JP7047733B2 - Battery module - Google Patents

Description

The present disclosure relates to battery modules.

A battery module in which a plurality of batteries are stacked is known. In such battery modules, especially in-vehicle battery modules, from the viewpoint of preventing the positions of the batteries from shifting due to vibration, impact, etc., and ensuring the battery life and output performance, multiple stacked batteries are used from both ends. Restraint pressure is applied.

Examples of such a battery module include the battery modules disclosed in Patent Documents 1 to 4.

Patent Document 1 describes a plurality of battery laminates laminated to each other, a positive electrode end plate and a negative electrode end plate arranged at one end and the other end of the battery laminate, and a band-shaped binding member for binding these. The battery module having the above is disclosed. The document discloses a configuration in which a member in contact with a binding member has a binding recess.

Patent Document 2 discloses a first end plate, a second end plate, a plurality of fuel cells interposed between the first end plate and the second end plate, surrounds the plurality of fuel cells, and applies a compressive force to the plurality of fuel cells. A fuel cell stack assembly with a compression band is disclosed. The document discloses that if the compression means for compressing the fuel cell stack assembly is sufficiently elastic and elastic, it can be stretched for the purpose of adapting the compression means around the stack.

Patent Document 3 is a fuel cell stack fastening device, the fuel cell stack including a pair of end plates and a plurality of fastening bands extending in the stacking direction of the fuel cell stack and pressurizing the end plates at a set pressure. Discloses the fastening device of. The document discloses that methods such as bolts, rivets, and welding can be used as means for fixing the end plate to the fastening band.

Patent Document 4 discloses a fuel cell laminate having at least one compression band surrounding the end plate assembly and the inserted fuel cell assembly. The document discloses that compressive forces are applied to promote sealing and electrical contact between the layers forming the fuel cell laminate. The document also discloses that the length of the compression band is adjustable.

Japanese Unexamined Patent Publication No. 2010-244894 Japanese Patent Publication No. 2011-508383 Japanese Unexamined Patent Publication No. 2005-142145 Japanese Patent Publication No. 2001-504632

Battery modules, such as vehicle-mounted battery modules, may be required to be industrially mass-produced. Therefore, it is preferable to design the battery module in a configuration and shape suitable for manufacturing.

On the other hand, the volumetric energy density of the battery module is considered including the volume of members other than the battery, such as the end plate and the restraint band, in addition to the volume of the battery itself. Therefore, it is not preferable to reduce the volumetric energy density of the battery module by designing the members other than the battery body in a configuration and shape suitable for manufacturing.

Therefore, it is required to improve the manufacturing efficiency of the battery module while suppressing the decrease in the volumetric energy density of the battery module.

An object of the present disclosure is to provide a battery module having high volumetric energy density and manufacturing efficiency.

The Discloser has found that the above task can be achieved by the following means:
<< Aspect 1 >>
Battery laminates with multiple building blocks stacked on top of each other,
A pair of end plates facing each other with the battery laminate sandwiched in the stacking direction of the constituent unit cells, and a pair of end plates bound in the stacking direction while pressurizing the battery laminate. Has a restraining band that is restraining,
The pair of the end plates
It has a concave restraint band fixing part that fixes the restraint band, and a concave claw hook part that can temporarily engage a jig for pulling the end plates in a direction that widens the distance between the pair of end plates. And the restraint band fixing portion and the claw hook portion do not overlap.
Battery module.
<< Aspect 2 >>
The battery module according to aspect 1, wherein the portion of the restraint band fixing portion in contact with the restraint band has a curved shape that is convex toward the opposite side of the battery laminate.
<< Aspect 3 >>
The battery module according to aspect 1 or 2, wherein the plurality of restraint band fixing portions and the plurality of claw hook portions are arranged alternately side by side with respect to the longitudinal direction of the end plate.
<< Aspect 4 >>
It has two or more of the restraint bands, and the cooling plate is arranged in the region between the two restraint bands and from one end plate to the other end plate.
The battery module according to any one of aspects 1 to 3.

According to the present disclosure, it is possible to provide a battery module having high volumetric energy density and manufacturing efficiency.

FIG. 1 is a schematic diagram showing a battery module 100a according to one embodiment of the present disclosure. FIG. 2 is a schematic view showing an end plate 20a in a battery module 100a according to one embodiment of the present disclosure. FIG. 3 is a schematic diagram showing an example of a manufacturing process of the battery module 100a according to one embodiment of the present disclosure. FIG. 4 is a schematic view showing an end plate 20b in a battery module different from the present disclosure. FIG. 5 is a schematic view showing a state in which a jig engaged with one end plate 20 is pulled in order to widen the space between the pair of end plates 20 when assembling the battery module. FIG. 6 is a schematic diagram showing an end plate 20c in a battery module 100c according to another embodiment of the present disclosure. FIG. 7 is a schematic diagram showing a battery module 100d according to still another embodiment of the present disclosure. FIG. 8 is a schematic diagram showing an end plate 20d in a battery module 100d according to still another embodiment of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described in detail. It should be noted that the present disclosure is not limited to the following embodiments, but can be variously modified and implemented within the scope of the main purpose of the disclosure.

In the specification of the present application, unless otherwise specified, the "stacking direction" means a direction in which a plurality of constituent unit cells constituting the battery laminate are laminated with each other.

Further, in the present specification, unless otherwise specified, the "occupied volume" is an area substantially occupied by the battery module on the substrate when the battery module is arranged on the substrate such as a vehicle. Refers to the volume of.

《Battery module》
The battery modules of the present disclosure include a battery laminate having a plurality of constituent unit cells stacked on each other, a pair of end plates facing each other with the battery laminate sandwiched in the stacking direction of the constituent unit cells, and a stacking direction. It also has a restraining band that binds the pair of end plates and restrains the battery laminate while pressurizing it.

Here, the pair of end plates has a restraint band fixing portion for fixing the restraint band, and a claw hook portion on which a jig for pulling the end plate can be temporarily engaged in a direction to widen the distance between the pair of end plates. are doing. Further, the restraint band fixing portion and the claw hook portion do not overlap.

Although not limited by the principle, the principle that the battery module of the present disclosure has high volumetric energy density and manufacturing efficiency is as follows.

As a method of manufacturing a battery module, for example, after binding a pair of end plates to each other, it is conceivable to widen the space between the pair of end plates and arrange a battery laminate between them.

In the battery module of the present disclosure, the end plate has a concave claw hook for which a jig for pulling the end plate in a direction to widen the distance between the pair of end plates can be temporarily engaged. As a result, by temporarily fixing the jig to the end plate and pulling the jig, it is easy to widen the distance between the pair of end plates with a large force. Further, since the claw hook portion has a concave shape, the jig is engaged with the end plate without increasing the occupied volume of the end plate as compared with the case where the jig is engaged with the surface of the end plate on the battery laminate side. be able to.

Further, in the battery module of the present disclosure, the restraint band fixing portion and the claw hook portion do not overlap. Therefore, in the battery module of the present disclosure, the jig can be engaged with the claw hook portion in a state where the restraint band is hung on the restraint band fixing portion of the end plate.

Further, in the battery module of the present disclosure, since the end plate has a concave restraint band fixing portion for fixing the restraint band, for example, the distance between the pair of end plates is widened, and the battery laminate is arranged between them. In some cases, it is possible to prevent the restraint band from shifting in the in-plane direction of the end plate.

As described above, in the battery module of the present disclosure, the jig is temporarily fixed to the claw hook portion of the end plate with the restraint band applied to the end plate, and the distance between the pair of end plates is widened by the jig. Since the pair of end plates can be pulled, it is easy to widen the distance between the pair of end plates during manufacturing, and the manufacturing efficiency is high. Further, since the claw hook portion has a concave shape, the occupied volume of the end plate does not increase due to the arrangement of the claw hook portion, so that the end plate can be miniaturized.

Thereby, the battery module of the present disclosure can improve the manufacturing efficiency while suppressing the decrease in the volumetric energy density.

The principle that the battery module of the present disclosure can improve the manufacturing efficiency while suppressing the decrease in the volumetric energy density will be described more specifically by using one embodiment of the battery module of the present disclosure.

FIG. 1 is a schematic diagram showing a battery module 100a according to one embodiment of the present disclosure.

In FIG. 1, the battery module 100a is a pair of end plates 20a facing each other with a battery laminate 10 having a plurality of constituent unit cells laminated to each other and a battery laminate 10 sandwiched in a stacking direction of the constituent unit cells. And, in the stacking direction, it has a restraint band 30 that binds the pair of end plates 20a and restrains the battery laminate 10 while pressurizing it.

Further, FIG. 2 is a schematic view showing an end plate 20a in the battery module 100a according to one embodiment of the present disclosure.

In FIG. 2, the end plate 20a has a concave restraint band fixing portion for fixing the restraint band, and a concave shape for temporarily engaging a jig for pulling a pair of end plates 20a in a direction of widening the distance between the end plates 20a. It has a claw hook portion 25a. Further, the restraint band fixing portion 23a and the claw hooking portion 25a do not overlap.

The battery module 100a according to one embodiment of the present disclosure can be efficiently manufactured by, for example, the method shown in FIG. 3 because the end plate 20a has the claw hook portion 25a.

FIG. 3 is a schematic diagram showing an example of a manufacturing process of the battery module 100a according to one embodiment of the present disclosure.

As shown in FIG. 3A, in this method, first, the pair of end plates 20a are bound by the restraint band 30.

Then, as shown in FIG. 3B, the jig 200 is engaged with the pair of end plates 20a. Then, the jigs 200 are subjected to a force in the direction indicated by the black arrow, that is, a force in the direction in which the pair of end plates 20a are separated from each other in the stacking direction to widen the distance between the pair of end plates 20a while forming the battery laminate 10. , Arranged between a pair of end plates 20a.

In FIG. 3B, the force is applied to both of the pair of end plates 20a, but while the one end plate 20a is temporarily fixed on the base material or the like with a jig, the other end plate 20a is applied. The distance between the pair of end plates 20a may be widened by applying a force in the direction indicated by the black arrow only.

Here, as the shape of the claw hook portion 25a, in addition to the shape as shown in FIG. 2, for example, it is conceivable to form a convex shape with respect to the end plate. However, when the claw hook portion 25a has such a shape, the width of the end plate 20a becomes larger than that of the battery laminate 10, and the occupied volume of the battery module 100a increases.

On the other hand, in the battery module 100a according to one embodiment of the present disclosure, as shown in FIG. 2, since the claw hook portion 25a of the end plate 20a has a concave shape, the claw hook portion 25a is arranged. As a result, there is no increase in the occupied volume of the battery module 100a.

Further, in the battery module 100a according to one embodiment of the present disclosure, as shown in FIG. 2, the claw hook portion 25a does not overlap with the restraint band fixing portion 23a. Therefore, the jig can be engaged with the claw hooking portion 25a in a state where the restraining band 30 is hung on the restraining band fixing portion 23a of the end plate 20a. Therefore, the end plate 20a can be miniaturized.

Thereby, the battery module of the present disclosure can improve the manufacturing efficiency while suppressing the decrease in the volumetric energy density.

On the other hand, in the case of a battery module different from the present disclosure, when manufacturing the battery module, after binding the pair of end plates to each other while maintaining the volume energy density of the battery module, the distance between the pair of end plates It is difficult to spread the battery stack and place the battery laminate in between.

FIG. 4 is a schematic view showing an end plate 20b in a battery module different from the present disclosure.

In FIG. 4, the end plate 20b has a restraint band fixing portion 23b, but does not have a claw hook portion. Therefore, it is difficult to arrange the battery laminate between the pair of end plates 20b while widening the distance between them. Further, when the portion other than the restraint band fixing portion 23b is projected, the jig is easily engaged with the end plate, but the volume energy density is lowered.

<end plate>
The end plate is a member capable of transmitting the pressure applied from the restraint band that pressurizes the battery laminate from the outside of the end plate to the battery laminate.

The pair of end plates face each other with the battery laminate sandwiched in the stacking direction. Further, the pair of end plates has a restraint band fixing portion for fixing the restraint band and a concave claw hook portion on which a jig for pulling the end plate can be temporarily engaged in a direction to widen the distance between the pair of end plates. have. The restraint band fixing portion and the claw hook portion do not overlap.

The material of the end plate is not particularly limited, and examples thereof include metals such as stainless steel, carbon fiber reinforced plastics, and fiber reinforced plastics such as glass fiber reinforced plastics.

The shape of the end plate may be any shape capable of transmitting the pressure applied from the restraint band that restrains the battery laminate from the outside of the end plate to the battery laminate.

It is preferable that the end plate has a configuration in which a plurality of restraint band fixing portions and a plurality of claw hook portions are alternately arranged side by side in the longitudinal direction of the end plate. Here, the longitudinal direction of the end plate is a predetermined direction orthogonal to the stacking direction. Also, the length of the end plate in the longitudinal direction is longer than the length in the width direction.

When the plurality of restraint band fixing portions and the plurality of claw hook portions are arranged alternately in the longitudinal direction of the end plates, the distance between the pair of end plates is widened when assembling the battery module. When the end plate is pulled with a jig as described above, the deflection of the end plate can be suppressed.

In each of FIGS. 5A and 5B, when assembling the battery module, the jig engaged with one of the end plates 20 is pulled in order to widen the distance between the pair of end plates 20. It is a schematic diagram which shows. In FIGS. 5A and 5B, the restraint band 30 is connected to the end plate 20, and the restraint pressure by the restraint band 30 is applied in the direction of the white arrow. Further, in the figure, the jig 200 is temporarily engaged with the end plate 20, and the jig 200 is pulled in the direction of the black arrow.

Here, the direction of the restraining pressure by the restraining band 30 applied near the center of the end plate 20 and the direction of the force applied to the end plate 20 by pulling the jig 200 are opposite to each other.

Therefore, as shown in FIG. 5A, when the claw hooks are arranged only on both ends in the longitudinal direction of the end plate 20, the force applied to the vicinity of the center and the vicinity of both ends of the end plate 20 is applied. The different orientations may cause the end plate 20 to bend.

On the other hand, as shown in FIG. 5B, when a plurality of restraint band fixing portions and claw hook portions are arranged alternately side by side in the longitudinal direction of the end plate 20, the ends are arranged. The force on the end plate 20 becomes more uniform over the entire longitudinal direction of the plate 20. As a result, in the configuration shown in FIG. 5 (b), the deflection of the end plate 20 can be suppressed.

(Restricted band fixing part)
The restraint band fixing portion is a portion for fixing the restraint band. The restraint band fixing portion has a concave shape with respect to other parts of the end plate. As a result, the restraint band is less likely to be displaced from the restraint band fixing portion, and the restraint band can be easily fixed.

The restraint band fixing portion can have any structure capable of fixing the restraint band during assembly and use of the battery module.

For example, the restraint band fixing portion preferably has a rounded shape that is convex toward the opposite side of the battery laminate. When the restraint band fixing portion has such a structure, when the pair of end plates are restrained by the restraint band and the battery laminate is pressurized, the stress that the restraint band receives from the end plates is applied to the restraint band. It can be dispersed over the entire portion in contact with the restraint band fixing portion of the. This improves the durability of the restraint band even when a large tension is applied to the restraint band.

FIG. 6 is a schematic diagram showing an end plate 20c in a battery module according to another embodiment of the present disclosure.

Unlike the end plate 20a shown in FIG. 2, the end plate 20c shown in FIG. 6 has a portion in contact with the restraint band of the restraint band fixing portion 23c having a convex rounded shape toward the opposite side of the battery laminate. ing.

Since the end plate 20c shown in FIG. 6 has such a shape, when the pair of end plates 20c are bound by the restraint band and the battery laminate is pressed, the restraint band becomes the end plate 20c. The stress received from the restraint band can be dispersed over the entire portion in contact with the restraint band fixing portion 23c of the restraint band.

The arrangement and number of restraint band fixing portions are not particularly limited, but may be one or more arranged at both ends in the width direction of the end plate, for example, one end and the other in the width direction of the end plate. The number at each end may be the same or different. Here, the width direction of the end plate is a predetermined direction orthogonal to the stacking direction and the longitudinal direction of the end plate, respectively.

(Claw hook)
The claw hook portion has a concave shape and is a portion to which a jig for pulling the pair of end plates can be temporarily engaged in a direction in which the distance between the pair of end plates is widened.

The claw hook can have any concave shape to which the jig can be temporarily engaged during assembly of the battery module.

The arrangement and number of the claw hooks are not particularly limited, but for example, one or a plurality of claw hooks may be arranged at both ends in the width direction of the end plate, and one end and the other end in the width direction of the end plate may be arranged. The number of parts in each part may be the same or different. Here, the width direction of the end plate is a predetermined direction orthogonal to the stacking direction and the longitudinal direction of the end plate, respectively.

<Restriction band>
The restraint band binds a pair of end plates in the stacking direction and restrains the battery laminate while pressurizing it.

The restraint band may have any shape capable of restraining the battery laminate under pressure via the pair of end plates. For example, the restraint band may be band-shaped.

Examples of the material of the restraint band include metals such as stainless steel, carbon fiber reinforced plastics, and fiber reinforced plastics such as glass fiber reinforced plastics.

<Battery laminate>
The battery laminate has a plurality of building blocks that are laminated to each other.

In the battery laminate, the constituent unit cells may be electrically connected in series or in parallel inside the battery laminate.

Further, the battery laminate may be a battery laminate or a bipolar type battery laminate.

When the battery laminate is a monopolar type battery laminate, the two structural unit cells adjacent to each other in the stacking direction may have a monopolar type configuration sharing a positive electrode current collector layer or a negative electrode current collector layer.

When the battery laminate is a bipolar type battery laminate, the two unit all-solid-state batteries adjacent in the stacking direction share a positive / negative current collector layer used as both a positive electrode and a negative electrode current collector layer. It may be a type configuration.

The battery laminate may be enclosed in the exterior body. The exterior body may be any exterior body used for enclosing the battery laminate as long as it has a shape capable of laminating the battery laminates in the stacking direction.

(Constituent unit cell)
The constituent unit cell may be either an all-solid-state battery or a liquid-based battery. When the constituent unit cell is an all-solid-state battery, the constituent unit cell has a configuration in which a positive electrode current collector, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, and a negative electrode current collector are laminated in this order. Can be. When the constituent unit cell is an all-solid-state battery, those layers generally used in the all-solid-state battery can be used as these layers included in the constituent unit cell.

<Cooling plate>
It is preferred that the battery module of the present disclosure has two or more restraining bands and that the cooling plate is located between the two restraining bands and in the region extending from one end plate to the other end plate.

It is known that the battery laminate generates heat when the battery laminate included in the battery module is charged and discharged. Therefore, it is required to arrange a cooling plate or the like on the battery module to cool the battery laminate.

In the battery module of the present disclosure, when the cooling plate is arranged as described above, the increase in the occupied volume of the battery module due to the arrangement of the cooling plate in the battery module is suppressed by, for example, the thickness of the restraint band. be able to. This makes it possible to suppress a decrease in the volumetric energy density of the battery module.

In the battery module having such a configuration, the end plate has, for example, a shape in which the width of the portion where the restraint band fixing portion is arranged is the same as or larger than the width of the portion where the claw hook portion is arranged. You can do it.

As the material of the cooling plate, any material capable of conducting and / or absorbing the heat generated during charging / discharging of the battery laminate to the outside of the battery module can be used. Specifically, the cooling plate may be a metal plate, for example, a copper plate, an aluminum plate, an iron plate, a stainless steel plate, or the like, but is not limited thereto.

FIG. 7 is a schematic diagram showing a battery module 100d according to still another embodiment of the present disclosure.

In the battery module 100d shown in FIG. 7, in addition to the configuration of the battery module 100a shown in FIG. 1, the cooling plate 40 is arranged between the two restraint bands 30 and in the region extending from one end plate 20d to the other end plate 20d. Has been done.

FIG. 8 is a schematic diagram showing an end plate 20d in a battery module 100d according to still another embodiment of the present disclosure.

Unlike the end plate 20a shown in FIG. 2, the end plate 20d shown in FIG. 8 has a shape in which the width of the portion where the restraint band fixing portion 23d is arranged is larger than the width of the portion where the claw hook portion 25d is arranged. Have. The cooling plate 40 is arranged so as to overlap the region between the two restraint bands 30 and from one end plate 20d to the other end plate 20d, that is, the portion where the claw hook 25d is arranged. As a result, the increase in the occupied volume of the battery module 100d by arranging the cooling plate on the battery module 100d is increased by the width of the portion where the claw hook portion 25d is arranged and the width of the portion where the restraint band fixing portion 23d is arranged. It can be suppressed by the difference between the above and the thickness of the restraint band 30.

10 Battery laminate 20a, 20b, 20c, and 20d End plates 23a, 23b, 23c, and 23d Restraint band fixing parts 25a, 25c, and 25d Claw hooks 30 Restraint band 40 Cooling plates 100a and 100d Battery module 200 Jig

Claims (4)

Battery laminates with multiple building blocks stacked on top of each other,
A pair of end plates facing each other with the battery laminate sandwiched in the stacking direction of the constituent unit cells, and a pair of end plates bound in the stacking direction while pressurizing the battery laminate. Has a restraining band that is restraining,
The pair of the end plates
It has a concave restraint band fixing part that fixes the restraint band, and a concave claw hook part that can temporarily engage a jig for pulling the end plates in a direction that widens the distance between the pair of end plates. And the restraint band fixing portion and the claw hook portion do not overlap.
Battery module. The battery module according to claim 1, wherein the portion of the restraint band fixing portion in contact with the restraint band has a curved shape that is convex toward the opposite side of the battery laminate. The battery module according to claim 1 or 2, wherein the plurality of restraint band fixing portions and the plurality of claw hook portions are arranged alternately side by side in the longitudinal direction of the end plate. It has two or more of the restraint bands, and the cooling plate is arranged in the region between the two restraint bands and from one end plate to the other end plate.
The battery module according to any one of claims 1 to 3.

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