Battery pack

Abstract

The utility model relates to the technical field of batteries, in particular to a battery pack, the battery pack comprises a box body, at least one battery row, a heat exchange part, a confluence part and a limiting part, the battery row is arranged in the box body, the battery row comprises a plurality of cylindrical batteries arranged in sequence, the axis of the cylindrical batteries is perpendicular to the arrangement direction of the batteries, and the heat exchange part is arranged in the box body. The positive electrode end and the negative electrode end of the cylindrical battery are arranged on the same side of the cylindrical battery; the heat exchange piece is used for exchanging heat with the battery; the bus piece is used for electrically connecting the plurality of cylindrical batteries; the limiting piece is used for limiting the battery; wherein the cylindrical battery is provided with a first end wall, a second end wall and a peripheral wall, the first end wall and the second end wall are oppositely arranged, the peripheral wall is located between the first end wall and the second end wall, the heat exchange piece and the first end wall are oppositely arranged, the confluence piece and the second end wall are oppositely arranged, and the limiting piece and the peripheral wall are oppositely arranged.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular, to a battery pack. Background Art

[0002] Electric vehicles are often equipped with battery packs, which are used to provide power to the electric vehicles. The battery pack includes multiple batteries, a busbar and a heat exchanger. The busbar is used to electrically connect multiple batteries, and the heat exchanger is used to exchange heat with the batteries, for example, to cool or heat the batteries. In the related art, the busbar and the heat exchanger are in contact, and the heat exchanger will produce condensation when cooling the battery. After the condensation flows to the heat exchanger, it may cause a short circuit in the battery pack.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0004] An object of the present disclosure is to provide a battery pack, thereby reducing the short circuit risk of the battery pack at least to a certain extent.

[0005] The present disclosure provides a battery pack, the battery pack comprising:

[0006] A box body, wherein the box body has a bottom plate;

[0007] At least one battery row, the battery row is arranged in the box, the battery row includes a plurality of cylindrical batteries arranged in sequence, the axis of the cylindrical battery is perpendicular to the arrangement direction of the battery, and the positive output terminal and the negative output terminal of the cylindrical battery are arranged on the same side of the cylindrical battery;

[0008] A heat exchange element, the heat exchange element being used for exchanging heat with the battery;

[0009] A busbar, the busbar being used to electrically connect a plurality of the cylindrical batteries;

[0010] A limiting member, the limiting member is used to limit the battery in a direction perpendicular to the axis;

[0011] Among them, the cylindrical battery has a first end wall and a first end wall that are arranged opposite to each other, and a peripheral wall located between the first end wall and the second end wall, the heat exchange member and the first end wall are arranged opposite to each other, the collector and the second end wall are arranged opposite to each other, and the limit member and the peripheral wall are arranged opposite to each other.

[0012] The battery pack provided by the embodiment of the present disclosure includes a box body, a battery row, a heat exchanger, a collector and a limiter. The box body has a bottom plate, the battery row is arranged in the box body, and the axis of the cylindrical battery in the battery row is parallel to the bottom plate, the cylindrical battery has a first end wall, a second end wall and a peripheral wall that are not coplanar, the heat exchanger and the first end wall of the cylindrical battery are arranged relative to each other, the collector and the second end wall of the cylindrical battery are arranged relative to each other, and the limiter and the peripheral wall of the cylindrical battery are arranged relative to each other, that is, the collector and the heat exchanger are arranged on different sides of the cylindrical battery, which prevents condensation on the heat exchanger from flowing to the collector and reduces the risk of short circuit in the battery pack. In addition, the collector and the heat exchanger are arranged on different sides, which solves the problem that when the collector and the heat exchanger are on the same side, the metal collector will be subjected to repeated temperature differences, thereby causing metal fatigue, which is not conducive to improving the reliability of high-voltage connection.

[0013] Furthermore, the heat exchanger, busbar and limiter are respectively located on different sides of the cylindrical battery, thereby avoiding the problem of interference between the heat exchanger, busbar and limiter when the battery pack is assembled. The limiter and busbar are arranged on different sides, which solves the problem that when the limiter and busbar are arranged on the same side, the limiter needs to be made of insulating material due to the insulation requirements between the busbar and the limiter, which leads to low strength of the limiter (the strength of insulating materials is often lower than that of metal materials), thereby improving the strength of the limiter and thus improving the stability of the internal structure of the battery pack. The limiter and the heat exchange plate are arranged on different sides, which solves the problem of poor structural stability of the battery pack caused by the heat exchange plate and the limiter being arranged on the same side, thereby improving the structural stability of the battery pack.

[0014] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0016] Figure 1 A schematic diagram of the structure of a battery pack provided by an exemplary embodiment of the present disclosure;

[0017] Figure 2 A schematic diagram of the structure of a battery provided for an exemplary embodiment of the present disclosure;

[0018] Figure 3 A schematic diagram of the structure of another battery pack provided by an exemplary embodiment of the present disclosure;

[0019] Figure 4A schematic structural diagram of a position limiting member provided in an exemplary embodiment of the present disclosure.

[0020] In the figure:

[0021] 10. Box body; 11. Bottom plate; 12. Frame; 20. Battery row; 21. Cylindrical battery; 211. Shell; 212. Pole; 201. First end wall; 202. Second end wall; 203. Peripheral wall; 30. Heat exchange component; 40. Bus bar; 41. Bus bar; 50. Limiting component; 51. Main body; 52. Extension portion. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings in the exemplary embodiments of the present disclosure to clearly and completely describe the technical solutions in the exemplary embodiments of the present disclosure. The exemplary embodiments described herein are only for illustrative purposes and are not intended to limit the scope of protection of the present disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of the present disclosure.

[0023] In the description of the present disclosure, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; the term "plurality" refers to two or more; the term "and / or" includes any and all combinations of one or more associated listed items. In particular, reference to "the / the" object or "an" object is also intended to indicate one of a possible plurality of such objects.

[0024] Unless otherwise specified or explained, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0025] Further, in the description of the present disclosure, it should be understood that the directional words such as "upper", "lower", "inner", "outer" and the like described in the exemplary embodiments of the present disclosure are described at the angles shown in the accompanying drawings and should not be understood as limitations on the exemplary embodiments of the present disclosure. It should also be understood that, in the context, when it is mentioned that an element or feature is connected to another element (one or more) "upper", "lower", or "inner", "outer", it can not only be directly connected to the other (one or more) elements "upper", "lower", "inner", "outer", but also can be indirectly connected to the other (one or more) elements "upper", "lower", "inner", "outer" through an intermediate element.

[0026] The exemplary embodiment of the present disclosure provides a battery pack, such as Figure 1 and Figure 2 As shown, the battery pack includes: a box body 10, at least one battery row 20, a heat exchanger 30, a current collector 40 and a stopper 50, the box body 10 has a bottom plate 11; the battery row 20 is arranged in the box body 10, and the battery row 20 includes a plurality of cylindrical batteries 21 arranged in sequence, the axis of the cylindrical battery 21 is perpendicular to the arrangement direction of the battery, and the positive output terminal and the negative output terminal of the cylindrical battery 21 are arranged on the same side of the cylindrical battery 21; the heat exchanger 30 is used for exchanging heat with the battery; the current collector 40 is used for electrically connecting a plurality of cylindrical batteries 21; the stopper 50 is used for limiting the battery in a direction perpendicular to the axis;

[0027] Among them, the cylindrical battery 21 has a first end wall 201 and a second end wall 202 that are arranged opposite to each other, and a peripheral wall 203 located between the first end wall and the second end wall, the heat exchange component 30 and the first end wall 201 are arranged opposite to each other, the collector 40 and the second end wall 202 are arranged opposite to each other, and the limit component 50 and the peripheral wall 203 are arranged opposite to each other.

[0028] The battery pack provided by the embodiment of the present disclosure includes a box body 10, a battery row 20, a heat exchanger 30, a collector 40 and a stopper 50. The box body 10 has a bottom plate 11. The battery row 20 is arranged in the box body 10, and the axis of the cylindrical battery 21 in the battery row 20 is parallel to the bottom plate 11. The cylindrical battery 21 has a first end wall 201, a second end wall 202 and a peripheral wall 203 that are not coplanar. The heat exchanger 30 and the first end wall 201 are arranged opposite to each other, and the collector 40 and the second end wall 202 are arranged opposite to each other. The limit member 50 and the surrounding wall 203 are arranged relative to each other, that is, the bus 40 and the heat exchanger 30 are arranged on different sides of the cylindrical battery 21, which prevents condensation on the heat exchanger 30 from flowing to the bus 40, reduces the risk of short circuit in the battery pack, and the bus 40 and the heat exchanger 30 are arranged on different sides, which solves the problem that when the bus 40 and the heat exchanger 30 are on the same side, the metal bus 40 will be subjected to repeated temperature differences, thereby generating metal fatigue, which is not conducive to improving the reliability of high-voltage connection.

[0029] Furthermore, the heat exchanger 30, the busbar 40 and the limiter 50 are respectively located on different sides of the cylindrical battery 21, thereby avoiding the problem of interference between the heat exchanger 30, the busbar 40 and the limiter 50 when the battery pack is assembled. The limiter 50 and the busbar 40 are arranged on different sides, which solves the problem that when the limiter 50 and the busbar 40 are arranged on the same side, the limiter 50 needs to be made of insulating material due to the insulation requirements between the busbar 41 and the limiter 50, which leads to low strength of the limiter 50 (the strength of insulating materials is often lower than that of metal materials), thereby improving the strength of the limiter 50 and thus improving the stability of the internal structure of the battery pack. The limiter 50 and the heat exchange plate are arranged on different sides, which solves the problem of poor structural stability of the battery pack caused by the heat exchange plate and the limiter 50 being arranged on the same side, thereby improving the structural stability of the battery pack.

[0030] Furthermore, the heat exchange component 30 and the collector 40 are respectively arranged at the two ends of the cylindrical battery 21, and the limit component 50 is arranged on the peripheral wall 203 of the cylindrical battery 21. This solves the problem that when the heat exchange component 30 is arranged on the outer ring surface of the cylindrical battery 21, it is difficult to ensure the fit between the arc surface and the heat exchange component, thereby failing to meet a higher heat exchange efficiency. If the heat exchange component 30 is made into an arc surface, the cost and manufacturing difficulty will be increased. Therefore, the setting of the limit component 50 on the outer ring surface is not only beneficial to the whole package mode, but also more cost-effective.

[0031] The following is a detailed description of each part of the battery pack provided by the embodiment of the present disclosure:

[0032] like Figure 3 As shown, the box body 10 includes a bottom plate 11 and a frame 12, the frame 12 is arranged on the bottom plate 11, and at least one battery compartment is formed on the bottom plate 11, and the battery compartment is used to accommodate devices such as a battery row 20. For example, the frame 12 can be arranged on the top surface of the bottom plate 11, and the frame 12 and the bottom plate 11 are connected by welding, riveting or bolting. Or the frame 12 can surround the bottom plate 11, and the frame 12 and the bottom plate 11 are connected by welding, riveting or bolting.

[0033] The bottom plate 11 may be a single-layer structure, for example, the bottom plate 11 is a support plate for supporting the battery. Alternatively, the bottom plate 11 may be a multi-layer composite structure, for example, the bottom plate 11 includes a support plate and a bottom guard plate, the support plate is used to support the battery, the bottom guard plate is arranged on a side of the support plate away from the battery row 20, and the bottom guard plate is used to seal and protect the support plate and the battery row 20.

[0034] The frame 12 includes a plurality of structural beams, and the plurality of structural beams are disposed on the bottom plate 11 to form one or more battery compartments on the bottom plate 11. In a feasible embodiment, the frame 12 includes a plurality of side beams, and the plurality of side beams are sequentially connected end to end to form a battery compartment. For example, the frame 12 is a rectangular or approximately rectangular structure, and the frame 12 includes four side beams, and the four side beams are sequentially connected end to end to form a rectangular frame 12.

[0035] In another feasible embodiment, the frame 12 includes a plurality of side beams and a middle beam, and the plurality of side beams are connected end to end to form the frame 12, and the middle beam is disposed in the frame 12, and the middle beam divides the space in the frame 12 into a plurality of battery compartments. For example, a middle beam is disposed in the frame 12, and the middle beam divides the space in the frame 12 into two battery compartments. Alternatively, two middle beams are disposed in the frame 12, and the two middle beams are disposed vertically to divide the space in the frame 12 into four battery compartments.

[0036] Alternatively, the frame 12 may include a plurality of side beams and partition beams, wherein the plurality of side beams are connected end to end in sequence to form the frame 12, and the partition beams are disposed in the frame 12, and the partition beams divide the space in the frame 12 into a battery compartment and an electrical compartment, wherein the battery compartment is used to accommodate the battery row 20, and the electrical compartment is used to accommodate electrical components such as a battery management system.

[0037] The battery row 20 is arranged in the box 10, and the battery row 20 includes a plurality of cylindrical batteries 21 arranged in sequence, the axis of the cylindrical battery 21 is perpendicular to the arrangement direction of the battery, and the axis of the battery is parallel to the bottom plate 11. For example, the plurality of cylindrical batteries 21 in the battery row 20 are arranged along a first direction, the axis of the cylindrical battery 21 is arranged along a second direction, the second direction is perpendicular to the first direction, and the second direction is perpendicular to the bottom plate 11. The plurality of cylindrical batteries 21 in the battery row 20 are aligned, that is, the end faces of the plurality of cylindrical batteries 21 are flush.

[0038] It should be noted that, in the embodiment of the present disclosure, the axis of the cylindrical battery 21 is parallel to the bottom plate 11, which can be understood as being approximately parallel, that is, when the angle between the axis of the cylindrical battery 21 and the bottom plate 11 is less than a preset angle, the cylindrical battery 21 and the bottom plate 11 are considered to be parallel. For example, if the angle between the cylindrical battery 21 and the bottom plate 11 is less than 10 degrees, the cylindrical battery 21 and the bottom plate 11 are considered to be parallel. The axis of the cylindrical battery 21 is perpendicular to the arrangement direction of the battery, which can be understood as being approximately perpendicular, that is, if the angle between the axis of the cylindrical battery 21 and the arrangement direction of the battery is within a preset range, the axis of the cylindrical battery 21 is considered to be perpendicular to the arrangement direction of the battery, for example, the preset range can be 85 degrees to 95 degrees.

[0039] A plurality of battery rows 20 and a stopper 50 can be installed in the box 10 in the form of a battery pack, and the battery pack includes two battery rows 20 and a stopper 50 disposed between the battery rows 20. A heat exchanger 30 is disposed between adjacent battery packs, and two adjacent battery packs share the heat exchanger 30, which can save costs, and the space in the battery pack is conducive to improving the energy density of the battery.

[0040] The cylindrical battery 21 has a non-coplanar first end wall 201, a second end wall 202 and a peripheral wall 203. The heat exchanger 30 is disposed opposite to the first end wall 201 of the cylindrical battery 21, the current collector 40 is disposed opposite to the second end wall 202 of the cylindrical battery 21, and the stopper 50 is disposed opposite to the peripheral wall 203 of the cylindrical battery 21. The axis of the cylindrical battery 21 refers to the rotational symmetry axis of the cylindrical battery, such as Figure 2 As shown, the axis of the cylindrical battery is X.

[0041] For example, the cylindrical battery 21 may include a shell 211, a battery cell and a pole 212, wherein the shell 211 is provided with a receiving cavity, the battery cell is provided in the receiving cavity, and the pole 212 is provided in the shell 211. In the cylindrical battery 21, the pole 212 is one electrode end of the cylindrical battery 21, the shell 211 is another electrode end of the cylindrical battery 21, and the battery cell is electrically connected to the pole 212 and the shell 211, respectively. For example, the pole 212 is the positive output end of the battery, and the second end wall 202 of the shell 211 is the negative output end. Of course, in some embodiments, the shell 211 may also be provided with a first pole and a second pole, the first pole being connected to the positive terminal and the positive lug, and the second pole being connected to the negative terminal and the negative lug.

[0042] The first pole and the second pole are both disposed on the second end wall 202 .

[0043] The housing 211 may include a first end plate, a second end plate and a cylinder, the cylinder is a hollow structure and has openings at both ends of the cylinder, and the first end plate and the second end plate are respectively sealed at both ends of the cylinder. For example, the first end plate forms the first end wall 201 of the cylindrical battery 21, the second end plate forms the second end wall 202 of the cylindrical battery 21, and the cylinder forms the peripheral wall 203 of the cylindrical battery 21. Of course, in practical applications, the first end wall 201, the second end wall 202 and the peripheral wall 203 may also be distributed in other ways, and the embodiments of the present disclosure are not limited thereto.

[0044] Among them, the pole 212 can be arranged on the first end plate. The cylinder and the first end plate are an integrally formed structure, and the cylinder and the second end plate are a split-formed structure. For example, the cylinder and the first end plate are integrally formed by stamping, and the second end plate and the cylinder are connected by welding or riveting. Or the cylinder and the first end plate are a split-formed structure, and the cylinder and the second end plate are an integrally formed structure, for example, the cylinder and the second end plate are integrally formed by stamping, and the first end plate and the cylinder are connected by welding or riveting.

[0045] The housing 211 is made of a conductive material, and the material of the housing 211 may be steel, aluminum, nickel, cadmium, manganese, tungsten or copper, etc. The first end plate, the second end plate and the cylinder may be made of the same material, or the first end plate, the second end plate and the cylinder may be made of different materials.

[0046] The battery cell includes a battery cell body, a first pole ear and a second pole ear, wherein the first pole ear and the second pole ear extend from the battery cell body respectively, and the first pole ear is electrically connected to the pole column 212 , and the second pole ear is electrically connected to the shell 211 .

[0047] Optionally, the first pole ear and the second pole ear extend from one end of the battery body close to the first end plate. On this basis, a current collecting assembly is arranged between the battery body and the first end plate, and the current collecting assembly includes a first current collecting member and a second current collecting member, the first current collecting member connects the first pole ear and the pole 212, and the second current collecting member connects the second pole ear and the housing 211.

[0048] Alternatively, the first pole ear extends from one end of the battery cell body close to the first end plate, and the second pole ear extends from one end of the battery cell body close to the second end plate. The first pole ear is connected to the pole 212 through the first current collector, and the second pole ear is connected to the shell 211 through the second current collector.

[0049] It should be noted that in the embodiment of the present disclosure, the cylindrical battery 21 is not limited to using the pole 212 as one electrode and the shell 211 as another electrode. For example, the shell 211 may be provided with a first pole and a second pole, the first pole and the second pole are insulated, the first pole is connected to the first pole tab, and the second pole is connected to the second pole tab.

[0050] The battery cell may be a wound battery cell, the battery cell includes a first pole piece, a second pole piece and a diaphragm sheet, the first pole piece and the second pole piece have opposite electrical properties, for example, the first pole piece is a positive pole piece, and the second pole piece is a negative pole piece. The diaphragm sheet is disposed between the first pole piece and the second pole piece, and is wound to obtain a wound battery cell. Of course, in practical applications, the battery cell may also be a laminated battery cell, and the embodiments of the present disclosure are not limited thereto.

[0051] In a feasible embodiment, the cylindrical battery 21 is a lithium iron phosphate battery, and the dimension of the cylindrical battery 21 along the axis is greater than or equal to 60 mm. In practical applications, the size of the single cell of a cylindrical lithium iron phosphate battery directly affects the cost of the battery, and the larger the single cell, the greater the cost advantage. Therefore, setting the dimension of the cylindrical battery 21 along the axis to be greater than or equal to 60 mm can effectively control the cost of the battery. Setting the axis of the cylindrical battery 21 to be parallel to the bottom plate 11 effectively saves space in the height direction and solves the problem of insufficient installation space in the height direction of the vehicle due to the excessive height of the single cell.

[0052] The dimension of the cylindrical battery 21 along the axis is L, the dimension of the battery pack along the height direction is H, the height direction is perpendicular to the bottom plate 11, L>H. Furthermore, L≥2H. Setting the axis of the cylindrical battery 21 to be parallel to the bottom plate 11 not only ensures that the large single cylindrical battery 21 has a cost advantage, but also effectively saves space in the height direction, solving the problem of insufficient installation space in the height direction of the vehicle due to the excessive height of the single battery.

[0053] The cylindrical battery 21 is provided with an explosion-proof valve, and the explosion-proof valve is not provided on the first end wall 201 of the cylindrical battery 21, so as to avoid the explosion of the explosion-proof valve which may damage the heat exchange component 30, or even cause the cooling medium to flow out, resulting in a short circuit and thermal runaway.

[0054] For example, the pole 212 and the explosion-proof valve of the cylindrical battery 21 are both arranged on the second end wall 202. The explosion-proof valve can be a thinned portion or a notch, etc., arranged on the second end wall 202 of the cylindrical battery 21. The explosion-proof valve and the pole 212 are both far away from the heat exchanger 30, and the two are integrated in the end wall of the connecting manifold 40 of the cylindrical battery, so that when the explosion-proof valve explodes, the electrical connection between the valve-opening single battery and other single batteries or the electrical connection between the pole of the valve-opening single battery itself and the inside of the battery cell is disconnected.

[0055] The heat exchanger 30 is disposed on one side of the first end wall 201 of the cylindrical battery 21, the current collector 40 is disposed on one side of the second end wall 202 of the cylindrical battery 21, and the stopper 50 is disposed on one side of the peripheral wall 203 of the cylindrical battery 21. That is, the heat exchanger 30 is opposite to the first end wall 201 of the cylindrical battery 21, and the heat exchanger 30 is connected to the first end wall 201 of the cylindrical battery 21 (for example, abutting or connected by thermal conductive glue). The current collector 40 is opposite to the second end wall 202 of the cylindrical battery 21, and the current collector 40 is connected to the second end wall 202 of the cylindrical battery 21 (for example, welding). The stopper 50 is opposite to the peripheral wall 203 of the cylindrical battery 21, and the stopper 50 is connected to the peripheral wall 203 of the cylindrical battery 21 (for example, abutting or connected by connecting glue).

[0056] The heat exchanger 30 is a flat plate structure, and a flow channel is provided in the heat exchanger 30, and the flow channel is used to transmit the heat exchange medium. For example, the heat exchanger 30 is a heat exchange plate, and a medium channel is provided in the heat exchange plate, and the medium channel is used to transmit the heat exchange medium. A plurality of medium channels can be provided in the heat exchange plate, and the plurality of medium channels extend along the length direction of the heat exchange plate. The heat exchanger 30 with a flat plate structure has low processing difficulty, low cost, and high reliability.

[0057] The heat exchange plate may be a rectangular parallelepiped or a substantially rectangular parallelepiped structure, and may include two first surfaces disposed opposite to each other and a plurality of second surfaces disposed between the two first surfaces, wherein the area of ​​the first surface is greater than the area of ​​the second surface. The first surface of the heat exchange plate faces the first end wall 201 of the cylindrical battery 21, that is, the large surface of the heat exchange plate is the effective heat exchange surface. By setting the large surface of the heat exchange plate as the effective heat exchange surface, the heat exchange area is increased, thereby increasing the heat exchange efficiency and effectively suppressing the temperature rise of the battery device.

[0058] The heat exchange plate is thermally connected to the first end wall 201 of the cylindrical battery 21, and the first end wall 201 of the cylindrical battery 21 coincides with the first surface of the heat exchange plate, that is, the orthographic projection of the cylindrical battery 21 on the first surface of the heat exchange plate is located within the first surface. For example, the heat exchange plate and the second end surface of the cylindrical battery 21 are directly abutted. Alternatively, the heat exchange plate and the second end surface of the cylindrical battery 21 are connected by thermally conductive adhesive.

[0059] The battery pack may also include a liquid collecting pipe, which is connected to the heat exchange plate, and is used to provide cooling medium to the heat exchange plate and collect the heat exchange medium output by the heat exchange plate. When multiple heat exchange plates are provided in the battery pack, the liquid collecting pipe may be connected to multiple heat exchange plates.

[0060] The ratio of the area of ​​the first end wall 201 of the cylindrical battery 21 to the single cell capacity is in the range of 27mm 2 / Ah~130mm 2 / Ah. The heat exchanger 30 is thermally connected to the first end wall 201 of the cylindrical battery 21, that is, the cylindrical battery 21 dissipates heat through the first end wall 201. When the ratio of the area of ​​the first end wall 201 of the cylindrical battery 21 to the single cell capacity is in the range of 27mm 2 / Ah~130mm 2 / Ah, on the one hand, it ensures the capacity of the single battery, and on the other hand, it ensures that the battery can dissipate heat in time to avoid excessive battery temperature.

[0061] The busbar 40 may include a wiring harness plate, a busbar 41, a temperature detector and a circuit board. The wiring harness plate is disposed on the second end wall 202 of the cylindrical battery 21 and is opposite to the first end face of the cylindrical battery 21. The busbar 41 is disposed on the side of the wiring harness plate away from the cylindrical battery 21 (or the busbar 41 may be embedded in the wiring harness plate), and a connection hole is disposed on the wiring harness plate, and the cylindrical battery 21 is connected to the busbar 41 through the connection hole. The temperature detector may be disposed on the surface of the cylindrical battery 21 or the temperature detector may be disposed on the busbar 41, and the temperature detector is used to detect the temperature of the cylindrical battery 21. The circuit board is disposed on the side of the wiring harness plate away from the cylindrical battery 21, and the circuit board is connected to the temperature detector to transmit the temperature signal collected by the temperature detector.

[0062] The busbar 41 connects two adjacent cylindrical batteries 21 in the battery row 20. The busbar 41 may include a first busbar and a second busbar, the first busbar and the second busbar are connected, the first busbar is connected to the first battery, the second busbar is connected to the second battery, and the first battery and the second battery are two adjacent cylindrical batteries 21 in the battery row 20.

[0063] The busbar 41 connects adjacent cylindrical batteries 21 in the battery row 20 in series. When the two electrode ends of the cylindrical battery 21 are the pole 212 and the shell 211, respectively, the first busbar can be the shell 211 connection part, and the second busbar can be the pole 212 connection part. The first busbar connects the shell 211 of the first battery, and the second busbar connects the pole 212 of the second battery. When the two electrode ends of the cylindrical battery 21 are the first pole and the second pole, respectively, the first busbar connects the first pole of the first battery, and the second busbar connects the second pole of the second battery. Of course, in actual applications, the busbar 41 can also be connected in parallel to the cylindrical batteries 21 in the battery row 20, and the embodiments of the present disclosure are not limited to this.

[0064] The wiring harness board is an insulating board to achieve insulation between the busbar 41 and the cylindrical battery 21, and between the circuit board and the cylindrical battery 21. For example, the wiring harness board can be made of plastic, rubber or ceramic. The wiring harness board can be a plate-like structure, or the wiring harness board can also be a film structure. The circuit board can be a flexible circuit board (FPC) or a printed circuit board (PCB).

[0065] The temperature acquisition component may include a temperature transmission sheet and a temperature sensor. The temperature transmission sheet may be a nickel sheet. One end of the nickel sheet is connected to the housing 211 or the bus 41 of the cylindrical battery 21, and the other end of the nickel sheet is connected to the temperature sensor. The temperature sensor is provided on the circuit board. Alternatively, the temperature acquisition component may include a temperature sensor and a transmission harness. The temperature sensor is provided on the housing 211 or the bus 41 of the cylindrical battery 21. The temperature sensor is connected to the circuit board through the transmission harness, and the temperature signal is transmitted to the circuit board through the transmission harness.

[0066] The limiting member 50 is used to limit the battery. The limiting member 50 is provided with a plurality of accommodating parts, which are arc-shaped depressions, and the peripheral wall 203 of the cylindrical battery 21 is connected to the accommodating part. The accommodating part can be formed in the shape of the peripheral wall 203 of the cylindrical battery 21, and the cylindrical battery 21 is embedded in the accommodating part. For example, accommodating parts are respectively provided on both sides of the limiting member 50. The limiting member 50 is a metal part, which has a high structural strength, a small arc processing difficulty, and a high thermal conductivity coefficient, which is conducive to heat conduction.

[0067] In some possible implementations, such as Figure 4As shown, the limiting member 50 includes a main body 51 and an extension 52, the main body 51 is located between adjacent battery rows 20, and the extension 52 is provided at the end of the main body 51 along the direction of the battery row 20. The extension 52 is provided at both ends of the main body 51 along the direction of the battery row 20. For example, a first extension 52 and a second extension 52 are provided at both ends of the main body 51, respectively, the first extension 52 extends to a structural beam opposite to one end of the battery row 20, and the second extension 52 extends to a structural beam opposite to the other end of the battery row 20. That is, the extension 52 extends to the end beam, which is a structural beam located at the end of the battery row 20 along the direction of the battery row 20 among a plurality of structural beams.

[0068] For example, the battery pack includes a first battery layer, a second battery layer, and a stopper 50 disposed between the first battery layer and the second battery layer, and the extension portion 52 extends to the top surface of the end beam, and the top surface of the end beam is a side of the end beam away from the bottom plate 11. That is, the battery pack is composed of two layers of battery rows 20 and the stopper 50 between the two layers of battery rows 20.

[0069] On this basis, the height of the frame 12 can be consistent with the height of the battery row 20, so that the extension portion 52 extends in a direction parallel to the bottom plate 11 and can overlap the top surface of the end beam. The extension portion 52 extends to the top surface of the end beam, thereby shielding the gap between the battery row 20 and the end beam, thereby preventing metal impurities from falling into the gap between the battery row 20 and the end beam, and reducing the failure rate of the battery device.

[0070] When the extension part 52 is located on the top surface of the end beam and protrudes from the top surface of the end beam, the extension part 52 is easily damaged by collision with other components in the box body 10. To avoid this problem, a groove is provided on the top surface of the end beam, and the extension part 52 is embedded in the groove.

[0071] The depth of the groove may be consistent with the thickness of the extension 52, or the depth of the groove may be slightly less than the thickness of the extension 52. The depth of the groove is the dimension of the groove in a direction perpendicular to the bottom plate 11, and the thickness of the extension 52 is the dimension of the extension 52 in a direction perpendicular to the bottom plate 11.

[0072] Battery rows 20 are arranged on both the upper and lower sides of the main body 51. In order to achieve insulation between adjacent battery rows 20 and improve the safety of the battery device, the main body 51 is insulated from the two battery rows 20. The main body 51 can be made of insulating material, for example, the material of the main body 51 can be plastic, rubber or ceramic. Alternatively, an insulating layer can be provided on the surface of the main body 51 to achieve insulation between the main body 51 and the battery row 20.

[0073] For example, the main body 51 includes a supporting layer, a first insulating layer and a second insulating layer. The first insulating layer is disposed on a side of the supporting layer close to the bottom plate 11 , and the second insulating layer is disposed on a side of the supporting layer away from the bottom plate 11 .

[0074] The support layer may be a metal layer, for example, the material of the support layer may be stainless steel or aluminum alloy, etc. The support layer of the metal material ensures the strength of the support layer. The first insulating layer and the second insulating layer are respectively arranged on both sides of the main body 51, and the first insulating layer and the second insulating layer may be bonded to the support layer, or the first insulating layer and the second insulating layer may be coated on the support layer.

[0075] The cylindrical batteries 21 in the battery row 20 on both sides of the stopper 50 are respectively bonded to the stopper 50. For example, the first insulating layer is arranged on the side of the support layer away from the bottom plate 11, and the second insulating layer is arranged on the side of the support layer close to the bottom plate 11. The first battery layer is arranged on the side of the first insulating layer away from the support layer, and the second battery layer is arranged on the side of the second insulating layer away from the support layer. The cylindrical batteries 21 in the first battery layer are bonded to the first insulating layer, and the cylindrical batteries 21 in the second battery layer are bonded to the second insulating layer.

[0076] Optionally, the first insulating layer and the second insulating layer may be insulating adhesive layers, that is, the first insulating layer is used to both insulate the first battery layer and the support layer and to bond the first battery layer and the support layer. The second insulating layer is used to both insulate the second battery layer and the support layer and to bond the second battery layer and the support layer.

[0077] The extension portion 52 is connected to the support layer, and the extension portion 52 and the support layer are an integrally formed structure. It is worth noting that the first insulating layer and the second insulating layer in the embodiment of the present disclosure are not limited to covering only the support layer. In some embodiments, the first insulating layer and the second insulating layer may also cover the extension portion 52.

[0078] Optionally, the ratio of the thickness of the heat exchanger 30 to the length of the cylindrical battery 21 is in the range of 1 / 100 to 1 / 8, the thickness of the heat exchanger 30 is the dimension of the heat exchanger 30 along the axial direction, and the length of the cylindrical battery 21 is the dimension of the cylindrical battery 21 along the axial direction. The heat exchanger 30 is opposite to the first end wall 201 of the cylindrical battery. The longer the cylindrical battery is, the longer the axial heat transfer path in the single battery is. If the ratio of the thickness of the heat exchanger 30 to the length of the cylindrical battery 21 is too large, the heat exchanger 30 is too thick relative to the length of the cylindrical battery 21, and the temperature difference between the cylindrical battery 21 near the second end wall 202 and the temperature near the first end wall 201 will be too large, which is not conducive to the heat balance in the single battery; if the ratio of the thickness of the heat exchanger 30 to the length of the cylindrical battery 21 is too small, the heat exchanger 30 is too thin relative to the length of the cylindrical battery 21, the long heat exchanger 30 of the cylindrical battery is thin, and the cooling effect of the heat exchanger 30 on the long battery is insufficient. The heat exchange element 30 is a heat exchange plate, which has a flat plate structure.

[0079] The ratio of the thickness of the busbar 40 to the length of the cylindrical battery 21 ranges from 1 / 250 to 3 / 160, and the thickness of the busbar 40 is the dimension of the busbar 40 along the axial direction. If the ratio of the thickness of the busbar 40 to the length of the cylindrical battery 21 is too large, it means that the busbar 40 is too thick relative to the length of the cylindrical battery 21. Although the flow area is met, it is not conducive to the weight reduction and space utilization of the whole package; if the ratio of the thickness of the busbar 40 to the length of the cylindrical battery 21 is too small, it means that the busbar 40 is too thin relative to the length of the cylindrical battery, the flow effect is too poor and the busbar strength is insufficient. The vibration of multiple long batteries with different amplitudes along the battery axis direction pulls and tugs on the busbar 40, which can easily cause the busbar 40 to deform or even partially thin. The resistance of the thinned position is too large and overheating can easily cause thermal runaway. Among them, the busbar 40 can be a conductive bar.

[0080] The ratio of the thickness of the busbar 40 to the thickness of the heat exchanger 30 is in the range of 1 / 25 to 3 / 4. The busbar 40 and the heat exchanger 30 are arranged along the axial direction of the cylindrical battery 21. By setting the ratio of the thickness of the busbar 40 to the thickness of the heat exchanger 30 to the range of 1 / 25 to 3 / 4, the structural balance of the busbar 40 and the heat exchanger 30 is achieved, which can improve the space utilization and the flow and cooling effects.

[0081] The battery pack provided by the embodiment of the present disclosure includes a box body 10, a battery row 20, a heat exchanger 30, a current collector 40 and a stopper 50. The box body 10 has a bottom plate 11. The battery row 20 is arranged in the box body 10, and the axis of the cylindrical battery 21 in the battery row 20 is parallel to the bottom plate 11. The cylindrical battery 21 has a first end wall 201, a second end wall 202 and a peripheral wall 203 that are not coplanar. The heat exchanger 30 is arranged on one side of the first end wall 201 of the cylindrical battery 21, and the current collector 40 is arranged on the second end wall 202 of the cylindrical battery 21. 02, the limiting member 50 is arranged on one side of the peripheral wall 203 of the cylindrical battery 21, that is, the busbar 40 and the heat exchanger 30 are arranged on different sides of the cylindrical battery 21, which prevents the condensation on the heat exchanger 30 from flowing to the busbar 40, reducing the risk of short circuit of the battery pack, and the busbar 40 and the heat exchanger 30 are arranged on different sides, which solves the problem that the busbar 40 and the heat exchanger 30 on the same side will cause the metal busbar 40 to be subjected to repeated temperature differences, thereby causing metal fatigue and being unfavorable to improving the reliability of high-voltage connection. Furthermore, the heat exchanger 30, busbar 40 and limiting member 50 are respectively located on different sides of the cylindrical battery 21, avoiding the problem that the heat exchanger 30, busbar 40 and limiting member 50 interfere with each other when the battery pack is assembled. The limiter 50 and the busbar 40 are arranged on different sides, which solves the problem that when the limiter 50 and the busbar 40 are arranged on the same side, the limiter 50 needs to be made of insulating material due to the insulation requirement between the busbar 41 and the limiter 50, which leads to low strength of the limiter 50 (the strength of insulating materials is often lower than that of metal materials). The strength of the limiter 50 is improved, thereby improving the stability of the internal structure of the battery pack. The limiter 50 and the heat exchange plate are arranged on different sides, which solves the problem of poor structural stability of the battery pack caused by the heat exchange plate and the limiter 50 being arranged on the same side, thereby improving the structural stability of the battery pack. The axis of the cylindrical battery 21 is arranged parallel to the bottom plate 11, which can effectively reduce the height of the battery pack, thereby facilitating the control of the height dimension of the vehicle chassis.

[0082] The battery pack provided in the embodiment of the present disclosure can be applied to an electric vehicle. The battery pack is installed on the electric vehicle to provide energy to the electric vehicle. In practical applications, the battery pack can be installed on the frame of the electric vehicle. The battery pack can be fixedly connected to the frame. Alternatively, the battery pack can be a modular battery pack, which can be detachably connected to the vehicle body for easy replacement.

[0083] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A battery pack, characterized in that: The battery pack comprises: Box; At least one battery row, the battery row is arranged in the box, the battery row includes a plurality of cylindrical batteries arranged in sequence, the axis of the cylindrical battery is perpendicular to the arrangement direction of the battery, and the positive output terminal and the negative output terminal of the cylindrical battery are arranged on the same side of the cylindrical battery; A heat exchange element, the heat exchange element being used for exchanging heat with the battery; A busbar, the busbar being used to electrically connect a plurality of the cylindrical batteries; A limiting member, the limiting member is used to limit the battery in a direction perpendicular to the axis; Among them, the cylindrical battery has a first end wall and a second end wall that are arranged opposite to each other, and a peripheral wall located between the first end wall and the second end wall, the heat exchange component and the first end wall are arranged opposite to each other, the current collector and the second end wall are arranged opposite to each other, and the limit component and the peripheral wall are arranged opposite to each other.

2. The battery pack according to claim 1, characterized in that: The box body has a bottom plate, and the axis of the cylindrical battery is parallel to the bottom plate.

3. The battery pack according to claim 2, characterized in that: The cylindrical battery is a lithium iron phosphate battery, and the dimension of the cylindrical battery along the axis is greater than or equal to 60 mm.

4. The battery pack according to claim 2, characterized in that: The dimension of the cylindrical battery along the axis is L, the dimension of the battery pack along the height direction is H, the height direction is perpendicular to the bottom plate, and L>H.

5. The battery pack according to claim 1, wherein: The cylindrical battery is provided with an explosion-proof valve, and the explosion-proof valve is not provided on the first end wall of the cylindrical battery.

6. The battery pack according to claim 1, wherein: The pole and explosion-proof valve of the cylindrical battery are both arranged on the second end wall.

7. The battery pack according to claim 1, characterized in that: The limiting member is provided with a plurality of accommodating parts, the accommodating parts are arc-shaped depressions, and the peripheral wall of the cylindrical battery is connected to the accommodating parts.

8. The battery pack according to claim 1, wherein: The ratio of the area of ​​the first end wall of the cylindrical battery to the single cell capacity is in the range of 27mm 2 / Ah~130mm 2 / Ah.

9. The battery pack according to claim 1, characterized in that: The ratio of the thickness of the heat exchange element to the length of the cylindrical battery is in the range of 1 / 100 to 1 / 8, the thickness of the heat exchange element is the dimension of the heat exchange element along the axial direction, and the length of the cylindrical battery is the dimension of the cylindrical battery along the axial direction.

10. The battery pack according to claim 1, wherein: The ratio of the thickness of the busbar to the length of the cylindrical battery is in the range of 1 / 250 to 3 / 160, the thickness of the busbar is the dimension of the busbar along the axial direction, and the length of the cylindrical battery is the dimension of the cylindrical battery along the axial direction.

11. The battery pack according to claim 1, wherein: The ratio of the thickness of the collector to the thickness of the heat exchanger is in the range of 1 / 25 to 3 / 4, the thickness of the heat exchanger is the dimension of the heat exchanger along the axial direction, and the thickness of the collector is the dimension of the collector along the axial direction.

12. The battery pack according to claim 1, wherein: The heat exchange element is a flat plate structure, and a flow channel is arranged inside the heat exchange element, and the flow channel is used to transmit the heat exchange medium.

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