WO2023050458A1

WO2023050458A1 - Battery protection system

Info

Publication number: WO2023050458A1
Application number: PCT/CN2021/122763
Authority: WO
Inventors: 韦张龙
Original assignee: 深圳市飞硕科技有限公司
Priority date: 2021-09-30
Filing date: 2021-10-09
Publication date: 2023-04-06

Abstract

Provided is a battery protection system, which is applied to the technical field of battery management. The battery protection system comprises a battery pack (10), a control unit (20) and a heating module (30), wherein the control unit (20) is connected to the battery pack (10), and acquires the temperature of the battery pack (10) in real time; when the temperature of the battery pack (10) is lower than a first preset value, a control instruction is sent to the heating module (30), such that the heating module (30) is controlled to heat the battery pack (10); and when the temperature of the battery pack (10) rises to a second preset value, the heating module (30) is controlled to stop a heating operation. The current temperature of the battery pack (10) is acquired by means of the control unit (20); when the current temperature of the battery pack (10) is lower than the first preset value, the battery pack (10) is heated by means of the heating module (30); and when the temperature of the battery pack (10) rises to the second preset value, heating can be stopped. In this way, the battery pack (10) can be effectively prevented from operating in a low-temperature state, and a battery can be effectively prevented from being heated to an excessively high temperature, which causes damage to the battery, thereby prolonging the service life of the battery.

Description

A battery protection system

technical field

The utility model belongs to the technical field of battery management, in particular to a battery protection system.

Background technique

At present, when using a lithium battery, it is usually necessary to charge the lithium battery for recycling.

However, at present, when the lithium battery is in a running state, such as charging, discharging, standby, etc., the current temperature of the lithium battery is often unable to be determined, and it is used directly. For example, when charging, it is directly connected to the power supply to charge the battery. As a result, under low temperature conditions, such as zero degrees and below, when charging lithium batteries, there will be problems such as failure to charge or insufficient charge, resulting in battery damage or reduced battery life.

Utility model content

The utility model provides a battery protection system, which aims to solve the problem of battery damage and reduced battery life in the existing charging method.

The utility model is achieved in this way, a battery protection system, comprising:

battery pack, control unit and heating module;

The control unit is connected to the battery pack, and obtains the temperature of the battery pack in real time, and sends a control instruction to the heating module to control the temperature of the battery pack when the temperature of the battery pack is lower than a first preset value. The heating module heats the battery pack until the temperature of the battery pack is heated to a second preset value, and the heating module is controlled to stop the heating operation.

In one embodiment, the battery protection system includes:

A bluetooth module connected with the control unit, the bluetooth module is connected with the mobile terminal, so that the mobile terminal monitors the operating state of the battery pack.

In one embodiment, the battery protection system includes:

a fuel gauge connected to the control unit, the fuel gauge is used to detect the current power of the battery pack;

The power display device connected to the control unit is used to display the current power of the battery pack detected by the fuel gauge.

In one embodiment, the battery protection system includes:

A balance module, one end of the balance module is connected to the battery pack, and the other end of the balance module is connected to the control unit.

In one embodiment, the balancing module includes:

an equalizing circuit connected to the battery pack for equalizing charging of the battery pack; and

A current amplifier, one end of the current amplifier is connected to the equalization circuit, and the other end of the current amplifier is connected to the control unit.

In one embodiment, the heating module includes:

a heating power control module connected to the control unit; and

A heating device connected to the heating power control module.

In one embodiment, the battery protection system includes:

An environmental temperature detection device, the environmental temperature detection device is connected to the control unit, and sends the detected environmental temperature to the control unit, so that the control unit controls the heating module to the control unit according to the environmental temperature The battery pack is heating up.

In one embodiment, the battery protection system further includes:

a pre-discharge module, configured to reduce the voltage of the battery pack to a preset voltage value;

The pre-charging module is used for pre-charging the battery pack before the constant charging of the battery pack.

In one embodiment, the battery protection system further includes:

The historical data recording unit is used to record the highest voltage data, the lowest voltage data and the overcurrent data during the use of the battery pack, so as to determine whether the battery pack is in a normal state.

In one embodiment, the heating device is disposed on the surface of the battery pack or between the single cells. .

The embodiment of the utility model provides a battery protection system, including: a battery pack, a control unit and a heating module; the control unit is connected to the battery pack, and obtains the temperature of the battery pack in real time, when the temperature of the battery pack is lower than When the first preset value is reached, send a control command to the heating module to control the heating module to heat the battery pack until the temperature of the battery pack is heated to the second preset value, then control the The heating block stops heating operation. Obtain the current temperature of the battery pack through the control unit, and when the current temperature of the battery pack is lower than the first preset value, heat the battery pack through the heating module, and when the temperature of the battery pack is heated to the second preset value, Stopping the heating can effectively prevent the battery pack from working in a low temperature state, and can effectively prevent the battery from being heated too high, causing the battery to be damaged, and can improve the service life of the battery.

Description of drawings

Fig. 1 is a schematic diagram of modules of a battery protection system provided by an embodiment of the present invention;

Fig. 2 is a schematic diagram of modules of another battery protection system provided by an embodiment of the present invention;

Fig. 3 is a schematic diagram of a battery capacity display module provided by an embodiment of the utility model;

Fig. 4 is a schematic diagram of a balance module provided by an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

Referring to Fig. 1, in an embodiment of the present invention, a battery protection system is provided, including: a battery pack 10, a control unit 20, and a heating module 30; the control unit 20 is connected to the battery pack 10, and obtains real-time The temperature of the battery pack 10, when the temperature of the battery pack 10 is lower than a first preset value, send a control command to the heating module 30 to control the heating module 30 to heat the battery pack 10 , until the temperature of the battery pack 10 is heated to a second preset value, the heating module 30 is controlled to stop the heating operation. Obtain the current temperature of the battery pack through the control unit, and when the current temperature of the battery pack is lower than the first preset value, heat the battery pack through the heating module, and when the temperature of the battery pack is heated to the second preset value, Stopping the heating can effectively prevent the battery pack from working in a low temperature state, and can effectively prevent the battery from being heated too high, causing the battery to be damaged, and can improve the service life of the battery.

In an implementation scenario of the present invention, when the battery pack 10 is in the charging state, the control unit 20 acquires the current temperature of the battery pack 10, and stops the charging operation when the current temperature of the battery pack 10 is lower than the first preset value, And control the heating module 30 to heat the battery pack 10 until the temperature of the battery pack 10 reaches the second preset value, then control the heating module 30 to stop the heating operation and resume the charging operation.

In an implementation scenario of the present invention, when the battery pack 10 is in the charging state, the control unit 20 acquires the current temperature of the battery pack 10, and when the current temperature of the battery pack 10 is lower than the first preset value, controls the heating module 30 Heat the battery pack 10 until the temperature of the battery pack 10 reaches a second preset value, control the heating module 30 to stop the heating operation, and continue to perform the charging operation during the heating process of the battery pack 10 by the heating module 30, Specifically, the balance compensation algorithm can be used to perform constant temperature control and energy saving, so that the battery pack 10 is always in the optimal charging state, the charging speed is faster, and there is no need to wait for heating, which is beneficial to improving the service life of the battery pack 10 .

Further, after the heating is stopped, the temperature of the battery pack 10 can be measured in real time. When it is detected that the temperature of the battery pack 10 is lower than the first preset value, the above heating operation is performed here until the charging of the battery pack 10 is completed.

In an implementation scenario of the present invention, when the battery pack 10 is in a standby state or a discharging state, the current temperature of the battery pack 10 is obtained in real time through the control unit 20, and when the current temperature of the battery pack 10 is lower than the first preset value, the control unit 20 The heating module 30 heats the battery pack 10 until the temperature of the battery pack 10 reaches a second preset value, and then controls the heating module 30 to stop the heating operation, so that the battery pack 10 is always kept in an optimal working state, preventing the battery pack 10 from Sustained low temperature, resulting in abnormal use or storage capacity.

In an embodiment of the present invention, when the heating module 30 is heating, it is necessary to obtain a preset temperature compensation value, and adjust the first preset value and the second preset value according to the temperature compensation value. During the charging and discharging process of the battery pack 10, the battery pack 10 itself will generate some heat, so the preset temperature compensation value is the heat value generated by the battery pack 10 itself, which can avoid the battery pack from overheating and the like.

Wherein, the battery pack 10 may be a lithium battery pack, such as a lithium iron phosphate battery. When the lithium battery is charged below zero, the internal material of the lithium battery will crystallize, and the crystal will pierce the inside of the battery, resulting in attenuation of battery capacity, damage to the battery, or reduction in battery life. Therefore, in this application, the heating module 30 will When the temperature of the battery pack 10 is lower than the first preset value, recharging after heating can stabilize the internal chemical properties of the battery, protect the battery capacity, and increase the service life of the battery.

Wherein, the control unit 20 can be arranged on a battery protection board, and the battery protection board can be a BMS (Battery Protection Management System) battery protection board.

Wherein, the heating temperature of the heating module 30 may be -20° to 10°.

Wherein, the first preset value may be zero degrees, and the second preset value may be 10°.

Referring to FIG. 2 , in an embodiment of the present invention, the heating module 30 includes: a heating power control module 31 connected to the control unit 20 ; and a heating device 32 connected to the heating power control module 31 . The control unit 20 can control the heating temperature of the heating device 32 through the heating power control module 31 , for example, stop heating when the temperature of the battery pack 10 rises to a second preset value.

Wherein, the heating device 32 may be a heating sheet or a heating film, such as a silicone electric heating sheet, a PTC heating sheet, or the like.

In an embodiment of the present invention, the heating device 32 can be disposed on the surface of the battery pack 10 or between the single cells. Specifically, the heating device 32 can be pasted on the surface of the battery pack 10 so as to heat the battery pack 10 .

Wherein, the heating device 32 is different according to the assembly shape of the battery pack 10 .

In the embodiment of the present application, the control unit 20 can be a single-chip microcomputer, which has a host computer software for computer-side monitoring, and has an isolated RS-232/isolated RS-485/isolated RS-422/isolated isolated UART interface And isolated CAN communication interface, non-isolated system management bus (SMBUS), so as to connect with the computer. And the control unit is connected with the battery pack 10, and can read the voltage of each single cell in the battery pack 10, the capacity of the entire battery pack 10, the number of charge and discharge cycles, the temperature of the battery pack, the battery state of health (SOH), the battery SOC, etc.

Among them, the single-chip microcomputer has an isolated RS-232 communication interface, so no adapter board is needed, and only an isolated RS-232 communication interface to USB conversion cable can be connected to the USB interface on the computer side. Realize the communication with the computer, so that the state of the battery pack can be monitored through the computer.

Among them, the single-chip microcomputer is a low-power single-chip microcomputer with an industrial grade of 40-85 degrees.

Wherein, referring to FIG. 2 , the control unit 20 also includes a mechanical control interface for mechanical control.

In an embodiment of the present invention, the battery protection system further includes: a temperature detection device 60 communicatively connected with the control unit 20 , the temperature detection device 60 is arranged on the battery pack 10 so as to detect the temperature of the battery pack 10 . The control unit 20 acquires the temperature of the battery pack 10 detected by the temperature detection device 60, and when charging, when the temperature of the battery pack is low, heats the battery pack 10 through the heating module 30,

Wherein, the temperature control device 60 can be an NTC temperature sensor, and the NTC temperature sensor can be 4 channels, referring to FIG. 2 , which can include NTC1, NTC2, NTC3 and NTC4.

In an embodiment of the present invention, the battery protection system further includes: an ambient temperature detection device, which is connected to the control unit 20 and sends the detected ambient temperature to the control unit 20, so that The control unit 20 controls the heating module 30 to heat the battery pack 10 according to the ambient temperature. Specifically, when the battery pack 10 is in a low-temperature environment, in order to prevent the battery pack 10 from being on standby at a low temperature, due to the influence of the ambient temperature, the temperature of the battery pack 10 continues to be in a low-temperature state, resulting in failure to perform normal discharge and attenuation of battery capacity. . Therefore, the ambient temperature at the current location of the battery pack 10 is detected by the ambient temperature detection device. When the ambient temperature is too low, the battery pack 10 can be heated by the heating module 10, so that the battery pack 10 is always in a constant temperature state. Thereby improving the service life of the battery.

In an embodiment of the present utility model, the battery protection system further includes: a Bluetooth module 21 connected to the control unit 20, and the Bluetooth module 21 is connected to a mobile terminal so that the mobile terminal monitors the battery pack 10 operating status. Specifically, a pre-written application program is installed in the mobile terminal, and the control unit 20 can transmit information such as the obtained battery temperature, battery capacity, and battery remaining power to the mobile terminal through the Bluetooth module 21, and the application program installed in the mobile terminal can , to display the above information of the battery pack 10, so that the user can know the current state of the battery in time, and carry out risk control in time.

Referring to FIG. 3, in an embodiment of the present invention, the system further includes: a fuel gauge 22 connected to the control unit 20, the fuel gauge 22 is used to detect the current power of the battery pack 10; The power display device 23 connected to the control unit 20 is used to display the current power of the battery pack 10 detected by the fuel gauge 22 . In order to keep abreast of the remaining power situation of the battery pack 10 and the charging situation, avoid the situation that the battery is fully charged but still continues to charge, and can know at any time whether the battery has the situation of being unable to charge or charging slowly, so as to timely carry out deal with.

Wherein, the fuel gauge 22 may have a temperature compensation function to improve the power detection accuracy, such as MAX17047.

In an embodiment of the present invention, the power display device 23 can display the current remaining power of the battery pack 10 , for example, it can be an LED power display device or an LCD power display device.

In one embodiment of the present invention, when the LED power display device is used for power display, when there is a charging current greater than 200 mA, the power display area will automatically light up, and when there is no charging current, the power will be automatically turned off. In the display area, if you need to display the power during discharge, you can press the preset light touch switch to start the power display area to display the power, and the power will be displayed for 5 seconds and then automatically shut down to achieve the purpose of saving power. When the LCD display device is performing power display, no matter charging or discharging, the power can always be displayed in the display area of the LCD display device, so as to check the current power of the battery at any time.

In an embodiment of the present invention, the power display device 23 also includes a plurality of display lights, which are respectively used to display the power of the battery pack 10 detected by the fuel gauge, the fault display light and the operating status display light Etc., the fuel gauge lights can include multiple, for example, 4, when the battery pack 10 is 25%, one fuel gauge light is turned on, and when the power is 50%, two fuel gauge lights are turned on, and Different colors can be used to represent different meanings, for example, when the fault display light is red, it means that there is a fault, etc.

In an embodiment of the present invention, the balance module 40 connected to the battery pack 10, one end of the balance module 40 is connected to the battery pack 10, and the other end of the balance module 10 is connected to the The control unit 20 is connected. By setting the balancing module 40 between the control unit 20 and the battery pack 10, each battery in the battery pack 10 can be charged in a balanced manner, and uneven charging can be avoided.

Referring to FIG. 4 , in an embodiment of the present invention, the balancing module 40 includes: a balancing circuit 41 connected to the battery pack 10 to charge the battery pack 10 in a balanced manner; The control unit 20 is connected to a current amplifier 42 .

Wherein, the equalization circuit 41 can be a passive equalization circuit, which can prevent the equalization circuit 40 from overheating.

Referring to FIG. 2 , in an embodiment of the present invention, the battery protection system further includes a charge and discharge power control module 50, one end of the charge and discharge control power module 50 is connected to the control unit 20, and the charge and discharge control power module 50 The other end of the battery pack is connected to the battery pack 10 so as to control the charging and discharging power of the battery pack 10 under the control of the control unit 20 to avoid over-current and over-discharge.

In an implementation scenario, for example, when the battery pack 10 is over-discharged, it can recover to the over-discharge recovery voltage within a preset time after the battery pack 10 is over-discharged, such as 10 seconds, and enter the power-off shutdown state. Draws less than 15 microamps and requires a charger to activate.

Further, after the battery pack 10 has over-discharge or over-current for a preset period of time, for example, 30 seconds, the function can be restored without disconnecting the load. When overload and short circuit occur, it is necessary to disconnect the load.

In an embodiment of the present invention, the battery protection system further includes a DC-DC converter, one end of the DC-DC converter is connected to the charging and discharging power control module 50, and the other end of the DC-DC converter is connected to the control module 50. Unit 20 is connected.

In an embodiment of the present invention, the battery protection system further includes a pre-discharge module, used to reduce the voltage of the battery pack to a preset voltage value; a pre-charge module, used to charge the battery pack before constant charging The battery pack is precharged. It can effectively reduce sparks when connecting.

Wherein, one end of the pre-discharge module can be connected with the control unit 20 , and the other end can be connected with the battery pack 10 . One end of the pre-charging module can be connected to the control unit 20 , and the other end can be connected to the battery pack 10 .

In an embodiment of the present invention, the battery protection system further includes: a historical data recording unit, which is used to record the highest voltage data, the lowest voltage data and the overcurrent data during the use of the battery pack 10, so as to determine whether the battery pack 10 is in normal status.

Wherein, the historical data recording unit is also used for recording the charging record and discharging record of the battery pack 10, wherein, the charging record will be regarded as a charge only if the charging record is continuously charged above 90% until it is fully charged, and the current is greater than 500 milliamperes. The discharge recording should stop after discharging more than 90% of the electricity, and then start recording this discharge. It can effectively prevent non-stop intermittent discharge and record too many problems.

In an embodiment of the utility model, the battery protection system also includes a charging and discharging temperature protection module, which protects the charging high temperature, charging low temperature, discharging high temperature, and discharging low temperature. For example, when the temperature of the battery pack 10 reaches 55° during charging, it can Protection is performed until the temperature of the battery pack 10 returns to a normal level, such as 50°. Further, a time-delay protection function can be set, for example, protection will be performed after reaching a preset time, such as 5 seconds.

In an embodiment of the utility model, the battery protection system further includes: a weak current protection switch, which can independently control the discharge circuit without a large current control unit, which can effectively save costs and prolong the life of components.

In an embodiment of the present invention, the battery protection system further includes: a sleep switch, which is connected to the control unit 20 and can control the battery to enter a sleep state when the battery is not in use.

In an embodiment of the present invention, the battery protection system further includes: a secondary protection function and a permanent battery failure protection function to ensure that the battery is safe at any time. Among them, the secondary protection function is only valid for continuous current less than 30A.

In an embodiment of the utility model, the battery protection system further includes a sampling module for sampling current and voltage. The sampling module can be a 16-bit acquisition chip to improve sampling accuracy.

In an embodiment of the present invention, the above-mentioned battery protection system can be applied to various lithium battery devices, such as lithium battery electric bicycles, lithium battery electric motorcycles, lithium battery low-speed vehicles, lithium battery solar energy, lithium battery electric RVs, household lithium battery solar energy and other lithium battery equipment.

In the embodiment of the present invention, the current temperature of the battery pack is obtained by the control unit, and when the current temperature of the battery pack is lower than the first preset value, the battery pack is heated by the heating module, and the temperature of the battery pack can be heated to When the second preset value is reached, heating is stopped, which can effectively prevent the battery pack from working in a low temperature state, and can effectively avoid heating the battery to an excessively high temperature, causing the battery to be damaged, thereby improving the service life of the battery.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in this utility model. within the scope of protection of utility models.

Claims

A battery protection system, characterized in that the system includes:

battery pack, control unit and heating module;

The control unit is connected to the battery pack, and obtains the temperature of the battery pack in real time, and sends a control instruction to the heating module to control the temperature of the battery pack when the temperature of the battery pack is lower than a first preset value. The heating module heats the battery pack until the temperature of the battery pack is heated to a second preset value, and the heating module is controlled to stop the heating operation.
The battery protection system according to claim 1, wherein the system comprises:

A bluetooth module connected with the control unit, the bluetooth module is connected with the mobile terminal, so that the mobile terminal monitors the operating state of the battery pack.
The battery protection system according to claim 1, wherein the system comprises:

a fuel gauge connected to the control unit, the fuel gauge is used to detect the current power of the battery pack;

The power display device connected to the control unit is used to display the current power of the battery pack detected by the fuel gauge.
The battery protection system according to claim 1, wherein the system comprises:

A balance module, one end of the balance module is connected to the battery pack, and the other end of the balance module is connected to the control unit.
The battery protection system according to claim 4, wherein the balancing module comprises:

an equalizing circuit connected to the battery pack for equalizing charging of the battery pack; and

A current amplifier, one end of the current amplifier is connected to the equalization circuit, and the other end of the current amplifier is connected to the control unit.
The battery protection system according to claim 1, wherein the system comprises:

An environmental temperature detection device, the environmental temperature detection device is connected to the control unit, and sends the detected environmental temperature to the control unit, so that the control unit controls the heating module to the control unit according to the environmental temperature The battery pack is heating up.
The battery protection system according to claim 1, wherein the heating module comprises:

a heating power control module connected to the control unit; and

A heating device connected to the heating power control module.
The battery protection system according to claim 1, wherein the system comprises:

a pre-discharge module, configured to reduce the voltage of the battery pack to a preset voltage value;

The pre-charging module is used for pre-charging the battery pack before the constant charging of the battery pack.
The battery protection system according to claim 1, wherein the system comprises:

The historical data recording unit is used to record the highest voltage data, the lowest voltage data and the overcurrent data during the use of the battery pack, so as to determine whether the battery pack is in a normal state.
The battery protection system according to claim 7, wherein the heating device is arranged on the surface of the battery pack or between the single cells.