JPH07142069A - Battery assembly and its manufacture - Google Patents

Abstract

PURPOSE:To provide a battery assembly and its manufacturing method by which shaky state of a unit cell group installed in a case and damage or the like of the case when it is dropped by mistake can be prevented. CONSTITUTION:A battery assembly has a box-shaped case 1, plural unit cells 2 housed and arranged in the case 1, safety elements 6 (7 and 8) interposed and inserted in a connecting passage to the unit cells 2 electrically to each other and unit cell fixing means 3 which fixe the unit cells 2 in the case 1 and are composed of a specific resin layer. The manufacturing method is composed of a process to position, house and arrange the plural unit cells 2 and the necessary auxiliary safety elements 6, 7 and 8 in the box-shaped case 1 and a process to fix the unit cells 2 to an inner wall surface of the case 1 by hardening a monoliquid epoxy resin type composition arranged in a void part at least of one side surface of the unit cells 1 housed and arranged in the case 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembled battery and a manufacturing method thereof, and more particularly to an assembled battery suitable for a power source of electronic devices and a manufacturing method thereof.

[0002]

2. Description of the Related Art In so-called electronic equipment, from the viewpoint of higher output or higher functionality, as a driving power source, a plurality of unit cells are attached together with accompanying safety elements,
For example, an assembled battery is used which is housed in a box-shaped case and connected in series or in parallel.
Here, examples of the assembled battery include a cylindrical shape and a prismatic shape,
In addition, the box-shaped case is generally acrylic-Butagen-
It is made of styrene resin, polycarbonate resin, polyphenylene oxide resin, or the like. In addition, in order to prevent backlash during handling and damage due to impact when accidentally dropped, this type of assembled battery is generally used as follows for the unit cells housed in the case. Means or configurations are adopted. That is, for example, a double-sided adhesive tape is attached to the inner wall surface of the case, or an adhesive or a pressure-sensitive adhesive is applied,
The unit cell group housed and arranged in the case is fixed by the adhesive action or the adhesive action. Examples of the adhesive or pressure-sensitive adhesive include solvent type, aqueous type, hot melt type, and chemical reaction type.

[0003]

By the way, when a double-sided adhesive tape is used to fix the unit cell group, if the unit cell has a cylindrical shape, the unit cell has improved adhesion to the inner wall surface of the case, and also when dropped. In order to effectively absorb the impact energy of (in this case, regardless of the shape of the unit cell), it is necessary to use a thick double-sided adhesive tape. However, in the current situation where compactness of the assembled battery is required, the storage size of at least one safety element selected from the unit cell group, terminal block, thermistor, thermostat, temperature fuse, etc. in the case is slightly small. Since the double-sided pressure-sensitive adhesive tape is limited in space because it is designed with a margin, it is not possible to sufficiently achieve the above-mentioned adhesion and effective absorption of impact energy. Is the actual situation.

On the other hand, fixing with an adhesive or a pressure-sensitive adhesive has the following problems. That is, since the solvent-type adhesive or pressure-sensitive adhesive contains a solvent such as vinyl acetate, methyl ethyl ketone, or toluene, the resin case is attacked by these solvents and further solvent cracks are generated, so that the case may be damaged. It may be damaged. In addition, since the base of the water-based adhesive or pressure-sensitive adhesive is vinyl acetate or ethylene-vinyl acetate, it is essentially inferior in heat resistance and cannot withstand the internal heat generation up to about 80 ° C. In the case of the adhesive or pressure-sensitive adhesive of item (1), there is a problem that the unit cell and an accessory electronic component are likely to be adversely affected by the heat during heating and melting.
Furthermore, in the case of a chemical reaction type adhesive or pressure sensitive adhesive, for example, an epoxy resin type, there is a disadvantage that the so-called set time is long and the process cannot be immediately transferred to the step after the adhesion work. In this case, conversely, the time set is too short to make it difficult to carry out the bonding work such as sufficient positioning, and it is not practical in terms of impact resistance.

The present invention has been made in consideration of the above circumstances, and completely prevents (avoids) rattling of a unit cell group mounted (arranged) in a case and damage to the case when it is accidentally dropped. It is an object of the present invention to provide an assembled battery exhibiting a highly reliable function and a manufacturing method thereof.

[0006]

The assembled battery according to the present invention comprises:
A box-shaped case, a plurality of unit cells housed in the case, a safety element inserted in a connection path of the housed unit cells, and the unit cells housed in the case are fixed in the case. A unit cell fixing means, wherein the unit cell fixing means is formed by a resin layer containing an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin, and The manufacturing method of such an assembled battery includes a step of positioning and accommodating a plurality of unit cells and required accessory parts in a box-shaped case,
A one-pack type epoxy resin containing an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin in the void formed by the outer peripheral surface of at least part of the unit cell housed in the case and the inner wall surface of the case. It is characterized by comprising a step of disposing the system composition and a step of curing the disposed one-pack type epoxy resin composition to fix the unit cell to the inner wall surface of the case.

That is, according to the present invention, an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin are essential components for fixing a plurality of unit cells housed and arranged in a box-shaped case. The main point is to use a liquid epoxy resin composition. The present invention exhibits good heat resistance and adhesiveness when adhered / fixed with the one-pack type epoxy resin composition, while the property after curing is also a rubber-like elastic body so that shocking energy can be obtained. It was made based on this finding by finding effective absorption.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol AD type epoxy resin. Further, ketimine is represented by the following general formula, and it is useful that the imino group in the ketimine molecule is reacted with styrene oxide or glycidyl ethers. Regarding the ketimine, JP-A-4-1202
The publication is described in detail.

[0009]

[Chemical 1] (Wherein R ₁ , R ₂ , R ₃ and R ₄ are the same or different hydrogen, an alkyl group having 2 to 6 carbon atoms or a phenyl group, X ₁ , X ₂ and X ₃ are the same or different carbon numbers 2 to
6 alkylene groups, m is an integer of 0 or 1).

Further, the modified silicone resin is a polyether copolymer having a hydrolyzable silicon functional group represented by the following general formula at the molecular end.

[0011]

[Chemical 2] (In the formula, R ₅ is a monovalent hydrocarbon group having 1 to 12 carbon atoms,
R ₆ is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and n is an integer of 0 to 2).

Furthermore, examples of the curing catalyst for the modified silicone resin include the following.

These epoxy resins, ketimines,
The composition ratio of modified silicone resin and curing catalyst for modified silicone resin is generally 20 to 100 parts by weight of epoxy resin, 20 to 40 parts by weight of ketimine, 100 parts by weight of modified silicone resin, and 6 parts by weight of curing catalyst for modified silicone resin. It is desirable to select below. If necessary, for example, a disilane compound may be used in combination to improve the adhesiveness, or various fillers or additives may be used in combination in consideration of mechanical properties and heat resistance. .

[0014]

In the present invention, a plurality of unit cells housed (mounted) in the case are provided in the case by the resin layer containing the epoxy resin, ketimine, the modified silicone resin and the curing catalyst for the modified silicone resin. It has a fixed configuration. The one-pack type epoxy resin composition develops viscosity within a few minutes after contact with a resin case surface (by coating / filling, etc.), so that the next work can be performed almost without waiting time. . Further, in the expression of the above-mentioned viscosity and also in the subsequent adhesion / fixing, not only does the adhesive strength exhibit a high initial rise, but at the stage of contributing to the adhesion / fixing to prevent rattling, in other words, the rubber-like elastic body in the cured state. Since the shock energy caused by dropping is effectively absorbed, damage to the case or the assembled battery due to the shock can be easily avoided. In other words, it can be said that it greatly contributes to the reliability and long life of the assembled battery.

[0015]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view showing a perspective view of an example of the essential structure of an assembled battery according to the present invention. Reference numeral 1 is a box-shaped resin case, and 2 is a cylindrical shape housed in the case 1. The unit cells (plurality) 3 are filled in a gap between one side surface side of the plurality of unit cells 2 which are stored and arranged and the inner wall surface of the case 1.
Is a resin layer that is fixed inside the case 1. In this configuration example, the case 1 includes a box-shaped main body (lower case) 1a made of acrylic-butadiene-styrene resin and a lid (upper case) also made of acrylic-butadiene-styrene resin.
1b, and the resin layer 3 is formed by a system containing an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin as an essential component. In FIG. 1, 4 is a connection terminal such as + pole, − pole, thermistor, 5 is an electrical connection path, 6 is a thermistor element, 7 is a thermostat, and 8 is a temperature fuse. As a safety element of the battery, it is additionally inserted and installed in the electrical connection path 5 and may not necessarily include all the elements.

The assembled battery having the above structure can be easily manufactured as follows. First, a box-shaped main body (lower case) 1a to which the required connection terminals 5 and electrical connection paths 5 have been attached is prepared in advance. The unit cell 2 is positioned and placed / installed, and the thermistor 6, thermostat 7, temperature fuse 8 and other safety elements are also placed / installed.

On the other hand, for example, 35 parts by weight of an epoxy resin, ketimine (2,4,12,14-tetramethyl-5-pentadecadiene
10 parts by weight of a product obtained by reacting 1 mol with 1 mol of styrene oxide at 150 ° C. for 2 hours), 100 parts by weight of modified silicone resin, curing catalyst for modified silicone resin (eg tin octylate, tin stearate) 2 parts by weight, vinyltrimethoxysilane 5 parts by weight, silane compound
2 parts by weight, 130 parts by weight of calcium carbonate and titanium oxide
A one-pack type epoxy resin composition was prepared by mixing 20 parts by weight as a component.

The resin-based composition is placed in the box-shaped lower case 1a in a space between the unit cells 2 on one side surface (upper surface side) of the unit cells 2 and the one-component epoxy is used. After filling and arranging the resin composition, the upper case 1b is positioned and arranged on the surface on which the one-component epoxy resin composition is filled and arranged to assemble the assembled battery. Then, the assembled battery is left at room temperature for 2 hours to cure the filled and arranged one-pack type epoxy resin composition, so that the side surface of the unit cell 2 is adhered and fixed to the inner wall surface of the case 1. The assembled battery was obtained.

The battery pack manufactured as described above (weight: 14
5g) from the height of 50cm, 75cm, or 100cm, set the falling directions X, Y, Z as shown in perspective in Fig. 2, and let them fall naturally on the concrete surface to evaluate the damage condition. Shown in the table. In the table, ◯ marks indicate no damage, Δ marks indicate few cracks, and X marks indicate many cracks.

For comparison, the one-component epoxy resin-based composition in the above construction is used to form a thickness on both sides instead of adhering and fixing the side surface of the unit cell 2 to the inner wall surface of the case 1.
A 0.1 mm double-sided adhesive tape intervenes, and the battery pack configured to adhere and fix the side surface of the unit cell 2 to the inner wall surface of the case 1 with this double-sided adhesive tape (corresponding to the conventional example) drops under the same conditions as above. The results of the evaluation are also shown in the table.

Table Drop height 50 cm 75 cm 100 cm Drop direction X Y Z X Y Y Z X Y Z Example Example ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Comparative Example × △ ○ × × △ × × × The present invention is carried out as described above. The invention is not limited to the configuration and the manufacturing means illustrated in the examples, and it is needless to say that other modifications can be made without departing from the gist of the present invention.

[0023]

As can be seen from the above description of the embodiments, according to the present invention, the rattling of the unit cell in the handling process can be easily and surely prevented, and even if it is accidentally dropped. Since the shock received at that time is effectively absorbed, damage to the case and eventually damage to the battery pack itself, loss of function, etc. are completely eliminated or prevented. Therefore, not only the functional reliability is improved, but also the productivity and the yield are improved in the manufacturing process.
The cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a perspective view of a configuration example of a main part of an assembled battery according to the present invention.

FIG. 2 is a perspective view showing a falling direction in a drop damage evaluation of a battery pack.

[Explanation of symbols]

1… Box-shaped case 1a… Lower case 1b… Upper case
2 ... Unit cell 3 ... Fixing / adhesive resin layer 4 ... Thermistor 5 ... Thermostat 6 ... Temperature fuse

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display H01M 10/42 Z

Claims (2)

[Claims] 1. A box-shaped case, a plurality of unit cells housed and arranged in the case, a safety element inserted and arranged in an electrical connection path of the housed and arranged unit cells, and the housed case. A unit cell fixing means for fixing the arranged unit cells in a case, wherein the unit cell fixing means is formed by a resin layer containing an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin. An assembled battery characterized in that 2. A step of electrically connecting and positioning and storing a plurality of unit cells and required safety elements in a box-shaped case, and at least a part of the unit cells stored and arranged in the case. A step of disposing a one-part epoxy resin composition containing an epoxy resin, ketimine, a modified silicone resin and a curing catalyst for the modified silicone resin in the void formed by the outer peripheral surface and the inner wall surface of the case; And a step of fixing the unit cell to the inner wall surface of the case by curing the epoxy resin-based composition.