Lithium battery module

Abstract

The utility model relates to a lithium battery module, which comprises a battery pack, a PCB (printed circuit board) and a heat exchange board, the battery pack is fixed between the PCB and the heat exchange board, the battery pack comprises a plurality of cylindrical cells which face the same direction and are arranged side by side, one end of each cylindrical cell with an anode is a welding end, the other end of each cylindrical cell is a temperature control end, and the welding ends face the PCB. The positive electrode and the negative electrode of the cylindrical battery cell are respectively connected with the two busbars on the PCB at the welding end through an aluminum wire, the heat exchange plate is in contact with the temperature control end of the cylindrical battery cell, and heat exchange is carried out between the heat exchange plate and the cylindrical battery cell so as to maintain the temperature of the cylindrical battery cell. According to the lithium battery module, the temperature of all the cylindrical battery cells is controlled through the heat exchange plate, the heat exchange plate can heat or refrigerate the cylindrical battery cells, the temperature consistency of all the cylindrical battery cells in the lithium battery module is ensured through heat conduction, and the temperature of the cylindrical battery cells is controlled to be a proper working temperature.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a lithium battery module. Background Art

[0002] Lithium batteries have the advantages of high energy density, no memory effect, low self-discharge and long cycle life, and have been widely used in various electronic devices, electric vehicles and energy storage systems. The performance and service life of lithium batteries are largely affected by their operating temperature. Too high or too low temperature will cause the performance and capacity of lithium batteries to decline.

[0003] There are slight differences in the performance of each battery cell inside a lithium battery module, which results in differences in the temperature of each battery cell inside the lithium battery module. However, the temperature control structure of existing lithium batteries is mostly set outside the lithium battery module, which controls the temperature of the entire lithium battery module. It is difficult to control the temperature of each battery cell in the lithium battery module to achieve consistency, so that the temperature difference between each battery cell still exists. When the ambient temperature fluctuates greatly or the heat dissipation demand is high, these temperature differences will be magnified, thereby affecting the overall performance and service life of the lithium battery. Utility Model Content

[0004] In order to solve the deficiencies of the prior art, the utility model provides a lithium battery module.

[0005] The utility model provides a lithium battery module, comprising a battery pack, a PCB board, and a heat exchange plate, wherein the battery pack is fixed between the PCB board and the heat exchange plate, the battery pack comprises a plurality of cylindrical cells that are oriented in the same direction and arranged side by side, the cylindrical cells having one end of a positive electrode that is arranged as a welding end, and the other end that is arranged as a temperature control end, the welding end being arranged toward the PCB board, the positive electrode and the negative electrode of the cylindrical cells being respectively connected to two bus bars on the PCB board at the welding end through an aluminum wire, the heat exchange plate being in contact with the temperature control end of the cylindrical cells, and heat exchange is performed between the heat exchange plate and the cylindrical cells to maintain the temperature of the cylindrical cells.

[0006] In some embodiments, the heat exchange plate includes a plurality of semiconductor refrigeration plates, a first heat conducting plate and a second heat conducting plate. The plurality of semiconductor refrigeration plates are electrically connected to each other and are sandwiched between the first heat conducting plate and the second heat conducting plate. The two side surfaces of the semiconductor refrigeration plates are in contact with the first heat conducting plate and the second heat conducting plate respectively. The first heat conducting plate is in contact with the temperature control end of the cylindrical battery core to form a heat transfer path.

[0007] In some embodiments, the second heat conducting plate is provided with a mounting groove, the semiconductor cooling sheet is arranged in the mounting groove, and two side surfaces of the semiconductor cooling sheet are respectively in contact with the surface of the first heat conducting plate and the bottom of the mounting groove.

[0008] In some embodiments, the heat exchange plate further includes a heat insulation plate, the heat insulation plate is sandwiched between the first heat conducting plate and the second heat conducting plate, the heat insulation plate is provided with a space avoiding position, and the semiconductor refrigeration plate is located at the space avoiding position.

[0009] In some embodiments, the thermal insulation board is a mica sheet.

[0010] In some of the embodiments, both side surfaces of the semiconductor refrigeration plate are connected to the surface of the first heat conducting plate and the bottom of the mounting groove through heat conducting silicone.

[0011] In some embodiments, the first heat conducting plate and the second heat conducting plate are both aluminum plates.

[0012] In some of the embodiments, two ends of the cylindrical battery core are respectively fixed to the PCB board and the first heat conducting plate by structural adhesive.

[0013] In some of the embodiments, the battery pack further includes a limiting bracket, which is clamped between three adjacent cylindrical battery cells to separate the adjacent cylindrical battery cells.

[0014] In some of the embodiments, an epoxy protection plate is arranged in parallel on the outer side of the PCB board.

[0015] Compared with the prior art, the utility model has the following beneficial effects: the two ends of the cylindrical battery cell are respectively set as the welding end and the temperature control end, the positive and negative electrodes of the cylindrical battery cell are welded and connected to the PCB board at the welding end, and all the cylindrical battery cells of the battery pack are connected in series and parallel through the PCB board, the temperature control end of each cylindrical battery cell of the battery pack is in contact with the heat exchange plate, the temperature of all the cylindrical battery cells is controlled by the heat exchange plate, the heat exchange plate can heat or cool the cylindrical battery cells, and the temperature consistency of all the cylindrical battery cells in the lithium battery module is ensured by heat conduction, and the temperature of the cylindrical battery cells is controlled at a suitable working temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the lithium battery module of an embodiment of the present application.

[0017] Figure 2 It is a schematic diagram of the exploded structure of the lithium battery module of an embodiment of the present application.

[0018] Figure 3 It is a schematic diagram of the assembly structure of the PCB board and the battery pack in the embodiment of the present application by welding with aluminum wire.

[0019] Figure 4 It is a schematic diagram of the assembly structure of the battery pack and the heat exchange plate of an embodiment of the present application.

[0020] Reference numerals: 1, battery pack; 11, cylindrical battery cell; 12, welding terminal; 13, temperature control terminal; 14, positive electrode; 15, negative electrode;

[0021] 2. PCB board; 21. busbar; 22. aluminum wire;

[0022] 3. Heat exchange plate;

[0023] 4. Semiconductor refrigeration chip; 41. Lead wire;

[0024] 5. The first heat conducting plate;

[0025] 6. Second heat conducting plate; 61. Mounting slot; 62. Wiring slot; 63. Fixing hole;

[0026] 7. Heat insulation board; 71. Avoid empty space;

[0027] 8. Limit bracket; 81. Arc groove;

[0028] 9. Epoxy protective plate; 91. Screw column. DETAILED DESCRIPTION

[0029] The specific implementation modes of the present utility model are introduced with reference to the accompanying drawings.

[0030] refer to Figure 1 The figure is a schematic diagram of the three-dimensional structure of the lithium battery module, which includes, from top to bottom, an epoxy protection board 9, a PCB board 2, a battery pack 1, and a heat exchange board 3. The PCB board 2 is used to connect the cylindrical cells 11 of the battery pack 1 in series and parallel to charge and discharge the lithium battery module. The heat exchange board 3 is used to perform heat exchange on the cylindrical cells 11 of the battery pack 1 to maintain the temperature of each cylindrical cell 11 within a stable range.

[0031] refer to Figures 1 to 4 A lithium battery module includes a battery pack 1, a PCB board 2, and a heat exchange plate 3. The battery pack 1 is fixed between the PCB board 2 and the heat exchange plate 3. The battery pack 1 includes a plurality of cylindrical cells 11 that are oriented in the same direction and arranged side by side. One end of the cylindrical cell 11 having a positive electrode 14 is set as a welding end 12, and the other end is set as a temperature control end 13. The welding end 12 is set toward the PCB board 2. The positive electrode 14 and the negative electrode 15 of the cylindrical cell 11 are respectively connected to two bus bars 21 on the PCB board 2 at the welding end 12 through an aluminum wire 22. The heat exchange plate 3 contacts the temperature control end 13 of the cylindrical cell 11. Heat exchange is performed between the heat exchange plate 3 and the cylindrical cell 11 to maintain the temperature of the cylindrical cell 11.

[0032] In the lithium battery module of the present embodiment, the two ends of the cylindrical battery cell 11 are respectively set as a welding end 12 and a temperature control end 13, the positive and negative electrodes 15 of the cylindrical battery cell 11 are welded and connected to the PCB board 2 at the welding end 12, and all the cylindrical battery cells 11 of the battery pack 1 are connected in series and parallel through the PCB board 2, and the temperature control end 13 of each cylindrical battery cell 11 of the battery pack 1 is in contact with the heat exchange plate 3, and the temperature of all the cylindrical battery cells 11 is controlled by the heat exchange plate 3. The heat exchange plate 3 can heat or cool the cylindrical battery cells 11, and the temperature consistency of all the cylindrical battery cells 11 in the lithium battery module is ensured by heat conduction, and the temperature of the cylindrical battery cells 11 is controlled at a suitable working temperature.

[0033] It should be further explained that the bus 21 on the PCB board 2 is S-shaped, and the same bus 21 is welded to the positive electrodes 14 or negative electrodes 15 of multiple cylindrical battery cells 11 through aluminum wires 22. Through multiple bus bars 21, all cylindrical battery cells 11 of the entire battery pack 1 are connected in series and parallel.

[0034] In order to achieve heating and cooling of the cylindrical battery cell 11, in this embodiment, reference Figure 1 and Figure 2 The heat exchange plate 3 includes a plurality of semiconductor refrigeration sheets 4, a first heat conducting plate 5 and a second heat conducting plate 6. The plurality of semiconductor refrigeration sheets 4 are electrically connected to each other. The plurality of semiconductor refrigeration sheets 4 are sandwiched between the first heat conducting plate 5 and the second heat conducting plate 6. The two side surfaces of the semiconductor refrigeration sheets 4 are in contact with the first heat conducting plate 5 and the second heat conducting plate 6 respectively. The first heat conducting plate 5 is in contact with the temperature control end 13 of the cylindrical battery core 11 to form a heat transfer path.

[0035] It can be understood that, with such an arrangement, the six semiconductor refrigeration plates 4 are connected in series with each other and have the same working state. The heating or cooling is switched by changing the polarity of the semiconductor refrigeration plate 4. When the temperature sensor-thermistor in the battery module detects that the temperature of the cylindrical battery cell 11 is low, the semiconductor refrigeration plate 4 is controlled to heat and heat up. When the temperature of the cylindrical battery cell 11 is detected to be high, the semiconductor refrigeration plate 4 is controlled to cool and cool down. Heat is transferred between the cylindrical battery cell 11, the first heat conduction plate 5 and the semiconductor refrigeration plate 4, thereby realizing temperature control of the cylindrical battery cell 11. Each cylindrical battery cell 11 is in contact with the first heat conduction plate 5, and the heat of each cylindrical battery cell 11 can be quickly transferred to the first heat conduction plate 5, thereby ensuring that each cylindrical battery cell 11 maintains a consistent temperature.

[0036] It should be further explained that the cooling and heating of the semiconductor refrigeration sheet 4 mentioned above are aimed at the first heat conducting plate 5 side of the semiconductor refrigeration sheet 4. According to the characteristics of the semiconductor refrigeration sheet 4, when cooling is performed on the first heat conducting plate 5 side of the semiconductor refrigeration sheet 4, the second heat conducting plate 6 side of the semiconductor refrigeration sheet 4 is heated up. Similarly, when heating is performed on the first heat conducting plate 5 side of the semiconductor refrigeration sheet 4, the second heat conducting plate 6 side of the semiconductor refrigeration sheet 4 is cooled down.

[0037] In order to install the semiconductor cooling sheet 4, in this embodiment, refer to Figure 2 The second heat conducting plate 6 is provided with a mounting groove 61 , the semiconductor cooling sheet 4 is arranged in the mounting groove 61 , and the two side surfaces of the semiconductor cooling sheet 4 are in contact with the surface of the first heat conducting plate 5 and the bottom of the mounting groove 61 respectively.

[0038] It is understandable that, with such a configuration, the semiconductor refrigeration sheet 4 is a semiconductor product, and its own material does not have very high mechanical strength. The entire weight of the battery pack 1 and some external forces can easily squeeze and damage the semiconductor refrigeration sheet 4. The semiconductor refrigeration sheet 4 is clamped between the first heat conducting plate 5 and the second heat conducting plate 6. The mounting groove 61 can accommodate the semiconductor refrigeration sheet 4, so that the weight of the battery pack 1 and some external forces will be transmitted between the first heat conducting plate 5 and the second heat conducting plate 6, and will not be directly transmitted to the semiconductor refrigeration sheet 4, thereby protecting the semiconductor refrigeration sheet 4. At the same time, the semiconductor refrigeration sheet 4 is placed through the mounting groove 61, and the groove wall of the mounting groove 61 can limit and position the semiconductor refrigeration sheet 4, making the installation of the semiconductor refrigeration sheet 4 easier.

[0039] In order to avoid heat transfer between the first heat conducting plate 5 and the second heat conducting plate 6, in this embodiment, reference Figure 2 and Figure 4 The heat exchange plate 3 further includes a heat insulation plate 7 , which is sandwiched between the first heat conducting plate 5 and the second heat conducting plate 6 . The heat insulation plate 7 is provided with a space avoiding position 71 , and the semiconductor cooling plate 4 is located at the space avoiding position 71 .

[0040] It can be understood that in order to avoid mutual heat transfer between the first heat conducting plate 5 and the second heat conducting plate 6 and weaken the heating and cooling effect of the semiconductor refrigeration plate 4 on the cylindrical battery cell 11, the first heat conducting plate 5 is separated from the second heat conducting plate 6 by the insulation plate 7, so that the first heat conducting plate 5 and the second heat conducting plate 6 cannot be in direct contact with each other, cutting off the heat transfer therebetween, and ensuring that the second heat conducting plate 6 will not interfere with the cooling and heating operations of the semiconductor refrigeration plate on the first heat conducting plate 5 and the cylindrical battery cell 11.

[0041] In order to ensure that the heat insulation board 7 has a certain mechanical strength, in this embodiment, the heat insulation board 7 is a mica sheet.

[0042] It can be understood that, with such a configuration, the mica sheet has very high insulation and heat-insulating properties, good chemical stability, and resistance to strong acids, strong alkalis and pressure. The mica sheet can ensure good electrical insulation and heat-insulating properties between the first thermally conductive sheet and the second thermally conductive sheet. At the same time, it can also withstand force, so that the weight of the battery pack 1 can be transferred to the second thermally conductive sheet through the mica sheet, thereby protecting the safety of the semiconductor refrigeration sheet 4.

[0043] It should be further explained that the second heat conducting plate 6 is provided with a wiring groove 62 which is connected with the mounting groove 61, and the lead 41 of the semiconductor refrigeration plate 4 extends from the wiring groove 62 to the outside of the heat exchange plate 3, and the edges of the first heat conducting plate 5 and the second heat conducting plate 6 are provided with fixing holes 63, and the fixing holes 63 fix the first heat conducting plate 5, the second heat conducting plate 6 and the mica sheet together by rivets or screws.

[0044] In order to ensure the cooling and heating effect of the semiconductor refrigeration sheet 4 on the cylindrical battery core 11, in this embodiment, both side surfaces of the semiconductor refrigeration sheet 4 are connected to the surface of the first heat conducting plate 5 and the bottom of the mounting groove 61 through thermally conductive silicone.

[0045] It can be understood that, with such a configuration, the thermally conductive silicone can be filled into the gap between the surface of the first heat conductive plate 5 and the surface of the semiconductor refrigeration sheet 4, and between the bottom of the mounting groove 61 and the surface of the semiconductor refrigeration sheet 4, so that heat can be quickly transferred between the first heat conductive plate 5 and the semiconductor refrigeration sheet 4, and between the second heat conductive plate 6 and the semiconductor refrigeration sheet 4, thereby ensuring the cooling and heating effect of the semiconductor refrigeration sheet 4 on the cylindrical battery cell 11.

[0046] In order to ensure the cooling and heating effects of the heat exchange plate 3 on the cylindrical battery core 11, in this embodiment, the first heat conduction plate 5 and the second heat conduction plate 6 are both aluminum plates.

[0047] It can be understood that, in such a configuration, the first heat conduction plate 5 is an alumina plate, which has high strength, wear resistance, corrosion resistance, and good thermal conductivity. It can well complete the heat transfer between the cylindrical battery cell 11 and the semiconductor refrigeration plate 4, and improve the cooling and heating effect of the heat exchange plate 3 on the cylindrical battery cell 11. The second heat conduction plate 6 is an aluminum alloy profile, which has high strength, wear resistance, corrosion resistance, and good thermal conductivity. It can quickly transfer heat with the semiconductor refrigeration plate 4. At the same time, it is convenient to process structures such as the installation groove 61.

[0048] In order to fix the cylindrical battery cell 11 , in the present embodiment, two ends of the cylindrical battery cell 11 are respectively fixed to the PCB board 2 and the first heat conducting plate 5 by means of structural adhesive.

[0049] It is understandable that with such a configuration, if high-temperature welding is used to fix the cylindrical battery cell 11, it is easy to damage it. If a plastic bracket is used, it will block heat transfer to a certain extent. The cylindrical battery cell 11 is fixed between the PCB board 2 and the first heat conductive plate 5 by means of structural adhesive, and multiple cylindrical battery cells 11 are combined into a battery pack 1. The structural adhesive fixing method can reduce the redundant structure in the battery pack 1, which is beneficial to the cooling and heating of the cylindrical battery cell 11.

[0050] In order to ensure that the spacing between the cylindrical cells 11 is consistent, in this embodiment, Figure 4 The battery pack 1 also includes a limiting bracket 8 , which is sandwiched between three adjacent cylindrical battery cells 11 to separate the adjacent cylindrical battery cells 11 .

[0051] It can be understood that, with such a configuration, the limit bracket 8 is triangular in shape, and the limit bracket 8 has three identical arc-shaped grooves 81 to contact the three cylindrical battery cells 11. The cylindrical battery cell 11 is an 18650 cylindrical battery cell 11. The outer shell of the cylindrical battery cell 11 is a metal shell with a certain strength. The three adjacent cylindrical battery cells 11 are separated by the limit bracket 8 to ensure that the spacing between the cylindrical battery cells 11 is consistent, thereby avoiding short circuits caused by tight contact between the cylindrical battery cells 11.

[0052] In order to protect the lithium battery module, in this embodiment, reference Figure 1 An epoxy protection plate 9 is arranged parallel to the outer side of the PCB board 2 .

[0053] It is understandable that, with such a configuration, the epoxy protection plate 9 is separated from the PCB board 2 by a plurality of screw columns 91. The epoxy protection plate 9 has insulation and certain mechanical properties, and can buffer some external forces, thereby protecting the lithium battery module and preventing the aluminum wire 22 from being damaged.

[0054] The embodiment of the present application adopts a limiting bracket 8 to ensure that the spacing between the cylindrical cells 11 is consistent and to avoid short circuits between the cylindrical cells 11; the bottom of the battery pack 1 is fixed with a first heat conducting plate 5 of an alumina plate, and the two ends of the cylindrical cells 11 are respectively set as a welding end 12 and a temperature control end 13, and the positive and negative electrodes 15 of the cylindrical cells 11 are welded and connected to the PCB board 2 at the welding end 12, and all the cylindrical cells 11 of the battery pack 1 are connected in series and parallel through the PCB board 2, and the temperature control end 13 of each cylindrical cell 11 of the battery pack 1 is connected to the heat exchange end 12. The heat exchange plate 3 is in contact with the cylindrical battery cells 11, and the temperature of all the cylindrical battery cells 11 is controlled by the heat exchange plate 3. The heating or cooling is switched by changing the polarity of the semiconductor refrigeration plate 4. When it is detected that the temperature of the cylindrical battery cell 11 is low, the semiconductor refrigeration plate 4 is controlled to heat and heat up. When it is detected that the temperature of the cylindrical battery cell 11 is high, the semiconductor refrigeration plate 4 is controlled to cool and cool down. The temperature consistency of all the cylindrical battery cells 11 in the lithium battery module is ensured through heat conduction, and the temperature of the cylindrical battery cell 11 is controlled at a suitable working temperature to improve the quality of the lithium battery module.

[0055] The above does not limit the technical scope of the present invention. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A lithium battery module, characterized in that: The invention comprises a battery pack, a PCB board, and a heat exchange plate. The battery pack is fixed between the PCB board and the heat exchange plate. The battery pack comprises a plurality of cylindrical cells that are arranged in the same direction and side by side. One end of the cylindrical cell having a positive electrode is set as a welding end, and the other end is set as a temperature control end. The welding end is set toward the PCB board. The positive electrode and the negative electrode of the cylindrical cell are respectively connected to two bus bars on the PCB board at the welding end through an aluminum wire. The heat exchange plate contacts the temperature control end of the cylindrical cell. Heat exchange is performed between the heat exchange plate and the cylindrical cell to maintain the temperature of the cylindrical cell.

2. The lithium battery module according to claim 1, characterized in that: The heat exchange plate includes a plurality of semiconductor refrigeration plates, a first heat conducting plate and a second heat conducting plate. The plurality of semiconductor refrigeration plates are electrically connected to each other and are sandwiched between the first heat conducting plate and the second heat conducting plate. The two side surfaces of the semiconductor refrigeration plates are in contact with the first heat conducting plate and the second heat conducting plate respectively. The first heat conducting plate is in contact with the temperature control end of the cylindrical battery core to form a heat transfer path.

3. The lithium battery module according to claim 2, characterized in that: The second heat conducting plate is provided with a mounting groove, the semiconductor cooling sheet is arranged in the mounting groove, and two side surfaces of the semiconductor cooling sheet are respectively in contact with the surface of the first heat conducting plate and the bottom of the mounting groove.

4. The lithium battery module according to claim 3, characterized in that: The heat exchange plate further comprises a heat insulation plate, wherein the heat insulation plate is sandwiched between the first heat conducting plate and the second heat conducting plate, and the heat insulation plate is provided with a space avoiding position, and the semiconductor refrigeration plate is located at the space avoiding position.

5. The lithium battery module according to claim 4, characterized in that: The heat insulation board is a mica sheet.

6. The lithium battery module according to claim 3, characterized in that: Both side surfaces of the semiconductor refrigeration plate are connected to the surface of the first heat conducting plate and the bottom of the mounting groove through heat conducting silica gel.

7. The lithium battery module according to claim 2, characterized in that: The first heat conducting plate and the second heat conducting plate are both aluminum plates.

8. The lithium battery module according to claim 2, characterized in that: The two ends of the cylindrical battery core are respectively fixed to the PCB board and the first heat conducting plate by structural adhesive.

9. The lithium battery module according to claim 1, characterized in that: The battery pack further includes a limiting bracket, which is clamped between three adjacent cylindrical battery cells to space the adjacent cylindrical battery cells apart.

10. The lithium battery module according to claim 1, characterized in that: An epoxy protection plate is arranged parallel to the outer side of the PCB board.

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