Battery device and battery pack

Abstract

Battery device characterized in that it comprises a first battery set (1) and a second battery set (2) arranged adjacent to each other, wherein the first battery set (1) and the second battery set (2) each comprise at least two battery cells, wherein the current outputs of the at least two battery cells in the same battery set are electrically connected via a busbar (3), wherein the arrangement direction of the battery cells in the first battery set (1) is parallel to the arrangement direction of the battery cells in the second battery set (2), wherein the capacity of a single battery cell is defined as A, and the distance between the edge of the busbar (3) of the first battery set (1) and the edge of the busbar (3) of the second battery set (2) is defined as B, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm.

Description

TECHNICAL AREA

[0001] The invention relates to the technical field of new energy batteries, in particular to a battery device and a battery pack. BACKGROUND

[0002] With the continuous development of new energy technologies, batteries, as environmentally friendly devices for energy storage and release, are finding extensive applications in energy storage systems such as hydroelectric, thermal, wind and solar power plants, as well as in numerous technical fields such as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, aerospace, etc.

[0003] In the prior art, adjacent batteries in a battery pack are electrically connected via a busbar. During fast charging of the batteries at high C-rates, significant currents and voltages can occur in the busbar, leading to arcing short circuits between adjacent busbars. This compromises the overall insulation reliability of the battery pack and creates a risk of safety hazards such as short circuits that can lead to thermal runaway. DESCRIPTION OF THE INVENTION

[0004] Against this background, the present invention offers a battery device and a battery pack to solve the problem that busbars between adjacent battery sets in existing high-performance batteries are susceptible to arcing short circuits, thereby compromising battery safety.

[0005] In a first aspect, the present invention provides a battery device comprising a first battery set and a second battery set arranged adjacent to each other, wherein both the first battery set and the second battery set have at least two battery cells, wherein the current outputs of the at least two battery cells in the same battery set are electrically connected via a busbar, wherein the arrangement direction of the battery cells in the first battery set is parallel to the arrangement direction of the battery cells in the second battery set, wherein the capacity of a single battery cell is defined as A, and the distance between the edge of the busbar of the first battery set and the edge of the busbar of the second battery set is defined as B, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0006] Therefore, the advantage lies in the fact that, in the battery device according to the invention, the capacity of a single battery cell is defined as A, and the distance between the edge of the busbar of the first battery set and the edge of the busbar of the second battery set is defined as B, with the ratio of capacity A to distance B being 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm. Under this condition, sufficient current-carrying capacity of the busbar is ensured in addition to meeting the requirements for battery runtime. While the batteries are fast-charged at high C-rates, less heat is generated in the busbar. This makes arcing short circuits between the individual busbars less likely, thereby significantly reducing the risk of thermal runaway and improving battery safety. At the same time, the overall charging and discharging rate of the battery is ensured.

[0007] In a second aspect, the present invention further comprises a battery pack comprising a pack housing and a aforementioned battery device, wherein the battery device is arranged in the pack housing.

[0008] Since the battery pack according to the invention comprises the battery device according to the invention, it has the same advantageous effects as the battery device, which will not be described in detail here. DESCRIPTION OF THE DRAWINGS

[0009] To more clearly illustrate the technical solutions in the detailed embodiments of the present invention or the prior art, a brief introduction to the drawings necessary for describing the detailed embodiments or the prior art is given below. It should be noted that the accompanying drawings serve only to illustrate the embodiments of the invention. A person skilled in the art can obtain further drawings based on these accompanying drawings without any inventive step. Fig. Figure 1 schematically shows an overall view of the battery pack according to the invention; Fig. Figure 2 shows a side view of the battery pack according to the invention; Fig. Figure 3 shows a top view of the battery pack according to the invention; Fig. Figure 4a schematically shows an enlarged view of section C in relation to Fig. 3; Fig.Figure 4b schematically shows an enlarged view of section C' in relation to Fig. 3; Fig. Figure 5 schematically shows an enlarged view of section D in relation to Fig. 4a. Reference symbol list

[0010] 1. First battery set; 2. Second battery set; 3. Busbar; 4. Insulating element; 5. Housing; 6. Beveled structure; 7. Pack housing. DETAILED EXECUTION FORMS

[0011] To more clearly explain the objectives, technical features, and advantages of the embodiments of the present invention, the embodiments are described in detail below with reference to the accompanying drawings. However, the embodiments of the invention are not limited to these descriptions. All other embodiments that are achieved based on the present invention without inventive step are within the scope of protection of the present invention.

[0012] The exemplary embodiments of the battery device and the battery pack according to the invention are described below with reference to the Fig. 1, Fig. 2, Fig. 3, Fig. 4 to Fig. 5 described.

[0013] According to an embodiment of the present invention and in a first aspect, a battery device is provided comprising a first battery set 1 and a second battery set 2 arranged adjacent to each other, wherein the first battery set 1 and the second battery set 2 each have at least two battery cells, wherein the current outputs of the at least two battery cells in the same battery set are electrically connected via a busbar 3, wherein the arrangement direction of the battery cells in the first battery set 1 is parallel to the arrangement direction of the battery cells in the second battery set 2, wherein the capacity of a single battery cell is defined as A, and the distance between the edge of the busbar 3 of the first battery set 1 and the edge of the busbar 3 of the second battery set 2 is defined as B, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0014] Provided that the ratio of the capacity A of the individual battery cells to the distance B between the edge of the busbar 3 of the first battery set 1 and the edge of the busbar 3 of the second battery set 2 is satisfied, this battery device ensures sufficient current-carrying capacity of the busbar 3. During rapid charging of the batteries at high C-rates, less heat is generated in the busbar 3. This reduces the likelihood of arcing short circuits between the busbars 3, significantly decreasing the risk of thermal runaway and improving battery safety. At the same time, the overall charge and discharge rate of the battery is ensured. Furthermore, the distance B between the busbars 3 of adjacent battery sets can be determined based on the capacity A of the individual battery cells to achieve optimal space utilization within the battery sets.

[0015] As from Fig. 1 and Fig. As can be seen in Figure 2, the battery device, as one of the key components of the battery pack, serves to provide higher voltage and capacity to meet the power requirements of specific applications. The battery device comprises at least two battery sets. The number of battery sets to be used is selected depending on the power requirements. For example, the battery device may include two, three, four, five battery sets, etc. In this embodiment, the battery device comprises a first battery set 1 and a second battery set 2.

[0016] The first battery set 1 and the second battery set 2 each contain at least two battery cells. The number of battery cells to be used must be selected depending on the current requirements. For example, each battery set can comprise two, three, four, five battery cells, etc., with the individual battery cells forming a battery set through series or parallel connections.

[0017] The orientation of the battery cell in the first battery pack 1 is parallel to the orientation of the battery cell in the second battery pack 2. This means that the orientation of the main surface of the battery cell in the first battery pack 1 is parallel to the orientation of the main surface of the battery cell in the second battery pack 2. The orientation of the main surface of the battery cell is represented as a second direction, such as the arrow y in Fig. 4a and Fig.4b. The main area of ​​the battery cell refers to the largest side surface of a single battery cell.

[0018] The battery cell comprises a cell and a housing 5, the housing 5 comprising a shell body and a cover which are welded together to form a receiving space in which the cell is received. A cell is the smallest unit that can be charged and discharged separately and comprises a cell body and electrode tabs projecting from one end of the cell body, which are electrically connected to a current output arranged on the housing.

[0019] The components, such as the cell and electrolyte, are encapsulated within the casing of housing 5. The casing can be of various shapes and sizes, for example, rectangular, cylindrical, hexagonal, etc. Its design can be determined based on the cell's profile and size. The casing material can be diverse, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0020] The cover of housing 5 serves to close the opening in the shell body and to insulate the receiving chamber from the external environment. The shape of the cover can be adapted to the shape of the shell body to form the housing. The cover can be made of materials that possess a certain hardness and strength, for example, aluminum alloy.

[0021] The cell comprises a cell body, which includes a separator and two oppositely polarized electrode layers: a cathode layer and an anode layer. The cell body functions based on the movement of metal ions between the cathode and anode layers. The cell's charge-discharge cycle is the process by which the metal ions move from the cathode layer to the anode layer and then back again. The cell also includes electrode tabs that are electrically connected to the electrode layers. The positive electrode tab is connected to the cathode layer, and the negative electrode tab is connected to the anode layer, so that charging and discharging of the cell occur via the positive and negative electrode tabs. The electrode layer includes a current collector and an active material layer applied to the surface of the current collector.If the electrode layer is a cathode layer, the current collector can be made of aluminum, and the active material layer of lithium cobalt oxide, lithium iron phosphate, lithium nickel manganese cobalt oxide, or lithium manganese oxide, etc. If the electrode layer is an anode layer, the current collector can be made of copper, while the active material layer can be carbon, silicon, etc. The separator serves as an insulating layer to prevent internal battery short circuits caused by contact between the cathode and anode layers. Furthermore, the separator acts as a semipermeable layer to block larger molecules while allowing smaller charged ions to pass through.

[0022] The current output of the battery cell can be configured as the housing 5 or as a terminal. The terminal can be made of copper, aluminum, iron, stainless steel, aluminum alloy, nickel, etc. In the present embodiment, the terminal represents the current output of the battery cell.

[0023] In the same battery set, for example, in the first battery set 1, the current outputs of the at least two battery cells are electrically connected via a busbar 3, i.e., the terminals of the at least two battery cells are connected via a busbar 3. In the second battery set 2, the current outputs of the at least two battery cells are also electrically connected via a busbar 3, i.e., the terminals of the at least two battery cells are connected via a busbar 3. The busbar 3 serves to electrically connect the terminals of the at least two battery cells and can be made of copper, aluminum, iron, stainless steel, aluminum alloy, nickel, etc.

[0024] Busbar 3 collects the currents from the individual battery cells to create a uniform current output. This improves the efficiency of the battery system and optimizes the internal space allocation within the battery. Specifically, each battery cell is equipped with terminal connections. Busbar 3 is connected to the terminal connections of at least two adjacent battery cells, thus electrically connecting these two cells via busbar 3. For example, busbar 3 can electrically connect two, three, four, five, or any number of adjacent battery cells.

[0025] To reduce the risk of short circuits between adjacent battery sets, the busbars 3 for the adjacent battery sets are spaced apart, so that there is a gap between each busbar 3 for the adjacent battery sets. In this embodiment, the capacities of the battery cells are equal. The capacity of a battery cell is defined as A, and the distance between the edge of the busbar of the first battery set and the edge of the busbar of the second battery set is defined as B, where the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0026] Investigations suggest that the charging speed of the battery system should be increased to meet the requirements of high-voltage fast charging. Busbar 3 has a larger profile to ensure sufficient current carrying capacity, but this results in poor insulation between adjacent batteries. Particularly with larger capacities, the battery cells can generate a massive current and high voltage during high-voltage fast charging. This can lead to arcing short circuits, and potentially even thermal runaway, between the individual busbars of adjacent battery sets, significantly compromising battery safety.

[0027] Consequently, regulating the ratio of capacity A to distance B ensures sufficient current carrying capacity of busbar 3, in addition to meeting battery runtime requirements. During rapid charging of the batteries at high C-rates, less heat is generated in busbar 3. This reduces the likelihood of arcing between individual busbars 3, significantly lowering the risk of thermal runaway and improving battery safety. At the same time, the overall charging and discharging rate of the battery is ensured.

[0028] If the ratio of capacity A to distance B is too high, the risk of arcing short circuits between the individual busbars of adjacent battery sets and the risk of external short circuits between the battery sets are intensified, thereby impairing battery safety. Conversely, if the ratio of capacity A to distance B is too low, the batteries are subject to a slower charging rate during high-voltage rapid charging, thus impairing the functionality of the battery system.

[0029] In this embodiment, the ratio of capacity A to spacing B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm. Under these conditions, sufficient current-carrying capacity of the busbar is ensured, in addition to meeting the battery runtime requirements. While the batteries are fast-charged at high C-rates, less heat is generated in the busbar. This reduces the likelihood of arcing between individual busbars, significantly lowering the risk of thermal runaway and improving battery safety. At the same time, the overall charging and discharging rate of the battery is maintained.

[0030] In this embodiment, the ratio of the capacity A to the distance B can be either 3.3 Ah / mm or 3.5 Ah / mm, 5 Ah / mm, 20 Ah / mm, 65 Ah / mm, 93 Ah / mm, 110 Ah / mm or 150 Ah / mm, etc.

[0031] Furthermore, the capacity A of the battery cell is between 70 Ah and 720 Ah.

[0032] The capacity A of the battery cell can be determined according to practical electricity requirements. In this example, the capacity A of the battery cell lies between 70 Ah and 720 Ah. This capacity range is neither too large nor too small and can meet the requirements for battery runtime while also reducing the risk of thermal runaway.

[0033] For example, the capacity A of the battery cell can be 70 Ah, 90 Ah, 120 Ah, 250 Ah, 300 Ah, 688 Ah, 720 Ah, etc.

[0034] The capacity A of the battery cell should be neither too large nor too small. A battery cell with excessive capacity A generates a massive current and high voltage during high-voltage fast charging, which can easily lead to an arcing short circuit. Conversely, if the battery cell has insufficient capacity A, the battery life will be inadequate and the requirements for high-voltage fast charging will not be met.

[0035] In this embodiment, the capacity A of the battery cell is in the range of 70 Ah to 720 Ah. This capacity range is neither too large nor too small and does not result in excessive current or voltage during high-voltage fast charging. This reduces the risk of arcing and thermal runaway, ensures sufficient battery life, and also meets the requirements for high-voltage fast charging.

[0036] Furthermore, the distance B between the edge of the busbar 3 of the first battery set 1 and the edge of the busbar 3 of the second battery set 2 is between 4 mm and 22 mm.

[0037] The distance B between the edge of the busbar 3 of the first battery pack 1 and the edge of the busbar 3 of the second battery pack 2 can be determined according to the actual electrical demand and the internal dimensions of the battery pack. In this embodiment, the distance B between the edge of the busbar 3 of the first battery pack 1 and the edge of the busbar 3 of the second battery pack 2 is between 4 mm and 22 mm. This distance between the adjacent busbars 3 is neither too large nor too small and can not only ensure the current-carrying capacity of the busbars 3 but also prevent arcing short circuits.

[0038] For example, the distance B between the edge of busbar 3 of the first battery set 1 and the edge of busbar 3 of the second battery set 2 can be either 4 mm or 9 mm, 12 mm, 16 mm, 20 mm, 22 mm, etc.

[0039] The distance B between the edge of busbar 3 of the first battery set 1 and the edge of busbar 3 of the second battery set 2 should be neither too large nor too small. If the distance B is too large, the current-carrying capacity of busbar 3 is insufficient, causing it to generate excessive heat during fast charging at high charging rates. This increases the risk of thermal runaway for the batteries, impairs the charging / discharging rate, and reduces the space utilization of the battery device within the battery pack. If the distance B is too small, arcing and thermal runaway can occur between adjacent battery sets.

[0040] In this embodiment, the distance B between the edge of the busbar 3 of the first battery set 1 and the edge of the busbar 3 of the second battery set 2 is between 4 mm and 22 mm. This distance range B results in the busbar 3 having a better current-carrying capacity, generating less heat, and reducing the risk of thermal runaway. This ensures a reliable charge / discharge rate for the batteries and also increases the space utilization of the battery device within the battery pack, thus preventing arcing and improving battery safety.

[0041] Furthermore, the individual battery cells in the first battery set 1 are arranged in a first direction, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 145 Ah / mm.

[0042] The battery device comprises a first battery set 1 and a second battery set 2. As shown in Fig. As can be seen in 3 to 4b, the first battery set 1 and the second battery set 2 are each a battery set in the battery device.

[0043] As from Fig. 4a and Fig. As can be seen in Figure 4b, the direction of expansion of the main surface of the battery cells in the first battery set 1 is the direction shown by the arrow y, i.e., the second direction. As in Fig. 4a and Fig. As shown in 4b, the first direction is the direction indicated by the arrow x, i.e., a direction perpendicular to the second direction.

[0044] In this embodiment, the first battery assembly 1 comprises two battery cells arranged in the first direction. Here, the arrangement direction of the two battery cells is perpendicular to the second direction, i.e., perpendicular to the direction of extension of the main surface of the battery cells.

[0045] In this embodiment, the first battery pack 1 and the second battery pack 2 are arranged in the first direction as shown in Fig. 4a shows the arrangement where the ratio of capacity A to distance B is 3.3 Ah / mm ≤ A / B ≤ 140 Ah / mm. From the perspective in Fig. 4a The second battery set 2 is located to the right of the first battery set 1. During charging or discharging, the housing 5 of the battery cell can expand. In particular, the main surface of the battery cell can expand considerably outwards in the first direction, so that the distance between the adjacent battery sets, i.e., between the first battery set 1 and the second battery set 2, becomes smaller, and consequently the distance between the busbars 3 of the adjacent battery sets becomes too small. This creates a safety risk of short circuits.

[0046] By regulating the ratio of capacity A to distance B to 3.3 Ah / mm ≤ A / B ≤ 140 Ah / mm, i.e., by increasing the distance B between the edge of busbar 3 of the first battery bank 1 and the edge of busbar 3 of the second battery bank 2, the ratio of capacity A to distance B is limited, and a sufficient safety gap between the edge of busbar 3 of the first battery bank 1 and the edge of busbar 3 of the second battery bank 2 is ensured, even if the main area of ​​the battery cell is extended to a greater extent. This prevents arcing between the individual busbars, reduces the risk of thermal runaway, and improves battery safety.

[0047] In further embodiments, the first battery set 1 and the second battery set 2 are arranged in the second direction, wherein the ratio of the capacity A to the distance B is 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0048] As mentioned above, the first battery set 1 and the second battery set 2 each constitute a battery set in the battery device. The first battery set 1 and the second battery set 2 can be arranged differently, as long as the first battery set 1 and the second battery set 2 remain adjacent to each other. As shown above... Fig. As can be seen in 4b, the first battery pack 1 and the second battery pack 2 are arranged in the second direction. Starting from the perspective in Fig.4b the second battery set 2 is located below the first battery set 1. Here, the distance between the first battery set 1 and the second battery set 2 is relatively larger, so that it is comparatively less susceptible to contact between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2, where the ratio of the capacity A to the distance B is 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0049] Since the battery device comprises multiple battery sets, the number of second battery sets 2 arranged adjacent to the first battery set 1 is naturally not limited to one; the exact configuration depends on the specific position of the first battery set 1. As shown in the Fig. 3, Fig. 4a and Fig.As shown in 4b, in this embodiment the first battery set 1 is arranged adjacent to the second battery set 2 on its right side and also to the second battery set 2 below it.

[0050] Furthermore, the battery device comprises an insulating element 4, wherein the insulating element 4 is arranged between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2.

[0051] The busbar 3 of the first battery set 1 is spaced apart from the busbar 3 of the second battery set 2. Thus, a gap exists between the busbars 3 of the adjacent battery sets, with the insulating element 4 positioned in this gap between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2. The placement of the insulating element 4 increases the resistance between the busbars 3 of the adjacent battery sets and improves the insulation capacity of the busbar 3, thereby further reducing the risk of an arcing short circuit.

[0052] The insulating element 4 is made from insulating materials such as foamed silicone rubber, rubber, etc. Such an insulating element 4 not only has lower operating costs but also facilitates control of the overall manufacturing costs of the batteries. Furthermore, the lightweight foam material does not cause an excessive increase in the overall weight of the battery pack.

[0053] Furthermore, the specific resistance of the insulating element 4 is between 1×10 14 Ω·cm and 1×10 15 Ω·cm.

[0054] The insulating capacity of the insulating element 4 depends on its specific resistance. The higher the specific resistance, the better the insulating capacity of the insulating element 4. In this embodiment, the specific resistance of the insulating element 4 is between 1 × 10 14 Ω·cm and 1×10 15Ω·cm, so that the insulating element 4 has a standard-compliant insulation capacity without unnecessary production costs.

[0055] For example, the specific resistance of insulating element 4 can have values ​​of 1×10 14 Ω·cm or 4×10 14 Ω·cm, 6×10 14 Ω·cm, 1×10 15 Assume Ω·cm etc.

[0056] Furthermore, the ratio of capacity A to distance B is 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0057] In this embodiment, the arrangement of the insulating element 4 between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2 increases the insulation performance between the busbars 3 of the adjacent battery sets and reduces the risk of an arcing short circuit. Although the ratio of capacity A to distance B is limited to 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm, potential arcing short circuits and thermal runaway between the busbars 3 of the adjacent battery sets can nevertheless be avoided, and battery safety is improved.

[0058] Here, the ratio of capacity A to distance B can take the values ​​3.5 Ah / mm or 25 Ah / mm, 42 Ah / mm, 50 Ah / mm, 76 Ah / mm, 88 Ah / mm, 100 Ah / mm, 126 Ah / mm, 150 Ah / mm, etc.

[0059] Furthermore, the top of the insulating element 4 is higher than that of the busbar 3, or the top of the insulating element 4 is flush with the top of the busbar 3.

[0060] In the thickness direction of the battery pack (as in Fig. As shown in Figure 2, in the vertical direction (i.e., direction z), the top of the insulating element 4 is not lower than the top of the busbar 3, in order to enhance the insulation performance between the individual busbars 3 of adjacent battery sets. Therefore, the top of the insulating element 4 is either higher than that of the busbar 3, or the top of the insulating element 4 is flush with the top of the busbar 3. The choice can be made according to product requirements to increase the flexibility of the product design.

[0061] Furthermore, the top of the insulating element 4 is raised above the top of the busbar 3, the height by which the top of the insulating element 4 projects above the top of the busbar 3 being denoted by h, where 0.05 mm ≤ h ≤ 2 mm.

[0062] In this embodiment, the top surface of the insulating element 4 is located higher than the top surface of the busbar 3 in the thickness direction of the battery pack and can thus effectively increase the insulation performance between the busbars 3 of adjacent battery packs. In particular, the height by which the top surface of the insulating element 4 projects above the top surface of the busbar 3 is denoted as h, where 0.05 mm ≤ h ≤ 2 mm. For example, the height h can be 0.05 mm, 0.07 mm, 0.1 mm, 0.12 mm, 0.15 mm, 0.18 mm, 2 mm, etc.

[0063] The height h by which the top of the insulating element 4 projects above the top of the busbar 3 should be neither too large nor too small. If the height h is too large, i.e., the top of the insulating element 4 is significantly higher than the top of the busbar 3, this would cause the insulating element 4 to occupy a considerable amount of space in the thickness direction of the battery pack, thus reducing the space efficiency of the battery device. If the height h by which the top of the insulating element 4 projects above the top of the busbar 3 is too small, i.e., the top of the insulating element 4 is only slightly higher than the top of the busbar 3, the improvement in insulation between the busbars 3 of adjacent battery packs provided by the insulating element 4 is limited, resulting in generally inadequate prevention of arcing short circuits.

[0064] In this embodiment, the height h by which the top of the insulating element 4 projects above the top of the busbar 3 satisfies the condition 0.05 mm ≤ h ≤ 2 mm. This ensures that the height h by which the top of the insulating element 4 projects above the top of the busbar 3 is neither too large nor too small. The insulating element 4 does not occupy any significant space in the thickness direction of the battery pack and therefore does not impair the space efficiency of the battery device. Furthermore, the insulating element 4 effectively improves the insulation between the busbars 3 of adjacent battery packs and ensures that no arcing short circuits occur between the busbars 3 of adjacent battery packs.

[0065] Furthermore, the insulating element 4 is simultaneously partially arranged on the top side of the first battery set 1 and the second battery set 2.

[0066] As from Fig.4a and Fig. As shown in Figure 4b, the individual battery cell in the first battery pack 1 comprises a housing 5 arranged in the thickness direction of the battery pack, with the top surface of the housing 5 thus forming the top surface of the first battery pack 1. The individual battery cell in the second battery pack 2 also comprises a housing 5 arranged in the thickness direction of the battery pack, with its top surface forming the top surface of the second battery pack 2. In this configuration, the insulating element 4 not only provides increased insulation performance but also a reinforced structure between the adjacent battery packs. This improves the safety and reliability of the battery system.

[0067] The insulating element 4 is simultaneously partially arranged on the top side of the first battery pack 1 and the second battery pack 2. Optionally, the insulating element 4 can be attached to the top side of the first battery pack 1 and the second battery pack 2 by gluing, riveting, or similar methods. For example, the insulating element 4 can be glued to the battery cell housing 5 or to an upper insulating plate of the battery assembly.

[0068] Furthermore, the battery cell comprises a housing 5, wherein the top of the housing 5 has an exposed area on which the insulating element 4 is arranged.

[0069] The housing 5 is made of metal. As seen from Fig. 4a and Fig.As can be seen in Figure 4b, the top of the battery cell housing 5 is partially covered by the busbar 3, while the uncovered area of ​​the busbar 3 then represents the exposed area of ​​the top of the housing 5, on which the insulating element 4 is arranged. The insulating element 4 can either only partially cover this exposed area or it can completely cover this exposed area.

[0070] In the same battery pack, the busbar 3 serves to electrically connect the current outputs of at least two battery cells. In this embodiment, the current output represents a terminal connection, which means that the busbar 3 must not come into contact with the housing 5 of the battery cell to prevent a short circuit. By positioning the insulating element 4 on the exposed area of ​​the top of the housing 5, the insulation performance of the housing 5 is increased, the danger from contact between the busbar 3 and the housing 5 is avoided, and the safety of the battery device is improved.

[0071] Furthermore, the ratio of capacity A to distance B is 3.7 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0072] In this embodiment, the insulating element 4 is arranged on the exposed area of ​​the top of the housing 5. Although the ratio of the capacitance A to the distance B is limited to 3.7 Ah / mm ≤ A / B ≤ 150 Ah / mm, potential arcing short circuits and thermal runaway between the busbars 3 of adjacent battery sets can still be avoided, thus improving battery safety.

[0073] For example, the ratio of capacity A to distance B can take the values ​​3.7 Ah / mm or 15 Ah / mm, 28 Ah / mm, 41 Ah / mm, 62 Ah / mm, 78 Ah / mm, 85 Ah / mm, 90 Ah / mm, 125 Ah / mm, 140 Ah / mm, 150 Ah / mm, etc.

[0074] The insulating element 4 exhibits good high-temperature resistance, so that it does not melt under thermal stress if an arc occurs between the busbars 3 of adjacent battery sets. The insulating element 4 offers high stability and reliability in high-temperature environments and can therefore improve the insulation performance between the busbars 3 of adjacent battery sets.

[0075] Furthermore, the insulating element 4 partially covers the top of the busbar 3, wherein the overlap area between the insulating element 4 and the busbar 3 is S, where 200 mm 2 ≤ S ≤ 2600 mm 2 is.

[0076] In this embodiment, the insulating element 4 is not only arranged on the top of the battery cell housing 5, but also partially covers the top of the busbar 3 to prevent any contact and short circuits between the busbar 3 and the top cover of the battery pack, thus improving the safety and reliability of the battery pack. Furthermore, the insulating element 4 can further enhance the insulation performance between the busbars 3 of adjacent battery packs to reduce any arcing short circuits between them.

[0077] Starting from a bird's-eye view of the battery device (see also Fig.3) An overlap area exists between the insulating element 4 and the busbar 3, the area of ​​which corresponds to the area of ​​the top surface of the busbar 3 covered by the insulating element 4. The overlap area S between the insulating element 4 and the busbar 3 is 200 mm². 2 ≤ S ≤ 2600 mm 2 , for example at 200 mm 2 , 420 mm 2 , 650 mm 2 , 980 mm 2 , 1100 mm 2 , 1550 mm 2 , 1730 mm 2 , 1940 mm 2 , 2200 mm 2 , 2430 mm 2 or 2600mm 2 .

[0078] Furthermore, the ratio of capacity A to distance B is 4 Ah / mm ≤ A / B ≤ 150 Ah / mm.

[0079] In this embodiment, the insulating element 4 partially covers the top of the busbar 3, with the overlap area S being 200 mm. 2 ≤ S ≤ 2600 mm 2This increases the insulation performance between the busbars 3 of adjacent battery sets and reduces the risk of arcing. The ratio of the capacity A of the individual battery cell to the distance B between the busbars 3 of adjacent battery sets is 4 Ah / mm ≤ A / B ≤ 150 Ah / mm. The ratio of capacity A to distance B is further limited. Nevertheless, the occurrence of arcing between the busbars 3 of adjacent battery sets can still be prevented, thus avoiding thermal runaway and improving battery safety.

[0080] Here, the ratio of capacity A to distance B can take the value 4 Ah / mm or 10 Ah / mm, 22 Ah / mm, 49 Ah / mm, 60 Ah / mm, 85 Ah / mm, 110 Ah / mm, 125 Ah / mm, 143 Ah / mm, 150 Ah / mm.

[0081] Furthermore, the insulating element 4 is located between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2.

[0082] A gap is provided between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2. The insulating element 4 is positioned in this gap, such that both sides of the insulating element 4 abut an adjacent busbar 3 and cover the gap between the busbar 3 of the first battery set 1 and the busbar 3 of the second battery set 2. This allows the insulating element 4 not only to increase the insulation performance between the busbars 3 of the adjacent battery sets but also to limit the position of the busbars 3 on both sides of the insulating element 4 and also of the battery sets themselves. This prevents any displacement of the busbars 3 and the battery sets, thus improving the reliability of the internal battery structure.

[0083] In this embodiment, at least one side of the insulating element 4 is bonded to the busbar 3. For example, one side of the insulating element 4 can be bonded to one of the adjacent busbars, or both sides of the insulating element 4 can be bonded to the adjacent busbars. This ensures the stable positioning of the insulating element 4 and guarantees insulation between the adjacent busbars 3.

[0084] Furthermore, the capacity A of the battery cell is between 250 Ah and 400 Ah, while the ratio of capacity A to distance B is 11.5 Ah / mm ≤ A / B ≤ 64 Ah / mm.

[0085] In this embodiment, the battery cell has a larger capacity A to meet higher battery power demands. Specifically, the capacity A of the battery cell is between 250 Ah and 400 Ah, for example, 250 Ah, 300 Ah, 350 Ah, 380 Ah, or 400 Ah. Therefore, a further limitation of the ratio of capacity A to distance B is necessary. Here, the ratio of capacity A to distance B is 11.5 Ah / mm ≤ A / B ≤ 64 Ah / mm. This prevents arcing and thermal runaway between the busbars 3 of adjacent battery banks and improves battery safety. The distance B is between 6 mm and 22 mm, for example, 6 mm, 12 mm, 16 mm, or 22 mm, etc.

[0086] Accordingly, the ratio of capacity A to distance B can be 11.5 Ah / mm, 20 Ah / mm, 35 Ah / mm, 47 Ah / mm, 58 Ah / mm or 64 Ah / mm.

[0087] Furthermore, busbar 3 is provided with a reinforcement structure.

[0088] To increase the strength of busbar 3, a reinforcement structure is provided on busbar 3, provided that it does not excessively occupy the battery interior, in order to increase the overall structural strength of the battery device and to extend the service life of the battery device.

[0089] Specifically, the reinforcement structure includes at least one reinforcing rib that is arranged in the stacking direction of the battery pack.

[0090] Busbar 3 is provided with at least one reinforcing rib. The number of reinforcing ribs can be selected depending on the size of the busbar and the required structural strength. For example, busbar 3 is provided with one, two, three, or more reinforcing ribs.

[0091] In this embodiment, the reinforcing rib is arranged in the stacking direction of the battery pack. This increases the strength of busbar 3 and the overall robustness of the battery device, and avoids the problem of adjacent busbars being too close to each other due to battery expansion.

[0092] Furthermore, the busbar 3 is provided with a chamfered structure 6 at the corner of at least one side of the busbar 3.

[0093] As from Fig. 4a and Fig.As can be seen in Figure 5, the busbar 3 is provided with a chamfered structure 6 at the corner of at least one side. The chamfered structure 6 can be located at the corner of one side of the busbar 3 or at the corner of both sides of the busbar 3. Specifically, a chamfered structure 6 is formed at at least one corner on each of the opposite sides of the adjacent busbars 3 in order to increase the distance between the adjacent busbars 3 at this corner and to further prevent potential arcing short circuits between the adjacent busbars 3. The chamfered structures formed at the corner of the opposite sides of the adjacent busbars 3 can be identical or different in design.

[0094] In this exemplary embodiment with reference to Fig.5. Beveled structures 6 are provided at the corner of the opposite sides of the adjacent busbars 3, wherein the beveled structures at the corner of the opposite sides of the adjacent busbars 3 are designed differently, resulting in a more flexible structural arrangement. This ensures the current-carrying capacity of the busbars, increases the distance between the adjacent busbars 3 at the corner by means of the beveled structure, and prevents any potential arcing short circuit between the adjacent busbars 3.

[0095] Furthermore, the chamfered structure 6 represents a right-angled chamfer, wherein the length a of the right-angled side of the chamfered structure 6 is between 3 mm and 18 mm.

[0096] In this embodiment, the chamfered structure 6 can be formed much more easily as a right-angled chamfer. This can simplify the manufacturing process and creates a greater distance between the adjacent busbars to effectively prevent potential arcing short circuits. As shown in the figure below... Fig. As can be seen in Figure 5, a right-angled chamfer is formed at the corner of the right busbar 3. The length of the right-angled side of the chamfered structure 6 refers to the dimension of any right-angled side of the right-angled triangle formed by the busbar 3 and the exposed area of ​​the top of the battery cell housing 5 after the busbar 3 is positioned on the top of the housing 5.

[0097] Depending on the size of the busbar 3 and the battery power requirements, the length a of the right-angled side of the chamfered structure 6 can be between 3 mm and 18 mm. For example, the length a of the right-angled side of the chamfered structure 6 can be 3 mm, 6 mm, 10 mm, 12 mm, 15 mm, or 18 mm.

[0098] If the length a of the right-angled side of the beveled structure 6 is too large, more material must be removed from the corner of the busbar 3, thus impairing the current-carrying capacity of the individual busbars 3. If the length a of the right-angled side of the beveled structure 6 is too small, this has only a minor effect on increasing the distance between adjacent busbars, which is why arcing short circuits can occur more easily. In this embodiment, the length a of the right-angled side of the beveled structure 6 is between 3 mm and 18 mm. This length range can not only improve the current-carrying capacity of the individual busbar but also more effectively prevent potential arcing short circuits.

[0099] Furthermore, the chamfered structure 6 represents a rounding whose radius r lies between 1 mm and 8 mm.

[0100] In this embodiment, the chamfered structure 6 can also represent a rounding. This chamfered structure minimizes the number of cut edges at the corners of the busbar and thereby improves the current-carrying capacity of the busbar. As in Fig. As shown, the corners of the left busbar 3 have a rounded edge. Depending on the dimensions of busbar 3 and the specific battery power requirements, the radius r of the rounding can be between 1 mm and 8 mm. For example, the radius r of the rounding could be set to 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, or 8 mm.

[0101] If the radius r of the rounding is too large, more material is removed from the busbar 3 during machining, thus impairing its current-carrying capacity. If the radius r of the rounding is too small, arcing short circuits can occur more easily. In this embodiment, the radius r of the rounding lies between 1 mm and 8 mm. This radius range not only ensures the current-carrying capacity of the busbars but also more effectively prevents potential arcing short circuits.

[0102] This embodiment further provides a battery pack comprising a pack housing 7 and the battery device described in the aforementioned embodiment, wherein the battery device is arranged in the pack housing 7.

[0103] As from Fig. 1, Fig. 2 to Fig.As can be seen in Figure 3, the battery pack housing 7 has a rectangular shape, with the top of the housing 7 fitting together with the top cover. The housing 7 is provided with a base plate and a frame, the frame extending around the base plate and thus forming a receiving space. In this embodiment, the battery device is arranged in this receiving space. Naturally, the battery pack in this embodiment also includes the electrical components and structures that are common in existing battery packs (such as the battery management system), which will not be discussed in detail here.

[0104] In the battery pack, the capacity of a single battery cell is defined as A, and the distance between the edge of busbar 3 of the first battery set 1 and the edge of busbar 3 of the second battery set 2 is defined as B. The ratio of capacity A to distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm to ensure the battery pack achieves the required battery runtime and the current-carrying capacity of busbar 3 in the battery set. During rapid charging of the batteries at high charging rates, less heat is generated in busbar 3. This reduces the likelihood of arcing between busbars 3, significantly lowering the risk of thermal runaway and improving battery safety. At the same time, the overall charge and discharge rate of the battery is ensured.

[0105] The battery pack of this embodiment can be used in passenger cars, commercial vehicles and the like.

[0106] The following describes the measurement procedure for checking whether short circuits occur between the busbars 3 of the adjacent battery sets in the battery pack.

[0107] For the individual embodiments and comparative examples, 100 identical battery cells are used for testing, based on the capacity A shown in Table 1, and then divided into two battery sets, i.e., 50 battery cells per battery set. The output voltage of each cell is measured, and then the sum of the output voltages U1 of 100 battery cells is calculated. In each battery set, the busbar is welded to the current output of the battery cell. According to the spacing B in Table 1, 50 battery cells are connected in series, and then the two battery sets are connected in series to form a battery assembly. In the individual embodiments and comparative examples, all other specifications of the battery assembly are identical except for the capacity A and the spacing B.The output voltage U2 of the battery device is measured by electrically connecting the charging and discharging cables of the lithium battery charging and discharging cabinet to the positive and negative terminals of the battery device. The ratio of U2 to U1 is then calculated. If U2 / U1 ≥ 0.9, it is determined that there is no short circuit between the busbars. The test is rated as satisfactory. If U2 / U1 < 0.9, it is determined that there is a short circuit between the busbars. The test is rated as unsatisfactory. The capacity A of the battery cell and the distance B between adjacent busbars can be found in Table 1.

[0108] The following describes the test procedure for the charging time.

[0109] For the individual embodiments and comparative examples, 100 identical battery cells are used for testing, based on the capacity A shown in Table 1, and then divided into two battery sets, i.e., 50 battery cells per battery set. In each battery set, the busbar is welded to the current output of the battery cell. According to the spacing B in Table 1, 50 battery cells are connected in series, and then two battery sets are connected in series to form a battery assembly. In the individual embodiments and comparative examples, all other specifications of the battery assembly are identical except for the capacity A and the spacing B. The battery assembly is first discharged to 0% via ramp 1C, and then the charging time of the battery assembly from SOC 10% (state of charge) to SOC 80% via ramp 2.2C is measured.If the charging time exceeds 20 minutes, it is considered unsatisfactory. If the charging time is equal to or less than 20 minutes, it is considered satisfactory.

[0110] The following describes the test procedure with reference to the capacity A of the battery cell.

[0111] At 25 °C, the battery cell is charged via a 0.33C ramp to 100% state of charge (SOC) and then left to rest for one hour. The battery cell's capacity (A) is measured by electrically connecting the charging and discharging cables of the lithium battery charging and discharging cabinet to the positive and negative terminals of the battery cell. The battery cell is then discharged via a 0.33C ramp from 100% SOC to 0%, and the battery cell's capacity (A) is then determined. Table 1 A (Ah) B (mm) A / B (Ah / mm) Short circuit between the busbars? Charging time test Example 1 65 19,8 3,3 No in order Example 2 70 9 7,8 No in order Example 3 250 4 62,5 No in order Example 4 400 22 18,2 No in order Example 5 480 3,6 133,3 No in order Example 6 688 23,8 28,9 No in order Example 7 720 16 45,0 No in order Example 8 765 5,1 150,0 No in order Example 9 757 23,2 32,6 No in order Example 10 66 3,7 17,8 No in order Comparative example 1 54 18 3,0 No not ok Comparative example 2 757 4,8 158 Yes in order Comparative example 3 65 23,2 2,8 No not ok Comparative example 4 756 3,7 204,3 Yes in order

[0112] The measurements in the table above show that: In embodiments 1 to 10, the ratio of capacity A to distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm, with no short circuit occurring between the busbars and the charging duration test being rated as satisfactory. Consequently, sufficient current carrying capacity of the busbar can be ensured in addition to meeting the battery runtime requirements. While the batteries are fast-charged at high charging rates, less heat is generated in the busbar. Arcing short circuits between the busbars are unlikely, which significantly reduces the risk of thermal runaway and improves battery safety. At the same time, the overall charging and discharging rate of the battery is ensured.

[0113] In comparison examples 1 and 3, the charging time test was rated as unsatisfactory due to the insufficient ratio of capacity A to distance B. The charging speed is therefore too slow during high-voltage fast charging, which impairs the battery device's functionality.

[0114] In comparison examples 2 and 4, a short circuit occurs between the busbars due to the excessively large ratio of capacity A to distance B, which impairs battery safety.

[0115] Although embodiments of the present invention have been described with reference to the accompanying drawings, skilled persons may make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope defined by the accompanying claims.

[0116] The invention relates to the technical field of new and renewable energy batteries, in particular to a battery device and a battery pack, wherein the battery device can ensure sufficient current carrying capacity of the busbar while meeting the requirements for battery runtime, thereby generating less heat in the busbar while enabling rapid high-power charging of the batteries. The busbars are less susceptible to arcing short circuits, which significantly reduces the risk of thermal runaway and improves battery safety. At the same time, it ensures that the charging and discharging rates of the batteries remain completely constant.The embodiment according to the invention represents a battery device comprising a first battery set and a second battery set arranged adjacent to each other, wherein the first battery set and the second battery set each comprise at least two battery cells, and wherein the current outputs of the at least two battery cells in the same battery set are electrically connected via a busbar. The capacity of a battery cell is defined as A, and the distance from the edge of the busbar of the first battery set to the edge of the busbar of the second battery set is defined as B, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm.

Claims

Battery device characterized in that it comprises a first battery set (1) and a second battery set (2) arranged adjacent to each other, wherein the first battery set (1) and the second battery set (2) each comprise at least two battery cells, wherein the current outputs of the at least two battery cells in the same battery set are electrically connected via a busbar (3), wherein the arrangement direction of the battery cells in the first battery set (1) is parallel to the arrangement direction of the battery cells in the second battery set (2), wherein the capacity of a single battery cell is defined as A, and the distance between the edge of the busbar (3) of the first battery set (1) and the edge of the busbar (3) of the second battery set (2) is defined as B, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 150 Ah / mm. Battery device according to claim 1, characterized in that the individual battery cells in the first battery set (1) are arranged in a first direction, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 145 Ah / mm. Battery device according to claim 2, characterized in that the first battery set (1) and the second battery set (2) are arranged in the first direction, wherein the ratio of the capacity A to the distance B is 3.3 Ah / mm ≤ A / B ≤ 140 Ah / mm. Battery device according to claim 1, characterized in that the first battery set (1) and the second battery set (2) are arranged in a second direction, wherein the ratio of the capacity A to the distance B is 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm. Battery device according to claim 1, characterized in that an insulating element (4) is further provided, wherein the insulating element (4) is arranged between the busbar (3) of the first battery set (1) and the busbar (3) of the second battery set (2). Battery device according to claim 5, characterized in that the specific resistance of the insulating element (4) is in the range of 1×1014Ω·cm and 1×1015Ω·cm. Battery device according to claim 5, characterized in that the ratio of the capacity A to the distance B is 3.5 Ah / mm ≤ A / B ≤ 150 Ah / mm. Battery device according to claim 5, characterized in that the top of the insulating element (4) is higher than the top of the busbar (3), or the top of the insulating element (4) is flush with the top of the busbar (3). Battery device according to claim 8, characterized in that the top of the insulating element (4) is higher than the height h of the top of the busbar (3), wherein the height by which the top of the insulating element (4) projects above the top of the busbar (3) is h, where 0.05 mm ≤ h ≤ 2 mm. Battery device according to claim 5, characterized in that the insulating element (4) is simultaneously arranged partially on the top side of both the first battery set (1) and the second battery set (2). Battery device according to claim 10, characterized in that the battery cell comprises a housing (5) and an exposed area is formed on the top of the housing (5) on which the insulating element (4) is arranged. Battery device according to claim 11, characterized in that the ratio of the capacity A to the distance B is 3.7 Ah / mm ≤ A / B ≤ 150 Ah / mm. Battery device according to claim 5, characterized in that the insulating element (4) partially covers the top of the busbar (3), wherein the overlap area S between the insulating element (4) and the busbar (3) is at 200 mm2 ≤ S ≤ 2600 mm2. Battery device according to claim 13, characterized in that the ratio of the capacity A to the distance B is 4 Ah / mm ≤ A / B ≤ 150 Ah / mm. Battery device according to claim 5, characterized in that the insulating element (4) is located between the busbar (3) of the first battery set (1) and the busbar (3) of the second battery set (2). Battery device according to claim 1, characterized in that the capacity A of the battery cell is between 250 Ah and 400 Ah, whereby the ratio of the capacity A to the distance B is 11.5 Ah / mm ≤ A / B ≤ 64 Ah / mm. Battery device according to claim 1, characterized in that the busbar (3) is provided with a reinforcement structure. Battery device according to claim 17, characterized in that the reinforcement structure comprises at least one reinforcing rib, wherein the reinforcing rib extends in the stacking direction of the battery pack. Battery device according to one of claims 1 to 18, characterized in that a chamfered structure (6) is formed at the corner of at least one side of the busbar (3). Battery device according to claim 19, characterized in that the chamfered structure (6) represents a right-angled chamfer, wherein the length a of the right-angled side of the chamfered structure (6) is between 3 mm and 18 mm. Battery device according to claim 19, characterized in that the chamfered structure (6) represents a rounding, wherein the radius r of the rounding is between 1 mm and 8 mm. Battery device according to claim 1, characterized in that the capacity A of the battery cell is between 70 Ah and 720 Ah. Battery device according to claim 1, characterized in that the distance B between the edge of the busbar (3) of the first battery set (1) and the edge of the busbar (3) of the second battery set (2) is between 4 mm and 22 mm. Battery pack, characterized in that it comprises a pack housing (7) and a battery device according to one of claims 1 to 23, wherein the battery device is arranged in the pack housing (7).

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