Lithium ion battery pack heating loop control system

Abstract

The utility model belongs to the technical field of battery pack control, and particularly relates to a lithium ion battery pack heating loop control system, which comprises a battery module, a single heating control loop, a charging control loop and a discharging control loop, the charging control loop comprises a charging positive electrode, a charging relay and a charging negative electrode, the single heating control loop comprises a heating relay and a heating film, the A1 end of the heating relay is connected with the A2 end of the charging relay, the A2 end of the heating relay is connected with the heating film, and the other end of the heating film is connected to the SHUNT + end of the shunt. The lithium ion battery pack is reasonable in design, simple in structure and convenient to process, the lithium ion battery pack can have a charging heating function and a discharging heating function through a single heating control loop, the using number of heating relays and other electrical parts is reduced, the number requirement for BMS hardware resources is reduced, and the control strategy is simplified.

Description

Technical Field

[0001] This utility model belongs to the field of battery pack control technology, and in particular relates to a heating circuit control system for a lithium-ion battery pack. Background Technology

[0002] With the introduction of the national "dual carbon" target, energy conservation and environmental protection have become the main theme of manufacturing development, and electrification has become an important development direction for the construction machinery industry. Construction machinery is characterized by high usage frequency, long working hours, high rated power, and harsh operating environments. Therefore, a good battery operating temperature is an important prerequisite for ensuring the safe and efficient operation of vehicles.

[0003] Currently, existing battery pack control systems generally include charging and discharging heating circuits for convenient control during battery pack application. However, these systems have certain drawbacks: at least one additional heating relay is required for control, and the BMS hardware must reserve control and adhesion detection functions for at least two heating relays. Furthermore, if only the charging heating control circuit is retained in the control system, the drawback is that if the low-temperature discharge performance of the battery cells is insufficient, the vehicle cannot quickly enter the optimal discharge state in low-temperature environments and needs to first discharge at low power to slowly raise the temperature, resulting in a longer waiting time for the user. Therefore, a lithium-ion battery pack heating circuit control system is provided. Utility Model Content

[0004] This invention addresses the technical problems existing in the battery pack circuit control process mentioned above by proposing a lithium-ion battery pack heating circuit control system that is reasonably designed, simple in structure, easy to manufacture, and can realize charging heating and discharging heating functions of lithium-ion battery packs through a single heating control circuit. This reduces the number of heating relays and other electrical components used, reduces the number of BMS hardware resources required, and simplifies the control strategy.

[0005] To achieve the above objectives, the present invention adopts a lithium-ion battery pack heating circuit control system, comprising a battery module, a single heating control circuit, a charging control circuit, and a discharging control circuit. The discharging control circuit includes a positive discharge terminal, a discharge relay, a fuse, a shunt, and a negative discharge terminal. The charging control circuit includes a positive charging terminal, a charging relay, and a negative charging terminal. The single heating control circuit includes a heating relay and a heating film. The A1 terminal of the heating relay is connected to the A2 terminal of the charging relay, and the A2 terminal of the heating relay is connected to the heating film. The other end of the heating film is connected to the SHUNT+ terminal of the shunt.

[0006] Preferably, the charging relay and the discharging relay in the charging control circuit and the discharging control circuit are connected in parallel, and the charging relay in the charging control circuit is connected in series with the single heating control circuit.

[0007] Preferably, in the discharge control circuit, the discharge relay A2 terminal is connected to the positive discharge phase, the discharge relay A1 terminal is connected to the fuse, the other end of the fuse is connected to the positive terminal of the battery module, the shunt+ terminal of the shunt is connected to the negative discharge phase, and the shunt- terminal of the shunt is connected to the negative terminal of the battery module.

[0008] Preferably, in the charging control circuit, the charging relay A1 terminal is connected to the positive charging phase, the charging relay A2 terminal is connected between the discharge relay A1 terminal and the fuse, and the charging negative terminal is connected to the shunt+ terminal of the shunt.

[0009] Compared with the prior art, the advantages and positive effects of this utility model are as follows:

[0010] 1. This utility model provides a lithium-ion battery pack heating circuit control system. By utilizing the coordination between a single heating control circuit, a charging control circuit, and a discharging control circuit, it solves the problem that a single heating circuit cannot simultaneously achieve charging heating and discharging heating. In other words, a single heating circuit can achieve both charging heating and discharging heating, addressing the shortage of BMS hardware resources, reducing the number of electrical components, and increasing the energy density of the battery pack. This further conserves BMS hardware resources to a certain extent, eliminating the need for additional electrical components inside the battery pack. The device is rationally designed, simple in structure, and easy to manufacture. It enables a lithium-ion battery pack to have both charging and discharging heating functions through a single heating control circuit, reducing the number of heating relays and other electrical components required, decreasing the quantity requirements for BMS hardware resources, and simplifying the control strategy. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of a heating circuit control system for a lithium-ion battery pack.

[0013] In the above diagrams, 1. Battery module; 2. Discharge positive; 3. Discharge relay; 4. Fuse; 5. Shunt; 6. Discharge negative; 7. Charging positive; 8. Charging relay; 9. Charging negative; 10. Heating relay; 11. Heating film. Detailed Implementation

[0014] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0015] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0016] Examples, such as Figure 1 As shown, a lithium-ion battery pack heating circuit control system includes a battery module 1, a single heating control circuit, a charging control circuit, and a discharging control circuit. The discharging control circuit includes a discharge relay 3, a fuse 4, a shunt 5, a positive discharge relay 2, and a negative discharge relay 6. The connections between these components are as follows: the discharge relay 3A2 terminal is connected to the positive discharge relay 2, the discharge relay 3A1 terminal is connected to the fuse 4, the other end of the fuse 4 is connected to the positive terminal of the battery module 1, the negative discharge relay 6 is connected to the shunt+ terminal of the shunt 5, and the shunt- terminal of the shunt 5 is connected to the negative terminal of the battery module 1. The charging control circuit includes a charging relay 8, a positive charging relay 7, and a negative charging relay 9. The connections between these components are as follows. In the charging control circuit, the charging relay 8A1 terminal is connected to the positive charging 7, the charging relay 8A2 terminal is connected between the discharge relay 3A1 terminal and the fuse 4, and the negative charging 9 terminal is connected to the shunt+ terminal of the shunt 5. For the single heating control circuit, it includes a heating relay 10 and a heating film 11. The connections of each component are as follows: the heating relay 10A1 terminal is connected to the charging relay 8A2 terminal, the heating relay 10A2 terminal is connected to the heating film 11, and the other end of the heating film 11 is connected to the shunt+ terminal of the shunt 5. That is to say, the charging relay 8 and the discharge relay 3 in the charging control circuit and the discharge control circuit are connected in parallel, and the charging relay 8 in the charging control circuit and the single heating control circuit are connected in series.

[0017] The specific usage process is described as follows: When the vehicle is started in a low-temperature environment, the battery temperature is low and cannot achieve optimal discharge performance. The BMS can control the heating relay 10 to close, so that the battery supplies power to the heating film 11 to generate heat, and the heating film 11 generates heat, so that the battery can quickly heat up and ensure that the battery reaches the optimal discharge temperature in a short time.

[0018] When electric vehicles need to be charged in low-temperature conditions, the BMS can control the heating relay 10 and the charging relay 8 to close. At the same time, the BMS sends a request current of the rated current of the heating film 11. At this time, almost all the current output by the charger is consumed by the heating film 11 and will not charge the battery. Even if there is current instability, the battery will only undergo a very small instantaneous charge and discharge, which has no impact on battery life and safety. If there is long-term current instability, the BMS can dynamically adjust the request current according to the current collected by the shunt 5 in the battery pack.

[0019] Furthermore, if the BMS relay control resources are sufficient, a heating negative relay can be added to the negative terminal of the heating circuit to further ensure the safety of the heating circuit and prevent the heating relay 10 from sticking together and causing overheating.

[0020] In the above process, by utilizing the coordination between the established single heating control loop, charging control loop, and discharging control loop, the problem that a single heating loop cannot simultaneously achieve charging heating and discharging heating is solved. That is, a single heating loop can achieve charging heating and discharging heating, solving the problem of insufficient BMS hardware resources, reducing the number of electrical components, and increasing the energy density of the battery pack. This further saves BMS hardware resources to a certain extent, eliminating the need for additional electrical components inside the battery pack. This device is reasonably designed, has a simple structure, is easy to manufacture, and can enable lithium-ion battery packs to have charging heating and discharging heating functions through a single heating control loop. This reduces the number of heating relays 10 and other electrical components used, reduces the number of BMS hardware resources required, and simplifies the control strategy.

[0021] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A lithium-ion battery pack heating circuit control system, comprising a battery module, a single heating control circuit, a charging control circuit, and a discharging control circuit, characterized in that, The discharge control circuit includes a discharge positive terminal, a discharge relay, a fuse, a shunt, and a discharge negative terminal. The charging control circuit includes a charging positive terminal, a charging relay, and a charging negative terminal. The single heating control circuit includes a heating relay and a heating diaphragm. The A1 terminal of the heating relay is connected to the A2 terminal of the charging relay. The A2 terminal of the heating relay is connected to the heating diaphragm. The other end of the heating diaphragm is connected to the SHUNT+ terminal of the shunt.

2. The lithium-ion battery pack heating circuit control system according to claim 1, characterized in that, The charging and discharging relays in the charging and discharging control circuits are connected in parallel, and the charging relay in the charging control circuit is connected in series with the single heating control circuit.

3. A lithium-ion battery pack heating circuit control system according to claim 2, characterized in that, In the discharge control circuit, the discharge relay A2 terminal is connected to the positive discharge phase, the discharge relay A1 terminal is connected to the fuse, the other end of the fuse is connected to the positive terminal of the battery module, the shunt+ terminal of the shunt is connected to the negative discharge phase, and the shunt- terminal of the shunt is connected to the negative terminal of the battery module.

4. A lithium-ion battery pack heating circuit control system according to claim 3, characterized in that, In the charging control circuit, the charging relay A1 terminal is connected to the positive charging phase, the charging relay A2 terminal is connected between the discharge relay A1 terminal and the fuse, and the charging negative terminal is connected to the shunt+ terminal of the shunt.

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