Battery module control methods, battery modules and electric vehicles

Abstract

This invention discloses a battery module control method, a battery module, and an electric vehicle. The battery module control method is applied to an electric vehicle, which includes a battery module. The battery module includes a discharge terminal and N auxiliary battery packs, where N is greater than or equal to 1. The battery module control method includes: first, acquiring the voltage values ​​of the N auxiliary battery packs and the vehicle status information of the electric vehicle; when the vehicle status information determines that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and a preset voltage value is less than a first preset voltage difference, controlling all auxiliary battery packs to connect to the discharge terminal; when the vehicle status information determines that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and a preset voltage value is greater than the first preset voltage difference, controlling the N auxiliary battery packs to connect to the discharge terminal sequentially, one at a time. This invention aims to improve the efficiency of users installing auxiliary battery packs at battery swapping stations.

Description

Technical Field

[0001] This invention relates to the field of battery module technology, and in particular to a battery module control method, a battery module, and an electric vehicle. Background Technology

[0002] The electric vehicle industry is developing rapidly, and its outstanding advantages, such as intelligence and low operating costs, have attracted many consumers. However, electric vehicles suffer from a relatively short driving range. To address this, some vehicle manufacturers are planning to develop electric vehicles that can be equipped with an auxiliary battery pack. This auxiliary battery pack, connected in parallel with the main battery pack already installed in the battery module, expands the battery capacity and increases the driving range of the electric vehicle.

[0003] In practical applications, users typically drive their electric vehicles to battery swapping stations to install auxiliary battery packs. Since the auxiliary battery packs installed in the battery module are all connected in parallel with the main battery pack, the voltage difference between the auxiliary and main battery packs needs to be considered when adjusting the number of connected battery packs at the swapping station to ensure consistency among the multiple battery packs within the module (multiple battery packs with insufficient consistency connected in parallel for charging and discharging will lead to battery life degradation). This necessitates additionally measuring the SOC of the already connected main battery pack and adjusting the SOC of the auxiliary battery packs accordingly to ensure near-identical SOCs. This process is cumbersome and time-consuming, making it inconvenient for users every time they need to install an auxiliary battery pack, thus reducing the convenience of using electric vehicles. Summary of the Invention

[0004] The main objective of this invention is to provide a battery module control method, a battery module, and an electric vehicle to improve the efficiency of users adding auxiliary battery packs at battery swapping stations, thereby improving the convenience of users using electric vehicles.

[0005] To achieve the above objectives, this invention proposes a battery module control method applied to an electric vehicle. The electric vehicle includes a battery module, which includes a discharge terminal and N auxiliary battery packs, where N is greater than or equal to 1. The battery module control method includes:

[0006] Obtain the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle;

[0007] When it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value is less than the first preset voltage difference, control all the auxiliary battery packs to be connected to the discharge terminal.

[0008] When it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value is greater than the first preset voltage difference, the N auxiliary battery packs are controlled to be connected to the discharge terminal one at a time according to the strategy of connecting one at a time.

[0009] Optionally, the battery module further includes a main battery pack. Between the steps of acquiring the voltage values ​​of the N auxiliary battery packs and the vehicle status information of the electric vehicle, and the step of controlling all auxiliary battery packs to connect to the discharge terminal when it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and a preset voltage value is less than a first preset voltage difference, the battery module control method further includes:

[0010] Obtain the number of auxiliary battery packs within the battery module;

[0011] If the number of auxiliary battery packs is equal to one, obtain the voltage value of the main battery pack, and configure the preset voltage value as the voltage value of the main battery pack;

[0012] If the number of auxiliary battery packs is greater than one, the preset voltage value is configured to be the voltage value of any other auxiliary battery pack.

[0013] Optionally, the step of controlling the N auxiliary battery packs to be connected to the discharge terminal one at a time according to the strategy is as follows:

[0014] Sort the N auxiliary battery packs in descending order of voltage value;

[0015] The auxiliary battery pack with the highest control voltage value is connected to the discharge terminal;

[0016] When the voltage difference between the voltage value of the auxiliary battery pack connected to the discharge terminal and the voltage value of the auxiliary battery pack with the second highest voltage value is less than a first preset voltage difference, the auxiliary battery pack with the second highest voltage value is also connected to the discharge terminal, until all the auxiliary battery packs are connected to the discharge terminal.

[0017] Optionally, the battery module further includes a main battery pack, and after the step of controlling all the auxiliary battery packs to be connected to the discharge terminal, the battery module control method further includes:

[0018] When the voltage of the auxiliary battery pack connected to the discharge terminal is lower than the preset high output voltage value and the electric vehicle is determined to be in an acceleration state according to the vehicle status information, the main battery pack is controlled to be connected to the discharge terminal together or the main battery pack is controlled to be connected to the discharge terminal alone.

[0019] When it is determined from the vehicle status information that the electric vehicle has returned to cruise control, the main battery pack is controlled to disconnect from the electrical connection with the discharge terminal.

[0020] Optionally, the battery module control method further includes:

[0021] When it is determined from the vehicle status information that the electric vehicle is in a stationary state and the voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value is less than the preset stationary voltage difference, all the auxiliary battery packs are controlled to be connected to the discharge terminal.

[0022] When it is determined from the vehicle status information that the electric vehicle is in a stationary state and there is a voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value that is greater than the preset stationary voltage difference, the N auxiliary battery packs are controlled to be connected to the discharge terminal one by one in a sequential manner.

[0023] Wherein, the preset static voltage difference is less than the first preset voltage difference.

[0024] Optionally, the battery module further includes a main battery pack and a charging terminal, and the step of obtaining the voltage values ​​of the N auxiliary battery packs and the vehicle status information of the electric vehicle further includes:

[0025] Obtain the voltage value of the main battery pack;

[0026] The battery module control method further includes:

[0027] When the vehicle status information determines that the electric vehicle is in a state of waiting to be charged and the voltage difference between any two battery packs among the main battery pack and the N auxiliary battery packs is less than the second preset voltage difference, the main battery pack and the N auxiliary battery packs are connected in series to the charging terminal, and the user is prompted that series charging can be performed at this time.

[0028] When the vehicle status information determines that the electric vehicle is in a state of waiting to be charged and the voltage difference between two battery packs among the main battery pack and the N auxiliary battery packs is greater than the second preset voltage difference, the main battery pack and the N auxiliary battery packs are controlled to be connected to the charging terminal one by one in turn, and the user is prompted that series charging cannot be performed at this time.

[0029] Optionally, the step of controlling the main battery pack and the N auxiliary battery packs to be connected in parallel to the charging terminal one at a time includes:

[0030] Sort the N auxiliary battery packs and the main battery packs in descending order of voltage value;

[0031] The battery pack with the lowest voltage value among the auxiliary battery pack and the main battery pack is connected to the charging terminal.

[0032] When the voltage difference between the battery pack connected to the charging terminal and the battery pack with the second lowest voltage value is less than a second preset voltage difference, the battery pack with the second lowest voltage value is also connected to the charging terminal, until the main battery pack and all the auxiliary battery packs are connected to the charging terminal in parallel.

[0033] Optionally, the battery module further includes a main battery pack and a charging terminal, the charging terminal being used to connect to the charging pile, and the step of obtaining the voltage values ​​of the N auxiliary battery packs and the vehicle status information of the electric vehicle further includes:

[0034] Obtain the voltage value of the main battery pack and the number of auxiliary battery packs within the battery module;

[0035] The battery module control method further includes:

[0036] When it is determined that the electric vehicle is in a state of waiting to be charged based on the vehicle status information, a communication connection is established with the charging pile.

[0037] When the voltage difference between any two battery packs in the main battery pack and the N auxiliary battery packs is less than the second preset voltage difference, the main battery pack and the N auxiliary battery packs are connected in series to the charging terminal. The corresponding voltage demand signal is output to the charging pile according to the number of auxiliary battery packs and the main battery pack in the battery module, so that the charging pile outputs a charging voltage with a voltage value corresponding to the voltage demand signal to charge all the auxiliary battery packs and the main battery pack connected in series.

[0038] When the voltage difference between any two of the main battery pack and the N auxiliary battery packs is greater than a second preset voltage difference, the main battery pack and the N auxiliary battery packs are connected in series to the charging terminal one at a time according to a strategy. Based on the number of auxiliary battery packs and main battery packs connected in series to the charging terminal, a corresponding voltage demand signal is output to the charging pile so that the charging pile outputs a charging voltage with a voltage value corresponding to the voltage demand signal.

[0039] Optionally, the step of controlling the main battery pack and the N auxiliary battery packs to be connected in series to the charging terminal one at a time according to the strategy of connecting one at a time specifically includes:

[0040] Sort the N auxiliary battery packs and the main battery packs in descending order of voltage value;

[0041] The battery pack with the lowest voltage value among the auxiliary battery pack and the main battery pack is connected to the charging terminal.

[0042] When the voltage difference between the battery pack connected to the charging terminal and the battery pack with the second lowest voltage value is less than a second preset voltage difference, the battery pack with the second lowest voltage value is also connected in series to the charging terminal, until the main battery pack and all the auxiliary battery packs are connected in series to the charging terminal.

[0043] The present invention also proposes a battery module for use in electric vehicles, the battery module comprising:

[0044] N auxiliary battery packs;

[0045] Memory;

[0046] A processor having a communication terminal for communicatively connecting with the electric vehicle;

[0047] Charging end;

[0048] Discharge terminal;

[0049] Switch array;

[0050] A battery module control program stored in the memory and executed by the processor, wherein the battery module control program, when executed by the processor, implements the battery module control method as described above;

[0051] The processor is electrically connected to N auxiliary battery packs, the switch array, and the memory, respectively; the switch array is electrically connected to N auxiliary battery packs, the discharge terminal, and the charging terminal, respectively.

[0052] Optionally, the battery module further includes:

[0053] The main battery pack is electrically connected to the processor and the switch array, respectively.

[0054] Optionally, the processor has a second communication terminal for establishing a communication connection with the charging pile vehicle.

[0055] The present invention also proposes an electric vehicle comprising the battery module described in any of the preceding claims.

[0056] In this invention, the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle are first obtained. When the vehicle status information determines that the electric vehicle is in motion and the voltage difference between any auxiliary battery pack and a preset voltage value is less than a first preset voltage difference, all auxiliary battery packs are controlled to connect to the discharge terminal. Conversely, when the vehicle status information determines that the electric vehicle is in motion and the voltage difference between any auxiliary battery pack and a preset voltage value is greater than the first preset voltage difference, the N auxiliary battery packs are controlled to connect to the discharge terminal one at a time. Thus, when a user needs to add auxiliary battery packs to the battery module of an electric vehicle at a battery swapping station, there is no need to additionally measure the current SOC of the main battery pack or adjust the SOC of the auxiliary battery pack to be added. The user only needs to directly connect the corresponding number of auxiliary battery packs to the battery module according to the mileage requirement, and can then drive away directly. During the journey, the lifespan of each battery pack will not be shortened due to inconsistencies. This effectively shortens the time for users to add auxiliary batteries at battery swapping stations while ensuring the normal operation of the battery packs, thereby improving the convenience of long-distance driving for users of electric vehicles. Meanwhile, since there's no need to adjust the SOC of the connected auxiliary battery pack based on the SOC of the main battery pack, users can directly connect at least one fully charged auxiliary battery pack to the battery module at a battery swapping station to maximize the electric vehicle's range. Furthermore, if the electric vehicle runs out of power during its journey, users can easily connect stored unused auxiliary battery packs to the battery module, or directly remove excess auxiliary battery packs from other vehicles and connect them, ensuring normal vehicle operation and preventing shortened lifespans due to inconsistencies among battery packs, further enhancing user convenience. In addition, since auxiliary battery packs can be replaced at any time, while the main battery pack is integrated into the electric vehicle's battery module and difficult to replace, this invention prioritizes discharging the auxiliary battery pack to minimize the main battery pack's participation in the discharge process, thereby reducing the main battery pack's discharge cycle count and extending its lifespan. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0058] Figure 1 This is a schematic flowchart of an embodiment of the battery module control method of the present invention;

[0059] Figure 2This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0060] Figure 3 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0061] Figure 4 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0062] Figure 5 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0063] Figure 6 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0064] Figure 7 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0065] Figure 8 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0066] Figure 9 This is a schematic flowchart of another embodiment of the battery module control method of the present invention;

[0067] Figure 10 This is a circuit diagram of an embodiment of the battery module of the present invention.

[0068] Explanation of icon numbers:

[0069]

[0070] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0071] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0072] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0073] The electric vehicle industry is developing rapidly, and its outstanding advantages, such as intelligence and low operating costs, have attracted many consumers. However, electric vehicles suffer from a relatively short driving range. To address this, some vehicle manufacturers are planning to develop electric vehicles that can be equipped with an auxiliary battery pack. This auxiliary battery pack, connected in parallel with the main battery pack already installed in the battery module, expands the battery capacity and increases the driving range of the electric vehicle.

[0074] In practical applications, users typically drive their electric vehicles to battery swapping stations to install auxiliary battery packs. Since the auxiliary battery packs installed in the battery module are all connected in parallel with the main battery pack, the voltage difference between the auxiliary and main battery packs needs to be considered when adjusting the number of connected battery packs at the swapping station to ensure consistency among the multiple battery packs within the module (multiple battery packs with insufficient consistency connected in parallel for charging and discharging will lead to battery life degradation). This necessitates additionally measuring the SOC of the already connected main battery pack and adjusting the SOC of the auxiliary battery packs accordingly to ensure near-identical SOCs. This process is cumbersome and time-consuming, making it inconvenient for users every time they need to install an auxiliary battery pack, thus reducing the convenience of using electric vehicles.

[0075] Therefore, this invention proposes a battery module control method, a battery module, and an electric vehicle. The battery module control method is applied to an electric vehicle, which includes a battery module. The battery module includes a discharge terminal and N auxiliary battery packs, where N is greater than or equal to 1.

[0076] refer to Figure 1 In one embodiment of the present invention, the battery module control method includes:

[0077] Step S10: Obtain the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle;

[0078] Step S20: When it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and the preset voltage value is less than the first preset voltage difference, control all auxiliary battery packs to connect to the discharge terminal.

[0079] Step S30: When it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and the preset voltage value is greater than the first preset voltage difference, control the N auxiliary battery packs to be connected to the discharge end one by one according to the strategy of connecting one at a time.

[0080] It is understood that the battery module may be equipped with a processor for executing the battery module control method, and a switch array electrically connected to all auxiliary battery packs, main battery packs, discharge terminals, charging terminals and the processor. Under the control of the processor, the switch array can control different battery packs to be in parallel / series state, and can also conduct the path between different battery packs and discharge / charging terminals, so as to realize that the battery packs can be connected to the charging terminal or discharge terminal individually / in parallel / in series to perform corresponding charging and discharging actions.

[0081] The battery module can be equipped with multiple interfaces for connecting at least one auxiliary battery pack. Optionally, in one embodiment, the interfaces are also electrically connected to a processor, so that each auxiliary battery pack installed in the battery module can establish an electrical connection with the processor. The processor can directly establish a communication connection with the BMS module within the connected auxiliary battery pack, thereby directly obtaining the battery voltage information sent by the BMS module of the auxiliary battery pack to determine the current voltage value of the auxiliary battery pack. Optionally, in another embodiment, the battery module can also be equipped with multiple voltage detection circuits, such as resistor voltage divider circuits, voltage detection chips, etc. The detection terminals of the voltage detection circuits are connected to multiple interfaces to detect the voltage value of the currently connected auxiliary battery pack and output corresponding voltage detection signals to the processor, so that the processor can confirm the voltage value of each connected auxiliary battery pack. It is understood that the processor in the battery module should have a communication terminal electrically connected to the vehicle controller of the electric vehicle, so as to realize mutual communication with the vehicle controller of the electric vehicle to access the vehicle status information output by the vehicle controller, such as driving status, stationary mode, cruise control status, acceleration status, waiting to charge status, charging status, etc.

[0082] In this embodiment, when the processor confirms that the electric vehicle is in a driving state, it compares the voltage value of each auxiliary battery pack with the preset voltage value and calculates the voltage difference. If the voltage difference between the voltage value of any auxiliary battery pack and the preset voltage value is less than the first preset voltage difference, the processor will consider that the consistency of all the auxiliary battery packs is good and will control the switch array to operate so that all the auxiliary battery packs are connected in parallel and connected to the discharge terminal so that all the auxiliary battery packs are discharged in parallel together.

[0083] If the voltage difference between any auxiliary battery pack and the preset voltage value is greater than the first preset voltage difference, the processor will consider that the consistency of the current N auxiliary battery packs is insufficient, and will then control the N auxiliary battery packs to be connected to the discharge end one by one according to the strategy of connecting one at a time.

[0084] Optionally, in one embodiment, when the processor confirms insufficient consistency among the N auxiliary battery packs, the auxiliary battery packs can be numbered in any order. The processor first controls the switch array to individually connect the path between auxiliary battery pack #1 and the discharge terminal, while simultaneously monitoring the voltage of auxiliary battery pack #1. When the voltage of auxiliary battery pack #1 falls below the low-charge voltage, it is considered that auxiliary battery pack #1 is approaching a low-charge state. The processor then controls the switch array to disconnect the path between auxiliary battery pack #1 and the discharge terminal, and individually connects the path between auxiliary battery pack #2 and the discharge terminal, allowing auxiliary battery pack #2 to begin discharging. This process continues until all auxiliary battery packs are in a low-charge state. Only then is the switch array controlled to connect the path between the main battery pack and the discharge terminal, allowing the main battery pack to begin discharging. Thus, when the user adds auxiliary battery packs, there is no need to consider the consistency differences between the auxiliary battery packs or between the auxiliary and main battery packs. When the consistency of the auxiliary battery packs is poor, the processor controls each auxiliary battery pack to discharge individually, preventing consistency differences from affecting the lifespan of the auxiliary battery pack itself or other auxiliary battery packs or the main battery pack.

[0085] It is important to understand that, generally speaking, when driving an electric vehicle, users will sometimes press the accelerator (electric switch) for a relatively long time to increase the output power required by the electric vehicle in a short period of time, thereby controlling the vehicle's acceleration or hill climbing. Therefore, to ensure that users consistently have a good acceleration experience while driving an electric vehicle, alternatively, in another embodiment, refer to... Figure 3 The specific steps for controlling N auxiliary battery packs to be connected to the discharge terminal one at a time are as follows:

[0086] Step S31: Sort the N auxiliary battery packs in descending order of voltage value;

[0087] Step S32: Connect the auxiliary battery pack with the highest control voltage to the discharge terminal;

[0088] Step S33: When the voltage difference between the voltage value of the auxiliary battery pack connected to the discharge terminal and the voltage value of the auxiliary battery pack with the second highest voltage value is less than the first preset voltage difference, control the auxiliary battery pack with the second highest voltage value to also be connected to the discharge terminal, until all auxiliary battery packs are connected to the discharge terminal.

[0089] In this embodiment, when the processor determines that there are inconsistencies in the consistency of the current auxiliary battery packs (insufficient consistency), it first sorts the auxiliary battery packs according to their voltage values ​​from high to low, and then controls the switch array to connect the auxiliary battery pack with the highest voltage to the discharge terminal. During vehicle operation, the voltage of the auxiliary battery packs gradually decreases. When the processor determines that the voltage difference between the auxiliary battery pack currently connected to the discharge terminal and the original second-highest voltage auxiliary battery pack is less than a first preset voltage difference, it considers the consistency between the auxiliary battery pack already connected to the discharge terminal and the original second-highest voltage auxiliary battery pack to be good. It then controls the switch array to connect the original second-highest voltage auxiliary battery pack to the discharge terminal, allowing the two auxiliary battery packs to discharge in parallel through the discharge terminal. Similarly, this process continues until the processor controls the switch array to connect all auxiliary battery packs in parallel to the discharge terminal. Likewise, only when all auxiliary battery packs are connected in parallel to the discharge terminal and their voltage drops to a low level will the processor control the switch array to disconnect the paths between multiple auxiliary battery packs and the discharge terminal, and then connect the path between the main battery pack and the discharge terminal individually. Therefore, when users add auxiliary battery packs, there is no need to consider the consistency differences between the auxiliary battery packs or between the auxiliary battery pack and the main battery pack. During the electric vehicle's operation, if the consistency of the N auxiliary battery packs is insufficient, the processor will adjust the voltage of the N auxiliary battery packs according to the above scheme, and connect the m (m≤N) auxiliary battery packs with better consistency in parallel to discharge together through the discharge terminal, until all auxiliary battery packs are connected in parallel and discharged together through the discharge terminal. This shortens the time for users to add auxiliary batteries at the battery swapping station, improves the convenience of using the electric vehicle, and also ensures good acceleration performance of the electric vehicle, improving the comfort and convenience of driving the electric vehicle. In addition, in the above embodiments, the auxiliary battery packs are discharged first to ensure that the main battery pack is not discharged as much as possible, thereby reducing the discharge cycle number of the main battery pack and improving its service life.

[0090] It is understood that the preset voltage value in the above embodiments can be determined based on the number of auxiliary battery packs connected. Specifically, refer to... Figure 2 The battery module also includes a main battery pack. Between step S10 and step S20, the battery module control method further includes:

[0091] Step S40: Obtain the number of auxiliary battery packs within the battery module;

[0092] Optionally, in one embodiment, the battery module can determine whether an auxiliary battery pack is currently connected based on the voltage signals output by the multiple voltage detection circuits that are connected one-to-one with the multiple interfaces in the above embodiment. If no auxiliary battery pack is connected, the voltage detection circuit will directly output a voltage detection signal of 0V. If an auxiliary battery pack is currently connected, the voltage detection circuit will output a voltage detection signal of the corresponding voltage. When the processor detects that the current voltage detection signal is not 0V, it can determine that the corresponding interface is connected to an auxiliary battery pack. Then the processor can know how many interfaces are currently connected to auxiliary battery packs, that is, determine the number of auxiliary battery packs installed and connected to the battery module, i.e., the specific value of N. In this way, even if the auxiliary battery pack does not support communication with the processor, the method of the above embodiment can still be adapted.

[0093] Optionally, in another embodiment, the processor can communicate directly with the auxiliary battery packs accessed through the interface to determine the number of currently accessed auxiliary battery packs, i.e., the specific value of N.

[0094] Step S50: If the number of auxiliary battery packs is equal to one, obtain the voltage value of the main battery pack and configure the preset voltage value as the voltage value of the main battery pack.

[0095] Step S60: If the number of auxiliary battery packs is greater than one, then the preset voltage value is configured to the voltage value of any other auxiliary battery pack.

[0096] When the number of currently connected auxiliary battery packs is determined to be one, the voltage value of the main battery pack is obtained according to the same scheme as in the above embodiment, and the voltage value of the main battery pack is configured to a preset voltage value. At this time, according to the scheme of the above embodiment, when the vehicle is in motion, the processor will control the auxiliary battery to discharge separately, and when the auxiliary battery pack is discharged to a low level, the main battery pack will be connected to discharge.

[0097] When it is determined that the number of currently connected auxiliary battery packs is greater than one, the preset voltage value is configured as the voltage value of any other auxiliary battery pack. In other words, in the above embodiment, the voltage value of any auxiliary battery pack is compared with the voltage values ​​of all other auxiliary battery packs. If the voltage differences obtained after comparing the voltage values ​​of any auxiliary battery pack with the voltage values ​​of all other auxiliary battery packs are all less than the first preset voltage difference, that is, the voltage difference between any two auxiliary battery packs is less than the first preset voltage difference, it indicates that the consistency among the current auxiliary battery packs is good. If the voltage difference between one auxiliary battery pack and at least one other auxiliary battery pack is greater than the first preset voltage difference, it indicates that the consistency among the current auxiliary battery packs is insufficient. The first preset voltage difference is obtained by the developers through multiple experiments and is pre-stored in the processor.

[0098] In this invention, the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle are first obtained. When the vehicle status information determines that the electric vehicle is in motion and the voltage difference between any auxiliary battery pack and a preset voltage value is less than a first preset voltage difference, all auxiliary battery packs are controlled to connect to the discharge terminal. Conversely, when the vehicle status information determines that the electric vehicle is in motion and the voltage difference between any auxiliary battery pack and a preset voltage value is greater than the first preset voltage difference, the N auxiliary battery packs are controlled to connect to the discharge terminal one at a time. Thus, when a user needs to add auxiliary battery packs to the battery module of an electric vehicle at a battery swapping station, there is no need to additionally measure the current SOC of the main battery pack or adjust the SOC of the auxiliary battery pack to be added. The user only needs to directly connect the corresponding number of auxiliary battery packs to the battery module according to the mileage requirement, and can then drive away directly. During the journey, the lifespan of each battery pack will not be shortened due to inconsistencies. This effectively shortens the time for users to add auxiliary batteries at battery swapping stations while ensuring the normal operation of the battery packs, thereby improving the convenience of long-distance driving for users of electric vehicles. Meanwhile, since there's no need to adjust the SOC of the connected auxiliary battery pack based on the SOC of the main battery pack, users can directly connect at least one fully charged auxiliary battery pack to the battery module at a battery swapping station to maximize the electric vehicle's range. Furthermore, if the electric vehicle runs out of power during its journey, users can easily connect stored unused auxiliary battery packs to the battery module, or directly remove excess auxiliary battery packs from other vehicles and connect them to the battery module. This ensures normal vehicle operation and prevents shortened lifespans due to inconsistencies between battery packs, further enhancing user convenience. In addition, while auxiliary battery packs can be replaced at any time, the main battery pack is pre-installed in the battery module at the factory and is difficult to replace. Therefore, this invention prioritizes discharging the auxiliary battery pack to minimize the main battery pack's participation in the discharge process, thereby reducing the main battery pack's discharge cycle count and extending its actual lifespan.

[0099] It is important to understand that after an electric vehicle has traveled a considerable distance, although all the auxiliary battery packs are now connected to the discharge end, their voltage may have dropped significantly. This can result in the electric vehicle not providing adequate acceleration when the user presses the accelerator pedal.

[0100] Therefore, refer to Figure 4 In one embodiment of the present invention, the battery module further includes a main battery pack. After the step of controlling all auxiliary battery packs to be connected to the discharge terminal, the battery module control method further includes:

[0101] Step S70: When the voltage value of the auxiliary battery pack connected to the discharge terminal is lower than the preset high output voltage value and the electric vehicle is determined to be in an acceleration state according to the vehicle status information, control the main battery pack to be connected to the discharge terminal together or control the main battery pack to be connected to the discharge terminal separately.

[0102] Step S80: When it is determined from the vehicle status information that the electric vehicle has returned to the cruise control state, the main battery pack is controlled to disconnect the electrical connection with the discharge terminal.

[0103] As can be seen from the above embodiments, in order to ensure that the electric vehicle has good acceleration performance during long-term driving, the processor controls the operation of the switch array to eventually adjust multiple auxiliary battery packs with poor consistency to a state with better consistency, and connects all auxiliary battery packs in parallel to the discharge terminal.

[0104] In this embodiment, the processor receives vehicle status information from the vehicle controller via its communication terminal. If the user presses the accelerator (electric switch) to increase the instantaneous output power of the electric vehicle for acceleration, the vehicle controller calculates the instantaneous output power required by the electric vehicle based on the control signal output by the accelerator (electric switch) and transmits it to the processor, informing the processor that the vehicle is currently accelerating. The processor determines the battery SOC required for the current instantaneous output power based on a pre-set output power-SOC mapping table, and then determines the preset voltage value required. If the voltage of the auxiliary battery pack currently connected to the discharge terminal is lower than the preset high output voltage, the processor will control the switch array to temporarily (e.g., only during acceleration) connect the main battery pack with a higher voltage to the discharge terminal to discharge together with the auxiliary battery pack. It is understood that since the auxiliary battery pack is used first, the voltage of the main battery pack is generally higher than that of the auxiliary battery pack after driving for a long time. At this time, the processor can also directly control the switch array to disconnect all auxiliary battery packs from the discharge terminal, so as to control the main battery pack to be connected to the discharge terminal alone for discharge, in order to meet the instantaneous high power output requirements of the electric vehicle and ensure the user's driving experience.

[0105] Understandably, if the vehicle returns to cruise control, the processor will also determine this based on the vehicle status signal received from the vehicle controller. At this point, it will control the switch array to disconnect the path between the main battery pack and the discharge terminal, and recharge all auxiliary battery packs in parallel to the discharge terminal. This minimizes the number of charge-discharge cycles for the main battery pack, thereby extending its actual lifespan.

[0106] It is important to understand that, due to the internal resistance of the battery, there will be a difference between the battery voltage detected during charging and discharging and the battery voltage in a static state.

[0107] Therefore, refer to Figure 5 In one embodiment of the present invention, the battery module control method further includes:

[0108] Step S90: When it is determined from the vehicle status information that the electric vehicle is in a stationary state and the voltage difference between the voltage value of any auxiliary battery pack and the preset voltage value is less than the preset stationary voltage difference, control all auxiliary battery packs to connect to the discharge terminal.

[0109] Step S100: When it is determined from the vehicle status information that the electric vehicle is in a stationary state and the voltage difference between the voltage value of any auxiliary battery pack and the preset voltage value is greater than the preset stationary voltage difference, control the N auxiliary battery packs to be connected to the discharge end one by one according to the strategy of connecting one at a time.

[0110] The preset static voltage difference is less than the first preset voltage difference.

[0111] In this embodiment, when the processor determines that the electric vehicle is in a stationary state based on the vehicle status information transmitted from the vehicle controller, i.e., when the current battery module does not need to output through the discharge terminal or input through the charging terminal, the processor will then detect the voltage value of the current auxiliary battery pack and determine the current preset voltage value in the same way as in the above embodiment. Similar to the voltage difference determination process in the above embodiment, if the voltage difference between any of the current auxiliary battery packs and the preset voltage value is less than the preset stationary voltage difference, it is considered that the consistency of all the auxiliary battery packs currently installed and connected to the battery pack is good, and all auxiliary battery packs can be connected in parallel to the discharge terminal before the electric vehicle starts. If the voltage difference between the current auxiliary battery pack and the preset voltage value is greater than the preset stationary voltage difference, it is considered that the consistency of the current auxiliary battery packs in the static state is poor. In this case, the processor will control N auxiliary battery packs to be connected to the discharge terminal one at a time, following the same process as in the above embodiment, connecting the auxiliary battery pack with the highest voltage first so that the auxiliary battery pack with the highest voltage will discharge first when the vehicle starts running.

[0112] The preset static voltage difference was obtained by the developers through multiple tests during the R&D phase and is pre-stored in the processor. It's important to understand that when the auxiliary battery packs are in a static state, due to differences in manufacturing processes and materials, there will still be voltage differences between the auxiliary battery packs when fully charged at the factory. During actual operation, the voltage difference between the auxiliary battery packs will be further amplified due to internal resistance. Therefore, in this embodiment, the preset static voltage difference should be less than the first preset voltage difference to prevent damage to the batteries caused by the inconsistent parallel discharge of all auxiliary battery packs pre-connected in parallel at the discharge end during static operation when the electric vehicle transitions from a static to an operating state.

[0113] The above settings allow for a reassessment of the consistency of all auxiliary battery packs within the electric vehicle when it returns to a resting state from charging / discharging or when the auxiliary battery pack has just been added to the battery module. This prepares the vehicle for a return to a starting state in advance, shortening the starting time and ensuring good starting performance. Furthermore, it prevents situations where, due to the auxiliary battery packs being in a parallel connection during the previous driving, poor consistency among the auxiliary battery packs might occur during the next start-up, while still discharging in parallel, effectively guaranteeing the actual lifespan of the auxiliary battery packs.

[0114] refer to Figure 6 In one embodiment of the present invention, the battery module further includes a main battery pack and a charging terminal, and step S10 further includes:

[0115] Step S11: Obtain the voltage value of the main battery pack;

[0116] The battery module control method also includes:

[0117] Step S110: When it is determined from the vehicle status information that the electric vehicle is in a state of waiting to be charged and the voltage difference between any two battery packs among the main battery pack and N auxiliary battery packs is less than the second preset voltage difference, control the main battery pack and N auxiliary battery packs to be connected in series to the charging terminal, and prompt the user that series charging can be performed at this time.

[0118] Step S120: When it is determined from the vehicle status information that the electric vehicle is in a state of waiting to be charged and the voltage difference between two battery packs among the main battery pack and N auxiliary battery packs is greater than the second preset voltage difference, control the main battery pack and N auxiliary battery packs to be connected to the charging terminal one by one in turn, and prompt the user that series charging cannot be performed at present.

[0119] In this embodiment, the voltage value of the main battery pack can be obtained in accordance with the method described in the above embodiment. Current charging piles often allow users to select different output voltages, such as 400V or 800V. When the user connects the charging gun to the charging port of the electric vehicle but has not yet started charging, the vehicle controller of the electric vehicle will determine that the electric vehicle is in a waiting-to-charge state and will output corresponding vehicle status information to confirm that the electric vehicle is in a waiting-to-charge state. At this time, if the voltage difference between any two battery packs (which can be two auxiliary battery packs or one main battery pack and one auxiliary battery pack) among the current main battery pack and N auxiliary battery packs is less than the second preset voltage difference, it indicates that the consistency between the current main battery pack and the N auxiliary battery packs is good. The processor will then control the main battery pack and the N auxiliary battery packs to be connected in series to the charging terminal and prompt the user that series charging can now be performed. For example, if the current battery module includes a main battery pack with a standard voltage of 400V and an auxiliary battery pack with a standard voltage of 400V, and the second preset voltage difference is 5V, with the main battery pack currently at 300V and the auxiliary battery pack at 303V, then the main and auxiliary battery packs have good voltage consistency. The processor will control the switch array to connect the main battery pack, auxiliary battery pack, and charging terminal in series, and will prompt the user that 800V series charging is available. The user then only needs to select 800V charging on the charging station, allowing the charging station to output 800V through the charging gun for high-voltage charging of the main and auxiliary battery packs, thereby effectively increasing the charging speed.

[0120] Understandably, there may be multiple auxiliary battery packs, and the maximum output voltage of the charging pile may not be sufficient to charge all auxiliary and main battery packs simultaneously. In this case, after prompting the user to connect them in series, the user can use an interactive device on the electric vehicle, such as a touchscreen, or an external terminal connected to the vehicle, to adjust the connection method of the multiple battery packs to the charging terminal based on the voltage of the current auxiliary and main battery packs displayed on the device, in order to adapt to the charging voltage that the current charging pile can output. For example, if the current charging pile can only output charging voltages of 400V and 800V, and the battery module has 3 auxiliary battery packs and a main battery pack (all with a standard voltage of 400V), then the user can operate the aforementioned interactive device or external terminal to have the processor control the switch array to adjust the 4 auxiliary battery packs into 4 battery packs connected in parallel, and manually control the charging pile to output 400V voltage so that the 4 battery packs are charged in parallel at 400V. Alternatively, the processor can control the switch array to connect two auxiliary battery packs in series, then connect one auxiliary battery pack in series with the main battery pack, and finally connect these two battery packs in parallel to the charging terminal. The user can then manually control the charging pile to output 800V so that the four battery packs can be charged in parallel at 800V.

[0121] If the voltage difference between any two battery packs (which can be two auxiliary battery packs or one main battery pack and one auxiliary battery pack) is greater than the second preset voltage difference, it indicates that the consistency between the current main battery pack and the N auxiliary battery packs is poor. In this case, the processor will control the main battery pack and the N auxiliary battery packs to be connected to the charging terminal one at a time, and will prompt the user that series charging is not currently possible; charging can only be performed according to the basic battery pack standard voltage, such as 400V.

[0122] Optionally, the processor can employ the same control strategy as in the above discharge embodiment. When the user is prompted that the vehicle's consistency is insufficient for series charging, the processor will randomly or sequentially control the switch array according to the numbers of the auxiliary battery packs connected to the main battery pack. This allows one auxiliary battery pack to be connected to the charging terminal individually, enabling the charging pile to output a charging voltage of the appropriate standard value to charge it. Once the processor determines that the individually connected auxiliary battery pack is fully charged, it will control the switch array to disconnect the path between the auxiliary battery pack and the charging terminal, and connect another auxiliary battery pack to the charging terminal so that the charging pile can charge the other auxiliary battery pack. It is understood that this is done to minimize the number of charge / discharge cycles of the main battery pack and extend its actual lifespan.

[0123] Optional, see reference Figure 7 In another embodiment, the step of controlling the main battery pack and N auxiliary battery packs to be connected in parallel to the charging terminal one at a time includes:

[0124] Step S121: Sort the N auxiliary battery packs and the main battery packs in descending order of voltage value;

[0125] Step S122: Connect the battery pack with the lowest voltage value in the auxiliary battery pack and the main battery pack to the charging terminal;

[0126] Step S123: When the voltage difference between the battery pack connected to the charging terminal and the battery pack with the second lowest voltage value is less than the second preset voltage difference, control the battery pack with the second lowest voltage value to also be connected to the charging terminal, until the main battery pack and all auxiliary battery packs are connected to the charging terminal in parallel.

[0127] In this embodiment, the processor first sorts all the current battery packs (including auxiliary battery packs and main battery packs) according to their voltage from high to low, and controls the switch array to connect the battery pack with the lowest voltage to the charging terminal first. If the user controls the charging pile to start outputting charging voltage, the voltage of the connected battery pack will gradually increase. When the voltage difference between the connected battery pack and the original second lowest voltage battery pack is less than a second preset voltage difference, the processor controls the switch array to connect the original second lowest voltage battery pack and the original lowest voltage battery pack in parallel to the charging terminal, so that the charging pile charges the parallel battery packs simultaneously. This process continues until all battery packs are connected in parallel to the charging terminal, thereby ensuring good consistency of the battery packs before parallel charging, thus extending the actual service life of the main battery pack and N auxiliary battery packs.

[0128] Understandably, in another embodiment, the above steps can also involve first sorting the N auxiliary battery packs from highest to lowest voltage, and then connecting only the auxiliary battery pack with the lowest voltage to the charging terminal. The N auxiliary battery packs are then connected in parallel to the charging terminal using the same strategy. Once all auxiliary battery packs are fully charged, if the electric vehicle is still charging, the processor will then connect the main battery pack to the charging terminal separately to prioritize charging the N auxiliary battery packs. This reduces the number of times the main battery pack is charged by default within the battery module, thereby extending the actual lifespan of the main battery pack.

[0129] In the above / below embodiments, the second preset voltage difference can be directly the preset static voltage difference in the above embodiments, or it can be obtained by the R&D personnel through multiple experiments during the R&D period and pre-stored in the battery module.

[0130] It is important to understand that some charging stations can communicate with the battery module of an electric vehicle through the charging gun, and output the corresponding charging voltage according to the charging needs of the battery module.

[0131] Therefore, refer to Figure 8 In one embodiment of the present invention, the battery module further includes a main battery pack and a charging terminal, the charging terminal being used to connect to a charging pile, and step S10 further includes:

[0132] Step S12: Obtain the voltage value of the main battery pack and the number of auxiliary battery packs in the battery module;

[0133] The battery module control method also includes:

[0134] Step S130: When it is determined that the electric vehicle is in a state of waiting to be charged based on the vehicle status information, a communication connection is established with the charging pile.

[0135] Step S140: When the voltage difference between any two battery packs in the main battery pack and N auxiliary battery packs is less than the second preset voltage difference, control the main battery pack and N auxiliary battery packs to be connected in series to the charging terminal, and output the corresponding voltage demand signal to the charging pile according to the number of auxiliary battery packs and main battery packs in the battery module, so that the charging pile outputs a charging voltage with the corresponding voltage value of the voltage demand signal to charge all the auxiliary battery packs and main battery packs connected in series.

[0136] Step S150: When the voltage difference between two battery packs in the main battery pack and N auxiliary battery packs is greater than the second preset voltage difference, control the main battery pack and N auxiliary battery packs to be connected in series to the charging terminal one at a time according to the strategy of connecting one at a time, and output the corresponding voltage demand signal to the charging pile according to the number of auxiliary battery packs and main battery packs connected in series to the charging terminal, so that the charging pile outputs a charging voltage with the voltage value corresponding to the voltage demand signal.

[0137] In this embodiment, the current main battery pack voltage and the number of auxiliary battery packs within the battery module are determined using the same method as in the embodiments described above. The processor also has a second communication terminal for establishing a communication connection with the charging pile. This second communication terminal is connected to a corresponding communication pin on the electric vehicle, enabling the processor to establish a communication connection with the charging pile via the second communication terminal and the charging gun when the charging gun is connected.

[0138] In this embodiment, when the voltage difference between any two battery packs in the main battery pack and the N auxiliary battery packs is less than the second preset voltage difference, it is determined that the current main battery pack and the N auxiliary battery packs are of good consistency. The processor will control the switch array to connect the N auxiliary battery packs, the main battery pack, and the charging terminal in series. Based on the sum of the number of battery packs in the current N auxiliary battery packs and the main battery pack, a corresponding voltage demand signal is output to the charging pile, so that the charging pile outputs a charging voltage corresponding to the voltage demand signal to charge all the series-connected auxiliary battery packs and the main battery pack. For example, if the current battery module has a main battery pack and 3 auxiliary battery packs, each with a standard voltage of 400V, and they are connected in series, the total number of battery packs is 4. Then, the processor will output a corresponding charging demand signal to the charging pile, so that the charging pile outputs a 1200V charging voltage through the charging gun to achieve high-voltage series charging of all battery packs, thereby improving the charging speed.

[0139] When the voltage difference between any two of the main battery pack and the N auxiliary battery packs exceeds a second preset voltage difference, indicating poor consistency between the main battery pack and the N auxiliary battery packs, the processor will control the main battery pack and the N auxiliary battery packs to be connected in series to the charging terminal one at a time, following a strategy of connecting one at a time.

[0140] Specifically, refer to Figure 9The specific steps for controlling the main battery pack and N auxiliary battery packs to be connected in series to the charging terminal one at a time are as follows:

[0141] Step S161: Sort the N auxiliary battery packs and the main battery packs in descending order of voltage value;

[0142] Step S162: Connect the battery pack with the lowest voltage value in the auxiliary battery pack and the main battery pack to the charging terminal;

[0143] Step S163: When the voltage difference between the battery pack connected to the charging terminal and the battery pack with the second lowest voltage value is less than the second preset voltage difference, control the battery pack with the second lowest voltage value to also be connected in series to the charging terminal, until the main battery pack and all auxiliary battery packs are connected in series to the charging terminal.

[0144] In this embodiment, the processor sorts the main battery pack and the N auxiliary battery packs according to their voltage values ​​from highest to lowest based on the obtained voltages of the N auxiliary battery packs and the main battery pack. Then, it controls the switch array to connect the battery pack with the lowest voltage to the charging terminal first. When the user activates the charging pile to begin charging, the processor outputs a corresponding voltage demand signal, ensuring that the charging pile outputs a voltage sufficient to charge one battery pack. For example, if the standard voltage of the auxiliary and main battery packs is 400V, the processor will connect the battery pack with the lowest voltage to the charging terminal when controlling the switch array. The processor outputs a voltage demand signal via the second communication terminal, causing the charging pile to initially output 400V to charge one battery pack. Once the voltage difference between the battery pack connected to the charging terminal and the original second-lowest battery pack is less than a second preset voltage difference, the processor controls the switch array to activate again, connecting the original second-lowest battery pack in series to the charging terminal. At this point, the original lowest battery pack, the original second-lowest battery pack, and the charging terminal are connected in series. The processor then outputs a corresponding voltage demand signal via the second communication terminal, causing the charging pile to output 800V to charge the two series-connected battery packs. This process continues until the main battery pack and N auxiliary battery packs are connected in series to the charging terminal, and the processor outputs a corresponding voltage demand signal to cause the charging pile to output (N+1)*400V to simultaneously charge the main battery pack and the N auxiliary battery packs in series. In practical applications, this allows even battery packs with inconsistent voltage levels to be charged in series, thus accelerating the charging speed.

[0145] It is understood that in the above embodiments, the processor may also disregard the main battery pack and only consider the auxiliary battery packs, performing the charging process described above on the N auxiliary battery packs. After the N auxiliary battery packs have finished charging, if the user still needs to continue charging, the processor controls the switch array to activate the path between the main battery pack and the charging terminal separately, and outputs a corresponding voltage demand signal so that the charging pile outputs a charging voltage suitable for charging a single main battery pack. Thus, in the actual charging process, this invention prioritizes charging the N auxiliary battery packs, thereby reducing the number of times the main battery pack is charged (by default) within the battery module, and extending the actual lifespan of the main battery pack.

[0146] refer to Figure 10 The present invention also proposes a battery module, the battery module comprising:

[0147] At least one auxiliary battery pack;

[0148] Memory 10;

[0149] Processor 20, processor 20 having a communication terminal for communicating with the electric vehicle;

[0150] Charging end;

[0151] Discharge terminal;

[0152] Switch array 30;

[0153] The battery module control program is stored in the memory 10 and executed by the processor 20. When the battery module control program is executed by the processor 20, it implements the battery module control method as described above.

[0154] The processor 20 is electrically connected to at least one auxiliary battery pack, a switch array 30, and a memory 10, respectively; the switch array 30 is electrically connected to at least one auxiliary battery pack, a discharge terminal, and a charging terminal, respectively.

[0155] In this embodiment, the processor 20 may be an MCU, DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), etc. The processor 20 may integrate processing modules such as an ADC detection module, a clock module, and an arithmetic module.

[0156] In this embodiment, the battery module further includes a main battery pack, which is electrically connected to the processor 20 and the switch array 30 respectively. The processor 20 has a second communication terminal for establishing a communication connection with the charging pile.

[0157] In this embodiment, the switch array 30 is composed of multiple switching devices such as relays, MOSFETs, IGBTs, etc. Under the control of the processor 20, the switch array 30 can control the main battery pack or N auxiliary battery packs to form a parallel / series relationship with each other, and control the main battery pack or N auxiliary battery packs to form a parallel / series electrical connection with the charging / discharging terminal.

[0158] It is worth noting that, since the battery module of the present invention includes all embodiments of the above-described battery module control method, the battery module of the present invention has all the beneficial effects of the above-described battery module control method, which will not be repeated here.

[0159] Specifically, refer to Figure 10 The following explanation will be based on an example with one auxiliary battery pack and a switch array 30 including switches A to G.

[0160] As can be seen from the above embodiments, when the processor 20 receives vehicle status information from the vehicle controller via the communication terminal and determines that the vehicle is currently in a driving state, it compares the voltage between the main battery pack and the auxiliary battery pack. If the voltage difference between the main battery pack and the auxiliary battery pack is within the first preset voltage difference, it controls control switches A, B, D, and E to be in the closed state and control switches F, G, and C to be in the open state, so that the main battery pack and the auxiliary battery pack are connected in parallel to the discharge terminal for parallel discharge. If the voltage difference between the main battery pack and the auxiliary battery pack is greater than the first preset voltage difference, it controls control switches D and A to be in the closed state and control switches F, C, B, E, and G to be in the open state, so that the auxiliary battery pack is discharged preferentially.

[0161] When the processor 20 receives vehicle status information from the vehicle controller via the communication terminal and determines that the vehicle is currently in a charging state, it will compare the voltage between the main battery pack and the auxiliary battery pack. If the voltage difference between the main battery pack and the auxiliary battery pack is within the second preset voltage difference, it will control switches C, A, and G to be closed and control switches D, E, B, and F to be open, so that the main battery pack and the auxiliary battery pack are connected in series to the charging terminal, and prompt the user that 800V can be used for charging.

[0162] The present invention also proposes an electric vehicle, which includes a battery module as described in any of the preceding claims.

[0163] It is worth noting that since the electric vehicle of the present invention includes all embodiments of the above-described battery module, the electric vehicle of the present invention has all the beneficial effects of the above-described battery module, which will not be repeated here.

[0164] In this embodiment, the communication terminal of the vehicle controller and the processor within the battery module is connected to enable data and command interaction between the vehicle controller and the battery module, such as receiving acceleration commands from the vehicle controller. The processor of the battery module can feed back various battery parameters output by the BMS in the current multiple battery packs and the switching conduction status of the switch array within the current battery module to the vehicle controller.

[0165] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A battery module control method applied to an electric vehicle, the electric vehicle including a battery module, the battery module including a discharge terminal, N auxiliary battery packs, a charging terminal for connecting to a charging pile, and a main battery pack, wherein N is greater than or equal to 1, characterized in that, The battery module control method includes: Obtain the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle; When it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value is less than the first preset voltage difference, control all the auxiliary battery packs to be connected to the discharge terminal. When it is determined from the vehicle status information that the electric vehicle is in a driving state and there is a voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value that is greater than the first preset voltage difference, the N auxiliary battery packs are controlled to be connected to the discharge terminal one by one in a sequential manner. The battery module control method further includes: When it is determined that the electric vehicle is in a state of waiting to be charged based on the vehicle status information, a communication connection is established with the charging pile. When the voltage difference between any two battery packs in the main battery pack and the N auxiliary battery packs is less than the second preset voltage difference, the main battery pack and the N auxiliary battery packs are connected in series to the charging terminal. The corresponding voltage demand signal is output to the charging pile according to the number of auxiliary battery packs and the main battery pack in the battery module, so that the charging pile outputs a charging voltage with a voltage value corresponding to the voltage demand signal to charge all the auxiliary battery packs and the main battery pack connected in series. When the voltage difference between any two of the main battery pack and the N auxiliary battery packs is greater than a second preset voltage difference, the main battery pack and the N auxiliary battery packs are connected in series to the charging terminal one at a time according to a strategy. Based on the number of auxiliary battery packs and main battery packs connected in series to the charging terminal, a corresponding voltage demand signal is output to the charging pile so that the charging pile outputs a charging voltage with a voltage value corresponding to the voltage demand signal.

2. The battery module control method as described in claim 1, characterized in that, Between the steps of acquiring the voltage values ​​of N auxiliary battery packs and the vehicle status information of the electric vehicle, and the step of controlling all auxiliary battery packs to connect to the discharge terminal when it is determined from the vehicle status information that the electric vehicle is in a driving state and the voltage difference between the voltage value of any auxiliary battery pack and a preset voltage value is less than a first preset voltage difference, the battery module control method further includes: Obtain the number of auxiliary battery packs within the battery module; If the number of auxiliary battery packs is equal to one, obtain the voltage value of the main battery pack, and configure the preset voltage value as the voltage value of the main battery pack; If the number of auxiliary battery packs is greater than one, the preset voltage value is configured to be the voltage value of any other auxiliary battery pack.

3. The battery module control method as described in claim 1, characterized in that, The specific steps of controlling the N auxiliary battery packs to be connected to the discharge terminal one at a time are as follows: Sort the N auxiliary battery packs in descending order of voltage value; The auxiliary battery pack with the highest control voltage value is connected to the discharge terminal; When the voltage difference between the voltage value of the auxiliary battery pack connected to the discharge terminal and the voltage value of the auxiliary battery pack with the second highest voltage value is less than a first preset voltage difference, the auxiliary battery pack with the second highest voltage value is also connected to the discharge terminal, until all the auxiliary battery packs are connected to the discharge terminal.

4. The battery module control method as described in claim 3, characterized in that, After the step of controlling all the auxiliary battery packs to be connected to the discharge terminal, the battery module control method further includes: When the voltage of the auxiliary battery pack connected to the discharge terminal is lower than the preset high output voltage value and the electric vehicle is determined to be in an acceleration state according to the vehicle status information, the main battery pack is controlled to be connected to the discharge terminal together or the main battery pack is controlled to be connected to the discharge terminal alone. When it is determined from the vehicle status information that the electric vehicle has returned to cruise control, the main battery pack is controlled to disconnect from the electrical connection with the discharge terminal.

5. The battery module control method as described in claim 1, characterized in that, The battery module control method further includes: When it is determined from the vehicle status information that the electric vehicle is in a stationary state and the voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value is less than the preset stationary voltage difference, all the auxiliary battery packs are controlled to be connected to the discharge terminal. When it is determined from the vehicle status information that the electric vehicle is in a stationary state and there is a voltage difference between the voltage value of any of the auxiliary battery packs and the preset voltage value that is greater than the preset stationary voltage difference, the N auxiliary battery packs are controlled to be connected to the discharge terminal one by one in a sequential manner. Wherein, the preset static voltage difference is less than the first preset voltage difference.

6. The battery module control method as described in claim 1, characterized in that, The specific steps of controlling the main battery pack and the N auxiliary battery packs to be connected in series to the charging terminal one at a time are as follows: Sort the N auxiliary battery packs and the main battery packs in descending order of voltage value; The battery pack with the lowest voltage value among the auxiliary battery pack and the main battery pack is connected to the charging terminal. When the voltage difference between the battery pack connected to the charging terminal and the battery pack with the second lowest voltage value is less than a second preset voltage difference, the battery pack with the second lowest voltage value is also connected in series to the charging terminal, until the main battery pack and all the auxiliary battery packs are connected in series to the charging terminal.

7. A battery module for use in electric vehicles, characterized in that, The battery module includes: At least one auxiliary battery pack; Memory; A processor having a communication terminal for communicatively connecting with the electric vehicle; Charging end; Discharge terminal; Switch array; A battery module control program stored in the memory and executed by the processor, wherein the battery module control program, when executed by the processor, implements the battery module control method as described in any one of claims 1-6; The processor is electrically connected to N auxiliary battery packs, the switch array, and the memory, respectively; the switch array is electrically connected to N auxiliary battery packs, the discharge terminal, and the charging terminal, respectively.

8. The battery module as described in claim 7, characterized in that, The battery module also includes: The main battery pack is electrically connected to the processor and the switch array, respectively.

9. The battery module as described in claim 7, characterized in that, The processor has a second communication terminal for establishing a communication connection with the charging pile.

10. An electric vehicle, characterized in that, Includes the battery module as described in any one of claims 7-9.

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