A BATTERY MODULE CHARGING AND DISCHARGING CONTROL METHOD AND A BATTERY SYSTEM

Abstract

A battery module charging and discharging control method comprising: determining the charging priority of battery modules in a battery system; raising the charging priority of the battery modules that are more difficult to unload, load, and/or replace; lowering the charging priority of the battery modules that are easier to unload, load, and/or replace; causing the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during the charging control of the battery modules; determining the discharging priority of the battery modules; raising the discharging priority of the battery modules that are easier to unload, load, and/or replace; and lowering the discharging priority of the battery modules that are more difficult to unload, load, and/or replace; causing the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during the discharging control of the battery modules.

Claims

1. A battery module charging and discharging control method, comprising: determining, by a controller, a charging priority of each of a plurality of battery modules in a battery system, comprising at least one of: raising the charging priority of the battery modules that are difficult to unload, load, or replace; and lowering the charging priority of the battery modules that are easy to unload, load, or replace; causing, by the controller, the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging; determining, by the controller, a discharging priority of each of the plurality of battery modules, comprising at least one of: raising the discharging priority of the battery modules that are easy to unload, load, or replace; and lowering the discharging priority of the battery modules that are difficult to unload, load, or replace; and causing, by the controller, the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging.

2. The method according to claim 1, wherein the causing of the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging comprising: causing the battery modules with higher charging priority to be charged with relative charging current intensities greater than those for the battery modules with lower charging priority; wherein the relative charging current intensity being a ratio of a charging current intensity of a battery module to an energy storage capacity of the battery module.

3. The method according to claim 1, wherein the causing of the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging comprising: stopping or refraining from charging the battery modules with lower charging priority while charging the battery modules with higher charging priority.

4. The method according to claim 1, further comprising: causing, by the controller, the battery modules with higher discharging priority to discharge so as to charge the battery modules with higher charging priority.

5-10. (canceled)

11. The method according to claim 1, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

12. The method according to claim 2, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

13. The method according to claim 3, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

14. The method according to claim 4, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

15. The method according to claim 1, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: stopping or refraining from discharging the battery modules with lower charging priority while discharging the battery modules with higher discharging priority.

16. The method according to claim 2, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: stopping or refraining from discharging the battery modules with lower charging priority while discharging the battery modules with higher discharging priority.

17. The method according to claim 3, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: stopping or refraining from discharging the battery modules with lower charging priority while discharging the battery modules with higher discharging priority.

18. The method according to claim 4, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: stopping or refraining from discharging the battery modules with lower charging priority while discharging the battery modules with higher discharging priority.

19. A battery system module charging and discharging control method, comprising: a plurality of battery modules; and a controller for determining a charging priority of each of the plurality of battery modules, the determination of the charging priority comprising at least one of: raising the charging priority of the battery modules that are difficult to unload, load, or replace; and lowering the charging priority of the battery modules that are easy to unload, load, or replace; wherein the controller is further configured to cause the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging; wherein the controller is further configured to determine a discharging priority of each of the plurality of battery modules, the determination of the discharging priority comprising at least one of: raising the discharging priority of the battery modules that are easy to unload, load, or replace; and lowering the discharging priority of the battery modules that are difficult to unload, load, or replace; and wherein the controller is further configured to cause the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging.

20. The system according to claim 19, wherein the causing of the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging comprising: causing the battery modules with higher charging priority to be charged with relative charging current intensities greater than those for the battery modules with lower charging priority; wherein the relative charging current intensity being a ratio of a charging current intensity of a battery module to an energy storage capacity of the battery module.

21. The system according to claim 19, wherein the controller is further configured to: cause the battery modules with higher discharging priority to discharge so as to charge the battery modules with higher charging priority.

22. The system according to claim 19, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

23. The system according to claim 20, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

24. The system according to claim 21, wherein the causing of the battery modules with higher discharging priority to take precedence over the battery modules with lower discharging priority during discharging comprising: causing the battery modules with higher discharging priority to be discharged with relative discharging current intensities greater than those for the battery modules with lower discharging priority; and stopping or refraining from discharging the battery modules with lower discharging priority while discharging the battery modules with higher discharging priority; wherein the relative discharging current intensity being a ratio of a discharging current intensity of a battery module to an energy storage capacity of the battery module.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Embodiments of the invention are described in more detail hereinafter with reference to the drawings, in which:

[0022] FIG. 1 is a block diagram of the conventional battery system;

[0023] FIG. 2 is a block diagram of a battery system in accordance with an embodiment of the present invention; and

[0024] FIG. 3 is a flowchart of a battery module charging and discharging control method in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0025] In the following description, battery systems and methods of charging and discharging battery and the likes are set forth as preferred examples. It will be apparent to those skilled in the art that modifications, including additions and/or substitutions may be made without departing from the scope and spirit of the invention. Specific details may be omitted so as not to obscure the invention; however, the disclosure is written to enable one skilled in the art to practice the teachings herein without undue experimentation.

[0026] In accordance with an embodiment of the present invention, the battery system comprises a plurality of battery modules that can be independently unloaded and loaded. As shown in FIG. 2, the plurality of battery modules are arranged in m rows by n columns, and housed in a container. For example, when a battery system is used in an electric vehicle, battery modules are housed in a specific container of the electric vehicle. Of course, the battery system can also be applied to other fields, such as those of electronic equipment, instruments, meters, and machineries.

[0027] The battery system of the present invention is also provided with a controller 10, which controls the charging and/or discharging of the plurality of battery modules. In particular, the controller 10 determines the charging and/or discharging priority of each battery module according to the unloading, loading, and/or replacement difficulty of each battery module, and determines the charging and/or discharging of each battery module according to the charging priority and/or discharging priority of each battery module.

[0028] In this embodiment, the battery modules are arranged in m rows by n columns, of which the first row of battery modules, i.e., [1, 1], [1, 2], . . . , [1, n], are located in the uppermost positions of the container, the second row of battery modules, i.e., [2, 1], [2, 2], . . . , [2, n], are located in the second uppermost positions of the container, and the last row of battery modules, i.e., [m, 1], [m, 2], . . . , [m, n], are located in the lowest positions of the container, and so on.

[0029] Furthermore, as the top of the container is the opening for battery modules' unloading, loading, and/or replacement, the unloading, loading, and/or replacement of the battery modules located at the top, i.e., [1, 1], [1, 2], . . . , [1, n], is easiest. The unloading, loading, and/or replacement of the second row of battery modules, i.e., [2, 1], [2, 2], . . . , [2, n], is slightly more difficult than that of the first row of battery modules; the unloading, loading, and/or replacement of the last row of battery modules, i.e., [m, 1], [m, 2], . . . , [m, n], is most difficult; and the unloading, loading, and/or replacement difficulty of the second last row of battery modules, i.e., [m−1, 1], [m−1, 2], . . . , [m−1, n], is only next to that of the last row of battery modules.

[0030] Each row may be provided with only one battery module in the battery system. In the case where the opening for unloading and/or loading is located at the top of the container, the unloading, loading, and/or replacement of the battery module located at the top is the easiest, whereas the unloading, loading, and/or replacement of the battery module located at the bottom is most difficult, and the difficulty of the unloading, loading, and/or replacement of the battery modules varies with their positions in the container. In this case, the charging and/or discharging priority may still be determined for each battery module according to said principle.

[0031] The main philosophy of the present invention is to minimize the frequencies of unloading, loading, and/or replacement of the battery modules that are more difficult to unload, load, and/or replace, and allow more frequent unloading, loading, and/or replacement of the battery modules that are easier to unload, load, and/or replace. This reduces the labor required for battery module unloading, loading, and/or replacement and improves the battery module charging and/or replacement efficiency. Thus, the plurality of battery modules must first be ranked. In other words, the charging and/or discharging priority of each battery module must be determined according to the unloading, loading, and/or replacement difficulty of each battery module.

[0032] FIG. 3 is a flowchart of the method in which a controller 10 controls the charging and discharging of a plurality of battery modules, wherein step S1 is to determine the charging priority and discharging priority of a plurality of battery modules. In this embodiment, the controller 10 determines each battery module's charging priority according to its position, i.e., according to its unloading, loading, and/or replacement difficulty. For example, the charging priority of the battery modules that are more difficult to unload, load, and/or replace is higher, whereas the charging priority of the battery modules that are easier to unload, load, and/or replace is lower. Therefore, in the battery system as shown in FIG. 2, the charging priority of the last row of battery modules, i.e., [m, 1], [m, 2], . . . , [m, n], is the highest, the charging priority of the second last row of battery modules, i.e., [m−1, 1], [m−1, 2], . . . , [m−1, n], is next only to that of the last row of battery modules, the charging priority of the first row of battery modules, i.e., [1, 1], [1, 2], . . . , [1, n], is the lowest, and so on.

[0033] Of course, the charging priority of the battery modules is not necessarily determined only according to their unloading, loading, and/or replacement difficulty. The goal of the present invention, nonetheless, is realized by raising the charging priority of the battery modules that are more difficult to unload, load, and/or replace, and/or lowering the charging priority of the battery modules that are easier to unload, load, and/or replace.

[0034] Furthermore, the controller 10 also determines the discharging priority of each battery module according to its position. Contrary to the charging priority's determination method, among a plurality of battery modules, the discharging priority of the battery modules that are more difficult to unload, load, and/or replace is lower, whereas the discharging priority of the battery modules that are easier to unload, load, and/or replace is higher. For example, in the battery system as shown in FIG. 2, the discharging priority of the first row of battery modules, i.e., [1, 1], [1, 2], . . . , [1, n], is the highest, the discharging priority of the second row of battery modules, i.e., [2, 1], [2, 2], . . . , [2, n], is next only to that of the first row of battery modules, the discharging priority of the last row of battery modules, i.e., [m, 1], [m, 2], . . . , [m, n], is the lowest, and so on.

[0035] Of course, the discharging priority of the battery modules is not necessarily determined only according to their unloading, loading, and/or replacement difficulty. The goal of the present invention, nonetheless, is realized by raising the discharging priority of the battery modules that are easier to unload, load, and/or replace, and/or lowering the discharging priority of the battery modules that are more difficult to unload, load, and/or replace.

[0036] After the determination of the charging and discharging priority of each battery module, if the controller 10 determines in step S2 that the battery system needs charging, the controller 10 will control the charging of each battery module according to its charging priority in step S3 such that the battery modules with higher charging priority will take precedence over the battery modules with lower charging priority during charging.

[0037] In accordance with one embodiment of the present invention, the causing of the battery modules with higher charging priority to take precedence over the battery modules with lower charging priority during charging can be realized as follows: control the charging current such that the relative charging current intensities of the battery modules with higher charging priority are greater than those of the battery modules with lower charging priority. As the energy storage capacities of different battery modules may not be the same, if the same charging current intensity is provided, the states of charge of the battery modules with smaller energy storage capacities will increase at higher rates, whereas the states of charge of the battery modules with larger energy storage capacities will increase at lower rates. Thus, if higher charging current intensities are simply provided to the battery modules with higher charging priority without considering their energy storage capacities, it is possible that the states of charge of the battery modules with higher charging priority may still increase at lower rates in case of their energy storage capacities being larger. Therefore, it is necessary that higher relative charging current intensities be provided to the battery modules with higher charging priority.

[0038] Therefore, in accordance with one embodiment of the present invention, higher relative charging current intensities are provided to the battery modules with higher charging priority and lower relative charging current intensities are provided to the battery modules with lower charging priority. The relative charging current intensity of the present invention is the ratio of the charging current intensity provided to a battery module to the energy storage capacity of the battery module. The higher charging priority the battery modules have, the higher relative charging current intensities they can obtain.

[0039] In accordance with the aforesaid embodiment, the battery modules that are most difficult to unload, load, and/or replace (e.g., the last row of battery modules in the battery system as shown in FIG. 2) receive the highest relative charging current intensities. The first row of battery modules receive the lowest relative charging current intensities, and the relative charging current intensities received by the second row of battery modules are slightly higher than those received by the first row of battery modules, and so on.

[0040] In accordance with another embodiment, while charging the battery modules with higher charging priority, the control method causes to stop or refrain from charging the battery modules with lower charging priority. Thus, after conducting step S2, if the controller 10 determines that the battery system needs charging, the controller 10 conducts step S3, which provides higher relative charging current intensities to the battery modules with higher charging priority, and either provides lower relative charging current intensities to the battery modules with lower charging priority or stops or refrains from charging the battery modules with lower charging priority.

[0041] Similarly, when the controller 10 controls the discharging of a plurality of battery modules, it also determines the discharging current intensity of each battery module according to the battery module's energy storage capacity and discharging priority such that the relative discharging current intensities of the battery modules with higher discharging priority are greater than those of the battery modules with lower discharging priority. The relative discharging current intensity is the ratio of the discharging current intensity drawn from a battery module to the energy storage capacity of the battery module. Therefore, the battery modules that are most difficult to unload, load, and/or replace (e.g., the last row of battery modules in the battery system as shown in FIG. 2) have the lowest relative discharging current intensities, whereas the battery modules which are easiest to unload, load, and/or replace (e.g., the first row of battery modules in the battery system as shown in FIG. 2) have the highest relative discharging current intensities, and the relative discharging current intensities of the second row of battery modules are slightly lower than those of the first row of battery modules, and so on.

[0042] In accordance with yet another embodiment, while discharging the battery modules with higher discharging priority, the control method causes to stop or refrain from discharging the battery modules with lower discharging priority. Thus, after conducting step S4, if the controller 10 determines that the battery system needs discharging, the controller 10 conducts step S5, which causes the battery modules with higher discharging priority to output higher relative discharging current intensities, and either causes the battery modules with lower discharging priority to output lower relative discharging current intensities or stops or refrains from discharging the battery modules with lower discharging priority.

[0043] In addition, the control method can also cause the battery modules with higher discharging priority to discharge so as to charge the battery modules with higher charging priority.

[0044] As the battery modules with higher discharging priority are usually those that are easier to unload, load, and/or replace, such as the first and second rows of battery modules in the battery system as shown in FIG. 2, whereas the battery modules with higher charging priority are usually those that are more difficult to unload, load, and/or replace, such as the last row of battery modules in FIG. 2, causing the battery modules with higher discharging priority to discharge so as to charge the battery modules with higher charging priority is functionally equivalent to the battery modules with higher discharging priority in the battery system discharging so as to charge the battery modules with higher charging priority in the battery system, for the realization of charging of such battery modules with higher charging priority.

[0045] In accordance with various embodiments, charging priority is given to the battery modules in the battery system that are more difficult to unload, load, and/or replace, but in the discharging process, discharging priority is not given to such battery modules, so that the states of charge of the battery modules that are more difficult to unload, load, and/or replace are increased, and the probability of their unloading for the purpose of charging and/or replacement is significantly decreased. On the other hand, discharging priority is given to the battery modules that are easier to unload, load, and/or replace, but in the charging process, charging priority is not given to such battery modules, so that the states of charge of the battery modules that are easier to unload, load, and/or replace are decreased, and the probability of their unloading for the purpose of charging and/or replacement is increased. The unloading, loading, and/or replacement of the battery modules that are easier to unload, load, and/or replace are less difficult and require less labor and time. Ultimately, the control methods in accordance with the embodiments of the present invention reduce the overall effort required for the unloading, loading, and/or replacement of battery modules during the use of the battery system, and improve the charging efficiency of battery systems of which the battery modules cannot be charged without their unloading.

[0046] For electrical equipment that has high power consumption and battery systems of large sizes, such as electric vehicles, large portable electrical equipment, etc., the methods of the present invention can improve the usage efficiency of the battery systems and bring great convenience to the users.

[0047] The above-described embodiments are set forth as preferred exemplary embodiments of the present invention. It is possible to arrive at variations in other practical applications without departing from the scope of the present invention. For example, in the battery system as shown in FIG. 2, if the opening for battery module loading and/or unloading is located on the left side of the container rather than at the top, then the first column of battery modules, i.e., [1, 1], [2, 1], [m, 1], are easiest to unload, load, and/or replace. Accordingly, the first column battery modules have the lowest charging priority and/or the highest discharging priority. Meanwhile, the last column battery modules, i.e., [1, n], [2, n], . . . , [m, n], are most difficult to unload, load, and/or replace, and accordingly, the last column battery modules have the highest charging priority and/or the lowest discharging priority, and so on.

[0048] In the aforesaid cases, the relative charging current intensity and/or the relative discharging current intensity of each battery module can be determined and/or the charging and/or discharging of different battery modules can be controlled according to the above-described methods. This is to realize higher charging priority and/or lower discharging priority of the battery modules that are more difficult to unload, load, and/or replace; and/or to realize higher discharging priority and/or lower charging priority of the battery modules that are easier to unload, load, and/or replace. This way, the objectives of the present invention are realized.

[0049] Moreover, in other possible cases, the container may be provided with two or more openings for battery module loading and/or unloading. If the container is provided with a plurality of openings for battery module loading and/or unloading, the unloading, loading, and/or replacement difficulty is to be determined according to the loading position of each battery module and the position of each opening for loading and/or unloading. Lastly, in addition to the loading positions of battery modules and the position(s) of the opening(s) for loading and/or unloading, other factors that may determine the unloading, loading, and/or replacement difficulty of each battery module are not excluded by the above-described embodiments of the present invention.

[0050] The foregoing description of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art.

[0051] The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications that are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalence.