Battery pack equalization system and method

Abstract

The invention discloses a battery pack balancing system and method, and the system comprises a battery pack module which comprises a main battery pack and an auxiliary battery pack, and the main battery pack and the auxiliary battery pack are connected in series; the charging module is electrically connected with the battery pack module, and the charging module is used for charging the main battery pack and the auxiliary battery pack; and the voltage conversion module is electrically connected with the charging module and the main battery pack, and the voltage conversion module is used for charging the main battery pack. According to the invention, the voltage conversion module is connected with the charging module and the main battery pack, the main battery pack is charged, the equalization of the main battery pack and the auxiliary battery pack is realized, and the equalization of the series battery system can be conveniently and quickly realized under the condition that the actual use is not influenced.

Description

Technical Field

[0001] The present invention belongs to the field of battery technology, and specifically relates to a battery pack balancing system and method. Background Art

[0002] Currently, in the field of battery technology, there are cases where a battery pack is used that can supply current at a desired voltage to a load side by connecting independent unit batteries in series. Of such battery packs, a type that can be repeatedly used by using rechargeable unit batteries and recharging according to the decrease in the charge amount is often used.

[0003] The battery pack has a tendency to have non-uniform charging states of the main battery pack and the secondary battery pack when repeatedly charged and discharged. In the prior art, the capacity of the main battery pack and the secondary battery pack is balanced by using a secondary motor to supplement the power of the main battery pack. However, frequent use of the secondary motor will cause the capacity gap between the main battery pack and the secondary battery pack to become larger and larger, thereby affecting the performance of the entire battery system.

[0004] Based on this, the art urgently needs a battery pack balancing system and method to solve the above technical problems. Summary of the invention

[0005] The present invention provides a battery pack balancing system, comprising:

[0006] A battery pack module, the battery pack module comprising a main battery pack and a secondary battery pack, the main battery pack and the secondary battery pack being connected in series;

[0007] A charging module, the charging module is electrically connected to the battery pack module, and the charging module is used to charge the main battery pack and the auxiliary battery pack;

[0008] A voltage conversion module is provided, wherein the voltage conversion module is electrically connected to the charging module and the main battery pack. The voltage conversion module receives the voltage output by the charging module and steps down the voltage before outputting it to the main battery pack to recharge the main battery pack.

[0009] Furthermore, it also includes a switch circuit module, the switch circuit module includes a first relay and a second relay;

[0010] The first relay electrically connects the charging module and the voltage conversion module, and the first relay is used to control the connection and disconnection between the voltage conversion module and the charging module.

[0011] The second relay electrically connects the voltage conversion module and the main battery pack, and the second relay is used to control the connection and disconnection between the voltage conversion module and the main battery pack.

[0012] Furthermore, it also includes a battery pack balancing control module, which is connected to the main battery pack and the auxiliary battery pack respectively, and is used to collect the voltage of the main battery pack and the voltage of the auxiliary battery pack respectively.

[0013] Further, the battery pack balancing control module is connected to the switch circuit module, and the battery pack balancing control module is used to control the closing and opening of the first relay and the second relay;

[0014] When the voltage of the main battery pack collected by the battery pack balancing control module is lower than the voltage of the auxiliary battery pack, the battery pack balancing control module controls the first relay and the second relay to close;

[0015] When the voltage of the main battery pack collected by the battery pack balancing control module is equal to or greater than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to be disconnected.

[0016] Further, the battery pack balancing control module is electrically connected to the charging module, and the battery pack balancing control module is electrically used to detect the charging signal of the charging module;

[0017] When the battery pack balancing control module detects that the charging signal of the charging module is disconnected, the battery pack balancing control module controls the first relay and the second relay to be disconnected.

[0018] Furthermore, the voltage conversion module is a DCDC converter.

[0019] Furthermore, the main battery pack includes a plurality of modular batteries connected in series, each of which can be replaced, and the secondary battery pack includes a plurality of modular batteries connected in series, each of which can be replaced.

[0020] The present invention also provides a battery pack balancing method, comprising the following steps:

[0021] Determining that the battery pack module is in a charging state;

[0022] The battery pack balancing control module collects the voltage of the main battery pack and the voltage of the auxiliary battery pack, and determines whether the voltage of the main battery pack is less than the voltage of the auxiliary battery pack;

[0023] If yes, the battery pack balancing control module controls the first relay and the second relay to close; if no, the battery pack balancing control module controls the first relay and the second relay to open.

[0024] Furthermore, if yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes:

[0025] The battery pack balancing control module detects whether the main battery pack and the auxiliary battery pack are fully charged;

[0026] If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

[0027] Furthermore, if yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes:

[0028] The battery pack balancing control module detects whether the charging signal of the charging module is disconnected;

[0029] If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

[0030] Compared with the prior art, the present invention provides a battery pack balancing system and method. The present invention sets a voltage conversion module to connect the charging module and the main battery pack, so that the charging module can supplement the power of the main battery pack through the voltage conversion module, thereby achieving capacity balance between the main battery pack and the auxiliary battery pack. It can quickly and conveniently achieve balancing of the series battery system without affecting actual use. At the same time, it also avoids the problem of using an auxiliary motor, which causes the performance of the entire battery system to decline. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only part of the embodiments of the present invention, rather than all of the embodiments. For ordinary technicians in this field, without paying creative work, other drawings obtained based on these drawings all fall within the scope of protection of this application.

[0032] Figure 1 is a schematic diagram of a circuit module of a battery pack balancing system provided by an embodiment of the present invention;

[0033] Figure 2 is a circuit schematic diagram of a battery pack balancing system provided by an embodiment of the present invention;

[0034] Figure 3 It is a flow chart of a battery pack balancing method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] In order to make the description of the disclosed content more detailed and complete, the following is an illustrative description of the implementation mode and specific examples of the present invention; however, this is not the only form of implementing or applying the specific embodiments of the present invention. The implementation mode covers the features of multiple specific embodiments and the method steps and their sequence for constructing and operating these specific embodiments. However, other specific embodiments can also be used to achieve the same or equal functions and step sequences. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0038] In the description of the embodiments of the present invention, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two, and other quantifiers are similar. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention, and the embodiments of the present application and the features in the embodiments may be combined with each other without conflict.

[0039] Please refer to Figure 1-Figure 3 , which is used to solve the problem of how to achieve capacity balance between the main battery pack and the auxiliary battery pack while avoiding an increasing capacity gap between the main battery pack and the auxiliary battery pack.

[0040] For details, please refer to Figure 1A circuit module schematic diagram of a battery pack balancing system provided in an embodiment of the present invention. The embodiment of the present invention provides a battery pack balancing system, including: a battery pack module, a charging module and a voltage conversion module. By setting the voltage conversion module to connect the charging module and the main battery pack, the charging module replenishes the main battery pack through the voltage conversion module, thereby achieving capacity balance between the main battery pack and the auxiliary battery pack, and can conveniently and quickly achieve balancing of the series battery system without affecting actual use.

[0041] Specifically, the battery pack module includes a main battery pack and a secondary battery pack, the main battery pack and the secondary battery pack are connected in series, and the main battery pack and the secondary battery pack are connected together in series so that their total voltage is the sum of the voltages of each battery pack; the charging module is electrically connected to the battery pack module, and the charging module is electrically connected to the battery pack module, and can charge two battery packs at the same time. The charging module is used to charge the main battery pack and the secondary battery pack, and provide charging current to the main battery pack and the secondary battery pack to restore the energy of the battery; a voltage conversion module, the voltage conversion module is electrically connected to the charging module and the main battery pack, and the voltage conversion module The block receives the voltage output by the charging module and outputs it to the main battery pack after stepping down the voltage to replenish the main battery pack. The voltage conversion module is electrically connected to the charging module and the main battery pack, and can obtain energy from the charging module and transfer it to the main battery pack that needs to be replenished. The voltage conversion module can avoid overcharging or over-discharging of a battery pack by balancing the voltage of the main battery pack and the auxiliary battery pack, thereby extending the life of the entire battery system, avoiding the problem of performance degradation of the entire battery system caused by the use of an auxiliary motor, and ensuring voltage consistency between the main battery pack and the auxiliary battery pack connected in series, thereby improving the performance and life of the entire battery system.

[0042] Furthermore, it also includes a switching circuit module, which includes a first relay and a second relay; the first relay electrically connects the charging module and the voltage conversion module, and the first relay is used to control the connection and disconnection between the voltage conversion module and the charging module, and the second relay electrically connects the voltage conversion module and the main battery pack, and the second relay is used to control the connection and disconnection between the voltage conversion module and the main battery pack. By setting the switch circuit module to include a first relay and a second relay, the disconnection and connection of the circuit can be controlled by controlling the disconnection and closing of the first relay and the second relay; the first relay electrically connects the charging module and the voltage conversion module, and the first relay is used to control the connection and disconnection of the voltage conversion module and the charging module; the second relay electrically connects the voltage conversion module and the main battery pack, and the second relay is used to control the connection and disconnection of the voltage conversion module and the main battery pack; when the battery pack balancing system realizes balancing, the first relay is closed to connect the charging module with the voltage conversion module, and the second relay is closed to connect the voltage conversion module with the main battery pack; the balancing module obtains energy from the charging module and transfers this part of energy to the main battery pack to increase its voltage; when the voltage of the main battery pack reaches a predetermined value, the first relay is disconnected to cut off the connection between the charging module and the voltage conversion module, and the second relay is disconnected to cut off the connection between the voltage conversion module and the main battery pack, and the charging operation is stopped, thereby realizing the control of the battery pack balancing system and improving the overall performance and safety of the system.

[0043] For further information, see Figure 2 The battery pack balancing system further includes a battery pack balancing control module, which is connected to the main battery pack and the secondary battery pack, respectively, and is used to collect the voltage of the main battery pack and the voltage of the secondary battery pack, respectively. By setting the battery pack balancing control module to connect to the main battery pack, the voltage of the main battery pack can be collected in real time, and by setting the battery pack balancing control module to connect to the secondary battery pack, the voltage of the secondary battery pack can be collected in real time. According to the collected voltage data, the battery pack balancing control module can determine whether it is necessary to start the balancing operation to avoid overcharging or over-discharging of a battery pack, thereby extending the life of the entire battery system.

[0044] Further, the battery pack balancing control module is connected to the switch circuit module, and the battery pack balancing control module is used to control the closing and opening of the first relay and the second relay; when the voltage of the main battery pack collected by the battery pack balancing control module is less than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to close; when the voltage of the main battery pack collected by the battery pack balancing control module is equal to or greater than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to open. By setting the battery pack balancing control module to be connected to the switch circuit module, when the voltage of the main battery pack is less than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to close, so that the voltage conversion module can transfer the energy provided by the charging module to the main battery pack, thereby increasing the voltage of the main battery pack. When the voltage of the main battery pack is equal to or greater than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to open and stop the balancing operation. In this way, the voltage balancing of the battery pack is achieved, the voltage consistency between the battery packs is ensured, and the overall performance of the battery pack balancing system is improved.

[0045] Furthermore, the battery pack balancing control module is electrically connected to the charging module, and the battery pack balancing control module is electrically used to detect the charging signal of the charging module; when the battery pack balancing control module detects that the charging signal of the charging module is disconnected, the battery pack balancing control module controls the first relay and the second relay to disconnect. By setting the battery pack balancing control module to be electrically connected to the charging module, the battery pack balancing control module is electrically used to detect the charging signal of the charging module, and when it is detected that the charging signal of the charging module is disconnected, the battery pack balancing control module controls the first relay and the second relay to disconnect and stop the balancing operation. The balancing operation can be stopped in time when the charging signal is disconnected, thereby improving the safety performance of the system.

[0046] Furthermore, the voltage conversion module is a DCDC converter. The voltage conversion module converts the 58V DC voltage output by the charging module into a 28V DC voltage and transmits it to the main battery pack. By setting the voltage conversion module as a voltage converter, the charging process of the charging module can be optimized. During the charging process, the voltage converter can help distribute the charging current more evenly, ensuring that both the main battery pack and the auxiliary battery pack can be properly charged, avoiding the situation where some battery packs are charged while other battery packs are undercharged, simplifying the design of the battery pack balancing system, and not requiring complex external circuits to achieve the voltage balancing function, reducing the complexity and cost of the system.

[0047] Furthermore, the main battery pack includes a plurality of modular batteries connected in series, each of which can be replaced, and the secondary battery includes a plurality of modular batteries connected in series, each of which can be replaced. By setting the main battery pack to include a plurality of modular batteries connected in series, each of which can be replaced, and the secondary battery to include a plurality of modular batteries connected in series, each of which can be replaced, each modular battery can be replaced individually, which makes maintenance and upgrading more convenient. When the total capacity of the battery pack needs to be increased, more modular batteries only need to be added, which facilitates the expansion of the battery pack, is simple and efficient.

[0048] The present invention also provides a battery pack balancing method, comprising the following steps:

[0049] Determining that the battery pack module is in a charging state;

[0050] The battery pack balancing control module collects the voltage of the main battery pack and the voltage of the auxiliary battery pack, and determines whether the voltage of the main battery pack is less than the voltage of the auxiliary battery pack;

[0051] If yes, the battery pack balancing control module controls the first relay and the second relay to close; if no, the battery pack balancing control module controls the first relay and the second relay to open.

[0052] As an optional implementation, when actually judging whether the voltage of the main battery pack is less than the voltage of the secondary battery pack, the threshold of the voltage difference is adjusted. Specifically, the lowest threshold of the voltage difference is set to -0.24V to judge whether the voltage of the main battery pack is less than the voltage of the secondary battery pack -0.24V.

[0053] Furthermore, if yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes:

[0054] The battery pack balancing control module detects whether the main battery pack and the auxiliary battery pack are fully charged;

[0055] If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

[0056] Furthermore, if yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes:

[0057] The battery pack balancing control module detects whether the charging signal of the charging module is disconnected;

[0058] If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

[0059] Furthermore, if yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes:

[0060] Determine whether the voltage of the main battery pack is greater than the voltage of the auxiliary battery pack;

[0061] If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

[0062] As an optional implementation, when actually judging whether the voltage of the main battery pack is greater than the voltage of the secondary battery pack, the threshold of the voltage difference is adjusted. Specifically, the highest threshold of the voltage difference is set to -0.08V to judge whether the voltage of the main battery pack is greater than the voltage of the secondary battery pack -0.08V.

[0063] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The above embodiments only express the preferred implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A battery pack balancing system, characterized in that: include: A battery pack module, the battery pack module comprising a main battery pack and a secondary battery pack, the main battery pack and the secondary battery pack being connected in series; A charging module, the charging module is electrically connected to the battery pack module, and the charging module is used to charge the main battery pack and the auxiliary battery pack; A voltage conversion module is provided, wherein the voltage conversion module is electrically connected to the charging module and the main battery pack. The voltage conversion module receives the voltage output by the charging module and steps down the voltage before outputting it to the main battery pack to recharge the main battery pack.

2. The battery pack balancing system according to claim 1, characterized in that: Also included is a switch circuit module, the switch circuit module including a first relay and a second relay; The first relay electrically connects the charging module and the voltage conversion module, and the first relay is used to control the connection and disconnection between the voltage conversion module and the charging module. The second relay electrically connects the voltage conversion module and the main battery pack, and the second relay is used to control the connection and disconnection between the voltage conversion module and the main battery pack.

3. The battery pack balancing system according to claim 2, characterized in that: It also includes a battery pack balancing control module, which is connected to the main battery pack and the auxiliary battery pack respectively, and is used to collect the voltage of the main battery pack and the voltage of the auxiliary battery pack respectively.

4. The battery pack balancing system according to claim 3, characterized in that: The battery pack balancing control module is connected to the switch circuit module, and the battery pack balancing control module is used to control the closing and opening of the first relay and the second relay; When the voltage of the main battery pack collected by the battery pack balancing control module is lower than the voltage of the auxiliary battery pack, the battery pack balancing control module controls the first relay and the second relay to close; When the voltage of the main battery pack collected by the battery pack balancing control module is equal to or greater than the voltage of the secondary battery pack, the battery pack balancing control module controls the first relay and the second relay to be disconnected.

5. The battery pack balancing system according to claim 4, characterized in that: The battery pack balancing control module is electrically connected to the charging module, and the battery pack balancing control module is electrically used to detect the charging signal of the charging module; When the battery pack balancing control module detects that the charging signal of the charging module is disconnected, the battery pack balancing control module controls the first relay and the second relay to be disconnected.

6. The battery pack balancing system according to claim 1, characterized in that: The voltage conversion module is a DCDC converter.

7. The battery pack balancing system according to claim 1, characterized in that: The main battery pack includes a plurality of modular batteries connected in series, each of which can be replaced, and the secondary battery pack includes a plurality of modular batteries connected in series, each of which can be replaced.

8. A battery pack balancing method, characterized in that: The following steps are involved: Determining that the battery pack module is in a charging state; The battery pack balancing control module collects the voltage of the main battery pack and the voltage of the auxiliary battery pack, and determines whether the voltage of the main battery pack is less than the voltage of the auxiliary battery pack; If yes, the battery pack balancing control module controls the first relay and the second relay to close; if no, the battery pack balancing control module controls the first relay and the second relay to open.

9. The battery pack balancing method according to claim 8, characterized in that: If yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes: The battery pack balancing control module detects whether the main battery pack and the auxiliary battery pack are fully charged; If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

10. The battery pack balancing method according to claim 8, characterized in that: If yes, after the battery pack balancing control module controls the closing of the first relay and the second relay, the method further includes: The battery pack balancing control module detects whether the charging signal of the charging module is disconnected; If yes, the battery pack balancing control module controls the first relay and the second relay to be disconnected; if no, the battery pack balancing control module controls the first relay and the second relay to be closed.

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