Lithium battery control circuit and camera battery compartment

Abstract

The present application relates to a lithium battery control circuit and a camera battery compartment, wherein the control circuit comprises a first protection unit and a second protection unit, wherein the positive power input port of the first protection unit is electrically connected to the positive port, the positive power input port of the second protection unit and the positive pole of the first battery cell unit, the secondary input port of the first protection unit is electrically connected to the secondary input port of the second protection unit and the negative pole of the first battery cell unit, the negative power input port of the first protection unit is electrically connected to the negative pole of the second battery cell unit, the first protection unit controls the electrical connection of the first charging switch and the first discharging switch, the negative pole of the second battery cell unit is also electrically connected to the second discharging switch through the first charging switch and the first discharging switch, the second protection unit controls the electrical connection of the second charging switch and the second discharging switch, the end of the second charging switch away from the electrical connection with the second discharging switch is electrically connected to the negative port, and an output protection circuit is provided between the positive port and the negative port.

Description

Technical Field

[0001] The present application relates to the field of lithium battery technology, and in particular to a lithium battery control circuit and a camera battery compartment. Background Art

[0002] In the field of new energy batteries, multiple batteries are often connected in parallel to form corresponding battery cells, and then the multiple battery cells are connected in series to form corresponding battery packs, thereby meeting the power supply needs of large capacity and large current.

[0003] In the prior art, for a battery pack composed of battery cells connected in series, a corresponding control circuit is set to protect all individual battery cells and the entire battery pack. For example, by monitoring the voltage and current of all individual battery cells during charging and discharging, when overcharging or over-discharging occurs, the corresponding circuit is disconnected to suspend the battery pack from continuing to overcharge or over-discharge. However, in the related art, the protection of the battery pack connected in series has the defect that the battery pack cannot always be protected. That is, when the corresponding protection circuit fails or is disconnected from the battery pack, the battery pack is not protected, resulting in damage to the battery pack and the risk of battery explosion.

[0004] There is still a lack of better technical solutions to the problem that the battery pack in the related art cannot always maintain a protected state and is prone to damage to the battery pack. Summary of the invention

[0005] The present application provides a lithium battery control circuit and a camera battery compartment to at least solve the problem in the related art that the battery pack cannot always maintain a protected state and is prone to damage to the battery pack.

[0006] In the first aspect, the present application provides a lithium battery control circuit, including a first protection unit and a second protection unit, the positive power input port of the first protection unit is electrically connected to the positive port, the positive power input port of the second protection unit and the positive electrode of the first battery cell unit, the secondary input port of the first protection unit is electrically connected to the secondary input port of the second protection unit and the electrical connection point between the first battery cell unit and the second battery cell unit, the negative power input port of the first protection unit is electrically connected to the negative electrode of the second battery cell unit, the first protection unit controls a first charging switch and a first discharging switch electrically connected in series, the negative electrode of the second battery cell unit is also electrically connected to the second discharging switch through the first charging switch and the first discharging switch, and the second protection unit controls the second charging switch and the second discharging switch electrically connected in series. An electrical switch, an end of the second charging switch away from the end electrically connected to the second discharging switch is electrically connected to the negative port, and an output protection circuit is also coupled and electrically connected between the positive port and the negative port, wherein the first protection unit is used to control the on and off of the first charging switch and / or the first discharging switch to protect the charging and discharging of the battery pack, wherein the battery pack is composed of the first battery cell unit and the second battery cell unit connected in series; the second protection unit is used to control the on and off of the second charging switch and / or the second discharging switch to protect the charging and discharging of the battery pack; the first protection unit and the second protection unit are also configured to maintain protection for the battery pack at least one of them; the output protection circuit is used to control the positive electrode of the first battery cell unit to be disconnected from the positive port when the output of the battery pack is abnormal.

[0007] In some embodiments, the first protection unit includes a first control unit and a first RC filter circuit, the first port of the first control unit is electrically connected to the positive power input port of the first protection unit through the first RC filter circuit, the second port of the first control unit is electrically connected to the secondary input port of the first protection unit through the first RC filter circuit, the third port of the first control unit is connected to the negative power input port of the first protection unit, the charge and discharge detection port of the first control unit is electrically connected to the input end of the first discharge switch through a first coupling resistor in series, the discharge control port of the first control unit is electrically connected to the controlled end of the first discharge switch through a second coupling resistor in series, the charge control port of the first control unit is electrically connected to the controlled end of the first charge switch, the first discharge switch is electrically connected to the output end of the first charge switch, and is electrically connected to the negative power input port of the first protection unit through a third coupling resistor, and the load detection port of the first control unit is also electrically connected to the electrical connection point of the first charge switch and the second discharge switch through a fourth coupling resistor in series, wherein,

[0008] The first control unit is used to determine whether the battery pack is charged and discharged normally by detecting the voltage of the first battery cell unit and the second battery cell unit, and detecting the voltage between the negative power input port and the load detection port thereof, wherein the voltage of the first battery cell unit and the second battery cell unit is determined by detecting the voltage of the positive power input port, the secondary input port and the negative power input port of the first control unit;

[0009] The first control unit is further used to control the first discharge switch to be disconnected when it is determined that the battery pack is over-discharged, the first control unit is further used to control the first charge switch to be disconnected when it is determined that the battery pack is over-charged, and the first control unit controls the first discharge switch and the first charge switch to be disconnected when it is detected that at least one of the first battery cell unit and the first battery cell unit is disconnected.

[0010] In some embodiments, the first control unit includes a battery protection chip of model CM1022-CA, and / or the first RC filter circuit includes an L-type RC filter circuit composed of a first resistor and a first capacitor.

[0011] In some embodiments, the first protection unit also includes a temperature protection circuit, which includes a second resistor and a first temperature sensor connected in series, the electrical connection point between the second resistor and the first temperature sensor is electrically connected to the temperature protection detection port of the first control unit, the end of the second resistor away from the electrical connection with the first temperature sensor is electrically connected to the temperature protection reference port of the first control unit, and the end of the first temperature sensor away from the electrical connection with the second resistor is electrically connected to the negative power input port of the first control unit, wherein the first temperature sensor is used to detect the temperature of the battery pack during charging and discharging and generate a corresponding first voltage signal; the first control unit is used to control the first charging switch and the first discharging switch to be disconnected when the first voltage signal received at its temperature protection reference port is greater than a preset temperature protection reference voltage.

[0012] In some embodiments, the second protection unit includes a second control unit and a second RC filter circuit, the first port of the second control unit is electrically connected to the positive power input port of the second protection unit through the second RC filter circuit, the second port of the second control unit is electrically connected to the secondary input port of the second protection unit through the second RC filter circuit, the third port of the second control unit is connected to the negative power input port of the second protection unit, the discharge control port of the second control unit is electrically connected to the controlled end of the second discharge switch, the charge control port of the second control unit is electrically connected to the controlled end of the second charge switch, the output end of the second discharge switch and the second charge switch are electrically connected, and the second control unit The overcharge and discharge detection port of the element is also electrically connected to the input end of the second charging switch through a fifth coupling resistor in series, wherein the second control unit is used to determine whether the battery pack is charged and discharged normally by detecting the voltage of the first battery cell and the second battery cell, and detecting the voltage between its negative power input port and the overcharge and discharge detection port, wherein the voltage of the first battery cell and the second battery cell is determined by detecting the voltage of the positive power input port, the secondary input port and the negative power input port of the second control unit; the second control unit is also used to control the second discharge switch to be disconnected when it is determined that the battery pack is over-discharged, and the second control unit is also used to control the second charging switch to be disconnected when it is determined that the battery pack is overcharged.

[0013] In some embodiments, the second control unit includes a battery protection chip of model SIT8252C, and / or the second RC filter circuit includes an L-type RC filter circuit composed of a second resistor and a second capacitor.

[0014] In some embodiments, the electrical connection point between the input end of the second charging switch and the negative port is also electrically connected to a second temperature sensor, and the other end of the second temperature sensor is electrically connected to an external power terminal, wherein the second temperature sensor is used to detect the temperature of the battery pack during charging and discharging, and transmit the detected temperature signal to the external power terminal, so that the external power terminal controls the second control unit to perform charging and discharging control according to the received temperature signal; the output protection circuit includes a fuse, a third capacitor and a fourth capacitor, the fuse is connected in series between the positive electrode of the first battery cell unit and the positive port, one end of the third capacitor is electrically connected to the fuse and the positive port, and the other end is electrically connected to the fourth capacitor, and the end of the fourth capacitor away from the electrical connection with the third capacitor is electrically connected to the negative port.

[0015] In some embodiments, the first charging switch, the first discharging switch, the second charging switch and the second discharging switch all include a switch tube, and the switch tube includes a control end, an input end and an output end. The control end corresponding to the first discharging switch is connected to the controlled end of the first discharging switch, the input end corresponding to the first discharging switch is connected to the input end of the first discharging switch, the output end corresponding to the first discharging switch is connected to the output end of the first discharging switch, the control end corresponding to the first charging switch is connected to the controlled end of the first charging switch, the input end corresponding to the first charging switch is connected to the input end of the first charging switch, the output end corresponding to the first charging switch is connected to the output end of the first charging switch, the control end corresponding to the second discharging switch is connected to the controlled end of the second discharging switch, the input end corresponding to the second discharging switch is connected to the input end of the second discharging switch, and the output end corresponding to the second discharging switch is connected to the output end of the first discharging switch. The output end is connected to the output end of the second discharge switch, the control end corresponding to the second charging switch is connected to the controlled end of the second charging switch, the input end corresponding to the second charging switch is connected to the input end of the second charging switch, and the output end corresponding to the second charging switch is connected to the output end of the second charging switch, wherein the switch tube is used to control the on and off of the input end and the output end according to the enable signal received by the control end; when the input end and the output end of the switch tube corresponding to the first discharge switch are disconnected, the first discharge switch is disconnected, when the input end and the output end of the switch tube corresponding to the first charging switch are disconnected, the first charging switch is disconnected, when the input end and the output end of the switch tube corresponding to the second discharge switch are disconnected, the second discharge switch is disconnected, and when the input end and the output end of the switch tube corresponding to the second charging switch are disconnected, the second charging switch is disconnected.

[0016] In some embodiments, a first disconnect switch is provided between the negative power input port of the first protection unit and the second discharge switch, and a second disconnect switch is provided between the negative power input port and the negative port of the second protection unit, wherein when the first disconnect switch is closed, the first protection unit is disconnected from the battery pack; when the second disconnect switch is closed, the second protection unit is disconnected from the battery pack; when one of the first protection unit and the second protection unit is disconnected from the battery pack, the other of the first protection unit and the second protection unit continues to protect the battery pack

[0017] In a second aspect, the present application provides a power camera battery compartment, comprising a compartment box, a control board disposed in the compartment box, a battery pack disposed in the compartment box, and a cover plate covering the compartment box, wherein the battery pack is also electrically connected to the control board, and a control circuit for controlling the charging and discharging of the battery pack is provided on the control board, wherein the control circuit is the lithium battery control circuit described in the first aspect.

[0018] Compared with the related art, the present embodiment provides a lithium battery control circuit and a camera battery compartment, the lithium battery control circuit includes a first protection unit and a second protection unit, the positive power input port of the first protection unit is electrically connected to the positive port, the positive power input port of the second protection unit and the positive electrode of the first battery cell unit respectively, the secondary input port of the first protection unit is electrically connected to the secondary input port of the second protection unit and the electrical connection point between the first battery cell unit and the second battery cell unit respectively, the negative power input port of the first protection unit is electrically connected to the negative electrode of the second battery cell unit, the first protection unit controls the first charging switch and the first discharging switch electrically connected in series, the negative electrode of the second battery cell unit is also electrically connected to the second discharging switch through the first charging switch and the first discharging switch, the second protection unit controls the second charging switch and the second discharging switch electrically connected in series, the end of the second charging switch away from the electrical connection with the second discharging switch is electrically connected to the negative port, the positive port and the negative port are also coupled to an output protection circuit electrically connected, wherein, The first protection unit is used to control the on and off of the first charging switch and / or the first discharging switch to protect the charging and discharging of the battery pack, wherein the battery pack is composed of the first battery cell unit and the second battery cell unit connected in series; the second protection unit is used to control the on and off of the second charging switch and / or the second discharging switch to protect the charging and discharging of the battery pack; the first protection unit and the second protection unit are also configured so that at least one of them maintains protection for the battery pack; the output protection circuit is used to control the positive electrode of the first battery cell unit to be disconnected from the positive port when the output of the battery pack is abnormal, and to protect the battery pack using two protection units, thereby ensuring that at least one protection unit maintains protection for the battery pack. At the same time, the coordinated protection of the two protection units can ensure that during the overcharging and discharging process of the battery pack, the charging state or discharging state of the battery pack can be accurately detected and the charging and discharging of the battery pack can be accurately controlled, thereby improving the service life of the battery pack and solving the problem in the related art that the battery pack cannot always maintain a protected state and is prone to damage to the battery pack.

[0019] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 A structural block diagram of a lithium battery control circuit provided in an embodiment of the present application;

[0023] Figure 2 A topological structure diagram of a lithium battery control circuit according to an embodiment of the present application;

[0024] Figure 3 This is a structural block diagram of a lithium battery control circuit according to a preferred embodiment of the present application;

[0025] Figure 4 This is a structural block diagram of a lithium battery control circuit in another preferred embodiment of the present application;

[0026] Figure 5 This is a topological diagram of a lithium battery control circuit of a preferred embodiment of the present application;

[0027] Figure 6 This is a three-dimensional structural diagram of a camera battery compartment according to an embodiment of the present application;

[0028] Figure 7 for Figure 6 A decomposition diagram of . DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0030] The lithium battery control circuit of the present application will be described below in conjunction with the drawings in the embodiments of the present application and through specific embodiments.

[0031] Figure 1 This is a structural block diagram of a lithium battery control circuit provided in an embodiment of the present application. Figure 1As shown, the embodiment of the present application provides a lithium battery control circuit for controlling a battery pack consisting of a first battery cell unit 001 connected in series with a second battery cell unit 002, including a first protection unit 100 and a second protection unit 200, wherein the positive power input port 101 of the first protection unit 100 is electrically connected to the positive port P+, the positive power input port 201 of the second protection unit 200, and the positive electrode of the first battery cell unit 001, respectively, and the secondary input port 102 of the first protection unit 100 is electrically connected to the secondary input port 202 of the second protection unit 200 and the electrical connection point between the first battery cell unit 001 and the second battery cell unit 002 (corresponding to the negative electrode of the first battery cell unit 001 and the second battery cell unit 002, respectively). The first protection unit 100 controls the first charging switch 300 and the first discharging switch 400 which are electrically connected in series, and the negative electrode of the second battery cell 002 is also electrically connected to the second discharging switch 500 through the first charging switch 300 and the first discharging switch 400. The second protection unit 200 controls the second charging switch 600 and the second discharging switch 500 which are electrically connected in series, and the end of the second charging switch 600 which is away from the end electrically connected to the second discharging switch 500 is electrically connected to the negative port P-, and the positive port P+ and the negative port P- are also coupled and electrically connected to the output protection circuit 700, wherein,

[0032] The first protection unit 100 is used to control the on and off of the first charging switch 300 and / or the first discharging switch 400 to protect the charging and discharging of the battery pack, wherein the battery pack is composed of a first battery cell unit 001 and a second battery cell unit 001 connected in series;

[0033] The second protection unit 200 is used to control the on and off of the second charging switch 600 and / or the second discharging switch 500 to protect the charging and discharging of the battery pack;

[0034] The first protection unit 100 and the second protection unit 200 are also configured such that at least one of them maintains protection for the battery pack;

[0035] The output protection circuit 700 is used to control the positive electrode of the first battery cell unit 001 to be disconnected from the positive port P+ when the output of the battery pack is abnormal.

[0036] In this embodiment, during the normal charging and discharging process of the battery pack, the first protection unit 100 and the second protection unit 200 work simultaneously, and the first protection unit 100 continuously detects the voltage of the first battery cell 001 and the second battery cell 002, and detects the voltage of the load detection port at the same time to control charging and discharging. When the voltages of the first battery cell 001 and the second battery cell 002 are both greater than the over-discharge protection voltage and less than the over-charge protection voltage, and the voltage of the load detection port is greater than the charge over-current protection voltage and less than the discharge over-current protection voltage, the first charging switch 300 and the first discharging switch 400 are both enabled. In the closed conduction state, the battery pack can be charged and discharged normally; when the voltage of any one of the first battery cell 001 and the second battery cell 002 is greater than the overcharge protection voltage and the overcharge time exceeds the overcharge detection delay time, or the voltage of the load detection port is less than the charge overcurrent protection voltage and the duration exceeds the charge overcurrent protection delay time, the first charging switch 300 is disconnected to control the battery pack to stop charging; when the voltage of any one of the first battery cell 001 and the second battery cell 002 is lower than the overdischarge protection voltage and the overdischarge time exceeds the overdischarge detection delay time, or the load detection port When the voltage of the overcharge detection port exceeds the discharge overcurrent protection voltage and lasts longer than the discharge overcurrent protection delay time, the first discharge switch 400 is disconnected to control the battery pack to stop discharging; at the same time, the second protection unit 200 continuously detects the voltage of the first battery cell 001 and the second battery cell 002, and detects the voltage difference between the overcharge and discharge detection port and the ground to control the charging and discharging of the battery pack. When the voltage of the first battery cell 001 and the second battery cell 002 are both greater than the overdischarge detection voltage and less than the overcharge detection voltage, and the voltage of the overcharge and discharge detection port is greater than the charge overcurrent detection voltage and less than the discharge overcurrent detection voltage, the overcharge and discharge detection port is charged. When the current detection voltage is detected, the second charging switch 600 and the second discharging switch 500 are both enabled to be in a closed conduction state, and the battery pack can be charged and discharged normally; it can be understood that when one of the first protection unit 100 and the second protection unit 200 is in an isolated state from the battery pack, or one of the protection units continuously detects the voltage corresponding to the battery pack, and an error occurs in the detected voltage and / or voltage difference, resulting in the inability to accurately control the stop of charging or discharging, the other protection unit is used for charging and discharging protection, so that the battery pack is always in a protected state to avoid damage to the battery pack.

[0037] In this embodiment, an output protection circuit is provided between the positive port P+ and the negative port P- of the battery pack. When the output of the battery pack is abnormal (for example, overcurrent caused by a short circuit, overvoltage charging and discharging of the battery pack) and charging is impossible or discharging is not stopped under control, the positive electrode of the battery pack (corresponding to the positive electrode of the first battery cell unit 001) is disconnected from the positive port P+ through the output protection circuit 700, thereby stopping the battery pack from charging or discharging, thereby further protecting the battery pack.

[0038] The above-mentioned lithium battery control circuit adopts the first protection unit 100 and the second protection unit 200 to be set as at least one of them to maintain the protection of the battery pack, and controls the on and off of the first charging switch 400 and / or the first discharging switch 300 through the first protection unit 100, and controls the on and off of the second charging switch 600 and / or the second discharging switch 500 through the second protection unit 200, so as to protect the charging and discharging of the battery pack; and also sets an output protection circuit 700 to control the positive pole of the first battery cell unit 001 to be disconnected from the positive port when the output of the battery pack is abnormal, and adopts two-way protection units to protect the battery pack, thereby ensuring that at least one protection unit maintains the protection of the battery pack. At the same time, the two-way protection units cooperate to protect, so as to ensure that during the overcharging and discharging process of the battery pack, the charging state or discharging state of the battery pack can be accurately detected and the charging and discharging of the battery pack can be accurately controlled, thereby improving the service life of the battery pack and solving the problem that the battery pack in the related art cannot always maintain the protected state and is easy to cause damage to the battery pack.

[0039] Figure 2 This is a topological structure diagram of the lithium battery control circuit of the embodiment of the present application. In order to protect the charging and discharging of the battery pack, refer to Figure 1 to Figure 2 In some embodiments, the first protection unit 100 includes a first control unit 11 and a first RC filter circuit 12, the first port of the first control unit 11 (reference Figure 2 VC1 pin of U1) through the first RC filter circuit 12 (reference Figure 2 The L-type RC filter circuit composed of the resistor R1 and the capacitor C1 in the first protection unit 100 is electrically connected to the positive power input port 101 (also refer to Figure 2 B+ in the first control unit 11, the second port (reference Figure 2 VC2 pin of U1 in the middle) through a first RC filter circuit 12 (reference Figure 2 The L-type RC filter circuit composed of the resistor R2 and the capacitor C2 in the first protection unit 11 is electrically connected to the secondary input port 102 (also refer to Figure 2 BM in), the third port of the first control unit 11 (reference Figure 2 The VSS pin of U1 in the figure) is connected to the negative power input port 103 of the first protection unit 100 (also refer to Figure 2 B-), the charge and discharge detection port of the first control unit 11 (reference Figure 2 The VIN pin of U1 in the figure is connected in series with the input end of the first discharge switch 400 (reference Figure 2 The S end of Q1 in the middle is electrically connected to the discharge control port of the first control unit 11 (reference Figure 2The D0 pin of U1 in the middle) is connected in series with the controlled end (reference Figure 2 The G end of Q1 in the middle is electrically connected to the charging control port of the first control unit 11 (reference Figure 2 The CO pin of U1 in the circuit) is connected to the controlled terminal of the first charging switch 300 (reference Figure 2 The output terminal of the first discharge switch 400 and the output terminal of the first charge switch 300 (reference Figure 2 The D end of Q1 and Q2 in the middle is electrically connected, and connected to the negative power input port 103 (reference Figure 2 B-) is electrically connected to the load detection port of the first control unit 11 (reference Figure 2 The VM pin of U1 in FIG. 1 is also electrically connected to the electrical connection point of the first charging switch 300 and the second discharging switch 500 through a fourth coupling resistor R6 in series, wherein:

[0040] The first control unit 11 is used to detect the voltage of the first battery cell 001 and the second battery cell 002, and detect the negative power input port 103 and the load detection port (refer to Figure 2 The voltage between the VM pin of U1 in the control unit 11 is measured to determine whether the battery pack is charged and discharged normally, wherein the voltage of the first battery cell unit 001 and the second battery cell unit 002 is determined by detecting the voltage of the positive power input port 101, the secondary input port 102 and the negative power input port 103 of the first control unit 11;

[0041] The first control unit 11 is further used to control the first discharge switch 400 to be disconnected when it is determined that the battery pack is over-discharged. The first control unit is also used to control the first charge switch 300 to be disconnected when it is determined that the battery pack is over-charged. The first control unit 11 controls the first discharge switch 400 and the first charge switch 300 to be disconnected when it is detected that at least one of the first battery cell 001 and the first battery cell 002 is disconnected.

[0042] It can be understood that in this embodiment, overcharge includes overcharge state and charge overcurrent state, overdischarge includes overdischarge state and discharge overcurrent state, the overcharge state is determined by detecting the voltage of the first battery cell 001 and the second battery cell 002 and the magnitude of the overcharge protection voltage, the overdischarge state is determined by detecting the voltage of the first battery cell 001 and the second battery cell 002 and the magnitude of the overdischarge protection voltage, and the charge overcurrent state is determined by detecting the negative power input port 103 and the load detection port (reference Figure 2 The voltage between the VM pin of U1 in the figure is determined by the size of the charging overcurrent protection voltage. The discharge overcurrent state is determined by detecting the negative power input port 103 and the load detection port (reference Figure 2The voltage between the VM pin of U1 and the discharge overcurrent protection voltage is determined by the voltage between the VM pin of U1 and the discharge overcurrent protection voltage.

[0043] In some optional embodiments, the first control unit 11 includes but is not limited to a battery protection chip U1 of model CM1022-CA; the first RC filter circuit 12 includes a first resistor (reference Figure 2 R1 and R2 in the reference Figure 2 The L-type RC filter circuit is composed of C1 and C2 in the figure.

[0044] In this embodiment, the first control unit 11 cooperates with the corresponding first RC filter circuit 12 to continuously perform voltage detection on the first battery cell 001 and the second battery cell 002. Figure 3 The battery protection chip U1 corresponding to the first control unit 11 performs voltage detection on the first battery cell 001 through pins VC1 and VC2, performs voltage detection on the second battery cell 002 through pins VC2 and VSS, and detects the voltage between the negative power input port 103 and the load detection port through pins VM and VSS.

[0045] Figure 3 This is a structural block diagram of the lithium battery control circuit of the preferred embodiment of the present application. In order to ensure that the battery pack will not be damaged by excessively high or low temperature during the charging and discharging process of the battery pack, refer to Figures 2 to 3 In some optional implementations, the first protection unit 100 further includes a temperature protection circuit 13, the temperature protection circuit 13 includes a second resistor R9 and a first temperature sensor NTC in series, and the electrical connection point between the second resistor R9 and the first temperature sensor NTC is connected to the temperature protection detection port of the first control unit 11 (reference Figure 2 The end of the second resistor R9 away from the end electrically connected to the first temperature sensor NTC is connected to the temperature protection reference port (reference port) of the first control unit 11. Figure 2 The first temperature sensor NTC is electrically connected to the RTV pin of U1, and the end thereof away from the end electrically connected to the second resistor R9 is electrically connected to the negative power input port of the first control unit 11 (reference Figure 2 B-) electrical connection, wherein,

[0046] The first temperature sensor NTC is used to detect the temperature of the battery pack during charging and discharging, and generate a corresponding first voltage signal;

[0047] The first control unit 11 is used to protect the reference port (reference Figure 2 When the first voltage signal received by the RTV pin of U1 is greater than the preset temperature protection reference voltage, the first charging switch 300 and the first discharging switch 400 are controlled to be disconnected.

[0048] To further protect the battery pack from charge and discharge, refer to Figure 1 to Figure 2 In some embodiments, the second protection unit 200 includes a second control unit 21 and a second RC filter circuit 22, the first port of the second control unit 21 (reference Figure 2 The VDD pin of U2 in the circuit) passes through a second RC filter circuit 22 (reference Figure 2 The L-type RC filter circuit composed of the resistor R7 and the capacitor C3 in the second protection unit 200 is electrically connected to the positive power input port 201 (also refer to Figure 2 B+ in the second control unit 21), the second port (reference Figure 2 BI pin of U2) through a second RC filter circuit 22 (reference Figure 2 The L-type RC filter circuit composed of the resistor R8 and the capacitor C4 in the protection unit 200 is electrically connected to the secondary input port 202 of the second protection unit 200 (also refer to Figure 2 BM in), the third port of the second control unit 21 (reference Figure 2 The B-pin of U2 in the middle) is connected to the negative power input port 203 of the second protection unit 200, and the discharge control port of the second control unit 21 (reference Figure 2 OD pin of U2 in the middle) and the controlled end of the second discharge switch 500 (reference Figure 2 The G end of Q3 in the middle is electrically connected to the charging control port of the second control unit 21 (reference Figure 2 The CO pin of U2 in the middle) and the controlled end of the second charging switch 600 (reference Figure 2 The output terminal of the second discharge switch 500 and the output terminal of the second charge switch 600 (reference Figure 2 The overcharge detection port (reference Figure 2 The CS pin of U2 in the middle) is also connected in series with the input end (reference Figure 2 The S terminal of Q4 is electrically connected, wherein,

[0049] The second control unit 21 is used to detect the voltage of the first battery cell 001 and the second battery cell 002, and detect the negative power input port 203 and the overcharge detection port (reference Figure 2 The voltage between the positive power input port 201, the secondary input port 202 and the negative power input port 203 of the second control unit 21 is determined by detecting the voltage between the positive power input port 201, the secondary input port 202 and the negative power input port 203 of the second control unit 21;

[0050] The second control unit 21 is further used to control the second discharge switch 500 to be disconnected when it is determined that the battery pack is over-discharged. The second control unit 21 is further used to control the second charge switch 600 to be disconnected when it is determined that the battery pack is over-charged.

[0051] It can be understood that in the present embodiment, overcharging includes an overcharging state and a charging overcurrent state, and overdischarging includes an overdischarging state and a discharging overcurrent state. The overcharging state is determined by detecting the voltage of the first battery cell 001 and the second battery cell 002 and the magnitude of the overcharging detection voltage. The overdischarging state is determined by detecting the voltage of the first battery cell 001 and the second battery cell 002 and the magnitude of the overdischarging detection voltage. The charging overcurrent state is determined by detecting the voltage between the negative power input port 203 and the overcharge and discharge detection port and the magnitude of the charging overcurrent detection voltage. The discharging overcurrent state is determined by detecting the voltage between the negative power input port 203 and the overcharge and discharge detection port and the magnitude of the discharging overcurrent detection voltage.

[0052] In some optional embodiments, the second control unit 21 includes but is not limited to a battery protection chip of type SIT8252C, and the second RC filter circuit 22 includes a second resistor (reference Figure 2 R7 and R8 in the second capacitor (reference Figure 2 The L-type RC filter circuit is composed of C3 and C4 in the figure.

[0053] In this embodiment, the second control unit 21 cooperates with the corresponding second RC filter circuit 33 to continuously perform voltage detection on the first battery cell 001 and the second battery cell 002. Figure 3 The battery protection chip U2 corresponding to the second control unit 21 performs voltage detection on the first battery cell 001 through pins VDD and BI, performs voltage detection on the second battery cell 002 through pins BI and B-, and detects the voltage between the negative power input port 203 and the overcharge detection port through pins CS and B-.

[0054] In order to achieve temperature protection for the battery pack, in some embodiments, reference is made to Figure 2 , the input terminal of the second charging switch 600 (reference Figure 2 The electrical connection point between the S terminal of Q4 in the middle) and the negative port P- is also electrically connected to the second temperature sensor RT, and the other end of the second temperature sensor RT is electrically connected to the external device power terminal (reference Figure 2 The network label T in the figure), wherein the second temperature sensor RT is used to detect the temperature of the battery pack during charging and discharging, and transmit the detected temperature signal to the external power-consuming end, so that the external power-consuming end controls the second control unit 21 to perform charging and discharging control according to the received temperature signal.

[0055] To protect the battery pack from abnormal output, refer to Figure 2 In some embodiments, the output protection circuit 700 includes a fuse F1, a third capacitor C5 and a fourth capacitor C6, the fuse F1 is connected in series between the positive electrode of the first battery cell unit 001 and the positive port P+, one end of the third capacitor C5 is electrically connected to the fuse F1 and the positive port P+, and the other end is electrically connected to the fourth capacitor C6, and the end of the fourth capacitor C6 away from the end electrically connected to the third capacitor C5 is electrically connected to the negative port P-.

[0056] It can be understood that an output protection circuit is set between the positive port P+ and the negative port P- of the battery pack. When the output of the battery pack is abnormal (for example, overcurrent caused by short circuit, overvoltage charging and discharging of the battery pack) and charging is impossible or discharging is not stopped under control, the fuse F1 is blown, thereby disconnecting the positive electrode of the battery pack (corresponding to the positive electrode of the first battery cell unit 001) from the positive port P+, thereby stopping the battery pack from charging or discharging, and further protecting the battery pack.

[0057] In order to enable the first charging switch 300, the first discharging switch 400, the second charging switch 600 and the second discharging switch 500, refer to Figure 2 In some embodiments, the first charging switch 300, the first discharging switch 400, the second charging switch 600 and the second discharging switch 500 all include a switch tube (refer to Figure 2The switch tube includes a control terminal (G terminal), an input terminal (S terminal) and an output terminal (D). The control terminal (G terminal of Q1) corresponding to the first discharge switch 300 is connected to the controlled terminal of the first discharge switch 300, the input terminal (S terminal of Q1) corresponding to the first discharge switch 300 is connected to the input terminal of the first discharge switch 300, and the output terminal (D terminal of Q1) corresponding to the first discharge switch 300 is connected to the output terminal of the first discharge switch 300. The control terminal (G terminal of Q2) corresponding to the first charging switch 400 is connected to the controlled terminal of the first charging switch 400, the input terminal (S terminal of Q2) corresponding to the first charging switch 400 is connected to the input terminal of the first charging switch 400, and the output terminal (Q2 terminal of Q1) corresponding to the first charging switch 400 is connected to the output terminal of the first charging switch 400. The D end of Q3 is connected to the output end of the first charging switch 400, the control end (G end of Q3) corresponding to the second discharge switch 500 is connected to the controlled end of the second discharge switch 500, the input end (S end of Q3) corresponding to the second discharge switch 500 is connected to the input end of the second discharge switch 500, the output end (D end of Q3) corresponding to the second discharge switch 500 is connected to the output end of the second discharge switch 500, the control end (G end of Q4) corresponding to the second charging switch 600 is connected to the controlled end of the second charging switch 600, the input end (S end of Q4) corresponding to the second charging switch 600 is connected to the input end of the second charging switch 600, and the output end (D end of Q4) corresponding to the second charging switch 600 is connected to the output end of the second charging switch 600, wherein,

[0058] Switching tube (reference Figure 2 Q1, Q2, Q3, Q4 in the control circuit are used to control the on and off of the input and output terminals according to the enable signal received by the control terminal.

[0059] When the input and output ends of the switch tube Q1 corresponding to the first discharge switch 400 are disconnected, the first discharge switch 400 is disconnected; when the input and output ends of the switch tube Q2 corresponding to the first charging switch 300 are disconnected, the first charging switch 300 is disconnected; when the input and output ends of the switch tube Q3 corresponding to the second discharge switch 500 are disconnected, the second discharge switch 500 is disconnected; when the input and output ends of the switch tube Q4 corresponding to the second charging switch 600 are disconnected, the second charging switch 600 is disconnected.

[0060] It should be noted that the switch tubes in the embodiments of the present application include but are not limited to triodes, MOS tubes, and field effect transistors. Moreover, according to the contents disclosed in the present application, it is easy for a person skilled in the art to modify the switch tube disclosed in the present application into a first charging switch 300, a first discharging switch 400, a second charging switch 600, and a second discharging switch 500 adapted to the selection of the switch tube according to the specific selection of the switch tube. Therefore, whether the switch tube is an NPN-type or PNP-type triode, an N-channel or P-channel switch MOS tube, or an N-type or P-type field effect transistor, the present application can be implemented, and it is not limited in the embodiments of the present application; in some optional implementations, the switch tube is preferably a PAN2060P-type MOS tube.

[0061] Figure 4 This is a structural block diagram of a lithium battery control circuit in another preferred embodiment of the present application. Figure 5 This is a topological structure diagram of the lithium battery control circuit of the preferred embodiment of the present application. In order to isolate one of the first protection unit 100 and the second protection unit 200 from the battery pack, refer to Figure 4 and Figure 5 In some embodiments, a first disconnect switch K1 is provided between the negative power input port 103 of the first protection unit 100 and the second discharge switch 500, and a second disconnect switch K2 is provided between the negative power input port 203 and the negative port P- of the second protection unit 200, wherein,

[0062] When the first circuit breaker K1 is closed, the first protection unit 100 is disconnected from the battery pack;

[0063] When the second circuit breaker K2 is closed, the second protection unit 200 is disconnected from the battery pack;

[0064] When one of the first protection unit 100 and the second protection unit 200 is disconnected from the battery pack, the other one of the first protection unit 100 and the second protection unit 200 continues to protect the battery pack.

[0065] Figure 6 This is a three-dimensional structural diagram of the camera battery compartment of the embodiment of the present application. Figure 7 for Figure 6 A decomposition diagram of Figure 6 and Figure 7 The embodiment of the present application also provides a camera battery compartment, including a compartment box 01, a control board 02 disposed in the compartment box 01, a battery pack 03 disposed in the compartment box 01, and a cover plate 04 covering the compartment box 01, the battery pack 03 is also electrically connected to the control board 02, and the control board 02 is provided with a control circuit for controlling the charging and discharging of the battery pack, wherein the control circuit includes the lithium battery control circuit of any one of the above embodiments.

[0066] It should be noted that, in this article, relational terms such as "first" and "second" 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 "include", "comprise" or any other variants thereof are intended to cover non-exclusive and also include other elements that are not explicitly listed, or also include elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including a..." do not exclude the existence of other identical elements in the process, method, article or device that includes the elements.

[0067] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A lithium battery control circuit, characterized in that: It includes a first protection unit and a second protection unit, wherein the positive power input port of the first protection unit is electrically connected to the positive port, the positive power input port of the second protection unit and the positive electrode of the first battery cell unit respectively, the secondary input port of the first protection unit is electrically connected to the secondary input port of the second protection unit and the electrical connection point between the first battery cell unit and the second battery cell unit respectively, the negative power input port of the first protection unit is electrically connected to the negative electrode of the second battery cell unit, the first protection unit controls the first charging switch and the first discharging switch electrically connected in series, the negative electrode of the second battery cell unit is also electrically connected to the second discharging switch through the first charging switch and the first discharging switch, the second protection unit controls the second charging switch and the second discharging switch electrically connected in series, the end of the second charging switch away from the electrical connection with the second discharging switch is electrically connected to the negative port, and the positive port and the negative port are also coupled to an output protection circuit electrically connected, wherein, The first protection unit is used to control the on and off of the first charging switch and / or the first discharging switch to protect the charging and discharging of the battery pack, wherein the battery pack is composed of the first battery cell unit and the second battery cell unit connected in series; The second protection unit is used to control the on and off of the second charging switch and / or the second discharging switch to protect the charging and discharging of the battery pack; The first protection unit and the second protection unit are further configured such that at least one of them maintains protection for the battery pack; The output protection circuit is used to control the positive electrode of the first battery cell unit to be disconnected from the positive port when the output of the battery pack is abnormal, wherein the first protection unit includes a first control unit and a first RC filter circuit, the first port of the first control unit is electrically connected to the positive power input port of the first protection unit through the first RC filter circuit, the second port of the first control unit is electrically connected to the secondary input port of the first protection unit through the first RC filter circuit, the third port of the first control unit is connected to the negative power input port of the first protection unit, the charge and discharge detection port of the first control unit is electrically connected to the input end of the first discharge switch through a first coupling resistor in series, the discharge control port of the first control unit is electrically connected to the controlled end of the first discharge switch through a second coupling resistor in series, the charge control port of the first control unit is electrically connected to the controlled end of the first charge switch, the first discharge switch is electrically connected to the output end of the first charge switch, and is electrically connected to the negative power input port of the first protection unit through a third coupling resistor, and the load detection port of the first control unit is also electrically connected to the electrical connection point of the first charge switch and the second discharge switch through a fourth coupling resistor in series, wherein, The first control unit is used to determine whether the battery pack is charged and discharged normally by detecting the voltage of the first battery cell unit and the second battery cell unit, and detecting the voltage between the negative power input port and the load detection port thereof, wherein the voltage of the first battery cell unit and the second battery cell unit is determined by detecting the voltage of the positive power input port, the secondary input port and the negative power input port of the first control unit; The first control unit is further used to control the first discharge switch to be disconnected when it is determined that the battery pack is over-discharged, the first control unit is further used to control the first charge switch to be disconnected when it is determined that the battery pack is over-charged, and the first control unit controls the first discharge switch and the first charge switch to be disconnected when it is detected that at least one of the first battery cell unit and the first battery cell unit is disconnected.

2. The lithium battery control circuit according to claim 1, characterized in that: The first control unit includes a battery protection chip of model CM1022-CA, and / or the first RC filter circuit includes an L-type RC filter circuit composed of a first resistor and a first capacitor.

3. The lithium battery control circuit according to claim 2, characterized in that: The first protection unit further includes a temperature protection circuit, which includes a second resistor and a first temperature sensor connected in series, the electrical connection point between the second resistor and the first temperature sensor is electrically connected to the temperature protection detection port of the first control unit, the end of the second resistor away from the electrical connection with the first temperature sensor is electrically connected to the temperature protection reference port of the first control unit, and the end of the first temperature sensor away from the electrical connection with the second resistor is electrically connected to the negative power input port of the first control unit, wherein, The first temperature sensor is used to detect the temperature of the battery pack during charging and discharging, and generate a corresponding first voltage signal; The first control unit is used to control the first charging switch and the first discharging switch to be disconnected when the first voltage signal received by the temperature protection reference port thereof is greater than a preset temperature protection reference voltage.

4. The lithium battery control circuit according to claim 1, characterized in that: The second protection unit includes a second control unit and a second RC filter circuit, wherein the first port of the second control unit is electrically connected to the positive power input port of the second protection unit through the second RC filter circuit, the second port of the second control unit is electrically connected to the secondary input port of the second protection unit through the second RC filter circuit, the third port of the second control unit is connected to the negative power input port of the second protection unit, the discharge control port of the second control unit is electrically connected to the controlled end of the second discharge switch, the charge control port of the second control unit is electrically connected to the controlled end of the second charge switch, the output end of the second discharge switch and the second charge switch are electrically connected, and the overcharge and overdischarge detection port of the second control unit is also electrically connected to the input end of the second charge switch through a fifth coupling resistor in series, wherein, The second control unit is used to determine whether the battery pack is charged and discharged normally by detecting the voltage of the first battery cell unit and the second battery cell unit, and detecting the voltage between the negative power input port and the overcharge and discharge detection port thereof, wherein the voltage of the first battery cell unit and the second battery cell unit is determined by detecting the voltage of the positive power input port, the secondary input port and the negative power input port of the second control unit; The second control unit is further used to control the second discharge switch to be disconnected when it is determined that the battery pack is over-discharged, and the second control unit is further used to control the second charge switch to be disconnected when it is determined that the battery pack is over-charged.

5. The lithium battery control circuit according to claim 4, characterized in that: The second control unit includes a battery protection chip of the SIT8252C model, and / or the second RC filter circuit includes an L-type RC filter circuit composed of a second resistor and a second capacitor.

6. The lithium battery control circuit according to claim 4, characterized in that: The input end of the second charging switch and the electrical connection point of the negative port are also electrically connected to a second temperature sensor, and the other end of the second temperature sensor is electrically connected to the external power terminal, wherein the second temperature sensor is used to detect the temperature of the battery pack during charging and discharging, and transmit the detected temperature signal to the external power terminal, so that the external power terminal controls the second control unit to perform charging and discharging control according to the received temperature signal; The output protection circuit includes a fuse, a third capacitor and a fourth capacitor. The fuse is connected in series between the positive electrode of the first battery cell unit and the positive port. One end of the third capacitor is electrically connected to the fuse and the positive port, and the other end is electrically connected to the fourth capacitor. The end of the fourth capacitor away from the end electrically connected to the third capacitor is electrically connected to the negative port.

7. The lithium battery control circuit according to any one of claims 1 to 6, characterized in that: The first charging switch, the first discharging switch, the second charging switch and the second discharging switch all include a switch tube, and the switch tube includes a control end, an input end and an output end. The control end corresponding to the first discharging switch is connected to the controlled end of the first discharging switch, the input end corresponding to the first discharging switch is connected to the input end of the first discharging switch, the output end corresponding to the first discharging switch is connected to the output end of the first discharging switch, the control end corresponding to the first charging switch is connected to the controlled end of the first charging switch, the input end corresponding to the first charging switch is connected to the input end of the first charging switch, the output end corresponding to the first charging switch is connected to the output end of the first charging switch, the control end corresponding to the second discharging switch is connected to the controlled end of the second discharging switch, the input end corresponding to the second discharging switch is connected to the input end of the second discharging switch, the output end corresponding to the second discharging switch is connected to the output end of the second discharging switch, the control end corresponding to the second charging switch is connected to the controlled end of the second charging switch, the input end corresponding to the second charging switch is connected to the input end of the second charging switch, and the output end corresponding to the second charging switch is connected to the output end of the second charging switch, wherein: The switch tube is used to control the on / off of the input end and the output end according to the enable signal received by the control end; When the input end and the output end of the switch tube corresponding to the first discharge switch are disconnected, the first discharge switch is disconnected; when the input end and the output end of the switch tube corresponding to the first charging switch are disconnected, the first charging switch is disconnected; when the input end and the output end of the switch tube corresponding to the second discharge switch are disconnected, the second discharge switch is disconnected; when the input end and the output end of the switch tube corresponding to the second charging switch are disconnected, the second charging switch is disconnected.

8. The lithium battery control circuit according to claim 7, characterized in that: A first disconnect switch is provided between the negative power input port of the first protection unit and the second discharge switch, and a second disconnect switch is provided between the negative power input port of the second protection unit and the negative port, wherein: When the first circuit breaker is closed, the first protection unit is disconnected from the battery pack; When the second circuit breaker is closed, the second protection unit is disconnected from the battery pack; When one of the first protection unit and the second protection unit is disconnected from the battery pack, the other one of the first protection unit and the second protection unit continues to protect the battery pack.

9. A camera battery compartment, characterized in that: It includes a storage box, a control board arranged in the storage box, a battery pack arranged in the storage box and a cover plate covering the storage box, the battery pack is also electrically connected to the control board, and the control board is provided with a control circuit for controlling the charging and discharging of the battery pack, wherein the control circuit includes the lithium battery control circuit as described in any one of claims 1 to 8.

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