JP2008181822A - Battery pack, and its manufacturing method - Google Patents

Battery pack, and its manufacturing method Download PDF

Info

Publication number
JP2008181822A
JP2008181822A JP2007015667A JP2007015667A JP2008181822A JP 2008181822 A JP2008181822 A JP 2008181822A JP 2007015667 A JP2007015667 A JP 2007015667A JP 2007015667 A JP2007015667 A JP 2007015667A JP 2008181822 A JP2008181822 A JP 2008181822A
Authority
JP
Japan
Prior art keywords
heat
battery
battery cells
battery pack
electrode terminals
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2007015667A
Other languages
Japanese (ja)
Inventor
Wataru Okada
渉 岡田
Original Assignee
Sanyo Electric Co Ltd
三洋電機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sanyo Electric Co Ltd, 三洋電機株式会社 filed Critical Sanyo Electric Co Ltd
Priority to JP2007015667A priority Critical patent/JP2008181822A/en
Publication of JP2008181822A publication Critical patent/JP2008181822A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • Y02E60/12

Abstract

<P>PROBLEM TO BE SOLVED: To effectively inhibit high temperature heat conduction via an electrode terminal. <P>SOLUTION: This is a battery pack in which a plurality of battery cells are adjoined and connected in series and/or in parallel with each other, and is equipped with the plurality of the battery cells in which positive and negative electrode terminals 12 are projected from one end face, and the plurality of separators which connect the electrode terminals 12 to each other and which insulate and heat-insulate the battery cells by being respectively interposed between conductive heat-sensitive shutoff members 80 for releasing a connection state according to heat. The heat-sensitive shutoff members 80 are constituted so as to be fused when heated to a temperature equal to or higher than a predetermined temperature, and so as to release a physical connection between the electrode terminals 12. By this, even if a part of the battery cells abnormally generates heat, the heat is insulated by the separators between the mutually adjoining battery cells, and even as for the heat to be conducted through the electrode terminals 12, the heat-sensitive shutoff members 80 are fused by the heat to divide a heat conductive passage, and a situation can be inhibited in which abnormal heating spreads catenately. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a battery pack in which a plurality of battery cells are connected in series and / or in parallel, and a method for manufacturing the same.

Battery packs (packed batteries) or battery packs used as power sources for electric vehicles and hybrid vehicles are required to have high output in a limited space. Square batteries with higher energy density than cylindrical batteries are required. Sometimes used. On the other hand, in a battery pack in which a plurality of such prismatic batteries are connected in series and / or in parallel, the adjacent prismatic battery cells are in close contact with each other, so that efficient heat dissipation is required. In particular, in a lithium ion battery, some battery cells may become hot for some reason. When some of the battery cells generate heat, the heat propagates to surrounding batteries, and high-temperature battery cells increase one after another, which may cause thermal runaway. For this reason, the structure which insulates adjacent battery cells effectively and prevents thermal runaway is calculated | required. For example, the structure which interposes the separator which has heat insulation and insulation between adjacent battery cells is used (for example, patent document 1, 2).
JP 2006-48996 A JP 2004-362879 A

  However, the separator can insulate the outer can of the battery cell, but cannot prevent heat conduction through the electrode terminal. Since battery cells electrically connect a plurality of battery cells in series and / or in parallel, it is necessary to connect electrode terminals in a conductive state. Since the electrode terminal is composed of a metal having excellent conductivity, it has excellent heat conduction, and heat conduction at this portion cannot be prevented, and heat conduction through the electrode terminal occurs during abnormal heat generation. there were.

  The present invention has been made to solve such problems. A main object of the present invention is to provide a battery pack capable of effectively preventing high-temperature heat conduction through an electrode terminal and a manufacturing method thereof.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, a battery pack of the present invention is a battery pack in which a plurality of battery cells are adjacent and connected in series and / or in parallel, with positive and negative electrode terminals protruding from one end face. In addition to electrically connecting the plurality of battery cells and the electrode terminals, the conductive heat-sensitive blocking member that releases the connection state in response to heat is interposed between the adjacent battery cells, and between the battery cells. A plurality of separators that insulate and insulate, and the thermal barrier member melts when the battery cell of the electrode terminal to which the thermal barrier member is connected is heated to a predetermined temperature or higher due to a temperature rise, and physically between the electrode terminals Configured to disconnect. As a result, even if some of the battery cells generate abnormal heat, the separator is insulated from the adjacent battery cells, and the heat-sensitive blocking member is also melted by heat with respect to the heat conducted through the electrode terminals. As a result, it is possible to prevent a situation where the heat conduction path is divided and abnormal heat generation is chained.

  Preferably, the electrode terminal is formed in a plate shape, the plate electrode terminal protrudes upward from the end surface of the battery cell, has a bent curved surface by bending the tip, and the folded curved surface is formed on an adjacent battery cell. When the battery cells are stacked so as to protrude toward each other, the edges of the folding surfaces of the adjacent battery cells are opposed to each other, and the heat-sensitive blocking member can be arranged between the edges. Thereby, the heat-sensitive interruption | blocking member which is located between edge and makes an electrical connection fuse | melts by the heat_generation | fever of a battery cell, can block | interrupt between edge surfaces spatially and can prevent heat conduction effectively. .

  The battery cell can also be provided with a guide for guiding the heat-sensitive blocking member when it is melted by heat. Thereby, the heat-sensitive blocking member melted by the heat generation of the battery cell can be guided by the guide, and the melted heat-sensitive blocking member can be prevented from falling and scattering to cause an unintended short circuit.

  On the other hand, the heat blocking member preferably has a melting temperature of 200 ° C to 300 ° C. As a result, the melting temperature is set to a temperature at which the battery cell may cause thermal runaway or lower, and the heat conduction of the electrode terminal is performed before the abnormally heated battery cell adversely affects the surrounding battery cells. The path can be blocked and the thermal chain can be effectively blocked.

  As the heat-sensitive blocking member, silver-containing solder is preferably used. Thus, the heat conduction path of the electrode terminal can be blocked before the abnormally heated battery cell adversely affects the surrounding battery cells, thereby effectively preventing the thermal chain.

  On the other hand, the other battery pack is a battery pack in which a plurality of battery cells are adjacent to each other and connected in series and / or in parallel to each other, and positive and negative electrode terminals protrude from one end surface and adjacent battery cells are connected to each other. A plurality of battery cells that are electrically connected to each other by electrode terminals, a physical thermal connection between the electrode terminals, a conductive heat-sensitive cutoff member that releases the connection state according to heat, and between adjacent battery cells A bimetallic structure comprising a plurality of separators interposed between each of the battery cells to insulate and insulate between the battery cells, wherein the heat-sensitive blocking member is joined to at least one of the electrode terminals with a dissimilar metal different from the metal constituting the electrode terminal. When the temperature of the battery cell to which the electrode terminal is connected is heated to a predetermined temperature or higher, the bimetal structure is deformed and the physical connection between the electrode terminals is released. As a result, when some of the battery cells generate abnormal heat, the heat is detected and the bimetal connected to the battery cells is deformed to break the physical connection between the electrode terminals, thereby blocking the heat transfer between the electrode terminals. It is possible to prevent a situation where abnormal heat generation is chained.

  Still another battery pack is a battery pack in which a plurality of battery cells are adjacent to each other and connected in series and / or in parallel to each other, and a plurality of battery cells in which positive and negative electrode terminals protrude from one end surface, and electrode terminals A conductive heat-sensitive blocking member that electrically connects each other and releases the connection state in response to heat, a bi-metal bonded to a different metal and connected to the heat-sensitive blocking member and the heat-conductive state, and adjacent battery cells A plurality of separators that are respectively interposed between the battery cells to insulate and insulate between the battery cells, a detection unit that detects that the bimetal is heated to a predetermined temperature or more due to a rise in the temperature of the battery cells, and a deformation of the bimetal by the detection unit. When detected, the battery cell and the electrode terminal can be provided with cooling means for forcibly cooling. Thereby, when some of the battery cells abnormally generate heat, the heat is sensed by the bimetal and the cooling means performs forced cooling, so that the chain of thermal runaway can be effectively prevented.

  This detection means may comprise a strain gauge. Thereby, the change of the bimetal can be detected by the strain gauge, and the cooling means can be controlled based on the resistance change.

  The detecting means may be a switch that is turned ON / OFF by deformation of the bimetal. Thereby, the cooling means can be reliably controlled by mechanically turning the switch ON / OFF by deformation of the bimetal.

  The battery pack manufacturing method is a battery pack manufacturing method in which a plurality of battery cells are adjacent to each other and connected in series and / or in parallel to each other, and includes a plate-like electrode terminal protruding upward from an end surface. Preparing the electrode terminal, bending the electrode terminal toward the adjacent battery cell in a substantially L-shaped cross-section, and separating the electrode terminal between the adjacent battery cells in a state of facing each other, A step of filling a heat-sensitive blocking member that melts when heated to a predetermined temperature or more between the end faces of the electrode terminals. As a result, even if some of the battery cells generate abnormal heat, the separator is insulated from the adjacent battery cells, and the heat-sensitive blocking member is also melted by heat with respect to the heat conducted through the electrode terminals. As a result, it is possible to prevent a situation where the heat conduction path is divided and abnormal heat generation is chained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a battery pack and its manufacturing method for embodying the technical idea of the present invention, and the present invention specifies the battery pack and its manufacturing method as follows. do not do. Moreover, the member shown by the claim is not what specifies the member of embodiment. In addition, the size, positional relationship, and the like of members illustrated in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and reference numeral indicate the same or the same members, and detailed description will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.
(Embodiment 1)

FIG. 1 is an external perspective view of battery pack 100 according to Embodiment 1 of the present invention, FIG. 2 is a perspective view of battery cell stack 1 constituting battery pack 100, and FIG. 4 is a plan view of the battery cell laminate 1, FIG. 5 is a side view of the battery cell laminate 1, and FIG. 6 is a perspective view of the heat-sensitive blocking member 80 in a molten state. The battery pack 100 shown in these drawings is an in-vehicle battery pack, in which a plurality of battery cells 10 and separators 20 are alternately stacked, and left and right end surfaces are covered with an end plate 30. Specifically, the rectangular battery cells 10 are sandwiched between frame-shaped separators 20 and stacked in multiple stages with the upper and side surfaces of the battery cells 10 exposed. In this example, nine battery cells 10 are stacked on the main surface.
(Battery cell 10)

  As the battery cell 10, a substantially rectangular prismatic battery covered with a prismatic outer can is used. Square battery cells can be arranged more efficiently than cylindrical batteries, and can increase the energy density per unit volume. Especially for in-vehicle applications, there is a high demand for space saving, which is preferable. For such a battery cell, a rectangular secondary battery such as a lithium ion secondary battery can be used. Moreover, it is good also as a primary battery other than a nickel battery. The electrode terminals 12 of the battery cells 10 are connected in series or in parallel. Furthermore, it is connected to a control circuit (not shown) at the end of the battery pack 100, and the voltage, current, temperature, etc. of each battery cell 10 is measured by the control circuit, and the battery capacity and required charge / discharge amount are determined. Control such as charging and discharging is performed.

As shown in the perspective view of FIG. 2, the battery cell 10 has positive and negative electrode terminals 12 protruding from the upper surface of a rectangular outer can whose sides are chamfered. The position where the electrode terminal 12 protrudes is set to a position where the positive electrode and the negative electrode are symmetrical on the main surface of the outer can. Thereby, when the battery cell 10 is turned over and overlapped, the positive electrode and the negative electrode can be overlapped, and series connection can be easily performed. Each of the electrode terminals 12 is bent into an L-shaped cross section. At this time, as shown in FIG. 5, the positive and negative electrode terminals 12 are bent in opposite directions, and the end face of the bent piece (folded curved surface 12d) of the electrode terminal 12 between the adjacent battery cells 10 is It is designed so that the end faces are separated from each other by a predetermined distance with the battery cells stacked. Between the electrode end faces, a heat-sensitive blocking member 80 is filled and electrically connected. As shown in FIG. 2, the battery cell 10 is formed with terminal ribs 14 standing upright so as to surround the periphery of the electrode terminal 12, whereby the electrolyte in the outer can is leaked from the periphery of the electrode terminal 12. Even so, the situation of inadvertent spreading is prevented.
(Separator 20)

As shown in FIGS. 1 and 2, the battery cell 10 is coated on the outside so as to be sandwiched by separators 20 from both sides. The separator 20 is configured in a frame shape having a size covering the battery cell 10, and exposes both side surfaces and upper and lower end surfaces of the battery cell 10 in a state of covering the battery cell 10, and covers the four corners. Further, the adjacent separators 20 are stacked with the corners in contact with each other. The separator 20 is composed of a member having excellent heat resistance and heat insulation, and is preferably formed of a lightweight and inexpensive resin. For example, a synthetic resin such as polypropylene or polyurethane having a low thermal conductivity (preferably 0.5 W / m or less) can be used. Thereby, while protecting the battery cell 10 with the separator 20, the adjacent battery cells 10 are insulated and insulated. In addition, a slit having a concave-convex cross section is formed on the bottom surface of the separator 20, and the battery cell 10 is cooled from the side surface by passing a cooling medium from a cooling means 87 described later using the slit as a path.
(End plate 30)

In the state where the separators 20 and the battery cells 10 are alternately connected to each other as described above, the end surfaces are covered with the end plate 30 and fixed. The end plate 30 is formed in a size that can cover the battery cell 10 exposed at the end face, and is fixed to be sandwiched from both sides. In this example, a pair of screw holes 32 are protruded from the side surface of the end plate 30, and the end plates 30 are fixed by screwing through extension bolts 34 extended to the side surface of the battery pack 100 on which the battery cells 10 are stacked. The end plate 30 is preferably made of metal or resin, which can be molded by integral molding.
(Thermal shutdown member 80)

  As shown in FIGS. 2 to 5, the electrode terminal 12 is formed by bending the positive electrode and the negative electrode in an L-shaped cross section in opposite directions, and by stacking adjacent battery cells in the same posture, The electrode terminals 12 can be connected in series by being electrically connected through the heat-sensitive blocking member 80. As shown in FIG. 2, the heat-sensitive blocking member 80 is filled between the edges of the folding surface 12d and bonded and fixed to electrically connect the electrode terminals 12 to each other. The heat-sensitive blocking member 80 is made of a conductive material and melts when the temperature reaches a predetermined temperature. That is, when the temperature of the battery cell rises, the heat-sensitive blocking member 80 is heated via the electrode terminal 12. And if it heats more than predetermined temperature, the heat-sensitive interruption | blocking member 80 will melt | dissolve, and as shown in FIG. Heat conduction through the electrode terminal 12 is blocked. In particular, the air layer has a high heat insulating effect. At the same time, since the electrical connection is also released, charging / discharging of the battery cells that generate heat is forcibly stopped, and it is expected to work in a direction that suppresses heat generation. As described above, in the conventional heat insulating structure using the separator, although heat conduction through the outer can of the battery cell can be prevented, there is a problem that heat conduction through the electrode terminal cannot be prevented. By making it fusible, the heat conduction path can be completely blocked to ensure reliable insulation, and thermal runaway can be effectively prevented.

  The heat-sensitive blocking member 80 is preferably set so as to reach the temperature of the electrode terminal 12 when the temperature rises to a temperature at which there is a risk of thermal runaway of the battery cell, or the melting start temperature at which melting starts before that. Therefore, the heat-sensitive blocking member 80 is preferably made of a low melting point metal or alloy, specifically, a metal that melts at about 200 ° C. to 300 ° C. For example, a lead-tin-based solder containing silver and having excellent electrical conductivity can be used. In this embodiment, a lead-free low-temperature solder containing Sn 1%, Ag 4.1%, Cu 0.5%, and In 4.0% was used. In addition, in this specification, the term “melting” includes a state in which the heat-sensitive blocking member melts and changes to a liquid state, and also vaporizes. Examples of such a heat-sensitive barrier member include sublimable metal compounds such as palladium, platinum, and copper acetylacetonate complexes that have sublimability at high temperatures. Moreover, a thermal fuse can also be used as a heat-sensitive interruption member.

  The heat-sensitive blocking member 80 is fixed between the end faces in a molten state. For example, when solder is used, a receiving plate is disposed below the end surfaces, filled with molten solder, cooled and solidified, and then the receiving plate is removed. Further, as shown in FIG. 8 to be described later, the distance D between the end faces can be fixed when the heat-sensitive blocking member 80 is fixed and easily flows out when the heat-sensitive blocking member 80 is melted. Is set to a size large enough to insulate. For example, if the distance D between the end faces is too narrow, the heat insulation effect by the air layer cannot be sufficiently exerted and the heat insulation effect becomes insufficient, or even if the heat-sensitive blocking member 80 is melted, the surface tension does not fall between the end faces. It is possible that it will remain. On the other hand, if the distance D is too long, the amount of the heat-sensitive blocking member 80 used is increased, filling becomes difficult, the resistance value due to the solder is increased, the heat capacity is further increased, and there is a possibility that a time delay occurs in melting. For this reason, the distance between the end faces depends on the type of heat-sensitive blocking member used, the viscosity at the time of melting, the area of the end face, the melting start temperature and the thermal conductivity of air at that temperature, the material of the electrode terminal and the melting start temperature. It is set appropriately according to the coefficient of thermal expansion. Considering these, the distance D between the end faces is preferably set to 2 mm to 3 mm.

  Cross-sectional views of the space between the end faces of the folded curved surface 12d where the heat-sensitive blocking member 80 is disposed are shown in FIGS. In the space between the end surfaces, the end surface 15 of the folding surface 12d is a concave curved surface as shown in FIG. 7 so that the heat-sensitive blocking member 80 can be easily held. Thereby, it is possible to easily fix the heat-sensitive blocking member 80 between the end surfaces in a molten state. On the other hand, in order to facilitate melting and outflow when heated to a predetermined temperature, the end surface 15B of the folding surface 12d 'is made flat in the example of FIG. The closer the end surface 15B is to the vertical surface, the easier it is to drop the melted heat-sensitive blocking member 80. Further, in the example of FIG. 9, the end surface 15C of the fold surface 12d ″ is formed so that the cross section between the end surfaces has an inverted C shape. In this way, the end surface 15C is inclined to thereby melt the heat-sensitive blocking member. 80 can be collected in one point so that outflow and recovery can be performed smoothly.

  The heat-sensitive blocking member 80 that has flowed out falls to the end surface of the upper surface of the battery cell. At this time, it is preferable to provide a guide for guiding and accumulating the molten heat-sensitive blocking member 80 on the end face of the battery cell so that the conductive heat-sensitive blocking member 80 is not scattered to cause an unintended short circuit. For example, as shown in FIG. 10, a part of the end face of the battery cell is covered with a separator, and a guide region GZ defined by upright walls 16 is formed so as to surround a position almost directly below the terminals. The upright wall 16 can be molded integrally with the separator. Alternatively, a part of the upright wall may be opened to form a bowl shape so that the molten heat-sensitive blocking member 80 flows out of the battery pack.

With this configuration, when some of the battery cells abnormally generate heat, the heat conduction path to other battery cells can be reliably cut off to prevent thermal chain or thermal runaway. For example, when the battery cell B abnormally generates heat in the example of FIG. 2, as shown in FIG. 6, the heat-sensitive blocking members 80A and 80B are melted between the two end faces, and the heat generation of the battery cell 10B is caused by the adjacent battery cell. Conduction to 10A and 10C can be suppressed, and thermal runaway can be avoided.
(Embodiment 2)

  In the above, the structure which interrupts | blocks a heat conduction path | route by making a heat-sensitive interruption | blocking member lose | disappear according to a heat | fever was demonstrated. On the other hand, the heat conduction path can be similarly blocked by deforming the heat-sensitive blocking member according to heat. Next, a battery pack according to Embodiment 2 will be described with reference to FIGS. In these drawings, FIG. 11 is a perspective view showing a state in which the electrode terminals 12 of the battery cell laminate 2 of the battery pack are in a connected state, FIG. 12 is a side view thereof, FIG. 13 is a plan view, and FIG. 15 is an enlarged view showing the electrode terminal 12 and the heat-sensitive blocking member 80B, FIG. 16 is a perspective view showing one electrode terminal 12 in a separated state, FIG. 17 is a side view thereof, FIG. 18 is a plan view, FIG. 19 is a front view, and FIG. 20 is an enlarged view of the electrode terminal 12 and the heat-sensitive blocking member 80, respectively. In the battery pack shown in these drawings, a bent curved surface 12e in which the shape of the electrode terminal 12 is bent in a substantially L shape is overlapped between adjacent battery cells and electrically connected. Specifically, positive and negative plate-like electrode terminals 12 are projected from the upper surface of the outer can, and the positive electrode and the negative electrode are protruded from the left and right symmetrical positions on the main surface of the outer can, and each electrode terminal 12 is L-shaped in cross section. It is bent. Further, the bending direction is bent in opposite directions at the positive and negative electrode terminals 12 and protrudes from the side surface of the battery cell, and the bent surface 12e, which is a bent piece, is formed between the adjacent battery cells 10. The folding surface 12e is extended to a length that allows the folding surfaces 12e to overlap each other. In addition, the bending position of the electrode terminal 12 is offset by an amount corresponding to the thickness of the electrode terminal 12 between the positive electrode and the negative electrode. Accordingly, when the battery cells 10 are stacked as shown in FIG. 11, the folding surfaces 12e of the adjacent battery cells 10 can be overlapped while the end surfaces of the battery cells 10 are maintained on substantially the same plane. The folded surface 12e is fixed by spot welding or the like.

  One of the electrode terminals 12 has a bimetal structure in which different metals are joined. Specifically, as shown in the enlarged view of FIG. 15, the electrode terminal 12 has a two-layer structure in which metals having different thermal expansion coefficients are further laminated on the upper surface side of the original electrode terminal 12. When the temperature of the electrode terminal 12 increases due to the difference in thermal expansion coefficient, the bending angle of the bending surface 12e changes and the connected state is released. In the example of FIGS. 15 and 20, the electrode terminal 12 located above the folding surface 12e has a bimetallic structure, and the thermal expansion coefficient of the dissimilar metal fixed to the upper side of the electrode terminal 12 is set to the lower electrode terminal 12 as shown in FIG. By making it lower than the metal constituting, the bent surface 12e is bent and separated so as to jump upward as shown in FIG. 20 due to the temperature rise, and the connected state is released. In this example, a lithium ion battery is used for the battery cell, and the upper electrode terminal 12 is a negative electrode terminal made of Cu. In this case, an Fe—Ni alloy can be used as the dissimilar metal. Moreover, the positive electrode terminal comprised with Al can also be made into a bimetal structure. Furthermore, the same effect can be obtained by making the folded curved surface superimposed on the lower side opposite to the above to have a bimetal structure and bend downward. The configuration in which the upper folding surface is flipped upward is preferable in that when there is no obstacle above the battery pack, the electrode terminals can be reliably separated. On the other hand, the configuration in which the lower folding surface is bent downward is preferable in that an extra space is not required. In any case, the shortest distance d between the electrode terminals in the separated state is separated by 1 mm or more so that it can be spatially separated to exhibit a sufficient heat insulating effect by the air layer. As described above, when some of the battery cells generate abnormal heat, the heat is transferred to the electrode terminals, and one electrode terminal is deformed due to the difference in coefficient of thermal expansion. Can be blocked.

The fixed strength of the folding surface 12e is set so that the connection between the folding surfaces 12e can be released by the deformation stress of the bimetal structure. In this example, the bent curved surfaces 12e are partially fixed by spot welding, and the connection state is broken and separated by the deformation of the bimetal. Although the above bimetal structure is a two-layer structure, it goes without saying that three or more layers can be adopted.
(Embodiment 3)

  In the above configuration, the heat generation of the battery cell is detected by the heat-sensitive blocking member, and the propagation of abnormal heat generation is blocked by blocking the heat conduction path. However, it may be configured to actively cool by detecting heat generation. A battery pack according to Embodiment 3 will be described with reference to FIGS. In these drawings, FIG. 21 is a block diagram of a battery pack that realizes a thermal shut-off mechanism, FIG. 22 is a perspective view of the battery cell laminate 3 constituting the battery pack, FIG. 23 is a side view thereof, and FIG. FIG. 25 shows front views, respectively. In the battery pack shown in these figures, the battery cell bends the electrode terminal 12 in the L-shaped cross section in the opposite direction to the positive electrode and the negative electrode, as in the second embodiment, and the position where the battery cell is bent. The positive electrode and the negative electrode are offset by an amount corresponding to the thickness of the electrode terminal 12. Thereby, when the battery cells 10 are stacked as shown in FIG. 22, the folding surfaces 12 a of the adjacent battery cells 10 can be overlapped while the end surfaces of the battery cells 10 are maintained substantially on the same plane.

  The electrode terminals 12 superposed in this way are fixed using a fixing tool FS. When the folding surfaces 12a of the adjacent battery cells 10 are overlapped, the connecting holes 13 opened in the respective folding surfaces 12a are at least partially matched, and an insertion body for the fixture FS is inserted therein. At this time, by increasing the inner diameter of the connecting hole 13 of the upper folded curved surface 12a among the folded curved surfaces 12a to be superimposed, the dimensional tolerance can be absorbed and alignment can be facilitated. Bolts and nuts can be used as fixtures. Rivets and blind rivets can also be used as fixtures. Here, a bolt is inserted into the connecting hole 13 as an insertion body, and is screwed with a nut below the connecting hole 13 to fix the folded curved surfaces 12a. At this time, the bimetal 82 is also fixed to the folding surface 12a.

  The bimetal 82 forms an opening similar to the connection hole 13 and is fastened together with the folding surface 12a with a bolt. In this state, the bimetal 82 is connected to the folding surface 12a in a heat conducting state. Further, a strain gauge 84 is fixed to the bimetal 82 as detection means for detecting deformation of the bimetal 82. As the strain gauge 84, a resistance wire strain gauge using a resistance change of a metal resistor can be used, and the minute extension and contraction of the bimetal 82 is measured. In the example of FIG. 22, the bimetal 82 is fixed to the two folding surfaces 12a on one side of the battery pack, and the output of the strain gauge 84 fixed to the bimetal 82 is as shown in the block diagram of FIG. Are input to the detection circuit 85. The detection circuit 85 detects a resistance change detected by the strain gauge 84 using a bridge circuit, a current amplifier, or the like. Further, the detection circuit 85 is connected to the control means 86. The control means 86 monitors the temperature change of the bimetal 82, that is, the temperature change of the battery cell based on the detection signal detected by the detection circuit 85, and the cooling means 87 according to the temperature. To control the operation. The cooling unit 87 cools the battery cell by circulating a cooling medium through a cooling path for cooling the battery cell. The cooling means 87 is comprised by the ventilation fan which flows air as a cooling medium to the uneven | corrugated shaped slit provided in the separator mentioned above, for example. The bimetal 82 may be used as a thermostat so that the switch of the cooling means 87 is directly turned on / off.

  As described above, when the abnormal temperature of the battery cell is detected, the thermal runaway chain can be suppressed by forcibly operating the cooling means 87 and cooling the electrode terminal and the battery cell surface. In general, it is difficult and costly to directly fix the temperature sensors to the electrode terminals. However, with the above configuration, the cooling means 87 can be controlled relatively inexpensively using a bimetal.

  The battery pack and the manufacturing method thereof according to the present invention can be suitably applied as a power supply device for a vehicle such as an electric vehicle or a hybrid vehicle.

It is an external appearance perspective view which shows the battery pack which concerns on Embodiment 1 of this invention. It is a perspective view of the battery cell which comprises the battery pack of FIG. It is a front view of the battery cell laminated body of FIG. It is a top view of the battery cell laminated body of FIG. It is a side view of the battery cell laminated body of FIG. It is a perspective view which shows the state which the heat-sensitive interruption | blocking member fuse | melted from the state of FIG. It is sectional drawing which shows the shape of the end surface which made the end surface of a folding surface oppose. It is sectional drawing which shows the other shape of the end surface which made the end surface of a folding surface oppose. It is sectional drawing which shows the other shape of the end surface which made the end surface of a folding surface oppose. It is a perspective view which shows the battery pack which concerns on a modification. It is a perspective view which shows a mode that each electrode terminal of the battery cell laminated body of a battery pack exists in a connection state. It is a side view of the battery cell laminated body of FIG. It is a top view of the battery cell laminated body of FIG. It is a front view of the battery cell laminated body of FIG. It is an enlarged view which shows the electrode terminal and heat-sensitive interruption | blocking member of FIG. It is a perspective view which shows a mode that one electrode terminal exists in a isolation | separation state. It is a side view of the battery cell laminated body of FIG. It is a top view of the battery cell laminated body of FIG. It is a front view of the battery cell laminated body of FIG. It is an enlarged view of the electrode terminal of FIG. 16, and a heat-sensitive interruption | blocking member. It is a block diagram of the battery pack which implement | achieves a thermal shut-off mechanism. It is a perspective view of the battery cell aggregate | assembly which comprises the battery pack of FIG. It is a side view of the battery cell laminated body of FIG. It is a top view of the battery cell laminated body of FIG. It is a front view of the battery cell laminated body of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Battery pack 1-3 ... Battery cell laminated body 10, 10A, 10B, 10C ... Battery cell 12 ... Electrode terminal 12a, 12d, 12d ', 12d ", 12e ... Folding curved surface 13 ... Connection hole 14 ... Terminal rib 15, 15B, 15C ... End face 16 ... Upright wall 20 ... Separator 30 ... End plate 32 ... Screw hole 34 ... Extension bolt 80, 80A, 80B ... Thermal shut-off member 82 ... Bimetal 84 ... Strain gauge 85 ... Detection circuit 86 ... Control means 87 ... Cooling means FS ... Fixing tool GZ ... Guide area

Claims (10)

  1. A battery pack in which a plurality of battery cells are adjacent and connected in series and / or in parallel to each other,
    A plurality of battery cells in which positive and negative electrode terminals protrude from one end surface;
    Electrically connecting the electrode terminals to each other, and a conductive heat-sensitive blocking member that releases the connection state according to heat,
    A plurality of separators that are respectively interposed between adjacent battery cells to insulate and insulate between the battery cells;
    With
    The heat-sensitive blocking member is configured to melt when the temperature of the battery cell of the electrode terminal to which the heat-sensitive blocking member is connected is heated to a predetermined temperature or higher to release the physical connection between the electrode terminals. A battery pack characterized by
  2. The battery pack according to claim 1,
    The electrode terminal is formed in a plate shape, the plate electrode terminal protrudes upward from the end surface of the battery cell, has a bent curved surface by bending the tip,
    When the folded curved surfaces protrude toward the adjacent battery cells and the battery cells are stacked, the edges of the folded curved surfaces of the adjacent battery cells are opposed to each other, and the thermal shutdown is between the edges. A battery pack comprising a member.
  3. The battery pack according to claim 2,
    The battery cell includes a guide that guides the heat-sensitive blocking member when the heat-sensitive blocking member is melted by heat.
  4. The battery pack according to any one of claims 1 to 3,
    The battery pack, wherein a temperature at which the heat-sensitive blocking member melts is 200 ° C to 300 ° C.
  5. The battery pack according to any one of claims 1 to 4,
    The battery pack, wherein the heat-sensitive blocking member is a solder containing silver.
  6. A battery pack in which a plurality of battery cells are adjacent and connected in series and / or in parallel to each other,
    A plurality of battery cells in which positive and negative electrode terminals protrude from one end face, and adjacent battery cells are electrically connected to each other by electrode terminals, and
    Conductive thermal shut-off member that releases the physical connection between the electrode terminals in response to heat,
    A plurality of separators that are respectively interposed between adjacent battery cells to insulate and insulate between the battery cells;
    With
    The heat-sensitive blocking member has a bimetallic structure in which a dissimilar metal different from the metal constituting the electrode terminal is bonded to at least one of the electrode terminals, and a predetermined temperature is reached due to a temperature increase of a battery cell to which the electrode terminal is connected. The battery pack is configured so that the bimetal structure is deformed when heated to the above and the physical connection between the electrode terminals is released.
  7. A battery pack in which a plurality of battery cells are adjacent and connected in series and / or in parallel to each other,
    A plurality of battery cells in which positive and negative electrode terminals protrude from one end surface;
    Electrically connecting the electrode terminals to each other, and a conductive heat-sensitive blocking member that releases a connection state in response to heat; and a bimetal that is connected to the heat-sensitive blocking member and is in a heat-conducting state and joined with dissimilar metals;
    A plurality of separators that are respectively interposed between adjacent battery cells to insulate and insulate between the battery cells;
    Detecting means for detecting that the bimetal is heated to a predetermined temperature or higher due to a temperature rise of the battery cell;
    A cooling means for forcibly cooling the battery cell and the electrode terminal when bi-metal deformation is detected by the detection means;
    A battery pack comprising:
  8. The battery pack according to claim 7,
    The battery pack, wherein the detection means includes a strain gauge.
  9. The battery pack according to claim 7,
    The battery pack, wherein the detecting means is a switch that is turned on / off by deformation of the bimetal.
  10. A method of manufacturing a battery pack in which a plurality of battery cells are adjacent and connected in series and / or in parallel to each other,
    Preparing a battery cell having a plate-like electrode terminal protruding upward from an end surface;
    Bending the electrode terminal toward the adjacent battery cell in a substantially L-shaped cross-section, and separating the electrode terminal between the adjacent battery cells in a state of facing each other;
    Filling a heat-sensitive blocking member that melts when heated above a predetermined temperature between the end faces of the electrode terminals;
    The manufacturing method of the battery pack characterized by including.
JP2007015667A 2007-01-25 2007-01-25 Battery pack, and its manufacturing method Pending JP2008181822A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2007015667A JP2008181822A (en) 2007-01-25 2007-01-25 Battery pack, and its manufacturing method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2007015667A JP2008181822A (en) 2007-01-25 2007-01-25 Battery pack, and its manufacturing method

Publications (1)

Publication Number Publication Date
JP2008181822A true JP2008181822A (en) 2008-08-07

Family

ID=39725543

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2007015667A Pending JP2008181822A (en) 2007-01-25 2007-01-25 Battery pack, and its manufacturing method

Country Status (1)

Country Link
JP (1) JP2008181822A (en)

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009211998A (en) * 2008-03-05 2009-09-17 Nissan Motor Co Ltd Cooling device for battery pack
JP2010049842A (en) * 2008-08-19 2010-03-04 Sanyo Electric Co Ltd Battery pack for vehicle
WO2010082254A1 (en) * 2009-01-16 2010-07-22 トヨタ自動車株式会社 Electrical storage device
WO2011007547A1 (en) * 2009-07-17 2011-01-20 パナソニック株式会社 Battery module and battery pack using same
JP2011034775A (en) * 2009-07-31 2011-02-17 Sanyo Electric Co Ltd Assembled battery cooling structure and battery system
JP2011508391A (en) * 2007-12-25 2011-03-10 ビーワイディー カンパニー リミテッド Protective cover for battery cell end cap assembly
JP2011510433A (en) * 2007-12-25 2011-03-31 ビーワイディー カンパニー リミテッド Battery system for a vehicle having a separable connection
JP2011096536A (en) * 2009-10-30 2011-05-12 Sanyo Electric Co Ltd Power supply device and vehicle with the same
US8007935B2 (en) 2006-10-30 2011-08-30 Byd Co., Ltd. Plate assembly, core and lithium ion battery
US8092936B2 (en) 2007-12-25 2012-01-10 Byd Co. Ltd. Electrochemical cell having a coiled core
US8178230B2 (en) 2007-12-18 2012-05-15 Byd Co., Ltd. Battery pack
US8178225B2 (en) 2007-11-29 2012-05-15 Byd Co., Ltd. Battery and preparation method thereof
JP2012512504A (en) * 2008-12-16 2012-05-31 インパクト クリーン パワー テクノロジー スポルカ アキジナ Thermal stabilization electric battery module
JP2012164463A (en) * 2011-02-04 2012-08-30 Mitsubishi Heavy Ind Ltd Battery module
US8276695B2 (en) 2007-12-25 2012-10-02 Byd Co. Ltd. Battery electrode sheet
CN102779967A (en) * 2011-05-10 2012-11-14 通用汽车环球科技运作有限责任公司 Battery cell with integrated busbar
JP2013504288A (en) * 2009-09-04 2013-02-04 リ−テック・バッテリー・ゲーエムベーハー Protection device for galvanicel
JP2013507749A (en) * 2009-10-13 2013-03-04 エルジー・ケム・リミテッド Battery module with excellent structural stability
KR101245285B1 (en) 2011-04-15 2013-03-19 주식회사 엘지화학 Apparatus for sensing temperature of battery module and Apparatus and method of managing battery pack using it
US8420254B2 (en) 2007-12-25 2013-04-16 Byd Co. Ltd. End cover assembly for an electrochemical cell
JP2013070558A (en) * 2011-09-26 2013-04-18 Panasonic Corp Independency power supply using container
JP2013524405A (en) * 2010-03-26 2013-06-17 ダイムラー・アクチェンゲゼルシャフトDaimler AG Battery with multiple individual cells
JP2013536542A (en) * 2010-07-02 2013-09-19 ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングRobert Bosch Gmbh Method for thermally isolating battery cells in case of failure
JP2013539179A (en) * 2010-09-02 2013-10-17 バシウム・カナダ・インコーポレーテッド Current collector terminal for electrochemical cells
JP2014519153A (en) * 2012-01-03 2014-08-07 エルジー・ケム・リミテッド Battery pack and connecting bar applied to it
JP2014520367A (en) * 2011-06-17 2014-08-21 エルジー・ケム・リミテッド Secondary battery component and method for manufacturing the same, and secondary battery and multi-battery system manufactured using the component
JP2014523064A (en) * 2011-06-17 2014-09-08 エルジー・ケム・リミテッド Soldering connector, battery module including the same, and battery pack
CN104115309A (en) * 2012-05-08 2014-10-22 株式会社Lg化学 Electrode lead and secondary battery including same
JP2014530456A (en) * 2011-09-16 2014-11-17 エルジー・ケム・リミテッド Secondary battery component, method of manufacturing the same, secondary battery manufactured using the component, and assembled secondary battery device
CN104303336A (en) * 2012-08-02 2015-01-21 株式会社Lg化学 Secondary-battery connecting part, and battery module and battery pack including same
KR101776325B1 (en) 2011-10-25 2017-09-08 현대자동차주식회사 Current interrupt device for high voltage battery of vehicle
KR101914559B1 (en) 2012-02-03 2018-11-02 삼성에스디아이 주식회사 Battery Pack

Cited By (59)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8007935B2 (en) 2006-10-30 2011-08-30 Byd Co., Ltd. Plate assembly, core and lithium ion battery
US8178225B2 (en) 2007-11-29 2012-05-15 Byd Co., Ltd. Battery and preparation method thereof
US8178230B2 (en) 2007-12-18 2012-05-15 Byd Co., Ltd. Battery pack
US8399116B2 (en) 2007-12-25 2013-03-19 Byd Co. Ltd. Optimized dimensional relationships for an electrochemical cell having a coiled core
US8865335B2 (en) 2007-12-25 2014-10-21 Byd Co. Ltd. Electrochemical storage cell
US20140141316A1 (en) * 2007-12-25 2014-05-22 Byd Company Limited Construction of electrochemical storage cell with conductive block
JP2011508391A (en) * 2007-12-25 2011-03-10 ビーワイディー カンパニー リミテッド Protective cover for battery cell end cap assembly
JP2011510433A (en) * 2007-12-25 2011-03-31 ビーワイディー カンパニー リミテッド Battery system for a vehicle having a separable connection
US20140141297A1 (en) * 2007-12-25 2014-05-22 Byd Company Limited Construction of electrochemical storage cell with conductive bridge
EP2618397B1 (en) * 2007-12-25 2017-02-08 BYD Company Limited Battery system for a vehicle with severable connections
US20140141315A1 (en) * 2007-12-25 2014-05-22 Byd Company Limited Construction of electrochemical storage cell with expansion member
US8092936B2 (en) 2007-12-25 2012-01-10 Byd Co. Ltd. Electrochemical cell having a coiled core
US9741996B2 (en) 2007-12-25 2017-08-22 Byd Co. Ltd. Construction of electrochemical storage cell
US10147930B2 (en) 2007-12-25 2018-12-04 Shenzhen Byd Auto R&D Company Limited Construction of electrochemical storage cell with conductive block
JP2013254739A (en) * 2007-12-25 2013-12-19 Byd Co Ltd Battery system
US8193770B2 (en) 2007-12-25 2012-06-05 BYD Co. Ltd Battery system for a vehicle having an over-current/over-temperature protective feature
US8202644B2 (en) 2007-12-25 2012-06-19 Byd Co. Ltd. Protection cover for an end cap assembly of a battery cell
JP2013232433A (en) * 2007-12-25 2013-11-14 Byd Co Ltd Battery system
US8276695B2 (en) 2007-12-25 2012-10-02 Byd Co. Ltd. Battery electrode sheet
US10381632B2 (en) 2007-12-25 2019-08-13 Shenzhen Byd Auto R&D Company Limited Construction of electrochemical storage cell with conductive bridge
US8420254B2 (en) 2007-12-25 2013-04-16 Byd Co. Ltd. End cover assembly for an electrochemical cell
US8383257B2 (en) 2007-12-25 2013-02-26 Byd Co. Ltd. Electrochemical storage cell with blow out vents
US8404379B2 (en) 2007-12-25 2013-03-26 Byd Co., Ltd. Vehicle with a battery system
JP2009211998A (en) * 2008-03-05 2009-09-17 Nissan Motor Co Ltd Cooling device for battery pack
JP2010049842A (en) * 2008-08-19 2010-03-04 Sanyo Electric Co Ltd Battery pack for vehicle
JP2012512504A (en) * 2008-12-16 2012-05-31 インパクト クリーン パワー テクノロジー スポルカ アキジナ Thermal stabilization electric battery module
WO2010082254A1 (en) * 2009-01-16 2010-07-22 トヨタ自動車株式会社 Electrical storage device
JP2010165597A (en) * 2009-01-16 2010-07-29 Toyota Motor Corp Energy storage device
US8062785B2 (en) 2009-07-17 2011-11-22 Panasonic Corporation Battery module and battery pack using the same
WO2011007547A1 (en) * 2009-07-17 2011-01-20 パナソニック株式会社 Battery module and battery pack using same
JP2011034775A (en) * 2009-07-31 2011-02-17 Sanyo Electric Co Ltd Assembled battery cooling structure and battery system
JP2013504288A (en) * 2009-09-04 2013-02-04 リ−テック・バッテリー・ゲーエムベーハー Protection device for galvanicel
US9627664B2 (en) 2009-10-13 2017-04-18 Lg Chem, Ltd. Battery module of excellent structural stability
US8810080B2 (en) 2009-10-13 2014-08-19 Lg Chem, Ltd. Battery module of excellent structural stability
JP2013507749A (en) * 2009-10-13 2013-03-04 エルジー・ケム・リミテッド Battery module with excellent structural stability
JP2011096536A (en) * 2009-10-30 2011-05-12 Sanyo Electric Co Ltd Power supply device and vehicle with the same
JP2013524405A (en) * 2010-03-26 2013-06-17 ダイムラー・アクチェンゲゼルシャフトDaimler AG Battery with multiple individual cells
US9214704B2 (en) 2010-07-02 2015-12-15 Robert Bosch Gmbh Thermal decoupling of battery cells in the case of a malfunction
JP2013536542A (en) * 2010-07-02 2013-09-19 ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツングRobert Bosch Gmbh Method for thermally isolating battery cells in case of failure
JP2013539179A (en) * 2010-09-02 2013-10-17 バシウム・カナダ・インコーポレーテッド Current collector terminal for electrochemical cells
JP2012164463A (en) * 2011-02-04 2012-08-30 Mitsubishi Heavy Ind Ltd Battery module
KR101245285B1 (en) 2011-04-15 2013-03-19 주식회사 엘지화학 Apparatus for sensing temperature of battery module and Apparatus and method of managing battery pack using it
CN102779967A (en) * 2011-05-10 2012-11-14 通用汽车环球科技运作有限责任公司 Battery cell with integrated busbar
US9118069B2 (en) 2011-05-10 2015-08-25 GM Global Technology Operations LLC Battery cell with integrated busbar
JP2014523064A (en) * 2011-06-17 2014-09-08 エルジー・ケム・リミテッド Soldering connector, battery module including the same, and battery pack
US10256454B2 (en) 2011-06-17 2019-04-09 Lg Chem, Ltd. Component for secondary battery and manufacturing method thereof, and secondary battery and multi-battery system manufactured by using the component
JP2014520367A (en) * 2011-06-17 2014-08-21 エルジー・ケム・リミテッド Secondary battery component and method for manufacturing the same, and secondary battery and multi-battery system manufactured using the component
EP2757615A4 (en) * 2011-09-16 2015-06-24 Lg Chemical Ltd Secondary battery component, manufacturing method thereof, secondary battery manufactured using component, and assembled secondary battery device
US9118072B2 (en) 2011-09-16 2015-08-25 Lg Chem, Ltd. Component for secondary battery and manufacturing method thereof, and secondary battery and multi-battery apparatus manufactured by using the component
JP2014530456A (en) * 2011-09-16 2014-11-17 エルジー・ケム・リミテッド Secondary battery component, method of manufacturing the same, secondary battery manufactured using the component, and assembled secondary battery device
JP2013070558A (en) * 2011-09-26 2013-04-18 Panasonic Corp Independency power supply using container
KR101776325B1 (en) 2011-10-25 2017-09-08 현대자동차주식회사 Current interrupt device for high voltage battery of vehicle
JP2014519153A (en) * 2012-01-03 2014-08-07 エルジー・ケム・リミテッド Battery pack and connecting bar applied to it
KR101914559B1 (en) 2012-02-03 2018-11-02 삼성에스디아이 주식회사 Battery Pack
JP2015513205A (en) * 2012-05-08 2015-04-30 エルジー・ケム・リミテッド Electrode lead and secondary battery including the same
CN104115309A (en) * 2012-05-08 2014-10-22 株式会社Lg化学 Electrode lead and secondary battery including same
JP2015519715A (en) * 2012-08-02 2015-07-09 エルジー・ケム・リミテッド Secondary battery connecting part, battery module including the same, and battery pack
EP2827404A4 (en) * 2012-08-02 2015-10-07 Lg Chemical Ltd Secondary-battery connecting part, and battery module and battery pack including same
CN104303336A (en) * 2012-08-02 2015-01-21 株式会社Lg化学 Secondary-battery connecting part, and battery module and battery pack including same

Similar Documents

Publication Publication Date Title
JP5883944B2 (en) Battery module with improved safety and battery pack including the same
KR101825261B1 (en) Protective element, protective element fabrication method, and battery module in which protective element is embedded
US8481191B2 (en) Rigid cell separator for minimizing thermal runaway propagation within a battery pack
CN103460447B (en) Battery module and the busbar being applied to battery module
TWI596638B (en) Protection components
EP2725650B1 (en) Battery module having improved stability
JP6227569B2 (en) Battery system
KR100914839B1 (en) Battery Module of Improved Safety and Middle or Large-sized Battery Pack Containing the Same
KR101256071B1 (en) Rechargeable battery
US10026949B2 (en) Secondary battery and electrode lead assembly applied thereto
US9059459B2 (en) Secondary battery
JP5154454B2 (en) Battery module
KR101192077B1 (en) Secondary battery and battery pack using the same
KR100659856B1 (en) Pouch Type Li Secondary Battery
JP5344932B2 (en) Medium or large battery module
CA2297839C (en) In situ short-circuit protection system and method for high-energy electrochemical cells
KR101169205B1 (en) Middle or Large-sized Battery Pack of Improved Safety
JP5748380B2 (en) Battery pack with improved safety
KR100593127B1 (en) Circuit and device for protecting secondary battery
US9887413B2 (en) Battery pack and connecting bar applied thereto
KR100906253B1 (en) Secondary Battery Having Electrode With Self Cutting Part To Be Destructed On Application Of Over-Current
US8709621B2 (en) Rechargeable battery
US8749341B2 (en) External operation thermal protector
KR100670501B1 (en) Secondary battery
JP5355532B2 (en) Secondary battery and battery pack using the same