Battery pack and battery pack structure for maintaining faults of single cells in battery pack

Abstract

The utility model relates to a battery pack and a battery pack structure for maintaining faults of single cells in the battery pack, and belongs to the technical field of batteries. Comprising a plurality of battery cells, part of fault battery cells exist in the plurality of battery cells, the fault battery cells are disconnected and conductively connected between two normal battery cells and / or between the normal battery cells and an output end point of the battery pack, and the two normal battery cells and / or the normal battery cells and the output end point are conductively connected through connecting pieces. According to the utility model, the conductive connecting piece is used for replacing the conductive connection part of the faulted battery cell, so that the battery pack or the battery pack with the faulted battery cell can still be used, and the situation that the whole battery pack or the whole battery pack cannot be used due to the fault of part of the battery cells, and the whole battery pack or the battery pack needs to be replaced is avoided; resource waste is further avoided, and economic loss is reduced.

Description

Technical Field

[0001] The utility model relates to a battery pack and a battery pack structure for repairing single cell failures in the battery pack, belonging to the technical field of batteries. Background Art

[0002] The battery pack (PACK battery pack or battery pack PACK or PACK) used in the power battery system of new energy electric vehicles is mainly composed of multiple battery cells, a sampling harness (sampling line), a collection unit CSC, an aluminum bar as a connector for conductive connection, and a box structure component.

[0003] Among them, the battery cell (single cell or single cell or battery cell) is used as the power source of the power battery system. The battery cells are connected in series or in parallel through aluminum bars or copper bars as conductive media to form a high-voltage power supply system for the battery pack. The battery PACK grouping technology industry mostly adopts CTP (module-free battery technology or module-omitted battery technology or module-reduced battery technology, Cell to Pack) high integration and adhesive fixing solutions. The battery cell is directly fixed to the box body through structural adhesive bonding, and the volume energy density and mass energy density of the battery are improved by weakening the module or without the module. The sampling line completes the electrical signal connection between the battery cell, temperature probe and acquisition unit; the acquisition unit CSC collects and processes electrical signals and reports the basic information of the voltage and temperature of each cell in the battery pack. Among them, copper bars can also be used as connectors for conductive connections.

[0004] In order to solve the problem of abnormal battery cells that cannot be used, the industry usually removes the abnormal battery cells from the battery pack and replaces them with new ones of the same model. However, due to the gluing process used in CTP battery packs, the aluminum bars of the battery cells need to be removed, the structural glue between the battery cells and the bottom of the box needs to be removed, and the sampling line needs to be removed. After replacement, the battery cells need to be fixed and the high-voltage connection needs to be re-established. This has problems such as maintenance safety, damage to normal batteries during the maintenance process, and reduced mechanical performance after maintenance. In other words, it is difficult to replace the battery cells or the conditions for replacement are not met.

[0005] The battery pack needs to be replaced because of a single abnormal cell and is difficult to repair. The replaced battery pack cannot be reused and needs to be scrapped. Due to the difficulty or impossibility of repair, battery manufacturers often directly replace the battery pack with a new one, and the replaced battery pack cannot be reused, resulting in economic losses and waste of resources.

[0006] Similarly, with regard to the problem of battery cells being unable to be used due to abnormalities, there are also issues such as maintenance safety issues caused by the bonding process, damage to normal cells during the maintenance process, and reduced mechanical properties after maintenance. In other words, it is difficult to replace the battery cells or the conditions for replacement are not met. Utility Model Content

[0007] The utility model aims to provide a battery pack to solve the problem that the existing battery pack has abnormal battery cells and is difficult to repair, resulting in the need to replace the entire battery pack; and also provides a battery pack structure for repairing single cell failures in the battery pack to solve the problem that the existing battery pack has abnormal battery cells and is difficult to repair, resulting in the need to replace the entire battery pack.

[0008] To achieve the above purpose, the solution of the utility model includes:

[0009] A battery pack of the utility model comprises a plurality of battery cells, some of which are faulty battery cells, the faulty battery cells disconnect the conductive connection between two normal battery cells and / or between a normal battery cell and an output terminal of the battery pack, and the two normal battery cells and / or between a normal battery cell and an output terminal are conductively connected via a connector.

[0010] Furthermore, the connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar.

[0011] Furthermore, adjacent battery cells have poles of different names arranged adjacent to each other; the connector includes an intermediate connecting portion, and end connecting portions arranged at both ends of the intermediate connecting portion respectively face the positive electrode of the normal battery cell and the negative electrode of another normal battery cell and are conductively connected thereto and / or respectively face the poles and output terminals of the normal battery cell that are conductively disconnected from the faulty battery cell and are conductively connected thereto, so as to achieve conductive connection between two normal battery cells and / or conductive connection between the normal battery cell and the output terminal through the conductive connection between the intermediate connecting portion and the end connecting portion.

[0012] Furthermore, an insulating layer is provided on the outer surface of the intermediate connecting portion.

[0013] The utility model discloses a battery pack structure for repairing single cell failure in a battery pack, comprising a plurality of cells, some of which are faulty cells, the faulty cells disconnecting the conductive connection between two normal cells and / or between a normal cell and an output terminal of the battery pack, and the two normal cells and / or between a normal cell and the output terminal are conductively connected via a connector.

[0014] Furthermore, the connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar.

[0015] Furthermore, adjacent battery cells have poles of different names arranged adjacent to each other; the connector includes an intermediate connecting portion, and end connecting portions arranged at both ends of the intermediate connecting portion respectively face the positive electrode of the normal battery cell and the negative electrode of another normal battery cell and are conductively connected thereto and / or respectively face the poles and output terminals of the normal battery cell that are conductively disconnected from the faulty battery cell and are conductively connected thereto, so as to achieve conductive connection between two normal battery cells and / or conductive connection between the normal battery cell and the output terminal through the conductive connection between the intermediate connecting portion and the end connecting portion.

[0016] Furthermore, an insulating layer is provided on the outer surface of the intermediate connecting portion.

[0017] Furthermore, the battery cell is electrically connected to a collection unit via a sampling line, and the sampling lines at both ends of the faulty battery cell are electrically connected to a connector.

[0018] Beneficial effects of the utility model:

[0019] The utility model replaces the conductive connection part of the faulty battery cell with a conductive connector, so that the battery pack or battery pack with the faulty battery cell can still be used, avoiding the entire battery pack or battery pack being unusable due to the failure of some battery cells, which in turn causes the entire battery pack or battery pack to need to be replaced, further avoiding waste of resources and reducing economic losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the battery pack structure before rectification in the embodiment of the utility model;

[0021] Figure 2 This is a schematic diagram of the battery pack structure after rectification in the embodiment of the utility model;

[0022] Figure 3 It is a schematic diagram of the actual battery pack jumper rectification in the embodiment of the utility model.

[0023] Description of reference numerals:

[0024] 1. Disconnection point; 2. Aluminum bar (connector, high-voltage connector for connecting battery cells in series and parallel in the battery pack); 20. Middle connection part; 21. End connection part; 3. Sampling line; 4. Collection unit; 5. Faulty battery cell; 6. Normal battery cell. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0026] For ease of reading, specific words in this article are explained here as follows:

[0027] A battery pack (PACK) is generally composed of multiple battery groups, and also includes a battery management system (BMS). It is the final product provided by the battery factory to users. The components of the battery pack mainly include battery modules, mechanical systems, electrical systems, thermal management systems and BMS.

[0028] A battery pack is composed of multiple monomers, forming a single physical module to provide higher voltage and capacity.

[0029] Cell is the most basic element of battery packs and battery packs, and can generally provide a voltage between 3V and 4V.

[0030] The Battery Management System (BMS) is an important link between the on-board power battery and the electric vehicle. It is mainly composed of the Cell Monitor Unit (CMU) and the Battery Management Unit (BMU). Its main functions include: real-time monitoring of battery physical parameters, battery status estimation, online diagnosis and early warning, charging, discharging and pre-charging control, balancing management and thermal management, etc.

[0031] The sampling line is used to connect the single cell and the collection unit so that the collection unit can complete the sampling of basic signals such as battery cell voltage and temperature.

[0032] The single cell acquisition module, i.e. the acquisition unit (CSC, Cell Supercision Circuit), is a monitor installed on the battery cell. As the acquisition unit of the basic data of the battery management system, the monitor mainly completes the voltage and temperature acquisition of the power battery cell and the balanced control actuator. This product is generally installed in the battery pack, connected to the power battery cell through the sampling line, and the collected data is transmitted to the main control unit of the battery management system.

[0033] Aluminum bar / copper busbar is an aluminum bar or copper busbar, which serves as a high-voltage connector for connecting battery cells in series and parallel in a battery pack.

[0034] CTP (Cell to Pack) is a battery pack structure grouping technology with weakened modules or no modules.

[0035] In order to solve the problems in the background technology, the utility model replaces the original conductive connection function of the faulty battery cell with a conductive connector to repair the battery pack or battery pack, so that the battery pack or battery pack with the faulty battery cell can still be used, avoiding the battery pack or battery pack being unusable due to some faulty batteries, further avoiding wasting resources and reducing economic losses. Specifically, since there are multiple batteries in the battery pack, when an individual battery cell has an abnormality and needs to be replaced, the abnormal battery cell is separated from the high-voltage system and does not participate in the subsequent charging and discharging. It still remains in the battery pack but is no longer used, and the battery pack and other components can be used normally. Specifically, since there are multiple batteries in the battery pack, when an individual battery cell has an abnormality and needs to be replaced, the abnormal battery cell is separated from the high-voltage system and does not participate in the subsequent charging and discharging. It still remains in the battery pack but is no longer used, and the battery pack and other components can be used normally.

[0036] An embodiment of a battery pack structure for repairing a single cell failure in a battery pack:

[0037] A battery pack structure for repairing single cell failures in a battery pack, comprising a plurality of cells, some of which are faulty cells, that is, the total number of faulty cells is less than the total number of all cells in the battery pack, and the rest of the cells in the battery pack are normal cells except for the faulty cells. When the faulty cell disconnects the conductive connection between two normal cells, the two normal cells are conductively connected via a connector. When the faulty cell disconnects the conductive connection between a normal cell and an output terminal of the battery pack, the normal cell and the output terminal are conductively connected via a connector. When the faulty cell disconnects the conductive connection between two normal cells and another faulty cell disconnects the conductive connection between the normal cell and the output terminal of the battery pack, the two normal cells and the normal cell that was originally conductively connected to the output terminal via the faulty cell are conductively connected to the output terminal via the connector, respectively.

[0038] Disconnecting the conductive connection means that only the original conductive connection of the faulty battery is disconnected, and the rest remains unchanged.

[0039] The connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar, so as to improve the reliability of the connection between two normal battery cells and / or between a normal battery cell and an output terminal.

[0040] Among them, the poles of different names of adjacent battery cells are arranged adjacent to each other; the connector includes an intermediate connecting part, and the end connecting parts arranged at both ends of the intermediate connecting part are respectively oriented toward the positive electrode of the normal battery cell and the negative electrode of another normal battery cell and are conductively connected thereto and / or are respectively oriented toward the poles and output terminals that are conductively disconnected from the normal battery cell and the faulty battery cell and are conductively connected thereto, so as to realize the conductive connection of two normal battery cells and / or the conductive connection of the normal battery cell and the output terminal through the conductive connection between the intermediate connecting part and the end connecting part. At this time, the shape of the connector is similar to an "S" shape, and the connector saves materials while ensuring the normal use of the battery pack by replacing the original conductive connection of the faulty battery cell. Among them, an insulating layer is provided on the outer surface of the intermediate connecting part to ensure the safe use of the battery pack.

[0041] The battery cell is also electrically connected to a collection unit via a sampling line, and the sampling lines at both ends of the faulty battery cell are electrically connected to a connector to avoid invalid errors from being reported by the collection unit.

[0042] When there are some abnormal cells (faulty cells) in the battery pack, the repair steps are as follows:

[0043] ① Disconnect the high-voltage connection of the damaged single cell (faulty cell) from the original cell circuit; ② Customize the jumper cell aluminum bar according to the cell layout, and the aluminum bar can cross the faulty cell; ③ The previous battery pole and the next battery pole of the damaged battery (faulty cell) are connected with high voltage through the customized aluminum bar, and the two poles are poles of different names; ④ The sampling lines at both ends of the damaged battery are respectively connected to the customized aluminum bar or the sampling lines at both ends are first merged and then connected to the customized aluminum bar; ⑤ And upgrade the acquisition unit software to eliminate the faulty cell.

[0044] For example, there are 12 cells in the battery pack, which are defined as V1, V2, V3, ..., V11 and V12 in sequence. Figure 1 As shown; wherein, the positive electrode of the battery cell is represented by "+", and the negative electrode of the battery cell is represented by "-", that is, V12+ is the positive electrode of the twelfth battery cell; the 12 battery cells are conductively connected from V1+ to V2-, V2+ to V3-, ..., V10+ to V11-, and V11+ to V12-.

[0045] Assuming that V5 is any faulty battery cell 5, the utility model first disconnects the high-voltage connection of the damaged cell from the battery cell circuit, disconnecting the connection point 1 at Figure 1 Indicated by a cross in the middle; then according to the arrangement of battery cells, an aluminum bar 2 that can cross the faulty battery cell is used to conductively connect the front and rear batteries of the faulty battery cell 5, that is, the aluminum bar 2 is high-voltage connected to the battery cell V4+ in front of the faulty battery V5 and the battery cell V6- behind the faulty battery V5, and the sampling lines 3 at both ends of the damaged battery V5 are conductively connected to the aluminum bar 2. Specifically, the sampling lines 3 at both ends of the damaged battery V5 can be connected to the aluminum bar 2 respectively, or the sampling lines 3 at both ends of the damaged battery V5 can be merged first and then connected to the aluminum bar 2; finally, the collection unit 4 is upgraded to specifically eliminate the faulty battery V5, that is, the fault of the abnormal battery V5 after rectification is no longer reported.

[0046] The aluminum bar 2 is customized to bridge the normal battery cells according to the battery cell layout, that is, the aluminum bar can bridge the faulty battery cells to connect to the normal battery cells. More specifically, the aluminum bar 2 is shaped like an "S" shape, with a middle connection portion 20 and end connection portions 21 arranged at both ends of the middle connection portion 20, and the end connection portions 21 face the pole of the normal battery cell or the output terminal of the battery pack that is conductively connected to the original faulty battery cell. Figure 2 shown.

[0047] like Figure 3In the actual battery pack cross-connection rectification schematic diagram shown, the opposite poles of adjacent battery cells are arranged adjacent to each other, that is, the faulty battery cell 5 and the normal battery cells 6 on both sides are arranged adjacent to each other, and the positive pole of the faulty battery cell 5 and the negative pole of the normal battery cell 6 are arranged adjacent to each other, and the negative pole of the faulty battery cell 5 and the positive pole of the normal battery cell 6 are arranged adjacent to each other; the aluminum bar 2 as a connecting piece includes an intermediate connecting portion 20, and the end connecting portions 21 arranged at both ends of the intermediate connecting portion 20 are respectively facing the positive pole of the normal battery cell 6 and the negative pole of another normal battery cell 6, and the end connecting portions 21 at both ends are respectively conductively connected to the positive pole of the normal battery cell 6 and the negative pole of another normal battery cell 6; and the end connecting portions 21 arranged at both ends of the intermediate connecting portion 20 are respectively facing the poles and output terminals that disconnect the conductive connection with the faulty battery cell 5, and the end connecting portions 21 at both ends are respectively conductively connected to the aforementioned poles and output terminals, and the output terminal here can be the positive terminal point of the battery pack or the negative terminal point of the battery pack. The conductive connection between the middle connecting portion 20 and the end connecting portion 21 realizes the conductive connection between the two normal battery cells 6 and / or the conductive connection between the normal battery cell 6 and the output terminal.

[0048] The shape of the connector at this time is similar to an "S" shape. The connector ensures the normal use of the battery pack while saving materials by replacing the original conductive connection of the faulty battery cell. Among them, an insulating layer is provided on the outer surface of the middle connecting part to ensure the safe use of the battery pack.

[0049] The utility model belongs to the technical field of battery PACK for new energy electric vehicles, and aims to solve the problem of battery pack being scrapped due to abnormality of some battery cells.

[0050] The technical solution of the utility model is as follows:

[0051] Disconnect the aluminum bar / copper busbar and sampling line of the battery cell that needs to be replaced to disengage it from the battery pack circuit; customize the jumper aluminum bar according to the battery cell layout, jump over the faulty battery cell through the customized aluminum bar, connect the positive pole (+) of the previous battery (cell) of the damaged battery (faulty cell) with the negative pole (-) of the next battery (cell) through the aluminum bar at high voltage, and establish a new high-voltage connection; re-bond the sampling line, connect the sampling lines at both ends of the damaged battery to the aluminum bar respectively, or merge the sampling lines at both ends and then connect them to the aluminum bar; and upgrade the acquisition unit software to remove the faulty battery cell, and no longer report the abnormal battery cell fault after rectification.

[0052] Advantages of this program:

[0053] Solve the problem that some cells in the battery pack are abnormal and difficult or impossible to repair under the CTP (cell to pack, module-free battery technology or module-omitted battery technology or module-reduced battery technology) or CTC (cell to chassis, the battery cell is directly inherited from the vehicle chassis) process; avoid the mechanical performance of the battery pack being damaged after the cells are removed for repair; the repaired battery pack can be reused to reduce losses.

[0054] An embodiment of a battery pack:

[0055] A battery pack includes a plurality of battery cells, some of which are faulty, that is, the total number of the faulty battery cells is less than the total number of all the battery cells in the battery pack, and the rest of the battery pack except the faulty battery cells are normal battery cells. When the faulty battery cell disconnects the conductive connection between two normal battery cells, the two normal battery cells are conductively connected via a connector. When the faulty battery cell disconnects the conductive connection between a normal battery cell and an output terminal of the battery pack, the normal battery cell and the output terminal are conductively connected via a connector. When the faulty battery cell disconnects the conductive connection between two normal battery cells and another faulty battery cell disconnects the conductive connection between the normal battery cell and the output terminal of the battery pack, the two normal battery cells and the normal battery cell that was originally conductively connected to the output terminal via the faulty battery cell and the output terminal are conductively connected via a connector respectively.

[0056] Disconnecting the conductive connection means that only the original conductive connection of the faulty battery is disconnected, and the rest remains unchanged.

[0057] The connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar, so as to improve the reliability of the connection between two normal battery cells and / or between a normal battery cell and an output terminal.

[0058] Wherein, the poles of opposite names of adjacent battery cells are arranged adjacent to each other; the connector includes an intermediate connecting portion, and the end connecting portions arranged at both ends of the intermediate connecting portion are respectively oriented toward the positive pole of the normal battery cell and the negative pole of another normal battery cell and are conductively connected thereto and / or are respectively oriented toward the poles and output terminals of the normal battery cell that are conductively disconnected from the faulty battery cell and are conductively connected thereto, so as to realize the conductive connection of two normal battery cells and / or the conductive connection of the normal battery cell and the output terminal through the conductive connection between the intermediate connecting portion and the end connecting portion. At this time, the shape of the connector is similar to an "S" shape, and the connector saves materials while ensuring the normal use of the battery pack by replacing the original conductive connection of the faulty battery cell. Wherein, an insulating layer is provided on the outer surface of the intermediate connecting portion to ensure the safe use of the battery pack.

Claims

1. A battery pack, comprising a plurality of battery cells, wherein some of the battery cells have faulty battery cells, characterized in that: The faulty battery cell disconnects the conductive connection between two normal battery cells and / or between a normal battery cell and an output terminal of the battery pack, and the two normal battery cells and / or between a normal battery cell and the output terminal are conductively connected via a connector.

2. The battery pack according to claim 1, characterized in that: The connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar.

3. The battery pack according to claim 1, characterized in that: The opposite-name poles of adjacent battery cells are arranged adjacent to each other; the connector includes an intermediate connecting portion, and the end connecting portions arranged at both ends of the intermediate connecting portion are respectively oriented toward the positive pole of the normal battery cell and the negative pole of another normal battery cell and are conductively connected thereto and / or are respectively oriented toward the poles of the normal battery cell and the faulty battery cell that are conductively disconnected and the output terminal and are conductively connected thereto, so as to realize the conductive connection of the two normal battery cells and / or the conductive connection of the normal battery cell and the output terminal through the conductive connection between the intermediate connecting portion and the end connecting portion.

4. The battery pack according to claim 3, characterized in that: An insulating layer is provided on the outer surface of the intermediate connecting portion.

5. A battery pack structure for repairing a single cell failure in a battery pack, comprising a plurality of cells, some of which are faulty cells, characterized in that: The faulty battery cell disconnects the conductive connection between two normal battery cells and / or between a normal battery cell and an output terminal of the battery pack, and the two normal battery cells and / or between a normal battery cell and the output terminal are conductively connected via a connector.

6. The battery pack structure for repairing a single cell failure in a battery pack according to claim 5, characterized in that: The connecting piece is an aluminum bar or a copper bar or an aluminum busbar or a copper busbar.

7. The battery pack structure for repairing a single cell failure in a battery pack according to claim 5, characterized in that: The opposite-name poles of adjacent battery cells are arranged adjacent to each other; the connector includes an intermediate connecting portion, and the end connecting portions arranged at both ends of the intermediate connecting portion are respectively oriented toward the positive pole of the normal battery cell and the negative pole of another normal battery cell and are conductively connected thereto and / or are respectively oriented toward the poles of the normal battery cell and the faulty battery cell that are conductively disconnected and the output terminal and are conductively connected thereto, so as to realize the conductive connection of the two normal battery cells and / or the conductive connection of the normal battery cell and the output terminal through the conductive connection between the intermediate connecting portion and the end connecting portion.

8. The battery pack structure for repairing a single cell failure in a battery pack according to claim 7, characterized in that: An insulating layer is provided on the outer surface of the intermediate connecting portion.

9. The battery pack structure for repairing a single cell failure in a battery pack according to claim 5, characterized in that: The battery cell is also electrically connected to a collection unit via a sampling line, and the sampling lines at both ends of the faulty battery cell are electrically connected to the connector.

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