WO2023178550A1

WO2023178550A1 - Battery pack, battery heating method, and electronic device

Info

Publication number: WO2023178550A1
Application number: PCT/CN2022/082488
Authority: WO
Inventors: 郭永林; 崔立志
Original assignee: 东莞新能安科技有限公司
Priority date: 2022-03-23
Filing date: 2022-03-23
Publication date: 2023-09-28

Abstract

Provided in the embodiments of the present application are a battery pack, a battery heating method, and an electronic device. The battery pack comprises a battery heating circuit, a cell module, and a heater. The battery heating circuit comprises a controller and a first switch, wherein the first switch can receive a control signal of the controller to switch on or switch off; the first switch is electrically connected to the cell module and the heater to form a first circuit; and the first switch is configured to receive a control signal of the controller to switch on in response to the temperature of the cell module being not lower than a temperature threshold value, so as to turn on the first circuit, such that the temperature of the heater rises to heat the cell module. The cell module comprises at least one cell, and the heater comprises at least one sub-heater, wherein the sub-heater corresponds to the cell on a one-to-one basis; and each sub-heater comprises at least two metal terminals, which are led out from the interior of the cell. The solution can improve the charging and discharging performance of a rechargeable battery in a low-temperature environment.

Description

Battery pack, battery heating method and electronic device

Technical field

Embodiments of the present application relate to the field of electrical engineering technology, and in particular, to a battery pack, a battery heating method and an electronic device.

Background technique

Secondary batteries, such as lithium-ion batteries, sodium-ion batteries, etc., have the advantages of high energy density, long cycle life, high nominal voltage, low self-discharge rate, small size, and light weight. They are widely used in consumer electronics, drones, and electric vehicles. It is widely used in automobiles and other products. When the ambient temperature is low, the chemical reaction rate of the secondary battery is slow, which affects the normal charging and discharging of the secondary battery. Moreover, when the secondary battery is discharged in a low-temperature environment, it is easy to cause irreversible damage to the performance of the secondary battery. Therefore, it is necessary to provide a technical solution to improve the charge and discharge performance of secondary batteries in low temperature environments.

Contents of the invention

In view of this, embodiments of the present application provide a battery pack, a battery heating method and an electronic device to improve the charging and discharging performance of secondary batteries in low-temperature environments.

According to a first aspect of the embodiment of the present application, a battery pack is provided, including: a battery heating circuit, a battery core module and a heater. The battery heating circuit includes a controller and a first switch. The first switch receives The control signal of the controller performs on or off, and the first switch is electrically connected to the battery core module and the heater. The first switch is configured to receive a control signal from the controller to perform conduction in response to the temperature of the battery module being not lower than a temperature threshold, and the battery module, the first switch and the The first circuit where the heater is located is turned on, causing the temperature of the heater to rise to heat the battery core module. The battery core module includes at least one battery core, and the heater includes at least one sub-heater, wherein the sub-heaters correspond to the battery core one-to-one, and each of the sub-heaters includes at least two Metal terminals, the metal terminals are led out from the inside of the battery core.

In some embodiments, the control end of the first switch is electrically connected to the controller for receiving a control signal from the controller. The first end of the first switch is electrically connected to the positive electrode of the battery core module, the second end of the first switch is electrically connected to the first end of the heater, and the second end of the heater is electrically connected to the negative electrode of the battery core module; or, the first end of the heater is electrically connected to the positive electrode of the battery core module, and the second end of the heater is electrically connected to the third terminal of the first switch. The two ends are electrically connected, and the first end of the first switch is electrically connected to the negative electrode of the battery module.

In some embodiments, the battery heating circuit further includes: a second switch and a charging port. The second switch is electrically connected to the heater and the charging port respectively, and receives a control signal from the controller to execute On or off. The second switch is configured to receive a control signal from the controller to perform conduction in response to the temperature of the battery module being lower than the temperature threshold, and the charging port is configured to be electrically connected to a charger, So that the charger, the second switch and the second circuit where the heater is located are turned on.

In some embodiments, the control end of the second switch is electrically connected to the controller for receiving a control signal from the controller, and the charging port includes a first charging port and a second charging port. The first end of the second switch is electrically connected to the first charging port, the second end of the second switch is electrically connected to the first end of the heater, and the second end of the heater is electrically connected to the first charging port. The second charging port is electrically connected; or, the first end of the heater is electrically connected to the first charging port, and the second end of the heater is electrically connected to the second end of the second switch, so The first end of the second switch is electrically connected to the second charging port.

In some embodiments, when the first switch receives a control signal from the controller to turn on, the second switch receives a control signal from the controller to turn off; or, when the second switch receives a control signal from the controller, it turns off. When the control signal of the controller is turned on, the first switch receives the control signal of the controller and is turned off.

In some embodiments, the battery heating circuit further includes: a detector, the detector is electrically connected to the battery core module and the controller respectively, and is used to obtain the temperature information of the battery core module, The temperature information is sent to the controller, and the detector is configured to detect the temperature of the battery core module in response to the controller waking up.

In some embodiments, the controller is configured to wake up in response to a power-on signal entering the working state from the sleep state; or to wake up in response to a charger accessing the charging port and receiving a charging signal.

In some embodiments, the second switch is configured to receive a control signal from the controller to perform shutdown in response to a voltage of the charger being higher than a first voltage threshold.

In some embodiments, the battery heating circuit further includes: a first diode. The anode of the first diode is electrically connected to the anode of the battery module, and the cathode of the first diode is electrically connected to the first switch.

In some embodiments, the battery heating circuit further includes: a second diode. The anode of the second diode is electrically connected to the charging port, and the cathode of the second diode is electrically connected to the second switch.

In some embodiments, the heater includes more than three sub-heaters, and each of the sub-heaters forms any of the following electrical connection forms: (i) The sub-heaters form a series electrical connection. connection; or, (ii) a parallel electrical connection is formed between the sub-heaters; or, (iii) a mixed electrical connection is formed between the sub-heaters.

In some embodiments, the battery heating circuit further includes: a third switch and a fourth switch, the third switch and the fourth switch being connected in series. The third switch and the fourth switch are electrically connected between the positive electrode of the battery core module and the positive output terminal of the battery core module; or, the third switch and the fourth switch are electrically connected Connected between the negative electrode of the battery cell module and the negative electrode output terminal of the battery cell module.

According to a second aspect of the embodiment of the present application, a battery heating method is provided, which is applied to the battery pack in the first aspect. The battery heating method includes: in response to the temperature of the battery module being not lower than the temperature threshold, The controller sends a control signal to the first switch; the first switch performs conduction in response to the received control signal, and the battery module, the first switch and the first circuit where the heater is located are conductive, causing The temperature of the heater rises to heat the battery core module; or, in response to the temperature of the battery core module being lower than the temperature threshold, the controller sends a control signal to the second switch; The second switch is turned on in response to the received control signal, and the charger, the second switch, and the second circuit in which the heater is located are turned on, causing the temperature of the heater to rise to increase the temperature of the heater. The battery module is heated.

According to a third aspect of the embodiments of the present application, an electronic device is provided, including the battery pack of the first aspect.

According to the battery heating solution provided by the embodiment of the present application, when the ambient temperature is low, in response to the temperature of the battery module not being lower than the temperature threshold, the controller can send a control signal to the first switch to turn on the first switch. , after the first switch is turned on, the battery module, the first switch and the first circuit where the heater is located are turned on, and the battery module supplies power to the heater, causing the temperature of the heater to rise to inflate the battery module. Heating is performed so that the battery module can rise to a suitable temperature in a short period of time, thereby improving the charging and discharging performance of the battery module in a low-temperature environment.

Description of the drawings

In order to explain the embodiments of the present application or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some of the embodiments recorded in the embodiments of this application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

Figure 1 is a schematic block diagram of a battery pack according to an embodiment of the present application;

Figure 2 is a schematic diagram of a battery heating circuit according to an embodiment of the present application;

Figure 3 is a schematic diagram of a battery heating circuit according to another embodiment of the present application;

Figure 4 is a schematic diagram of a battery heating circuit according to another embodiment of the present application;

Figure 5 is a schematic block diagram of a battery pack according to another embodiment of the present application;

Figure 6 is a schematic block diagram of a battery pack according to another embodiment of the present application;

Figure 7 is a schematic diagram of a battery core according to an embodiment of the present application;

Figure 8 is a schematic diagram of a heating plate according to an embodiment of the present application;

Figure 9 is a flow chart of a battery heating method according to an embodiment of the present application.

Detailed ways

In order to enable those in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and in detail below in conjunction with the drawings in the embodiments of the present application. Obviously, the description The embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the examples in the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art should fall within the scope of protection of the embodiments of this application.

The specific implementation of the embodiments of the present application will be further described below with reference to the accompanying drawings.

Secondary batteries are rechargeable batteries that rely on metal ions, such as lithium ions and sodium ions, to move between the positive and negative electrodes. They are widely used in consumer electronics, drones, electric vehicles and other products. application. The working principle of the secondary battery is that the internal electrolyte changes through chemical reactions, and a potential difference occurs between the positive and negative electrodes, thereby causing current flow. In a low-temperature environment, the movement speed of the electrolyte slows down, which affects the transfer activity of metal ions between the positive and negative electrodes, resulting in a decrease in battery charge and discharge performance. Moreover, discharge of the secondary battery in a low-temperature environment can easily cause damage to the secondary battery. Therefore, there is an urgent need for a solution to increase the temperature of the secondary battery, to heat the secondary battery in a low-temperature environment, and to improve the charge and discharge performance of the secondary battery in a low-temperature environment.

battery pack

Figure 1 is a schematic block diagram of a battery pack according to an embodiment of the present application. As shown in Figure 1, the battery pack 100 includes a battery heating circuit 10, a battery module 20 and a heater 30. The battery heating circuit 10 includes a controller 11 and a first switch 12. The first switch 12 is a controllable switch that can receive According to the control signal of the controller 11, the circuit is turned on or off. The first switch 12 is electrically connected to the battery module 20 and the heater 30 . In response to the temperature of the battery module 20 not being lower than the temperature threshold, the first switch 12 can receive a control signal from the controller 11 to perform conduction, so that the battery module 20 , the first switch 12 and the first switch 12 where the heater 30 is located. The circuit is turned on, thereby increasing the temperature of the heater 30 to heat the battery module 20 .

In the embodiment of the present application, when the ambient temperature is low, in response to the temperature of the battery module 20 not being lower than the temperature threshold, the controller 11 can send a control signal to the first switch 12 to cause the first switch 12 to turn on. , after the first switch 12 is turned on, the battery module 20, the first switch 12 and the first circuit where the heater 30 is located are turned on, and the battery module 20 supplies power to the heater 30, causing the temperature of the heater 30 to rise. , to heat the battery module 20 so that the battery module 20 can rise to a suitable temperature in a short period of time, thereby improving the charging and discharging performance of the battery module 20 in a low-temperature environment.

It should be understood that the battery pack 100 may include a battery module, a heater and a battery management system (Battery Management System, BMS), and the battery heating circuit 10 may be provided on the BMS. In a specific implementation, the BMS is based on a circuit board. The BMS circuit board can manage the charge and discharge of the battery module.

It should also be understood that the controller 11 can be disposed on the BMS circuit board, and in response to the temperature of the battery module 20 not being lower than the temperature threshold, sending a control signal to the first switch 12 means that the controller can obtain the battery module 20 The temperature information of the battery module 20 or the temperature information of the environment where the battery module 20 is located. When the temperature of the battery module 20 is low enough to affect normal charging and discharging, but the temperature of the battery module 20 is not lower than the temperature threshold, the controller 11 can The first switch 12 sends a control signal to turn on the first switch 12 and the battery module 20 supplies power to the heater 30 so that the heater 30 heats the battery module 20 . In one implementation, after the temperature of the battery module 20 is lower than 0°C, for example, when the temperature of the battery module 20 is -15°C, or the ambient temperature of the battery pack 100 is -15°C, the low temperature will It has a greater impact on the charge and discharge performance of the battery module 20. The temperature threshold is -20°C. When the temperature of the battery module 20 is between -20°C and 0°C, the battery module 20 can move to the first The switch 12 sends a control signal to cause the first switch 12 to perform conduction.

When the temperature of the battery module 20 is relatively high, there is no need to heat the battery module 20 . Therefore, when the temperature of the battery module 20 is so low that it affects the normal charging and discharging of the battery module 20 , the controller 11 can send a signal to the third battery module 20 . A switch 12 sends the control signal. When the temperature of the battery module 20 is lower than the temperature threshold, the BMS circuit board can turn off the discharge of the battery module 20, because if the battery module 20 discharges at a temperature lower than the temperature threshold, it will cause problems for the battery module. The performance of the battery cells included in 20 causes irreversible damage, so after the temperature of the battery module 20 is lower than the temperature threshold (for example -20°C), the controller 11 will not send a control signal to the first switch 12, and the first switch 12 is in the off state, and the battery module 20 no longer supplies power to the heater 30 .

2 to 4 are schematic diagrams of three battery heating circuits provided by embodiments of the present application. As shown in FIGS. 2 to 4 , the control end of the first switch 12 is electrically connected to the controller 11 , and the first switch 12 receives the control signal of the controller 11 through the control end. As shown in FIGS. 2 and 3 , the first end of the first switch 12 is electrically connected to the positive electrode of the battery module 20 , and the second end of the first switch 12 is electrically connected to the first end of the heater 30 . The heater 30 The second end is electrically connected to the negative electrode of the battery module 20 . As shown in FIG. 4 , the first end of the heater 30 is electrically connected to the positive electrode of the battery module 20 , the second end of the heater 30 is electrically connected to the second end of the first switch 12 , and the first end of the first switch 12 is electrically connected. The terminal is electrically connected to the negative electrode of the battery module 20 .

The control end of the first switch 12 is electrically connected to the controller 11. The controller 11 can send a control signal to the control end of the first switch 12 to turn the first switch 12 on or off, thereby causing the battery module 20, The first switch 12 and the first circuit where the heater 30 is located are connected or disconnected to start heating the battery core module 20 or to stop heating the battery core module 20 . As shown in Figures 2 and 3, when the controller 11 controls the positive electrode of the battery module 20, the first switch 12 is electrically connected between the positive electrode of the battery module 20 and the heater 30, as shown in Figure 4. When the controller 11 controls the negative electrode of the battery module 20 , the first switch 12 is electrically connected between the heater 30 and the negative electrode of the battery module 20 .

In one embodiment of the present application, the control end of the first switch 12 is electrically connected to the controller 11, and the first switch 12 can be electrically connected between the positive electrode of the battery core module 20 and the heater 30 to realize control of the battery core module. The positive terminal of group 20 is controlled. In another embodiment of the present application, the first switch 12 can also be electrically connected between the heater 30 and the negative electrode of the battery module 20 to control the negative electrode of the battery module 20 . The controller 11 can control the positive electrode or the negative electrode of the battery module 20, and control the on and off of the first switch 12. It is suitable for the battery management system of positive electrode control and negative electrode control, and improves the battery provided by the embodiment of the present application. Suitability of heating circuit.

In this embodiment of the present application, the first switch 12 may be a controllable switch including a control terminal, an input terminal, and an output terminal. For example, the first switch 12 may be a triode, a PMOS tube, or an NMOS tube. When the first switch 12 is a MOS transistor (PMOS transistor or NMOS transistor), the first switch 12 shown in Figures 2 and 3 is a PMOS transistor, and the first switch 12 shown in Figure 4 is an NMOS transistor. The gate of the MOS tube is the control terminal of the first switch 12 , the source of the MOS tube is the first terminal of the first switch 12 , and the drain of the MOS tube is the second terminal of the first switch 12 .

Figure 5 is a schematic block diagram of a battery heating circuit provided by yet another embodiment of the present application. As shown in FIG. 5 , the battery heating circuit 10 includes, in addition to the controller 11 and the first switch 12 , a second switch 13 and a charging port 14 . Charging port 14 can be electrically connected to charger 40 . The second switch 13 is electrically connected to the heater 30 and the charging port 14 respectively. The second switch 13 is a controllable switch that can receive a control signal from the controller 11 and perform on or off based on the received control signal. In response to the temperature of the battery module 20 being lower than the temperature threshold (for example -20° C.), the second switch 13 receives the control signal from the controller 11 and performs conduction, so that the charger 40 , the second switch 13 and the heater 30 are in the The second circuit is turned on, thereby increasing the temperature of the heater 30 to heat the battery module 20 .

In the embodiment of the present application, when the temperature of the battery module 20 is lower than the temperature threshold, the BMS circuit board can turn off the discharge switch to prevent the battery module 20 from discharging, because the battery module 20 is lower than the temperature threshold. Continuing to discharge in the environment may cause irreversible damage to the performance of the battery module 20. At this time, the battery module 20 no longer supplies power to the heater 30. After the charger 40 is connected to the battery pack through the charging port 14, the controller 11 can respond to the charging handshake signal sent by the charger 40, and can send a control signal to the second switch 13 to turn on the second switch 13. After the switch 13 is turned on, the charger 40, the second switch 13 and the second circuit where the heater 30 is located are turned on, and the charger 40 supplies power to the heater 30, causing the temperature of the heater 30 to rise to inflate the battery module. 20 is heated, thereby allowing the battery module 20 to rise to a suitable temperature in a relatively short period of time, thereby improving the charging and discharging performance of the battery module 20 in a low-temperature environment.

When the temperature of the battery module 20 is lower than the temperature threshold (for example -20°C), the BMS circuit board controls the battery module 20 not to discharge. Therefore, the heater 30 cannot be powered through the battery module 20. At this time, the heater 30 can be powered by The charging port 14 is electrically connected to the charger 40. The controller 11 controls the second switch 13 to be turned on, and the charger 40 supplies power to the heater 30, so that the temperature of the heater 30 increases to heat the battery module 20. After the temperature of the battery module 20 rises to a suitable temperature, the BMS circuit board controls the battery module 20 to perform normal charging and discharging.

In an implementation manner of the present application, as shown in Figure 3, the control end of the second switch 13 is electrically connected to the controller 11, the control end of the second switch 13 can receive the control signal of the controller 11, and the charging port 14 includes a first Charging port C+ and second charging port C-. As shown in Figure 3, the first end of the second switch 13 is electrically connected to the first charging port C+, the second end of the second switch 13 is electrically connected to the first end of the heater 30, and the second end of the heater 30 is electrically connected to Second charging port C - electrical connection. In another implementation of the present application, as shown in FIG. 4 , the first end of the heater 30 is electrically connected to the first charging port C+, and the second end of the heater 30 is electrically connected to the second end of the second switch 13 , the first end of the second switch 13 is electrically connected to the second charging port C-.

The control end of the second switch 13 is electrically connected to the controller 11. The controller 11 can send a control signal to the control end of the second switch 13 to turn the second switch 13 on or off, thereby causing the charger 40 and the second switch 13 to turn on or off. The switch 13 and the second circuit where the heater 30 is located are connected or disconnected, causing the charger 40 to start or stop supplying power to the heater 30, and then start or stop heating the battery module 20. When the controller 11 controls the positive electrode of the battery module 20 , the second switch 13 is electrically connected between the first charging port C+ and the heater 30 . When the controller 11 controls the negative electrode of the battery module 20, the second switch 13 is electrically connected between the heater 30 and the second charging port C-.

In an embodiment of the present application, the control end of the second switch 13 is electrically connected to the controller 11, and the second switch 13 can be electrically connected between the first charging port C+ and the heater 30 to realize the control of the battery module 20. positive pole for control. In another embodiment of the present application, the second switch 13 can be electrically connected between the heater 30 and the second charging port C- to control the negative electrode of the battery module 20 . The controller 11 can control the positive electrode or the negative electrode of the battery module 20, and control the on and off of the second switch 13. It is suitable for battery management systems with positive electrode control and negative electrode control, and improves the performance provided by the embodiments of the present application. Suitability of battery heating circuit.

In this embodiment of the present application, the second switch 13 may be a controllable switch including a control terminal, an input terminal, and an output terminal. For example, the second switch 13 may be a triode, a PMOS tube, or an NMOS tube. When the second switch 13 is a MOS tube (PMOS tube or NMOS tube), the second switch 13 shown in Figure 3 is a PMOS tube, the second switch 13 shown in Figure 4 is an NMOS tube, and the gate of the MOS tube is the second switch 13 The control end of the MOS tube is the source of the second switch 13 and the drain of the MOS tube is the second end of the second switch 13 .

Figure 6 is a schematic block diagram of a battery heating circuit provided by yet another embodiment of the present application. As shown in FIG. 6 , the battery heating circuit 10 also includes a detector 15 . The detector 15 is electrically connected to the battery module 20 and the controller 11 respectively. The detector 15 can obtain the temperature information of the battery module 20 and send the temperature information to the controller 11 . In response to the controller 11 waking up, the detector 15 can detect the temperature of the cell module 20 .

In the embodiment of the present application, after the controller 11 wakes up from the sleep mode and enters the working mode, the controller 11 can send a control signal to the detector 15 so that the detector 15 detects the temperature of the battery module 20 to obtain the information for Temperature information indicating the temperature of the battery module 20 is sent to the controller 11, and the controller 11 can control the on/off of the first switch 12 and/or the second switch 13 according to the temperature information, so as to When the temperature of the battery module 20 is low, the battery module 20 is heated. When the controller 11 is in the sleep mode, the detector 15 does not detect the temperature of the battery module 20 to reduce the power consumption of the battery pack 100 . After the controller 11 is awakened, the battery module 20 starts charging and discharging. The detector 15 detects the temperature of the battery module 20 to heat the battery module 20 in time when the temperature of the battery module 20 is low. , ensuring that the battery module 20 can quickly perform normal charging and discharging.

It should be understood that the wake-up state of the controller 11 can be represented by the BMS circuit board being in a working state, and the non-wake-up state of the controller 11 can be represented by the BMS circuit board being in a low-power consumption state. The non-wake-up state includes but is not limited to the sleep state and the standby state. , shutdown state, etc. Specifically, when the BMS circuit board is in a low power consumption state, some circuits are not used. Accordingly, the controller 11 is in a non-awakened state and disconnects the power supply of some circuits, such as disconnecting the power supply of the detector 15, to achieve The low power consumption of the battery pack 100 is achieved.

In one example, the detector 15 may be a temperature sensor provided on the surface of the battery module 20 , or may be an analog acquisition front end (Analog Front End, AFE) chip provided on the BMS circuit board.

In one implementation, the awakening of the controller 11 includes various forms, such as responding to a start-up signal of an electronic device (such as an electric two-wheeled vehicle, a drone, an electric tool, etc.), the controller 11 enters the working state from the sleep state. , the controller 11 is awakened, or in response to the charger 40 being connected to the charging port 14, the controller 11 receives a charging signal, and the controller 11 is awakened.

The controller 11 receives a power-on signal triggered by the user through a power-on button, etc. The controller 11 is awakened after receiving the power-on signal, and then the controller 11 obtains the temperature information of the detector 15 to detect when the temperature of the battery module 20 is low. When the power supply line of the heater 30 is turned on, the battery core module 20 is heated through the heater 30, so that the battery core module 20 is at a more suitable temperature. After the charger 40 is connected to the charging port 14, the controller 11 can receive the charging handshake signal sent by the charger 40 and be awakened. Then the controller 11 obtains the temperature information of the detector 15 to detect when the temperature of the battery module 20 is low. When the power supply line of the heater 30 is turned on, the battery core module 20 is heated through the heater 30, so that the battery core module 20 is at a more suitable temperature.

In the embodiment of the present application, the controller 11 wakes up after receiving a power-on signal or a charging signal. After waking up, the controller 11 can control the detector 15 to detect the temperature of the battery module 20, and then detect the temperature of the battery module 20. When the temperature is low, the power supply line of the heater 30 is turned on, and the battery module 20 is heated by the heater 30 so that the battery module 20 can be charged or discharged normally, which can ensure that the battery module 20 can operate in a low-temperature environment. Normal charging and discharging can also reduce the power consumption of the battery heating circuit 10 .

In one implementation, in response to the voltage of the charger 40 being higher than the first voltage threshold, the second switch 13 receives the control signal from the controller 11 to perform shutdown.

In the embodiment of the present application, as shown in Figure 3 or Figure 4, after the second switch 13 is turned on, the charger 40 supplies power to the heater 30, and the controller 11 obtains the first charging port C+ and the second charging port C-. This voltage is the output voltage of the charger 40. If the controller 11 determines that the voltage is higher than the first voltage threshold, it sends a control signal to the second switch 13 to turn off the second switch 13 to avoid The heater 30 is burned out, ensuring the safety of heating the battery module 20 . In one specific embodiment, the first voltage threshold may be the rated voltage of the battery module 20 . In another optional embodiment, the first voltage threshold may be greater than the rated voltage of the battery module 20 , for example It can be 5V, 10V or 15V higher than the rated voltage of the battery module 20. The above specific value of the first voltage threshold is only an example and does not constitute a limitation on the first voltage threshold.

In one implementation, as shown in Figures 2 to 4, the battery heating circuit 10 further includes a first diode 16. The anode of the first diode 16 is electrically connected to the anode of the battery module 20. The first The cathode of diode 16 is electrically connected to first switch 12 .

Specifically, in the battery heating circuit 10 shown in FIGS. 2 and 3 , the anode of the first diode 16 is electrically connected to the anode of the battery module 20 , and the cathode of the first diode 16 is electrically connected to the first switch 12 The first end is electrically connected. In the battery heating circuit 10 shown in FIG. 4 , the positive electrode of the battery module 20 is electrically connected to the first end of the heater 30 , and the second end of the heater 30 is electrically connected to the anode of the first diode 16 , that is, The anode of the first diode 16 is indirectly electrically connected to the anode of the battery module 20 through the heater 30 , and the cathode of the first diode 16 is electrically connected to the second terminal of the first switch 12 .

In the embodiment of the present application, the anode of the first diode 16 is electrically connected to the anode of the battery module 20, and the cathode of the first diode 16 is electrically connected to the first switch 12. Based on the one-way conductive performance of the diode, The current in the first circuit can only flow from the battery module 20 to the first switch 12, but not from the first switch 12 to the battery module 20, thus avoiding the occurrence of short circuit and other faults and ensuring that the battery heating circuit 10 and Battery management system safety.

In one implementation, as shown in FIGS. 3 and 4 , the battery heating circuit 10 further includes a second diode 17 , the anode of the second diode 17 is electrically connected to the charging port 14 , and the second diode 17 The cathode is electrically connected to the second switch 13 .

Specifically, in the battery heating circuit 10 shown in FIG. 3 , the anode of the second diode 17 is electrically connected to the first charging port C+, and the cathode of the second diode 17 is electrically connected to the first terminal of the second switch 13 . connect. In the battery heating circuit 10 shown in Figure 4, the first end of the heater 30 is electrically connected to the first charging port C+, the second end of the heater 30 is electrically connected to the anode of the second diode 17, and the second end of the heater 30 is electrically connected to the anode of the second diode 17. The cathode of the pole tube 17 is electrically connected to the second terminal of the second switch 13 .

In the embodiment of the present application, the anode of the second diode 17 is electrically connected to the charging port 14, and the cathode of the second diode 17 is electrically connected to the second switch 13. Based on the unidirectional conduction performance of the diode, the second circuit The current in the battery can only flow from the charger 40 to the second switch 13, but not from the second switch 13 to the charger 40. This avoids short circuit and other faults and ensures the safety of the battery heating circuit 10 and the battery management system.

In one implementation, as shown in FIGS. 2 to 4 , the battery heating circuit 10 further includes a third switch 18 and a fourth switch 19 , and the third switch 18 and the fourth switch 19 are connected in series. As shown in FIGS. 2 and 3 , the third switch 18 and the fourth switch 19 may be electrically connected between the positive electrode of the battery module 20 and the positive output terminal P+ of the battery module 20 . As shown in FIG. 4 , the third switch 18 and the fourth switch 19 can also be electrically connected between the negative electrode of the battery module 20 and the negative output terminal P- of the battery module 20 .

In the embodiment of the present application, the third switch 18 and the fourth switch 19 are controllable switches provided on the BMS circuit board for controlling the charging and discharging of the battery module 20. The control of the third switch 18 and the fourth switch 19 Both terminals are electrically connected to the controller 11. The controller 11 sends control signals to the third switch 18 and the fourth switch 19 to turn the third switch 18 and the fourth switch 19 on or off to control the battery module 20. charge and discharge are controlled. The circuit where the third switch 18 and the fourth switch 19 are located is connected in parallel with the circuit where the first switch 12 and/or the second switch 13 is located, so that when the third switch 18 and the fourth switch 19 are both turned off, the first switch 12 or After the second switch 13 is turned on, the battery module 20 can still be heated, so that the battery module 20 can be preheated before charging or discharging, ensuring that the battery module 20 can Normal charging and discharging in a low temperature environment can also extend the service life of the battery module 20 .

In one implementation, the third switch 18 and the fourth switch 19 may be power tubes. For example, in the battery heating circuit 10 shown in FIGS. 2 to 4 , the third switch 18 and the fourth switch 19 are both NMOS tubes. .

In the embodiment of the present application, the charging port and the discharging port of the battery module 20 are the same port as an example. That is, the first charging switch C+ can be used as the positive output terminal P+ of the battery module 20, and the second charging switch C+ can be used as the positive output terminal P+ of the battery module 20. Port C- can be used as the negative output terminal P- of the battery module 20. When actual business is implemented, the charging port and the discharge port of the battery module 20 can be the same port or different ports. This application implements This example does not limit this.

The working process of the battery heating circuit 10 shown in FIGS. 2 to 4 will be described in detail below.

As shown in FIG. 2 , in response to the temperature of the battery module 20 not being lower than the preset temperature threshold, the controller 11 sends a control signal to the first switch 12 to turn on the first switch 12 . If the charger 40 is not connected to the charging port 14, after the first switch 12 is turned on, the circuit including the battery module 20, the first diode 16, the first switch 12 and the heater 30 is turned on, and the battery module 20 supplies power to the heater 30 to increase the temperature of the heater 30 to heat the battery module 20 . If the charger 40 is connected to the charging port 14 and the first switch 12 is turned on, based on the unidirectional conduction performance of the first diode 16 and the second diode 17, if the output voltage of the battery module 20 is greater than the charger When the output voltage is 40, the circuit including the battery module 20, the first diode 16, the first switch 12 and the heater 30 is turned on, and the battery module 20 supplies power to the heater 30, causing the temperature of the heater 30 to rise. high to heat the battery module 20. If the output voltage of the battery module 20 is less than the output voltage of the charger 40, the charger 40, the second diode 17, the first switch 12 and the heater 30 are located. When the circuit is turned on, the charger 40 supplies power to the heater 30 to increase the temperature of the heater 30 to heat the battery module 20 .

As shown in FIGS. 3 and 4 , in response to the temperature of the battery module 20 not being lower than the preset temperature threshold, the controller 11 sends a control signal to the first switch 12 to turn on the first switch 12 , and the first switch 12 turns on. The second switch 13 remains off. After the first switch 12 is turned on, the circuit including the battery module 20, the first diode 16, the first switch 12 and the heater 30 is turned on, and the battery module 20 becomes a heater. 30 supplies power to raise the temperature of the heater 30 to heat the battery module 20 . In response to when the charger 40 is connected to the charging port 14, the controller 11 obtains the temperature of the battery module 20. If the temperature of the battery module 20 is lower than the preset temperature threshold, the controller 11 sends control to the second switch 13. signal, causing the second switch 13 to turn on, while the first switch 12 remains off. After the second switch 13 turns on, the circuit where the charger 40, the second diode 17, the second switch 13 and the heater 30 are located When the battery is turned on, the charger 40 supplies power to the heater 30 to increase the temperature of the heater 30 to heat the battery module 20 .

As shown in Figures 3 and 4, the first switch 12 is connected in series with the first diode 16, and the second switch 13 is connected in series with the second diode 17. A logic error occurs in the controller 11, for example, the control signal sent by the controller 11 The signal turns on both the first switch 12 and the second switch 13. Based on the unidirectional conduction performance of the first diode 16 and the second diode 17, it can prevent the third switch 18 and the fourth switch 19 from being closed. short circuit occurs to prevent the first switch 12 and the second switch 13 from being burned.

The second diode 17 may be a Schottky diode. Since the Schottky diode has an over-current protection function, when an over-current fault occurs in the charger 40, that is, when the output current of the charger 40 is greater than the set value, the second diode 17 (Schottky diode) fuses and protects the second diode 17. Two switches 13 and heater 30. When the second diode 17 is a Schottky diode, based on the overcurrent protection function of the Schottky diode, the battery heating circuit 10 does not need an additional fuse, ensuring that the battery heating circuit 10 has a lower cost.

In one implementation, as shown in FIGS. 2 to 4 , the battery core module 20 includes at least one battery core 21 , and the heater 30 includes at least one sub-heater 31 . The sub-heaters 31 correspond to the electric core 21 one-to-one. Each sub-heater 31 includes at least two metal terminals, and the metal terminals are led out from the inside of the electric core 21 .

In the embodiment of the present application, the battery core module 20 includes one or more battery cores 21. Each battery core 21 is provided with a sub-heater 31. The sub-heater 31 generates heat after being energized to heat the battery core 21. , the temperature of the battery core 21 can be increased more quickly.

FIG. 7 is a schematic diagram of the battery core 21 provided in one embodiment of the present application, and FIG. 8 is a schematic diagram of the sub-heater 31 provided in one embodiment of the present application. As shown in Figures 7 and 8, the sub-heater 31 includes a heating piece 311 and a metal terminal 312. The heating piece 311 is electrically connected to the metal terminal 312. The heating piece 311 is disposed inside the battery core 21. The metal terminal 312 comes from the inside of the battery core 21. lead out to facilitate the electrical connection between the sub-heaters 31 and the electrical connection between the heater 30 and the battery heating circuit 10 and the cell module 20 . The battery core 21 also includes a positive terminal 211 and a negative terminal 212 .

As shown in FIG. 8 , the heating piece 311 has a sheet-like serpentine structure, and the heating piece 311 can be made of copper, aluminum or nickel.

When the ambient temperature is -20°C, the heating current is 6A to power the heating plate 311 for 240 seconds. The surface temperature rise rate of the battery core using the copper heating plate is 2.4°C/min. The surface temperature rise rate of the battery core using the aluminum heating plate The temperature rise rate is 4.0℃/min, and the surface temperature rise rate of the battery core using nickel heating plate is 6.6℃/min.

In one implementation, the battery core 21 includes a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The positive electrode, the separator, and the negative electrode are stacked and then wound on the heating sheet 311. The heating sheet 311 is wound around the battery core 21. Internally, when the heating plate 311 is energized and generates heat, the temperature of the battery core 21 can be increased faster.

Table 1 below shows the heating effect data of the two heating sheets relative to the comparative example.

Table 1

	加热片1Heating piece 1	加热片2Heating piece 2	对比例Comparative ratio
加热片位置Heating plate position	内嵌入电芯Embedded battery cell	内嵌入电芯Embedded battery cell	缠绕于电芯外Wrapped around the battery core
加热片电阻(Ω)Heating piece resistance (Ω)	13.813.8	13.213.2	15.215.2

加热电流(A)Heating current(A)	2.92.9	5.55.5	1.81.8
加热功率(W)Heating power(W)	116.1116.1	399.3399.3	49.249.2
加热速度(℃/min)Heating speed (℃/min)	11.711.7	34.834.8	3.53.5
温度均匀性temperature uniformity	☆☆☆☆☆☆	☆☆☆☆	☆☆☆☆

In the heating piece 1, heating piece 2 and the comparative example shown in Table 1 above, the weight of each heating piece is less than 0.45g, the weight of the battery core is 92g, and the energy density loss (GED loss) of the battery core where each heating piece is located Both are ≤0.5%, the thickness of heating plate 1 and heating plate 2 is less than 50 μm, and the thickness of the heating plate in the comparative example is less than 0.5mm. In the temperature uniformity index in Table 1 above, ☆ is used to indicate the temperature uniformity on the surface of the battery module. The more ☆, the better the temperature uniformity on the surface of the battery module.

From the comparison of the heating effect data of heating sheet 1, heating sheet 2 and the comparative example in Table 1, it can be seen that placing the heating sheet inside the battery core can increase the temperature rise rate of the battery core when the battery core is heated by the heating sheet.

In one implementation, the heater 30 includes at least three sub-heaters 31, and any of the following electrical connection forms are formed between each sub-heater 31:

(i) Each sub-heater 31 is electrically connected in series;

(ii) A parallel electrical connection is formed between each sub-heater 31;

(iii) A mixed electrical connection is formed between each sub-heater 31 .

The hybrid electrical connection between the sub-heaters 31 means that the first sub-heater 31 is connected in series, the remaining sub-heaters 31 are connected in series, and the first sub-heater 31 is connected to the remaining sub-heaters. The heaters 31 form a parallel electrical connection. As shown in FIGS. 2 and 3 , a mixed electrical connection is formed between each sub-heater 31 . As shown in FIG. 4 , each sub-heater 31 is electrically connected in series.

In the embodiment of the present application, when a parallel electrical connection or a mixed electrical connection is formed between each sub-heater 31, the total resistance of the heater 30 can be reduced, thereby increasing the input heating of each sub-heater under the premise that the input voltage remains unchanged. The heating current of the heater 31 allows each sub-heater 31 to increase the temperature of the battery core 21 more quickly, thereby improving the heating effect of the battery core module 20 .

The sub-heaters 31 are arranged inside the battery core 21, and a hybrid electrical connection is formed between the sub-heaters 31. The distributed power supply method can be used to supply power to each sub-heater 31, ensuring the flexibility of supplying power to the heater 31.

Battery heating method

FIG. 9 is a flow chart of a battery heating method provided by an embodiment of the present application. The battery heating method is applied to the battery pack 100 in the above embodiment. As shown in Figure 9, the battery heating method includes the following steps:

Step 901: In response to the temperature of the battery module being not lower than the temperature threshold, the controller sends a control signal to the first switch;

Step 902: The first switch is turned on in response to the received control signal, and the battery core module, the first switch and the first circuit where the heater is located are turned on, causing the temperature of the heater to rise to perform maintenance on the battery core module. heating;

Step 903: In response to the temperature of the battery module being lower than the temperature threshold, the controller sends a control signal to the second switch;

Step 904: The second switch is turned on in response to the received control signal, and the charger, the second switch and the second circuit where the heater is located are turned on, causing the temperature of the heater to rise to heat the battery module.

Since the details of the above battery heating method have been described in detail in conjunction with the structural diagram in the battery pack part of the above embodiment of the present application, the specific process can be referred to the description in the foregoing battery pack embodiment, and will not be described again here.

electronic device

One embodiment of the present application provides an electronic device, including the battery pack in the above embodiment. Electronic devices can be drones, electric two-wheelers, power tools, etc. When the electronic device is used in a lower temperature environment, it supplies power to the heater in the battery pack through the battery module or charger in the battery pack. , to heat the battery module through the heater, so that the battery module can rise to a suitable temperature in a short time, thereby improving the charging and discharging performance of the battery module in low-temperature environments, and improving the performance of electronic devices at low temperatures. environment.

It should be noted that since the heating circuit and heating method of the battery core module have been described in detail in the previous embodiments, the heating principle and heating method of the battery core module in the electronic device may refer to the description in the previous embodiment. No further details will be given.

The commercial value of the embodiments of this application

Embodiments of the present application solve the technical problem of poor charging and discharging performance of secondary batteries in low-temperature environments and easy damage to secondary batteries. When the ambient temperature is low, the temperature of the battery module is not lower than the temperature threshold when the ambient temperature is low. , the controller can send a control signal to the first switch to turn on the first switch. After the first switch is turned on, the battery module, the first switch and the first circuit where the heater is located are connected, and the battery module The group supplies power to the heater to increase the temperature of the heater to heat the battery module, so that the battery module can rise to a suitable temperature in a short time, thereby improving the performance of the battery module in low temperature environments. Charge and discharge performance.

It should be understood that each embodiment in this specification is described in a progressive manner, and the same or similar parts between various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. . In particular, for the method embodiment, since it is basically similar to the method described in the device and system embodiments, the description is relatively simple. For relevant details, please refer to the partial descriptions of other embodiments.

It should be understood that the foregoing description of specific embodiments of the present specification has been described. Other embodiments are within the scope of the claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve desired results. Additionally, the processes depicted in the figures do not necessarily require the specific order shown, or sequential order, to achieve desirable results. Multitasking and parallel processing are also possible or may be advantageous in certain implementations.

It should be understood that description herein of an element in the singular or showing only one of the elements in the drawings does not mean that the number of elements is limited to one. Furthermore, modules or elements described or shown as separate herein may be combined into a single module or element, and a module or element described or shown as a single module or element herein may be split into multiple modules or elements.

It should also be understood that the terms and expressions used herein are for description only, and one or more embodiments of this specification should not be limited to these terms and expressions. The use of these terms and expressions does not mean to exclude equivalent features of any illustrations and descriptions (or parts thereof), and it should be recognized that various possible modifications should also be included within the scope of the claims. Other modifications, changes and substitutions may exist. Accordingly, the claims should be deemed to cover all such equivalents.

Claims

A battery pack includes: a battery heating circuit, a battery core module and a heater. The battery heating circuit includes a controller and a first switch. The first switch receives a control signal from the controller to perform on or off. break;

The first switch is electrically connected to the battery core module and the heater to form a first circuit;

The first switch is configured to receive a control signal from the controller to perform conduction in response to the temperature of the battery module being not lower than a temperature threshold, so as to conduct the first circuit and enable the heater to The temperature rises to heat the battery module;

The battery core module includes at least one battery core, and the heater includes at least one sub-heater;

Wherein, the sub-heaters correspond to the battery core one-to-one, and each of the sub-heaters includes at least two metal terminals, and the metal terminals are led out from the inside of the battery core.
The battery pack according to claim 1, wherein the control end of the first switch is electrically connected to the controller for receiving a control signal from the controller;

The first end of the first switch is electrically connected to the positive electrode of the battery core module, the second end of the first switch is electrically connected to the first end of the heater, and the second end of the heater Electrically connected to the negative electrode of the battery cell module;

Alternatively, the first end of the heater is electrically connected to the positive electrode of the battery core module, the second end of the heater is electrically connected to the second end of the first switch, and the third end of the first switch is electrically connected. One end is electrically connected to the negative electrode of the battery module.
The battery pack according to claim 2, wherein the battery heating circuit further includes: a second switch and a charging port, the second switch is electrically connected to the heater and the charging port respectively, and receives the The control signal of the controller is turned on or off;

The second switch is configured to receive a control signal from the controller to perform conduction in response to the temperature of the battery module being lower than the temperature threshold, and the charging port is configured to be electrically connected to a charger, So that the charger, the second switch and the second circuit where the heater is located are turned on.
The battery pack according to claim 3, wherein the control end of the second switch is electrically connected to the controller for receiving a control signal from the controller, and the charging port includes a first charging port and a third charging port. Two charging ports;

The first end of the second switch is electrically connected to the first charging port, the second end of the second switch is electrically connected to the first end of the heater, and the second end of the heater is electrically connected to the first charging port. The second charging port is electrically connected;

Alternatively, the first end of the heater is electrically connected to the first charging port, the second end of the heater is electrically connected to the second end of the second switch, and the first end of the second switch electrically connected to the second charging port.
The battery pack according to claim 3, wherein when the first switch receives a control signal from the controller and is turned on, the second switch receives a control signal from the controller and is turned off;

Alternatively, when the second switch receives a control signal from the controller and is turned on, the first switch receives a control signal from the controller and is turned off.
The battery pack according to any one of claims 1 to 5, wherein the battery heating circuit further includes: a detector, the detector is electrically connected to the battery core module and the controller respectively. Obtaining the temperature information of the battery module and sending the temperature information to the controller;

Wherein, the detector is configured to detect the temperature of the battery core module in response to the controller waking up.
The battery pack of claim 6, wherein the controller is configured to:

Wake up in response to the power-on signal from sleep state to working state;

Or, in response to the charger accessing the charging port, receiving a charging signal and waking up.
The battery pack of claim 7, wherein the second switch is configured to receive a control signal from the controller to perform shutdown in response to a voltage of the charger being higher than a first voltage threshold.
The battery pack according to any one of claims 1-5, wherein the battery heating circuit further includes: a first diode;

The anode of the first diode is electrically connected to the anode of the battery module, and the cathode of the first diode is electrically connected to the first switch.
The battery pack according to any one of claims 3-5, wherein the battery heating circuit further includes: a second diode;

The anode of the second diode is electrically connected to the charging port, and the cathode of the second diode is electrically connected to the second switch.
The battery pack according to claim 1, wherein the heater includes more than three sub-heaters, and any of the following electrical connection forms are formed between each sub-heater:

(i) The sub-heaters are electrically connected in series;

(ii) The sub-heaters are electrically connected in parallel;

(iii) A mixed electrical connection is formed between the sub-heaters.
The battery pack according to any one of claims 1-5, wherein the battery heating circuit further includes: a third switch and a fourth switch, the third switch and the fourth switch being connected in series;

The third switch and the fourth switch are electrically connected between the positive electrode of the battery cell module and the positive output terminal of the battery cell module;

Alternatively, the third switch and the fourth switch are electrically connected between the negative electrode of the battery module and the negative output terminal of the battery module.
A battery heating method, applied to the battery pack according to any one of claims 1-12, the battery heating method includes:

In response to the temperature of the battery module not being lower than the temperature threshold, the controller sends a control signal to the first switch;

The first switch is turned on in response to the received control signal, and the battery core module, the first switch and the first circuit where the heater is located are turned on, causing the temperature of the heater to rise. The battery core module is heated;

Alternatively, in response to the temperature of the battery module being lower than the temperature threshold, the controller sends a control signal to the second switch;

The second switch is turned on in response to the received control signal, and the charger, the second switch, and the second circuit in which the heater is located are turned on, causing the temperature of the heater to rise to increase the temperature of the heater. The battery module is heated.
An electronic device including the battery pack according to any one of claims 1-12.