CN105703025A - Battery module discharge method and device for on-board rechargeable energy storage system - Google Patents

Abstract

The embodiment of the invention discloses a battery module discharging method and device for a vehicle-mounted rechargeable energy storage system. The method includes: detecting the temperature value of the battery module and the temperature value outside the vehicle; when the temperature value of the battery module is higher than the preset low temperature threshold value of the battery module When the ambient temperature outside the vehicle is higher than the preset ambient low temperature threshold and lower than the preset ambient high temperature threshold, the battery module is enabled to discharge at full power. The embodiments of the present invention limit the discharge capacity of the battery module under extreme conditions by detecting the temperature of the battery module and the ambient temperature, thereby ensuring the service life of the battery module.

Description

A battery module discharge method and device for a vehicle-mounted rechargeable energy storage system

technical field

The invention relates to the technical field of automobiles, and more specifically, to a method and device for discharging a battery module of a vehicle-mounted rechargeable energy storage system.

Background technique

Energy shortages, oil crises and environmental pollution are intensifying, which have a huge impact on people's lives and are directly related to the sustainable development of the country's economy and society. All countries in the world are actively developing new energy technologies. As a new energy vehicle with reduced oil consumption, low pollution, and low noise, electric vehicles are considered to be an important way to solve the energy crisis and environmental degradation. Hybrid vehicles take into account the advantages of pure electric vehicles and traditional internal combustion engine vehicles at the same time. On the premise of meeting the requirements of vehicle power and mileage, it effectively improves fuel economy and reduces emissions. It is considered to be the current energy-saving and emission reduction one of the valid paths.

In current EVs, the battery management system performs battery thermal management for the battery modules. The on-board rechargeable energy storage system (Rechargeable Energy Storage System, RESS) is an energy storage system that is rechargeable and can provide electric energy. The RESS system can improve battery safety and reduce costs.

In the thermal management discharge control program of the current vehicle-mounted RESS system, the discharge power of the battery module is only controlled based on the internal temperature of the battery module. FIG. 1 is a schematic diagram of thermal management discharge control in the prior art. It can be seen from Figure 1 that in the prior art, as long as the internal temperature of the battery module is between the low temperature threshold value A and the high temperature threshold value B, the battery module group can be discharged at full power without considering the influence of the ambient temperature .

However, the battery module is also affected by the ambient temperature in actual use. Under extreme ambient temperature, if the discharge capacity of the battery module is not limited in advance, it is likely to affect the service life of the battery module.

Contents of the invention

The object of the present invention is to provide a battery module discharge method and device for a vehicle-mounted rechargeable energy storage system, thereby improving the service life of the battery module.

In an embodiment of the present invention, a method for discharging a battery module of a vehicle-mounted rechargeable energy storage system includes:

Detect the temperature value of the battery module and the temperature value outside the vehicle;

When the temperature value of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is higher than the preset When the ambient low temperature threshold is lower than the preset ambient high temperature threshold, the battery module is enabled to discharge with full power.

Preferably, the method also includes:

When the ambient temperature outside the vehicle is lower than the ambient low temperature threshold, the battery module is enabled to discharge with limited power.

Preferably, the method also includes:

When the ambient temperature outside the vehicle is higher than the ambient high temperature threshold, the battery module is enabled to discharge with limited power.

Preferably, the method also includes:

When the temperature value of the battery module is lower than the low temperature threshold of the battery module, the power-limited discharge of the battery module is enabled.

Preferably, the method also includes:

When the temperature value of the battery module is higher than the high temperature threshold of the battery module, the power-limited discharge of the battery module is enabled.

In an embodiment of the present invention, a battery module discharge device for a vehicle-mounted rechargeable energy storage system includes:

The battery module temperature detection module is used to detect the temperature value of the battery module;

The temperature detection module outside the vehicle is used to detect the temperature value of the environment outside the vehicle;

The discharging module is used for when the temperature value of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is high When the preset ambient low temperature threshold is lower than the preset ambient high temperature threshold, the battery module is enabled to discharge at full power.

Preferably, the discharge module is further configured to enable power-limited discharge of the battery module when the ambient temperature outside the vehicle is lower than the ambient low temperature threshold.

Preferably, the discharge module is further configured to enable power-limited discharge of the battery module when the ambient temperature outside the vehicle is higher than the ambient high temperature threshold.

Preferably, the discharge module is further configured to enable power-limited discharge of the battery module when the temperature value of the battery module is lower than the low temperature threshold of the battery module.

Preferably, the discharge module is further configured to enable power-limited discharge of the battery module when the temperature of the battery module is higher than the high temperature threshold of the battery module.

It can be seen from the above technical solutions that in the embodiment of the present invention, the temperature value of the battery module and the temperature value outside the vehicle are detected; when the temperature value of the battery module is higher than the low temperature threshold of the battery module and lower than the high temperature threshold, and the ambient temperature outside the vehicle is higher than the ambient low temperature threshold and lower than the ambient high temperature threshold, the battery module will be discharged at full power; otherwise, the battery module will be discharged with limited power. It can be seen that the embodiment of the present invention controls the discharge power of the battery module based on the temperature of the battery module and the ambient temperature at the same time, and limits the discharge capacity of the battery module in advance before the extreme ambient temperature affects the battery module, thus ensuring the use of the battery module. life.

Description of drawings

The following drawings only illustrate and explain the present invention schematically, and do not limit the scope of the present invention.

FIG. 1 is a schematic diagram of thermal management discharge control in the prior art.

Fig. 2 is a flowchart of a battery module discharging method of a vehicle-mounted rechargeable energy storage system according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of logical processing of a battery module discharging method of a vehicle-mounted rechargeable energy storage system according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of discharging control of a battery module according to an embodiment of the present invention.

Fig. 5 is a structural diagram of a battery module discharge device of a vehicle-mounted rechargeable energy storage system according to an embodiment of the present invention.

detailed description

In order to have a clearer understanding of the technical features, purposes and effects of the invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings, in which the same reference numerals represent the same parts.

For the sake of brevity and intuition in description, the solution of the present invention is described below by describing several representative implementation manners. Numerous details in the embodiments are only used to help the understanding of the solutions of the present invention. But obviously, the technical solutions of the present invention may not be limited to these details when implemented. In order to avoid unnecessarily obscuring the solution of the present invention, some embodiments are not described in detail, but only a framework is given. Hereinafter, "including" means "including but not limited to", and "according to..." means "at least according to, but not limited to only based on...". Due to the language habits of Chinese, when the quantity of a component is not specifically indicated below, it means that the component can be one or more, or can be understood as at least one.

The applicant found that the battery module is affected by the ambient temperature in actual use. Under extreme ambient temperature, there will be a large temperature difference inside the battery module, which will affect the service life of the battery module. In view of the defects existing in the prior art, the embodiment of the present invention controls the discharge power of the battery module based on the temperature of the battery module and the ambient temperature at the same time, thereby limiting the discharge capacity of the battery module under extreme environmental conditions, so as to ensure that the battery module service life.

Fig. 2 is a flowchart of a battery module discharging method of a vehicle-mounted rechargeable energy storage system according to an embodiment of the present invention.

As shown in Figure 2, the method includes:

Step 201: Detect the temperature value of the battery module and the temperature value outside the vehicle.

Here, the battery module temperature sensor and the outside environment temperature sensor can be set separately. The battery module temperature sensor is used to detect the internal temperature value of the battery module, and the outside environment temperature sensor is used to detect the outside environment temperature value of the car.

Regardless of whether it is the temperature detection of the battery module or the ambient temperature outside the vehicle, various temperature sensors can be used in the embodiments of the present invention. For example, according to the measurement method, it can be divided into two categories: contact temperature sensor and non-contact temperature sensor; according to the characteristics of sensor materials and electronic components, it can be divided into thermal resistance temperature sensor and thermocouple temperature sensor. Specifically, the temperature sensor may use a thermocouple, a thermistor, a platinum resistance thermometer (RTD), a temperature detection integrated circuit, and the like.

The temperature sensor that can be used in the embodiments of the present invention is described in detail above, and those skilled in the art can realize that this description is only exemplary, and is not intended to limit the protection scope of the embodiments of the present invention.

Step 202: Determine whether the temperature of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is higher than the preset When the ambient low temperature threshold is lower than the preset ambient high temperature threshold, if yes, go to step 203 , otherwise go to step 204 .

The invention presets the low temperature threshold value of the battery module, the high temperature threshold value of the battery module, the low temperature threshold value of the environment and the high temperature threshold value of the environment.

When the temperature value of the battery module is higher than the low temperature threshold of the battery module and lower than the high temperature threshold of the battery module, it can be determined that the internal temperature of the battery module is within a normal range. When the ambient temperature outside the vehicle is higher than the ambient low temperature threshold and lower than the ambient high temperature threshold, it can be determined that the ambient temperature outside the vehicle is within a normal range.

After it is determined that the internal temperature of the battery module is within the normal range, the ambient temperature outside the vehicle is further compared with the ambient low temperature threshold and the ambient high temperature threshold. Only when it is further determined that the ambient temperature outside the vehicle is within the normal range, that is, the internal temperature of the battery module and the ambient temperature outside the vehicle are both normal, step 203 is executed; otherwise, step 204 is executed.

Step 203: Enable the battery module to discharge at full power, and end this process.

Here, when it is determined in step 202 that both the internal temperature of the battery module and the ambient temperature outside the vehicle are normal, the battery module is enabled to discharge at full power. In full power discharge, the battery module can perform discharge according to the rated full power. Depending on the specific model of the battery module, the specific parameters of full power discharge may be different, which will not be repeated in the present invention.

Step 204: Enable power-limited discharge of the battery module, and end this process.

Here, when it is determined in step 202 that at least one of the internal temperature of the battery module and the ambient temperature outside the vehicle is abnormal, the present invention does not enable the full power discharge of the battery module, but enables the limited power discharge of the battery module. . In power-limited discharge, the battery module does not perform discharge according to the rated full power, but performs discharge below the rated full power. For example, discharge may be performed at half the rate of full power discharge. For example, when the full power discharge of the battery module is 10C, the power discharge of the battery module can be limited to 5C.

It can be seen that even if the internal temperature of the battery module is normal, as long as the ambient temperature outside the vehicle is abnormal, the embodiment of the present invention does not allow the battery module to discharge at full power, but limits the battery module to discharge at limited power. Therefore, the present invention can prolong the service life of the battery module by limiting the discharge capacity of the battery module under extreme ambient temperature. The battery module discharge process may include driving a motor or discharging a charger, and so on. The present invention is not limited thereto.

Specifically: the specific situation of battery module power-limited discharge includes at least one of the following:

(1) When the ambient temperature outside the vehicle is lower than the ambient low temperature threshold, the battery module is enabled to discharge with limited power.

(2) When the ambient temperature outside the vehicle is higher than the ambient high temperature threshold, the battery module is enabled to discharge with limited power.

(3) When the temperature value of the battery module is lower than the low temperature threshold value of the battery module, the power-limited discharge of the battery module is enabled.

(4) When the temperature value of the battery module is higher than the high temperature threshold of the battery module, the power-limited discharge of the battery module is enabled.

Based on the above description, FIG. 3 is a schematic diagram of logical processing of a battery module discharging method of a vehicle-mounted rechargeable energy storage system according to an embodiment of the present invention.

In FIG. 3 , the high temperature threshold value A of the battery module and the low temperature threshold value B of the battery module are preset. For example, the high temperature threshold A of the battery module may be 40 degrees; the low temperature threshold B of the battery module may be 0 degrees. Moreover, the ambient low temperature threshold value C and the ambient high temperature threshold value D are preset. For example, the ambient low temperature threshold C is -10 degrees, and the ambient high temperature threshold D is 50 degrees. Moreover, it is assumed that the full power discharge of the battery module is 10C.

When the temperature of the battery module is higher than 40 degrees, discharge the battery module with limited power. For example, when the temperature of the battery module is 50 degrees, the discharge rate is reduced to 5C.

When the temperature of the battery module is lower than 0 degrees, discharge the battery module with limited power. For example, when the temperature of the battery module is -3 degrees, the discharge rate is reduced to 5C.

When the ambient temperature outside the vehicle is higher than 50 degrees, perform power-limited discharge on the battery module. For example, when the ambient temperature outside the car is 55 degrees, the discharge rate is reduced to 5C.

When the ambient temperature outside the vehicle is lower than -10 degrees, perform power-limited discharge on the battery module. For example, when the ambient temperature outside the car is -12 degrees, the discharge rate is reduced to 5C.

When the temperature of the battery module is higher than 0°C and lower than 40°C, if the ambient temperature outside the vehicle is higher than 50°C, discharge the battery module with limited power. For example, when the temperature of the battery module is 20 degrees and the ambient temperature outside the vehicle is 55 degrees, the discharge rate is reduced to 5C.

When the temperature of the battery module is higher than 0°C and lower than 40°C, if the ambient temperature outside the vehicle is lower than -10°C, discharge the battery module with limited power. For example, when the temperature of the battery module is 20 degrees and the ambient temperature outside the vehicle is -15 degrees, the discharge rate is reduced to 5C.

When the temperature of the battery module is higher than 0°C and lower than 40°C, if the ambient temperature outside the vehicle is higher than -10°C and lower than 50°C, perform full power discharge on the battery module. For example, when the temperature of the battery module is 20 degrees and the ambient temperature outside the vehicle is 20 degrees, the discharge rate is 10C.

The embodiments of the present invention are described above with specific temperature values and discharge rate values. Those skilled in the art can realize that this description is only exemplary and is not intended to limit the protection scope of the present invention.

FIG. 4 is a schematic diagram of a battery module discharge control according to an embodiment of the present invention. It can be seen from Fig. 4 that, unlike the prior art, the embodiment of the present invention requires the internal temperature of the battery module to be between the low temperature threshold value A and the high temperature threshold value B, and the ambient temperature to be between the low temperature threshold value C and the high temperature threshold value. Between the value D, the battery module can be discharged at full power.

It can be seen that the embodiments of the present invention control the discharge power of the battery module based on both the temperature of the battery module and the ambient temperature, thereby limiting the discharge capacity of the battery module under extreme environmental conditions and ensuring the service life of the battery module.

Based on the above description, the present invention also proposes a battery module discharge device for a vehicle-mounted rechargeable energy storage system.

Fig. 5 is a structural diagram of a battery module discharge device of a vehicle-mounted rechargeable energy storage system according to the present invention.

As shown in Figure 5, the device 500 includes:

The battery module temperature detection module 501 is used to detect the temperature value of the battery module;

The ambient temperature detection module 502 outside the vehicle is used to detect the ambient temperature value outside the vehicle;

Discharging module 503, used for when the temperature of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is higher than the preset When the ambient low temperature threshold is lower than the preset ambient high temperature threshold, the battery module is enabled to discharge at full power.

In one embodiment, the discharge module 503 is further configured to enable the battery module to discharge with limited power when the ambient temperature outside the vehicle is lower than the ambient low temperature threshold.

In one embodiment, the discharge module 503 is further configured to enable the battery module to discharge with limited power when the ambient temperature outside the vehicle is higher than the ambient high temperature threshold.

In one embodiment, the discharging module 503 is further configured to enable power-limited discharge of the battery module when the temperature of the battery module is lower than the low temperature threshold of the battery module.

In one embodiment, the discharge module 503 is further configured to enable power-limited discharge of the battery module when the temperature of the battery module is higher than the high temperature threshold of the battery module.

The battery module discharge method and device of the on-board rechargeable energy storage system proposed in the embodiment of the present invention can be applied to various types of new energy vehicles, including pure electric vehicles (BEV), hybrid electric vehicles (PHEV) or fuel cells Automotive (FCEV), etc.

To sum up, in the embodiment of the present invention, the temperature value of the battery module and the temperature value outside the vehicle are detected; when the temperature value of the battery module is higher than the low temperature threshold of the battery module and lower than the high temperature threshold of the battery module , and the ambient temperature outside the vehicle is higher than the ambient low temperature threshold and lower than the ambient high temperature threshold, the battery module is discharged at full power, otherwise the battery module is discharged at limited power. It can be seen that the embodiment of the present invention controls the discharge power of the battery module based on the temperature of the battery module and the ambient temperature at the same time, and limits the discharge capacity of the battery module in advance before the ambient temperature affects the battery module, thereby ensuring the service life of the battery module .

The series of detailed descriptions listed above are only specific descriptions of the feasible implementation modes of the present invention, and are not intended to limit the protection scope of the present invention. Any equivalent implementation or Changes, such as combination, division or repetition of features, should be included in the protection scope of the present invention.

Claims (10)

1. A method for discharging a battery module of a vehicle-mounted rechargeable energy storage system, characterized in that it comprises: Detect the temperature value of the battery module and the temperature value outside the vehicle; When the temperature value of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is higher than the preset When the ambient low temperature threshold is lower than the preset ambient high temperature threshold, the battery module is enabled to discharge with full power. 2. The method according to claim 1, characterized in that the method further comprises: When the ambient temperature outside the vehicle is lower than the ambient low temperature threshold, the battery module is enabled to discharge with limited power. 3. The method according to claim 1, characterized in that the method further comprises: When the ambient temperature outside the vehicle is higher than the ambient high temperature threshold, the battery module is enabled to discharge with limited power. 4. The method according to claim 1, characterized in that the method further comprises: When the temperature value of the battery module is lower than the low temperature threshold of the battery module, the power-limited discharge of the battery module is enabled. 5. The method according to claim 1, characterized in that the method further comprises: When the temperature value of the battery module is higher than the high temperature threshold of the battery module, the power-limited discharge of the battery module is enabled. 6. A battery module discharge device for a vehicle-mounted rechargeable energy storage system, characterized in that it comprises: The battery module temperature detection module is used to detect the temperature value of the battery module; The temperature detection module outside the vehicle is used to detect the temperature value of the environment outside the vehicle; The discharging module is used for when the temperature value of the battery module is higher than the preset low temperature threshold of the battery module and lower than the preset high temperature threshold of the battery module, and the ambient temperature outside the vehicle is high When the preset ambient low temperature threshold is lower than the preset ambient high temperature threshold, the battery module is enabled to discharge at full power. 7. The device of claim 6, wherein: The discharge module is further configured to enable power-limited discharge of the battery module when the ambient temperature outside the vehicle is lower than the ambient low temperature threshold. 8. The device of claim 6, wherein: The discharge module is further configured to enable power-limited discharge of the battery module when the ambient temperature outside the vehicle is higher than the ambient high temperature threshold. 9. The apparatus of claim 6, wherein: The discharge module is further configured to enable power-limited discharge of the battery module when the temperature value of the battery module is lower than the low temperature threshold of the battery module. 10. The apparatus of claim 6, wherein: The discharge module is further configured to enable power-limited discharge of the battery module when the temperature value of the battery module is higher than the high temperature threshold of the battery module.