Battery pack for high-frequency pulse high-power discharge

Abstract

The invention provides a battery pack for high-frequency pulse high-power discharge. The battery pack comprises single batteries, the cable is used for connecting the single batteries; the cable comprises an integrated wire core and an external insulating layer, wherein the integrated wire core is composed of at least two strands of unit wire harnesses, and the external insulating layer is coated outside the integrated wire core. The method has the advantages that the number of unit wire harnesses is reasonably configured, the current change rate of each strand of wire harness during high-frequency discharge is effectively reduced, and therefore parasitic inductance in a loop is reduced; by adopting the corresponding shielding structure, the proximity effect influence among the multiple strands of unit wire harnesses is effectively reduced, the interference caused by high-frequency pulse discharge is reduced, and meanwhile, the antenna effect influence of a peripheral magnetic field on the battery pack connecting piece is prevented; after the internal shielding layer and the external shielding layer are communicated and grounded, a complete electromagnetic shielding system can be effectively formed, and the electromagnetic radiation of the battery pack during high-frequency pulse discharge and the sensitivity to an external electromagnetic field are remarkably reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of electric energy transmission anti-interference, and in particular relates to a battery pack for high-frequency pulse high-power discharge. Background Art

[0002] Battery packs are widely used as energy storage devices in electric vehicles, portable electronic devices, solar energy storage systems, military applications and many other fields to provide stable and continuous power for equipment. Pulse discharge technology is crucial in situations where instantaneous high power output is required, such as pacemakers and surgical instruments in the medical industry, laser processing, and military special equipment that requires high-frequency pulse working mode.

[0003] However, there are many difficulties in the high-frequency pulse discharge process of the battery pack. During high-frequency discharge, the high-frequency magnetic field of the peripheral circuit will affect the battery pack, and its internal connecting cables will receive the magnetic field to generate interference signals, interfering with the normal operation of electronic equipment such as the power management system. At the same time, the battery pack itself will generate strong electromagnetic radiation, which has potential effects on nearby electronic equipment, communication systems and human health. In addition, high-frequency pulse discharge causes the internal current of the battery pack to change sharply and generate a lot of heat. The reason is that the parasitic inductance in the line loop generates reverse electromotive force, which leads to a significant decrease in energy efficiency. In the existing battery pack design, copper bars, aluminum bars, and wires are used to directly connect the monomers or modules. These connectors are easy to absorb external electromagnetic waves to generate interference, and the internal parasitic inductance will also affect the energy efficiency during high-frequency and high-current discharge. Therefore, there is an urgent need for a battery pack that can adapt to high-frequency pulse discharge applications. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a battery pack for high-frequency pulse high-power discharge, which is particularly suitable for the scenario of high-frequency pulse discharge of the battery pack.

[0005] The technical solution adopted by the present invention is: in the first aspect, a battery pack for high-frequency pulse high-power discharge is provided, comprising:

[0006] Single battery;

[0007] A cable, used to connect the single batteries;

[0008] The cable comprises an integrated wire core composed of no less than two unit wire bundles and an external insulating layer, wherein the external insulating layer is coated on the outside of the integrated wire core.

[0009] Furthermore, the number of the unit wiring harnesses follows the equation I / n / t≤1×10 7 A / s, where I is the absolute value of the maximum discharge current of the battery pack, t is the rising or falling edge time requirement of the pulse discharge current, and n is the number of unit wiring harnesses.

[0010] Furthermore, the unit wiring harness comprises:

[0011] Unit core;

[0012] An internal first insulating layer, covering the outside of the unit wire core;

[0013] The internal shielding layer is coated on the outside of the internal first insulating layer.

[0014] Furthermore, it also includes an external shielding layer, which is coated on the outside of the integrated core, the external insulating layer is coated on the outside of the external shielding layer, and the internal shielding layer is connected to the external shielding layer.

[0015] Furthermore, the inner shielding layer and the outer shielding layer are grounded.

[0016] Furthermore, the unit wiring harness also includes an internal second insulating layer, which is coated on the outside of the internal shielding layer.

[0017] The advantages and positive effects of the present invention are as follows: due to the adoption of the above-mentioned technical scheme, by reasonably configuring the number of unit wiring harnesses, the current change rate of each wiring harness during high-frequency discharge is effectively reduced, thereby reducing the parasitic inductance in the loop; the corresponding shielding structure is adopted to effectively reduce the influence of the proximity effect between multiple unit wiring harnesses, reduce the interference caused by high-frequency pulse discharge, and prevent the external magnetic field from affecting the antenna effect of the battery pack connector, thereby improving the electromagnetic compatibility of the battery pack in a high-frequency pulse high-power discharge environment; the multi-layer insulation design is adopted to ensure the electrical insulation performance between the lines, ensure the safe and stable operation of the battery pack, and avoid short circuits and other faults caused by insulation problems; when the internal shielding layer and the external shielding layer are connected and grounded, a complete electromagnetic shielding system can be effectively formed, which can significantly reduce the electromagnetic radiation of the battery pack during high-frequency pulse discharge and its sensitivity to external electromagnetic fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a cable cross section according to an embodiment of the present invention

[0019] Figure 2 Schematic diagram of a cross section of a unit core according to an embodiment of the present invention

[0020] Figure 3 is a schematic diagram of a cable cross section of another embodiment of the present invention

[0021] Figure 4 Schematic diagram of a cross section of a unit core of another embodiment of the present invention

[0022] Figure 5 Schematic diagram of a battery pack discharge condition according to an embodiment of the present invention

[0023] In the figure:

[0024] 100, unit wire harness 110, unit wire core 120, internal first insulating layer

[0025] 130, internal shielding layer 140, internal second insulating layer 200, integrated core

[0026] 210, external insulation layer 220, external shielding layer DETAILED DESCRIPTION

[0027] The present disclosure is described more fully below with reference to the accompanying drawings, in which exemplary embodiments of the present disclosure are described. The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0028] like Figure 1 As shown, the present invention provides a battery pack for high-frequency pulse high-power discharge, comprising:

[0029] Single battery;

[0030] A cable, used to connect the single batteries;

[0031] The cable includes an integrated wire core 200 composed of at least two unit wire harnesses 100 and an external insulating layer 210 , wherein the external insulating layer 210 is coated on the outside of the integrated wire core 200 .

[0032] By using the above device, the single cells are connected in series or in parallel through cables. The single cells can also be equivalent to a battery module composed of multiple battery cells. The connection methods between the battery cells include but are not limited to welding connection, mechanical connection and flexible connecting sheet connection, and the battery modules are connected by cables. The cross-sectional style of the cable includes but is not limited to rectangular, triangular and circular. The unit wiring harness 100 adopts processes including but not limited to direct bonding, twisting and braiding to form the integrated wire core 200. The tightness between the unit wiring harnesses 100 should be moderate. Too tight may cause damage to the wiring harness, and too loose will affect the electrical performance and mechanical strength. The material of the external insulating layer 210 includes but is not limited to polyethylene (PE), polyvinyl chloride (PVC) or cross-linked polyethylene (XLPE). The coating method of the external insulating layer 210 on the integrated wire core 200 includes but is not limited to extrusion molding, injection molding and winding. The integrated wire core 200 composed of no less than two strands of unit wiring harnesses 100 effectively reduces the parasitic inductance during high-frequency pulse discharge. Reducing parasitic inductance can reduce the generation of reverse electromotive force, reduce the voltage drop of the battery pack during pulse discharge, improve the energy utilization efficiency and discharge stability of the battery pack, enable the battery pack to provide power to the equipment more efficiently, and extend the working time and service life of the equipment. Reasonable wiring and fixing methods can avoid mutual interference and displacement between wire harnesses, reduce performance degradation and safety hazards caused by factors such as electromagnetic interference and mechanical stress, and ensure stable operation of the battery pack under various working conditions.

[0033] In order to solve the problem of how to determine a reasonable number of unit wiring harnesses, an implementation method is provided in this embodiment.

[0034] In one embodiment, the number of unit harnesses 100 follows the equation I / n / t≤1×10 7 A / s, where I is the absolute value of the maximum discharge current of the battery pack, t is the rising or falling edge time requirement of the pulse discharge current, and n is the number of unit wiring harnesses 100.

[0035] By adopting the above device, the number of unit harnesses can be reasonably controlled to accurately adjust the current change rate of each harness during high-frequency pulse discharge, effectively suppressing the generation of parasitic inductance. This allows the battery pack to maintain a low energy loss and heat level during high-frequency pulse high-power discharge, improve the overall performance and reliability of the battery pack, and also help to extend the service life of the battery pack and reduce maintenance costs.

[0036] In order to solve the problem that the unit wiring harness has poor anti-electromagnetic interference capability, an implementation method is provided in this embodiment.

[0037] like Figure 2As shown, in one embodiment, the unit wire harness 100 includes: a unit wire core 110 ; an internal first insulating layer 120 , which is coated on the outside of the unit wire core 110 ; and an internal shielding layer 130 , which is coated on the outside of the internal first insulating layer 120 .

[0038] With the above device, the material of the unit wire core 110 includes but is not limited to copper, aluminum and aluminum alloy, and the internal first insulating layer 120 is used to isolate the unit wire core from the internal shielding layer 130 to prevent electrical short circuit. The material of the internal shielding layer 130 includes but is not limited to metal foil and braided metal mesh, which is used to reduce electromagnetic interference inside the unit wire harness.

[0039] In order to further reduce the problem of electromagnetic radiation and interference from external electromagnetic fields, an implementation method is provided in this embodiment.

[0040] like Figure 3 As shown, in one embodiment, it also includes an external shielding layer 220, which is coated on the outside of the integrated core 200, and the external insulating layer 210 is coated on the outside of the external shielding layer 220. The internal shielding layer 130 and the external shielding layer 220 are connected and grounded.

[0041] With the above device, the material and structure of the external shielding layer 220 are similar to those of the internal shielding layer 130, and are used to further reduce the electromagnetic radiation of the battery pack and prevent interference from external electromagnetic fields. The connection and grounding of the internal shielding layer 130 and the external shielding layer 220 are key measures to improve the electromagnetic compatibility of the battery pack. Connection points are set on the shielding layer or connecting pieces made of conductive materials are used to achieve connection.

[0042] In order to further reduce the problem of electromagnetic radiation and interference from external electromagnetic fields, an implementation method is provided in this embodiment.

[0043] In one embodiment, the inner shield layer 130 and the outer shield layer 220 are grounded.

[0044] By adopting the above device, after the internal shielding layer 130 and the external shielding layer 220 are connected and grounded, a complete electromagnetic shielding system can be effectively formed, which can significantly reduce the electromagnetic radiation of the battery pack during high-frequency pulse discharge and its sensitivity to external electromagnetic fields.

[0045] In order to further enhance the insulation performance of the unit wiring harness, an implementation method is provided in this embodiment.

[0046] like Figure 4 As shown, in one embodiment, the unit wire harness 100 further includes an internal second insulating layer 140 which is coated on the outside of the internal shielding layer 130 .

[0047] With the above device, the internal second insulating layer 140 is wrapped around the outside of the internal shielding layer 130 to further enhance the insulation performance of the unit harness, especially in some application scenarios with high insulation requirements, such as high-voltage battery packs or battery packs used in humid and corrosive environments.

[0048] The contents involved in the above embodiment are described below in conjunction with a preferred embodiment.

[0049] like Figure 5 As shown in the figure, the battery pack is composed of 144 single cells connected in series. Every 12 single cells are connected in series through cables to form a module, with a total of 12 modules. The modules are connected in series through cables. The working mode is pulse discharge, with a maximum current of 800A and a pulse rise time of 25μs. The operating voltage range of the battery pack is required to be 400V~600V. The fully charged voltage of the single cell is 4.16V, and the corresponding fully charged voltage of the battery pack is 599.04V. A single-core 70mm2 wire is used as the cable in series between modules, and a copper busbar with a cross-sectional size of 35mm×2mm is used for the connection between the single cells. When the battery pack is discharged, the voltage at the battery pack terminal drops to below 288V instantly, but the voltage of the single cell is still above 3.5V, indicating that the voltage drop caused by the polarization of the single cell in the battery pack is only (4.16-3.5)×144=95.04V. The voltage drop caused by the reverse electromotive force in the wire is 216V, which is the largest contributor to the overall voltage drop. Therefore, it is necessary to reduce the overall parasitic inductance of the battery pack and reduce the reverse electromotive force during pulse discharge. The copper bars connecting the cells are connected in parallel with multi-strand shielded copper bars with rectangular cross-sections, and the series cables between modules are changed to multi-strand shielded wires with circular cross-sections. The cross-sectional area of ​​a single core of the shielded cable is 10mm 2 The maximum current change rate in a single-strand shielded wire is 4.57×106 A. During pulse discharge, the instantaneous voltage drop of the battery pack is 150V, and the voltage drop contributed by the parasitic inductance in the wire is 54.96V.

[0050] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A battery pack for high-frequency pulse high-power discharge, characterized in that: include: Single battery; A cable, used to connect the single cells; The cable comprises an integrated wire core composed of no less than two unit wire bundles and an external insulating layer, wherein the external insulating layer is coated on the outside of the integrated wire core.

2. The battery pack for high-frequency pulse high-power discharge according to claim 1, characterized in that: The number of unit harnesses follows the equation I / n / t≤1×10 7 A / s, where I is the absolute value of the maximum discharge current of the battery pack, t is the rising or falling edge time requirement of the pulse discharge current, and n is the number of unit wiring harnesses.

3. The battery pack for high-frequency pulse high-power discharge according to claim 1, characterized in that: The unit wiring harness comprises: Unit core; An internal first insulating layer, covering the outside of the unit wire core; The internal shielding layer is coated on the outside of the internal first insulating layer.

4. The battery pack for high-frequency pulse high-power discharge according to claim 3, characterized in that: It also includes an external shielding layer, which is coated on the outside of the integrated core, the external insulating layer is coated on the outside of the external shielding layer, and the internal shielding layer is connected to the external shielding layer.

5. The battery pack for high-frequency pulse high-power discharge according to claim 4, characterized in that: The inner shield layer and the outer shield layer are grounded.

6. The battery pack for high-frequency pulse high-power discharge according to claim 3 or 4, characterized in that: The unit wire harness further includes an internal second insulating layer which is coated outside the internal shielding layer.

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