Charging and discharging circuit based on battery cell and battery compartment

Abstract

The utility model discloses a charging and discharging circuit based on a battery cell and a battery compartment, and relates to the technical field of power electronics. The electric core and the charging and discharging protection circuit are connected through the connector, the electric core is separated from the protection plate and located above the protection plate, and the charging and discharging protection circuit is located at the protection plate; the charging and discharging protection circuit is connected with the controller; and the controller is used for performing charging and discharging protection on the battery cell through software protection when the charging and discharging protection circuit is abnormal. The charging and discharging protection circuit is isolated from the battery cell through the connector, a battery pack and a battery bin do not need to be customized, and the compatibility of a product is improved. According to the charging and discharging protection circuit, the charging circuit for charging the battery cell and the discharging circuit for charging the product by the battery cell are integrated in one circuit, so that the charging safety is ensured, the battery cell can be charged in the product, the product can be normally used in the charging process, and the cost is reduced. And if the battery cell is abnormal, charging and discharging protection is provided for software of the battery cell through the controller, so that the reliability of the product is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a charging and discharging circuit based on a battery cell and a battery compartment. Background Art

[0002] When standard specification batteries are used to power devices, the following two methods are usually used to ensure charging safety. The first method is based on the battery charging and discharging protection board. The protection board is fixed on the battery cell, and the battery pack with the protection board is placed in the device for charging and discharging. However, this battery pack is customized and can only be purchased by end customers through designated sales channels. Moreover, since the battery pack is larger than the standard battery cell, the battery compartment also needs to be customized when the battery pack is customized, which leads to poor compatibility of charging products. The second method is to equip the battery cell with an additional battery charging stand, that is, when the battery cell is out of power, it is removed from the device and placed on the charging stand for charging. The charging stand only provides charging protection. However, the disadvantage of this method is that if the problem of being unable to use the device when the battery cell is out of power is to be avoided, the end customer must prepare multiple batteries and use the spare battery cell to power the product when the main battery cell is charged, which increases the cost investment. In addition, the addition of an additional battery charging stand makes it impossible to integrate charging and discharging in one circuit board, which occupies additional device area and increases the corresponding cost.

[0003] Therefore, how to ensure charging safety while improving the compatibility of charging products and reducing occupied area and cost is a technical problem that technical personnel in this field urgently need to solve. Utility Model Content

[0004] The purpose of the utility model is to provide a charging and discharging circuit and a battery compartment based on a battery cell, so as to solve the technical problems that the current battery cells power the equipment, resulting in poor compatibility of charging products due to the customization of battery packs and battery compartments, and the need for an additional battery cell charging stand to power the battery cells, which occupies additional device area and increases costs.

[0005] In order to solve the above technical problems, the utility model provides a charge and discharge circuit based on a battery cell, the charge and discharge circuit includes a connector, a charge and discharge protection circuit and a controller;

[0006] The connector is used to connect the battery cell and the charge-discharge protection circuit, wherein the battery cell is separated from the protection board and is located above the protection board, and the charge-discharge protection circuit is located at the protection board;

[0007] The charge and discharge protection circuit is connected to the controller;

[0008] The controller is used to perform charge and discharge protection on the battery cell through software protection when the charge and discharge protection circuit is abnormal.

[0009] On the one hand, the charge and discharge protection circuit includes a primary charge and discharge protection circuit and a secondary charge and discharge protection circuit;

[0010] The primary charge and discharge protection circuit is connected to the connector and the secondary charge and discharge protection circuit respectively;

[0011] The secondary charge and discharge protection circuit is connected to the controller.

[0012] On the other hand, the primary charge and discharge protection circuit at least includes an overcharge protection circuit, a first transistor, a second transistor and a first charge and discharge chip;

[0013] The overcharge protection circuit comprises a first resistor and a first capacitor, wherein the first end of the first resistor is respectively connected to the first end of the connector and the secondary charge and discharge protection circuit, and the second end of the first resistor is respectively connected to the first end of the first charge and discharge chip and the first end of the first capacitor;

[0014] The second end of the first capacitor is respectively connected to the second end of the connector and the second end of the first charge-discharge chip;

[0015] The control end of the first transistor is connected to the third end of the first charge and discharge chip; the first end of the first transistor is connected to the second end of the connector; the second end of the first transistor is connected to the first end of the second transistor;

[0016] The control end of the second transistor is connected to the fourth end of the first charge and discharge chip; the second end of the second transistor is grounded.

[0017] On the other hand, the primary charge and discharge protection circuit also includes an over-discharge protection circuit and an over-current protection circuit;

[0018] The overcurrent protection circuit includes a second resistor; a first end of the second resistor is respectively connected to the second end of the connector and the second end of the first charge-discharge chip; a second end of the second resistor is respectively connected to the fifth end of the first charge-discharge chip and the first end of the first transistor;

[0019] The over-discharge protection circuit includes a third resistor; a first end of the third resistor is connected to the sixth end of the first charge and discharge chip, and a second end of the third resistor is connected to the second end of the second transistor and is grounded.

[0020] On the other hand, the first-level charge and discharge protection circuit further includes a second capacitor, a third capacitor and a fourth capacitor;

[0021] The first end of the second capacitor is respectively connected to the second end of the second resistor, the fifth end of the first charge-discharge chip and the first end of the first transistor; the second end of the second capacitor is connected to the first end of the third capacitor;

[0022] The second end of the third capacitor is respectively connected to the second end of the second transistor and the second end of the third resistor, and is grounded;

[0023] The first end of the fourth capacitor is connected to the secondary charge and discharge protection circuit; the second end of the fourth capacitor is grounded.

[0024] On the other hand, it also includes ESD protection circuits;

[0025] The ESD protection circuit is connected to the connector and the charge and discharge protection circuit respectively, wherein the ESD protection circuit is a bidirectional TVS tube.

[0026] On the other hand, it also includes an anti-reverse connection circuit, which includes a fifth capacitor, a sixth capacitor, a third transistor, a fourth transistor, a fourth resistor and a fifth resistor, wherein the third transistor is a PMOS transistor and the fourth transistor is an NMOS transistor;

[0027] The control end of the third transistor is respectively connected to the second end of the connector and the second end of the fourth transistor, the first end of the third transistor is connected to the first end of the connector, and the second end of the third transistor is connected to the control end of the fourth transistor;

[0028] The first end of the fourth transistor is connected to the charge and discharge protection circuit; the first end of the fifth capacitor is respectively connected to the first end of the connector and the first end of the third transistor; the second end of the fifth capacitor is respectively connected to the second end of the third transistor and the control end of the fourth transistor;

[0029] The first end of the sixth capacitor is respectively connected to the control end of the third transistor and the second end of the fourth transistor; the second end of the sixth capacitor is respectively connected to the first end of the fourth transistor and the charge and discharge protection circuit;

[0030] The first end of the fourth resistor is connected to the first end of the third transistor, and the second end of the fourth resistor is connected to the second end of the fourth transistor;

[0031] The first end of the fifth resistor is connected to the second end of the third transistor, and the second end of the fifth resistor is connected to the first end of the fourth transistor.

[0032] On the other hand, it also includes a power detection module;

[0033] The electric quantity detection module is connected to the charge and discharge protection circuit and the controller respectively.

[0034] On the other hand, it also includes a temperature detection circuit;

[0035] The temperature detection circuit is connected to the power detection module and the charge and discharge protection circuit respectively, wherein the temperature detection circuit is a thermistor.

[0036] In order to solve the above technical problems, the utility model also provides a battery compartment, including a battery cell and the above-mentioned charging and discharging circuit based on the battery cell.

[0037] The utility model provides a charge and discharge circuit based on a battery cell, and the charge and discharge circuit includes a connector, a charge and discharge protection circuit and a controller; the connector is used to connect the battery cell and the charge and discharge protection circuit, wherein the battery cell is separated from the protection board and is located above the protection board, and the charge and discharge protection circuit is located at the protection board; the charge and discharge protection circuit is connected to the controller; the controller is used to charge and discharge the battery cell through software protection when the charge and discharge protection circuit is abnormal. The charge and discharge protection circuit is isolated from the battery cell by the connector, and further, by setting the positions of the battery cell, the protection board and the charge and discharge protection circuit, there is no need to customize the battery pack and the battery compartment, thereby improving the compatibility of the product. The charge and discharge protection circuit in the utility model integrates the charging circuit for the battery cell and the discharge circuit for charging the product by the battery cell into one circuit, while ensuring charging safety, the battery cell can be charged in the product, and the product can be used normally during the charging process, thereby reducing costs. In addition, considering that if an abnormal situation occurs in the battery cell, the controller provides software charge and discharge protection for the battery cell to improve the reliability of the product.

[0038] The utility model also provides a battery compartment, which has the same beneficial effects as the above-mentioned charging and discharging circuit based on the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present utility model, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A circuit diagram of a charging and discharging circuit based on a battery cell provided in an embodiment of the utility model;

[0041] Figure 2 A structural diagram of a protection plate and a battery cell separated according to an embodiment of the utility model;

[0042] Figure 3 A circuit diagram of another charging and discharging circuit based on a battery cell provided in an embodiment of the utility model.

[0043] The accompanying drawings are marked as follows: 1 is a battery cell, 2 is a connector, 3 is a charge and discharge protection circuit, 4 is a controller, 5 is a primary charge and discharge protection circuit, 6 is a power detection module, 7 is a temperature detection circuit, 8 is an ESD protection circuit, 9 is an anti-reverse connection circuit, and 10 is an energy storage module. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.

[0045] The core of the utility model is to provide a charging and discharging circuit and a battery compartment based on battery cells, so as to solve the technical problems that the current battery cells power the equipment, resulting in poor compatibility of charging products due to the customization of battery packs and battery compartments, and the need for additional battery charging seats to power the battery cells, which occupies additional device area and increases costs.

[0046] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0047] The current battery cell charging and discharging protection plate is fixed on the battery cell, and the battery pack with the protection plate is placed in the device for charging and discharging. Since the battery pack is larger than the standard battery cell, the battery pack and its battery compartment also need to be customized according to the customized size of the battery pack. In addition, for end customers, the battery pack and battery compartment can only be purchased through designated sales channels. Considering the problem that the device cannot be used when the battery cell is out of power, the end customer needs to prepare multiple battery cells and equip the battery cell with a battery charging stand. Therefore, while ensuring the charging and discharging of the battery cell, the battery cell-based charging and discharging circuit provided by the utility model can solve the above technical problems.

[0048] Figure 1 A circuit diagram of a charging and discharging circuit based on a battery cell provided in an embodiment of the utility model, such as Figure 1 As shown, the charge and discharge circuit includes a connector 2, a charge and discharge protection circuit 3 and a controller 4;

[0049] The battery cell 1 and the charge-discharge protection circuit 3 are connected through the connector 2, wherein the battery cell 1 is separated from the protection board and is located above the protection board, and the charge-discharge protection circuit 3 is located at the protection board;

[0050] The charge and discharge protection circuit 3 is connected to the controller 4;

[0051] The controller 4 is used to perform charge and discharge protection on the battery cell 1 through software protection when the charge and discharge protection circuit 3 is abnormal.

[0052] The charge and discharge protection circuit is based on charging the battery cell 1 when the battery cell 1 has no electricity; and discharging the battery cell 1 when the battery cell 1 normally powers the device. The connector 2 in this embodiment is a bridge for connecting the battery cell 1 and the charge and discharge protection circuit 3. The left side of the connector 2 is connected to the battery cell 1, and the right side is connected to the charge and discharge protection circuit 3. The number of protection circuits inside the charge and discharge protection circuit 3 is not limited, and can be one or more. Multiple charge and discharge protection circuits 3 play the role of main and standby charge and discharge protection circuits. If the main charge and discharge protection circuit cannot work normally for the battery cell 1, the standby charge and discharge protection circuit at this time can be upgraded to the main one to work normally to maintain the current operation of the battery cell 1. In addition, the controller 4 in this embodiment is connected to the charge and discharge protection circuit 3. If the charge and discharge protection circuit 3 cannot work normally, in order to protect the battery cell 1 at this time, on the basis of the original hardware circuit over-discharge protection, software over-discharge protection is added to make the battery cell 1 have a longer service life.

[0053] It should be noted that the number of protection circuits in the charge and discharge protection circuit 3 in this embodiment is not limited and can be set according to actual conditions.

[0054] The protection board in this embodiment is used to protect the charge and discharge protection circuit. Figure 2 A structural diagram of a protection plate and a battery cell separated according to an embodiment of the utility model is provided, such as Figure 2 As shown, the protection board is located below the battery cell 1, and a charge and discharge protection circuit is set in the protection board. The battery cell 1 is separated from the protection board to avoid the existing protection board being fixed on the battery cell 1, resulting in the need to customize the battery pack with the protection board. In the utility model, due to the separation structure of the battery cell 1 and the protection board, the battery pack and the battery compartment do not need to be customized, thereby improving the universal compatibility of the product.

[0055] The embodiment of the utility model provides a charge and discharge circuit based on a battery cell, and the charge and discharge circuit includes a connector, a charge and discharge protection circuit and a controller; the battery cell and the charge and discharge protection circuit are connected by a connector, wherein the battery cell is separated from the protection board and is located above the protection board, and the charge and discharge protection circuit is located at the protection board; the charge and discharge protection circuit is connected to the controller; the controller is used to charge and discharge the battery cell through software protection when the charge and discharge protection circuit is abnormal. The charge and discharge protection circuit is isolated from the battery cell by a connector, and further, by setting the positions of the battery cell, the protection board and the charge and discharge protection circuit, there is no need to customize the battery pack and the battery compartment, thereby improving the compatibility of the product. The charge and discharge protection circuit in the utility model integrates the charging circuit for the battery cell and the discharge circuit for charging the product by the battery cell into one circuit, while ensuring charging safety, the battery cell can be charged in the product, and the product can be used normally during the charging process, thereby reducing costs. In addition, considering that if an abnormal situation occurs in the battery cell, the controller provides software charge and discharge protection for the battery cell to improve the reliability of the product.

[0056] Based on the above embodiments, in some embodiments, there are multiple protection circuits in the charge and discharge protection circuit, such as Figure 1 As shown, the charge and discharge protection circuit 3 includes a primary charge and discharge protection circuit 5 and a secondary charge and discharge protection circuit;

[0057] Connect the battery cell and the primary charge and discharge protection circuit 5 via the connector 2;

[0058] The primary charge and discharge protection circuit 5 is connected to the secondary charge and discharge protection circuit;

[0059] The secondary charge and discharge protection circuit is connected to the controller 4 .

[0060] Specifically, the primary charge and discharge protection circuit 5 performs normal charge and discharge of the battery cell 1, and the secondary charge and discharge protection circuit prevents the primary charge and discharge protection circuit 5 from failing, making the battery cell 1 and the entire device system safer to use. The primary charge and discharge protection circuit 5 and the secondary charge and discharge protection circuit play a dual role in protecting the battery cell 1 in this embodiment.

[0061] The specific circuit components in each level of charge and discharge protection circuit may be the same or different, and this embodiment does not limit this. The protection functions of the corresponding charge and discharge protection circuits 3 may be the same or different, for example, they may be used for overcharge, overdischarge, overcurrent protection of the battery cell 1, etc., and may be set according to actual conditions.

[0062] The controller in this embodiment is used to directly use the secondary charge and discharge protection circuit to work when the primary charge and discharge protection circuit is abnormal. If the secondary charge and discharge protection circuit is abnormal, the software over-discharge protection function in the controller is used to continue to maintain the current operation.

[0063] The controller's INT2 interrupt pin is connected to the secondary charge and discharge protection circuit through a bidirectional two-wire synchronous serial bus (Inter-Integrated Circuit, I2C) line. It can configure the charging voltage and charging current, detect whether there is any abnormal charging situation, and receive abnormal prompts more quickly.

[0064] In some embodiments, Figure 1 As shown, the primary charge and discharge protection circuit 5 at least includes an overcharge protection circuit, a first transistor Q1, a second transistor Q2 and a first charge and discharge chip U1;

[0065] The overcharge protection circuit includes a first resistor R1 and a first capacitor C1, wherein the first end of the first resistor R1 is respectively connected to the first end of the connector 2 and the secondary charge and discharge protection circuit, and the second end of the first resistor R1 is respectively connected to the first end of the first charge and discharge chip U1 and the first end of the first capacitor C1;

[0066] The second end of the first capacitor C1 is respectively connected to the second end of the connector 2 and the second end of the first charging and discharging chip U1;

[0067] The control end of the first transistor Q1 is connected to the third end of the first charge and discharge chip U1; the first end of the first transistor Q1 is connected to the second end of the connector 2; the second end of the first transistor Q1 is connected to the first end of the second transistor Q2;

[0068] The control end of the second transistor Q2 is connected to the fourth end of the first charging and discharging chip U1; the second end of the second transistor Q2 is grounded.

[0069] In this embodiment, the overcharge protection circuit is an auxiliary protection, which is set to prevent the device from having a short circuit fault when charging, causing an impact on the power grid. The general logic is a closing command plus an AND gate composed of an overcurrent relay action contact, plus a short delay. Charging protection is generally used for charging closing of the mother circuit breaker. In this embodiment, the first resistor R1 and the first capacitor C1 are set, and the first charge and discharge chip U1 is to detect the voltage difference between the first end (VDD pin) and the second end (VSS pin) of the chip to determine whether it is higher than the overcharge voltage threshold. If it is higher, it means that overcharging occurs. Therefore, when the battery cell is overcharged, the chip controls the third end (D0 pin) or the fourth end (C0 pin), and the voltage outputs a high level, that is, the control end of the first transistor Q1 or the second transistor Q2 is a high level, not conducting, the system cannot form a loop, and the subsequent circuit does not work.

[0070] In some embodiments, Figure 1 As shown, the primary charge and discharge protection circuit 5 also has over-discharge protection and over-current protection functions, that is, the primary charge and discharge protection circuit 5 also includes an over-discharge protection circuit and an over-current protection circuit;

[0071] The overcurrent protection circuit includes a second resistor R2; the first end of the second resistor R2 is respectively connected to the second end of the connector 2 and the second end of the first charge and discharge chip U1; the second end of the second resistor R2 is respectively connected to the fifth end of the first charge and discharge chip U1 and the first end of the first transistor Q1;

[0072] The over-discharge protection circuit includes a third resistor R3; a first end of the third resistor R3 is connected to the sixth end of the first charge-discharge chip U1, and a second end of the third resistor R3 is connected to the second end of the second transistor Q2 and is grounded.

[0073] Specifically, battery overdischarge means that the battery voltage is lower than the battery's discharge termination voltage. For example, the discharge termination voltage of a lithium battery is 2.4V. Excessive discharge is harmful to the battery and can even cause the battery cell to lose its function and be damaged. Preventing the battery from continuing to discharge after reaching the discharge termination voltage and shutting down the battery output to protect the battery is called overdischarge protection.

[0074] The over-discharge protection circuit is based on the third resistor R3. The first charge and discharge chip U1 detects the voltage difference between the second end (VSS pin) and the fifth end (VM pin) of the chip to determine whether it is lower than the over-discharge voltage threshold. If it is lower, it means that over-discharge has occurred.

[0075] The overcurrent protection circuit is based on a rated current, and it is not allowed to exceed the rated current, otherwise the device will burn out. The overcurrent protection circuit in this embodiment is based on the second resistor R2. The first charge and discharge chip U1 detects the voltage difference between the second end (VSS pin) and the third end (CS pin) of the chip, and calculates the current through the voltage difference and the resistance value of the second resistor R2 to determine whether it is higher than the overcurrent threshold. If it is higher, it indicates overcurrent.

[0076] If the battery cell has abnormal conditions such as over-discharge or over-current, the control end of the first transistor Q1 or the second transistor Q2 outputs a high level, causing the first transistor Q1 or the second transistor Q2 to be non-conductive, the system cannot form a loop, and the subsequent circuit does not work.

[0077] The overcharge, over-discharge and over-current protection circuits provided in this embodiment ensure the normal operation of the battery cell.

[0078] In some embodiments, Figure 1 As shown, the first-level charge and discharge protection circuit also includes a second capacitor C2, a third capacitor C3 and a fourth capacitor C4;

[0079] The first end of the second capacitor C2 is respectively connected to the second end of the second resistor R2, the fifth end of the first charge-discharge chip U1 and the first end of the first transistor Q1; the second end of the second capacitor C2 is connected to the first end of the third capacitor C3;

[0080] A second end of the third capacitor C3 is respectively connected to the second end of the second transistor Q2 and the second end of the third resistor R3, and is grounded;

[0081] A first end of the fourth capacitor C4 is connected to the secondary charge and discharge protection circuit; a second end of the fourth capacitor C4 is grounded.

[0082] Specifically, the second capacitor C2 and the third capacitor C3 are used to absorb the peak current generated during the switching process of the first transistor Q1 and the second transistor Q3 to extend the life of the transistors. The second capacitor C2 and the third capacitor C3 are connected in series and then connected in parallel with the first transistor Q1 and the second transistor Q3. The fourth capacitor C4 is used for filtering.

[0083] The three capacitors provided in this embodiment ensure the normal operation of the first-level charge and discharge protection circuit.

[0084] In some embodiments, further comprising an ESD protection circuit;

[0085] The ESD protection circuit is connected to the battery cell through a connector; the ESD protection circuit is connected to the charge and discharge protection circuit, wherein the ESD protection circuit is a bidirectional TVS tube.

[0086] Specifically, Figure 3 Another circuit diagram of a charging and discharging circuit based on a battery cell provided in an embodiment of the utility model is shown in FIG. Figure 3 As shown, the electrostatic discharge (ESD) protection circuit 8 is composed of a bidirectional TVS tube D1. D1 is placed close to the battery interface of the internal circuit board of the product to absorb the transient spike voltage and current generated during the battery plugging and unplugging process. The use of a bidirectional transient voltage suppressor (TVS) diode avoids the ESD protection failure problem caused by the reverse connection of the positive and negative poles of the battery 1.

[0087] In some embodiments, Figure 3 As shown, it also includes an anti-reverse connection circuit 9, which includes a fifth capacitor C5, a sixth capacitor C6, a third transistor Q3, a fourth transistor Q4, a fourth resistor R4 and a fifth resistor R5, wherein the third transistor Q3 is a positive channel Metal Oxide Semiconductor (PMOS) tube, and the fourth transistor Q4 is an N-type Metal Oxide Semiconductor (NMOS) tube;

[0088] The control end of the third transistor Q3 is respectively connected to the second end of the connector 2 and the second end of the fourth transistor Q4, the first end of the third transistor Q3 is connected to the first end of the connector 2, and the second end of the third transistor Q3 is connected to the control end of the fourth transistor Q4;

[0089] The first end of the fourth transistor Q4 is connected to the charge and discharge protection circuit; the first end of the fifth capacitor C5 is respectively connected to the first end of the connector 2 and the first end of the third transistor Q3; the second end of the fifth capacitor C5 is respectively connected to the second end of the third transistor Q3 and the control end of the fourth transistor Q4;

[0090] The first end of the sixth capacitor C6 is respectively connected to the control end of the third transistor Q3 and the second end of the fourth transistor Q4; the second end of the sixth capacitor C6 is respectively connected to the first end of the fourth transistor Q4 and the charge and discharge protection circuit;

[0091] A first end of the fourth resistor R4 is connected to a first end of the third transistor Q3, and a second end of the fourth resistor R4 is connected to a second end of the fourth transistor Q4;

[0092] A first end of the fifth resistor R5 is connected to the second end of the third transistor Q3 , and a second end of the fifth resistor R5 is connected to the first end of the fourth transistor Q4 .

[0093] Specifically, if the positive and negative poles of the battery cell 1 are connected correctly, the voltage at the control end of the third triode Q3 is lower than the voltage at the first end, and the third triode Q3 is turned on, and the voltage at the control end of the fourth triode Q4 is higher than the voltage at the first end, and the fourth triode Q4 is turned on, and the output voltage is normal. If the positive and negative poles of the battery cell 1 are reversely connected, the third triode Q3 is not turned on, and the fourth triode Q4 is not turned on due to the presence of the fifth resistor R5, the battery cell 1 and the subsequent circuit do not form a loop, and the system does not work.

[0094] The fourth resistor R4 and the fifth resistor R5 are used to maintain the level state. The fifth capacitor C5 and the sixth capacitor C6 can absorb the peak current generated during the switching process of the third transistor Q3 and the fourth transistor Q4, thereby extending the life of the transistors.

[0095] In some embodiments, Figure 1 and Figure 3 As shown, it also includes a power detection module 6;

[0096] The electric quantity detection module 6 is connected to the charge and discharge protection circuit 3 and to the controller 4 .

[0097] Specifically, the power detection module 6 collects the voltage value of Li_Power, matches the power discharge curve of the battery cell 1, and timely feeds back the power information of the battery cell 1 to avoid the battery cell 1 from being used with insufficient power. The controller 4 is connected to the power detection module 6, and reads the power of the battery cell 1 in real time through I2C communication. If it is detected that the power of the battery cell 1 is close to the control level, the software controls the subsequent circuit to disconnect, and adds software over-discharge protection, that is, the software protection mentioned in the above embodiment, so that the service life of the battery cell 1 is longer.

[0098] In addition, the INT1 interrupt pin of the controller 4 is connected to the power detection module so that it can receive abnormal prompts more quickly.

[0099] In some embodiments, Figure 1 and Figure 3 As shown, it also includes a temperature detection circuit 7;

[0100] The temperature detection circuit 7 is connected to the electric quantity detection module 6 and to the charge and discharge protection circuit 3 , wherein the temperature detection circuit 7 is a thermistor.

[0101] Specifically, the temperature detection circuit 7 is a thermistor (RT1 and RT2), which can detect the temperature of the battery compartment. When the temperature and the resistance value of the resistor are negatively correlated, the resistance value is matched with the voltage value, so that after the abnormality is found, the secondary charge and discharge protection circuit of the charge and discharge protection circuit 3 automatically cuts off the charging path, notifies the controller 4 of the abnormality, and the controller 4 can identify the abnormality and make corresponding processing. In this embodiment, it is also connected to the power detection module, and the voltage value is detected by the power detection module and the secondary charge and discharge protection circuit of the charge and discharge protection circuit. If the voltage value is outside the safe range, the abnormality can be directly notified to the controller 4 through the I2C line.

[0102] In some embodiments, Figure 3 As shown, it also includes an energy storage module 10, wherein the energy storage module 10 includes a seventh capacitor C7 and an eighth capacitor C8;

[0103] The seventh capacitor C7 and the eighth capacitor C8 are both connected to the connector 3 and to the charge and discharge protection circuit 3 .

[0104] Specifically, the seventh capacitor C7 and the eighth capacitor C8 play an energy storage role. The types of energy storage capacitors include ceramic capacitors, tantalum capacitors, electrolytic capacitors, etc. The capacitance value is determined according to the system power consumption and the risk power-off time. The energy storage capacitor capacity is calculated by the formula E=1 / 2*C*U2, where C is the capacitance value of the seventh capacitor C7 and the eighth capacitor C8, and U is the voltage value of the battery cell.

[0105] On the basis of the above-mentioned embodiments, the utility model further provides a battery compartment, including a battery cell and the above-mentioned charging and discharging circuit based on the battery cell.

[0106] like Figure 2 As shown, the battery cell can use models of various standard specifications and sizes, such as 18650, CR123, etc. The battery cell 1 is fixed in a battery compartment 13 composed of a battery cell positive electrode spring sheet 11, a battery cell negative electrode spring plate 12, and a structural member (based on the charging and discharging circuit of the battery cell). Due to the tensile ductility of the negative electrode spring, it is easy to disassemble and install the battery cell 1, and it is easy to replace a new battery after the battery cell 1 ages. The battery cell positive electrode spring sheet 11 is made of a metal material with good thermal conductivity, which is convenient for conducting the heat of the battery cell 1 to the temperature detection circuit 7 through the battery positive electrode spring sheet 11. The temperature detection circuit 7 and the battery cell positive electrode spring sheet 11 are fixed with 3M glue, which can withstand high and low temperature environments and can accurately sense the temperature of the battery cell 1. A connector 2 is left on the temperature detection circuit 7, which is connected to the internal circuit board of the product through a connecting line, and the sensed temperature information is transmitted to the power detection module and the charging + charging and discharging secondary protection module on the internal circuit board. The positive spring sheet 11 of the battery cell and the negative spring plate 12 of the battery are connected to the internal circuit board of the product through welding points for powering the system.

[0107] The above is a detailed introduction to a cell-based charging and discharging circuit and a battery compartment provided by the utility model. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be referenced to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the utility model.

[0108] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A charging and discharging circuit based on a battery cell, characterized in that: The charging and discharging circuit comprises a connector (2), a charging and discharging protection circuit (3) and a controller (4); The connector (2) is used to connect the battery cell (1) and the charge and discharge protection circuit (3), wherein the battery cell (1) is separated from the protection board and is located above the protection board, and the charge and discharge protection circuit (3) is located on the protection board; The charge and discharge protection circuit (3) is connected to the controller (4); The controller (4) is used to perform charge and discharge protection on the battery cell (1) through software protection when the charge and discharge protection circuit (3) is abnormal.

2. The charging and discharging circuit based on the battery cell according to claim 1, characterized in that: The charge and discharge protection circuit (3) comprises a primary charge and discharge protection circuit (5) and a secondary charge and discharge protection circuit; The primary charge and discharge protection circuit (5) is connected to the connector (2) and the secondary charge and discharge protection circuit respectively; The secondary charge and discharge protection circuit is connected to the controller (4).

3. The charging and discharging circuit based on the battery cell according to claim 2, characterized in that: The primary charge and discharge protection circuit (5) comprises at least an overcharge protection circuit, a first triode, a second triode and a first charge and discharge chip; The overcharge protection circuit comprises a first resistor and a first capacitor, wherein the first end of the first resistor is respectively connected to the first end of the connector (2) and the secondary charge and discharge protection circuit, and the second end of the first resistor is respectively connected to the first end of the first charge and discharge chip and the first end of the first capacitor; The second end of the first capacitor is respectively connected to the second end of the connector (2) and the second end of the first charge-discharge chip; The control end of the first transistor is connected to the third end of the first charge and discharge chip; the first end of the first transistor is connected to the second end of the connector (2); the second end of the first transistor is connected to the first end of the second transistor; The control end of the second transistor is connected to the fourth end of the first charge and discharge chip; the second end of the second transistor is grounded.

4. The cell-based charging and discharging circuit according to claim 3, characterized in that: The primary charge and discharge protection circuit (5) further comprises an over-discharge protection circuit and an over-current protection circuit; The overcurrent protection circuit comprises a second resistor; the first end of the second resistor is respectively connected to the second end of the connector (2) and the second end of the first charge-discharge chip; the second end of the second resistor is respectively connected to the fifth end of the first charge-discharge chip and the first end of the first transistor; The over-discharge protection circuit includes a third resistor; a first end of the third resistor is connected to the sixth end of the first charge and discharge chip, and a second end of the third resistor is connected to the second end of the second transistor and is grounded.

5. The charge and discharge circuit based on the battery cell according to claim 4, characterized in that: The first-level charge and discharge protection circuit also includes a second capacitor, a third capacitor and a fourth capacitor; The first end of the second capacitor is respectively connected to the second end of the second resistor, the fifth end of the first charge-discharge chip and the first end of the first transistor; the second end of the second capacitor is connected to the first end of the third capacitor; The second end of the third capacitor is respectively connected to the second end of the second transistor and the second end of the third resistor, and is grounded; The first end of the fourth capacitor is connected to the secondary charge and discharge protection circuit; the second end of the fourth capacitor is grounded.

6. The charging and discharging circuit based on a battery cell according to any one of claims 1 to 5, characterized in that: Also includes an ESD protection circuit (8); The ESD protection circuit (8) is connected to the connector (2) and the charge and discharge protection circuit (3) respectively, wherein the ESD protection circuit (8) is a bidirectional TVS tube.

7. The cell-based charging and discharging circuit according to claim 6, characterized in that: It also includes an anti-reverse connection circuit (9), the anti-reverse connection circuit (9) including a fifth capacitor, a sixth capacitor, a third transistor, a fourth transistor, a fourth resistor and a fifth resistor, wherein the third transistor is a PMOS transistor and the fourth transistor is an NMOS transistor; The control end of the third transistor is respectively connected to the second end of the connector (2) and the second end of the fourth transistor, the first end of the third transistor is connected to the first end of the connector (2), and the second end of the third transistor is connected to the control end of the fourth transistor; The first end of the fourth transistor is connected to the charge and discharge protection circuit (3); the first end of the fifth capacitor is respectively connected to the first end of the connector (2) and the first end of the third transistor; the second end of the fifth capacitor is respectively connected to the second end of the third transistor and the control end of the fourth transistor; The first end of the sixth capacitor is respectively connected to the control end of the third transistor and the second end of the fourth transistor; the second end of the sixth capacitor is respectively connected to the first end of the fourth transistor and the charge and discharge protection circuit (3); The first end of the fourth resistor is connected to the first end of the third transistor, and the second end of the fourth resistor is connected to the second end of the fourth transistor; The first end of the fifth resistor is connected to the second end of the third transistor, and the second end of the fifth resistor is connected to the first end of the fourth transistor.

8. The charge and discharge circuit based on the battery cell according to claim 6, characterized in that: It also includes a power detection module (6); The electric quantity detection module (6) is connected to the charge and discharge protection circuit (3) and the controller (4) respectively.

9. The charging and discharging circuit based on the battery cell according to claim 8, characterized in that: Also includes a temperature detection circuit (7); The temperature detection circuit (7) is connected to the power detection module (6) and the charge and discharge protection circuit (3) respectively, wherein the temperature detection circuit (7) is a thermistor.

10. A battery compartment, characterized in that: It comprises a battery cell (1) and a charging and discharging circuit based on the battery cell as claimed in any one of claims 1 to 9.

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