected to the first end of the second control tube through the first resistor, and the first end of the second control tube being connected to a reference power supply; An output circuit includes a second resistor and a protection diode, the second end of the second control tube is connected to the control port through the second resistor, the second end of the second control tube is also connected to the control end of the first control tube through the second resistor, the second end of the second control tube is also connected to the anode of the protection diode through the second resistor, and the cathode of the protection diode is connected to the reset port.

2. The battery hardware anti-disassembly circuit according to claim 1, characterized in that: The second input circuit also includes a third resistor, the first end of the first control tube is connected to the control end of the second control tube through the third resistor, and the first end of the first control tube is connected to the reference power supply through the third resistor and the first resistor in sequence.

3. The battery hardware anti-tampering circuit according to claim 1, characterized in that: The output circuit also includes a first filter capacitor, and the second end of the second control tube is grounded through the second resistor and the first filter capacitor in sequence.

4. The battery hardware anti-tampering circuit according to claim 1, characterized in that: The output circuit further includes a second filtering capacitor, and the cathode of the protection diode is grounded through the second filtering capacitor.

5. The battery hardware anti-tampering circuit according to claim 1, characterized in that: At least one of the first voltage-dividing resistor and the second voltage-dividing resistor is an adjustable resistor.

6. The battery hardware anti-tampering circuit according to claim 1, characterized in that: The resistance ratio of the first voltage-dividing resistor to the second voltage-dividing resistor is 1:48 to 1:

52.

7. The battery hardware anti-tampering circuit according to claim 1, characterized in that: The first resistor is an adjustable resistor.

8. The battery hardware anti-tampering circuit according to claim 2, characterized in that: At least one of the second resistor and the third resistor is an adjustable resistor.

9. The battery hardware anti-tampering circuit according to claim 1, characterized in that: The first control transistor is an NMOS transistor; and / or, The second control tube is a PMOS tube.

10. A lithium battery, characterized in that: The invention comprises the battery hardware anti-disassembly circuit as described in any one of claims 1 to 9.

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