KR20100131694A - Laptop-computer battery pack having a heat-pipe - Google Patents

Abstract

PURPOSE: A battery pack for a laptop computer in which a heat pipe circulates refrigerant is provided to prevent the excessive temperature rise of battery cells by distributing the heat to the outside without increasing the size of the battery pack. CONSTITUTION: Battery cells(300) are electrically connected. A BMU(Battery Management Unit)(250) is electrically connected to the battery cell and controls the charge and discharge of the battery cell. A packet case(110) receives the battery cells and the BMU. The pack case comprises a heat pipe(200) to the inside. The heat pipe includes a hollow in which refrigerant flows.

Description

Battery pack for notebook computer with heat pipe {LAPTOP-COMPUTER BATTERY PACK HAVING A HEAT-PIPE}

The present invention relates to a battery pack, and more particularly, to a battery pack for a notebook computer that is provided with a heat fight to improve the heat generation performance of the battery pack.

A notebook computer has the greatest advantage of being convenient to carry compared to a conventional desktop computer, and one of the biggest roles in enabling such a portable battery is a battery pack which is a power source of the notebook computer.

In general, a battery pack for a notebook computer has a structure in which a plurality of unit cells, such as a cylindrical secondary battery, are electrically connected and mounted in a pack case while a protective circuit element is mounted. As a pack case of a battery pack for a notebook computer, a polycarbonate material having excellent mechanical strength but low thermal conductivity is mainly used.

Therefore, when charging / discharging while the battery pack is mounted on the device, heat generated from the unit cells included in the battery pack is not discharged to the outside through the case, but is accumulated inside the battery pack and deteriorates the unit battery. Not only does it tend to result in the device being delivered to the device, but it also tends to degrade the device's performance.

On the other hand, the battery pack is a method for solving the safety problem when the temperature rises, a method for blocking the charge-discharge FET device or the fuse is used. In other words, the battery pack for the notebook computer is equipped with a temperature sensing element called a thermistor. When the temperature rises above the set value, the charge / discharge FET element is cut off and the fuse is blown at an extreme temperature rise. By doing so, the risk of ignition and explosion of the battery cell due to the abnormal temperature rise is prevented. However, if the fuse is blown, it means that the battery pack cannot be used again until the battery pack is repaired, so the user must bear the loss of having to purchase a new battery pack. Moreover, since the safety devices themselves do not provide a means for removing heat accumulated in the battery, the user is still exposed to the risk of fire and explosion of the battery.

Regarding the safety of a battery pack based on a secondary battery, Japanese Patent Application Laid-Open No. 1997-266016 discloses a medium and large battery pack by circulating a cooling liquid between a pack case and a plurality of cylindrical cells housed inside the pack case. A technique for cooling is disclosed. However, this technology has a high cooling efficiency because the liquid refrigerant and the unit cells are in direct contact with each other, which has relatively high cooling reliability, but there is a risk of corrosion and oxidation of the battery due to the direct contact between the liquid refrigerant and the unit cells. There is a problem that the likelihood of occurrence of an internal short circuit or explosion accordingly. In addition, the above technology may be applicable to medium and large battery packs of large devices such as electric vehicles and hybrid vehicles in terms of structure, but there are limitations in applying them to battery packs for notebook computers, which are relatively small.

In addition, Japanese Patent No. 3312852 discloses a technology for a medium-large battery pack in which a refrigerant flow path is formed in a pack case. That is, the patent discloses a technique for forming a predetermined flow path in the pack case and for cooling by flowing a refrigerant through the path. However, the above technique is also applicable to medium and large battery packs of large devices and difficult to apply to battery packs for notebook computers. In order to form the coolant flow path in the pack case, the thickness of the pack case must be at least a predetermined size, which causes a problem that the size of the pack case increases. In addition, due to the characteristics of the battery pack for the notebook computer, a lot of external force is applied during use, the formation of the refrigerant flow path can reduce the mechanical strength of the pack case may cause a safety problem rather.

Therefore, the development of a cooling technology that can be effectively applied to the battery pack for notebook computers is urgently required.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems of the prior art and the technical problems required from the past.

The inventors of the present application pay close attention to the above problems, and after repeated in-depth studies and experiments, a heat pipe is installed on one inner surface of the pack case, and a structure for circulating the refrigerant spontaneously along the heat pipe for the notebook computer. When manufacturing a battery pack, by utilizing the structural characteristics of the cylindrical battery cell, a unit cell constituting the battery pack to the maximum, without effectively causing the increase in the size of the battery pack, while effectively removing the heat generated during charging and discharging of the battery cell The advantages which can greatly improve the safety of have been confirmed, and the present invention has been completed.

The present invention has been made to solve the above problems of the prior art,

Two or more battery cells electrically connected and charged / discharged;

A BMU electrically connected to the battery cell to control charging and discharging of the battery cell;

A pack case accommodating the battery cell and the BMU therein

In the battery pack for a notebook computer comprising a,

The pack case provides a battery pack for a notebook computer, characterized in that provided with a heat pipe on its inner surface.

In addition, in the present invention, the heat pipe provides a battery pack for a notebook computer, characterized in that the diameter is within the range of 2 ~ 6 mm.

In the present invention, the heat pipe is provided with a hollow portion, the refrigerant flows in the hollow portion, provides a battery pack for a notebook computer, characterized in that the refrigerant is spontaneously vaporized, condensed and circulated through the hollow portion. .

In the present invention, the refrigerant is a battery pack for a notebook computer, characterized in that the one selected from water, freon gas, ammonia gas, acetone, methanol, ethanol.

In another aspect, the present invention provides a battery pack for a notebook computer, characterized in that the heat pipe is connected to the heat pipe, the outside of the pack case is further provided.

In addition, in the present invention, the heat dissipation member provides a battery pack for a notebook computer, characterized in that the heat radiation fin or a heat sink.

In addition, in the present invention, the heat pipe, provides a battery pack for a notebook computer, characterized in that located between the battery cell and the gap that the pack case is structurally made.

The battery pack for a notebook computer according to the present invention, by maximizing the structural characteristics of the battery cell as a unit cell, without causing an increase in the size of the battery pack, by circulating the refrigerant to disperse the heat accumulated inside the battery cell to the outside By preventing excessive rise in the temperature of the user, it is possible to protect the safety of the user from accidents caused by battery pack malfunction, and to prevent the life of the battery pack is shortened, it is possible to greatly improve the safety and reliability of the battery pack.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention,

Two or more battery cells electrically connected and charged / discharged;

A BMU electrically connected to the battery cell to control charging and discharging of the battery cell;

A pack case accommodating the battery cell and the BMU therein

In the battery pack for a notebook computer comprising a,

The pack case is characterized in that the inner surface with a heat pipe.

The battery pack according to the present invention is a battery pack for a notebook computer having a structure in which two or more battery cells form an electrical connection and a battery row (row) arranged in series or in parallel in a pack case, the battery cell is accommodated The inner surface of the pack case is provided with a heat pipe, through which the heat generated during the charging and discharging of the battery cell is configured.

The heat pipe is preferably in the range of 2 ~ 6 mm in diameter. In the range of less than 2 mm may not be enough to remove the heat of the battery cell, in the range of more than 6 mm there is a fear that there is insufficient space for accommodating the battery cell, the evaporation and condensation of the refrigerant may not occur spontaneously. .

That is, in the present invention, the heat pipe is provided with a hollow portion, the refrigerant flows in the hollow portion, and the refrigerant is spontaneously vaporized, condensed, and circulated through the hollow portion. In other words, in the present invention, the refrigerant is not forcedly circulated by the pump or the like, but circulated by the capillary phenomenon and the heat generated by the battery cell. The principle of heat transfer occurs through conduction of the heat pipe itself, but mainly through vaporization and condensation of the refrigerant.

The refrigerant may be used without limitation, conventional refrigerant used in the manufacture of a cooling device. Examples of such refrigerants include freon gas, ammonia, acetone, methanol, ethanol, and the like, and water may be used.

In some cases, a heat dissipation member adjacent to and connected to the heat pipe may be further installed in order to cool the refrigerant having risen in temperature while being circulated along the heat pipe. Such a heat dissipation member is preferably configured to have at least a portion thereof exposed to the outer surface of the pack case to emit heat to the outside of the pack case. In addition, the heat dissipation member may have a structure in which a heat dissipation fin or a heat dissipation plate is formed at a portion exposed to the outer surface of the pack case to increase the cross-sectional area in contact with the outside air to improve cooling efficiency.

The heat pipe is preferably formed in a space gap formed structurally between the battery cells and the pack case. For example, if the battery cell is a cylindrical cell, and the pack case has a flat surface of a square, Figure 4 (Figure 4 is a side cross-sectional view of one embodiment of the present invention between a circle and a straight line) There is no choice but to form a gap as shown in), and it is preferable that a heat pipe is formed to pass between these gaps.

By doing so, the overall size of the battery pack does not increase due to the heat pipe, and the contact capability with the battery cell is improved, and as a result, the heat dissipation efficiency of the battery cell can be increased without increasing the battery pack size.

The BMU is a control element used in a notebook computer battery pack, which will be apparent to those skilled in the art. The BMU performs functions such as a PCM (protective circuit module) of a small battery pack and a battery management system (BMS) of a large battery pack.

The position at which the BMU is mounted is not particularly limited, but as an example, the BMU may be installed at a position adjacent to the inner surface of the pack case, and may have a structure in which an external connection terminal of the BMU is exposed to the outside through the pack case. have.

The pack case constituting the battery pack of the present invention may have various forms. For example, the pack case may include an upper case and a lower case, and the upper case may be installed after installing a heat pipe, a pump, and a BMU to circulate refrigerant in the lower case. The cover may be sealed to seal the case.

Since a structure related to the battery pack for other notebook computers and a method of manufacturing the same are well known in the art, further description thereof will be omitted.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, this is for the easier understanding of the present invention, not intended to limit the scope of the invention to the embodiments.

1 is a perspective view of the inside of the refrigerant circulation battery pack according to an embodiment of the present invention.

Referring to FIG. 1, in one embodiment, the battery pack 100 includes six cylindrical battery cells 300 making electrical connections, and two battery strings in which three battery cells 300 are connected in series. It consists of the structure accommodated in 110. In addition, the inner surface of the pack case 110 is provided with a heat pipe 200 for circulating the refrigerant, one side of the pack case 110, the refrigerant is circulated along the heat pipe 200, the circulated refrigerant The heat dissipation fin 220 for dissipating heat is exposed to the outside from the inside of the pack case. The heat dissipation fin 220 is installed so that a portion thereof is exposed to the outer surface of the pack case 110, thereby dissipating heat to the outside of the pack case 110. In addition, a BMU 250 that controls charging and discharging of the battery cell 300 is provided on one inner surface of the pack case 110.

FIG. 2 is a schematic view showing a part of the battery pack of FIG. 1, and schematically illustrates a structure in which a refrigerant is circulated inside the battery pack.

Referring to FIG. 2, the refrigerant circulates through the heat pipe 200, and the circulation of the refrigerant circulates while spontaneously vaporizing and condensing through the hollow portion 210. This is a structure circulated by the heat generated by the capillary phenomenon and the battery cell. Since the refrigerant is spontaneously circulated by the generated heat, it also serves to alleviate the local temperature deviation of the battery cell by the refrigerant circulation.

3 is a schematic diagram of a refrigerant circulation type battery pack having battery cells, a heat pipe, a BMU, a heat dissipation member, and the like installed on a lower case and covering the upper case.

Referring to FIG. 3, although the inside of the battery pack 100 is sealed by the combination of the upper case 114 and the lower case 112, the refrigerant circulated through the heat pipes 200 of the battery pack 100. By circulating the inside, the heat generated during operation of the battery pack 100 is absorbed and released to the outside through the heat dissipation fin 220, so that a specific battery cell is excessively heated, or heat generated from the battery cells 100 ) To prevent accumulation inside.

Although described above with reference to the drawings according to an embodiment of the present invention, those of ordinary skill in the art will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

1 is a perspective view of the inside of a refrigerant circulation battery pack according to an embodiment of the present invention.

2 is a view schematically showing a structure in which a refrigerant is circulated inside the battery pack.

3 is a schematic diagram of a refrigerant circulation type battery pack completed by installing battery cells, a heat pipe, a BMU, a heat dissipation member, etc. in a lower case and covering the upper case;

Figure 4 is a side cross-sectional view of a battery pack according to an embodiment of the present invention.

Claims (7)

Two or more battery cells electrically connected and charged / discharged; A BMU electrically connected to the battery cell to control charging and discharging of the battery cell; A pack case accommodating the battery cell and the BMU therein In the battery pack for a notebook computer comprising a, The pack case is a battery pack for a notebook computer, characterized in that provided with a heat pipe on the inner surface. The battery pack of claim 1, wherein the heat pipe has a diameter within a range of 2 to 6 mm. The battery pack of claim 1, wherein the heat pipe has a hollow portion, a refrigerant flows in the hollow portion, and the refrigerant spontaneously vaporizes, condenses, and circulates through the hollow portion. The battery pack of claim 3, wherein the refrigerant is one selected from water, freon gas, ammonia gas, acetone, methanol, and ethanol. The battery pack of claim 1, further comprising a heat dissipation member connected to the heat pipe and exposed to the outside of the pack case. The battery pack of claim 5, wherein the heat dissipation member is a heat dissipation fin or a heat dissipation plate. The battery pack of claim 1, wherein the heat pipe is located between the battery cell and a gap that the pack case is structurally formed.

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