Series-parallel connection switching automobile emergency starting power supply circuit

Abstract

The utility model provides an automobile emergency starting power supply circuit capable of switching between series connection and parallel connection, a first battery cell group and a second battery cell group are respectively provided with four battery cells, the battery cells are sequentially connected in series in the two battery cell groups, the negative electrode of the battery cell 1 is the negative electrode B1-of the first battery cell group, the positive electrode of the battery cell 4 is the positive electrode B1 + of the first battery cell group, and the negative electrode of the battery cell 2 is the negative electrode B1-of the first battery cell group. The negative electrode of the battery cell 5 is the negative electrode B2-of the second battery cell group, the positive electrode of the battery cell 8 is the positive electrode B2 + of the second battery cell group, and the negative electrode B1-of the first battery cell group and the positive electrode B2 + of the second battery cell group serve as clamp ends and are connected with the clamp negative electrode and the clamp positive electrode respectively; the three relays are connected into the circuit, the 12V power supply state and the 24V power supply state can be accurately and reasonably switched, meanwhile, the charging state is switched through the charging circuit and the relays, and compared with the prior art, the reliability, the use convenience of a user and the like are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of automotive emergency starting power supplies, and particularly relates to a circuit of an automotive emergency starting power supply with series-parallel switching. Background Art

[0002] Under normal circumstances, the starting of a vehicle can be completed by using the electrical energy stored in the vehicle battery itself. However, if the vehicle battery is aged or the energy storage is insufficient due to other reasons, an additional starting power supply is required to start the vehicle, especially in fuel vehicles. An automotive emergency starting power supply is a product designed specifically for a discharged vehicle battery. It utilizes the characteristic of a large instantaneous discharge current of a lithium battery to provide instantaneous energy for vehicle starting. Usually, the instantaneous current during the starting of a household vehicle (12V battery) can reach more than 400A, and the starting current of commercial vehicles such as trucks and buses (24V batteries) can reach more than 600A. Since users such as repair shops and truck drivers have the starting requirements for both 12V and 24V vehicles, and traditional starting power supplies cannot be used for vehicles with mismatched voltages of the vehicle's built-in batteries, sometimes it is necessary to find a matching starting power supply separately, which brings inconvenience.

[0003] There are also automotive emergency starting power supplies that can be used for both 12V and 24V in the prior art. Most of these products have the following defects: for the starting of 12V and 24V vehicles, the position of the terminal needs to be changed, the operation process is complex, and the user experience is poor; when starting a 12V vehicle, only cells No. 1-4 are used, and cells No. 5-7 are not used, resulting in insufficient starting ability; after starting a 12V vehicle and then starting a 24V vehicle, it will cause unbalanced discharge of the cells, and the first four cells are prone to over-discharge, and in severe cases, the cells will be damaged; two chargers are required for charging, which is costly and the operation is complex; the clips are directly connected to the battery and conduct immediately after being clipped, without an intelligent judgment function; if clipped in reverse, it will cause damage to the battery and the starting power supply; if the clips are short-circuited, it will cause damage to the starting power supply; if starting for a long time, it will cause damage to the cells of the starting power supply due to over-discharge. It should be noted that being clipped in reverse means that the positive clip is clipped to the negative terminal of the battery, and the negative clip is clipped to the positive terminal of the battery; short-circuiting means that the positive and negative clips are clipped together. Summary of the Utility Model

[0004] The purpose of the utility model is to provide an improved solution for an automotive emergency starting power supply in view of the deficiencies in the above-mentioned background art.

[0005] To achieve the above object, the present utility model provides an automotive emergency starting power supply circuit with series-parallel switching, including a first battery cell group and a second battery cell group. Both the first battery cell group and the second battery cell group are provided with four battery cells. Inside the two battery cell groups, the battery cells are connected in series in sequence. The negative electrode of battery cell 1 is the negative electrode B1- of the first battery cell group, the positive electrode of battery cell 4 is the positive electrode B1+ of the first battery cell group, the negative electrode of battery cell 5 is the negative electrode B2- of the second battery cell group, and the positive electrode of battery cell 8 is the positive electrode B2+ of the second battery cell group. The negative electrode B1- of the first battery cell group and the positive electrode B2+ of the second battery cell group are used as the clip ends and are respectively connected to the clip negative electrode and the clip positive electrode;

[0006] Three relays are connected in the circuit. Relay S1 is arranged on the connection line between the positive electrode B1+ of the first battery cell group and the negative electrode B2- of the second battery cell group. Relay S2 is arranged on the connection line between the negative electrode B1- of the first battery cell group and the negative electrode B2- of the second battery cell group. Relay S3 is arranged on the connection line between the positive electrode B1+ of the first battery cell group and the positive electrode B2+ of the second battery cell group.

[0007] Further, the rated current of the relay S1 is less than the rated currents of the relay S2 and the relay S3.

[0008] Further, it further includes a charging circuit. The charging circuit is provided with five ports for connection with a charger. Port 1 is connected to the negative electrode of battery cell 1 through balance line 1. Port 2 is connected to the positive electrode of battery cell 1, the negative electrode of battery cell 2, the positive electrode of battery cell 5, and the negative electrode of battery cell 6 through balance line 2. Port 3 is connected to the positive electrode of battery cell 2, the negative electrode of battery cell 3, the positive electrode of battery cell 6, and the negative electrode of battery cell 7 through balance line 3. Port 4 is connected to the positive electrode of battery cell 3, the negative electrode of battery cell 4, the positive electrode of battery cell 7, and the negative electrode of battery cell 8 through balance line 4. Port 5 is connected to battery cell 4 through balance line 5; Relays S6, S5, and S4 are respectively arranged on balance line 2, balance line 3, and balance line 4.

[0009] Further, the relay S6 is located on the connection line between the positive electrode of battery cell 1 and the negative electrode of battery cell 2, and the positive electrode of battery cell 5 and the negative electrode of battery cell 6. The relay S5 is located on the connection line between the positive electrode of battery cell 2 and the negative electrode of battery cell 3, and the positive electrode of battery cell 6 and the negative electrode of battery cell 7. The relay S4 is located on the connection line between the positive electrode of battery cell 3 and the negative electrode of battery cell 4, and the positive electrode of battery cell 7 and the negative electrode of battery cell 8.

[0010] The above scheme of the present utility model has the following beneficial effects:

[0011] The automotive emergency starting power supply circuit with series-parallel switching provided by the present utility model can accurately and reasonably switch among the 12V power supply state, 24V power supply state, and charging state, thereby being able to adapt to the emergency starting of two different voltage vehicles. Under series-parallel switching, it solves the problems of insufficient utilization of battery cells and unbalanced battery cells when starting a 12V vehicle; at the same time, it solves the problem of manually switching the clip terminals when starting a 12V / 24V dual-purpose starting power supply, and can achieve electronic switching, making it more convenient to use; it realizes parallel charging of battery cells, and only one charger is required to achieve charging, reducing the product cost and facilitating user use; in addition, it should be noted that through series-parallel switching, functions such as intelligent voltage detection, reverse connection prevention, and current backflow prevention can be further developed in the future;

[0012] Other beneficial effects of the present utility model will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the present utility model;

[0014] Figure 2 is a schematic diagram of the charging circuit of the present utility model (before improvement);

[0015] Figure 3 is a schematic diagram of the charging circuit of the present utility model (after improvement). SPECIFIC IMPLEMENTATION MODE

[0016] The following specific examples illustrate the implementation manners of the present disclosure. Those skilled in the art can easily understand other advantages and effects of the present disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. The present disclosure can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts belong to the scope of protection of the present disclosure.

[0017] It should be noted that the following describes various aspects of embodiments within the scope of the appended claims. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is illustrative only. Based on this disclosure, those skilled in the art should understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement a device and / or practice a method. Additionally, this device can be implemented and this method can be practiced using other structures and / or functionality in addition to one or more of the aspects described herein.

[0018] It should also be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present disclosure schematically. Only the components related to the present disclosure are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex. Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the aspects described herein can be practiced without these specific details.

[0019] As Figure 1 shown, an embodiment of the present utility model provides an automotive emergency starting power supply circuit with series-parallel switching, using lithium iron phosphate battery cells as the energy unit of the automotive emergency starting power supply. Since the maximum voltage of a lithium iron phosphate battery cell is 3.6V, when starting a 12V vehicle, four series-connected battery cells are used, and the maximum voltage is 14.4V; when starting a 24V vehicle, eight series-connected battery cells are used, and the maximum voltage is 28.8V. In this embodiment, the battery cells are divided into two groups. The first battery cell group is numbered battery cells 1, 2, 3, 4, and the second battery cell group is numbered battery cells 5, 6, 7, 8.

[0020] Among them, the negative electrode of battery cell 1 is the negative electrode B1- of the first battery cell group, the positive electrode of battery cell 4 is the positive electrode B1+ of the first battery cell group, the negative electrode of battery cell 5 is the negative electrode B2- of the second battery cell group, and the positive electrode of battery cell 8 is the positive electrode B2+ of the second battery cell group. Inside the two battery cell groups, the battery cells are connected in series in sequence. The negative electrode B1- of the first battery cell group and the positive electrode B2+ of the second battery cell group are used as the clip ends and are connected to the clip negative electrode and the clip positive electrode respectively.

[0021] Meanwhile, three relays S1, S2, and S3 are connected in the circuit to achieve series-parallel switching. Among them, relay S1 is set on the connection line between the positive electrode B1+ of the first battery cell group and the negative electrode B2- of the second battery cell group, relay S2 is set on the connection line between the negative electrode B1- of the first battery cell group and the negative electrode B2- of the second battery cell group, and relay S3 is set on the connection line between the positive electrode B1+ of the first battery cell group and the positive electrode B2+ of the second battery cell group.

[0022] In the 24V mode, relay S1 is closed, and S2 and S3 are open. At this time, the positive electrode B1+ of the first battery cell group is connected to the negative electrode B2- of the second battery cell group, and the first battery cell group and the second battery cell group are in series. The voltage at the clip end is the series voltage of the two battery cell groups; in the 12V mode, relay S1 is open, and S2 and S3 are closed. At this time, the negative electrode B1- of the first battery cell group is connected to the negative electrode B2- of the second battery cell group, and the positive electrode B1+ of the first battery cell group is connected to the positive electrode B2+ of the second battery cell group. The first battery cell group and the second battery cell group are in parallel, and the voltage at the clip end is the parallel voltage of the two battery cell groups.

[0023] Therefore, in the 24V mode, the current only passes through relay S1; in the 12V mode, the current passes through relays S2 and S3 at the same time. It can be understood that the current passing through relay S1 is larger, while the current passing through relays S2 and S3 is smaller. Therefore, relay S1 needs to select a specification with a larger rated current, and relays S2 and S3 can select specifications with a smaller rated current.

[0024] For the charging of the automotive emergency starting power supply, in order to optimize the charging operation process, a charger is used to charge the automotive emergency starting power supply. When charging, the two battery cell groups are connected in parallel, and then a charging circuit can be used to charge the two battery cell groups.

[0025] Among them, the charging circuit has five ports, which are respectively represented as ports 1, 2, 3, 4, and 5. Port 1 is connected to the negative electrodes of cell 1 and cell 5 through balance line 1, port 2 is connected to the positive electrode of cell 1, the negative electrode of cell 2, the positive electrode of cell 5, and the negative electrode of cell 6 through balance line 2, port 3 is connected to the positive electrode of cell 2, the negative electrode of cell 3, the positive electrode of cell 6, and the negative electrode of cell 7 through balance line 3, port 4 is connected to the positive electrode of cell 3, the negative electrode of cell 4, the positive electrode of cell 7, and the negative electrode of cell 8 through balance line 4, and port 5 is connected to the positive electrodes of cell 4 and cell 8 through balance line 5.

[0026] Such as Figure 2As shown in the figure, the charging circuit before optimization is analyzed. When the relay S1 is closed, the positive electrode of the battery cell 4 can be connected to the negative electrode of the battery cell 5 through the relay S1. The negative electrode balance line of the battery cell 5 is connected to the negative electrode balance line of the battery cell 1. At this time, it is equivalent to connecting the negative electrode of the battery cell 1 to the positive electrode of the battery cell 4, which will cause a short circuit inside the first battery cell group. By the same token, it can be known that when S1 is closed, the second battery cell group will also have an internal short circuit. Therefore, when the relay S1 is closed, the balance lines connected in parallel need to be disconnected.

[0027] Therefore, a relay can be added in the middle of the balance lines of the two groups of battery cells, and it is only closed during charging to make each battery cell of the two groups completely connected in parallel. Since when S2 and S3 are closed, it is equivalent to connecting the balance line 1 and the balance line 5 in parallel, only the balance lines 2, 3, and 4 need to be disconnected. In this embodiment, three relays S4, S5, and S6 are arranged in the middle of the balance lines 2, 3, and 4, and together with S2 and S3, they form a parallel charging circuit, as Figure 3 shown. Moreover, the relay S6 is located on the connection line between the positive electrode of the battery cell 1 and the negative electrode of the battery cell 2, and the positive electrode of the battery cell 5 and the negative electrode of the battery cell 6. The relay S5 is located on the connection line between the positive electrode of the battery cell 2 and the negative electrode of the battery cell 3, and the positive electrode of the battery cell 6 and the negative electrode of the battery cell 7. The relay S4 is located on the connection line between the positive electrode of the battery cell 3 and the negative electrode of the battery cell 4, and the positive electrode of the battery cell 7 and the negative electrode of the battery cell 8.

[0028] When the charger is connected, the relays S2, S3, S4, S5, and S6 are closed simultaneously, and the relay S1 is disconnected. At this time, the battery cells of the first battery cell group and the second battery cell group are connected in parallel one by one. Among them, the battery cell 1 is connected in parallel with the battery cell 5, the battery cell 2 is connected in parallel with the battery cell 6, the battery cell 3 is connected in parallel with the battery cell 7, and the battery cell 4 is connected in parallel with the battery cell 8, and the two groups of battery cells can be charged simultaneously. When used for starting a 24V vehicle, close S1, and the rest of the relays are all disconnected, which will not cause an internal short circuit.

[0029] In short, by adopting the series-parallel switching automotive emergency starting power supply circuit provided by this embodiment, it can accurately and reasonably switch the 12V power supply state, 24V power supply state, and charging state, so as to be able to adapt to the emergency starting of two different voltage vehicles. Under the series-parallel switching, the problems of insufficient utilization of battery cells and imbalance of battery cells when starting a 12V vehicle are solved; at the same time, the problem of manually switching the clip terminals when starting a 12V / 24V dual-purpose starting power supply is solved, and electronic switching can be realized, making it more convenient to use; parallel charging of battery cells is realized, and only one charger is needed to achieve charging, reducing the product cost and facilitating user use; in addition, it should be noted that through series-parallel switching, functions such as intelligent voltage detection, reverse connection prevention, and current backflow prevention can be further developed in the future.

[0030] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, 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, it should be considered as the scope recorded in this specification.

[0031] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation to the scope of the application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A series-parallel switching automobile emergency starting power supply circuit, characterized in that: It includes a first battery cell group and a second battery cell group, each of which is provided with four battery cells. Inside the two battery cell groups, the battery cells are sequentially connected in series, the negative electrode of battery cell 1 is the negative electrode B1- of the first battery cell group, the positive electrode of battery cell 4 is the positive electrode B1+ of the first battery cell group, the negative electrode of battery cell 5 is the negative electrode B2- of the second battery cell group, and the positive electrode of battery cell 8 is the positive electrode B2+ of the second battery cell group. The negative electrode B1- of the first battery cell group and the positive electrode B2+ of the second battery cell group are connected to the negative electrode of the clip and the positive electrode of the clip as clip ends, respectively; Three relays are connected in the circuit, relay S1 is set on the line between the positive pole B1+ of the first battery cell group and the negative pole B2- of the second battery cell group, relay S2 is set on the line between the negative pole B1- of the first battery cell group and the negative pole B2- of the second battery cell group, and relay S3 is set on the line between the positive pole B1+ of the first battery cell group and the positive pole B2+ of the second battery cell group.

2. The series-parallel switching automobile emergency starting power supply circuit according to claim 1 is characterized in that: The rated current of the relay S1 is smaller than the rated currents of the relay S2 and the relay S3.

3. The series-parallel switching automobile emergency starting power supply circuit according to claim 1 is characterized in that: It also includes a charging circuit, which is provided with five ports connected to the charger, port 1 is connected to the negative electrode of battery cell 1 through balance line 1, port 2 is connected to the positive electrode of battery cell 1, the negative electrode of battery cell 2, the positive electrode of battery cell 5, and the negative electrode of battery cell 6 through balance line 2, port 3 is connected to the positive electrode of battery cell 2, the negative electrode of battery cell 3, the positive electrode of battery cell 6, and the negative electrode of battery cell 7 through balance line 3, port 4 is connected to the positive electrode of battery cell 3, the negative electrode of battery cell 4, the positive electrode of battery cell 7, and the negative electrode of battery cell 8 through balance line 4, and port 5 is connected to battery cell 4 through balance line 5; balance line 2, balance line 3, and balance line 4 are respectively provided with relay S6, relay S5, and relay S4.

4. The series-parallel switching automobile emergency starting power supply circuit according to claim 3 is characterized in that: The relay S6 is located on the positive pole of battery cell 1 and the negative pole of battery cell 2, and on the line connecting the positive pole of battery cell 5 and the negative pole of battery cell 6. The relay S5 is located on the positive pole of battery cell 2 and the negative pole of battery cell 3, and on the line connecting the positive pole of battery cell 6 and the negative pole of battery cell 7. The relay S4 is located on the positive pole of battery cell 3 and the negative pole of battery cell 4, and on the line connecting the positive pole of battery cell 7 and the negative pole of battery cell 8.

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