阅读说明：本技术 电池组件以及电池组件的制造方法 (Battery module and method for manufacturing battery module ) 是由 中山圣英 武田泰人 竹井英俊 铃木雄大 于 2018-06-27 设计创作，主要内容包括：本发明提供一种电池组件,其具备：壳体20、以叠层方式收纳于壳体20内的多个电池单元30、焊接于电池单元30的电极接线片31的汇流条40、与汇流条40以及对电池单元30的电压进行测定的测定部连接的电压监视线50,汇流条40在电极接线片31附近保持于壳体20,汇流条40和电压监视线50在电压监视线50的端子部51实现了连接,但并不固定于壳体20。(The present invention provides a battery pack, which is provided with: the battery pack includes a case 20, a plurality of battery cells 30 stacked in the case 20, a bus bar 40 welded to an electrode tab 31 of the battery cells 30, and a voltage monitoring line 50 connected to the bus bar 40 and a measurement unit for measuring the voltage of the battery cells 30, wherein the bus bar 40 is held in the case 20 near the electrode tab 31, and the bus bar 40 and the voltage monitoring line 50 are connected to a terminal portion 51 of the voltage monitoring line 50, but are not fixed to the case 20.)

1. A battery pack is provided with:

a case, a plurality of battery cells housed in the case in a stacked manner, a plurality of bus bars welded to electrode tabs of the battery cells, a measurement unit that measures voltages of the battery cells, and a plurality of voltage monitoring lines connected to the bus bars,

each bus bar is held to the case in the vicinity of the electrode tab,

at least one set of the plurality of bus bars and the plurality of voltage monitoring lines is connected at a terminal portion of the voltage monitoring line, but is not fixed to the housing.

2. The battery module according to claim 1, wherein the plurality of bus bars and the plurality of voltage monitoring wires are each independently connected by at least one connection mechanism selected from rivets, solder, welding, screws, and rivets.

3. The battery module according to claim 1, wherein the plurality of bus bars and the plurality of voltage monitoring lines are respectively formed in one body.

4. A method for manufacturing a battery pack, the battery pack comprising:

a case, a plurality of battery cells housed in the case in a stacked manner, a plurality of bus bars welded to electrode tabs of the battery cells, a measurement unit that measures voltages of the battery cells, and a plurality of voltage monitoring lines connected to the bus bars,

each of the bus bars is held to the housing in the vicinity of the electrode tabs, the method including,

at least one set of the plurality of bus bars and the plurality of voltage monitoring lines is connected to a terminal portion of the voltage monitoring line, but is not fixed to the housing.

Technical Field

The present invention relates to a battery module and a method of manufacturing the battery module.

The present application claims priority based on application No. 2017-124903 filed in japan on 27.6.2017, the contents of which are incorporated herein by reference.

Background

In recent years, a general house has been installed with a battery unit to store electric energy generated by solar panels or the like so as to be usable at night. The battery unit includes a case, and a plurality of battery modules accommodated in the case in a stacked manner.

The battery pack includes a case, a plurality of power storage bodies housed inside the case, a bus bar welded to electrode tabs of the power storage bodies, and a voltage monitoring line connected to the bus bar and a measurement portion that measures a voltage of the power storage bodies. In the battery module, the bus bar and the voltage monitoring wire are screwed and fixed to the case at the terminal portion of the voltage monitoring wire (for example, see patent document 1).

Disclosure of Invention

Technical problem to be solved by the invention

However, in the battery module described in patent document 1, the bus bars may be disconnected when vibration is applied.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a battery module capable of preventing bus bars from being disconnected even if vibration is applied.

Means for solving the problems

[1] A battery pack is provided with: the battery pack includes a case, a plurality of battery cells housed in the case in a stacked manner, a plurality of bus bars welded to electrode tabs of the plurality of battery cells, a measurement unit that measures voltages of the plurality of battery cells, and a plurality of voltage monitoring lines connected to the plurality of bus bars, wherein the bus bars are held in the case near the electrode tabs, and at least one set of the plurality of bus bars and the plurality of voltage monitoring lines is connected to a terminal portion of the voltage monitoring lines, but is not fixed to the case.

[2] The battery module according to [1], wherein the plurality of bus bars and the plurality of voltage monitoring wires are each independently connected by at least one connection mechanism selected from rivets, solder, welding, screws, and rivets.

[3] The battery module according to [1], wherein the plurality of bus bars and the plurality of voltage monitoring lines are respectively formed integrally.

[4] A method for manufacturing a battery module, the battery module comprising: the method includes connecting at least one set of the plurality of bus bars and the plurality of voltage monitoring lines to terminal portions of the voltage monitoring lines, but not fixing the bus bars and the voltage monitoring lines to the case.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to provide a battery module capable of preventing the bus bar from being disconnected even when vibration is applied.

Drawings

Fig. 1A is a front view showing a schematic structure of a first embodiment of a battery pack according to the present invention.

Fig. 1B is a view showing a schematic structure of a first embodiment of a battery module of the present invention, which is an enlarged view of a region α in fig. 1A, and is a sectional view taken along a depth direction of fig. 1A.

Fig. 2 is a sectional view showing a schematic structure of a battery cell of a battery pack according to the present invention.

Fig. 3 is a plan view showing a schematic case of a connection structure between bus bars and voltage monitoring lines in a second embodiment of a battery module according to the present invention.

Fig. 4 is a plan view showing a schematic case of a connection structure between bus bars and voltage monitoring lines in a third embodiment of a battery module according to the present invention.

Fig. 5 is a plan view showing a schematic case of a connection structure between bus bars and voltage monitoring lines in a fourth embodiment of a battery module according to the present invention.

Fig. 6 is a plan view showing a schematic case of a connection structure between bus bars and voltage monitoring lines in a fifth embodiment of a battery pack of the present invention.

Fig. 7 is a plan view showing a schematic case of a connection structure between bus bars and voltage monitoring lines in a sixth embodiment of a battery module according to the present invention.

Detailed Description

An embodiment of the battery module of the present invention will be explained.

It should be noted that this embodiment is specifically described for better understanding of the gist of the present invention, and the present invention is not limited to the embodiment unless otherwise specified.

[ Battery Assembly ]

(1) First embodiment

Fig. 1A is a front view showing a schematic configuration of the battery module of the present embodiment. Fig. 1B is a diagram showing a schematic configuration of the first embodiment of the battery module of the present invention, is an enlarged view of a region α in fig. 1A, and is a sectional view taken along the depth direction of fig. 1A.

The battery pack 10 of the present embodiment includes a case 20, a plurality of battery cells 30 stacked in the case 20, a plurality of bus bars 40 welded to electrode tabs 31 of the battery cells 30, a measurement unit (not shown) for measuring the voltage of each of the battery cells 30, and a plurality of voltage monitoring lines 50 of the bus bars 40.

As shown in fig. 1B, on the front surface (end surface perpendicular to the longitudinal direction of the battery assembly 10) 10a side of the battery assembly 10, the bus bar 40 is held by the case 20 in the vicinity of the electrode tab 31 of the battery cell 30. That is, the bus bar 40 is held by the housing 20 by being inserted into an insertion portion (gap) of the bus bar formed on the housing 20.

The electrode tabs 31 of the battery cells 30 and the bus bars 40 are connected by welding at the welding parts 60.

The bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 1B, the bus bar 40 and the voltage monitoring wire 50 are connected to each other at the terminal portion 51 by a rivet 70 as a connecting means. The rivet 70 is housed in a recess 21 formed in the case 20 so as to be recessed in the depth direction of the battery module 10 on the front surface 10a side of the battery module 10. In this case, a gap is preferably present between the rivet 70 and the recess 21.

In the present embodiment, a plurality of sets of the bus bars 40 and the voltage monitoring lines 50 are provided corresponding to the plurality of battery cells 30, and at least one of the sets may be connected but not fixed to the case 20. From the viewpoint of more reliably preventing the bus bars from being disconnected due to vibration or the like, and from the viewpoint of making the battery assembly 10 easier to manufacture, it is preferable that 1/3 or more of the plurality of sets, more preferably 1/2 or more, further preferably 2/3 or more, and most preferably all of the sets are connected, but not fixed to the case 20. In particular, in the case where the battery cells 30 are connected in series, it is preferable that all of the plurality of groups are connected to the case 20 but not fixed to the case 20.

Here, "fixed" means a state of being joined to the housing 20 even by mechanical joining, welding, adhesion, or the like, and not being detached from the housing 20 even if a certain force is applied. The "fixed" state does not include the bus bar 40 and the voltage monitoring wire 50 simply making contact with the housing 20 in the movable state.

The structure of the battery cell 30 is not particularly limited. For example, as shown in fig. 2, the battery cells 30 are formed in a sheet shape (plate shape). The battery unit 30 includes a power storage body 32, a package 33 housing the power storage body 32, and an electrolyte 34 filled in the package 33.

The storage cell 32 is configured by alternately stacking positive electrode portions 35 and negative electrode portions 36 in the thickness direction of the battery cell 30. The positive electrode portion 35 includes a positive electrode sheet (not shown) and a positive electrode active material layer (not shown) provided on a main surface thereof. Negative electrode portion 36 includes a negative electrode sheet (not shown) and a negative electrode active material layer (not shown) provided on a principal surface thereof.

Separator 37 is disposed between positive electrode 35 and negative electrode 36. That is, the positive electrode portion 35, the separator 37, the negative electrode portion 36, the separator 37, and the positive electrode portion 35 … are stacked in this order to form the power storage body 32.

As the positive electrode sheet, aluminum foil or the like can be used. As the positive electrode active material layer, a lithium metalate compound represented by the general formula "LiMxOy (where M is a metal; and x and y are composition ratios of the metal M to oxygen O)" or the like is used. Examples of the lithium metal oxide compound include: lithium cobaltate (LiCoO)₂) Lithium nickelate (LiNiO)₂) And the like.

As the negative electrode sheet, copper foil or the like can be used. As the negative electrode active material layer, graphite (graphite), silicon oxide, or the like can be used.

The material of the separator 37 is not particularly limited, and examples thereof include: microporous polymer films, nonwoven fabrics, glass fibers, and the like.

The structure of the outer package 33 is not particularly limited. The exterior body 33 has, for example, a first laminated film 38 and a second laminated film 39 formed by laminating a modified PP (polypropylene) layer, an aluminum layer, a nylon layer, and a PET (polyethylene terephthalate) layer from the inner layer side.

The package 33 is formed into a bag shape by welding the edge of the modified PP layer of the first laminated film 38 and the edge of the modified PP layer of the second laminated film 39.

The electrolyte 34 is not particularly limited, and for example, it can be suitably used: known electrolytes, electrolytic solutions, and the like are used for lithium ion secondary batteries. The electrolytic solution may be a mixed solution in which an electrolyte salt is dissolved in an organic solvent.

The battery unit 30 includes a pair of tabs (terminals), not shown. The battery cell 30 may be charged or discharged through a pair of tabs.

The mass of one or more battery cells 30 is several tens kg to 100kg, etc., and is relatively heavy.

In the battery pack 10 of the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the case 20. Therefore, even if vibration is applied to the terminal portion 51 of the voltage monitoring line 50, the bus bar 40 can be prevented from being disconnected.

(2) Second embodiment

Fig. 3 is a schematic plan view showing a connection structure between the bus bar and the voltage monitoring line in the battery module of the present embodiment. In fig. 3, the same components as those shown in fig. 1 are denoted by the same reference numerals, and description thereof is omitted.

In the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 3, the bus bar 40 and the voltage monitoring line 50 are connected by the solder 80 of the connection mechanism at the terminal portion 51 of the voltage monitoring line 50. Further, the connection portion containing the solder 80 is on the front surface 10a side of the battery assembly 10, and is not fixed to the case 20.

According to the battery module of the present embodiment, the same effects as those of the battery module 10 of the first embodiment can be obtained.

(3) Third embodiment

Fig. 4 is a schematic plan view showing a connection structure between the bus bar and the voltage monitoring line in the battery module of the present embodiment. In fig. 4, the same reference numerals are used to designate the same components as those shown in fig. 1, and the description thereof will be omitted.

In the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 4, the bus bar 40 and the voltage monitoring line 50 are connected to each other at the terminal portion 51 by the welding portion 90 of the connection mechanism. Further, the connection portion including the welding portion 90 is on the front surface 10a side of the battery assembly 10, and is not fixed to the case 20.

According to the battery module of this embodiment, the same effects as those of the battery module 10 of the first embodiment can be obtained.

(4) Fourth embodiment

Fig. 5 is a schematic plan view showing a connection structure between the bus bar and the voltage monitoring line in the battery module of the present embodiment. In fig. 5, when the same structure as that shown in fig. 1 is provided, the same reference numerals are used and the description thereof is omitted.

In the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to each other at the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 5, the bus bar 40 and the voltage monitoring line 50 are connected at the terminal portion 51 by a screw 100 as a connection mechanism. The screw 100 is housed in a recess formed in the case 20 so as to be recessed in the depth direction of the battery module 10 on the front surface 10a side of the battery module 10. In this case, a gap is preferably present between the screw 100 and the recess.

According to the battery module of this embodiment, the same effects as those of the battery module 10 of the first embodiment can be obtained.

(5) Fifth embodiment

Fig. 6 is a schematic plan view showing a connection structure between bus bars and voltage monitoring lines of the battery module of the present invention. In fig. 6, when the same structure as that shown in fig. 1 is provided, the same reference numerals are used and the description thereof is omitted.

In the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 6, the bus bar 40 and the voltage monitoring line 50 are connected to each other at the terminal portion 51 by a caulking portion 110 as a connecting means. The caulking portion 110 is provided at an end portion of the bus bar 40 opposite to the portion held by the case 20. The terminal portion 51 of the voltage monitoring line 50 is inserted into the caulking portion 110 and caulked to the caulking portion 110, whereby the bus bar 40 and the voltage monitoring line 50 are connected. The connection portion including the caulking portion 110 is on the front surface 10a side of the battery module 10, but is not fixed to the case 20.

According to the battery module of this embodiment, the same effects as those of the battery module 10 of the first embodiment can be obtained.

(6) Sixth embodiment

Fig. 7 is a schematic plan view showing a connection structure between bus bars and voltage monitoring lines of the battery module of the present invention. In fig. 7, the same reference numerals are used to designate the same components as those shown in fig. 1, and the description thereof will be omitted.

In the present embodiment, the bus bar 40 and the voltage monitoring line 50 are connected to the terminal portion 51 of the voltage monitoring line 50, but are not fixed to the housing 20. More specifically, as shown in fig. 7, the bus bar 40 and the voltage monitoring line 50 are connected by being integrated. The bus bar 40 and the voltage monitoring line 50 are integrally formed by pressing a metal plate or the like. The boundary 45 between the bus bar 40 and the voltage monitoring line 50 is on the front surface 10a side of the battery module 10, but is not fixed to the case 20.

According to the battery module of this embodiment, the same effects as those of the battery module 10 of the first embodiment can be obtained.

[ method for producing Battery Module ]

The battery module is manufactured by a known method except that at least one set of the plurality of bus bars and the plurality of voltage monitoring lines is connected to a terminal portion of the voltage monitoring line, but is not fixed to the case.

According to this method, it is not necessary to fix the bus bar and the voltage monitoring wire to the case, and therefore, not only the battery module can be easily manufactured, but also the battery module that can prevent the bus bar from being disconnected even if vibration is applied can be manufactured as described above, as compared with the conventional method.

[ Note ] of

10 … battery pack

20 … casing

21 … concave part

30 … battery cell

31 … electric connecting piece

32 … accumulator

33 … outer package

34 … electrolyte

35 … Positive electrode part

36 … negative electrode part

37 … baffle

38 … first laminated film

39 … second laminated film

40 … bus bar

50 … voltage monitoring line

51 … terminal part

60 … weld

70 … rivet

80 … solder

90 … weld

100 … screw

110 … riveting part