Battery heating circuit and device

Abstract

The utility model relates to the technical field of battery heating, in particular to a battery heating circuit and device. The circuit comprises a coil, a conversion control module, a charging and discharging control module, a conversion module and a heating control module. One end of the coil is connected with the positive electrode of the battery core, and the other end is connected with the conversion control module which is also connected with the negative electrode of the battery core for controlling coil current; the charge-discharge control module is connected with the joint of the cathode of the battery cell and the conversion control module, is also connected with the cathode of the protection plate, and is used for controlling the on-off of the charge-discharge control module; the first end of the conversion module is connected with the charge-discharge control module, and the second end is connected with the charge-discharge control module; the third end of the conversion module is connected with the heating control module, the heating control module is further connected with the connection position of the coil and the positive electrode of the battery cell and used for controlling on-off of the heating control module, and if the heating control module is connected, the heating device heats the battery. The battery heating device can achieve the beneficial effect of heating the battery.

Description

Technical Field

[0001] This application relates to the technical field of battery heating, and particularly to a battery heating circuit and device. Background Art

[0002] The charging and discharging of a battery are affected by the battery temperature. Temperature changes will significantly affect the speed of the internal chemical reaction of the battery and the battery internal resistance, thereby affecting the charging and discharging effect of the battery. Even when the battery temperature is lower than a certain temperature value, the battery may not be able to charge or discharge. In addition, too low battery temperature will also cause attenuation of the battery capacity. Based on this, it can be seen that a battery heating solution needs to be designed to avoid the situation where the charging and discharging of the battery are affected due to too low battery temperature. Utility Model Content

[0003] The purpose of this application is to provide a battery heating circuit and device, which can achieve the beneficial effect of heating the battery.

[0004] The first aspect of this application provides a battery heating circuit: including a coil, a conversion control module, a charge and discharge control module, a conversion module, and a heating control module;

[0005] One end of the coil is connected to the positive electrode of the battery cell, and the other end is connected to one end of the conversion control module. The other end of the conversion control module is connected to the negative electrode of the battery cell, and is used to control the coil current of the coil according to the first control signal received by the conversion control module from an external controller;

[0006] One end of the charge and discharge control module is connected to the connection point between the negative electrode of the battery cell and the conversion control module, and the other end of the charge and discharge control module is connected to the negative electrode of the battery protection board, and is used to control the on / off of the charge and discharge control module according to the temperature control signal sent by the controller, so as to control the start or stop of charging and discharging the battery;

[0007] The first end of the conversion module is connected to one end of the charge and discharge control module, and the second end of the conversion module is connected to the other end of the charge and discharge control module, and is used to bypass the charge and discharge control module to open the power supply circuit for the heating control module if the battery needs to be heated;

[0008] The third end of the conversion module is connected to one end of the heating control module, and the other end of the heating control module is connected to the connection point between the coil and the positive electrode of the battery cell, and is used to control the on / off of the heating control module according to the second control signal received by the heating control module from an external charger. If the heating control module is turned on, the heating device in the heating control module generates heat to heat the battery.

[0009] By adopting the above technical solution, when the external charge and discharge circuit is turned on (i.e., before the access port is ready to start charge and discharge), the external controller receives the judgment signal to determine whether the current battery temperature exceeds the preset temperature, and correspondingly sends a temperature control signal. Here, taking the case where the battery temperature is too low during charging as an example, on the one hand, the temperature control signal will cause the charge and discharge control module to disconnect to suspend the battery charge and discharge; on the other hand, the first control signal sent by the controller will cause the conversion control module to disconnect, so that the coil cannot be powered, and thus the conversion module is adjusted to enter the charging state heating mode; on the third hand, the temperature control signal will control the heating control module to conduct, so that the direction of the current signal is from the positive pole of the battery protection board, through the heating control module, the conversion module to the negative pole of the battery protection board, thereby powering the heating control module to heat the battery.

[0010] Similarly, when discharging, if the battery temperature is too low, on the one hand, the temperature control signal will cause the charge and discharge control module to disconnect to suspend the battery charge and discharge; on the other hand, the first control signal sent by the controller will cause the conversion control module to conduct, so that the coil is powered, and after the coil is powered, the conversion module enters the discharging state heating mode; on the third hand, the temperature control signal controls the heating control module to conduct, so that the direction of the current signal is from the positive pole of the battery cell, through the heating control module, the conversion module to the negative pole of the battery cell, thereby heating the battery under the discharging condition.

[0011] Optionally, the heating control module includes a heating film, one end of the heating film is connected to the connection point of the positive pole of the battery cell and the positive pole of the battery protection board, and the other end is connected to the third end of the conversion module.

[0012] By adopting the above technical solution, when the heating control module conducts, the energized heating film can heat the battery until the battery temperature is higher than the preset temperature value.

[0013] Optionally, the heating control module further includes a first MOS transistor;

[0014] The source electrode of the first MOS transistor is connected to the other end of the heating film, and the drain electrode of the first MOS transistor is connected to the third end of the conversion module;

[0015] The gate electrode of the first MOS transistor is connected to the controller, and is used to control the on-off of the first MOS transistor according to the temperature control signal.

[0016] By adopting the above technical solution, the first MOS transistor is controlled by the temperature control signal, and the temperature control signal is correspondingly sent by the controller according to the temperature sensor signal it receives. When the temperature is too low, the corresponding temperature control signal will turn on the first MOS transistor, so that the heating film is energized to heat the battery.

[0017] Optionally, the heating control module further includes a fuse, one end of the fuse is connected to the connection between the positive electrode of the battery cell and the positive electrode of the battery protection board, and the other end is connected to one end of the heating film.

[0018] By adopting the above technical solution, a fuse is provided in the heating control module, so as to avoid damage to the battery caused by too high heating temperature due to overvoltage, and the fuse will melt during overvoltage to protect the circuit and the battery.

[0019] Optionally, the conversion module includes a conversion switch;

[0020] The first end of the conversion switch is connected to the drain of the first MOS transistor;

[0021] The second end of the conversion switch is connected to the connection between one end of the charge and discharge control module and the negative electrode of the battery protection board;

[0022] The third end of the conversion switch is connected to the connection between the other end of the charge and discharge control module and the negative electrode of the battery cell.

[0023] By adopting the above technical solution, the conversion switch is controlled by the coil. According to the current charging or discharging situation of the battery, there are two situations of current and no current in the coil, so as to switch the current flow direction to the negative electrode of the battery cell or the negative electrode of the battery protection board, thus meeting the battery heating requirements under the battery charge and discharge conditions.

[0024] Optionally, the conversion control module includes a second MOS transistor;

[0025] The source of the second MOS transistor is connected to the other end of the coil, and the drain of the second MOS transistor is connected to the connection between the conversion switch and the negative electrode of the battery cell;

[0026] The gate of the second MOS transistor is connected to the controller, and is used to control the on-off of the second MOS transistor according to the first control signal.

[0027] By adopting the above technical solution, the second MOS transistor will receive the first control signal of the controller. In the case of starting charging, the first control signal will turn off the second MOS transistor, so that the coil cannot be powered on, thereby adjusting the signal flow direction of the conversion switch; similarly, in the case of starting discharging, the first control signal will turn on the second MOS transistor, so that the coil is powered on, thereby adjusting the signal flow direction of the conversion switch to correspond to the starting discharging situation.

[0028] Optionally, the charge and discharge control module includes a third MOS transistor;

[0029] The source electrode of the third MOS transistor is connected to the connection point between the conversion switch and the negative electrode of the battery cell, and the drain electrode of the third MOS transistor is connected to the connection point between the conversion switch and the negative electrode of the battery protection board;

[0030] The gate electrode of the third MOS transistor is connected to the controller, and is used to control the on-off of the third MOS transistor according to the temperature control signal.

[0031] By adopting the above technical solution, the third MOS transistor controls the on-off according to the temperature control signal. In this application, if the temperature value corresponding to the temperature control signal is a signal lower than the preset temperature value, the third MOS transistor is turned off to stop charging and discharging until the temperature reaches above the preset temperature value, thereby avoiding damage to the battery caused by charging and discharging when the battery temperature is too low, and thus improving the battery life.

[0032] The second aspect of this application provides a battery heating device loaded with the above battery heating circuit.

[0033] In summary, this application includes at least one of the following beneficial effects:

[0034] 1. When the external charge and discharge circuit is turned on (that is, before the access port is ready to start charging and discharging), the external controller receives the judgment signal to determine whether the current battery temperature exceeds the preset temperature, and correspondingly sends the temperature control signal. Here, taking the case where the battery temperature is too low during charging as an example, on the one hand, the temperature control signal will cause the charge and discharge control module to turn off to suspend the battery charge and discharge; on the other hand, the first control signal sent by the controller will cause the conversion control module to turn off, so that the coil cannot be powered on, so the conversion module is adjusted to enter the charging state heating mode; on the third hand, the temperature control signal will control the heating control module to turn on, so that the direction of the current signal is from the positive electrode of the battery protection board, through the heating control module, the conversion module to the negative electrode of the battery protection board, so as to supply power to the heating control module to heat the battery;

[0035] Similarly, when discharging, if the battery temperature is too low, on the one hand, the temperature control signal will cause the charge and discharge control module to turn off to suspend the battery charge and discharge; on the other hand, the first control signal sent by the controller will cause the conversion control module to turn on, so that the coil is powered on, and after the coil is powered on, the conversion module enters the discharge state heating mode; on the third hand, the temperature control signal controls the heating control module to turn on, so that the direction of the current signal is from the positive electrode of the battery cell, through the heating control module, the conversion module to the negative electrode of the battery cell, so as to heat the battery during discharge.

[0036] 2. Using coil control to switch between the negative electrode of the battery cell and the negative electrode of the battery protection board, not using MOS control can avoid the problem of no drive when the BMS is not working. No drive is required, and the coil is powered on to work. Description of the Drawings

[0037] Figure 1 is the module connection diagram of the battery heating circuit provided by the embodiments of the present application;

[0038] Figure 2 is the circuit schematic diagram of the battery heating circuit provided by the embodiments of the present application. Detailed implementation manners

[0039] The following embodiments will help those skilled in the art to further understand the function of the present application, but do not limit the present application in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can be made. These all belong to the protection scope of the present application.

[0040] In the following description, specific details such as specific system structures and technologies are proposed for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0041] It should be understood that when used in the description of the present application specification and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0042] It should also be understood that the term "and / or" used in the description of the present application specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0043] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0044] References to "one embodiment" or "some embodiments" or the like described in the specification of the present application mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in one or more embodiments of the present application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized. The terms "comprising", "including", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized.

[0045] The present application will be further described in detail below with reference to the accompanying drawings.

[0046] Referring to Figure 1 , Figure 1 is a module connection diagram of a battery heating circuit provided by an embodiment of the present application, including a coil Relay, a conversion control module, a charge and discharge control module, a conversion module, and a heating control module. Each module will be specifically described below:

[0047] Regarding the conversion control module: The conversion control module includes a conversion switch S1, which is used to adjust the conduction direction of the conversion switch S1 according to whether the coil Relay is powered on, so as to adapt to the usage requirements of both charging start and discharging start situations.

[0048] Regarding the charge and discharge control module: The charge and discharge control module includes a switching device (such as a MOS transistor). The switching device is controlled to turn on and off by a temperature control signal, where the temperature control signal is generated after the controller (such as a single-chip microcomputer) receives the signal from the temperature sensor and processes it. When the battery temperature value is obtained to be lower than the preset temperature value, a corresponding high-level or low-level signal (the specific signal type needs to be adjusted according to PMOS or NMOS) can be sent, so as to turn off the switching device in the charge and discharge control module, thereby ensuring that no charge and discharge operations are performed before the battery temperature rises.

[0049] Regarding the coil Relay and the conversion module: The conversion module is controlled by the coil Relay. In this embodiment, when there is current passing through the coil Relay, the conversion switch S1 in the conversion module is connected to the first contact; when there is no current passing through the coil Relay, the conversion switch S1 is connected to the second contact (normally closed contact).

[0050] Regarding the heating control module: The heating control module includes a heating device (such as the heating film provided in this embodiment), and a switching device (such as a MOS transistor, a triode, etc.). Among them, the switching device in the heating control module is powered and driven by an externally connected charger.

[0051] The following will further specifically describe each module in combination with specific connection relationships:

[0052] One end of the coil Relay is connected to the positive electrode B+ of the battery cell, and the other end is connected to one end of the conversion control module. The other end of the conversion control module is connected to the negative electrode B- of the battery cell, and is used to control the coil Relay current of the coil Relay according to the first control signal received by the conversion control module from an external controller.

[0053] One end of the charge and discharge control module is connected to the connection point between the negative electrode B- of the battery cell and the conversion control module, and the other end of the charge and discharge control module is connected to the negative electrode P- of the battery protection board, and is used to control the on / off of the charge and discharge control module according to the temperature control signal sent by the controller, so as to control the start or stop of battery charging and discharging.

[0054] The first end of the conversion module is connected to one end of the charge and discharge control module, and the second end of the conversion module is connected to the other end of the charge and discharge control module, and is used to bypass the charge and discharge control module to open the power supply circuit for the heating control module if the battery needs to be heated.

[0055] The third end of the conversion module is connected to one end of the heating control module, and the other end of the heating control module is connected to the connection point between the coil Relay and the positive electrode B+ of the battery cell, and is used to control the on / off of the heating control module according to the second control signal received by the heating control module from an external charger. If the heating control module is turned on, the heating device in the heating control module generates heat to heat the battery.

[0056] Specifically, when the external charge and discharge circuit is turned on (that is, before the access port is ready to start charging and discharging), the external controller receives a judgment signal to determine whether the current battery temperature exceeds a preset temperature, and correspondingly sends a temperature control signal. Here, taking the example that the battery temperature is too low during charging, on the one hand, the temperature control signal will cause the charge and discharge control module to disconnect to suspend battery charging and discharging; on the other hand, the first control signal sent by the controller will cause the conversion control module to disconnect, so that the coil Relay cannot be powered on, so the conversion module is adjusted to enter the charging state heating mode; on the third hand, the temperature control signal will control the heating control module to conduct, so that the current signal direction is from the positive electrode P+ of the battery protection board, through the heating control module, the conversion module to the negative electrode P- of the battery protection board, so as to supply power to the heating control module to heat the battery.

[0057] Similarly, when discharging, if the battery temperature is too low, on the one hand, the temperature control signal will cause the charge and discharge control module to disconnect to suspend the battery charge and discharge; on the other hand, the first control signal sent by the controller will cause the conversion control module to conduct, enabling the coil Relay to be powered on. After the coil Relay is powered on, the conversion module enters the discharge state heating mode; on the third hand, the temperature control signal controls the heating control module to conduct, making the current signal direction from the positive electrode B+ of the battery cell, through the heating control module, the conversion module to the negative electrode B- of the battery cell, thereby heating the battery during discharge.

[0058] Please refer to the following Figure 2 , Figure 2 which is the circuit schematic diagram of the battery heating circuit provided by the embodiment of the present application, specifically including:

[0059] Regarding the heating control module: It includes a heating film. One end of the heating film is connected to the connection point between the positive electrode B+ of the battery cell and the positive electrode P+ of the battery protection board, and the other end is connected to the third end of the conversion module.

[0060] Specifically, when the heating control module conducts, the energized heating film can heat the battery until the battery temperature is higher than the preset temperature value.

[0061] The heating control module further includes a first MOS transistor Q1;

[0062] The source electrode of the first MOS transistor Q1 is connected to the other end of the heating film, and the drain electrode of the first MOS transistor Q1 is connected to the third end of the conversion module;

[0063] The gate electrode of the first MOS transistor Q1 is connected to the controller for controlling the on / off of the first MOS transistor Q1 according to the temperature control signal.

[0064] Specifically, the first MOS transistor Q1 is controlled by the temperature control signal. The temperature control signal is sent by the controller according to the temperature sensor signal it receives. When the temperature is too low, the corresponding temperature control signal will turn on the first MOS transistor Q1, so that the heating film is energized to heat the battery.

[0065] Optionally, the heating control module further includes a fuse FUSE. One end of the fuse FUSE is connected to the connection point between the positive electrode B+ of the battery cell and the positive electrode P+ of the battery protection board, and the other end is connected to one end of the heating film.

[0066] Specifically, a fuse FUSE is provided in the heating control module to avoid damage to the battery caused by too high heating temperature due to overvoltage. It will melt during overvoltage to protect the circuit and the battery.

[0067] Regarding the conversion module: It includes a conversion switch S1;

[0068] The first terminal of the conversion switch S1 is connected to the drain of the first MOS transistor Q1;

[0069] The second terminal of the conversion switch S1 is connected to the connection point between one end of the charge and discharge control module and the negative electrode P- of the battery protection board;

[0070] The third terminal of the conversion switch S1 is connected to the connection point between the other end of the charge and discharge control module and the negative electrode B- of the battery cell.

[0071] Specifically, the conversion switch S1 is controlled by the coil Relay. According to the current charging or discharging situation of the battery, there are two situations of current and no current in the coil Relay, so as to switch the current flow direction to the negative electrode B- of the battery cell or the negative electrode P- of the battery protection board, thus meeting the battery heating requirements under the battery charging and discharging conditions.

[0072] Regarding the conversion control module: It includes a second MOS transistor Q2;

[0073] The source of the second MOS transistor Q2 is connected to the other end of the coil Relay, and the drain of the second MOS transistor Q2 is connected to the connection point between the conversion switch S1 and the negative electrode B- of the battery cell;

[0074] The gate of the second MOS transistor Q2 is connected to the controller, and is used to control the on-off of the second MOS transistor Q2 according to the first control signal.

[0075] Specifically, the second MOS transistor Q2 receives the first control signal from the controller. In the case of starting charging, the first control signal will turn off the second MOS transistor Q2, so that the coil Relay cannot be powered on, thus adjusting the signal flow direction of the conversion switch S1; similarly, in the case of starting discharging, the first control signal will turn on the second MOS transistor Q2, so that the coil Relay is powered on, thus adjusting the signal flow direction of the conversion switch S1 to correspond to the starting discharging situation.

[0076] Regarding the charge and discharge control module: It includes a third MOS transistor Q3;

[0077] The source of the third MOS transistor Q3 is connected to the connection point between the conversion switch S1 and the negative electrode B- of the battery cell, and the drain of the third MOS transistor Q3 is connected to the connection point between the conversion switch S1 and the negative electrode P- of the battery protection board;

[0078] The gate of the third MOS transistor Q3 is connected to the controller, and is used to control the on-off of the third MOS transistor Q3 according to the temperature control signal.

[0079] Specifically, the third MOS transistor Q3 controls conduction and cutoff according to the temperature control signal. In this application, if the temperature value corresponding to the temperature control signal is a signal lower than the preset temperature value, the third MOS transistor Q3 is turned off to stop charging and discharging until the temperature reaches above the preset temperature value, thereby avoiding damage to the battery caused by charging and discharging when the battery temperature is too low, and thus improving the battery life.

[0080] The second aspect of this application provides a battery heating device equipped with the above-mentioned battery heating circuit.

[0081] The above embodiments are only used to illustrate the technical solutions of this application, rather than to limit them; although this application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of each embodiment of this application, and should all be included in the protection scope of this application.

Claims

1. A battery heating circuit, characterized in that: It includes a coil, a conversion control module, a charge and discharge control module, a conversion module and a heating control module; One end of the coil is connected to the positive electrode of the battery cell, and the other end is connected to one end of the conversion control module, and the other end of the conversion control module is connected to the negative electrode of the battery cell, and is used to control the coil current of the coil according to the first control signal received by the conversion control module from the external controller; One end of the charge and discharge control module is connected to the connection between the negative electrode of the battery cell and the conversion control module, and the other end of the charge and discharge control module is connected to the negative electrode of the battery protection board, and is used to control the on and off of the charge and discharge control module according to the temperature control signal sent by the controller, thereby controlling the on or off of the battery charge and discharge; The first end of the conversion module is connected to one end of the charge and discharge control module, and the second end of the conversion module is connected to the other end of the charge and discharge control module, so as to bypass the charge and discharge control module and open a power supply circuit for the heating control module if the battery needs to be heated; The third end of the conversion module is connected to one end of the heating control module, and the other end of the heating control module is connected to the connection between the coil and the positive pole of the battery cell, and is used to control the on and off of the heating control module according to a second control signal received by the heating control module from an external charger. If the heating control module is turned on, the heating device in the heating control module generates heat to heat the battery.

2. The battery heating circuit according to claim 1, characterized in that: The heating control module comprises a heating film, one end of which is connected to the connection point between the positive electrode of the battery cell and the positive electrode of the battery protection plate, and the other end of which is connected to the third end of the conversion module.

3. The battery heating circuit according to claim 2, characterized in that: The heating control module also includes a first MOS tube; The source of the first MOS tube is connected to the other end of the heating film, and the drain of the first MOS tube is connected to the third end of the conversion module; The gate of the first MOS tube is connected to the controller, and is used to control the on and off of the first MOS tube according to the temperature control signal.

4. The battery heating circuit according to claim 2, characterized in that: The heating control module also includes a fuse, one end of which is connected to the connection between the positive electrode of the battery cell and the positive electrode of the battery protection plate, and the other end of which is connected to one end of the heating film.

5. The battery heating circuit according to claim 3, characterized in that: The conversion module includes a conversion switch; The first end of the conversion switch is connected to the drain of the first MOS tube; The second end of the conversion switch is connected to the connection between one end of the charge and discharge control module and the negative electrode of the battery protection board; The third end of the conversion switch is connected to the connection point between the other end of the charge and discharge control module and the negative electrode of the battery cell.

6. The battery heating circuit according to claim 5, characterized in that: The conversion control module includes a second MOS tube; The source of the second MOS transistor is connected to the other end of the coil, and the drain of the second MOS transistor is connected to the connection between the conversion switch and the negative electrode of the battery cell; The gate of the second MOS tube is connected to the controller, and is used to control the on and off of the second MOS tube according to the first control signal.

7. The battery heating circuit according to claim 5, characterized in that: The charge and discharge control module includes a third MOS tube; The source of the third MOS tube is connected to the connection between the conversion switch and the negative electrode of the battery cell, and the drain of the third MOS tube is connected to the connection between the conversion switch and the negative electrode of the battery protection board; The gate of the third MOS tube is connected to the controller, and is used to control the on and off of the third MOS tube according to the temperature control signal.

8. A battery heating device, characterized in that: The device is equipped with a battery heating circuit as claimed in any one of claims 1 to 7.

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