A battery cell heating device, a battery having the same, and a battery system

Abstract

The present invention provides a battery cell heating device, comprising a battery cell housing, and further comprising: an insulating layer, the insulating layer being disposed outside the battery cell housing; a receiving channel, the receiving channel comprising a positive electrode connection terminal, a negative electrode connection terminal, and a flow channel, the flow channel being disposed on the surface of the insulating layer in a circuitous manner and having at least two ends, the positive electrode connection terminal and the negative electrode connection terminal being located at different ends of the flow channel; a heating portion, the heating portion being a conductor, disposed within the receiving channel, and capable of forming a circuit between the heating portion and the positive and negative electrodes of the battery cell, the heating portion located at the positive electrode connection terminal conducting the positive electrode of the circuit, and the heating portion located at the negative electrode connection terminal conducting the negative electrode of the circuit; and a protective layer, the protective layer having insulating properties and covering the receiving channel. The present invention can simplify the battery heating device and reduce manufacturing and maintenance costs.

Description

Technical Field

[0001] The present invention relates to the field of power battery heating, and in particular to a battery core heating device and a battery and a battery system having the same. Background Art

[0002] In traditional processes, when it is necessary to heat the battery cells, the technical solutions adopted include: heating the coolant through a thermistor, and then allowing heat to be conducted between the coolant and the battery cells to heat the battery cells; or heating the coolant through a heat pump, and then allowing heat to be conducted between the coolant and the battery cells; or directly heating the battery cells with an external heating film.

[0003] Among them, the technical solution of heating the coolant for heat exchange requires the introduction of quite a number of components, such as heating devices, heat exchange devices, compressors, etc., and the coolant must be heated first so that the coolant flows through the pipeline before the battery cells can be heated by heat transfer. It has high costs, poor timeliness, low temperature regulation efficiency, and heating uniformity is easily affected by the coolant flow rate and is difficult to control.

[0004] In addition, the technical solution of directly heating the battery cell with an external heating film, the heating film and the battery cell are two independent components. This design usually attaches the heating film to the bottom or both sides of the entire battery for heating. It also has the disadvantages of long heat conduction distance, small heat exchange area, slow heating speed and large heating temperature difference. Summary of the Invention

[0005] The object of the present invention is to provide a battery cell heating device and a battery and a battery system having the same, so as to solve the shortcomings of the above technical solutions.

[0006] The present invention provides a battery core heating device, comprising a battery core housing and further comprising:

[0007] an insulating layer, the insulating layer being arranged outside the battery cell shell;

[0008] an accommodating channel, the accommodating channel comprising a positive electrode connecting end, a negative electrode connecting end, and a flow channel, the flow channel being circuitously disposed on the surface of the insulating layer and having at least two ends, the positive electrode connecting end and the negative electrode connecting end being located at different ends of the flow channel;

[0009] A heating part, which is a conductor and is disposed in the accommodating channel. A circuit can be formed between the heating part and the positive and negative electrodes of the battery cell. The heating part at the positive electrode connection end conducts the positive electrode of the circuit, and the heating part at the negative electrode connection end conducts the negative electrode of the circuit.

[0010] A protective layer is provided, wherein the protective layer has insulating properties and covers the accommodating channel.

[0011] Optionally, the positive electrode connection end or the negative electrode connection end passes through the insulating layer and is connected to the corresponding battery cell positive electrode or battery cell negative electrode.

[0012] Optionally, a connecting piece is also included, which is a conductor. The positive electrode connection end or the negative electrode connection end is provided with the connecting piece, and the connecting piece is connected to the heating part in the positive electrode connection end or the negative electrode connection end, and is connected to the positive electrode of the battery cell or the negative electrode of the battery cell.

[0013] Optionally, it also includes a connecting piece, which is a conductor. The connecting piece includes a positive connecting piece and a negative connecting piece. The positive connecting piece and the negative connecting piece are respectively fixedly connected to the heating parts in the positive connecting end and the negative connecting end, and are respectively connected to the positive electrode and the negative electrode of the battery cell.

[0014] Optionally, the battery cell casing is connected to either the positive electrode of the battery cell or the negative electrode of the battery cell. When the battery cell casing is connected to the positive electrode of the battery cell, a loop is formed between the heating part, the battery cell casing and the negative electrode of the battery cell. When the battery cell casing is connected to the negative electrode of the battery cell, a loop is formed between the heating part, the battery cell casing and the positive electrode of the battery cell.

[0015] Optionally, a switch is further included, and the switch turns on the heating part in the positive electrode connection end or the heating part in the negative electrode connection end.

[0016] Optionally, the total area of the heating portion is at least 40% of the total area of the battery cell shell, and the gap between the winding parts inside the flow channel is at least 1 mm.

[0017] Optionally, the battery cell housing is a rectangular parallelepiped, and more than 90% of the accommodating channels are arranged on the two surfaces with the largest areas in the rectangular parallelepiped; or the battery cell housing is a cylinder, and more than 90% of the accommodating channels are arranged on the side surfaces of the cylinder.

[0018] The present invention also provides a battery, comprising a battery cell having the battery cell heating device described in any one of the above technical solutions.

[0019] The present invention also provides a battery system, including a battery management system and a battery cell heating device according to any one of the above technical solutions, wherein the switch of the battery cell heating device is connected to the battery management system, and the battery management system can control the switch of any one of the battery cell heating devices.

[0020] In summary, the beneficial effects brought about by the present invention are:

[0021] 1. Simplified battery heating device, reducing manufacturing and maintenance costs;

[0022] 2. Reduce heat conduction distance, improve heating efficiency, and reduce energy loss during heating.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a general schematic diagram of a battery cell and a battery cell heating device provided in an embodiment of the present invention.

[0025] Figure 2 Schematic diagram of the accommodation channel provided in an embodiment of the present invention (without a connecting piece)

[0026] Figure 3 A schematic diagram of an accommodating channel provided in an embodiment of the present invention (with a connecting piece).

[0027] Figure 4 This is an electrical schematic diagram of battery module control provided by an embodiment of the present invention.

[0028] Description of Reference Numerals

[0029] 1-cell shell, 2-insulating layer, 3-accommodating channel, 31-flow channel, 32-positive electrode connection end, 33-negative electrode connection end, 4-heating part, 5-protective layer, 6-connecting piece, 61-positive electrode connection piece, 62-negative electrode connection piece, 7-switch, 8-collection harness. DETAILED DESCRIPTION

[0030] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0031] The term "conduction" in the description and claims of the present invention means that when describing that A conducts to B, A and B are part of a circuit, and when the circuit is supplied with electrical energy, current can pass between A and B.

[0032] like Figure 1-2 As shown, the battery cell heating device involved in this embodiment includes a battery cell housing 1, an insulating layer 2, a receiving channel 3, a heating portion 4, and a protective layer 5. The battery cell housing 1 is coated with an insulating layer 2, the receiving channel 3 is arranged on the surface of the insulating layer 2 in a circuitous manner, and the heating portion 4 is arranged within the receiving channel 3. The present invention heats the battery cell by forming a loop with the heating portion 4 on the surface of the insulating layer 2, and the heat dissipated by the loop when power is applied.

[0033] Specifically, the battery cell shell 1 is a rectangular aluminum shell with a thickness of 0.6 mm (not shown). Since there is a potential difference between the potential of the metal shell and the potential of the positive electrode of the battery cell, the metal shell will be corroded. Therefore, the structural design usually makes the metal shell conductive to either the positive or negative pole of the battery cell to eliminate the potential difference and avoid corrosion. In this embodiment, the positive pole of the battery cell is connected to the battery cell shell 1. The outside of the battery cell shell 1 is provided with an insulating layer 2 by spraying. The insulating layer 2 is an epoxy resin polymer with a thickness of 0.15 mm. Optionally, the insulating layer 2 can also be a ceramic polymer. Preferably, the thickness of the insulating layer 2 is selected in the range of 0.1 to 0.2 mm.

[0034] Specifically, the accommodating channel 3 is formed by etching or engraving before the battery cell housing 1 is assembled with the battery cell components such as the electrode sheet. The accommodating channel 3 includes a flow channel 31, a positive electrode connection terminal 32, and a negative electrode connection terminal 33. The flow channel 31 is arranged in a circuitous manner on the surface of the insulating layer, the positive electrode connection terminal 32 is located at one end of the flow channel 31, and the negative electrode connection terminal is located at the other end of the flow channel 31. In order to ensure the conductive area of the heating part 4 in the positive electrode connection terminal 32 and the negative electrode connection terminal 33, as shown in FIG. Figure 2 As shown, the positive and negative connecting ends have a local flow channel with the largest area in the entire accommodating channel 3 .

[0035] Optionally, the flow channel 31 may have more than two ends, in which case the positive electrode connection terminal 32 and the negative electrode connection terminal 33 are located at different ends of the flow channel 31. Of course, the positive electrode connection terminal 32 or the negative electrode connection terminal 33 may be located at the end of a single flow channel 31, or may include the ends of multiple flow channels 31 at the same time.

[0036] Specifically, since the cell housing 1 is a rectangular parallelepiped, the accommodating channel 3 is roughly U-shaped, and the flow channel 31 is arranged on the left and right surfaces of the cell housing 1. The flow channel 31 on the left surface leads to the right surface of the cell housing 1 by crossing the front surface. Figure 2 As shown, it is obvious that the flow channels 31 are mostly formed on the two surfaces with the largest areas in the battery cell shell 1, namely the left surface and the right surface. Specifically, more than 90% of the accommodating channels 3 are located on the two surfaces with the largest areas in the battery cell shell 1.

[0037] It should be noted that the design principle of this embodiment is to avoid arranging the accommodating channels 3 on the other four surfaces of the rectangular battery cell shell 1 as much as possible. The reason is that although the accommodating channels 3 can be arranged on the upper and lower surfaces of the rectangular battery cell shell 1, arranging the accommodating channels 3 on the upper surface requires avoiding components such as the positive and negative terminals. Since the lower surface has a smaller area, even if the accommodating channels 3 are arranged, it will not have a significant impact on the improvement of heat exchange efficiency. In addition, in the power battery assembly process, multiple battery cells need to be packaged together with the same outer shell frame to form a module. At this time, the front and rear surfaces of a single battery cell shell 1 need to be adhered to the module side panels for load-bearing and fixation. Therefore, if too many accommodating channels 3 are arranged on both sides of the rectangle, it will affect the structural fixation and height of the module, which is not worth the loss.

[0038] In an expanded manner, if the cell housing 1 is a cylinder, preferably, more than 90% of the accommodating channels 3 should be arranged on the side surfaces of the cylinder.

[0039] Specifically, in order to balance the relationship between the flow channel density and the space utilization of the shell, the gap between the winding parts of the flow channel 31 is at least 1 mm.

[0040] Specifically, the positive electrode connection terminal 32 penetrates the insulating layer 2 and is connected to the positive electrode of the battery cell, and the negative electrode connection terminal 33 does not penetrate the insulating layer 2, but is connected to the switch 7 (see Figure 4 ), the heating portion 4 deposited in the negative electrode connection terminal 33 is connected to the negative electrode of the battery cell through the switch 7.

[0041] Specifically, the heating part 4 arranged in the accommodating channel 3 is a conductor. Since the positive electrode connection terminal 32 passes through the insulating layer 2 and is connected to the positive electrode of the battery cell, the heating part 4 in the negative electrode connection terminal 33 is connected to the negative electrode of the battery cell through the switch 7. The heating part 4 forms a loop between the positive and negative electrodes of the battery cell through the accommodating channel 3. In this loop, the heating part 4 at the positive electrode connection terminal 32 is connected to the positive electrode of the loop, and the heating part 4 at the negative electrode connection terminal 33 is connected to the negative electrode of the loop. When the loop is closed and operated, the heating part 4 will dissipate heat according to its own resistance to heat the battery cell. In this embodiment, the heating part 4 is 0.05 mm thick copper, which is deposited in the accommodating channel 3 by physical vapor deposition. By extension, chemical vapor deposition or electroplating can also be used to deposit the heating part 4. The heating part 4 can also be made of conductive materials such as nickel or graphene.

[0042] Preferably, in order to ensure heating efficiency, the total area of the heating portion 4 is at least 40% of the total area of the battery cell housing 1 .

[0043] Optionally, the positive connection terminal 32 may not penetrate the insulating layer 2, but the heating portion 4 in the positive connection terminal 32 may be connected to the switch 7, and the positive electrode of the battery cell is turned on through the switch 7. At this time, the negative connection terminal 33 penetrates the insulating layer 2 and connects to the negative electrode of the battery cell.

[0044] Alternatively, as described above, the positive electrode connection terminal 32 may penetrate the insulating layer 2 and connect to the cell housing 1, so that the heating element 4 deposited in the positive electrode connection terminal 32 is indirectly connected to the positive electrode of the cell. In this case, the negative electrode connection terminal 33 does not penetrate the insulating layer 2, but is connected to the switch 7. The heating element 4 deposited in the negative electrode connection terminal 33 is connected to the negative electrode of the cell through the switch 7.

[0045] Specifically, when the cell housing 1 is connected to the negative electrode of the cell, the negative electrode connection terminal 33 can penetrate the insulating layer 2 and communicate with the cell housing 1, allowing the heating element 4 deposited in the negative electrode connection terminal 33 to indirectly achieve electrical connection with the negative electrode of the cell. In this case, the positive electrode connection terminal 32 does not penetrate the insulating layer 2, but is connected to the switch 7, allowing the heating element 4 deposited in the positive electrode connection terminal 32 to conduct electrical current to the positive electrode of the cell through the switch 7.

[0046] Preferably, in order to ensure the flow area at the positive and negative poles of the entire circuit, or to provide a platform for easy installation or connection of other components that may be attached, such as Figure 3 As shown, a connecting piece 6 as a conductor can also be provided on the positive and negative electrode connection ends. Specifically, the connecting piece 6 includes a positive electrode connecting piece 61 and a negative electrode connecting piece 62. The positive electrode connecting piece 61 is fixedly connected to the heating part 4 in the positive electrode connection end 32 and is connected to the positive electrode of the battery cell. The negative electrode connecting piece 62 is fixedly connected to the heating part 4 in the negative electrode connection end 33 and is connected to the switch 7 ( Figure 3 not shown), to achieve conduction with the negative electrode of the battery cell.

[0047] Furthermore, according to all the above solutions, the location where the positive and negative electrode connection terminals are fixedly connected to the positive and negative electrode connection sheets can be the location where the corresponding positive electrode connection terminal 32 or negative electrode connection terminal 33 penetrates the insulating layer 2. In addition, the positive and negative electrode connection terminals, the positive and negative electrode connection sheets, and the corresponding heating portions 4 in the positive and negative electrode connection terminals are fixedly connected, and the fixed connection means used can be spot welding, and the positive and negative electrode connection sheets can be electrode sheets.

[0048] Alternatively, in the above solution, a technical solution can be adopted in which a connecting piece 6 is provided at one end of the positive and negative electrode connection terminals and not at the other end. The purpose of designing the connecting piece 6 is to ensure the flow area and provide a platform for the fixed connection of possible additional components. If the flow channel 31 at the positive and negative electrode connection terminals is designed to have a larger area, whether to provide the connecting piece 6 and at which end the connecting piece 6 is provided can be flexibly determined by those skilled in the art as needed.

[0049] Specifically, the protective layer 5 is a 0.1 mm thick blue film made of polyester resin, which is dustproof and waterproof. The protective layer 5 covers the receiving channel 3, providing protection while also reducing overall heat loss in the circuit.

[0050] Furthermore, under the premise that the connecting piece 6 is provided, the protective layer 5 can also be provided to cover the connecting piece 6 to reduce additional insulation operation steps.

[0051] In addition, this embodiment also provides a battery system, including a battery management system (hereinafter referred to as BMS), and a collection harness 8. Figure 3 , a single cell has a cell heating device as described in any of the above solutions, and the negative electrode connecting piece 62 in each cell is connected to a switch 7, which serves as a switch of the cell heating device and is connected to the BMS (not shown). Figure 4 As shown, multiple switches 7 and corresponding data acquisition lines for multiple battery cells are gathered together through a data acquisition harness 8 and connected to the BMS in groups. This allows the BMS to control the switching of any battery cell heating device, thereby performing zoning management of the battery cells. When the BMS detects a heating demand, it controls the switch 7 to close, starting heating. After heating is complete, it turns off the heating.

[0052] Specifically, the switch 7 is a transistor switch, and the connection between the switch 7 and the battery core heating device can be completed by simply welding one pin of the transistor switch to the negative electrode connecting piece 62 .

[0053] It should be noted that by setting up multiple switches 7, it is also beneficial for the BMS to perform zoning management and balanced management of the battery cells. The balanced management here means that after multiple battery cells form a battery, each battery cell has a different position and a different heat exchange environment, and different power consumption characteristics will be generated between the battery cells. When several battery cells go through the same discharge scenario, some battery cells will have less remaining capacity. At this time, the BMS can be used to analyze each battery cell. If the remaining capacity of a battery cell after discharge becomes less than that of other battery cells, the BMS control management can be performed by controlling the switch 7. After reasonable wiring arrangement, the battery cells with more power are used to charge the battery cells with less power, ensuring the consistency of the battery cells and extending the battery life.

[0054] In summary, when the battery cell needs to be heated, the battery cell supplies power to the circuit formed by the heating part 4. The heating part 4 generates heat due to its own resistance while current flows through it. The heat acts on the battery cell shell 1 through the insulating layer 2, and finally heats the entire battery cell. It should be noted that the present invention is particularly suitable for heating battery cells under low temperature conditions. As is well known, the internal resistance and polarization of the battery cell increase under low temperature conditions, making it difficult to work normally for a long time. The circuit formed by the heating part only requires the battery cell to output a relatively small power to operate, and the heat it emits reacts to the battery cell, which can enable the battery cell to enter the temperature range where it can work normally as soon as possible, thereby reducing the impact of low-temperature discharge on the life of the battery cell.

[0055] In the above technical solution, by providing the heating portion 4 on the battery cell housing 1, the heating device and the battery cell are integrated. The present invention can bring the following beneficial effects:

[0056] 1. Simplify the battery heating device to reduce manufacturing and maintenance costs;

[0057] 2. Reduce heat conduction distance and improve heating efficiency.

[0058] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A battery cell heating device, comprising a battery cell housing, characterized in that: Also includes: An insulating layer, the insulating layer is arranged outside the battery cell shell for heat conduction; an accommodating channel, the accommodating channel includes a positive electrode connection end, a negative electrode connection end and a flow channel, the flow channel is arranged on the surface of the insulating layer in a circuitous manner and has at least two ends, the positive electrode connection end and the negative electrode connection end are located at different ends of the flow channel; a heating part, the heating part is a conductor, the heating part is arranged in the accommodating channel, a circuit can be formed between the heating part and the positive electrode and the negative electrode of the battery cell, the heating part located at the positive electrode connection end conducts the positive pole of the circuit, and the heating part located at the negative electrode connection end conducts the negative pole of the circuit; a protective layer, the protective layer has insulating properties and covers the accommodating channel, wherein the protective layer includes a blue film of polyester resin material.

2. The electric core heating device according to claim 1, characterized in that: The positive electrode connection end or the negative electrode connection end passes through the insulating layer and is connected to the corresponding battery cell positive electrode or battery cell negative electrode.

3. The electric core heating device according to claim 2, characterized in that: It also includes a connecting piece, which is a conductor. The positive electrode connecting end or the negative electrode connecting end is provided with the connecting piece. The connecting piece is connected to the heating part in the positive electrode connecting end or the negative electrode connecting end, and is connected to the positive electrode of the battery cell or the negative electrode of the battery cell.

4. The electric core heating device according to claim 1, characterized in that: It also includes a connecting piece, which is a conductor. The connecting piece includes a positive connecting piece and a negative connecting piece. The positive connecting piece and the negative connecting piece are respectively fixedly connected to the heating parts in the positive connecting end and the negative connecting end, and are respectively connected to the positive electrode and the negative electrode of the battery cell.

5. The electric core heating device according to claim 1, characterized in that: The battery cell shell is connected to either the positive electrode of the battery cell or the negative electrode of the battery cell. When the battery cell shell is connected to the positive electrode of the battery cell, a circuit is formed between the heating part, the battery cell shell and the negative electrode of the battery cell. When the battery cell shell is connected to the negative electrode of the battery cell, a circuit is formed between the heating part, the battery cell shell and the positive electrode of the battery cell.

6. The electric core heating device according to claim 1, characterized in that: The device further includes a switch, which turns on the heating portion in the positive electrode connection terminal or the heating portion in the negative electrode connection terminal.

7. The electric core heating device according to claim 1, characterized in that: The total area of the heating portion is at least 40% of the total area of the battery cell shell, and the gap between the winding parts inside the flow channel is at least 1 mm.

8. The electric core heating device according to claim 1, characterized in that: The battery cell shell is a rectangular parallelepiped, and more than 90% of the accommodating channels are arranged on the two surfaces with the largest areas of the rectangular parallelepiped; or the battery cell shell is a cylinder, and more than 90% of the accommodating channels are arranged on the side surfaces of the cylinder.

9. A battery, characterized in that: The invention comprises a battery cell having the battery cell heating device according to any one of claims 1 to 8.

10. A battery system, characterized in that: It comprises a battery management system and a cell heating device according to any one of claims 1 to 8, wherein the switch of the cell heating device is connected to the battery management system, and the battery management system can control the switch of any cell heating device.

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