Patent Description:
Battery packs applied to, for example, electric vehicles in the related art mainly include a housing and a plurality of battery modules mounted in the housing. Each of the battery modules is formed by a plurality of cells assembled together.

Users' requirements on the battery life of electric vehicles are becoming higher. However, in the case of limited space at the bottom of the vehicle body, power battery packs in the prior art have the problem of low space utilization and the energy density of such power battery packs cannot meet the requirements, which gradually becomes an important factor hindering the development of electric vehicles.

Examples of such previously known power battery packs are derivable from <CIT>, <CIT>, <CIT>, as well as <CIT>.

In the related art, as shown in <FIG>, a housing <NUM>" of a battery pack <NUM>' is often divided into a plurality of mounting regions for battery modules <NUM>' by width-direction transverse beams <NUM>' and length-direction transverse beams <NUM>'. For example, the battery modules <NUM>' in the battery pack disclosed in <CIT> are fixed on the width-direction transverse beams <NUM>' or the length-direction transverse beams <NUM>' by screws or other means. The battery module <NUM>' includes a plurality of cells arranged in sequence. A plurality of cells are arranged to form a cell array. End beams and/or side beams are disposed outside the cell array. Usually, both end beams and side beams are disposed. The end beams and the side beams are fixed to define a space for accommodating the cell array. In addition, the end beams and the side beams are connected by screws, or by other connecting members such as a pull rod, so as to fix the cell array.

The applicant finds through experiments and analysis that because the battery modules <NUM>' are fixed on the width-direction transverse beams <NUM>' or the length-direction transverse beams <NUM>' by screws, space is wasted, and the use of screws or other connecting members increases the weight, reducing the energy density. In addition, because the battery modules <NUM>' are designed with the end beams and side beams which all have a certain thickness and height, space inside the housing <NUM>" is wasted, leading to low utilization of the volume of the housing <NUM>". Generally, for the battery pack <NUM>' in the prior art, the ratio of the sum of the volumes of cells in the housing <NUM>" to the volume of the housing <NUM>" is about <NUM>%, or even lower than <NUM>%.

For the battery pack <NUM>' provided in the prior art, the end beams and the side beams of the battery module <NUM>' and the connection and mounting manners inside the battery pack <NUM>' reduce the utilization of the space inside the housing <NUM>". As a result, in the battery pack <NUM>', the ratio of the sum of the volumes of cells to the volume of the housing <NUM>" is too low, and the energy density cannot meet the increasing requirements of users on the battery life of electric vehicles, which gradually becomes an important factor hindering the development of electric vehicles. In addition, a complicated assembly process is required, and complex assembly procedures need to be performed. To be specific, first, cells need to be assembled to form a battery module, and then the battery module needs to be mounted in the housing, leading to increased labor and material costs. In addition, multiple assembly procedures required in the assembly process of the battery pack lead to an increase in defect rate and an increase in the possibility of loosening and unstable mounting of the battery pack, adversely affecting the quality of the battery pack and reducing the stability and reliability of the battery pack.

This application is intended to resolve at least one of the technical problems existing in the prior art. In view of this, an object of the present application is to provide a battery pack, which has the advantages of high space utilization, high energy density, long battery life, high reliability, low cost, and high quality.

The objects above are solved by means of battery pack according to independent claim <NUM>, an electric vehicle according to independent claim <NUM>, and/or an energy storage device according to independent claim <NUM>. Distinct embodiments are derivable from the dependent claims.

According to an embodiment in a first aspect of the present invention, a battery pack is provided. The battery pack includes a housing; and a plurality of cells, provided in the housing, where the sum V1 of the volumes of the plurality of cells and the volume V2 of the battery pack satisfy V1/V2≥<NUM>%. The battery pack has a first direction and a second direction perpendicular to each other. A length direction of the cell is arranged along the first direction of the battery pack, and the plurality of cells are arranged along the second direction of the battery pack. The housing accommodates only one cell along the first direction. The cell includes a cell body, and the length of the cell body is <NUM>-<NUM>.

In the power battery according to the embodiment of the present application, by limiting the ratio of the sum of the volumes of the cells to the volume of the battery pack, that is, V1/V2, to be ≥<NUM>%, the space utilization of the battery pack is improved, and more cells can be arranged in the battery pack. That is, more energy supply structures are arranged in the unit space to increase the energy density, thereby increasing the battery life without expanding the occupied space. Moreover, in the process of assembling the battery pack, the cost is reduced, and the quality and reliability of the battery pack are improved.

According to an embodiment in a second aspect of the present application, an electric vehicle is provided, which includes the battery pack according to the embodiment in the first aspect of the present application.

In the electric vehicle according to the embodiment of the present application, the battery life can be improved without expanding the space occupied by the battery by using the battery pack according to the embodiment in the first aspect of the present application.

According to an embodiment in a third aspect of the present application, an energy storage device is provided, which includes the battery pack according to the embodiment in the first aspect of the present application.

Other aspects and advantages of this application will be given in the following description, some of which will become apparent from the following description or may be learned from practices of this application.

Related art:
<NUM>' battery pack, <NUM>" housing, <NUM>' battery module, <NUM>' length-direction transverse beam, <NUM>' width-direction transverse beam.

A length direction of battery pack <NUM>, B width direction of battery pack <NUM>, C height direction of battery pack <NUM>.

L length of cell body <NUM>, Hwidth of cell body <NUM>, D thickness of cell body <NUM>, W width of vehicle body, F width of housing <NUM>.

Embodiments of this application are described in detail below, and examples of the embodiments are shown in accompanying drawings, where the same or similar elements or the elements having same or similar functions are denoted by the same or similar reference numerals throughout the description. The embodiments described below with reference to the accompanying drawings are exemplary and used only for explaining this application, and should not be construed as a limitation on this application.

In the description of this application, it should be understood that orientation or position relationships indicated by the terms such as "vertical", "transverse", "length", "width", "thickness", "inside", and "outside" are based on orientation or position relationships shown in the accompanying drawings, and are used only for ease and brevity of illustration and description, rather than indicating or implying that the mentioned apparatus or component must have a particular orientation or must be constructed and operated in a particular orientation. Therefore, such terms should not be construed as limiting of this application.

In addition, in the description of this application, "a plurality of" means two or more than two.

Considering the status of battery packs in the related art, this application provides a battery pack and an electric vehicle having the battery pack. The battery pack has the advantages of high space utilization, high energy density, and long battery life.

A battery pack <NUM> according to an embodiment of this application is described with reference to accompanying drawings.

As shown in <FIG>, the battery pack <NUM> according to an embodiment of the present application includes a housing <NUM> and a plurality of cells <NUM>.

The plurality of cells <NUM> are provided in the housing <NUM>, and the housing <NUM> can be understood as a housing for accommodating the plurality of cells <NUM>. For example, it may include a tray <NUM> and an upper cover <NUM>. The tray <NUM> and the upper cover <NUM> work together to define a space accommodating the plurality of cells <NUM>. The plurality of cells <NUM> are provided in the tray <NUM>, and are covered by the upper cover <NUM>. The sum V1 of the volumes of the plurality of cells <NUM> and the volume V2 of the battery pack <NUM> satisfy V1/V2≥<NUM>%.

Those skilled in the art can understand that V1 is the product of the volume of each cell <NUM> and the number of cells <NUM>, that is, V1 is the total volume of the plurality of cells <NUM>; and V2 is the overall volume of a three-dimensional shape defined by an external profile of the battery pack <NUM>.

In the battery pack <NUM> according to the embodiment of the present application, by limiting the ratio of the sum V1 of the volumes of the cells <NUM> to the volume V2 of the battery pack <NUM>, that is, V1/V2, to be ≥<NUM>%, the space utilization of the battery pack <NUM> is improved, and more cells <NUM> can be arranged in the battery pack <NUM>. That is, more energy supply structures are arranged in the unit space to increase the energy density, thereby increasing the battery life without expanding the occupied space. Moreover, in the process of assembling the battery pack, the cost is reduced, and the quality and reliability of the battery pack are improved. In the battery pack provided in this application, the housing accommodates only one cell along a first direction. The cell includes a cell body, and the length of the cell body is <NUM>-<NUM> and is arranged along the first direction in the battery pack. The plurality of cells are arranged along the second direction. The long cells are arranged and located in the battery pack, to form a battery pack having a volume utilization of <NUM>% or higher. In this way, the space utilization, the energy density and the battery life of an electric vehicle using the battery pack are improved.

In some specific embodiments of this application, the ratio of the sum V1 of the volumes of the cells <NUM> to the volume V2 of the battery pack <NUM> satisfy V1/V2≥<NUM>%.

In some other specific embodiments of this application, the ratio of the sum V1 of the volumes of the cells <NUM> to the volume V2 of the battery pack <NUM> satisfy V1/V2≥<NUM>%.

It can be understood that V2 is the overall volume of a three-dimensional shape defined by an external profile of the battery pack <NUM>, that is, a volume including the internal space of the battery pack <NUM>, a volume of the three-dimensional area enclosed in space by the external profile of the battery pack <NUM>. In electric vehicles, V1/V2 can be understood as space utilization.

Those skilled in the art can understand that due to some factors, for example, peripheral components will occupy the internal space of the housing <NUM>, including an anti-collision space at a bottom of the tray, a liquid cooling system, a thermal insulation material, an insulation protection, an accessory for thermal safety, a flame exhaust passage, and a high-voltage power distribution module, etc., so the peak value of V1/V2 is usually <NUM>%, that is, V1/V2≤<NUM>%.

The battery pack <NUM> according to a specific embodiment of the present application is described below with reference to the drawings, in which a length direction of the battery pack <NUM> is indicated by an arrow A, a width direction of the battery pack <NUM> is indicated by an arrow B, and a height direction of the battery pack <NUM> is indicated by an arrow C.

In some specific embodiments of the present application, as shown in <FIG>, a length direction of the cell <NUM> is arranged along the width direction B of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM>, thus promoting V1/V2 of the battery pack <NUM> to increase to <NUM>%, <NUM>%, <NUM>%, <NUM>% or higher. Moreover, to reserve enough space for mounting other electronic components (such as battery management system, BMS), generally the space utilization of the battery pack <NUM> is set below <NUM>%.

In some specific embodiments of the present application, as shown in <FIG> and <FIG>, in the width direction B of the battery pack <NUM>, a distance from the cell <NUM> to sidewalls of the housing <NUM> is less than the length of the cell <NUM>. Specifically, in the width direction B of the battery pack <NUM>, a shortest distance from one end of the cell <NUM> to a side beam of the housing <NUM> adjacent to the end of the cell <NUM> is L1, a shortest distance from the other end of the cell <NUM> to a side beam of the housing <NUM> adjacent to the other end of the cell <NUM> is L2, and the length L of the cell <NUM> satisfies: L1 + L2 < L. In this way, the battery pack <NUM> cannot additionally accommodate another cell <NUM> in the width direction B.

In other words, the housing <NUM> accommodates only one cell <NUM> in the width direction B of the battery pack <NUM>. That is, in the width direction B of the battery pack <NUM>, the cell <NUM> cannot be arranged in a pattern including two or more cells. When at least two layers of cells <NUM> are provided in the battery pack <NUM> along the height direction C of the battery pack <NUM>, at least one layer of cells <NUM> can accommodate only one cell in the width direction B of the battery pack <NUM>. The description "accommodate only one cell <NUM>" means that in the width direction B of the battery pack <NUM>, only one cell <NUM> can be arranged side by side. However, in the height direction C of the battery pack <NUM>, although two layers of cells can be provided, it is not intended to arrange more than one cell <NUM> in the width direction B of the battery pack <NUM>.

It can be understood that in the width direction B of the battery pack <NUM>, side beams are provided at two sides of the housing <NUM>; and in the length direction A of the battery pack <NUM>, end beams are provided at two ends of the housing <NUM>.

In some specific embodiments of this application, as shown in <FIG> and <FIG>, the length of the cell <NUM> extends across the entire width direction B of the battery pack <NUM>. That is, along the width direction B of the battery pack <NUM>, the cell <NUM> extends from one side to the other side of the housing <NUM>, and the length of the cell <NUM> is filled in the width direction B of the battery pack <NUM>. The housing <NUM> cannot accommodate two or more cells <NUM> in the width direction B of the battery pack <NUM>. Two ends of the cell <NUM> in the length direction can be fitted to the two opposite side walls of the housing <NUM> in the width direction B, for example, fixed to the housing <NUM>. As a result, no width-direction transverse beams and length-direction transverse beams are required in the housing <NUM>, and the connected cells <NUM> can directly act as the intermediate beams. This greatly simplifies the structure of the housing <NUM>, and reduces the space occupied by the intermediate beams and by structures for mounting the cells <NUM>, thereby improving the space utilization and improving the battery life.

The embodiments of the present application are not limited to not providing width-direction transverse beams and length-direction transverse beams. In some embodiments of the present application, as shown in <FIG>, a width-direction transverse beam <NUM> can be provided in the housing <NUM>. The width-direction transverse beam <NUM> extends along the width direction B of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM> to form a battery array. The width-direction transverse beam <NUM> divides the battery array into at least two parts along the length direction A of the battery pack <NUM>. Each part of the battery array includes at least one cell <NUM>, and each part of the battery array constitutes a battery module <NUM>.

In some other embodiments of the present application, as shown in <FIG>, a length-direction transverse beam <NUM> can also be provided in the housing <NUM>. The length-direction transverse beam <NUM> extends along the length direction A of the battery pack <NUM>. The length direction of the cell <NUM> is arranged along the width direction B of the battery pack <NUM>. A plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM> to form a battery array. At least two rows of battery arrays are arranged in the housing <NUM> along the width direction B of the battery pack <NUM>. Each row of battery array includes a plurality of cells <NUM> arranged along the length direction A of the battery pack <NUM>. The length-direction transverse beam <NUM> is located between two adjacent rows of battery arrays.

In some specific embodiments of this application, the housing <NUM> includes side beams located at two sides of the battery pack <NUM> in the width direction B, and both ends in the length direction of the cell <NUM> are supported by the side beams. The housing <NUM> includes end beams located at two ends of the battery pack <NUM> in the length direction A, and the end beams provide an inward pressing force against the cell <NUM> adjacent to them.

As shown in <FIG> and <FIG>, the housing <NUM> has a first side beam <NUM>, a second side beam <NUM>, a first end beam <NUM> and a second end beam <NUM>. The first side beam <NUM>, the second side beam <NUM>, the first end beam <NUM> and second end beam <NUM> are sequentially connected end to end. The first side beam <NUM> and the second side beam <NUM> are opposite in the width direction B of the battery pack <NUM>, and the first end beam <NUM> and the second end beam <NUM> are opposite in the length direction A of the battery pack <NUM>. The first side beam <NUM> and the second side beam <NUM> provide support for the two ends of the cell <NUM> in the length direction, that is, one end of the cell <NUM> is supported by the first side beam <NUM> and the other end is supported by the second side beam <NUM>. The first end beam <NUM> and the second end beam <NUM> provide a pressing force against two sides of the cell <NUM> in the thickness direction. That is, the first end beam <NUM> applies a force toward the second end beam <NUM> to the cell <NUM> arranged adjacent to the first end beam <NUM>, and the second end beam <NUM> applies a force toward the first end beam <NUM> to the cell <NUM> arranged adjacent to the second end beam <NUM>, to allow a plurality of cells <NUM> to be tightly arranged between the first end beam <NUM> and the second end beam <NUM> along the length direction A of the battery pack <NUM>, where the plurality of cells <NUM> fit to each other. In addition, the first end beam <NUM> and the second end beam <NUM> can limit the plurality of cells <NUM> in the length direction A of the battery pack <NUM>. Particularly when the cell <NUM> expands slightly, they can buffer and provide an inward pressing force against the cell <NUM>, to prevent excessive expansion and deformation of the cell <NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the width direction B of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM> to form a battery array. There are at least two layers of battery arrays in the housing <NUM> along the height direction C of the battery pack <NUM>. As a result, the number of cells <NUM> is optimized, whereby the space utilization is increased to increase the energy density, and BIC and low-voltage sampling are easier to be integrally implemented.

In some specific embodiments of the present application, as shown in <FIG> and <FIG>, the length direction of the cell <NUM> is arranged along the length direction A of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM>. This leads to a space utilization of the battery pack <NUM> of <NUM>%, <NUM>%, <NUM>%, <NUM>% or higher.

In some specific embodiments of the present application, as shown in <FIG> and <FIG>, in the length direction A of the battery pack <NUM>, a distance from the cell <NUM> to end walls of and the housing <NUM> is less than the length of the cell <NUM>. Specifically, in the length direction A of the battery pack <NUM>, a shortest distance from one end of the cell <NUM> to an end beam of the housing <NUM> adjacent to the end of the cell <NUM> is L3, a shortest distance from the other end of the cell <NUM> to an end beam of the housing <NUM> adjacent to the other end of the cell <NUM> is L4, and the length L of the cell <NUM> satisfies: L3 + L4 < L. In this way, the battery pack <NUM> cannot additionally accommodate another cell <NUM> in the length direction A.

In other words, the housing <NUM> accommodates only one cell <NUM> in the length direction A of the battery pack <NUM>. That is, in the length direction A of the battery pack <NUM>, the cell <NUM> cannot be arranged in a pattern including two or more cells.

It can be understood that in the width direction B of the battery pack <NUM>, side beams are provided at two sides of the housing <NUM>; and in the length direction A of the battery pack <NUM>, end beams are provided at two sides of the housing <NUM>.

In some specific embodiments of this application, as shown in <FIG> and <FIG>, the length of the cell <NUM> extends across the entire length direction A of the battery pack <NUM>. That is, along the length direction A of the battery pack <NUM>, the cell <NUM> extends from one end to the other end of the housing <NUM>, and the length of the cell <NUM> is filled in the length direction A of the battery pack <NUM>. The housing <NUM> cannot accommodate two or more cells <NUM> in the length direction A of the battery pack <NUM>. Two ends of the cell <NUM> in the length direction can be engaged to the two opposite end walls of the housing <NUM> in the length direction A, for example, fixed to the housing <NUM>. As a result, no width-direction transverse beams and length-direction transverse beams are required in the housing <NUM>, and the connected cells <NUM> can directly act as the intermediate beams. This greatly simplifies the structure of the housing <NUM>, and reduces the space occupied by the intermediate beams and by structures for mounting the cells <NUM>, thereby improving the space utilization and improving the battery life.

The embodiments of the present application are not limited to not providing length-direction transverse beams and width-direction transverse beams. In some embodiments of the present application, as shown in <FIG>, a length-direction transverse beam <NUM> can be provided in the housing <NUM>. The length-direction transverse beam <NUM> extends along the length direction A of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM> to form a battery array. The length-direction transverse beam <NUM> divides the battery array into at least two parts along the width direction B of the battery pack <NUM>. Each part of the battery array includes at least one cell <NUM>, and each part of the battery array constitutes a battery module <NUM>.

In some other embodiments of the present application, a width-direction transverse beam <NUM> can also be provided in the housing <NUM>. The width-direction transverse beam <NUM> extends along the width direction B of the battery pack <NUM>. The length direction of the cell <NUM> is arranged along the length direction A of the battery pack <NUM>. A plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM> to form a battery array. At least two rows of battery arrays are arranged in the housing <NUM> along the length direction A of the battery pack <NUM>. Each row of battery array includes a plurality of cells <NUM> arranged along the width direction B of the battery pack <NUM>. The width-direction transverse beam <NUM> is located between two adjacent rows of battery arrays.

In some specific embodiments of this application, the housing <NUM> includes end beams located at two ends of the battery pack <NUM> in the length direction A, and both ends in the length direction of the cell <NUM> are supported by the end beams. The housing <NUM> includes side beams located at two sides of the battery pack <NUM> in the width direction B, and the side beams provide an inward pressing force against the cell <NUM> adjacent to them.

As shown in <FIG>, the housing <NUM> has a first side beam <NUM>, a second side beam <NUM>, a first end beam <NUM> and a second end beam <NUM>. The first side beam <NUM>, the second side beam <NUM>, the first end beam <NUM> and second end beam <NUM> are sequentially connected end to end. The first side beam <NUM> and the second side beam <NUM> are opposite in the width direction B of the battery pack <NUM>, and the first end beam <NUM> and the second end beam <NUM> are opposite in the length direction A of the battery pack <NUM>. The first end beam <NUM> and the second end beam <NUM> provide support for the two ends of the cell <NUM> in the length direction, that is, one end of the cell <NUM> is supported by the first end beam <NUM> and the other end is supported by the second end beam <NUM>. The first side beam <NUM> and the second side beam <NUM> provide a pressing force against two sides of the cell <NUM> in the thickness direction. That is, the first side beam <NUM> applies a force toward the second side beam <NUM> to the cell <NUM> arranged adjacent to the first side beam <NUM>, and the second side beam <NUM> applies a force toward the first side beam <NUM> to the cell <NUM> arranged adjacent to the second side beam <NUM>, to allow a plurality of cells <NUM> to be tightly arranged between the first side beam <NUM> and second side beam <NUM> along the width direction B of the battery pack <NUM>, where the plurality of cells <NUM> fit to each other. In addition, the first side beam <NUM> and the second side beam <NUM> can limit the plurality of cells <NUM> in the width direction B of the battery pack <NUM>. Particularly when the cell <NUM> expands slightly, they can buffer and provide an inward pressing force against the cell <NUM>, to prevent excessive expansion and deformation of the cell <NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the length direction A of the battery pack <NUM>, and a plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM> to form a battery array. There is at least one layer of battery arrays in the housing <NUM> along the height direction C of the battery pack <NUM>. As a result, the number of cells <NUM> is optimized, whereby the space utilization is increased to increase the energy density, and BIC and low-pressure sampling are easier to be integrally implemented.

In some specific embodiments of the present application, a plurality of cells <NUM> can be assembled into multiple battery modules <NUM>. The multiple battery modules <NUM> can be arranged along the length direction A of the battery pack <NUM> (as shown in <FIG>), the multiple battery modules <NUM> can also be arranged along the width direction B of the battery pack <NUM> (as shown in <FIG>), or the multiple battery modules <NUM> can also be arranged along the height direction C of the battery pack <NUM> to form a multilayer structure (as shown in <FIG>). In other words, regardless of the cells <NUM> extending along the width direction B or the length direction A of the battery pack <NUM>, the plurality of cells <NUM> can be arranged in multiple layers along the height direction C of the battery pack <NUM>. The multiple battery modules <NUM> can also be arranged along both the length direction A and the height direction C of the battery pack <NUM>, or along both the width direction A and the height direction C of the battery pack <NUM>. As a result, the number of battery modules <NUM> is optimized, whereby the space utilization is increased to increase the energy density, and BIC and low-voltage sampling are easier to be integrally implemented. It should be understood that the battery module <NUM> in the embodiment of the present application does not have structures such as end beams and side beams.

In the related art, due to the small size and short length of the cell, the two opposite ends of the cell cannot be fitted to the two opposite side walls of the housing <NUM>". Therefore, the length-direction transverse beams <NUM>' and/or the width-direction transverse beams <NUM>' (as shown in <FIG>) is/are needed to be provided in the housing <NUM>", to facilitate the cell assembly. When the cells are mounted in the housing <NUM>" by means of the battery modules <NUM>', there will be multiple cells along the width direction of the battery pack <NUM>'. That is, the cell does not extend between the two opposite side walls, but extend between two opposite length-direction transverse beams <NUM>' or width-direction transverse beams <NUM>'. The battery module is fixed to an adjacent length-direction transverse beam <NUM>' and/or width-direction transverse beams <NUM>' by a fastener.

Since the length-direction transverse beams <NUM>' and/or the width-direction transverse beams <NUM>' are provided in the housing <NUM>" in the related art, the length-direction transverse beams <NUM>' and/or the width-direction transverse beams <NUM>' occupy a large mounting space for accommodating the cells in the housing <NUM>", causing a low space utilization of the housing <NUM>". Generally, the ratio of the sum of the volumes of cells to the volume of the housing <NUM>" is about <NUM>%, or even lower. In other words, only about <NUM>% of the space in the housing <NUM>" in the related art is available for mounting the cells, resulting in a limited number of cells accommodated in the housing <NUM>", limited capacity and voltage of the entire battery pack <NUM>', and poor battery life of the battery pack <NUM>'.

The battery pack <NUM> according to the embodiments of the present application can, on the one hand, reduce the use of length-direction transverse beams and/or width-direction transverse beams in the housing <NUM>. Even the length-direction transverse beams and/or the width-direction transverse beams may be not provided in the housing <NUM>, to reduce the space occupied by the length-direction transverse beams and/or the width-direction transverse beams in the housing <NUM>, and improve the space utilization of the housing <NUM>. On the other hand, it can reduce the use of end beams and side beams in the battery module <NUM>, and reduce the space occupied by the end beams and the side beams in the housing <NUM>, to improve the space utilization of the housing <NUM>. As many cells <NUM> as possible are arranged in the housing <NUM>, to increase the capacity, voltage and battery life of the entire battery pack.

Moreover, since no length-direction transverse beams and/or width-direction transverse beams are needed to be arranged in the housing <NUM>, on the one hand, the manufacturing process of the housing <NUM> is simplified, the assembly complexity of cells <NUM> is reduced, and the production cost is reduced; and on the other hand, the weights of the housing <NUM> and the entire battery pack <NUM> are reduced, achieving a light weight of the battery pack <NUM>. In particular, when the battery pack <NUM> is mounted on an electric vehicle, the battery life of the electric vehicle is improved, and a light weight of the electric vehicle is achieved.

In addition, the cell <NUM> itself can be used to strengthen the structural strength of the housing <NUM>. That is, there is no need to provide a strengthening structure for enhancing the structural strength in the housing <NUM>, and the cell <NUM> itself can directly replace the strengthening structure to ensure the structural strength of the housing <NUM>, thus ensuring that the housing <NUM> is not prone to deformation under the action of an external force. Compared with the battery pack disclosed in Chinese Patent Document <CIT>, the housing <NUM> can not only accommodate and protect the cells <NUM>, but also support the cells <NUM> to improve the overall load-bearing capacity of the battery pack <NUM>. The length of the cell <NUM> enhances the strength of the battery pack <NUM>. In addition, the surface area of a single cell <NUM> is increased, to increase the heat dissipation area and increase the heat dissipation rate of the cell <NUM>, thereby improving the safety of the entire battery pack <NUM> and making the battery pack <NUM> safer and more reliable.

In some specific embodiments of this application, the cell <NUM> includes a cell body <NUM> (which can be understood as a body part excluding small-sized protruding structures such as electrode tabs), and the volume V of the cell body <NUM> and the energy E of the cell body <NUM> satisfy: V/E≤<NUM><NUM>. Therefore, it is possible to ensure a sufficient heat dissipation area to ensure the heat dissipation effect, and reduce the volume ratio of the cells <NUM>, which is beneficial to the compact arrangement of a plurality of cells <NUM> in the battery pack <NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the housing <NUM> is different from the battery pack housing disclosed in Chinese Patent Document <CIT>, especially in terms of the size and load bearing capacity. The housing <NUM> includes a vehicle tray <NUM> that is fitted and connected to a vehicle body, to form a structure fitted to the vehicle body for accommodating and carrying the cells <NUM>. The vehicle tray <NUM> is a separately produced tray for accommodating and mounting the cells <NUM>. After the cell <NUM> is mounted in the vehicle tray <NUM>, the vehicle tray <NUM> can be mounted to the vehicle body by a fastener. For example, the vehicle tray is hanged on a chassis of an electric vehicle, to accommodate and bear the cells.

When the battery pack <NUM> is used as a battery pack for providing electric energy on a vehicle, the length direction of the cell <NUM> can be arranged along a length direction of the vehicle body, that is, the front and rear directions of the vehicle. At this time, the length L of the cell body <NUM> of the cell <NUM> may be <NUM>-<NUM>. In some embodiments, L may be <NUM>-<NUM>, so that the length of the cell <NUM> can be adapted to the length of the vehicle. When the battery pack <NUM> is used as a battery pack for providing electric energy on a vehicle, the length direction of the cell <NUM> can be arranged along a width direction of the vehicle body, that is, the left and right directions of the vehicle. At this time, the length L of the cell body <NUM> of the cell <NUM> may be <NUM>-<NUM>, so that the length of the cell <NUM> can be adapted to the width of the vehicle. In some embodiments of the present application, the length L of the cell body is <NUM>-<NUM>. Further, the length L of the cell body may be <NUM>-<NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the housing <NUM> may also be directly formed on the electric vehicle, that is, the housing <NUM> is a device for mounting the cells <NUM> and formed at any appropriate position on the electric vehicle. For example, the housing <NUM> may be formed on the chassis of the electric vehicle.

In some specific embodiments of the present application, when the battery pack <NUM> is arranged on an electric vehicle, unlike the battery pack disclosed in Chinese Patent Document <CIT>, the battery pack <NUM> also includes at least one of a battery management system (BMS), a battery connector, a battery sampler, a battery thermal management system, and other components required for the vehicle battery. The width direction B of the battery pack <NUM> is arranged along the width direction of the vehicle body, that is, the left and right directions of the vehicle; and the length direction of the battery pack <NUM> is arranged along the length direction of the vehicle body, that is, the front and rear directions of the vehicle. The present application is not limited thereto. The width direction B of the battery pack <NUM> may be arranged along the length direction of the vehicle body, and the length direction A of the battery pack <NUM> may be arranged along the width direction of the vehicle body. In some embodiments of the present application, the first direction and the second direction are two directions perpendicular to each other with the battery pack as a reference. The first direction may be the width direction of the battery pack, and the second direction may be the length direction of the battery pack.

Those skilled in the art can understand that the orientation of the cells <NUM> in the battery pack <NUM> and the orientation of the battery pack <NUM> on the electric vehicle can be combined in various forms. For example, the length direction of the cell <NUM> can be arranged along the width direction B of the battery pack <NUM> or along the length direction A of the battery pack <NUM>. The width direction B of the battery pack <NUM> can be arranged along the width direction of the vehicle body or along the length direction of the vehicle body. For example, regardless of the width direction B of the battery pack <NUM> being arranged along the width direction of the vehicle body or along the length direction of the vehicle body, the length direction of the cell <NUM> is arranged along the width direction of the vehicle body. The relative direction of arrangement of the cell <NUM>, the battery pack <NUM> and the vehicle body can be arranged according to the practical application to meet various requirements.

The cell <NUM> according to an embodiment of the present application will be described below with reference to the accompanying drawings.

In the following specific embodiments, the length L, the width H and the thickness D are in millimeters (mm), the surface area S is in square millimeter (mm <NUM>), the volume V is in cubic millimeter (mm<NUM>), and the energy E is in watt-hour (Wh).

As shown in <FIG>, the cell <NUM> according to an embodiment of the present application includes a cell body <NUM>. It can be understood that the cell body <NUM> is a body part excluding small-sized protruding structures such as electrode tabs. The cell body <NUM> has a length L, a width H, and a thickness D.

The length L of the cell body <NUM> is greater than the width H of the cell body <NUM>, the width H of the cell body <NUM> is greater than the thickness D of the cell body <NUM>, and the length L of the cell body <NUM> and the width H of the cell body <NUM> satisfy: L/H=<NUM>-<NUM>. In some specific embodiments of the present application, the length L of the cell body <NUM> and the width H of the cell body <NUM> satisfy: L/H=<NUM>-<NUM>.

In the development of electric vehicles, the voltage platform requirement for the cells are predetermined, which makes the volume of the cell a fixed value. That is, when a certain voltage platform is reached, the amount of materials contained in the cell is constant, and thus the volume is constant, on the basis of use of materials of the same chemical system. In the cell <NUM> according to the embodiment of the present application, by designing the ratio of the length L to the width H of the cell body <NUM>, the cell body <NUM> can be reasonably flattened and elongated at a given certain volume. On the one hand, this is conducive to the overall arrangement in the battery pack (for example, the arrangement of the battery pack <NUM> according to the above-mentioned embodiment of the present application), thereby improving the space utilization, enhancing the energy density, and thus increasing the battery life of the battery pack. On the other hand, this can ensure that the cell <NUM> has a large enough heat dissipation area to transfer the internal heat to the outside in time to prevent the heat from accumulating inside, thereby forming a higher energy density and supporting the improvement of battery life.

According to some specific embodiments of the present application, to optimize the arrangement of the cell <NUM> in the battery pack and improve the heat dissipation capacity of the cell <NUM>, the length L and the thickness D of the cell body <NUM> satisfy: L/D=<NUM>-<NUM>. In some embodiments, L/D=<NUM>-<NUM>. According to some other specific embodiments of the present application, the length L and the thickness D of the cell body <NUM> satisfy: L/D=<NUM>-<NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the cell body <NUM> is structured to have a shape of rectangular parallelepiped with a smooth outer surface to have a certain structural strength. The cell core of the cell is placed in a prismatic cell casing, the opening of the cell casing is sealed with a cover plate, and an electrolyte is injected. Compared with the cell with an aluminum laminated film, the cell <NUM> according to the embodiment of the present application has good thermal conductivity, and can effectively eliminate the problem of heat dissipation caused by a large-sized structure, when used in conjunction with a conventional battery thermal management structure. Compared with cylindrical cells, the space utilization is higher, and the production and assembly processes are simpler.

When the cell <NUM> according to the embodiment of the present application is arranged in the housing <NUM> of the battery pack <NUM>, the length direction and the thickness direction of the cell body <NUM> may extend in the horizontal directions, and the width direction of the cell body <NUM> may extend in the vertical direction. That is, the cell <NUM> stands on side. The horizontal and vertical directions are based on the direction of the battery pack <NUM> when it is used (for example, when used in an electric vehicle).

In some specific embodiments of this application, to optimize the arrangement of the cell <NUM> in the battery pack <NUM> to increase the energy density and increase the battery life, and to make the arrangement of the cell body <NUM> more compact and the energy more concentrated in the limited space of the housing <NUM>, other parameters of the cell <NUM> are designed.

According to some embodiments of the present application, the length L of the cell body <NUM> and the volume V of the cell body <NUM> satisfy: L/V= <NUM>-<NUM> - <NUM>-<NUM>. According to some embodiments of the present application, the width H of the cell body <NUM> and the volume V of the cell body <NUM> satisfy: H/V= <NUM>-<NUM>-<NUM>-<NUM>. According to some embodiments of the present application, the thickness D of the cell body <NUM> and the volume V of the cell body <NUM> satisfy: D/V= <NUM>-<NUM>-<NUM>-<NUM>. For a cell body <NUM> of a certain volume, the ratio of each of the length L, the width H, and the thickness D to the volume V can be designed to optimize the spatial distribution of unit energy, thereby facilitating the arrangement in the housing <NUM>.

In some embodiments of the present application, the length L of the cell body <NUM> and the surface area S of the cell body <NUM> satisfy: L/S= <NUM>-<NUM>-<NUM>-<NUM>. According to some embodiments of the present application, the length L of the cell body <NUM> and the energy E of the cell body <NUM> satisfy: L/E=<NUM>·Wh-<NUM> -<NUM>·Wh-<NUM>. According to some embodiments of the present application, the length L of the cell body <NUM> and the energy E of the cell body <NUM> satisfy: L/E=<NUM>·Wh-<NUM> -<NUM>·Wh-<NUM>. As such, the cell <NUM> is facilitated to extend across two opposite sides of the housing <NUM> in its length direction, thereby improving the battery life of the battery pack <NUM>, while the structural strength and heat dissipation effect of the cell <NUM> are considered.

In some other embodiments of this application, the surface area S of the cell body <NUM> and the volume V of the cell body <NUM> satisfy: S/V= <NUM>-<NUM>-<NUM>. Therefore, it is possible to ensure a sufficient heat dissipation area to ensure the heat dissipation effect, and reduce the volume ratio of the cells <NUM>, which is beneficial to the compact arrangement of a plurality of cells <NUM> in the battery pack <NUM>.

The surface area S of the cell body <NUM> and the energy E of the cell body <NUM> satisfy: S/E≤<NUM><NUM>·Wh-<NUM>. This can ensure sufficient heat dissipation on the surface of the cell <NUM>. especially when a ternary or a high-nickel ternary cathode material is employed in the power battery, the internal heat of the battery can be conducted in time, which is beneficial to the battery safety. In addition, the cell <NUM> in the embodiment of the present application is a prismatic cell with a smooth outer surface, which has a certain structural strength, and has a good thermal conductivity. Compared with a cell with a corrugated surface area, the process and subsequent assembly are less difficult.

In some specific embodiments of the present application, as shown in <FIG>, the cell <NUM> further includes a first electrode tab <NUM> and a second electrode tab <NUM>.

The first electrode tab <NUM> is provided at one end of the cell body <NUM> in the length direction, and the second electrode tab <NUM> is provided at the other end of the cell body <NUM> in the length direction. In other words, the length direction of the cell <NUM> may be the current direction inside the cell <NUM>, that is, the current direction inside the cell <NUM> is as indicated by an arrow B. In this manner, since the current direction is the same as the length direction of the cell <NUM>, the effective heat dissipation area of the cell <NUM> is larger and the heat dissipation efficiency is higher. Here, the first electrode tab <NUM> may be a positive electrode tab of the cell <NUM>, and the second electrode tab <NUM> is a negative electrode tab of the cell <NUM>; or, the first electrode tab <NUM> is the negative electrode tab of the cell <NUM>, and the second electrode tab <NUM> is the positive electrode tab of the cell <NUM>.

In some specific embodiments of the present application, as shown in <FIG>, the cell <NUM> further includes at least one anti-explosion valve <NUM>.

The at least one anti-explosion valve <NUM> is provided on at least one end of the cell body <NUM> in the length direction. When the cell <NUM> fails and expands, the gas pressure inside is enough to break through a flipping sheet in the at least one anti-explosion valve <NUM>, causing a short circuit of the cell <NUM> to ensure the safety of the cell <NUM>, and prevent the cell <NUM> from explosion.

Those skilled in the art can understand that the arrangement of the at least one anti-explosion valve <NUM> can be applied not only to a cell with an aluminum casing, but also to a pouch cell. In addition, the at least one anti-explosion valve <NUM> can also be arranged at other positions than the ends of the cell body <NUM>.

In some specific embodiments of the present application, the two ends of the cell body <NUM> in the length direction are respectively provided with an anti-explosion valve <NUM>, and the anti-explosion valves <NUM> at the two ends of the cell body <NUM> are exhausted via different exhaust passages <NUM>.

For example, as shown in <FIG>, <FIG> and <FIG>, the cell <NUM> is provided with an anti-explosion valve <NUM> at a first end facing the first side beam <NUM>, and the first side beam <NUM> is provided with exhaust passages <NUM> therein. A gas inlet <NUM> is provided at a position on the first side beam <NUM> corresponding to the anti-explosion valve <NUM> of each cell <NUM>, and the gas inlet <NUM> communicates with the exhaust passage <NUM>. The housing <NUM> is provided with an exhaust vent communicating with the exhaust passage <NUM>. And/or the cell <NUM> is provided with an anti-explosion valve <NUM> at a second end facing the second side beam <NUM>, and second side beam <NUM> is provided with exhaust passages <NUM> therein. A gas inlet <NUM> is provided at a position on the second side beam <NUM> corresponding to the anti-explosion valve <NUM> of each cell <NUM>, and the gas inlet <NUM> communicates with the exhaust passage <NUM>. The housing <NUM> is provided with an exhaust vent communicating with the exhaust passage <NUM>.

In the related art, during the use of the cell, if the gas pressure inside the cell increases to a certain degree, the anti-explosion valve is opened, so that the flame, smoke or gas inside the cell will be discharged through the anti-explosion valve. The flame, smoke or gas accumulates inside the battery pack, and if not discharged in time, will cause secondary damage to the cell. In the embodiment of the present application, since the first side beam <NUM> and/or second side beam <NUM> is/are provided with the gas inlet <NUM> corresponding to the anti-explosion valve <NUM> of the cell <NUM>, and the first side beam <NUM> and/or second side beam <NUM> is/are provided the exhaust passage <NUM> therein, the anti-explosion valve is opened when the gas pressure inside the cell <NUM> increases, and the flame, smoke or gas inside the cell will directly enter the exhaust passages <NUM> inside the first side beam <NUM> and/or the second side beam <NUM> through the gas inlet <NUM>, and will be discharged out of the first side beam <NUM> and/or the second side beam <NUM> through the exhaust vent, for example, discharged into the atmosphere through the exhaust vent. In this way, the flame, smoke or gas will not accumulate inside the battery pack <NUM>, thereby preventing the flame, smoke or gas from causing secondary damage to the cell <NUM>.

In addition, one end of each cell <NUM> in the plurality of cells <NUM> is exhausted through the exhaust passage <NUM> in the first side beam <NUM>, and the other end of each cell <NUM> in the plurality of cells <NUM> is exhausted through the exhaust passage <NUM> in the second side beam <NUM>. As a result, the two ends of the cell <NUM> are exhausted through different passages, which increases the exhaust distance and forms crossover exhaust, thereby reducing the temperature.

An electric vehicle <NUM> according to an embodiment of the present application is described below with reference to the accompanying drawings. The electric vehicle may include commercial vehicles, special vehicles, electric bicycles, electric motorcycles, electric scooters, and other electric vehicles which need to be powered by a battery pack to provide electrical energy to drive them to travel.

As shown in <FIG>, the electric vehicle <NUM> according to the embodiment of the present application includes a battery pack <NUM> according to the above-mentioned embodiment of the present application, where the housing <NUM> can be integrally formed on the electric vehicle, or the housing <NUM> can also be a separately produced vehicle tray where the cell <NUM> is accommodated and mounted.

In the electric vehicle <NUM> according to the embodiment of the present application, the battery life can be improved without expanding the space occupied by the battery by using the battery pack <NUM> according to the embodiment of the present application.

In some specific embodiments of the present application, as shown in <FIG>, the battery pack <NUM> is arranged at a bottom of the electric vehicle <NUM>, and the housing <NUM> is fixedly connected to a chassis of the electric vehicle <NUM>. Since the mounting space at the chassis of the electric vehicle <NUM> is large, when the battery pack <NUM> is provided on the chassis of the electric vehicle <NUM>, the number of cells <NUM> can be increased as many as possible, thereby increasing the battery life of the electric vehicle <NUM>.

In some specific embodiments of this application, as shown in <FIG>, the electric vehicle <NUM> includes a battery pack <NUM> arranged at a bottom of the electric vehicle <NUM>. The housing <NUM> is fixedly connected to a chassis of the electric vehicle <NUM>. The width direction of the battery pack <NUM> extends along a width direction of a vehicle body of the electric vehicle <NUM>, that is, the left and right directions of the electric vehicle <NUM>, and the length direction of the battery pack <NUM> extends along a length direction of the vehicle body of the battery pack <NUM>, that is, the front and rear directions of the electric vehicle <NUM>. In other embodiments, the electric vehicle <NUM> may include a plurality of battery packs <NUM> arranged at the bottom of the electric vehicle <NUM>, and the shape and size of the plurality of battery packs <NUM> may be the same or different. Each battery pack <NUM> can be adjusted according to the shape and size of the chassis of the electric vehicle <NUM>, and the plurality of battery packs <NUM> are arranged along the length direction, that is, the front and rear directions of the vehicle body.

In some specific embodiments of the present application, the ratio of the width F of the housing <NUM> to the width W of the vehicle body satisfies: <NUM>%≤F/W≤<NUM>%. In some other embodiments of the present application, the length L of the cell body in the width direction of the battery pack and the width W of the vehicle body satisfy: <NUM>%≤L/W≤<NUM>%. In the foregoing embodiments, this can be achieved by arranging only one housing <NUM> along the width direction of the vehicle body. When there are multiple housings <NUM>, the multiple housings <NUM> are arranged along the length direction of the vehicle body. Generally, for most vehicles, the width W of the vehicle body is <NUM>-<NUM>, for example, <NUM>, <NUM>, <NUM>, and <NUM>, and the length of the vehicle body is <NUM>-<NUM>. For a passenger vehicle, the width of the passenger vehicle is usually <NUM>-<NUM>, and the length of the vehicle body is <NUM>-<NUM>.

In some other embodiments of the present application, the width F of the housing <NUM> is <NUM>-<NUM>, which is much larger than the battery pack housing disclosed in Chinese Patent Document <CIT>, to facilitate the accommodation of the battery module <NUM> in the battery pack in <CIT>, and ensure the battery life. This size mate with the size of the vehicle body.

In some specific embodiments of the present application, the cell <NUM> includes a cell body <NUM>, where the ratio of the length L of the cell body <NUM> to the width W of the vehicle body satisfies: <NUM>%≤L/W≤<NUM>%. In this embodiment, this can be achieved by arranging only one cell <NUM> along the width direction of the vehicle body. In other possible implementations, multiple battery modules <NUM> or multiple cells <NUM> can be arranged in the length direction, while such size requirements are met. In some embodiments, the length L of the cell body <NUM> is <NUM>-<NUM>.

Other configurations and operations of the cell <NUM>, the battery pack <NUM>, and the electric vehicle <NUM> according to the embodiments of the present application are known to those of ordinary skill in the art, and will not be described in detail here.

The battery pack <NUM> according to the embodiments of the present application and the improvements in the energy density and other aspects effected by the designs of the arrangement and size parameters of the cell <NUM> are described by Comparative Embodiment <NUM>, Embodiments <NUM>-<NUM>, Comparative Embodiment <NUM> and Embodiments <NUM>-<NUM>.

In the following embodiments and comparative embodiments, description is made with lithium iron phosphate battery as an example.

In Comparative Embodiment <NUM>, Embodiment <NUM>, Embodiment <NUM>, and Embodiment <NUM>, the total volume of the battery pack <NUM>' is <NUM>, and the total volume occupied by the housing <NUM>', the internal battery management system and other power distribution modules is <NUM>. Therefore, the actual volume remaining in the battery pack <NUM>' for accommodating the cells, the width-direction transverse beam, and the length-direction transverse beam is <NUM>. The volume of the power distribution box is <NUM>, the length of the housing <NUM>' is <NUM>, the width is <NUM>, and the thickness is <NUM>. The total volume of the battery pack is <NUM>= <NUM> x <NUM> x <NUM> x <NUM> + <NUM>.

In the battery pack <NUM>' provided in the prior art, as shown in <FIG>, the housing <NUM>" is provided with two width-direction transverse beams <NUM>' and one length-direction transverse beam <NUM>' therein. The two width-direction transverse beams <NUM>' and one length-direction transverse beam <NUM>' divide the cells into six battery modules <NUM>', and each battery module <NUM>' has a battery module housing.

In the battery pack <NUM> according to this embodiment of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the width direction B of the battery pack, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM>. In the width direction B of the battery pack, the housing <NUM> accommodates two cells <NUM>. The housing <NUM> is provided with one width-direction transverse beam <NUM> and one length-direction transverse beam <NUM> therein. The width-direction transverse beam <NUM> extends along the width direction B of the battery pack <NUM>, and the plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM> to form a battery array. The width-direction transverse beam <NUM> divides the battery array into at least two parts along the length direction A of the battery pack <NUM>. In addition, the plurality of cells <NUM> are arranged into two rows of battery arrays along the width direction B of the battery pack, and the length-direction transverse beam <NUM> is located between the two adjacent rows of battery arrays. The first side beam <NUM> and the second side beam <NUM> of the housing <NUM> located at two sides of the battery pack <NUM> in the width direction B provide support for the cells <NUM>, and the first end beam <NUM> and the second end beam <NUM> of the housing <NUM> located at two ends of the battery pack <NUM> in the length direction A provide an inward pressing force against adjacent cells <NUM>. The housing <NUM> includes a layer of battery array along the height direction C of the battery pack <NUM>. The battery array (also known as battery module) of the battery pack <NUM> does not provided with end beams and side beams.

In the battery pack <NUM> according to this embodiment of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the width direction B of the battery pack, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM>. In the width direction B of the battery pack, the housing <NUM> accommodates one cell <NUM>. The cell <NUM> extends from one side to the other side of the housing <NUM> in the width direction B of the battery pack <NUM>. The housing <NUM> is provided with one width-direction transverse beam <NUM>, but no length-direction transverse beam <NUM> therein. The width-direction transverse beam <NUM> extends along the width direction B of the battery pack <NUM>, and the plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM> to form a battery array. The width-direction transverse beam <NUM> divides the battery array into two parts along the length direction A of the battery pack <NUM>. The first side beam <NUM> and the second side beam <NUM> of the housing <NUM> located at two sides of the battery pack <NUM> in the width direction B provide support for the cells <NUM>, and the first end beam <NUM> and the second end beam <NUM> of the housing <NUM> located at two ends of the battery pack <NUM> in the length direction A provide an inward pressing force against adjacent cells <NUM>. The housing <NUM> includes a layer of battery array along the height direction C of the battery pack <NUM>. The battery array (also known as battery module) of the battery pack <NUM> does not provided with end beams and side beams.

In the battery pack <NUM> according to this embodiment of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the width direction B of the battery pack, and a plurality of cells <NUM> are arranged along the length direction A of the battery pack <NUM>. In the width direction B of the battery pack, the housing <NUM> accommodates one cell <NUM>. The cell <NUM> extends from one side to the other side of the housing <NUM> in the width direction B of the battery pack <NUM>. No width-direction transverse beam <NUM> and length-direction transverse beam <NUM> are provided in the housing <NUM>. The first side beam <NUM> and the second side beam <NUM> of the housing <NUM> located at two sides of the battery pack <NUM> in the width direction B provide support for the cells <NUM>, and the first end beam <NUM> and the second end beam <NUM> of the housing <NUM> located at two ends of the battery pack <NUM> in the length direction A provide an inward pressing force against adjacent cells <NUM>. The housing <NUM> includes a layer of battery array along the height direction C of the battery pack <NUM>. The battery array (also known as battery module) of the battery pack <NUM> does not provided with end beams and side beams.

It can be known by those skilled in the art through comparison of Comparative Embodiment <NUM> and Embodiments <NUM>-<NUM> that compared with the battery pack <NUM>' in the prior art, the battery pack <NUM> according to the embodiment of the present application has a space utilization breaking through the limitations of the existing battery packs by the designs of the arrangement of the cells <NUM>, the size parameters and other factors, thereby achieving a higher energy density.

In Comparative Embodiment <NUM>, Embodiment <NUM> and Embodiment <NUM>, the total volume of the battery pack <NUM>' is <NUM>, and the total volume occupied by the housing <NUM>', the internal battery management system and other power distribution modules is <NUM>. Therefore, the actual volume remaining in the battery pack <NUM>' for accommodating the cells and/or the length-direction transverse beam and the width-direction transverse beam is <NUM>. The length of the housing <NUM>" is <NUM>, the width is <NUM>, and the thickness is <NUM>; and the cell length is <NUM>, and the width is <NUM>, and the height is <NUM>. The volume of the power distribution box is <NUM>, and the total volume of the battery pack is <NUM>=<NUM> x <NUM> x <NUM> x <NUM> + <NUM>.

In the battery pack <NUM>' provided in the prior art, as shown in <FIG>, the housing <NUM>" is provided with two width-direction transverse beams <NUM>' and one length-direction transverse beam <NUM>' therein. The two width-direction transverse beams <NUM>' and one length-direction transverse beam <NUM>' divide the cells into six battery modules <NUM>', and each battery module <NUM>' has side beams and end beams.

In the battery pack <NUM> according to this embodiment of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the length direction A of the battery pack, and a plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM>. In the length direction A of the battery pack, the housing <NUM> accommodate one cell <NUM>. The cell <NUM> extends from one side to the other side of the housing <NUM> in the length direction A of the battery pack <NUM>. The housing <NUM> is provided with one length-direction transverse beam <NUM>, but no width-direction transverse beam <NUM> therein. The length-direction transverse beam <NUM> extends along the length direction A of the battery pack <NUM>, and the plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM> to form a battery array. The length-direction transverse beam <NUM> divides the battery array into two parts along the width direction B of the battery pack <NUM>. The first end beam <NUM> and the second end beam <NUM> of the housing <NUM> located at two ends of the battery pack <NUM> in the length direction A provide support for the cells <NUM>, and the first side beam <NUM> and the second side beam <NUM> of the housing <NUM> located at two sides of the battery pack <NUM> in the width direction B provide an inward pressing force against adjacent cells <NUM>. The housing <NUM> includes a layer of battery array along the height direction C of the battery pack <NUM>. The battery array (also known as battery module) of the battery pack <NUM> does not provided with end beams and side beams.

In the battery pack <NUM> according to this embodiment of the present application, as shown in <FIG>, the length direction of the cell <NUM> is arranged along the length direction A of the battery pack, and a plurality of cells <NUM> are arranged along the width direction B of the battery pack <NUM>. In the length direction A of the battery pack, the housing <NUM> accommodates one cell <NUM>, and the cell <NUM> extends from one side to the other side of the housing <NUM> in the length direction A of the battery pack <NUM>. No width-direction transverse beam <NUM> and length-direction transverse beam <NUM> are provided in the housing <NUM>. The first end beam <NUM> and the second end beam <NUM> of the housing <NUM> located at two ends of the battery pack <NUM> in the length direction A provide support for the cells <NUM>, and the first side beam <NUM> and the second side beam <NUM> of the housing <NUM> located at two sides of the battery pack <NUM> in the width direction B provide an inward pressing force against adjacent cells <NUM>. The housing <NUM> includes a layer of battery array along the height direction C of the battery pack <NUM>. The battery array (also known as battery module) of the battery pack <NUM> does not provided with end beams and side beams.

In Comparative Embodiment <NUM>, and Embodiment <NUM>, the total volume of the battery pack <NUM>' is <NUM>, and the total volume occupied by the housing <NUM>', the internal battery management system and other power distribution modules is <NUM>. Therefore, the actual volume remaining in the battery pack <NUM>' for accommodating the cells and/or the length-direction transverse beam and the width-direction transverse beam is <NUM>. The length of the housing <NUM>' is <NUM>, the width is <NUM>, and the thickness is <NUM>. The volume of the power distribution box is <NUM>, and the total volume of the battery pack is <NUM> = <NUM> x <NUM> x <NUM> x <NUM>+<NUM>.

The arrangement of cells is the same as that in Comparative Embodiment <NUM>.

The arrangement of cells in the battery pack is the same as that in Embodiment <NUM>.

In this embodiment, the total volume of the battery pack <NUM>' is <NUM>, and the total volume occupied by the housing <NUM>', the internal battery management system and other power distribution modules is <NUM>. Therefore, the actual volume remaining in the battery pack <NUM>' for accommodating the cells and/or the length-direction transverse beam and the width-direction transverse beam is <NUM>. The length of the housing <NUM>" is <NUM>, the width is <NUM>, and the thickness is <NUM>. The volume of the power distribution box is <NUM>, and the total volume of the battery pack is <NUM> = <NUM> x <NUM> x <NUM> x <NUM> + <NUM>. The arrangement of cells in the battery pack is the same as that in Embodiment <NUM>.

The specific parameters of Embodiments <NUM>-<NUM>, and Comparative Embodiments <NUM>-<NUM> are shown in Table <NUM>. The total cell volume is the sum of the volumes of multiple cells; the volume of the battery pack is the overall volume of a three-dimensional shape defined by an external profile of the battery pack, that is, the volume of the three-dimensional area enclosed in space by the external profile of the battery pack; and the volume of the cell accommodating cavity is the volume of the accommodating space defined in the housing.

It can be known by those skilled in the art through comparison of the comparative embodiments and the embodiments of the present application that the battery pack <NUM> according to the embodiment of the present application has a space utilization breaking through the limitations of the existing battery packs by the designs of the arrangement of the cells <NUM>, the size parameters and other factors, thereby achieving a higher energy density. Moreover, this increase in the energy density will be enlarged as the overall volume of the battery pack increases. That is, for a battery pack with a larger volume, the improvement in energy density effected by the solution in the embodiments of this application is more significant.

In description of this specification, description of reference terms such as "specific embodiments", or "specific examples", means including specific features, structures, materials, or features described in the embodiment or example in at least one embodiment or example of this application. In this specification, exemplary descriptions of the foregoing terms do not necessarily refer to the same embodiment or example.

Claim 1:
A battery pack (<NUM>), comprising:
a housing (<NUM>);
a plurality of cells (<NUM>), provided in the housing (<NUM>);
wherein the sum V1 of the volumes of the plurality of cells (<NUM>) and the volume V2 of the battery pack (<NUM>) satisfy V1/V2≥<NUM>%; and
the battery pack (<NUM>) has a first direction and a second direction perpendicular to each other; a length direction of the cell (<NUM>) is arranged along the first direction of the battery pack (<NUM>), and the plurality of cells (<NUM>) are arranged along the second direction of the battery pack (<NUM>); the housing (<NUM>) accommodates only one cell (<NUM>) along the first direction; and the cell (<NUM>) comprises a cell body (<NUM>), and the length of the cell body (<NUM>) is <NUM>-<NUM>.