JPH10112299A - Battery module and set battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve inside core heat radiation by increasing weight and volume energy per battery module by externally fitting a plurality of short cylindrical electrodes into a hollow core at equal intervals and taking out power via the collector lead of each electrode. SOLUTION: A hollow core 1 is constituted of an aluminum inner cylinder 1a, and an outer cylinder 1b of an insulating material such as PE which is externally fitted to the outside. Each gourd-shaped planar module fitting and joining members 3a and 3b of copper and aluminum, etc., is fitted in the upper and lower end part sides of the hollow core 1 and the members 3a and 3b are connected with positive and negative electrode module terminals 4a and 4b taking out power of a battery module M. Between these module terminals 4a and 4b, three short cylindrical electrodes 5a to 5c holding active materials for battery between winding films are externally fitted at equal intervals. At each electrode 5a to 5c, collector leads 6a to 6f taking out each power are provided and are connected with the terminals 4a to 4b via collector lead fixing members 7a to 7d. Thus, energy per battery module is increased, and inside heat radiation is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery module and an assembled battery, and more particularly, to a battery module of an assembled battery used as a power source in an electric vehicle or the like.

[0002]

2. Description of the Related Art FIG. 10 is an external perspective view of an example of an assembled battery B used as a primary battery for a power source of a conventional electric vehicle. As shown in FIG. 10, the battery pack B has a battery case 101 in which a large number of battery modules 102 are incorporated, and the battery modules 102 are connected by a bus bar (connection terminal) 103 made of copper or the like.
A DC voltage of about 0 V is obtained. The bus bar 103 is connected to a terminal of the battery module 102 via a screw. Further, for safety reasons such as prevention of electric shock, each battery module 102 is covered with a cover (not shown).

[0003]

However, since a large number of heavy busbars and screws are required to construct the assembled battery, the total weight of the assembled battery becomes large, and it is necessary to obtain a high DC voltage. Assembles a large number of battery modules, so that the assembled battery is bulky. Therefore, the weight energy density and the volume energy density of the battery pack are low, which is not preferable for a battery pack for electric vehicles. Further, when power is taken out from the battery pack, heat is generated (particularly at high output), but the cover cannot sufficiently release heat.

Further, as shown in FIGS. 11A and 11B, when an assembled battery B is mounted on an electric vehicle, it is often mounted under the floor. In this case, since the battery pack B must be configured to be thin, the air circulation portion A for heat radiation becomes narrow, and it is difficult to secure a sufficient heat radiation route.
Therefore, an object of the present invention is to provide a battery module and an assembled battery with reduced weight, sufficient heat radiation, high weight energy density and high volume energy density.

[0005]

According to a first aspect of the present invention, there is provided a cylindrical body having an insulator, and a plurality of power generation unit cells externally fitted to the cylindrical body. And an outer cylinder case that integrally covers the plurality of unit cells externally fitted to the cylinder. According to the first aspect of the present invention, for example, as shown in FIG. Construct M. With such a configuration, a plurality of (for example, three) electrodes are built in one battery module M, and a high voltage (for example, 1.5 V × 3 = 4 V) is obtained with one battery module M. be able to.

The invention according to claim 2 is characterized in that airtightness is ensured for each of the unit cells. Further, the invention according to claim 3 is characterized in that the airtightness securing means is formed by disposing a partition between the unit cells and caulking from the outside corresponding to the partition. According to a fourth aspect of the present invention, in the airtightness maintaining means, a partition is arranged between the unit cells, and a band is fastened from outside corresponding to the partition.

According to the present invention, airtightness between the unit cells is ensured by caulking or band fastening. With this airtightness, no liquid leakage or gas leakage occurs between the unit cells, and even if an abnormality occurs in one unit cell, there is no adverse effect on other unit cells.

Further, the invention according to claim 5 is characterized in that a refrigerant is caused to flow through the cylindrical body. According to the fifth aspect of the present invention, it is possible to prevent the temperature of the battery module from rising by flowing a refrigerant (for example, cool air of an air conditioner) through the cylinder.

The invention according to claim 6 is characterized in that a hole is formed in the cylinder so as to pass through the inside and outside of the cylinder. According to the sixth aspect of the present invention, even if gas is generated from the unit cell, the gas can be released to the outside through the hole.

According to a seventh aspect of the present invention, at least both ends of the battery module according to any one of the first to sixth aspects are held. According to the invention of claim 7, for example, as shown in FIG.
At least both ends of each battery module according to any one of claims 1 to 6 are fixed and held by support plates 11b and 11d. With this configuration, the battery module can be firmly fixed, and rigidity can be ensured even when a battery pack is configured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

(1) First Embodiment FIG. 1 is a longitudinal sectional view of a battery module M of this embodiment, FIG. 2A is a perspective view of a main part of the battery module M, and FIG. Is a top view. As shown in FIGS. 1 and 2A and 2B, the battery module M has a cylindrical hollow core 1.
And electrodes (unit cells) 5a to 5 externally fitted to the hollow core 1.
c, various members such as current collecting lead fixing members 7a to 7d,
Module connecting members 3a, 3 for interconnecting battery modules M with a cylindrical outer cylinder case 2 covering the various members.
b etc.

The hollow core 1 is configured such that an outer cylinder 1b made of an insulating material such as PE or PP is externally fitted to an outer cylinder 1a made of SUS, aluminum or the like. Copper, aluminum, and SUS are provided on the upper and lower ends of the hollow core 1, respectively.
A substantially gourd-shaped plate-like inter-module connecting member 3a, 3b made of the same is fitted. The inter-module connecting members 3a and 3b are electrically connected to the positive-polarity module terminal 4a and the negative-polarity module terminal 4b respectively fitted to the hollow core 1. The module terminals 4a,
4b is a terminal for taking out the power of each battery module M.

Between the module terminals 4a and 4b, an insulating material film such as PE or PP is wound in a roll shape, and three active materials for a battery are sandwiched between the wound films. Cylindrical electrode (unit cell, power generator) 5a,
5b and 5c are fitted to the hollow core 1 at equal intervals.

The upper and lower electrode sides of the upper electrode 5a
A tongue-shaped current collecting lead 6a for the positive electrode and a current collecting lead 6b for the negative electrode, which extract electric energy from a. Similarly, current collecting leads 6c and 6d are arranged on the upper and lower end surfaces of the central electrode 5b, and current collecting leads 6e and 6f are arranged on the upper and lower end surfaces of the lower electrode 5c. The upper and lower end surfaces of each current collecting lead are electrically connected to the current collecting lead section fixing member 7 and the electrode 5 by laser or welding, respectively.

The module terminal 4a disposed above
A current collector lead fixing member 7a formed of copper, aluminum, SUS, or the like and formed in a lower half of a solo van ball for electrically connecting the module terminal 4a and the current collector lead 6a is provided between the module lead 4a and the current collector lead 6a. Between the module terminal 4b, which is externally fitted and disposed below, and the current collecting lead portion 6f, a similar current collecting lead portion fixing member 7b in the upper half of a solo ban ball is externally fitted. A similar current collecting lead fixing member 7c is fitted between the current collecting leads 6b and 6c, and a similar current collecting lead fixing member 7d is formed between the current collecting leads 6d and 6e. Fitted outside. An insulating film 8 made of PE, PP, or the like is affixed to the inner surface of the outer cylinder case 2 that covers various members such as the electrodes 5a to 5c. The upper and lower ends of the outer case 2 are formed in a sealed state with respect to the module terminals 4a and 4b, respectively.

The contact portions between the outer peripheral portions of the current collecting lead portion fixing members 7c and 7d and the inner surfaces of the outer cylinder case 2 and the insulating film 8 are caulked from the outer peripheral portion of the outer cylinder case 2 and each electrode 5a , 5b, 5c as a unit (unit cell S)
The airtightness of each unit cell S is ensured. That is,
Including the current collecting lead portion fixing members 7a and 7b at the upper and lower ends,
Each of the current collecting lead portion fixing members 7a to 7d is
(Electrode) plays a role of a partition wall for airtight separation.

FIG. 3 shows an assembled battery B1 incorporating a large number (for example, 12) of the battery modules M configured as described above.
4 (A), (B) and (C) are a perspective view of the battery pack B1 and an example of the arrangement of the battery modules M when viewed from the direction of the arrow Y.

As shown in FIGS. 3, 4A and 4B,
A strong box 11a is constituted by a structural member made of iron, SUS, aluminum or the like. The box 11a is made of iron,
An upper support plate 11b, a middle support plate 11c, and a lower support plate 11d made of SUS, aluminum or the like are provided.
By b and 11d, the upper end and the lower end of the hollow core 1 of each battery module M are fixed via an insulating sleeve 12, respectively. The center of each battery module M is fixed by a middle support plate 11c. The battery modules M are connected in series by inter-module connecting members 3a and 3b, and an assembled battery terminal 14 for connection to the outside is provided at the upper right and left corners of the assembled battery B1. Reference numeral 13 denotes an assembled battery case made of aluminum, SUS, iron, or the like that covers the assembled battery B1.

Next, the operation will be described. The upper end, the center, and the lower end of the battery module M or the hollow core 1 are supported by the upper support plate 11b, the middle support plate 11c, and the lower support plate 11d, respectively. (A) and (B)), sufficient strength can be ensured.

Since, for example, three electrodes can be formed in the battery module M, the voltage generated per battery module M increases. That is, while the conventional battery module shown in FIG. 10 has 1.5 V, the battery module M of the present embodiment has 1.5 V × 3 = 4.5 V. Therefore, according to the present embodiment, when the same voltage is generated, both the weight and the volume can be reduced, so that the weight energy and the volume energy can be improved.

The number of electrodes in the battery module is 4
Of course, it is also possible to configure more than one. The battery module M can be cooled by flowing cooling air through the hollow portion of the hollow core 1. In particular, when the temperature rises to take out a large output from the battery module (for example, when climbing a hill), for example, cool air for an air conditioner may be made to flow. Further, as shown in FIG. 4 (C), if the battery modules M are staggered, the height H1 of the assembled battery can be reduced.
Can be further reduced.

(2) Second Embodiment The difference between the present embodiment and the first embodiment is that an abnormality detecting means for detecting an abnormality of the battery module M is provided. FIG. 5 is a longitudinal sectional view of the battery module M1 of the embodiment, and FIG. 6 is a block diagram of an abnormality detection circuit. Note that the same reference numerals are given to the already described portions, and redundant description is omitted.

As shown in FIG. 5, on the inner surface side of the hollow core 1, an abnormality detecting circuit 21a for detecting an abnormality for each unit cell S,
21b, 21c are provided, and each circuit 21a, 21b, 2
LED (light emitting diode) 23a, 23b, 23c which lights up when abnormality is detected is attached to 1c.

Terminals 25a to 25d are protruded from the inner surfaces of the current collecting lead portion fixing members 7a to 7d toward the inner surface of the hollow core 1, and the terminals 25a to 25d and the abnormality detection circuits 21a are provided.
Are connected by connection cables 22a, 22b,.... An optical sensor 26 composed of a phototransistor or the like is provided at the upper end of the hollow core 1,
Lighting of 23a, 23b and 23c is detected. FIG.
As shown in (1), a voltmeter V is connected to each unit cell S of the battery module M, and the detected value of the voltmeter V is A / D converted and input to the CPU. Then, the LED 23 is turned on by the CPU via the I / O.

In this way, overcharging of the unit cell S,
When overdischarge or abnormal rise in cell temperature occurs, the LED 23 of the unit cell S corresponding to the abnormal condition is turned on, the lighting light is detected by the optical sensor 26, and an alarm is issued by a buzzer (not shown) or the like via the CPU. Can be Therefore, when an abnormality occurs in the battery module, a countermeasure can be immediately taken. Since the lighting of the LED 23 occurs inside the hollow core 1, even light having a weak luminous intensity can be easily detected. Further, since the abnormality detection circuit 21 is provided inside the hollow core 1, even if an abnormal external force is applied to the battery pack B1 by mistake, the abnormality detection circuit 21 is unlikely to cause a failure.

(3) Third Embodiment A difference between this embodiment and the first embodiment (see FIG. 4) is that a forced cooling means is provided. As shown in FIG. 7, an intake duct 31 for introducing a refrigerant is disposed on the upper end side of the hollow core 1 of each battery module M.
Cool air from an air conditioner, a radiator, or the like flows into each hollow core 1 from the air conditioner 1 through an introduction pipe 31a.

At the lower end of the hollow core 1 of each battery module M, a collection duct 32 for collecting refrigerant is arranged, and cooled exhaust gas is collected through each collection pipe 32a. When a normal electric vehicle (see FIG. 11A) travels, cooling air is applied to the battery module M from outside.

At the time of high output (for example, when climbing a hill), the heat generated by the battery module M is increased.
The refrigerant flows through the path of the introduction pipe 31a, the hollow core 1, the recovery pipe 32a, and the recovery duct 32 to forcibly cool the battery module M. In this way, the battery module M is not overheated even at the time of high output, so that a decrease in output can be prevented.

(4) Fourth Embodiment In this embodiment, as shown in FIG. 8, a band 35 made of SUS or the like is wound around the outer peripheral portion of the caulking portion of the outer cylinder case 2 and tightened to loosen the caulking. It is not to be. In this way, the reliability of confidentiality of each cell is further improved. Further, when assembling the assembled battery using the band 35 (see FIGS. 4A, 4B, and 4C), the battery module M can be fixed.

(5) Fifth Embodiment This embodiment is a case where the gas generated in the cell S is guided to the outside through the hollow core.

As shown in FIG. 9, holes 1Aa1, 1Aa2, 1Ab1, and 1Ab2 are formed at regular intervals in the hollow core 1A, and the upper holes 1Aa1 and 1Aa2 are formed in the upper holes 1Aa1 and 1Aa2 by a predetermined gas pressure. Gas release valves 37a, 37 that open inward
b is attached. Similarly, the lower hole 1Ab1,1
Gas release valves 37c and 37d are attached to Ab2. Further, the current collecting lead portion fixing members 36a and 36b are formed so as to have a trapezoidal hollow section, and the opening side of the hollow portion is disposed so as to cover the holes 1Aa1, 1Aa2, 1Ab1, and 1Ab2.

With this configuration, when the gas generated in the unit cell S exceeds a predetermined value, the gas release valve is pushed open and the trapezoidal hollow portion of the cell S and the current collecting lead fixing member is opened. Since gas flows only in one direction, the gas is guided to the outside via the hollow core 1A.

[0034]

As described above, according to the invention described in each of the claims, a plurality of power generation unit cells are externally fitted to the cylindrical body,
The battery module is configured such that the unit cell is covered with an outer cylinder case and airtightness is maintained for each unit cell. Therefore, weight energy and volume energy per one battery module are improved, and The heat dissipation is improved due to the good ventilation inside.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a battery module according to a first embodiment of the present invention.

FIG. 2A is a perspective view of a main part of the first embodiment,
(B) is a top view.

FIG. 3 is a longitudinal sectional view of an assembled battery constituted by the battery module of the first embodiment.

FIG. 4A is a perspective view of an assembled battery including the battery module of the first embodiment, and FIGS. 4B and 4C are arrows Y;
It is the side view seen from the direction.

FIG. 5 is a longitudinal sectional view of the second embodiment.

FIG. 6 is a block diagram of an abnormality detection circuit used in the second embodiment.

FIG. 7 is a longitudinal sectional view of the third embodiment.

FIG. 8 is a vertical sectional view of a main part of the fourth embodiment.

FIG. 9 is a vertical sectional view of a main part of the fifth embodiment.

FIG. 10 is an external perspective view of a conventional battery pack.

FIG. 11A is a diagram showing a mounting position of a battery pack in a conventional electric vehicle, and FIG. 11B is a perspective view of the battery pack.

[Explanation of Signs] B Battery assembly M Battery module 1 Hollow core 2 Case (outer cylinder case) 3 Module connecting member 4 Module terminal 5 Electrode (unit cell) 6 Current collecting lead 7 Current collecting lead fixing member 8 Insulating film 11a Box 11b, 11c, 11d Support Plate 12 Sleeve 23 LED 26 Optical Sensor 31 Refrigerant Intake Duct 32 Refrigerant Recovery Duct 35 Caulking Band

Claims (7)

[Claims] A cylindrical body provided with an insulator; a plurality of power generation unit cells externally fitted to the cylindrical body; and an outer body integrally covering the plurality of unit cells externally fitted to the cylindrical body. A battery module, comprising: a tubular case. 2. The battery module according to claim 1, wherein airtightness is ensured for each unit cell. 3. The battery module according to claim 2, wherein said airtightness securing means has a partition wall between said unit cells, and is caulked from outside corresponding to said partition wall. 4. The battery module according to claim 2, wherein the airtightness securing means is provided with a partition wall between the unit cells, and band-tightened from outside corresponding to the partition wall. 5. The battery module according to claim 1, wherein a coolant is caused to flow through the cylinder. 6. The cylinder according to claim 1, wherein a hole is formed in the cylinder to pass through the inside and the outside of the cylinder.
The battery module according to any one of the above. 7. An assembled battery, wherein at least both ends of the battery module according to claim 1 are held.