JP2013143185A - Battery module and battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module which uses a large number of batteries having large electrode film thickness and is capable of suppressing deterioration due to a temperature distribution generated during charging/discharging even when the batteries having large electrode film thickness are arranged in the battery module.SOLUTION: In a battery module 30, batteries 20a having small electrode film thickness are arranged at portions where a temperature distribution generated during charging/discharging of the battery module 30 becomes high, and batteries 20b having large electrode film thickness are arranged at portions where the temperature distribution becomes low.

Description

  The present invention relates to a battery module and a collection battery, and more particularly to a technique for reducing member costs and suppressing deterioration due to temperature.

  In order to satisfy battery performance requirements of high voltage and large capacity, a plurality of single cells are connected as a battery module, and a plurality of battery modules are connected and used as a collection battery.

  Here, in the battery module or the collection battery, the variation of the deterioration rate of the unit cell constituted by the temperature distribution generated inside occurs, and the life of the battery module or the collection battery is determined by rate-determining the unit cell having the greatest deterioration. A known method has been reported for determining the arrangement of the single cells so that the deterioration rates of the single cells arranged in the battery module or the collection battery are equal.

  As a background art in this technical field, there is JP-A-2000-231911 (Patent Document 1). This patent document 1 states that, even when the battery can theoretically be discharged depending on its state, the output may not be taken out if the battery temperature is low, and the tendency is that the battery with the larger storage capacity becomes smaller. By disposing a large battery in the peripheral area where it is easy to cool, it is possible to prevent the output characteristics of the entire battery from deteriorating due to a temperature difference between the batteries ”(see summary).

JP 2000-231911 A

  In recent years, in order to reduce battery member costs, the thickness of electrodes has been increased, and when the electrode film thickness is thick, deterioration is accelerated at high temperatures.

  However, in Patent Document 1, a battery having a larger storage capacity is disposed at a portion where deterioration of the battery constituting the collection battery is expected to be accelerated due to a temperature distribution generated during charging and discharging. If the battery is composed of thick batteries and ranked according to manufacturing variations of the same battery, and a battery with a large storage capacity is placed at a site where deterioration is expected to be accelerated, an electrode film is further added to the high temperature portion where deterioration is expected to be accelerated. Since a thick battery is disposed, deterioration may be further accelerated.

  Therefore, an object of the present invention is to suppress deterioration due to temperature distribution that occurs during charging / discharging even when a battery having a large electrode film thickness is used and a battery having a large electrode film thickness is arranged in a battery module. The object is to provide a battery module and a collecting battery.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  That is, a typical outline of a battery module is a battery module, in which a battery with a thin electrode film thickness is disposed in a part where the temperature distribution generated during charging and discharging of the battery module is high, and an electrode film is provided in a part where the temperature distribution is low. A thick battery is arranged.

  In addition, each battery module is a battery module in which a battery with a thin electrode film thickness is disposed at a part where the temperature distribution generated during charging and discharging is high, and a battery with a thick electrode film is formed at a part where the temperature distribution is low. Is arranged.

  The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, the effect obtained by a typical one is that by increasing the electrode film thickness, the amount of the electrode foil and the separator can be reduced, and the member cost can be reduced. In addition, even when a battery having a thick electrode film is disposed in a battery module, it is possible to suppress deterioration due to temperature distribution that occurs during charging and discharging.

It is a block diagram which shows the structure of the battery module which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the battery used with the battery module which concerns on Embodiment 1 of this invention. It is a figure which shows the deterioration characteristic by the temperature of the battery used for the battery module which concerns on Embodiment 1 of this invention. It is a figure which shows the deterioration characteristic by the temperature of the battery used for the battery module which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the collection battery which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the collection battery which concerns on Embodiment 3 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

(Embodiment 1)
<Configuration of battery module>
The configuration of the battery module according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 is a configuration diagram showing the configuration of the battery module according to Embodiment 1 of the present invention.

  In the present embodiment, the battery module is configured such that deterioration due to temperature distribution that occurs during charging and discharging can be suppressed even when a thick film battery is placed in the battery module.

  In FIG. 1, a battery module 30 is configured such that a battery 20a having a thin electrode film thickness is disposed at the center and a battery 20b having a thick electrode film thickness is disposed at an end thereof. The battery 20b having a large electrode film thickness is a battery having the same capacity.

  Here, the configuration of the battery used in the battery module according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 2 is a configuration diagram showing the configuration of the battery used in the battery module according to Embodiment 1 of the present invention. FIG. 2 (a) shows the configuration of the battery 20a having a thin electrode film thickness, and FIG. The structure of the battery 20b with a thick electrode film thickness is shown.

  In FIG. 2, the battery 20a having a thin electrode film thickness and the battery 20b having a thick electrode film thickness have a configuration in which a plurality of electrode electrodes 41 sandwiched between a positive electrode and a negative electrode are separated by a separator 40. Yes.

  Since the capacity of the battery increases as the electrode film thickness increases, the battery 20a with the thin electrode film thickness shown in FIG. 2 (a) and the electrode film thickness as shown in FIG. In the battery 20b, the number of electrodes is different, and the battery 20b with a thicker electrode film can be configured with a smaller number of separators 40 and electrode foils 41. By using the battery 20b with a thicker electrode film, a member can be obtained. Costs can be reduced.

  In addition, the deterioration of the battery may be promoted when the battery temperature becomes high, and the tendency is that the thicker the electrode film, the more the deterioration is promoted, and the thicker the electrode film is, the more heat is generated during charging / discharging. In this embodiment, as shown in FIG. 1, a battery 20b having a thick electrode film thickness is used. However, the battery 20b having a thick electrode film thickness is arranged in a peripheral part that is easily cooled, and the center part has a film thickness of the electrode film thickness. By disposing the thin battery 20a, it is possible to suppress deterioration of the battery module 30 as a whole due to a temperature difference between the batteries.

<Deterioration characteristics due to battery temperature>
Next, with reference to FIG. 3 and FIG. 4, deterioration characteristics due to temperature of the battery used in the battery module according to Embodiment 1 of the present invention will be described. 3 and 4 are graphs showing deterioration characteristics depending on the temperature of the battery used in the battery module according to Embodiment 1 of the present invention, FIG. 3 is a deterioration characteristic of the battery 20a having a thin electrode film thickness, and FIG. The deterioration characteristic of the battery 20b with a thick electrode film thickness is shown.

  As shown in FIGS. 3 and 4, the deterioration promotion of the battery 20a having a thin electrode film thickness is the same as that of the battery 20b having a thick electrode film thickness under the normal temperature environment, but the electrode film thickness is thick under a high temperature environment. The battery 20b is more accelerated in deterioration than the battery 20a having a thin electrode film thickness.

  Therefore, as in the present embodiment, the battery 20b with a thick electrode film thickness is arranged in the peripheral portion where it is easy to cool, thereby suppressing the deterioration of the battery even when the battery module 20b with a thick electrode film thickness is used. can do.

(Embodiment 2)
In the second embodiment, a plurality of battery modules of the first embodiment are arranged to form a collection battery.

  With reference to FIG. 5, the configuration of the battery according to the second embodiment of the present invention will be described. FIG. 5 is a configuration diagram showing the configuration of the battery pack according to Embodiment 2 of the present invention.

  In FIG. 5, the collection battery 200 includes battery modules 130 to 135 including a battery 120 a having a thin electrode film thickness and a battery 120 b having a thick electrode film thickness.

  In the battery modules 130 to 135, two batteries 120 a having the same capacity and thin battery thickness are arranged on the contact side of each battery module, and three batteries 120 b having the same capacity and thick battery thickness are arranged on the side opposite to the contact surface. Arranged and configured.

  Thus, the battery 120a with a thin electrode film thickness is configured on the contact surface side of the battery module, and the battery 120b with a thick electrode film thickness is configured on the side opposite to the contact surface.

  As the battery temperature rises, the deterioration of the battery may be accelerated, and the tendency is that the thicker the electrode film, the more the deterioration is promoted, and the thicker the battery film, the greater the heat generated during charging / discharging. In this embodiment, by disposing the battery 120b having a thick electrode film thickness in the peripheral portion where it is easy to be cooled, it is possible to suppress the deterioration of the entire collection battery 200 based on the occurrence of a temperature difference in the battery.

  FIG. 5 shows an example in which the battery modules are arranged side by side. However, when the temperature distributions of the batteries are different when they are arranged in the horizontal direction, the electrode film thickness varies depending on the temperature distribution. A battery may be used.

(Embodiment 3)
In the third embodiment, a cooling member is provided on the contact side of the battery module in the second embodiment.

  With reference to FIG. 6, the structure of the battery according to the third embodiment of the present invention will be described. FIG. 6 is a configuration diagram showing a configuration of a battery collection according to Embodiment 3 of the present invention.

  In FIG. 6, the collection battery 300 includes a cooling member 301, and battery modules 230 to 235 including a battery 220 a having a thin electrode film thickness and a battery 220 b having a thick electrode film thickness.

  In each of the battery modules 230 to 235, two batteries 220 b having the same capacity and thick battery thickness are arranged on the contact side of the cooling member 301, and three batteries 220 a having the same capacity and thin battery thickness are arranged on the side opposite to the contact surface. Arranged and configured.

  As described above, the battery 120b having a thick electrode film thickness is configured on the contact side of the cooling member 301, and the battery 120a having a thin electrode film thickness is configured on the side opposite to the contact side of the cooling member 301.

  In the present embodiment, by disposing battery 120b having a large electrode film thickness on the cooling member 301 side that is easily cooled, deterioration of the entire collection battery 200 based on the occurrence of a temperature difference in the battery can be suppressed.

  In the present embodiment, the battery 220b having a thick electrode film thickness is arranged on the contact side of the cooling member 301. However, the battery 220b having a thick electrode film thickness is also arranged in the periphery as in the second embodiment. You may do it. In that case, you may make it change the electrode film thickness of the contact side of a cooling member 301, and a peripheral part.

  FIG. 6 shows an example in which the battery modules are arranged side by side. However, when the temperature distribution of the batteries is different when arranged in the horizontal direction, the electrode film thickness varies depending on the temperature distribution. A battery may be used.

  Alternatively, the cooling member 301 in FIG. 6 may be configured with a flow path for flowing a cooling medium, and a battery near the upstream of the flow path may be a battery 220b having a thick electrode film thickness.

  In addition, this invention is not limited to above-described embodiment, Various modifications are included. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. . Further, a part of the configuration of each embodiment can be added to, deleted from, or replaced with another embodiment.

  The present invention relates to a battery module and a collection battery, and can be widely applied to a battery module, a collection battery, and the like that require reduction in member cost and suppression of deterioration.

  20a, 120a, 220a ... batteries with thin electrode film thickness, 20b, 120b, 220b ... batteries with thick electrode film thickness, 30, 130-135, 230-235 ... battery module, 40 ... separator, 41 ... electrode foil, 301 ... Cooling member.

Claims (6)

A battery module in which a plurality of batteries are arranged side by side,
The battery having a thin electrode film thickness is disposed in a portion where the temperature distribution generated during charging / discharging of the battery module is high, and the battery having a large electrode film thickness is disposed in a portion where the temperature distribution is low. Battery module. The battery module according to claim 1,
The battery module is characterized in that the portion where the temperature distribution is high is a central portion of the battery module. A battery pack including a plurality of battery modules in which a plurality of batteries are arranged side by side,
In each of the battery modules, the battery having a thin electrode film thickness is disposed at a portion where the temperature distribution generated during charging and discharging is high, and the battery having the thick electrode film is disposed at a portion where the temperature distribution is low. A battery pack characterized by that. The current collector battery according to claim 3.
The battery pack is characterized in that the part where the temperature distribution is high is a part close to the contact surface between the battery module and the battery module. The current collector battery according to claim 3.
A cooling member for cooling the battery module;
The battery according to claim 1, wherein the battery having the thick electrode film is disposed at a position near the cooling member of the battery module. 6. The battery according to claim 5, wherein
The cooling member has a flow path through which a cooling medium flows,
A battery having a thicker electrode film disposed closer to the upstream of the flow path.

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