Battery pack and powered device

Abstract

The present disclosure provides a battery pack and an electric device. The battery pack comprises a plurality of batteries, a box body, a heat insulation pad and a buffer. The plurality of batteries are arranged along a first direction. The box body is provided with a battery compartment for accommodating the plurality of batteries. The heat insulation pad is arranged between two adjacent batteries in the first direction. The buffer is arranged on one side of the heat insulation pad in the first direction. 1%≤C1%≤20%, 5%≤C2%≤90%, C1%<C2%, and 0.02W / (m·K)≤R≤0.2W / (m·K), wherein C1% is the compression rate of the heat insulation pad under 1Mpa pressure in the first direction, C2% is the compression rate of the buffer under 1Mpa pressure in the first direction, and R is the thermal conductivity of the heat insulation pad, with the unit of W / (m·K). In the present disclosure, the heat insulation pad has a low compression performance, so that the thickness of the heat insulation pad changes little and the heat insulation performance changes little during the whole life cycle of the battery, thereby improving the safety and reliability of the battery pack.

Description

Technical Field

[0001] This disclosure relates to the field of batteries, and more specifically to a battery pack and an electrical device having the battery pack. Background Technology

[0002] In a battery pack, thermal runaway can occur under abnormal conditions such as overheating or internal short circuits, releasing a large amount of heat instantaneously. This is the most serious safety malfunction in a battery system, causing the battery itself to bulge, catch fire, or even explode. When one battery experiences thermal runaway, it quickly spreads to adjacent batteries, leading to thermal runaway of the entire battery pack.

[0003] Traditionally, battery packs typically use thermal insulation pads between adjacent batteries. This allows the pads to effectively prevent the transfer of high temperatures to adjacent batteries in the event of thermal runaway, thus delaying or preventing the spread of thermal runaway throughout the battery pack. However, batteries expand during cyclic use, continuously compressing the thermal insulation pads, causing them to thin and their insulation performance to deteriorate. This results in the pads failing to adequately protect the batteries adjacent to them, ultimately leading to thermal runaway of the entire battery pack. Utility Model Content

[0004] In view of this, the present disclosure provides a battery pack to at least solve or improve the problem that the thermal insulation performance of the thermal insulation pad is reduced due to the compression of the thermal insulation pad by the battery cycle expansion in conventional battery packs.

[0005] The battery pack includes multiple batteries, a housing, a heat insulation pad, and a cushioning element. The multiple batteries are arranged along a first direction. The housing contains a battery compartment for storing the multiple batteries. The heat insulation pad is positioned between two adjacent batteries in the first direction. The cushioning element is positioned on one side of the heat insulation pad in the first direction. 1%≤C1%≤20%, 5%≤C2%≤90%, C1%<C2%, and 0.02W / (m·K)≤R≤0.2W / (m·K), where C1% is the compressibility of the heat insulation pad under 1 MPa pressure in the first direction, C2% is the compressibility of the cushioning element under 1 MPa pressure in the first direction, and R is the thermal conductivity of the heat insulation pad, in W / (m·K).

[0006] In this disclosure, by reducing the compressibility of the heat insulation pad, it is less susceptible to compression and deformation during battery cyclic expansion, thereby reducing its thickness variation throughout the battery lifespan. This effectively avoids the problem of reduced heat insulation performance caused by a thinner heat insulation pad, ensuring that the heat insulation performance of the pad remains stable throughout the battery lifespan. This, in turn, ensures that the heat insulation pad effectively suppresses heat spread throughout the battery lifespan, significantly improving the safety and reliability of the battery pack. Furthermore, since the battery expands in volume during charging and discharging, it exerts continuous pressure on the surrounding structure. The buffer component, through its compressibility, provides the necessary expansion space for the battery. This effectively prevents mechanical damage or deformation of the battery itself or the casing due to excessive expansion forces.

[0007] This disclosure also provides an electrical device that includes the aforementioned battery pack. Attached Figure Description

[0008] It should be understood that the following figures only illustrate certain embodiments of this disclosure and should not be construed as limiting the scope.

[0009] It should be understood that the same or similar reference numerals are used in the accompanying drawings to denote the same or similar elements.

[0010] It should be understood that the accompanying drawings are only schematic, and the dimensions and scales of the elements in the drawings are not necessarily precise.

[0011] Figure 1 This is a schematic cross-sectional view of a battery pack according to an embodiment of the present disclosure.

[0012] Figure 2 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning components.

[0013] Figure 3 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0014] Figure 4 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0015] Figure 5 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0016] Figure 6 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0017] Figure 7 for Figure 1A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0018] Figure 8 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0019] Figure 9 for Figure 1 A schematic diagram of the structure of the battery, heat insulation pad, and cushioning component in another embodiment.

[0020] Figure 10 This is a schematic diagram of the structure of an electrical device according to an embodiment of the present disclosure.

[0021] Figure Labels Battery pack - 100; Battery - 10; Box - 20; Battery compartment - 21; Electrical compartment - 22; Separator beam - 23; Top cover - 30; Heat insulation pad - 40; Buffer - 50; Bottom strip - 51; Side strip - 52; Top strip - 53; Strip - 54, 55; Buffer pad - 56; Electrical equipment - 200. Detailed Implementation

[0022] Numerous specific details are set forth below to provide an understanding of the structure, function, and use of the embodiments described and illustrated in the specification and figures. It is to be understood that the embodiments described and illustrated herein are non-limiting examples, and thus it will be appreciated that the particular structural and functional details disclosed herein are representative and exemplary. Variations and changes may be made to these embodiments without departing from the scope of the claims.

[0023] <Example Battery Pack> refer to Figure 1 According to one embodiment of this disclosure, a battery pack 100 may include a battery group composed of multiple batteries connected in series and parallel, and integrate a battery management system (BMS), a thermal management system, an electrical connection system (high-voltage / low-voltage connectors, wiring harnesses, etc.), structural components (casing, brackets, etc.), and protective components. The battery pack 100 may also include a housing 20, in which the aforementioned components are housed and sealed by a top cover 30, forming a complete functional unit capable of directly outputting electrical energy. The battery pack 100 can serve as a rechargeable battery and a power source for new energy vehicles, primarily used for storing and providing electrical energy.

[0024] The top cover is located on the top side of the enclosure and forms a storage cavity with the enclosure. A partition beam 23 is provided inside the enclosure 20, dividing the storage cavity into a battery compartment 21 and an electrical compartment 22. Multiple batteries 10 are stored in the battery compartment 21, while the electrical compartment 22 is used to store other components such as the BMS. The enclosure 20 effectively prevents external collisions, compression, and vibrations from affecting the multiple batteries 10 and other components such as the BMS inside the enclosure 20. Furthermore, the enclosure 20 also prevents external moisture or dust and other contaminants from entering the interior of the enclosure 20.

[0025] A battery pack can be formed by connecting multiple batteries 10 with similar capacity and internal resistance. For example, multiple batteries 10 can be connected in series to form a battery pack, or multiple batteries 10 can be connected in parallel to form a battery pack, or a portion of multiple batteries 10 can be connected in series and another portion can be connected in parallel to form a battery pack.

[0026] The battery pack 100 may also include conductive elements. The conductive elements can electrically connect the terminals of at least two batteries 10, i.e., the output terminals of the battery current, to enable multiple batteries 10 to be connected in series or in parallel.

[0027] Battery 10 is the basic energy storage unit in the battery pack, used to store and release electrical energy, and capable of converting chemical energy into electrical energy (discharging process) or storing electrical energy as chemical energy (charging process) through internal chemical reactions. During charging and discharging, battery 10 undergoes a certain volume expansion and contraction. In battery pack 100, multiple batteries 10 are arranged along a first direction. Multiple batteries 10 can be electrically connected in series or parallel to meet different voltage, capacity, and power requirements. In some embodiments, battery 10 is a prismatic battery. In other embodiments, battery 10 is a cylindrical battery. In other embodiments, battery 10 is a pouch battery. In other embodiments, battery 10 may also be other types of batteries. This disclosure does not limit its type. For ease of description, X is used to indicate the first direction in the accompanying drawings of this disclosure.

[0028] Under abnormal conditions, battery pack 100 may experience thermal runaway, which is a phenomenon where an exothermic reaction occurs inside the battery due to short circuits, overcharging, or high temperatures, causing the temperature to rise rapidly and become uncontrollable. Thermal runaway not only damages the battery but can also lead to safety accidents. When one battery experiences thermal runaway, it quickly spreads to adjacent batteries, causing the entire battery pack to experience thermal runaway.

[0029] The battery pack 100 may further include a heat insulation pad 40, which is disposed between two adjacent batteries 10 in the first direction. When a battery 10 experiences thermal runaway, the heat insulation pad 40, through its own heat insulation performance, can effectively block the transfer of high temperature to adjacent batteries 10, thereby delaying or preventing the spread of thermal runaway throughout the battery pack 100. The compressibility C1% of the heat insulation pad 40 under a pressure of 1 MPa in the first direction satisfies: 1% ≤ C1% ≤ 20%. Preferably, 5% ≤ C1% ≤ 15%. More preferably, 9% ≤ C1% ≤ 11%. Alternatively, the compressibility C1% of the heat insulation pad under a pressure of 1 MPa in the first direction may also be 3%, 7%, 13%, or 18%. The thermal conductivity R (in W / (m·K)) of the heat insulation pad 40 satisfies: 0.02 W / (m·K) ≤ R ≤ 0.2 W / (m·K). Preferably, 0.06 W / (m·K) ≤ R ≤ 0.16 W / (m·K). More preferably, 0.1 W / (m·K) ≤ R ≤ 0.12 W / (m·K). Alternatively, the thermal conductivity R of the heat insulation pad 40 can also be 0.04 W / (m·K), 0.08 W / (m·K), 0.14 W / (m·K), or 0.18 W / (m·K). In some embodiments, the heat insulation pad 40 is a nanoplate. A nanoplate (also called a nanocomposite plate or nano-insulation plate) is a heat insulation material that uses nanoporous materials (such as nanoscale aerogels) as the main functional material and is composited with reinforcing materials through a special process. By way of example only, the nanoplate can be one or more of glass fiber, silica aerogel or fumed silica, titanium dioxide, or silicon carbide. For example, a nanoplate can be prepared by uniformly mixing aerogel, glass fiber, and a light-blocking agent and then pressing them together. It should be noted that the nanoplates and the technologies used in the nanoplates mentioned in this disclosure are well known to those skilled in the art.

[0030] If the compression ratio C1% of the heat insulation pad 40 under a pressure of 1 MPa in the first direction is too high, the heat insulation pad 40 is prone to deformation after being subjected to pressure. After the battery 10 cyclically expands and compresses the heat insulation pad 40, the heat insulation pad 40 is easily permanently compressed, reducing its thickness and making it impossible to return to its initial thickness. This results in a decrease in heat insulation performance, which means that it cannot effectively block heat transfer during thermal runaway of the battery 10, leading to thermal runaway of the entire battery pack 100. If the compression ratio C1% of the heat insulation pad 40 under a pressure of 1 MPa in the first direction is too low, the heat insulation pad 40 is too rigid and difficult to compress, failing to provide expansion space for the battery 10. When the battery 10 expands, it will compress the rigid heat insulation pad, generating mechanical stress, which may cause damage to the battery casing or internal components, thereby affecting the service life and safety performance of the battery 10. Within the reasonable range of 1%≤C1%≤20%, it can be ensured that the thickness of the heat insulation pad 40 changes little throughout the entire battery life cycle, and the heat insulation performance is less affected by the battery cycle expansion and compression, so that the heat insulation pad 40 can effectively block the transfer of heat throughout the entire battery life cycle.

[0031] If the thermal conductivity R of the heat insulation pad 40 is too high, it indicates that the heat insulation pad 40 has good thermal conductivity, meaning that its thermal insulation performance is poor. When a battery experiences thermal runaway, heat will be rapidly transferred to adjacent batteries through the heat insulation pad 40, leading to thermal runaway of the entire battery pack 100. If the thermal conductivity R of the heat insulation pad 40 is too low, it will reduce the mechanical strength of the heat insulation pad 40 and increase the difficulty of the manufacturing process. Within the range of 0.02 W / (m·K) ≤ R ≤ 0.2 W / (m·K), the heat insulation pad 40 has good thermal insulation performance and also good mechanical strength.

[0032] The battery pack 100 may further include a buffer 50 disposed on one side of the heat insulation pad 40 in the first direction. The buffer 50 provides expansion space for the battery 10. The compression ratio C2 of the buffer 50 under a pressure of 1 MPa in the first direction satisfies: 5% ≤ C2% ≤ 90%, and C1% < C2%. Preferably, 15% ≤ C2% ≤ 80%, more preferably, 25% ≤ C2% ≤ 70%. Alternatively, the compression ratio C2% of the buffer under a pressure of 1 MPa in the first direction may also be 10%, 35%, 45%, 55%, or 65%. In some embodiments, the buffer may be made of solid silicone rubber. In other embodiments, the buffer 50 may also be made of MPP (microcellular polypropylene foam). In other embodiments, the buffer 50 may also be made of other materials. This disclosure does not limit the material.

[0033] If the compression ratio C2% of the buffer 50 under a pressure of 1 MPa in the first direction is too large, the buffer 50 will be too soft. During the cyclic expansion and compression of the battery, the buffer 50 will be easily over-compressed and unable to provide a cushioning effect. If the compression ratio C2% of the buffer 50 under a pressure of 1 MPa in the first direction is too small, the buffer 50 will be too rigid and unable to provide expansion space for the battery 10. Within a reasonable range of 5% ≤ C2% ≤ 90%, the buffer 50 can absorb the expansion force of the battery through its own compressibility, providing sufficient expansion space for the battery 10. At the same time, the buffer 50 has sufficient rebound force after being compressed.

[0034] According to the battery pack 100 constructed as described above, the heat insulation pad 40 has low compressibility, making it less prone to compression and deformation during battery cycle expansion, thereby reducing its thickness variation throughout the battery lifespan. This effectively avoids the problem of reduced heat insulation performance due to thinning of the heat insulation pad, ensuring that the heat insulation performance of the heat insulation pad 40 remains stable throughout the battery lifespan. This, in turn, ensures that the heat insulation pad 40 effectively suppresses heat spread throughout the battery lifespan, significantly improving the safety and reliability of the battery pack 100. Furthermore, since the battery 10 expands in volume during charging and discharging, it exerts continuous pressure on the surrounding structure. The buffer 50, through its own compressibility, provides the necessary expansion space for the battery 10. This effectively prevents mechanical damage or deformation of the battery itself or the casing due to excessive expansion force.

[0035] In another embodiment, the large surfaces of two adjacent batteries face each other, with 1% ≤ C1% ≤ 17%, 5% ≤ C2% ≤ 88%, and C1% < C2%. Preferably, 3% ≤ C1% ≤ 14%, 23% ≤ C2% ≤ 70%, more preferably, 6% ≤ C1% ≤ 10%, 33% ≤ C2% ≤ 50%. Alternatively, C1% can also be 11%, 13%, or 16%, and C2% can also be 13%, 67%, or 77%.

[0036] Battery expansion is caused by the production of gas from internal chemical reactions, leading to increased pressure. When the battery expands, the central portion of the large surface area is structurally weaker and lacks sufficient support to resist this outward force. Therefore, the expansion of the large surface area is more pronounced compared to the edges and sides of the battery, resulting in greater expansion forces on the heat insulation pad 40 and the buffer 50. To ensure that the heat insulation pad 40 maintains good thermal insulation performance throughout the battery's lifespan, and that the buffer 50 provides sufficient restraint to prevent excessive expansion of the large surface area, the compression ratio C1% of the heat insulation pad 40 under 1 MPa pressure in the first direction and the compression ratio C2% of the buffer 50 under 1 MPa pressure in the first direction must be smaller.

[0037] In one embodiment, the buffer 50 is a buffer frame comprising a plurality of strips.

[0038] Based on the above structure, the buffer frame with multiple strips can reduce material usage, lower production costs, and reduce weight. Furthermore, the strip layout effectively disperses concentrated stress generated by battery expansion, preventing excessive localized stress.

[0039] refer to Figure 2 The buffer frame includes a bottom strip 51 and two side strips 52. The bottom strip 51 extends along a second direction, and the two side strips 52 extend along a height direction. The two side strips 52 are spaced apart in the second direction, and the bottom ends of the two side strips 52 are respectively connected to or in contact with the two ends of the bottom strip 51 in the second direction. The first direction, the second direction, and the height direction are perpendicular to each other. In some embodiments, the bottom strip 51 and the two side strips 52 may be independent components. In other embodiments, the bottom strip 51 and the two side strips 52 may be integrally formed. For ease of description, in the accompanying drawings of this disclosure, Y is used to indicate the second direction, and Z is used to indicate the height direction.

[0040] During the assembly of the battery pack 100, adhesive is typically applied to the bottom of the casing 20 to bond and fix the battery 10. If there is a gap between the bottom ends of the two side strips 52 and the two ends of the bottom strip 51 in the second direction, the adhesive will overflow through the gap into the intermediate area formed by the two side strips 52 and the bottom strip 51, thus directly contacting the battery surface. After the adhesive cures, it forms a rigid structure, which cannot provide expansion space for the battery. When the battery expands during charging and discharging, the battery will directly contact this rigid structure, generating mechanical stress. This causes localized stress concentration on the battery surface, resulting in deformation of the battery casing or damage to the internal structure of the battery, thereby affecting the battery pack's lifespan and safety performance. Therefore, connecting or contacting the bottom ends of the two side strips 52 with the two ends of the bottom strip 51 in the second direction can prevent the adhesive from affecting the performance of the battery pack after curing. In addition, the intermediate area formed by the two side strips 52 and the bottom strip 51 can also provide expansion space for the battery.

[0041] refer to Figure 2 The buffer frame ends at the top of the two side strips 52 to form a top-open structure.

[0042] Based on the above structure, the open-top design allows for expansion space at the top of the battery, effectively preventing compressive mechanical stress caused by the battery being squeezed against the top structure during expansion. Furthermore, the open-top design also enhances the heat dissipation capacity of the battery top.

[0043] Continue to refer to Figure 2The dimension of battery 10 in the height direction is H1, in mm. The dimension of side strip 52 in the height direction is H2, in mm. 1 ≤ H1 / H2 ≤ 3.75, 80mm ≤ H1 ≤ 300mm, 80mm ≤ H2 ≤ 300mm. Preferably, 1.4 ≤ H1 / H2 ≤ 2.5, 100mm ≤ H1 ≤ 250mm, 100mm ≤ H2 ≤ 250mm. More preferably, 1.7 ≤ H1 / H2 ≤ 1.6, 120mm ≤ H1 ≤ 200mm, 120mm ≤ H2 ≤ 200mm. Alternatively, the ratio H1 / H2 can also be 2, 2.3, 2.6, 2.9, or 3.5.

[0044] If the ratio H1 / H2 is too large, meaning the dimension H2 of the side strip 52 in the height direction is relatively small, the side strip 52 cannot provide sufficient expansion space for the battery 10 during cyclic expansion, resulting in the expansion force of the battery 10 not being effectively absorbed. Furthermore, when the battery 10 expands, the expansion force may directly act on adjacent components, generating localized stress on the surface of the battery 10, causing deformation of the battery casing or even damage to the internal structure of the battery. If the ratio H1 / H2 is too small, meaning the dimension H2 of the side strip 52 in the height direction is relatively large, this leads to material waste and increased production costs. Within a reasonable range of 1 ≤ H1 / H2 ≤ 3.75, the side strip 52 can better provide expansion space for the battery, reduce material waste, and lower production costs.

[0045] In another embodiment, reference Figure 3 The buffer frame also includes a top strip 53. The top strip 53 extends in a second direction and is located on the top side of the two side strips 52. In some examples, the top strip 53, the two side strips 52, and the bottom strip 51 can be separate components. In other examples, the top strip 53, the two side strips 52, and the bottom strip 51 can also be integrally formed.

[0046] According to the above structure, the top strip 53 can provide support for the top of the battery, effectively absorbing the expansion force of the top of the battery, playing a buffering role, and protecting the battery from damage. In addition, the intermediate area formed by the top strip 53, the two side strips 52, and the bottom strip 51 can also provide expansion space for the battery.

[0047] refer to Figure 3 The top ends of the two side strips 52 are respectively connected to or in contact with the two ends of the top strip 53 in the second direction.

[0048] According to the above structure, the top strip 53, the two side strips 52, and the bottom strip 51 can form a continuous and closed buffer frame, providing a stable support structure for the battery 10. When the buffer frame is subjected to the battery expansion force, the expansion force can be effectively dispersed, avoiding stress concentration. In addition, this closed buffer frame can also prevent impurities such as dust, metal debris, or electrolyte leakage from entering the expansion space of the battery 10, improving the safety and reliability of the battery pack.

[0049] In another embodiment, reference Figure 4 In the height direction, the top ends of the two side strips 52 are arranged at intervals with the top strip 53.

[0050] Based on the above structure, a stable support structure can be provided for the battery 10, which can effectively disperse the expansion force of the battery when it expands and squeezes the buffer. In addition, the gap between the top of the two side strips 52 and the top strip 53 enhances air circulation, which is conducive to heat dissipation and avoids local heat accumulation.

[0051] refer to Figure 4 The dimension of battery 10 in the height direction is H1, in mm. The dimension of side strip 52 in the height direction is H2, in mm. 1.07≤H1 / H2≤4.3, 80mm≤H1≤300mm, 70mm≤H2≤290mm. Preferably, 1.5≤H1 / H2≤3.1, 100mm≤H1≤250mm, 80mm≤H2≤240mm. More preferably, 1.8≤H1 / H2≤1.8, 120mm≤H1≤200mm, 110mm≤H2≤180mm. Alternatively, the ratio H1 / H2 can also be 1.2, 2.1, 2.5, 3.5, 3.4, or 4.

[0052] If the ratio H1 / H2 is too large, meaning the dimension H2 of the side strip 52 in the height direction is relatively small, the side strip 52 cannot provide sufficient expansion space for the battery 10 during cyclic expansion, resulting in the battery's expansion force not being effectively absorbed. Furthermore, during battery expansion, the expansion force may directly act on adjacent components, generating localized stress on the surface of the battery 10, causing deformation of the battery casing or even damage to the internal structure. If the ratio H1 / H2 is too small, meaning the dimension H2 of the side strip 52 in the height direction is relatively large, this leads to material waste and increased production costs. Within a reasonable range of 1.07 ≤ H1 / H2 ≤ 4.3, the side strip 52 can better provide expansion space for the battery, reduce material waste, and lower production costs.

[0053] In another embodiment, reference Figure 5The buffer frame includes two strip-shaped portions 54 extending along the height direction and spaced apart from each other in a second direction. In the second direction, the distance from each strip-shaped portion 54 to the center of symmetry of the battery is D1, in mm. The battery dimension is H3, in mm. 0.3 ≤ D1 / H3 ≤ 0.49, 60 mm ≤ D1 ≤ 290 mm, 148 mm ≤ H3 ≤ 600 mm. Preferably, 0.36 ≤ D1 / H3 ≤ 0.44, 90 mm ≤ D1 ≤ 190 mm, 200 mm ≤ H3 ≤ 550 mm. More preferably, 0.39 ≤ D1 / H3 ≤ 0.42, 110 mm ≤ D1 ≤ 140 mm, 320 mm ≤ H3 ≤ 430 mm. Alternatively, the ratio D1 / H3 can also be 0.32, 0.34, 0.38, 0.4, or 0.46. For ease of description, in the accompanying drawings of this disclosure, E1 is used to indicate the center of symmetry of the battery in the second direction.

[0054] If the ratio D1 / H3 is too large, meaning the distance D1 from each strip 54 to the battery's center of symmetry is too large in the second direction (i.e., each strip 54 is too close to the edge of the battery 10), this increases the difficulty of the manufacturing process and reduces production efficiency. Furthermore, it prevents the battery from effectively buffering the central region during expansion. If the ratio D1 / H3 is too small, meaning the distance D1 from each strip 54 to the battery's center of symmetry is too small in the second direction (i.e., each strip 54 is too close to the center of symmetry), this also prevents the battery from effectively buffering the edges during expansion. Within a reasonable range of 0.3 ≤ D1 / H3 ≤ 0.49, the manufacturing process difficulty can be reduced, and production efficiency improved. Additionally, it ensures that the battery surface experiences uniform stress during expansion, avoiding excessive localized stress and ensuring battery safety and stability.

[0055] In another embodiment, reference Figure 6 The buffer frame includes two strip-shaped portions 55 extending along a second direction and spaced apart from each other in the height direction. In the height direction, the distance from each strip-shaped portion 55 to the center of symmetry of the battery is D2, in mm. The battery dimension is H1, in mm. 0.43≤D2 / H1≤0.483, 35mm≤D2≤140mm, 80mm≤H1≤300mm. Preferably, 0.44≤D2 / H1≤0.473, 60mm≤D2≤120mm, 100mm≤H1≤250mm. More preferably, 0.45≤D2 / H1≤0.463, 80mm≤D2≤100mm, 120mm≤H1≤200mm. Alternatively, the ratio D2 / H1 can also be 0.435, 0.445, 0.455, 0.46, or 0.47. For ease of description, in the accompanying drawings of this disclosure, E2 is used to indicate the center of symmetry of the battery in the height direction.

[0056] If the ratio D2 / H1 is too large, meaning the distance D2 from each strip 55 to the battery's center of symmetry E2 is too large in the height direction (i.e., each strip 55 is too close to the battery edge), this increases the difficulty of the manufacturing process and reduces production efficiency. Furthermore, it prevents the battery from effectively buffering the central region during expansion. If the ratio D2 / H1 is too small, meaning the distance D2 from each strip 55 to the battery's center of symmetry E2 is too small in the height direction (i.e., each strip 55 is too close to the battery's center of symmetry), this also prevents the battery from effectively buffering the edges during expansion. Within a reasonable range of 0.43 ≤ D2 / H1 ≤ 0.483, the manufacturing process difficulty can be reduced, and production efficiency improved. Additionally, it ensures that the battery surface experiences uniform stress during expansion, avoiding excessive localized stress and ensuring battery safety and stability.

[0057] refer to Figure 7 The buffer frame includes a bottom strip-shaped portion 51. In the height direction, the distance from the bottom strip-shaped portion 51 to the bottom end of the battery is H4, in mm, where 0.5mm ≤ H4 ≤ 20mm. Preferably, 6mm ≤ H4 ≤ 16mm. More preferably, 10mm ≤ H4 ≤ 12mm. Alternatively, the distance H4 from the bottom strip-shaped portion 51 to the bottom end of the battery 10 in the height direction can also be 2mm, 4mm, 8mm, 14mm, or 18mm.

[0058] If the distance H4 from the bottom strip 51 to the bottom of the battery is too small, meaning the bottom strip 51 is closer to the bottom of the battery, the contact area between the adhesive and the bottom surface of the battery is small, resulting in a smaller bonding surface. This will lead to a weak bond between the battery 10 and the bottom of the housing 20 when the battery 10 is assembled into the housing 20. Conversely, if the distance H4 from the bottom strip 51 to the bottom of the battery is too large (greater than 20mm), the contact area between the adhesive and the bottom surface of the battery 10 will be larger when the battery 10 is assembled into the housing. This will cause stress concentration in the area formed after the adhesive cures during the cyclic expansion of the battery 10, reducing the performance of the battery 10. Within the reasonable range of 0.5mm ≤ H4 ≤ 20mm, the battery 10 can be firmly bonded to the bottom of the housing 20 while ensuring that the performance of the battery 10 is not affected.

[0059] refer to Figure 3 The width of each strip is W, in mm, where 3 mm ≤ W ≤ 30 mm. Preferably, 8 mm ≤ W ≤ 25 mm. More preferably, 15 mm ≤ W ≤ 20 mm. Alternatively, the width W of each strip can also be 6 mm, 10 mm, 12 mm, 18 mm, 23 mm, or 28 mm.

[0060] If the width W of each strip is too large (greater than 30mm), it will result in material waste, increased production costs, and a larger space occupation for the strips. If the width W of each strip is too small (less than 3mm), it will not provide sufficient cushioning force and will easily be completely compressed and fail to provide cushioning when the battery expands. Within the reasonable range of 3 mm ≤ W ≤ 30mm, each strip can provide sufficient cushioning force, achieving a good cushioning effect. At the same time, it can reduce material waste and lower production costs.

[0061] refer to Figure 7 On the projection plane perpendicular to the first direction, the orthographic projection area of ​​the heat insulation pad 40 is S1, in mm. 2 The projected area of ​​the buffer frame is S2, in mm. 2 3% ≤ S2 / S1 ≤ 40%. Preferably, 10% ≤ S2 / S1 ≤ 35%. More preferably, 15% ≤ S2 / S1 ≤ 25%. Alternatively, the ratio S2 / S1 can also be 6%, 13%, 18%, 21%, 27%, 30%, or 37%.

[0062] If the ratio S2 / S1 is too small, meaning the projected area S2 of the buffer frame is too small, the buffer frame cannot provide sufficient buffering force, resulting in ineffective dispersion of battery expansion force, causing localized stress concentration, and reducing support stability. If the ratio S2 / S1 is too large, meaning the projected area S2 of the buffer frame is too large, it will lead to material waste and increase production costs. Within the range of 3% ≤ S2 / S1 ≤ 40%, the buffer frame can ensure that the battery expansion force can be effectively dispersed, avoiding localized stress concentration, reducing material waste, and lowering production costs.

[0063] In another embodiment, reference Figure 8 , the buffer 50 is the buffer pad 56.

[0064] According to the above structure, the buffer pad 56, through its continuous integral structure, can provide uniform support for the battery surface in contact with the buffer pad 56, which helps to more effectively disperse the expansion force generated by the battery during charging and discharging, and avoid excessive local stress.

[0065] Continue to refer to Figure 8 On the projection plane perpendicular to the first direction, the orthographic projection area of ​​the heat insulation pad 40 is S1, in mm. 2 The projected area of ​​the cushioning pad 56 is S3, in mm. 2The ratio S3 / S1 is 60% ≤ S3 / S1 ≤ 100%. Preferably, it is 70% ≤ S3 / S1 ≤ 90%. More preferably, it is 75% ≤ S3 / S1 ≤ 85%. Alternatively, the ratio S3 / S1 can also be 63%, 66%, 72%, 77%, 80%, 87%, 93%, or 97%.

[0066] If the ratio S3 / S1 is too small, meaning the projected area S3 of the buffer pad 56 is too small, the buffer pad 56 cannot provide sufficient buffering force, resulting in ineffective dispersion of battery expansion force, causing localized stress concentration, and reducing support stability. If the ratio S3 / S1 is too large, meaning the projected area S3 of the buffer pad 56 is too large, it will lead to material waste and increase production costs. Within the range of 60% ≤ S3 / S1 ≤ 100%, the buffer pad 56 can ensure that the battery expansion force can be effectively dispersed, avoiding localized stress concentration, reducing material waste, and lowering production costs.

[0067] refer to Figure 1 The battery pack consists of two batteries, including a first battery facing the heat insulation pad 40 and separated from the buffer member 50. The distance from the side of the first battery facing the buffer member 50 to the heat insulation pad 40 is D3, in mm. During the assembly of the battery pack 100, a certain preload is usually applied to ensure that components such as the battery 10, heat insulation pad 40, and buffer member 50 are fixed in place. This effectively prevents minor relative displacement or friction of components within the battery pack 100 due to vibration or other reasons, which could cause the components inside the battery pack to loosen or be damaged. Therefore, the distance D3 from the larger surface of the first battery facing the buffer member 50 to the heat insulation pad is also the gap D3 between the first battery and the heat insulation pad after the buffer member is compressed by the preload. D3 satisfies: 0.1mm ≤ D3 ≤ 5mm. Preferably, 1mm ≤ D3 ≤ 4mm. More preferably, 2mm ≤ D3 ≤ 3mm. Alternatively, the distance D3 between the large surface of the first battery facing the buffer and the heat insulation pad can also be 0.4mm, 0.7mm, 1.3mm, 1.6mm, 1.8mm, 2.3mm, 2.6mm, 2.8mm, 3.4mm, 3.8mm, 4.4mm or 4.8mm.

[0068] If the distance D3 from the large surface of the first battery facing the buffer 50 to the heat insulation pad 40 is too small, the buffer 50 cannot provide sufficient expansion space for the battery 10. During battery expansion, the buffer 50 may be completely compressed, causing the expansion force to act on adjacent components, resulting in excessive local stress on the battery surface and affecting the performance of the battery pack 100. Conversely, if the distance D3 from the large surface of the first battery facing the buffer 50 to the heat insulation pad 40 is too large within the limited space of the housing 20, the buffer 50 will excessively occupy the internal space of the housing 20, reducing the space utilization rate. Within a reasonable range of 0.1mm ≤ D3 ≤ 5mm, unnecessary space waste can be avoided, while providing sufficient expansion space for the battery to ensure the performance and safety of the battery pack.

[0069] In another embodiment, reference Figure 9 The battery pack may include two buffers 50. The two buffers 50 are respectively disposed on opposite sides of the heat insulation pad 40 in the first direction.

[0070] By providing buffer elements 50 on both sides of the heat insulation pad 40, expansion space can be further provided for the battery 10, and the expansion force of the batteries 10 on both sides can be absorbed simultaneously, preventing the heat insulation pad 40 from deforming due to pressure on one side, and effectively ensuring the heat insulation performance of the heat insulation pad 40. In addition, when thermal runaway occurs on one side of the battery 10, the double-sided buffer structure can provide bidirectional support for the heat insulation pad 40 and delay heat transfer.

[0071] <Example Electrical Equipment> This disclosure also provides an electrical device 200, which may include the battery pack 100 described above.

[0072] By way of example only, electrical equipment can be, but is not limited to, vehicles, ships, aircraft, household appliances, and industrial equipment. For example, vehicles can be passenger cars, trucks, construction vehicles, etc.

[0073] In addition, the electrical equipment 200 can also be used for the storage, conversion and release of recyclable electrical energy.

[0074] In a non-restrictive example, refer to Figure 10 The electrical equipment 200 can be an electric vehicle 200, and the battery pack 100 can be used as a power source to power the electric vehicle.

[0075] It should be noted that the elements described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0076] It should be understood that multiple components and / or parts can be provided by a single integrated component or part. Alternatively, a single integrated component or part can be divided into multiple separate components and / or parts. The use of the public designation "a" or "an" to describe a component or part does not imply the exclusion of other components or parts.

[0077] It should be understood that although terms such as “first” or “second” may be used in this disclosure to describe various elements (such as a first direction and a second direction), these elements are not defined by these terms, which are only used to distinguish one element from another.

[0078] The basic principles of this disclosure have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.

[0079] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A battery pack, characterized in that, include: Multiple batteries are arranged along a first direction; The housing contains a battery compartment for storing the multiple batteries. A heat insulation pad is disposed between two adjacent batteries in the first direction; and A buffer element is disposed on one side of the heat insulation pad in the first direction, wherein, 1%≤C1%≤20%, 5%≤C2%≤90%, C1%<C2%, and 0.02W / (m·K)≤R≤0.2W / (m·K), where C1% is the compressibility of the heat insulation pad when subjected to a pressure of 1 MPa in the first direction, C2% is the compressibility of the buffer when subjected to a pressure of 1 MPa in the first direction, and R is the thermal conductivity of the heat insulation pad, in W / (m·K).

2. The battery pack according to claim 1, characterized in that, The buffer is a buffer frame comprising multiple strip-shaped sections.

3. The battery pack according to claim 2, characterized in that, The buffer frame includes a bottom strip and two side strips. The bottom strip extends along a second direction, and the two side strips extend along a height direction. The two side strips are spaced apart in the second direction, and the bottom ends of the two side strips are connected to or in contact with the two ends of the bottom strip in the second direction, respectively. The first direction, the second direction, and the height direction are perpendicular to each other.

4. The battery pack according to claim 3, characterized in that, The buffer frame terminates at the top of the two side strips to form a top-open structure.

5. The battery pack according to claim 4, characterized in that, The dimension of the battery in the height direction is H1, in mm, and the dimension of the side strip in the height direction is H2, in mm. 1≤H1 / H2≤3.75, 80mm≤H1≤300mm, 80mm≤H2≤300mm.

6. The battery pack according to claim 3, characterized in that, The buffer frame also includes a top strip that extends along the second direction and is located on the top side of the two side strips.

7. The battery pack according to claim 6, characterized in that, The top ends of the two side strips are respectively connected to or in contact with the two ends of the top strip in the second direction.

8. The battery pack according to claim 6, characterized in that, In the height direction, the top ends of the two side strips are spaced apart from the top strip.

9. The battery pack according to claim 8, characterized in that, The dimension of the battery in the height direction is H1, in mm, and the dimension of the side strip in the height direction is H2, in mm. 1.07≤H1 / H2≤4.3, 80mm≤H1≤300mm, 70mm≤H2≤290mm.

10. The battery pack according to claim 2, characterized in that, The buffer frame includes two strip-shaped portions extending along the height direction and spaced apart from each other in a second direction; in the second direction, the distance from each strip-shaped portion to the center of symmetry of the battery is D1 in mm, the size of the battery is H3 in mm, 0.3≤D1 / H3≤0.49, 60mm≤D1≤290mm, 148mm≤H3≤600mm, wherein the first direction, the second direction and the height direction are perpendicular to each other.

11. The battery pack according to claim 2, characterized in that, The buffer frame includes two strip-shaped portions extending along a second direction and spaced apart from each other in the height direction; in the height direction, the distance from each strip-shaped portion to the center of symmetry of the battery is D2 in mm, the size of the battery is H1 in mm, 0.43≤D2 / H1≤0.483, 35mm≤D2≤140mm, 80mm≤H1≤300mm, wherein the first direction, the second direction and the height direction are perpendicular to each other.

12. The battery pack according to claim 2, characterized in that, The buffer frame includes a bottom strip-shaped portion; in the height direction, the distance from the bottom strip-shaped portion to the bottom end of the battery is H4, in mm, where 0.5mm≤H4≤20mm.

13. The battery pack according to claim 2, characterized in that, The width of each strip is W, in mm, where 3 mm ≤ W ≤ 30 mm.

14. The battery pack according to claim 2, characterized in that, On a projection plane perpendicular to the first direction, the orthographic projection area of ​​the heat insulation pad is S1, in mm. 2 The projected area of ​​the buffer frame is S2, in mm. 2 3%≤S2 / S1≤40%.

15. The battery pack according to claim 1, characterized in that, The buffer is a cushioning pad.

16. The battery pack according to claim 15, characterized in that, On a projection plane perpendicular to the first direction, the orthographic projection area of ​​the heat insulation pad is S1, in mm. 2 The projected area of ​​the buffer pad is S3, in mm. 2 60%≤S3 / S1≤100%.

17. The battery pack according to claim 1, characterized in that, The two batteries include a first battery that is opposite to the heat insulation pad and separated from the buffer member. The distance from the side of the first battery facing the buffer member to the heat insulation pad is D3, in mm, where 0.1 mm ≤ D3 ≤ 5 mm.

18. The battery pack according to claim 1, characterized in that, The two buffer elements are respectively disposed on opposite sides of the heat insulation pad in the first direction.

19. The battery pack according to claim 1, characterized in that, The heat insulation pad is a nanoplate, and / or the cushioning element is made of solid silicone rubber or MPP.

20. The battery pack according to claim 1, characterized in that, The large surfaces of the two batteries face each other, with 1% ≤ C1% ≤ 17% and 5% ≤ C2% ≤ 88%.

21. An electrical appliance, characterized in that, Includes the battery pack according to any one of claims 1 to 19.

Images