Patent Description:
The battery pack generally includes a housing, a battery cell assembly disposed in the housing, and a circuit board for controlling the state of charging and discharging of the battery pack. During the use of the battery pack, the battery cell assembly continuously releases heat. When the temperature of the battery cell assembly reaches the temperature value of the thermal protection for the battery cell, the battery pack will stop discharging under the control of the circuit board.

Current battery cell assemblies are usually composed of a plurality of cells to form an array. The battery cell located at the edge of the array dissipates heat quickly, while the battery cell located at the center of the array dissipates heat slowly, or even fails to dissipate heat effectively, so that the battery cell at the center of the battery cell assembly reaches the temperature value of the thermal protection for the battery cell fastest, which triggers the protection mechanism of the battery pack, the circuit board controls the battery pack to stop discharging, thereby affecting the normal use of the battery pack and reducing the user experience. For example, <CIT> discloses a battery packing module. <CIT> discloses a multi-cell battery pack system. <CIT> discloses a cooling structure of a battery cell. <CIT> discloses a battery pack.

In view of the above problems, it is necessary to provide a battery pack to solve the above problems.

The object of the present invention is to provide a battery pack, which assists the heat dissipation of the battery cell assembly through a heat dissipation assembly, which not only can make the temperature of each area of the battery cell assembly more balanced, but also effectively extend the working time of the battery cell assembly and reduce the decay rate of the battery cell assembly, thereby effectively extending the service life of the battery pack.

In order to achieve the above object, the present invention provides a battery pack, which comprises: a battery cell assembly comprising a battery cell array composed of a plurality of cylindrical battery cells and a channel provided in the battery cell array, the channel being formed by N surrounding battery cells, wherein N > <NUM>; and a heat dissipation assembly comprising a heat-absorbing member disposed in the channel, and wherein the heat-absorbing member comprises N side walls, wherein the N side walls respectively abut against the side walls of the N battery cells, the heat dissipation assembly comprises a heat-conducting member in contact with the heat-absorbing member to dissipate the heat absorbed by the heat-absorbing member, wherein the heat-conducting member is disposed along an axial direction of the battery cell, and the heat-conducting member is partially located inside the heat-absorbing member and partially located outside the heat-absorbing member and wherein the heat-conducting member comprises a cylinder provided with a receiving groove and a plurality of heat dissipation fins, wherein the receiving groove is provided along an axial direction of the cylinder, and one end of the heat dissipation fins are installed on the sidewall of the receiving groove, and the other end extends into the receiving groove, the heat-absorbing member is provided with a receiving cavity for accommodating the cylinder.

In one embodiment, the battery pack further comprises a housing for accommodating the battery cell assembly and the heat dissipation assembly, wherein the heat-conducting member is in contact with the housing.

In one embodiment, the battery pack further comprises a housing for accommodating the battery cell assembly and the heat dissipation assembly, the housing is provided with a ventilation hole that cooperates with the heat dissipation assembly, so as to dissipate heat by air convection.

In one embodiment, the heat-absorbing member is made of a shape-stabilized phase change material.

In one embodiment, the heat-absorbing member comprises a phase change material and a heat-conducting shell accommodating the phase change material.

In order to achieve the above object, the battery pack further comprises: a frame, wherein the frame is provided with a receiving portion to receive the battery cells, the receiving portion comprising a first receiving portion for receiving the N battery cells, wherein the heat-absorbing member in the heat dissipation assembly being disposed in the first receiving portion, and the N battery cells are located between the heat-absorbing member and the sidewalls of the first receiving portion.

The beneficial effect of the present invention is that the battery pack of the present invention assists the heat dissipation of the battery cell assembly through the heat dissipation assembly, which can not only make the temperature of each area of the battery cell assembly more balanced, but also effectively extend the working time of the battery cell assembly and reduce the decay rate of the battery cell assembly, thereby effectively prolonging the service life of the battery pack.

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail below with reference to the drawings and specific embodiments.

Please refer to <FIG> and <FIG>, the present invention discloses a battery pack <NUM> comprising a housing <NUM>, a battery cell assembly <NUM>, a heat dissipation assembly <NUM> that cooperates with the battery cell assembly <NUM>, and a circuit board <NUM> for controlling the battery pack <NUM> in the charged and discharged state. The battery cell assembly <NUM>, the heat dissipation assembly <NUM>, and the circuit board <NUM> are accommodated in the housing <NUM>.

Please refer to <FIG> and <FIG>, the housing <NUM> comprises a top wall <NUM>, a bottom wall <NUM> opposite to the top wall <NUM>, and a side wall <NUM> perpendicular to the top wall <NUM>. The top wall <NUM>, the bottom wall <NUM>, and the side wall <NUM> are put together to form a receiving space for receiving the battery cell assembly <NUM>, the heat dissipation assembly <NUM>, and the circuit board <NUM>.

Please refer to <FIG>, <FIG> and <FIG>, the battery cell assembly <NUM> comprises a battery cell array <NUM> and a frame <NUM> that receives the battery cell array <NUM>. Please refer to <FIG>, the battery cell array <NUM> is composed of a plurality of battery cells <NUM> arranged in a certain form. A channel <NUM> is provided in the battery cell array <NUM>, which is surrounded by N battery cells <NUM> forming the channel <NUM>, where N is an integer greater than <NUM>. In this embodiment N is <NUM>. Please refer to <FIG>, in this embodiment the channel <NUM> is formed by canceling one battery cell <NUM> in the battery cell array <NUM>, that is the channel <NUM> is formed by taking out the battery cell <NUM> in the battery cell array <NUM> where the maximum heat is generated. The heat dissipation assembly <NUM> disposed at the highest heating point in the battery cell array <NUM> can not only quickly reduce the internal temperature of the battery pack <NUM>, but also this cooling method has the highest efficiency and remarkable effect. Of course, the channel <NUM> may also have other structural forms. For example, <FIG> illustrates a channel <NUM> ' (dashed line portion) surrounded by three battery cells <NUM>. <FIG> illustrates a channel <NUM>" surrounded by four battery cells <NUM>" (dashed line portion). In this embodiment, the battery cell array <NUM> is provided with one channel <NUM>, but in other embodiments, the size and number of the channel <NUM> can be set as required. For example, the battery cell array <NUM> is provided with two or more channels <NUM>, as shown in <FIG> and <FIG>. It can be understood that, in this embodiment, the cross-sectional shape of the battery cell <NUM> is circular. However, in other embodiments, the cross-sectional shape of the battery cell <NUM> may be set as required, such as regular polygon. Please refer to <FIG>, the frame <NUM> is provided with a receiving portion <NUM> to receive the battery cell array <NUM>. The receiving portion <NUM> comprises a first receiving portion <NUM> and a second receiving portion <NUM>. The channel <NUM> surrounded by the N battery cells <NUM> and these N battery cells <NUM> are received in the first receiving portion <NUM>. The second receiving portion <NUM> is used to receive a single battery cell <NUM>. In this embodiment, the second receiving portion <NUM> is used to receive a single battery cell, but in other embodiments, the second receiving portion <NUM> may also be configured to receive multiple battery cells <NUM>. In this embodiment, the receiving portion <NUM> has two specifications: a first receiving portion <NUM> that accommodates six battery cells <NUM>, and a second receiving portion <NUM> that accommodates a single battery cell <NUM>. However, in other embodiments, the specifications of the receiving portion <NUM> may be provided in various types as required, for example, one receiving portion for receiving six battery cells <NUM>, one receiving portion for receiving three battery cells <NUM>, or multiple receiving portions for receiving a single battery cell <NUM>.

Please refer to <FIG> and <FIG>, the heat dissipation assembly <NUM> received in the channel <NUM> comprises a heat-absorbing member <NUM> and a heat-conducting member <NUM> in contact with the heat-absorbing member <NUM>. The structure of the heat dissipation assembly <NUM> shown in <FIG> is not part of the present invention. The heat-absorbing member <NUM> comprises N sidewalls <NUM>. The N sidewalls <NUM> respectively abut against the side walls of the N battery cells <NUM> so that the heat-absorbing member <NUM> absorbs the heat from the N battery cells <NUM>, and the battery cells <NUM> can quickly dissipate heat and cool down. In this embodiment, the side wall <NUM> have an arc-shaped wall, and its radian matches the radian of the side wall of the battery cell <NUM>. In this embodiment, the heat-absorbing member <NUM> is made of a shape-stabilized phase change material. However, in other embodiments, the heat-absorbing member <NUM> may also comprise the phase change material and a heat-conducting shell accommodating the phase change material, and the phase change material may be shaped or amorphous. The heat-conducting shell is made of a material with high thermal conductivity. It can be understood that the heat-absorbing member <NUM> may also be made of other materials capable of achieving a heat absorbing function, which is not specifically limited in the present invention. The heat-conducting member <NUM> is used to conduct the heat absorbed by the heat-absorbing member <NUM> and dissipate the heat to the outside environment, the heat-conducting member <NUM> can improve the heat-absorbing efficiency of the heat-absorbing member <NUM>. The heat-conducting member <NUM> may be made of metal, high thermally conductive plastic, ceramic, or the like. The heat-conducting member <NUM> is disposed along the axial direction of the battery cell <NUM> and is partially located inside the heat-absorbing member <NUM> and partially located outside the heat-absorbing member <NUM>. In this embodiment, the heat-conducting member <NUM> is cylindrical, and penetrates the heat-absorbing member <NUM> along the axial direction of the battery cell <NUM>. Both ends of the heat-conducting member <NUM> may be respectively connected to the top wall <NUM> and the bottom wall <NUM> or may not be in contact with the top wall <NUM> and the bottom wall <NUM>.

<FIG> shows a heat dissipation assembly <NUM> according to a second embodiment. The structure of the heat dissipation assembly <NUM> shown in <FIG> is not part of the present invention. The heat dissipation assembly <NUM> comprises a heat-absorbing member <NUM> and a heat-conducting member <NUM> in contact with the heat-absorbing member <NUM>. The structure of the heat-absorbing member <NUM> is substantially the same as that of the heat-absorbing member <NUM>. The heat-conducting member <NUM> comprises a first heat-conducting member <NUM> and a second heat-conducting member <NUM>. One end of the first heat-conducting member <NUM> is fixed on the top wall <NUM>, and the other end is inserted into the heat-absorbing member <NUM>. One end of the second heat-conducting member <NUM> is fixed on the bottom wall <NUM>, and the other end is inserted into the heat-absorbing member <NUM>. In this embodiment, the heat-conducting member <NUM> is a split type, but it can be understood that in other embodiments, the first heat-conducting member <NUM> and the second heat-conducting member <NUM> may form a whole, and one end is fixed to the top wall <NUM> or the bottom wall <NUM> and the other end is inserted into the heat-absorbing member <NUM>.

<FIG> shows a heat dissipation assembly <NUM> according to a third embodiment. The structure of the heat dissipation assembly <NUM> shown in <FIG> is not part of the present invention. The structure of the heat dissipation assembly <NUM> is substantially the same as that of the heat dissipation assembly <NUM>. The heat dissipation assembly <NUM> comprises a heat-absorbing member <NUM> and a heat-conducting member <NUM> in contact with the heat-absorbing member <NUM>. The difference is that the heat-conducting member <NUM> is a heat conducting sheet, that is, the heat-conducting member <NUM> comprises a first heat-conducting sheet and a second heat-conducting sheet, the first heat-conducting sheet and the second heat-conducting sheet are substantially the same as the first heat-conducting member <NUM> and the second heat-conducting member <NUM>. In this embodiment, one end of the heat-conducting member <NUM> is inserted into the heat-absorbing member <NUM>, but it can be understood that in other embodiments, the heat-conducting member <NUM> further comprises a heat conductor that penetrates the heat-absorbing member <NUM> along the axial direction of the battery cell <NUM>, and two ends of the heat conductor protrude from the two ends of the heat-absorbing member <NUM> respectively, the other end of the first heat-conducting sheet and the other end of the second heat-conducting sheet are respectively inserted into the cylindrical heat conductor.

<FIG> shows a heat dissipation assembly <NUM> according to a fourth embodiment. The heat dissipation assembly <NUM> comprises a heat-absorbing member <NUM> and a heat-conducting member <NUM> in contact with the heat-absorbing member <NUM>. The heat-absorbing member <NUM> has the same structure as the heat-absorbing member <NUM>, and a receiving cavity <NUM> is provided therein. The heat-conducting member <NUM> comprises a hollow cylinder <NUM> and a plurality of heat dissipation fins <NUM>. The cylinder <NUM> is disposed in the receiving cavity <NUM> and abuts against the side wall of the receiving cavity <NUM>. The cylinder <NUM> is provided with a receiving groove <NUM>, in this embodiment, the hollow part of the cylinder forms the receiving groove <NUM>. One end of the heat dissipation fins <NUM> are installed on the sidewall of the receiving groove <NUM>, and the other end extends into the receiving groove <NUM>. It can be understood that the top wall <NUM> and the bottom wall <NUM> may further be provided with a ventilation hole (not shown) that cooperates with the heat dissipation assembly <NUM> so as to dissipate heat by air convection.

<FIG> shows a heat dissipation assembly <NUM> according to a fifth embodiment. The structure of the heat dissipation assembly <NUM> shown in <FIG> is not part of the present invention. The heat dissipation assembly <NUM> comprises a heat-absorbing member <NUM> and a heat-conducting member <NUM> in contact with the heat-absorbing member <NUM>. The structure of the heat-absorbing member <NUM> is substantially the same as that of the heat-absorbing member <NUM>. A receiving cavity <NUM> is provided in the heat-absorbing member <NUM> to receive the heat-conducting member <NUM>. The heat-conducting member <NUM> comprises a shaft body <NUM> disposed along the axial direction of the battery cell <NUM> and a plurality of heat dissipation fins <NUM> disposed on the shaft body <NUM>. The heat dissipation fins <NUM> are disposed on the arc-shaped sidewall of the shaft body <NUM>. In this embodiment, the plurality of heat dissipation fins <NUM> have a total of eight rows, and each row of heat dissipation fins <NUM> form a straight line parallel to the axis of the shaft body <NUM>. However, it can be understood that the line formed by the dissipation fins <NUM> in each row may also be a spiral line rotating around the shaft body <NUM>.

Compared with the prior art, the battery pack <NUM> of the present invention assists the heat dissipation of the battery cell assembly <NUM> through the heat dissipation assembly <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, which can not only make the temperature of each area of the battery cell assembly <NUM> more balanced, but also can effectively extend the working time of the battery cell assembly <NUM> and reduce the attenuation speed of the battery cell assembly <NUM>, thereby effectively prolonging the service life of the battery pack <NUM>.

Claim 1:
A battery pack (<NUM>), which comprises:
a battery cell assembly (<NUM>) comprising a battery cell array (<NUM>) composed of a plurality of cylindrical battery cells (<NUM>) and a channel (<NUM>) provided in the battery cell array (<NUM>), the channel (<NUM>) being formed by N surrounding battery cells (<NUM>), wherein N > <NUM>; and
a heat dissipation assembly (<NUM>) comprising a heat-absorbing member (<NUM>) disposed in the channel (<NUM>), and wherein the heat-absorbing member (<NUM>) comprises N side walls (<NUM>), wherein the N side walls (<NUM>) respectively abut against the side walls of the N battery cells (<NUM>),
the heat dissipation assembly (<NUM>) comprises a heat-conducting member (<NUM>,) in contact with the heat-absorbing member (<NUM>) to dissipate the heat absorbed by the heat-absorbing member (<NUM>), wherein
the heat-conducting member (<NUM>) is disposed along an axial direction of the battery cell (<NUM>), and the heat-conducting member (<NUM>) is partially located inside the heat-absorbing member (<NUM>) and partially located outside the heat-absorbing member (<NUM>) and wherein
the heat-conducting member (<NUM>) comprises a cylinder (<NUM>) provided with a receiving groove (<NUM>) and a plurality of heat dissipation fins (<NUM>), wherein the receiving groove (<NUM>) is provided along an axial direction of the cylinder (<NUM>), and one end of the heat dissipation fins (<NUM>) are installed on the sidewall of the receiving groove (<NUM>), and the other end extends into the receiving groove (<NUM>), the heat-absorbing member (<NUM>) is provided with a receiving cavity (<NUM>) for accommodating the cylinder (<NUM>).