CN112397805A

CN112397805A - Battery pack with heat dissipation function

Info

Publication number: CN112397805A
Application number: CN201910752783.1A
Authority: CN
Inventors: 傅世泽; 谢祥谦
Original assignee: Taipu Power New Energy Changshu Co ltd
Current assignee: Taipu Power New Energy Changshu Co ltd
Priority date: 2019-08-15
Filing date: 2019-08-15
Publication date: 2021-02-23

Abstract

The invention provides a battery pack with a heat dissipation function, which comprises a battery module. The battery module includes a plurality of battery cells and a serpentine separator. The zigzag partition board is arranged between the two battery cores, the zigzag partition board and the battery cores define a plurality of channels for a fluid to flow through the channels, so that the fluid directly contacts the parts of the battery cores defining the channels to conduct heat to the battery cores.

Description

Battery pack with heat dissipation function

Technical Field

The present invention relates to a battery pack, and more particularly, to a battery pack having a heat dissipation function.

Background

In the charging and discharging process of a general battery, the temperature of a battery body rises due to the operation of electrons in a filling material, and when the temperature rises continuously and exceeds the temperature of a battery working interval, the temperature has great influence on the power supply efficiency of the battery body and the service life of the battery, so that the generated heat energy needs to be taken away, the heat of the battery is dissipated, and the battery can be kept to operate at the temperature of the normal working interval. The heat conduction manner of the battery in the prior art is exemplified as follows. One current structure is that the air current only passes through battery core (Cell) side banding region, can't effectively dispel the heat and the samming control to the battery, and another current structure just can form the wind channel for needing two cooling plates and relevant bearing structure, and not only the structure is complicated, with high costs, and the maintenance is difficult.

Chinese patent publication No. CN101076240A discloses a heat dissipation structure of a battery. Fig. 1 shows a schematic view of a structure of a battery module of the known art. As shown in fig. 1, a known cooling and heat dissipating structure for energy storage devices such as super capacitors and batteries includes a battery core 102, heat dissipation fins 101 having the same shape as the battery core 102 are sleeved around the periphery of the battery core 102, the interior of the heat dissipation fins 101 is made into a relatively smooth plane, the joint surfaces of the heat dissipation fins 101 and the battery core 102 are tightly combined, the height dimension of the heat dissipation fins 101 is smaller than the height dimension of the casing of the battery core 102, the outer sides of the two ends of the heat dissipation fins 101 are made into a transverse convex-concave shape, when a plurality of battery cores 102 are combined together, the protruding portions of the heat dissipation fins 101 are just opposite to each other in sequence. When a plurality of battery cells 102 are combined into a battery module, the periphery of the battery module is provided with shutters to form a capacitor bin, and a fan is arranged above the capacitor bin.

Lithium polymer batteries (Li-polymers) have evolved from lithium ion batteries. For example, chinese patent No. CN205355199U discloses a lithium polymer battery. Commercial lithium polymer batteries produced today are laminated packages in the form of flexible, soft films, unlike cylindrical lithium ion batteries having metal hard shells. The hard case of the lithium ion battery needs to provide a pressure for fixing the insulator and the electrode together, while the package of the lithium polymer battery does not need such a pressure since the electrode tabs and the insulator are stacked on each other. Such a battery pack may reduce the weight by 20% over the hard cell itself due to the lack of a metal hard shell.

However, when a plurality of lithium polymer batteries are combined into one battery, there is a problem of how to perform heat dissipation efficiently.

Disclosure of Invention

An object of an embodiment of the present invention is to provide a battery pack that performs heat dissipation using a meandering partition plate.

According to an embodiment of the present invention, a battery pack includes a battery module. The battery module comprises a plurality of battery cells and at least one zigzag separator. The at least one zigzag partition board is respectively arranged on one side surface of the plurality of battery cores, and the at least one zigzag partition board and the plurality of battery cores define a plurality of channels for a fluid to flow through the plurality of channels, so that the fluid directly contacts the parts of the plurality of battery cores defining the plurality of channels to conduct heat to the plurality of battery cores.

In one embodiment, the at least one meandering partition is made of a thermally conductive material, thereby increasing the thermal conductivity and accelerating the efficiency of the fluid in conducting heat to the plurality of battery cells.

In one embodiment, the at least one zigzag partition is shaped as a square wave or a circular arc wave.

In one embodiment, the plurality of battery cells includes a flexible package, and at least a portion of the flexible package protrudes into the plurality of channels.

In one embodiment, at least another portion of the flexible package body of the plurality of battery cells is flatly attached to a supporting region of the at least one zigzag partition.

In one embodiment, the battery module further includes an intermediate layer between a support region of the at least one serpentine separator plate and the plurality of battery cells.

In one embodiment, the plurality of battery cells further includes at least one electrode disposed on a first side of the plurality of battery cells. And the width of the channel of the at least one zigzag partition plate near the at least one electrode side is larger than the width of the channel of the at least one zigzag partition plate far from the at least one electrode side; or the thickness of the at least one zigzag partition plate near the channel of the at least one electrode side is larger than that of the at least one zigzag partition plate far from the channel of the at least one electrode side.

In one embodiment, the battery pack further includes a fan and a housing. The fan is used for generating an air flow as the fluid. The casing is used for accommodating the fan and the battery module. The fan is arranged on the side surface of the battery module, so that the airflow passes through the plurality of channels, and the extending direction of the channels is approximately parallel to the advancing direction of the airflow.

In one embodiment, the at least one zigzag partition plate is a molded body.

An embodiment of the present invention is directed to economically and efficiently conducting heat (heating or dissipating heat) to a battery pack, so that the battery pack can operate at a temperature in a normal operating region thereof, and reducing a temperature difference between battery cells to maintain good power supply efficiency and battery life.

Drawings

Fig. 1 shows a schematic view of a structure of a battery module of the known art.

Fig. 2 is a schematic diagram illustrating a structure of a battery module according to an embodiment of the present invention.

Fig. 3A is a schematic view illustrating a structure of a battery module according to another embodiment of the present invention.

Fig. 3B is a schematic view illustrating a structure of a battery module according to another embodiment of the present invention.

Fig. 4 is a schematic diagram illustrating a battery pack structure according to an embodiment of the present invention.

Reference numerals:

101: heat sink

102: battery core

103: air duct

200: battery pack

201: zigzag partition plate

201a, 201 b: part of a meandering partition

202: battery core

202 a: first battery core

202 b: second battery core

203. 203a, 203 b: channel

204: electrode for electrochemical cell

205: zigzag partition plate

207: intermediate layer

210: battery module

212: soft package

220: fan with cooling device

221: support zone

230: shell body

Detailed Description

An embodiment of the present invention is directed to economically and efficiently conducting (heating or dissipating) heat to a Battery Pack (Battery Pack), so that the Battery Pack can operate at a temperature within a normal operating range thereof, and reducing a temperature difference between cells to maintain good power supply efficiency and Battery life. Fig. 2 shows a schematic diagram of a battery module (module) structure according to an embodiment of the invention. To achieve the above objective, as shown in fig. 2, in one embodiment, the battery module 210 includes one or more zigzag separators 201, at least one battery cell 202, and a plurality of channels 203. In one embodiment, the battery module 210 may also include a serpentine separator 205, wherein the serpentine separator 205 has a shape different from the shape of the serpentine separator 201. In one embodiment, the zigzag separator 201 is a molded body, and the

zigzag separator

201 or 205 is disposed on one side of the battery cell 202, and more specifically, in one embodiment, is disposed on the outer surface of the package body of the battery cell 202. The serpentine separators 201 and the battery cells 202 (more specifically, the outer surfaces of the flexible packages 212 of the battery cells 202) form a plurality of channels 203 for fluid to flow through the plurality of channels 203, thereby allowing the fluid to directly contact portions of the plurality of battery cells 202 defining the plurality of channels 203 in addition to the

serpentine separators

201 or 205 to conduct heat to the battery cells 202, such as heat or heat dissipation. The spirit of the present invention will be described below with respect to heat dissipation. The heating section is self-explanatory and can be modified or changed by those skilled in the art in light of the following description.

In one embodiment, the plurality of battery cells 202 includes a first battery cell 202a and a second battery cell 202 b. The plurality of channels 203 includes a plurality of channels 203 a. The serpentine separator 201 is disposed between the first battery cell 202a and the second battery cell 202b, the serpentine separator 201 and the first battery cell 202a defining a plurality of channels 203 a. As shown in fig. 2, the fluid directly contacts portions of the first battery cell 202a defining the plurality of channels 203a to conduct heat to the first battery cell 202 a. At least a portion 201a of the serpentine separator 201 defining the plurality of channels 203a is in thermally conductive contact with the second battery cell 202 b. In one embodiment, at least a portion 201a of the serpentine separator 201 may be in thermally conductive contact with a second cell 202b (described below) via an intermediate layer 207.

In one embodiment, the plurality of channels 203 further comprises a plurality of channels 203 b. The serpentine separator 201 and the second battery cell 202b define a plurality of channels 203 b. As shown in fig. 2, the fluid directly contacts portions of the second battery cell 202b defining the plurality of channels 203b to conduct heat to the second battery cell 202 b. Also, at least a portion 201b of the serpentine separator 201 defining the plurality of channels 203b is in thermally conductive contact with the first battery cell 202 a. In one embodiment, at least a portion 201b of the serpentine separator 201 may be in thermally conductive contact with a second cell 202b (described below) via an intermediate layer 207.

In one embodiment, the meandering partition 201 may be made of a thermally conductive material to increase the thermal conductivity and speed up the heating or heat dissipation efficiency of the fluid on the battery cell 202. The zigzag partition plate can be shaped into square waves (zigzag partition plate 201) or arc waves (zigzag partition plate 205) to balance the support stress area and the heat dissipation contact area. Unlike the conventional battery cell 202 in which heat is dissipated by heat dissipation via a heat sink and then conducted to the air, the battery cell 202 according to an embodiment of the present invention can conduct heat to the air via the bent partition 201 as a heat sink, and the outer surface of the package of the battery cell 202 directly conducts heat convection with the air, so that the battery cell 202 has excellent heat dissipation effect and a simple structure.

In one embodiment, the battery cell 202 includes a flexible package 212, and for example, the battery cell 202 can be a lithium polymer battery, and many of the currently commercially available lithium polymer batteries are packaged by the flexible package 212. In this case, as shown in the partially enlarged view of the battery cell of fig. 2, the soft package 212 may slightly protrude into the channel 203 at the portion of the channel 203, so that the soft package 212 may be in closer contact with the support region 221 at the portion of the support region 221 of the meandering separator 201, thereby increasing the efficiency of contact heat conduction. In one embodiment, at least a portion 201a or 201b of the zigzag partition 201 is a support region 221.

According to the known art, the heat dissipation is increased by tightly bonding the bonding surfaces of the heat sink 101 and the battery cell 102. However, when the case of the battery cell 102 is made of a soft material, since there is no buffer space, a plurality of small spaces which are sealed or poor in air circulation are easily formed between the soft case of the battery cell 102 and the heat dissipation fins 101, and since air is not a good heat conductor, the heat dissipation effect is reduced. To improve this, the

serpentine separators

201 or 205 are arranged according to the invention so as to form a plurality of channels 203 with the battery cells 202, and so that the fluid can directly contact the portions of the plurality of battery cells 202 that define the plurality of channels 203 in addition to the

serpentine separators

201 or 205.

In the channel 203 region, since the fluid directly contacts the surfaces of the plurality of battery cells 202, convection heat dissipation can be directly performed, and a good direct heat dissipation effect is achieved. In the supporting region 221 of the zigzag partition 201, the heat generated by the battery cell 102 is conducted to the zigzag partition 201 by a contact heat conduction manner, so as to increase the heat dissipation area, thereby having a better indirect heat dissipation effect. In addition, since the buffer space is formed in the channel 203 so that the soft package 212 can protrude into the channel 203, the adhesion between the support section 221 and the soft package 212 is increased, and the thermal contact conduction efficiency between the support section 221 and the soft package 212 is increased. Therefore, compared with the prior art, the heat sink has better overall heat dissipation effect.

In one embodiment, the zigzag partitions can be shaped as square waves (zigzag partitions 201) or arc waves (zigzag partitions 205), so that the soft package 212 can be supported in the supporting region 221, and the balance can be achieved: the flexible package 212 is supported by the support region 221 in a force bearing area, a thermal contact area with the support region 221, and an area in direct contact with the fluid in the channel 203. In the present embodiment, the design can be performed for different areas, so that there are more heat dissipation factors to be used when designing the product, which facilitates individual design or customization for different products. According to an embodiment of the present invention, a better or optimized state of heat dissipation can be found among the three areas according to various material properties.

As shown in FIG. 2, in one embodiment, the width w of the channel 203 of the zigzag partition 201 is 10mm and the height is 3 mm. In one embodiment, the width of the channel 203 as an air channel is 9.6mm, which is obtained by optimization simulation analysis, and can simultaneously satisfy the requirements of reducing the air pressure and uniformly supporting the battery cells 202. In one embodiment, the high temperature of the plurality of battery cells 202 is within 4 ℃ and the low temperature is within 3 ℃ by optimization simulation analysis. While the temperature difference of a single cell 202 is 12 deg.c. In another embodiment, the plurality of battery cells 202 have a temperature difference of 4 ℃ and a temperature difference of 5 ℃. While the temperature difference of a single cell 202 is 11 deg.c. Therefore, according to the structure of the embodiment of the invention, the flow rate of the air flow can effectively carry away the heat of each battery cell 202.

Further, when the zigzag baffles 205 are formed in a circular arc shape wave, the average channel width of the zigzag baffles 205 may be 10mm or 9.6 mm. In one embodiment, it is preferred that the cross-sectional area of each channel 203 be about 10mm by 3mm or 9.6mm by 3 mm.

As shown in fig. 2, the battery module 210 further includes an intermediate layer 207, the intermediate layer 207 being located between a support region 221 of the serpentine separator 201 and the battery cell 202. Since the soft package 212 is made of a soft material, it is easily broken by a sharp object or a rough surface, and the intermediate layer 207 can protect the soft package 212. In one embodiment, the intermediate layer 207 may be a thermal conductive paste, which can increase the thermal contact heat dissipation effect in addition to the protection effect.

Fig. 3A is a schematic view illustrating a structure of a battery module according to another embodiment of the present invention. Fig. 3B is a schematic view illustrating a structure of a battery module according to another embodiment of the present invention. As shown in fig. 3A and 3B, in one embodiment, the battery cell 202 includes at least one electrode 204, for example, two electrodes 204 are respectively used as a positive electrode and a negative electrode. The electrodes 204 are disposed on a first side of the battery cell 202 and protrude outward for connecting to an external conductive circuit.

Because the heat generation of the battery Cell 202 is uneven, the local high temperature is generated due to the violent chemical reaction at the tab of the electrode 204, and the air duct width of the channel 203 can be adjusted by the

zigzag partition

201 or 205 to adjust the air speed or air volume flowing through, or the local material improves the heat conductivity or thickness, so that the heat can be dissipated more quickly at the high temperature of the battery Cell (Cell)202, for example, at the tab end of the electrode 204, thereby achieving the temperature equalization effect of the battery Cell 202.

As shown in fig. 3A, the width of a channel 203 of the meandering partition 201 on the side close to the electrode 204 is larger than the width of a channel 203 of the meandering partition 201 on the side away from the electrode 204. Therefore, the heat dissipation effect is better for the portion of the battery cell 202 near the electrode 204, so as to achieve the effect of temperature equalization of the battery cell 202.

As shown in fig. 3B, the thickness of the meandering partition 201 of a channel 203 near the electrode 204 side is greater than the thickness of the meandering partition 201 of a channel 203 at the side far from the electrode 204. Therefore, the heat dissipation effect is better for the portion of the battery cell 202 near the electrode 204, so as to achieve the effect of temperature equalization of the battery cell 202.

Fig. 4 is a schematic diagram illustrating a battery pack structure according to an embodiment of the present invention. As shown in fig. 4, in one embodiment, the battery pack 200 includes a battery module 210, at least one fan 220, and a housing 230. The battery module 210 and the at least one fan 220 are disposed in the housing 230. The at least one fan 220 is disposed at a side of the battery module 210, such that an airflow generated by the fan 220 flows into the plurality of channels 203. As shown in fig. 2, the extending direction of the passage 203 is substantially parallel to the traveling direction D of the air flow (the direction D represents a normal direction on the paper surface).

In one embodiment, the

zigzag partition

201 or 205 can adjust the air speed or air volume flowing through by adjusting the width of the air duct, so as to rapidly take away heat from the high temperature of the battery core 202, such as the tab end, to achieve uniform temperature. In this embodiment, the heat dissipation design factor is increased, so that the effect of conveniently designing the heat dissipation parameters or structures is achieved. In one embodiment, computer software can be used to calculate the overall heat dissipation effect generated by various heat dissipation parameters to obtain a better heat dissipation state. In one embodiment, the

zigzag separator

201 or 205 can improve the thermal conductivity or thickness by adjusting the local material of the air channel, so as to more rapidly carry heat away from the high temperature of the battery core 202, such as the tab end, to achieve uniform temperature.

As described above, according to an embodiment of the present invention, the zigzag separator 201 and the outer surface of the package of the battery cell 202 form a plurality of channels 203 for fluid to flow through the plurality of channels 203, so that the fluid directly contacts the surfaces of the plurality of channels 203 defined by the zigzag separator 201 and the battery cell 202 to heat or dissipate heat from the battery cell 202. Therefore, the heat conduction (heating or heat dissipation) of the battery cells can be economically and efficiently performed, so that the battery pack can operate at the temperature of the normal operating region thereof, and the temperature difference between the battery cells is reduced to maintain good power supply efficiency and battery life.

Claims

1. A battery pack with heat dissipation function, comprising a battery module, wherein the battery module comprises:

a first battery cell and a second battery cell; and

a zigzag separator disposed between the first battery cell and the second battery cell, the zigzag separator and the first battery cell defining a plurality of channels for a fluid to flow through the plurality of channels,

wherein the content of the first and second substances,

the fluid directly contacts the portion of the first battery cell defining the plurality of channels to conduct heat to the first battery cell, and

at least a portion of the serpentine separator plate defining the plurality of channels is in thermally conductive contact with the second battery cell.

2. The battery of claim 1, wherein the serpentine separator is made of a thermally conductive material to increase the thermal conductivity and accelerate the efficiency of the fluid in conducting heat to the first and second cells.

3. The battery of claim 1, wherein the shape of the zigzag partition is a square wave or a circular arc wave.

4. The battery pack according to any one of claims 1 to 3, wherein the first battery cell and the second battery cell comprise a flexible package, at least a portion of the flexible package protruding into the plurality of channels.

5. The battery pack of claim 4, wherein at least another portion of the flexible package of the first and second cells lies flat against a support region of the serpentine separator.

6. The battery pack according to any one of claims 1 to 3, wherein the battery module further comprises:

and the middle layer is positioned between a supporting area of the zigzag partition plate and the first battery cell and the second battery cell.

7. The battery pack according to any one of claims 1 to 3,

the first battery cell and the second battery cell further comprise at least one electrode disposed on a first side of the first battery cell and the second battery cell,

the width of the channel of the meandering partition near the at least one electrode side is larger than the width of the channel of the meandering partition at the side far from the at least one electrode.

8. The battery pack according to any one of claims 1 to 3,

the thickness of the zigzag partition near the channel of the at least one electrode side is larger than the thickness of the zigzag partition at the channel far from the at least one electrode side.

9. The battery pack according to any one of claims 1 to 3, further comprising:

a fan for generating an air flow as the fluid; and

a housing for accommodating the fan and the battery module,

the fan is arranged on the side face of the battery module, so that the airflow passes through the plurality of channels, and the extending direction of the channels is approximately parallel to the advancing direction of the airflow.

10. The battery according to any one of claims 1 to 3, wherein the zigzag separator is a molded body.