Patent Description:
With the rapid growth of new energy vehicles in the automotive market, the use of battery technologies to provide electric energy as a power source has become a mainstream technology for the development of new energy vehicle technologies. Generally, a battery used as a power source in a new energy vehicle is usually a battery pack composed of a plurality of battery cells, but the battery shows significant performance degradation after long-period, high-rate, and multi-depth charging and discharging cycles on the vehicle. Specifically, after the battery is charged and discharged for a period of time, voltages of various battery cells fluctuate or battery capacities thereof are unbalanced, and sometimes a battery cell may even be damaged, resulting in failure of the entire battery pack. In practical application, performance degradation of a battery comprises recoverable performance degradation and non-recoverable performance degradation. Battery maintenance can recover part of the battery capacity, extend the battery service life, and improve the battery performance.

In an existing battery maintenance scheme, a battery is maintained when a cruising time of a vehicle is significantly decreased, battery faults occur frequently, or the battery may have been at non-recoverable performance degradation. This battery maintenance scheme is a passive maintenance method and tends to shorten the battery service life. In addition, users need to go to a designated maintenance site for battery maintenance, which is not flexible. Therefore, the users are reluctant to maintain batteries, and have a poor user experience. The Chinese Patent publication <CIT> discloses a electrokinetic cell repair system. United States patent publication <CIT> discloses a system and method for determining performance degradation of a battery system. United States patent publication <CIT> discloses an apparatus and method for regulating a state of charge of an electrical energy storage. The Canadian patent publication <CIT> discloses a service life control for energy stores.

Therefore, how to propose a solution for actively maintaining a battery and improving user experience is a problem that those skilled in the art need to solve at present.

In order to solve the problems in the prior art, that is, to solve the problems that a traction battery is passively maintained and the maintenance method is not flexible in the prior art, a first aspect of the invention provides a traction battery maintenance method, which comprises:.

In a preferred implementation of the above method, the step of "performing cyclic charging and discharging on the traction battery multiple times" comprises:.

In a preferred implementation of the above method, the maintenance strategy comprises:.

In a preferred implementation of the above method, before the step of "generating a maintenance scheme for the traction battery based on the maintenance strategy", the method further comprises:.

In a preferred implementation of the above method, before the step of "generating the maintenance scheme for the traction battery based on the maintenance strategy, the travelling path, the trip time, and the available maintenance terminal", the method further comprises:.

In a preferred implementation of the above method, after the step of "generating a maintenance scheme for the traction battery based on the maintenance strategy", the method further comprises:
acquiring an update instruction of the maintenance scheme, and regenerating a maintenance scheme for the traction battery based on a maintenance time and a maintenance terminal specified by the update instruction of the maintenance scheme.

In a preferred implementation of the above method, the maintenance terminal is a battery swap station or a mobile battery swap station or a vehicle repair station.

A second aspect of the invention provides a traction battery maintenance apparatus, which comprises:.

In a preferred implementation of the above apparatus, the maintenance strategy further comprises:.

In a preferred implementation of the above apparatus, the maintenance strategy comprises:.

In a preferred implementation of the above apparatus, the acquisition unit is further configured to:.

In a preferred implementation of the above apparatus, the acquisition unit is further configured to acquire an added value corresponding to the maintenance strategy; and
the generation unit is further configured to generate the maintenance scheme for the traction battery based on the maintenance strategy, the travelling path, the trip time, the available maintenance terminal, and the added value.

In a preferred implementation of the above apparatus, the generation unit comprises an update subunit, and the update subunit is configured to:
acquire an update instruction of the maintenance scheme, and regenerate a maintenance scheme for the traction battery based on a maintenance time and a maintenance terminal specified by the update instruction of the maintenance scheme.

In a preferred implementation of the above apparatus, the maintenance terminal is a battery swap station or a mobile battery swap station or a vehicle repair station.

A third aspect of the invention provides a server, which comprises the traction battery maintenance apparatus described above, and
further comprises:
a transceiver unit configured to receive battery state data and a maintenance feedback request from a user terminal, and send, to the user terminal when the maintenance feedback request is a confirmation instruction, a maintenance scheme generated by the traction battery maintenance apparatus.

A fourth aspect of the invention provides a traction battery maintenance system, which comprises the server and the maintenance terminal that are described above.

In a preferred implementation of the above system, the traction battery maintenance system further comprises a user terminal configured to receive a maintenance scheme sent by the server, and send a maintenance confirmation instruction to the server, wherein
the server is further configured to send the maintenance scheme to the maintenance terminal according to the maintenance confirmation instruction.

In a preferred implementation of the above system, the user terminal is further configured to receive performance improvement information of the traction battery that is sent by the server based on the maintenance data.

In a preferred implementation of the above system, the user terminal is an automotive head unit or a mobile terminal.

A fifth aspect of the invention provides a storage apparatus in which a plurality of programs are stored, and the programs are adapted to be loaded by a processor to perform the above-mentioned traction battery maintenance method.

Compared with the closest prior art, the technical solutions of the invention have at least the following beneficial effects:.

To make the objectives, technical solutions, and advantages of the embodiments of the invention clearer, the technical solutions in the embodiments of the invention will be described clearly and completely in conjunction with the drawings in the embodiments of the invention. Obviously, the described embodiments are only some, rather than all of the embodiments of the invention. Based on the embodiments of the invention, all other embodiments obtained by those of ordinary skills in the art without going through any creative work shall fall within the protection scope of the invention.

Preferred implementations of the invention are described below with reference to the drawings. It should be understood by those skilled in the art that these implementations are only for explaining the technical principles of the invention and are not intended to limit the protection scope of the invention.

Referring to <FIG> illustrates main steps of a first traction battery maintenance method in this embodiment. As shown in <FIG>, the first traction battery maintenance method in this embodiment comprises the following steps:
Step S <NUM>: acquiring a health degree of a traction battery.

Specifically, the health degree of the traction battery is a comprehensive representation factor of battery health. During long-term use, the battery inevitably undergoes aging and deterioration. In order to reasonably assess the remaining use time of the battery, it is necessary to acquire the health degree of the traction battery. In this embodiment of the invention, the health degree of the traction battery can be a state of health (SOH) of the battery or other parameters that can represent the battery health, which is not limited in the invention. For convenience of description, the invention is described below by using an example in which the health degree of the battery is an SOH.

The state of health (SOH) of the battery is the comprehensive representation factor of the battery health. The SOH of the battery is a ratio of a capacity discharged by the traction battery from a fully charged state to a cut-off voltage at a certain rate to its corresponding nominal capacity under standard conditions. Generally, after a battery has been used for a period of time, a ratio of a measured actual value of a performance parameter to a nominal value thereof can be used directly or indirectly to determine a state of health of the battery and measure a health degree of the battery.

In this embodiment of the invention, the health degree of the traction battery may be acquired through a plurality of methods and a plurality of parameter values, so that a state of health of the traction battery can be monitored in real time. An example in which the health degree of the traction battery is an SOH is used, a value of the SOH can be calculated through methods such as a direct discharge method, an internal resistance method, an electrochemical impedance analysis method, and a model method, or can be calculated from the perspective of SOH definition. Calculation can be performed by using various parameters such as charging duration of the battery, changes in a voltage varying with the SOH, and a resistance value, wherein related parameters may be actively reported by a vehicle where the traction battery is located, or may be acquired by a maintenance terminal and uploaded to a backend server when the vehicle is charged at the maintenance terminal. Since content of SOH calculation has been disclosed in the prior art, a detailed description is not provided herein.

Step S <NUM>: acquiring a state of health of the traction battery based on the health degree of the traction battery.

After the health degree of the traction battery is obtained, the state of health of the traction battery can be calculated based on a change rate of the health degree of the traction battery. Different states of health comprise: a state of the traction battery when the change rate of the health degree of the traction battery is greater than a preset change rate threshold, and a state of the traction battery when the change rate of the health degree of the traction battery is less than or equal to the preset change rate threshold and the health degree is a specific value, wherein the specific value comprises at least one numerical value.

Specifically, an example in which the health degree of the traction battery is an SOH is used for description. With the long use of the battery, the SOH of the battery rapidly degrades, for example, in cases where fast charging is performed on the battery for a long time, and the vehicle travels in bad road conditions for a long time. Existing batteries needs to be maintained after an SOH degrades to less than <NUM>%, but when the SOH of the battery degrades to less than <NUM>%, the maintenance requires more resources, and it will take a longer time to maintain the battery. For a maintenance terminal, a higher tolerance for efficiency is required.

In this embodiment of the invention, when the SOH of the battery degrades to <NUM>%, a change rate of the SOH of the battery may be compared with a preset determination threshold. If the change rate of the SOH of the battery is greater than the preset determination threshold, it may be considered that the traction battery is in a first state of health, where the preset determination threshold may range from <NUM> to <NUM>; if the SOH of the battery has not degraded to less than <NUM>%, that is, the change rate of the SOH of the battery is within a normal change range of the SOH, when a value of the SOH value is a specific value, specifically, the SOH may range from <NUM>% to <NUM>%, a plurality of nodes may be set. For convenience of description, this embodiment of the invention is described by using an example in which the number of nodes is <NUM>. When the SOH of the battery is [s1, s2, s3, s4, s5] and is the same as a value of any one of the nodes, where values of [s1, s2, s3, s4, s5] may be [<NUM>, <NUM>, <NUM>, <NUM>, <NUM>], it may be considered that the traction battery is in a second state of health.

A specific calculation method of the change rate of the SOH may be as shown in formula (<NUM>): <MAT>.

Mt represents a change rate of the SOH at a time t, ΔSOH represents a change value of the SOH at the time t relative to an initial time, and Δt represents a change value of the time at the time t relative to the initial time.

Step S <NUM>: matching a maintenance strategy corresponding to the state of health of the traction battery based on a one-to-one correspondence between different states of health and different maintenance strategies.

In this embodiment of the invention, there is a one-to-one correspondence between different states of health and different maintenance strategies, and the maintenance strategy corresponding to the state of health of the traction battery can be matched based on the state of health. The maintenance strategy of the traction battery comprises performing cyclic charging and discharging on the traction battery multiple times, wherein a charging current, a discharging current, and the number of cycles of the cyclic charging and discharging performed multiple times depend on the state of health of the traction battery.

Referring to <FIG> illustrates a current change process in single maintenance of a traction battery, and <FIG> illustrates a current change process in cyclic maintenance of a traction battery. As shown in <FIG>, the time period t1-t2 represents a discharging process, the time period t2-t3 represents a resting process, and the time period t3-t4 represents a charging process. As shown in <FIG>, t1-t4 represents a first cyclic charging and discharging process, and t5-t8 represents a second cyclic charging and discharging process.

Performing cyclic charging and discharging on the traction battery multiple times comprises the following steps:
Charging step: performing constant current charging on the traction battery with a preset charging current when a voltage of a battery cell in the traction battery is less than a preset voltage, and performing constant voltage charging on the traction battery when the voltage of the battery cell reaches the preset voltage, gradually reducing the charging current, and stopping charging when the charging current is less than a preset current.

Discharging and resting step: performing constant current discharging on the traction battery with a preset discharging current until a state of charge of the traction battery is <NUM>, and resting the traction battery for a certain period of time after the state of charge is <NUM>.

Cycle steps: repeatedly performing the charging step and the discharging and resting step for a preset number of cycles.

It should be noted that the sequence of the charging step and the discharging and resting step is not limited in this embodiment of the invention. In practical application, a traction battery may be discharged first, and after the discharging ends, the traction battery is rested for a certain period of time, and then the traction battery is charged.

When the change rate of the health degree of the traction battery is greater than the preset change rate threshold, the charging current is a first value, the discharging current is a second value, and the number of cycles is a first preset value in the maintenance strategy; and.

Maintenance strategy R1 corresponding to the first state of health of the traction battery:.

Discharging, resting, and charging of the battery pack may be considered as a maintenance cycle, and the maintenance strategy R1 needs to involve <NUM> to <NUM> cycles.

Maintenance strategy R2 corresponding to the second state of health of the traction battery:.

Discharging, resting, and charging of the battery pack may be considered as a maintenance cycle, and the maintenance strategy R2 needs to involve <NUM> to <NUM> cycles.

A value of Vm can be set depending on specific conditions of the battery, which is not limited herein.

In the maintenance strategy R1, the charging current corresponds to the first value, the discharging current corresponds to the second value, and the number of cycles corresponds to the first preset value. In the maintenance strategy R2, the charging current corresponds to the third value, the discharging current corresponds to the fourth value, and the number of cycles corresponds to the second preset value.

In addition, when a retention rate of a battery capacity is less than <NUM>%, while the change rate of the SOH of the battery is less than the preset determination threshold, a general maintenance strategy may be used to reduce control parameters for the maintenance of the traction battery by the maintenance terminal, and improve the utilization of resources. The general maintenance strategy is specifically as follows:.

Discharging, resting, and charging of the battery pack may be considered as a maintenance cycle, and the general maintenance scheme needs to involve <NUM> to <NUM> cycles.

Step S104: generating a maintenance scheme for the traction battery based on the maintenance strategy.

Specifically, this step is described below in conjunction with three solutions:
First solution: the maintenance scheme for the traction battery is generated based on the maintenance strategy, a travelling path of the vehicle, a trip time, and a maintenance terminal.

During a travelling process of the vehicle, the vehicle uploads habit data of a user to a backend server, wherein the habit data of the user may be location data of the vehicle, use time data of the vehicle, etc., and a daily driving route and a trip time of the user is analysed based on the habit data of the user. After the state of health of the traction battery is obtained, the corresponding maintenance strategy is obtained with reference to a maintenance strategy matching table, a location of a maintenance terminal that is on the daily driving route of the user or close to the daily driving route of the user is provided in conjunction with the maintenance strategy, and maintenance of the traction battery is recommended to the user during free time of the user. The maintenance terminal may be a battery swap station or a mobile battery swap station or a vehicle repair station. According to vehicle usage habits of the user, the maintenance scheme is flexibly provided during a use process of the user, which is in line with the living habits of the user and improves user experience.

Second solution: the maintenance scheme for the traction battery is generated based on the maintenance strategy, the travelling path, the trip time, the maintenance terminal, and an added value.

After the state of health of the traction battery is obtained, the corresponding maintenance strategy is obtained with reference to the maintenance strategy matching table, and a corresponding added value is set based on time spent in maintenance and electric energy consumed in maintenance that are involved in the maintenance strategy. For example, the added value may be accumulated maintenance points, etc., and users can exchange accumulated maintenance points for a certain charging time or for goods, etc. The maintenance scheme for the traction battery is generated based on the maintenance strategy, the travelling path, the trip time, and the maintenance terminal in conjunction with the added value, so that enthusiasm of a user for traction battery maintenance can be motivated.

Third solution: a new maintenance scheme is regenerated according to an update instruction.

In this embodiment of the invention, an application can be installed in the vehicle or a mobile terminal (such as a mobile phone and a tablet computer) associated with the vehicle, and the backend server may generate the corresponding maintenance scheme based on the maintenance strategy, the travelling path, the trip time, the maintenance terminal, etc., and push the maintenance scheme to the user, but the user may want to modify the maintenance scheme due to their own actual situations. For example, an actual driving path of the user is far away from a location of the maintenance terminal provided in the maintenance scheme, or a trip time of the user conflicts with the maintenance time provided in the maintenance scheme. In this case, the user may select a location of a maintenance terminal or select a maintenance time as an update instruction, and send the update instruction to the backend server through the vehicle or the mobile terminal associated with the vehicle, and the backend server regenerates a maintenance scheme.

In practical application, the backend server can send the maintenance scheme to the application. After the user accepts the maintenance scheme in the application, the backend server can send the maintenance scheme to a maintenance terminal pushed by the backend server or selected by the user. The maintenance time reserves an appropriate time for the user according to an estimated maintenance time in the maintenance scheme, and maintains the battery based on the maintenance strategy. After the maintenance of the battery is completed, the backend server can send a maintenance result to the application, wherein the maintenance result may be a performance improvement index after the maintenance of the battery relative to before the maintenance of the battery.

Referring to <FIG> illustrates main steps of a second traction battery maintenance method in this embodiment. As shown in <FIG>, the second traction battery maintenance method in this embodiment comprises the following steps:
Step S201: acquiring, by a battery management platform, state data of a traction battery.

In this embodiment of the invention, the state data of the traction battery may be state of health data of the traction battery, and the state of health data of the traction battery may be used to analyse a state of health of the traction battery. Specifically, the battery management platform may accurately locate, in conjunction with the state of health data of the traction battery and a state of health analysis method of the traction battery, a traction battery whose state of health of the traction battery rapidly decreases and whose state of health level is relatively low.

The state of health data of the traction battery may be an SOH, and a user terminal may be a vehicle head unit or a mobile terminal. The method for acquiring the state data of the traction battery by the battery management platform may be that a vehicle where the traction battery is located actively reports or a maintenance terminal acquires and reports the state data when the vehicle is charged at the maintenance terminal. The maintenance terminal may be a battery swap station or a mobile battery swap station or a vehicle repair station.

Step S202: determining, by the battery management platform based on the state data of the traction battery, whether the traction battery needs to be maintained.

After receiving the state data of the traction battery, the battery management platform can determine the state of health of the traction battery based on the state data of the traction battery. For a specific determination method, reference can be made to related content in the embodiment of the first traction battery maintenance method described above, and details are not described here again. The battery management platform may be a backend server, which is configured to receive the state data and a maintenance request of the traction battery, and determines whether the traction battery needs to be maintained. If the traction battery needs to be maintained, the battery management platform sends a maintenance request to an operation management platform and step S203 is performed. If there is no need to maintain the traction battery, the traction battery is not maintained.

Step S203: receiving, by the operation management platform, the maintenance request from the battery management platform and scheduling a maintenance terminal.

The operation management platform may be a backend server. After receiving the maintenance request from the battery management platform, the operation management platform may schedule a maintenance terminal connected to the operation management platform. When a plurality of traction batteries need to be maintained, the operation management platform can schedule maintenance terminals based on state of health levels of the traction batteries, priorities of maintenance requests, or user levels. The method of scheduling a maintenance terminal may be as follows: making a reservation for a use time of the maintenance terminal and sending a maintenance strategy corresponding to a state of health of a battery to the maintenance terminal, according to a maintenance request. For the specific scheduling method, reference can be made to related content in the embodiment of the first traction battery maintenance method described above, and details are not described here again.

Step S204: determining, by the operation management platform, whether there is an available maintenance terminal.

First, the operation management platform determines whether there is an available maintenance terminal, that is, whether there is an unused maintenance terminal, or a maintenance terminal being used and an estimated use time, so that the maintenance terminal can be used for scheduling in time after maintenance of a traction battery is completed. If there is no available maintenance terminal, return to step S203 until an available maintenance terminal is found.

Then, a priority of a maintenance request is used as an example. When there are available maintenance terminals, the operation management platform can sequentially arrange related maintenance terminals to maintain traction batteries based on priorities of received maintenance requests, and a traction battery that sends a maintenance request first is preferentially maintained. A user level is used as an example. When there are available maintenance terminals, the operation management platform can sequentially arrange related maintenance terminals to maintain traction batteries based on user levels, and a traction battery with a higher user level is preferentially maintained.

In addition, it is also possible to arrange related maintenance terminals to maintain traction batteries based on user habits. For specific content, reference can be made to related content in the embodiment of the first traction battery maintenance method described above, and details are not described here again.

Step S205: maintaining, by the maintenance terminal, the traction battery.

An example in which the maintenance terminal is a battery swap station is used. With the help of a deployed battery swap network, a bidirectional charging and discharging module can be introduced into a charging slot of the battery swap station, and performance maintenance of the traction battery is implemented by performing cyclic charging and discharging on the traction battery under a corresponding procedure. In addition, for a specific maintenance method of the traction battery, reference can be made to related content in the embodiment of the first traction battery maintenance method described above, and details are not described here again.

Based on the embodiment of the first traction battery maintenance method described above, the invention further provides a traction battery maintenance apparatus. The traction battery maintenance apparatus is described below in conjunction with the drawings.

Referring to <FIG> illustrates a main structure of a traction battery maintenance apparatus in this embodiment. As shown in <FIG>, the traction battery maintenance apparatus in this embodiment comprises an acquisition unit <NUM>, a matching unit <NUM>, and a generation unit <NUM>.

The acquisition unit <NUM> is configured to acquire a state of health of a traction battery.

The matching unit <NUM> is configured to match a maintenance strategy corresponding to the state of health based on a preset one-to-one correspondence between different states of health and different maintenance strategies.

The generation unit <NUM> is configured to generate a maintenance scheme for the traction battery based on the maintenance strategy.

In a preferred implementation in this embodiment, the acquisition unit is further configured to:.

In a preferred implementation in this embodiment, the maintenance strategy comprises performing cyclic charging and discharging on the traction battery multiple times;
wherein a charging current, a discharging current, and the number of cycles of the cyclic charging and discharging performed multiple times depend on the state of health of the traction battery.

In a preferred implementation in this embodiment, the maintenance strategy further comprises:.

In a preferred implementation in this embodiment, the maintenance strategy comprises:.

In a preferred implementation in this embodiment, the acquisition unit <NUM> is further configured to:.

In a preferred implementation in this embodiment, the acquisition unit <NUM> is further configured to acquire an added value corresponding to the maintenance strategy; and
the generation unit <NUM> is further configured to generate the maintenance scheme for the traction battery based on the maintenance strategy, the travelling path, the trip time, the available maintenance terminal and the added value.

In a preferred implementation in this embodiment, the generation unit <NUM> comprises an update subunit, and the update subunit is configured to:
acquire an update instruction of the maintenance scheme, and regenerate a maintenance scheme for the traction battery based on a maintenance time and a maintenance terminal specified by the update instruction of the maintenance scheme.

In a preferred implementation in this embodiment, the maintenance terminal is a battery swap station or a mobile battery swap station or a vehicle repair station.

Based on the embodiment of the traction battery maintenance method described above, the invention further provides a server, and the server comprises the traction battery maintenance apparatus described above.

The server further comprises a transceiver unit, which is configured to receive battery state data and a maintenance feedback request from a user terminal, and send, to the user terminal when the maintenance feedback request is a confirmation instruction, a maintenance scheme generated by the traction battery maintenance apparatus.

Based on the embodiment of the traction battery maintenance method described above, the maintenance terminal comprises:.

Based on the embodiment of the traction battery maintenance method described above, the invention further provides a traction battery maintenance system, which comprises the server and the maintenance terminal that are described above.

In a preferred implementation in this embodiment, the traction battery maintenance system further comprises a user terminal, which is configured to receive a maintenance scheme sent by the server, and send a maintenance confirmation instruction to the server, wherein
the server is further configured to send the maintenance scheme to the maintenance terminal according to the maintenance confirmation instruction.

In a preferred implementation in this embodiment, the user terminal is further configured to receive performance improvement information of the traction battery that is sent by the server based on maintenance data.

In a preferred implementation in this embodiment, the user terminal is a vehicle head unit or a mobile terminal.

Based on the embodiment of the traction battery maintenance method described above, the invention further provides a storage device in which a plurality of programs are stored, and the programs are adapted to be loaded by a processor to perform the traction battery maintenance method in the above method embodiment.

It will be clearly understood by those skilled in the art that for convenience and brevity of the description, for the specific working process and related description of the traction battery maintenance apparatus, the traction battery maintenance system, the server, the maintenance terminal, the storage apparatus, and the processing apparatus in the embodiments of the invention, reference can be made to the corresponding process of the traction battery maintenance method in the above-mentioned embodiment, which have the same beneficial effects as the above method, and details are not described here again.

The method or algorithm steps described in conjunction with the embodiments disclosed herein may be implemented by hardware, a software module executed by a processor, or a combination of both. The software module may be arranged in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the technical field.

Those skilled in the art should be able to realize that the method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software or a combination of both. To clearly illustrate the interchangeability of electronic hardware and software, the compositions and steps of the various examples have been generally described in terms of functionality in the above description. Whether these functions are performed in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the invention, as defined by the independent claims.

It should be noted that, the terms "first", "second", and the like in the specification, claims, and drawings of the invention are intended to distinguish between similar objects, and are not intended to describe or indicate a particular order or sequence. It should be understood that the data termed in such a way are interchangeable in proper circumstances so that the embodiments of the invention described herein can be implemented in other orders than the order illustrated or described herein.

Claim 1:
A traction battery maintenance method, characterized by comprising:
acquiring (S102) a state of health of a traction battery;
matching (S103) a maintenance strategy corresponding to the state of health based on a preset one-to-one correspondence between different states of health and different maintenance strategies; and
generating (S104) a maintenance scheme for the traction battery based on the maintenance strategy,
wherein the step of "acquiring a state of health of a traction battery" comprises:
acquiring the state of health of the traction battery based on a change rate of a health degree of the traction battery; and
the different states of health comprise: the state of the traction battery when the change rate of the health degree of the traction battery is greater than a preset change rate threshold, and the state of the traction battery when the change rate of the health degree of the traction battery is less than or equal to the preset change rate threshold and the health degree is a specific value, wherein the specific value comprises at least one value,
characterized in that the maintenance strategy comprises performing cyclic charging and discharging on the traction battery multiple times,
wherein a charging current, a discharging current, and the number of cycles of the cyclic charging and discharging performed multiple times depend on the state of health of the traction battery.