Charging method and system for multiple battery packs

Abstract

The invention provides a multi-battery pack charging method and system. The method comprises the following steps: acquiring a request charging current and an actual charging current of each battery pack in a multi-battery pack system in real time; according to the request charging current and the actual charging current, whether overpower charging exists in the battery pack or not is determined; and if the overpower charging exists in any one battery pack in all the battery packs, reducing the system charging current of the multi-battery pack system according to a preset stepping value. The battery pack can be prevented from being in an overpower charging state, the service life of the battery is prolonged, and the charging efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of charging systems, and particularly relates to a charging method and system for multiple battery packs. Background Art

[0002] For a system for parallel charging of multiple battery packs, the system charging current is usually based on the maximum requested charging current among the multiple battery packs, or based on the requested charging current of the host battery pack. However, neither of the above two charging methods takes into account the charging status of other battery packs in the system, which easily causes the charging current to exceed the actual required current, reducing the lifespan of the battery packs, or failing to maximize the charging efficiency, resulting in an extended charging time. Summary of the Invention

[0003] The present invention provides a charging method and system for multiple battery packs, aiming to solve the problems that the current charging method for multiple battery pack systems easily reduces the lifespan of the battery packs and has a low charging efficiency.

[0004] In a first aspect, the present invention provides a charging method for multiple battery packs, the method comprising:

[0005] Obtaining in real time the requested charging current and the actual charging current of each battery pack in the multiple battery pack system;

[0006] Confirming whether the battery pack has over-power charging according to the requested charging current and the actual charging current;

[0007] If any one of all the battery packs has the over-power charging, reducing the system charging current of the multiple battery pack system according to a preset step value.

[0008] In a second aspect, the present invention provides a multiple battery pack system, the multiple battery pack system being configured with the charging method for multiple battery packs according to any one of the above.

[0009] The present invention discloses a charging method for multiple battery packs and a multiple battery pack system. The charging method for multiple battery packs includes obtaining in real time the requested charging current and the actual charging current of each battery pack in the multiple battery pack system; confirming whether the battery pack has over-power charging according to the requested charging current and the actual charging current; if any one of all the battery packs has the over-power charging, reducing the system charging current of the multiple battery pack system according to a preset step value. Embodiments of the present invention can obtain the requested charging current and the actual charging current of each battery pack, and confirm whether each battery pack has over-power charging according to the requested charging current and the actual charging current. When a battery pack has over-power charging, the system charging current is reduced to avoid the battery pack being in an over-power charging state for a long time, which can extend the service life of the battery pack and improve the charging efficiency. Brief Description of the Drawings

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0011] Figure 1 is a flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0012] Figure 2 is a first sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0013] Figure 3 is a second sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0014] Figure 4 is a third sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0015] Figure 5 is a fourth sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0016] Figure 6 is a fifth sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0017] Figure 7 is a sixth sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention;

[0018] Figure 8 is a seventh sub-flowchart of a charging method for a multi-battery pack provided by an embodiment of the present invention. Detailed Description of the Embodiments

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0020] It should be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of the described features, wholes, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, operations, elements, components, and / or their combinations.

[0021] It should also be understood that the terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms. It should be further understood that the term "and / or" used in the specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0022] In addition, the directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", "inside", "outside", "side", etc., are only with reference to the directions of the attached drawings and the usage state of the product. Therefore, the directional terms used are for explaining and understanding the present invention, rather than for limiting the present invention. In addition, in the drawings, structures that are similar or identical are denoted by the same reference numerals.

[0023] See Figure 1 , the present invention provides a charging method for a multi-battery pack. The charging method for the multi-battery pack can be applied to a multi-battery pack system for adjusting the charging current of each battery pack. The charging method for the multi-battery pack includes S110 - S130.

[0024] S110, obtain in real time the requested charging current and the actual charging current of each battery pack in the multi-battery pack system.

[0025] In an embodiment of the present invention, the multi-battery pack system may include a plurality of battery packs, a charge and discharge device, and a control device. The charge and discharge device is used to charge or discharge the battery packs, and the control device is used to control the operation of the multi-battery pack system. For example, it controls the charging and discharging of the charge and discharge device. The plurality of battery packs may include a main battery pack and a plurality of additional battery packs, and the specifications between different battery packs may be different.

[0026] When the multi-battery pack system is in a charging state, the requested charging current and the actual charging current of each battery pack can be obtained. The requested charging current refers to that each battery pack generates a charging current value according to its own state (such as battery level, temperature, etc.). The charging current value represents the magnitude of the charging current that the battery pack hopes to obtain in the current state. That is, the requested charging current is a demand signal sent by the battery pack to the multi-battery pack system for guiding the multi-battery pack system to adjust the system charging current. The actual charging current is the charging current of the current battery pack.

[0027] S120, confirm whether the battery pack has over-power charging according to the requested charging current and the actual charging current.

[0028] In an embodiment of the present invention, after obtaining the requested charging current and the actual charging current, it is determined whether there is over-power charging in the battery pack according to the requested charging current and the actual charging current. It can be understood that when determining whether there is over-power charging in the battery pack, all battery packs need to be determined, that is, each battery pack can be determined one by one, or determined in parallel. For example, if a multi-battery pack system includes a host pack, a first power supply pack, and a second power supply pack, then the multi-battery pack system has a total of three battery packs. When determining whether there is over-power charging, the requested charging power and the actual charging power of the host pack can be obtained first, and it can be determined whether there is over-power charging in the host pack. Then, the requested charging power and the actual charging power of the first power supply pack are obtained, and it is determined whether there is over-power charging in the first power supply pack. Finally, the requested charging power and the actual charging power of the second power supply pack are obtained, and it is determined whether there is over-power charging in the second power supply pack.

[0029] S130, if any one of all the battery packs has the over-power charging, the system charging current of the multi-battery pack system is reduced according to a preset step value.

[0030] In an embodiment of the present invention, when any one of all the battery packs has over-power charging, a preset step value can be obtained and the system charging current is reduced according to the preset step value. The preset step value is an empirical value, which represents the value of adjusting the system charging current each time. For example, the preset step value can be 5A. When adjusting the system charging current, 5A can be added or subtracted based on the current system charging current. The system charging current refers to the sum of the actual charging currents of each battery pack in the multi-battery pack system. For example, for a multi-battery pack system composed of a host pack, a first power supply pack, and a second power supply pack, if the actual charging current of the host pack is 30A, the actual charging current of the first power supply pack is 18A, and the actual charging current of the second power supply pack is 12A, then the current system charging current is 60A. When there is no over-power charging in the host pack, the first power supply pack, and the second power supply pack, the system charging current can be increased by a step value, for example, increased by 5A. Then the theoretical system charging current is 65A, and the newly added 5A charging current can be distributed to the host pack, the first power supply pack, and the second power supply pack according to a certain ratio. When any one of the host pack, the first power supply pack, and the second power supply pack has over-power charging, the system charging current can be reduced by a step value, for example, reduced by 5A. Then the theoretical system charging current is 55A, and the reduced 5A charging current is distributed to the host pack, the first power supply pack, and the second power supply pack according to a certain ratio, so as to reduce the actual charging currents of the host pack, the first power supply pack, and the second power supply pack respectively to avoid over-power charging for a long time.

[0031] See Figure 2, in some embodiments, such as in this embodiment, the multi-battery-pack charging method may further include steps S110a - S110b.

[0032] S110a, obtain the preset charging current of the multi-battery-pack system;

[0033] S110b, use the preset charging current as the system charging current to configure the charging current for each battery pack.

[0034] In the embodiments of the present invention, the preset charging current is the starting charging current, which is an empirical value and can be set by the staff according to different systems. For example, if the preset charging current is 5A, when the multi-battery-pack system starts charging, the system charging current is 5A, and then this 5A charging current is distributed to the corresponding battery packs according to the actual charging currents of different battery packs. It can be understood that the requested charging current can exceed the preset charging current. After the distribution of the preset charging current is completed, step S110 is entered to obtain the actual charging current and the requested charging current of each battery pack, and to confirm whether there is over-power charging of the battery pack. If not, the system charging current is increased according to the step value until the system current maximum value is reached or there is over-power charging of a battery pack.

[0035] For example, if the actual charging currents of the host pack, the first power-on pack, and the second power-on pack are 30A, 18A, and 12A respectively, and the preset charging current is increased by 5A, then according to the ratio of the actual charging currents of the host pack, the first power-on pack, and the second power-on pack, the 5A charging current is distributed to the host pack, the first power-on pack, and the second power-on pack. The ratio of the actual charging currents can be obtained from the actual charging currents of the host pack, the first power-on pack, and the second power-on pack. That is, the process of distributing the current is a slow dynamic process. Even if the distribution is not carried out, each battery pack will charge. Therefore, the actual charging current ratio can be confirmed according to the actual charging current of each battery pack, and the actual charging current ratio will not change significantly in a short time. For example, if the ratio of the actual charging currents of the host pack, the first power-on pack, and the second power-on pack is 5:3:2, then the charging current distributed to the host pack is 2.5A, the charging current distributed to the first power-on pack is 1.5A, and the charging current distributed to the second power-on pack is 1A. Before over-power charging occurs in the host pack, the first power-on pack, and the second power-on pack, the system charging current will increase step by step according to the step value, and the charging currents distributed to the host pack, the first power-on pack, and the second power-on pack will also increase accordingly.

[0036] See Figure 3 , in some embodiments, such as in this embodiment, the multi-battery-pack charging method may further include steps S141 - S145.

[0037] S141. If over-power charging does not exist in all the battery packs, obtain the actual charging current of the current system.

[0038] S142. Simulate an increase in the actual charging current of the system according to a preset step value to obtain a simulated current.

[0039] S143. Configure a charging current for each battery pack according to the simulated current to obtain the estimated actual current of each battery pack.

[0040] S144. Confirm whether over-power charging exists in the battery pack according to the requested charging current and the estimated actual current.

[0041] S145. If over-power charging does not exist in all the battery packs, increase the actual charging current of the system according to the preset step value.

[0042] In an embodiment of the present invention, when over-power charging does not exist in all the battery packs, the actual charging current of the current system can be obtained. The actual charging current of the system is the sum of the actual charging currents of each battery pack. Then, the actual charging current of the system is increased according to the step value to obtain a simulated current. It can be understood that the simulated current means that the system does not substantially increase the charging current, but simulates the situation where each battery pack will have over-power charging after increasing by one step value. The estimated actual current is the charging current simulated by each battery pack after the actual charging current of the system is increased by one step value. Then, it is confirmed whether over-power charging exists in the battery pack according to the requested charging current and the estimated actual current.

[0043] For example, if the requested charging current of the host pack is 40A, the actual charging current is 30A, the requested charging current of the first power-up pack is 20A, the actual charging current is 18A, the requested current of the second power-up pack is 15A, and the actual charging current is 12A, and the step value is 5A. When over-power charging does not exist in all the battery packs, calculate the sum of the actual charging currents of all the battery packs to obtain the actual charging current of the system, that is, 30A + 18A + 12A = 60A. The simulated current after increasing by one step value is 65A. Then, the 65A charging current is distributed to the host pack, the first power-up pack, and the second power-up pack according to a certain ratio to obtain the estimated actual current of each battery pack. For example, it can be distributed according to the ratio of the actual charging current. Then, the ratio of the actual charging currents of the host pack, the first power-up pack, and the second power-up pack is 5:3:2. Distribute 65A to the host pack, the first power-up pack, and the second power-up pack according to 5:3:2. Then, the estimated actual current of the host pack is 32.5A, the estimated actual current of the first power-up pack is 19.5A, and the estimated actual current of the second power-up pack is 13A, all of which do not exceed their respective requested charging currents. Then, the system can increase the system charging current according to the step value.

[0044] See Figure 4 , in some embodiments, such as in this embodiment, step S143 may include steps S1431 - S1432.

[0045] S1431, obtain the actual charging current of each battery pack, and calculate the ratio between all the actual charging currents to obtain a current ratio;

[0046] S1432, obtain the simulated current, and distribute the simulated current to each battery pack according to the current ratio to obtain the estimated actual current of each battery pack.

[0047] In the embodiments of the present invention, when distributing the simulated current, it can be distributed according to the ratio of the actual charging current. Then, the actual charging current of each battery pack can be obtained and the ratio between them can be calculated to obtain a current ratio, and then the simulated current can be distributed to each battery pack according to the current ratio. As can be seen from the foregoing, if the requested charging current of the host pack is 40A and the actual charging current is 30A, the requested charging current of the first power - adding pack is 20A and the actual charging current is 18A, and the requested current of the second power - adding pack is 15A and the actual charging current is 12A, then the current ratio is 5:3:2.

[0048] See Figure 5 , in some embodiments, such as in this embodiment, the multi - battery - pack charging method may further include step S146.

[0049] S146, if any one of all the battery packs has over - power charging, do not adjust the system charging current.

[0050] In the embodiments of the present invention, if during the simulation process, any one of the battery packs has over - power charging, do not adjust the system charging current.

[0051] See Figure 6 , in some embodiments, such as in this embodiment, the multi - battery - pack charging method may further include steps S150 - S160.

[0052] S150, obtain the current actual charging current of the current system, and confirm whether the current actual charging current of the current system is greater than the current upper limit value of the multi - battery - pack system;

[0053] S160, if the current actual charging current of the current system is greater than or equal to the current upper limit value of the multi - battery - pack system, set the current upper limit value of the multi - battery - pack system as the system charging current of the multi - battery - pack system.

[0054] In an embodiment of the present invention, when the actual charging current of the system is greater than the current upper limit value, the current upper limit value can be used as the system charging current. The current upper limit value is determined by the charge and discharge device. That is, the maximum actual charging current of the system does not exceed the upper limit allowed by the charge and discharge device. When it exceeds, the maximum current value of the charge and discharge device is used as the actual charging current for charging.

[0055] See Figure 7 , in some embodiments, such as in this embodiment, the multi-battery pack charging method may further include step S170.

[0056] S170, if the current actual charging current of the system is less than the current upper limit value of the multi-battery pack system, return to the step of obtaining the requested charging current and the actual charging current of each battery pack in the multi-battery pack system in real time.

[0057] In an embodiment of the present invention, if the actual charging current of the system is not greater than the current upper limit value, step S110 can be returned to continue to confirm whether the system charging current can be increased.

[0058] See Figure 8 , in some embodiments, such as in this embodiment, step S120 may include steps S121 - S122.

[0059] S121, confirm the magnitude between the requested charging current and the actual charging current;

[0060] S122, if the requested charging current is greater than the actual charging current, confirm that there is no over-power charging;

[0061] S123, if the requested charging current is less than or equal to the actual charging current, confirm that there is over-power charging.

[0062] In an embodiment of the present invention, over-power charging means that the actual charging current is greater than or equal to the requested charging current. After obtaining the actual charging current and the requested charging current, the magnitude between the actual charging current and the requested charging current can be compared. When the actual charging current is greater than or equal to the requested charging current, it indicates that there is over-power charging. When the actual charging current is less than the requested charging current, it indicates that the battery pack is normal.

[0063] The present invention also provides a multi-battery pack system, and the multi-battery pack system is configured with the charging method of the multi-battery pack described in any one of the above embodiments.

[0064] The charging method and system for multiple battery packs disclosed by the present invention can obtain the requested charging current and the actual charging current of each battery pack, and confirm whether there is over-power charging for each battery pack according to the requested charging current and the actual charging current. When there is over-power charging for a battery pack, the system charging current is reduced to prevent the battery pack from being in the over-power charging state for a long time, which can extend the service life of the battery pack.

[0065] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for charging multiple battery packs, characterized in that: Applied to a multi-battery pack system, the method comprises: Acquire the requested charging current and the actual charging current of each battery pack in the multi-battery pack system in real time; Determining whether the battery pack is overcharged according to the requested charging current and the actual charging current; If any one of the battery packs is over-charged, the system charging current of the multi-battery pack system is reduced according to a preset step value.

2. The method according to claim 1, characterized in that The method further comprises: Obtaining a preset charging current of the multi-battery pack system; The preset charging current is used as the system charging current to configure a charging current for each battery pack.

3. The method according to claim 1, characterized in that The method further comprises: If all the battery packs do not have the over-power charging, then obtaining the current actual charging current of the system; Simulating increasing the actual charging current of the system according to a preset step value to obtain a simulated current; configuring a charging current for each of the battery packs according to the simulated current to obtain an estimated actual current for each of the battery packs; Determining whether the battery pack is overcharged according to the requested charging current and the estimated actual current; If all the battery packs are not over-power charged, the actual charging current of the system is increased according to the preset step value.

4. The method according to claim 3, characterized in that The step of configuring a charging current for each battery pack according to the simulated current to obtain an estimated actual current of each battery pack comprises: Obtaining an actual charging current of each of the battery packs, and calculating a ratio between all of the actual charging currents to obtain a current ratio; The simulated current is acquired, and the simulated current is distributed to each of the battery packs according to the current ratio to obtain the estimated actual current of each of the battery packs.

5. The method according to claim 3, characterized in that After the step of confirming whether the battery pack is overcharged according to the requested charging current and the estimated actual current, the method further includes: If any one of the battery packs is over-charged, the system charging current will not be adjusted.

6. The method according to claim 1, characterized in that The method further comprises: Obtaining the actual charging current of the current system, and confirming whether the actual charging current of the current system is greater than the current upper limit value of the multi-battery pack system; If the current actual charging current of the system is greater than or equal to the current upper limit value of the multi-battery pack system, the current upper limit value of the multi-battery pack system is set as the system charging current of the multi-battery pack system.

7. The method according to claim 6, characterized in that After the step of confirming whether the actual charging current of the current system is greater than the current upper limit value of the multi-battery pack system, the method further includes: If the actual charging current of the current system is less than the current upper limit value of the multi-battery pack system, then return to the step of obtaining the requested charging current and the actual charging current of each battery pack in the multi-battery pack system in real time.

8. The method according to claim 1, characterized in that The step of confirming whether the battery pack is overcharged according to the requested charging current and the actual charging current includes: confirming a magnitude relationship between the requested charging current and the actual charging current; If the requested charging current is greater than the actual charging current, it is determined that there is no over-power charging.

9. The method according to claim 8, characterized in that After the step of confirming the magnitude relationship between the requested charging current and the actual charging current, the method further includes: If the requested charging current is less than or equal to the actual charging current, it is determined that overpower charging exists.

10. A multi-battery system, characterized in that: A method for charging a multi-battery pack configured as described in any one of claims 1-9.

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