JP2016105360A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device which is arranged to be able to suppress the deposition of a foreign material such as metal powder to an active material while ensuring the permeability of an electrolytic solution into a power-generating element.SOLUTION: A battery 1 (i.e. a power storage device) comprises: a power-generating element 2 having a positive electrode 3, a negative electrode 4 and separators 5 and 6 disposed between the positive electrode 3 and the negative electrode 4. The positive electrode 3 and the negative electrode 4 include, at ends, a positive electrode active material layer-unformed part 33 and a negative electrode active material layer-unformed part 43 respectively. As in sectional view of the power-generating element 2, the positive electrode active material layer-unformed part 33 and the negative electrode active material layer-unformed part 43 are each glued with the corresponding separator 5(6) at least one point; a gap between the positive electrode 3 and the negative electrode 4 adjoins a space outside the power-generating element 2.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power storage element, and particularly to a power storage element having a separator.

  Conventionally, a power storage element having a separator is known (see, for example, Patent Document 1).

  Patent Document 1 discloses a battery (storage element) including a power generation element in which a positive electrode, a first separator, a negative electrode, and a second separator are sequentially stacked and wound around an axis. . The power generation element is accommodated in a case in which an electrolytic solution is injected. In addition, active material layers are formed on both surfaces of the positive electrode and the negative electrode except for one end and the other end, respectively. And in order to suppress foreign materials such as metal powder from entering the power generation element, for example, in FIG. 13 of the document, an adhesive is applied to the side edges of the first separator and the second separator in a cross-sectional view of the power generation element. The first separator and the second separator are arranged so that the side edges of the active material layer are covered by applying the coating and adhering the opposing portions. Specifically, in a cross-sectional view of the power generation element, the end on the positive electrode active material layer non-formed part side (one side) of the first separator is the end part on the one side of the positive electrode active material layer non-formed part and the second separator. The one end of the second separator is bonded to the portion where the positive electrode active material layer is not formed using an adhesive. Further, the negative electrode active material layer unformed part side (the other side) end of the first separator is bonded to the negative electrode active material layer non-formed part and the other end of the second separator with an adhesive, The other end of the two separators is bonded to the negative electrode active material layer non-formed part with an adhesive.

JP2011-216399A

  However, in the battery described in Patent Document 1, since the separator and the active material layer non-formed part are bonded by the adhesive and the separators are also bonded to each other, the inside and the outside of the power generation element are blocked. Has been. Further, the adhesive is difficult to permeate the electrolytic solution. For these reasons, the electrolytic solution is less likely to penetrate into the power generation element. For this reason, while it is possible to suppress foreign materials, such as metal powder, adhering to an active material layer, there exists a problem that the permeability of the electrolyte solution inside a power generation element is not favorable.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to prevent foreign matters such as metal powder while ensuring the permeability of the electrolytic solution into the power generation element. An object of the present invention is to provide a power storage element capable of suppressing adhesion to an active material.

  An electricity storage device according to one aspect of the present invention is disposed between a first electrode plate, a second electrode plate adjacent to the first electrode plate, and the first electrode plate and the second electrode plate. And the first electrode plate and the second electrode plate include an unformed portion in which an active material is not formed at the end, and in the cross-sectional view of the power generating element, The separator is bonded to at least one location, and the space outside the power generation element and the gap between the first electrode plate and the second electrode plate are continuous.

  In the electricity storage device according to one aspect of the present invention, in the cross-sectional view of the power generation element, the non-formed part and the separator are bonded to each other by configuring the non-formed part and the separator to be bonded at least at one place. This makes it difficult for foreign matter such as metal powder mixed into the power storage element during manufacture to enter the power generation element, so that the foreign matter such as metal powder is prevented from entering the first electrode plate and the second electrode plate. It can suppress adhering to. In addition, in the cross-sectional view of the power generation element, the space outside the power generation element and the gap between the first electrode plate and the second electrode plate are configured so that the inside and the outside of the power generation element are blocked. Unlike the case where it is made, the electrolyte solution can permeate into the inside of the power generation element (portion between the separator and the active material) from the gap between the first electrode plate and the second electrode plate. Thereby, the permeability of the electrolytic solution into the power generation element can be ensured. Therefore, in this electrical storage element, it can suppress that foreign materials, such as metal powder, adhere to an active material, ensuring the permeability | transmittance of the electrolyte solution to the inside of an electric power generation element.

  In the electricity storage device according to the above aspect, preferably, at least one of the first electrode plate and the second electrode plate is provided with unformed portions at both ends of the electrode plate, The forming part and the separator are bonded together. If comprised in this way, since an active material can be covered with the separator adhere | attached on both ends, it can further suppress that foreign materials, such as a metal powder, adhere to an active material.

  In the electricity storage device according to the above aspect, the separator is preferably bent, and the first electrode plate or the second electrode plate is disposed on the valley side of the bent separator. If comprised in this way, unlike the case where each surface of a 1st electrode plate (2nd electrode plate) is covered with a separate separator (2 separators), a 1st electrode plate (2nd electrode will be 2nd). Can be covered on both sides. Thereby, it can suppress easily that foreign materials, such as metal powder, adhere to an active material with a simple structure. Moreover, the number of parts can be reduced as compared with the case where the first electrode plate (second electrode plate) is covered with two separators.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that foreign materials, such as a metal powder, adhere to an active material, ensuring the permeability | transmittance of the electrolyte solution to the inside of an electric power generation element as mentioned above.

1 is a cross-sectional view illustrating a battery according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view of a positive electrode, a separator, and a negative electrode taken along line 900-900 in FIG. 1 of the battery according to the first embodiment of the present invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line of the battery by 2nd Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line of the battery by 3rd Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line | wire of the battery by 4th Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line | wire of the battery by the modification of 2nd Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line | wire of the battery by the other modification of 2nd Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line of the battery by the modification of 3rd Embodiment of this invention. It is sectional drawing of the positive electrode, the separator, and negative electrode which followed the 900-900 line of the battery by the modification of 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)

  First, with reference to FIG. 1 and FIG. 2, the structure of the battery 1 by 1st Embodiment of this invention is demonstrated. The battery 1 is an example of the “storage element” in the present invention.

  A battery (for example, a lithium ion battery) 1 according to the first embodiment of the present invention includes a power generation element 2 as shown in FIG. The power generation element 2 is formed by winding a positive electrode 3, a negative electrode 4, and separators 5 and 6 disposed between the positive electrode 3 and the negative electrode 4 around a winding axis 600 extending in the X direction. Is formed. The winding axis 600 is a virtual line that does not actually exist. The battery 1 may have a winding axis such as a plate material, or the winding axis may be removed after the power generation element 2 is completed, and the battery 1 may not have the winding axis. The power generation element 2 is accommodated in the case 8. In addition, a battery lid 9 is attached to the case 8 by laser welding so as to close the opening of the case 8 in a state where an electrolyte solution (not shown) is injected into the case 8. The positive electrode 3 is connected to the positive electrode current collector 10. The positive electrode current collector 10 is connected to the positive electrode terminal 10b through the resin member 10a. The negative electrode 4 is connected to the negative electrode current collector 11. The negative electrode current collector 11 is connected to the negative electrode terminal 11b through the resin member 11a.

  The positive electrode 3 is obtained by forming a positive electrode active material layer 32 on a positive electrode base 31 made of a long strip-shaped aluminum foil or aluminum alloy foil. Further, the positive electrode 3 includes a positive electrode active material layer non-formed portion 33 in which the positive electrode active material layer 32 is not formed along the long direction. The positive electrode active material layer 32 is formed on both surfaces of the positive electrode base material 31 as shown in FIG. Further, the positive electrode active material layer non-formed portions 33 are formed on both sides near the end portion on one side (X2 direction side) of the positive electrode base material 31 in the width direction. In addition, the positive electrode active material layer non-forming portion 33 protrudes (extrudes) outward (X2 direction side) from the end portion on one side of the negative electrode 4. Further, the positive electrode active material layer non-forming portions 33 are formed on both surfaces of the positive electrode 3. Actually, the positive electrode base material 31 (positive electrode active material layer non-formed part 33) further protrudes (extends) in the X2 direction side than the state shown in FIG. 2, and the negative electrode base material 41 (negative electrode active material). The layer non-formed portion 43) further protrudes in the X1 direction side, but is shown in FIG. The positive electrode active material layer unformed portion 33 is an example of the “unformed portion” in the present invention. The positive electrode 3 is an example of the “first electrode plate” in the present invention.

  Further, the positive electrode active material layer non-forming portion 33 is bundled and then held by the positive electrode current collector 10 and connected to the positive electrode terminal 10b (see FIG. 1). The positive electrode active material layer non-formed part 33 and the positive electrode current collector 10 are joined by ultrasonic welding. The positive electrode active material is not particularly limited, and various positive electrode active materials can be used.

  The negative electrode 4 is obtained by forming a negative electrode active material layer 42 on a negative electrode substrate 41 made of a long strip-like copper foil or copper alloy foil. Further, the negative electrode 4 includes a negative electrode active material layer non-formed part 43 in which the negative electrode active material layer 42 is not formed along the long direction. The negative electrode active material layer 42 is formed on both surfaces of the negative electrode base material 41 as shown in FIG. In addition, the negative electrode active material layer non-formed portion 43 is formed on both surfaces near the end on the other side (X1 direction side) of the negative electrode base material 41 in the width direction. Further, the negative electrode active material layer non-formed portion 43 protrudes outward (extrudes) from the other end portion of the positive electrode 3 (X1 direction side). That is, the negative electrode active material layer non-formed part 43 and the positive electrode active material layer non-formed part 33 are formed so as to extend in opposite directions in the X direction. The negative electrode active material layer non-formed portions 43 are formed on both surfaces of the negative electrode 4 in the Y direction. The negative electrode active material layer unformed portion 43 is an example of the “unformed portion” in the present invention. The negative electrode 4 is an example of the “second electrode plate” in the present invention.

  The negative electrode active material layer non-formed part 43 is bundled and then held by the negative electrode current collector 11 and connected to the negative electrode terminal 11b (see FIG. 1). The negative electrode active material layer non-formed part 43 and the negative electrode current collector 11 are joined by ultrasonic welding. The negative electrode active material is not particularly limited, and various negative electrode active materials can be used.

  In the X direction, the width of the negative electrode active material layer 42 is larger than the width of the positive electrode active material layer 32. Further, both end portions of the negative electrode active material layer 42 are configured to extend outward from both end portions of the positive electrode active material layer 32 in the X direction.

  The separator 5 (6) is a long strip member made of resin, and is formed of a porous material having a large number of pores. Specifically, the separator 5 (6) can be formed of PE (polyethylene) or PP (polypropylene). The separator 5 (6) has a function of insulating the positive electrode 3 and the negative electrode 4 and allowing the electrolytic solution to pass therethrough.

  As shown in FIG. 2, the power generation element 2 includes a positive electrode 3, a separator 5, a negative electrode 4, and a separator 6 in order from the winding center (winding axis 600) side (Y2 direction side) in the cross-sectional view. They are sequentially stacked. In the X direction, both end portions of the separator 5 (6) are configured to extend outward from both end portions of the positive electrode active material layer 32 and both end portions of the negative electrode active material layer 42. The cross-sectional view of the power generation element 2 is a cross-sectional view in the direction along the protruding direction of the positive electrode active material layer non-formed part 33 (negative electrode active material layer non-formed part 43) in the power generation element 2, as shown in FIG. The case where the cross section along a 900-900 line is seen is shown, and it is the same also in subsequent embodiment.

  Here, in the first embodiment, the separator 5 is configured not to be bonded to the separator 6. Moreover, the edge part of the positive electrode active material layer non-formation part side (X2 direction side) of the separator 5 is adhere | attached with the surface of the Y1 direction side of the positive electrode active material layer non-formation part 33 with the double-sided tape 7 mentioned later. Further, the end of the separator 5 on the negative electrode active material non-formed part side (X1 direction side) is bonded to the surface on the Y2 direction side of the negative electrode active material layer non-formed part 43 by the double-sided tape 7. Further, the end of the separator 6 on the positive electrode active material layer non-formation portion side (X2 direction side) is bonded to the surface of the positive electrode active material layer non-formation portion 33 on the Y2 direction side by a double-sided tape 7. Further, the end of the separator 6 on the negative electrode active material non-formation portion side (X1 direction side) is bonded to the surface of the negative electrode active material layer non-formation portion 43 on the Y1 direction side by a double-sided tape 7.

  That is, in the cross-sectional view of the power generation element 2, the positive electrode active material layer unformed portion 33 is bonded to each of the separator 5 and the separator 6 in the X2 direction, while the positive electrode base material 31 is separated from the separators 5 and 6 in the X1 direction. Therefore, the X1 side of the positive electrode 3 is open to the outside of the power generation element 2. Further, in the cross-sectional view of the power generating element 2, in the X1 direction, the negative electrode active material layer unformed portion 43 is bonded to each of the separator 5 and the separator 6, while in the X2 direction, the negative electrode base material 41 is separated from the separators 5 and 6. Therefore, the X2 side of the negative electrode 4 is open to the outside of the power generation element 2. Thereby, the space outside the power generation element 2 and the gap between the positive electrode 3 and the negative electrode 4 are continuous.

  In other words, the end portion 32d of the positive electrode active material layer 32 opposite to the positive electrode active material layer non-formation portion 33 (X1 direction side) is open (connected to the region 20 where the electrolytic solution is present). Further, the end 42d of the negative electrode active material layer 42 opposite to the negative electrode active material layer non-formed portion 43 (X2 direction side) 42d is open.

  Further, a portion where the surface on the Y1 direction side of the separator 5 and the positive electrode active material layer unformed portion 33 is bonded, and a portion where the surface on the Y2 direction side of the separator 6 and the positive electrode active material layer unformed portion 33 is bonded. Is a substantially corresponding position (overlapping in the Y direction) on the X2 direction side.

  Further, a portion where the surface on the Y2 direction side of the separator 5 and the negative electrode active material layer unformed portion 43 is bonded, and a portion where the surface on the Y1 direction side of the separator 6 and the negative electrode active material layer unformed portion 43 is bonded. Is a substantially corresponding position (overlapping in the Y direction) on the X1 direction side.

  In the first embodiment, the double-sided tape 7 in the X2 direction is not in contact with the positive electrode active material layer 32 (at a predetermined interval from the positive electrode active material layer 32). The positive electrode active material layer non-formed part 33 and the separator 5 (6) are adhered to each other. The double-sided tape 7 in the X1 direction is attached to the surface of the negative electrode active material layer non-formed part 43 so as not to contact the negative electrode active material layer 42 (with a predetermined interval from the negative electrode active material layer 42). The material layer non-formed part 43 and the separator 5 (6) are bonded. With such a configuration, it is possible to prevent the double-sided tape 7 from coming into contact with the positive electrode active material layer 32 or the negative electrode active material layer 42 and causing an adverse effect such as peeling of the active material. Moreover, the double-sided tape 7 is affixed at a position spaced apart from the end of the separator 5 (6) by a predetermined distance in the X direction.

  Further, by bonding the positive electrode active material layer non-formed part 33 (negative electrode active material layer non-formed part 43) and each of the separators 5 and 6 with the double-sided tape 7, the following advantages are obtained. For example, when the positive electrode active material layer non-formed part 33 (negative electrode active material layer non-formed part 43) and each of the separators 5 and 6 are welded (adhered) by heat welding, if the temperature of the heat welding is too high, the separator If 5 and 6 are damaged or the temperature of heat welding is too low, welding between the positive electrode active material layer non-formed part 33 (negative electrode active material layer non-formed part 43) and each of the separators 5 and 6 becomes insufficient. Therefore, it is necessary to finely adjust the temperature at the time of welding. On the other hand, in the configuration using the double-sided tape 7, there is no need to finely adjust the temperature at the time of bonding. ) And each of the separators 5 and 6 can be bonded.

  Moreover, the double-sided tape 7 is made of a material that does not react with the electrolytic solution or hardly reacts. The double-sided tape 7 is made of a material that allows the separator 5 (6) to easily adhere to the positive electrode active material layer non-formed part 33 and the negative electrode active material layer non-formed part 43. Specifically, as the double-sided tape 7, it is possible to use a tape having PPS (Polyphenylene sulfide) as a base material and acrylic glue on both sides.

  In the first embodiment, the following effects can be obtained.

  In the first embodiment, as described above, in the cross-sectional view of the power generation element 2, the positive electrode active material layer non-formed part 33 and each of the separators 5 and 6 are bonded to each other in the X2 direction side, and the negative electrode active material is bonded to the X1 direction side. The material layer non-formed part 43 is bonded to each of the separators 5 and 6. Thereby, the positive electrode active material layer non-formed part 33 (negative electrode active material layer non-formed part 43) and the parts where the separators 5 and 6 are bonded to each other, such as metal powder mixed in the battery 1 at the time of manufacture or the like Since it is possible to make it difficult for foreign matter to enter the power generation element 2, it is possible to prevent foreign matter such as metal powder from adhering to the positive electrode 3 and the negative electrode 4. In addition, in the cross-sectional view of the power generation element 2, the space outside the power generation element 2 and the gap between the positive electrode 3 and the negative electrode 4 are configured to be continuous. Thereby, for example, each of the separators 5 and 6 is bonded to the positive electrode 3 (negative electrode 4) by an adhesive, and the inside of the power generation element 2 and the region 20 where the electrolytic solution is disposed are blocked. The electrolytic solution can penetrate into the space between the positive electrode 3 and the negative electrode 4. Thereby, the permeability of the electrolytic solution into the power generation element 2 can be ensured. Therefore, in the battery 1, it is possible to prevent foreign matters such as metal powder from adhering to the active material while ensuring the permeability of the electrolytic solution into the power generation element 2. As a result, in the battery 1, it is possible to suppress the occurrence of problems such as an internal short circuit due to foreign matters such as metal powder while ensuring the permeability of the electrolytic solution into the power generation element 2.

(Second Embodiment)
Next, with reference to FIG. 1 and FIG. 3, the structure of the battery 100 by 2nd Embodiment of this invention is demonstrated. The battery 100 is an example of the “storage element” in the present invention.

  In the second embodiment, the positive electrode active material layer non-formed part 33 is formed on one side (X2 direction side) of the positive electrode base material 31, and the negative electrode active material is formed on the other side (X1 direction side) of the negative electrode base material 41. Unlike the first embodiment in which the layer non-formed part 43 is formed, the positive electrode active material layer non-formed part 33 is formed on both sides (X1 and X2 direction side) of the positive electrode base material 31 and the negative electrode base material 41 A battery 100 in which negative electrode active material layer non-formed portions 43 are formed on both sides of the battery will be described. Note that in the second embodiment, the same reference numerals are used for the same configurations as in the first embodiment, and description thereof is omitted.

  As shown in FIG. 3, in the battery 100 according to the second embodiment, the positive electrode active material layer unformed portion 33 of the positive electrode 103 is formed in the vicinity of both end portions in the X direction of the positive electrode base material 31. Specifically, the positive electrode active material layer non-formed part 33 includes a first positive electrode active material layer non-formed part 33a on the X2 direction side and a second positive electrode active material layer non-formed part 33b on the X1 direction side. The first positive electrode active material layer unformed portion 33a on the X2 direction side is longer than the second positive electrode active material layer unformed portion 33b on the X1 direction side. Further, the first positive electrode active material layer non-formed part 33a is joined to the positive electrode current collector 10 by ultrasonic welding. The second positive electrode active material layer non-formed part 33b functions as an attachable part to which the separator 5 (6) can be attached without being bonded to the positive electrode current collector 10. Further, the first positive electrode active material layer non-formed part 33 a (second positive electrode active material layer non-formed part 33 b) is formed on both surfaces of the positive electrode 103 in the Y direction. The positive electrode 103 is an example of the “first electrode plate” in the present invention. The first positive electrode active material layer non-formed part 33a and the second positive electrode active material layer non-formed part 33b are examples of the “unformed part” of the present invention.

  The negative electrode active material layer unformed portion 43 of the negative electrode 104 is formed in the vicinity of both end portions in the X direction of the negative electrode base material 41. Specifically, the negative electrode active material layer non-formed part 43 includes a first negative electrode active material layer non-formed part 43a on the X1 direction side and a second negative electrode active material layer non-formed part 43b on the X2 direction side. The first negative electrode active material layer non-formed part 43a on the X1 direction side is longer than the second negative electrode active material layer non-formed part 43b on the X2 direction side. Further, the first negative electrode active material layer non-formed portion 43a is joined to the negative electrode current collector 11 by ultrasonic welding. The second negative electrode active material layer non-formed part 43b functions as an attachable part to which the separator 5 (6) can be attached without being bonded to the negative electrode current collector 11. The first negative electrode active material layer non-formed part 43 a (second negative electrode active material layer non-formed part 43 b) is formed on both surfaces of the negative electrode 104 in the Y direction. The negative electrode 104 is an example of the “second electrode plate” in the present invention. The first negative electrode active material layer non-formed part 43a and the second negative electrode active material layer non-formed part 43b are examples of the “unformed part” of the present invention.

  The separators 5 and 6 are disposed between the positive electrode 103 and the negative electrode 104, respectively. Specifically, the positive electrode 103, the separator 5, the negative electrode 104, and the separator 6 are sequentially laminated in order from the winding center side (Y2 direction side). Further, the separators 5 and 6 are configured to protrude in the X2 direction side from the second negative electrode active material layer non-formed portion 43b. Further, the separators 5 and 6 are configured to protrude to the X1 direction side from the second positive electrode active material layer non-forming portion 33b. Thereby, it can suppress reliably that the positive electrode base material 31 and the negative electrode base material 41 contact.

  Here, in the second embodiment, the end portion on the X2 direction side of the separator 5 is bonded to the surface on the Y2 direction side of the second negative electrode active material layer unformed portion 43b by the double-sided tape 7. Further, the end portion on the X1 direction side of the separator 5 is bonded to the surface on the Y1 direction side of the second positive electrode active material layer non-formed portion 33b by the double-sided tape 7. In addition, the end portion on the X1 direction side of the separator 6 is bonded to the surface on the Y2 direction side of the second positive electrode active material layer unformed portion 33b by the double-sided tape 7. Further, the end portion on the X2 direction side of the separator 6 is bonded to the surface on the Y1 direction side of the second negative electrode active material layer non-formed portion 43b by the double-sided tape 7.

  That is, in the cross-sectional view of the power generating element 2, in the X1 direction, both surfaces of the second positive electrode active material layer unformed portion 33b are bonded to each of the separators 5 and 6, while in the X2 direction, the first positive electrode active material layer Since the unformed portion 33 a is not bonded to each of the separators 5 and 6, the X2 side of the positive electrode 3 is open to the outside of the power generation element 2. In the negative electrode 104, both surfaces of the second negative electrode active material layer non-formed part 43b are bonded to each of the separators 5 and 6 in the X2 direction, while the first negative electrode active material layer non-formed part 43a in the X1 direction. Is not bonded to each of the separators 5 and 6, the X1 side of the negative electrode 4 is open to the outside of the power generation element 2. Thereby, the space outside the power generation element 2 and the gap between the positive electrode 103 and the negative electrode 104 are continuous. Specifically, in a cross-sectional view of the power generation element 2, the first positive electrode active material layer non-formed part 33 a (second positive electrode active material layer non-formed part 33 b) and the first negative electrode active material layer non-formed part 43 a (second negative electrode active part) The material layer non-formed portion 43b) is adhered at four locations among the portions (8 locations) that can contact the separator 5 (6), and between the space outside the power generation element 2 and the positive electrode 103 and the negative electrode 104. The gap is continuous.

  In other words, since the separators 5 and 6 are not bonded to the first positive electrode active material layer non-formed part 33a on the X2 direction side, the positive electrode active material on the first positive electrode active material layer non-formed part 33a side (X2 direction side) The end 32c of the layer 32 is open (connected to the region 20 where the electrolytic solution is present).

  Further, since the separators 5 and 6 are not bonded to the first negative electrode active material layer non-formed part 43a on the X1 direction side, the negative electrode active material layer on the first negative electrode active material layer non-formed part 43a side (X1 direction side) The end part 42c of 42 is open | released (it connects with the area | region 20 in which electrolyte solution exists).

  The portions where the separators 5 and 6 are bonded to the surface of the second negative electrode active material layer non-formed portion 43b are substantially corresponding positions (overlapping in the Y direction) on the X2 direction side.

  Further, the portions where the separators 5 and 6 are bonded to the surface of the second positive electrode active material layer non-formed portion 33b are substantially corresponding positions (overlapping in the Y direction) on the X1 direction side.

  In addition, the other structure of 2nd Embodiment is the same as that of the said 1st Embodiment.

  In the second embodiment, the following effects can be obtained.

  In the second embodiment, as described above, the space outside the power generation element 2 and the gap between the positive electrode 103 and the negative electrode 104 are continuous in the cross-sectional view of the power generation element 2. Thereby, like the said 1st Embodiment, it can suppress that foreign materials, such as a metal powder, adhere to an active material, ensuring the permeability | transmittance of the electrolyte solution to the inside of the electric power generation element 2. FIG.

  Moreover, in 2nd Embodiment, the 2nd positive electrode active material layer non-formation part 33b of the edge part by the side of X1 is adhere | attached with the separator 6 (5). Further, the second negative electrode active material layer non-formed portion 43b at the end portion on the X2 direction side is bonded to the separator 5 (6). If comprised in this way, electrolyte solution from the clearance gap between the positive electrode 103 and the negative electrode 104, covering the negative electrode active material layer 42 and the positive electrode active material layer 32 from the X2 direction and the X1 direction by the separator 5 (6), respectively. Can penetrate into the power generation element 2. Thereby, it can further suppress that foreign materials, such as metal powder, adhere to the positive electrode active material layer 32 and the negative electrode active material layer 42.

  The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

(Third embodiment)
Next, with reference to FIG. 1 and FIG. 4, the structure of the battery 200 by 3rd Embodiment of this invention is demonstrated. The battery 200 is an example of the “storage element” in the present invention.

  In the third embodiment, unlike the first embodiment in which two separators 5 and 6 are provided, a battery 200 in which a bent separator 205 is provided will be described. Note that, in the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 4, in the battery 200 according to the third embodiment, the separator 205 is disposed between the positive electrode 3 and the negative electrode 4.

  The separator 205 is bent on the X1 direction side and is bent substantially in half (in a substantially U-shaped cross-sectional shape). Specifically, the separator 205 includes flat portions 205a and 205b extending in the X direction and a connecting portion 205c extending in the Y direction so as to connect the flat portions 205a and 205b. In the X direction, the flat portions 205a and 205b have substantially the same width. Further, the end portion of the flat portion 205a and the end portion of the flat portion 205b are disposed at substantially the same position (substantially aligned) on the X2 direction side. The positive electrode 3 is disposed on the valley side (inner surface side) of the bent separator 205.

  In other words, the positive electrode 3 is sandwiched with the separator 205 covering the X1 direction side of the positive electrode 3 (positive electrode active material layer 32). More specifically, the separator 205 wraps around from the one surface (the Y1 side surface) of the positive electrode 3 to the end portion (X1 direction side) opposite to the end portion where the positive electrode active material layer non-formed portion 33 is provided. It extends to the other surface (surface on the Y2 direction side) and covers the positive electrode active material layer 32.

  Further, the end portion on the X2 direction side of the flat portion 205a is bonded to the surface on the Y1 direction side of the positive electrode active material layer unformed portion 33 with the double-sided tape 7. Further, the end portion on the X2 direction side of the flat portion 205b is bonded to the surface on the Y2 direction side of the positive electrode active material layer unformed portion 33. The negative electrode 4 is not bonded to the separator 205 and opens to the outside of the power generation element 2 in the X1 direction and the X2 direction. Thereby, in the cross-sectional view of the power generation element 2, the positive electrode active material layer non-formed part 33 and the separator 205 are bonded to each other (two places) so that the space outside the power generation element 2 and the positive electrode 3 and the negative electrode The gap between 4 is continuous.

  In other words, since the positive electrode 3 is covered with the separator 205 and the negative electrode 4 is not covered with the separator, the end portions 42d on the X1 direction side and the X2 direction side of the negative electrode active material layer 42 are opened (electrolytic solution) Is connected to the region 20 where the

  The remaining configuration of the third embodiment is similar to that of the aforementioned first embodiment.

  In the third embodiment, the following effects can be obtained.

  In the third embodiment, as described above, in the cross-sectional view of the power generation element 2, the space outside the power generation element 2 and the gap between the positive electrode 3 and the negative electrode 4 are configured to be continuous. Thereby, like the said 1st Embodiment, it can suppress that foreign materials, such as a metal powder, adhere to an active material, ensuring the permeability | transmittance of the electrolyte solution to the inside of the electric power generation element 2. FIG.

  In the third embodiment, the positive electrode 3 is arranged on the valley side of the folded separator 205. With this configuration, the positive electrode active material layer 32 can be easily covered with the separator 205 with a simple configuration. Thereby, unlike the case where both surfaces of the positive electrode 3 are covered with separate separators (two separators), both surfaces of the positive electrode 3 can be covered with one separator 205. As a result, it is possible to easily suppress foreign matters such as metal powder from adhering to the positive electrode active material layer 32 with a simple configuration. Moreover, compared with the case where the positive electrode 3 is covered with two separators, the number of parts can be reduced.

  The remaining effects of the third embodiment are similar to those of the aforementioned first embodiment.

(Fourth embodiment)
Next, with reference to FIG. 1 and FIG. 5, the structure of the battery 300 by 4th Embodiment of this invention is demonstrated. The battery 300 is an example of the “storage element” in the present invention.

  In the fourth embodiment, the first positive electrode active material layer non-formed part 33a and the second positive electrode active material layer non-formed part 33b on both sides of the positive electrode base material 31 (the first negative electrode active material layer not formed on both sides of the negative electrode base material 41). Unlike the second embodiment in which the formation portion 43a and the second negative electrode active material layer non-formation portion 43b) are provided, and the two separators 5 and 6 are provided, the first positive electrode active material layer is formed on both sides of the positive electrode substrate 31. The non-formed part 33a and the second positive electrode active material layer non-formed part 33b (the first negative electrode active material layer non-formed part 43a and the second negative electrode active material layer non-formed part 43b on both sides of the negative electrode base material 41) are provided. The battery 300 provided with the separators 105 to 108 will be described. Note that in the fourth embodiment, identical symbols are assigned to configurations similar to those in the second embodiment and descriptions are omitted.

  The separators 105 to 108 are disposed between the positive electrode 103 and the negative electrode 104, respectively. Specifically, the positive electrode 103, the separator 105, the separator 107, the negative electrode 104, the separator 108, and the separator 106 are sequentially laminated in order from the winding center side (Y2 direction side).

  In addition, the separators 105 to 108 are configured to protrude in the X2 direction side from the second negative electrode active material layer non-formed portion 43b. In addition, the separators 105 to 108 are configured to protrude to the X1 direction side from the second positive electrode active material layer non-forming portion 33b. Thereby, it can suppress reliably that the positive electrode base material 31 and the negative electrode base material 41 contact.

  Here, in 4th Embodiment, the separator 105 is comprised so that it may not adhere | attach with the other separators 106-108. Similarly, the separators 106 to 108 are also configured so as not to be bonded to other separators. Further, the end portion on the X2 direction side of the separator 105 is bonded to the surface on the Y1 direction side of the first positive electrode active material layer unformed portion 33a by the double-sided tape 7. Further, both end portions in the X direction of the separator 107 are respectively bonded to the surface on the Y2 direction side of the first negative electrode active material layer unformed portion 43a and the second negative electrode active material layer unformed portion 43b by the double-sided tape 7. . Further, both end portions in the X direction of the separator 106 are respectively bonded to the surface on the Y2 direction side of the first positive electrode active material layer non-formed portion 33a and the second positive electrode active material layer non-formed portion 33b by the double-sided tape 7. . Further, the end portion on the X1 direction side of the separator 108 is bonded to the surface on the Y1 direction side of the first negative electrode active material layer non-formed portion 43a by the double-sided tape 7.

  That is, in the cross-sectional view of the power generation element 2, in the X1 direction, the surface of the second positive electrode active material layer unformed portion 33b on the Y1 direction side and the separator 105 are not bonded, and the X1 side of the positive electrode 103 is 2 is open to the outside. Further, in the cross-sectional view of the power generation element 2, in the X2 direction, the surface on the Y1 direction side of the second negative electrode active material layer non-formed portion 43b and the separator 108 are not bonded, and the X2 side of the negative electrode 104 is 2 is open to the outside. Thereby, the space outside the power generation element 2 and the gap between the positive electrode 103 and the negative electrode 104 are continuous. Further, in a cross-sectional view of the power generating element 2, the first positive electrode active material layer non-formed part 33a (second positive electrode active material layer non-formed part 33b) and the first negative electrode active material layer non-formed part 43a (second negative electrode active material layer) The non-formed part 43b) is adhered at six places among the parts (eight places) that can contact the separators 105 to 108, and the space between the outside of the power generation element 2 and the gap between the positive electrode 103 and the negative electrode 104 Is continuous.

  In other words, the separator 105 is not bonded to the second positive electrode active material layer non-formed part 33b on the X1 direction side, so that the positive electrode active material layer 32 on the second positive electrode active material layer non-formed part 33b side (X1 direction side). Is open (connected to the region 20 where the electrolyte is present). Further, since the separator 108 is not bonded to the second negative electrode active material layer non-formed part 43b on the X2 direction side, the negative electrode active material layer 42 on the second negative electrode active material layer non-formed part 43b side (X2 direction side) The end 421d is open (connected to the region 20 where the electrolyte is present).

  Further, the Y1 direction surface of the separator 105 and the first positive electrode active material layer unformed portion 33a is bonded to the Y2 direction surface of the separator 106 and the first positive electrode active material layer unformed portion 33a. The portion where the separator 107 and the surface on the Y2 direction side of the second negative electrode active material layer non-formed portion 43b are bonded is a substantially corresponding (overlapping) position in the X2 direction.

  Also, the Y2 direction side surface of the separator 106 and the second positive electrode active material layer unformed portion 33b is bonded to the Y2 direction side surface of the separator 107 and the first negative electrode active material layer unformed portion 43a. The portion where the surface of the separator 108 and the surface of the first negative electrode active material layer non-formed portion 43a on the Y1 direction side is bonded is a substantially corresponding (overlapping) position in the X1 direction.

  The remaining configuration of the fourth embodiment is similar to that of the aforementioned second embodiment.

  In the fourth embodiment, the following effects can be obtained.

  In the fourth embodiment, as described above, the space outside the power generation element 2 and the gap between the positive electrode 103 and the negative electrode 104 are continuous in a cross-sectional view of the power generation element 2. As a result, as in the second embodiment, foreign matters such as metal powder adhere to the positive electrode active material layer 32 and the negative electrode active material layer 42 while ensuring the permeability of the electrolytic solution into the power generation element 2. Can be suppressed.

  In the fourth embodiment, the first positive electrode active material layer non-formed part 33 a is bonded to the separator 105 (106), and the second positive electrode active material layer non-formed part 33 b is bonded to the separator 106. Further, the first negative electrode active material layer non-formed part 43 a is bonded to the separator 107 (108), and the second negative electrode active material layer non-formed part 43 b is bonded to the separator 107. Thereby, like the said 2nd Embodiment, it can further suppress that foreign materials, such as a metal powder, adhere to the positive electrode active material layer 32 and the negative electrode active material layer 42. FIG.

  The remaining effects of the fourth embodiment are similar to those of the aforementioned second embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first to fourth embodiments, the present invention is applied to a wound type battery (storage element), but the present invention is not limited to this. The present invention can also be applied to a stacked battery.

  Moreover, in the said 1st Embodiment, although both surfaces of the positive electrode active material layer non-formation part were adhere | attached with the separator, this invention is not limited to this. Only one side of the positive electrode active material layer-unformed portion may be bonded to the separator. Moreover, in the said 1st Embodiment, although both surfaces of the negative electrode active material layer non-formation part were adhere | attached with the separator, this invention is not limited to this. In the present invention, only one surface of the negative electrode active material layer unformed portion may be bonded to the separator.

  In the second embodiment, the positive electrode active material layer non-formed part (negative electrode active material layer non-formed part) and the separator can contact with each other (eight parts) in an example where four parts are adhered. Although shown, the present invention is not limited to this. In this invention, it adhere | attaches in arbitrary 1-3 places and 5-7 places among the parts (8 places) which a positive electrode active material layer non-formation part (negative electrode active material layer non-formation part) and a separator can contact. (At least one location may not be adhered).

  Moreover, in the said 2nd Embodiment, although both the positive electrode active material layer non-formation part and the negative electrode active material layer non-formation part were adhere | attached with the separator, this invention is not limited to this. In the present invention, as shown in FIGS. 6 and 7, only the positive electrode active material layer unformed portion may be bonded to the separator. At this time, as shown in FIG. 6, the positive electrode active material layer non-formed part and the separator may be contacted at four locations, or the positive electrode active material layer non-formed as shown in FIG. 7. You may adhere | attach at two places among the parts which a part and a separator can contact. Moreover, you may adhere | attach only a negative electrode active material layer non-formation part with a separator.

  In the third embodiment, one separator 205 bent in a substantially U shape is provided, but the present invention is not limited to this. In the present invention, two separators 205 and 206 may be provided as shown in FIG.

  Moreover, in the said 3rd Embodiment, although the example in which the positive electrode active material layer non-formation part and the separator are in contact with each other (two places) has been shown, the present invention is based on this. Not limited. In this invention, you may adhere | attach at one place among the parts (two places) which a positive electrode active material layer non-formation part and a separator can contact. Moreover, in the said 4th Embodiment, the positive electrode active material layer non-formation part (negative electrode active material layer non-formation part) and the example which adhere | attached at six places among the parts (8 places) which can contact a separator Although shown, the present invention is not limited to this. In the present invention, the positive electrode active material layer non-formed part (negative electrode active material layer non-formed part) and the part (8 places) where the separator can come into contact at any one to 5 places, 7 places and 8 places. It may be adhered. Specifically, as in the modification of the third embodiment shown in FIG. 8 and the modification of the fourth embodiment shown in FIG. 9, the positive electrode active material layer (negative electrode active material layer) is completely formed by the separator. It may be covered with. In this case, although the positive electrode active material layer (negative electrode active material layer) is covered with the separator, the separators are not adhered to each other, so that the electrolyte solution that has entered the gap between the separators penetrates the separator and the positive electrode active material. The layer (negative electrode active material layer) can be reached. Thereby, it can suppress reliably that foreign materials, such as metal powder, adhere to an active material, ensuring the permeability | transmittance of the electrolyte solution to the inside of an electric power generation element.

  In the first and third embodiments, the example in which the positive electrode active material layer non-formed part (negative electrode active material layer non-formed part) is formed only in the vicinity of one end in the X direction has been described. Is not limited to this. In the present invention, the positive electrode active material layer non-formed part (negative electrode active material layer non-formed part) may be formed in the vicinity of both ends in the X direction.

  Moreover, in the said 1st-4th embodiment, although this invention was applied to the lithium ion battery (electric storage element), this invention is not limited to this. The present invention may be applied to non-aqueous electrolyte batteries other than lithium ion batteries, and may be applied to aqueous electrolyte batteries such as nickel metal hydride batteries.

  Moreover, in the said 1st-4th embodiment, a separator, a positive electrode active material layer non-formation part (non-formation part), and a negative electrode active material layer non-formation part (non-formation part) are PPS tape (double-sided tape). Although an example of bonding is shown, the present invention is not limited to this. In the present invention, a double-sided tape other than the PPS tape may be used as long as the material does not react with the electrolytic solution or is difficult to react.

1, 100, 200, 300 Battery (electric storage element)
3, 103 Positive electrode (first electrode plate)
4, 104 Negative electrode (second electrode plate)
5, 6, 105 to 108, 205, 206 Separator 32 Positive electrode active material layer (active material)
33, 33a, 33b Positive electrode active material layer non-formed part (unformed part)
42 Negative electrode active material layer (active material)
43, 43a, 43b Negative electrode active material layer unformed part (unformed part)

Claims (3)

A power generation element having a first electrode plate, a second electrode plate adjacent to the first electrode plate, and a separator disposed between the first electrode plate and the second electrode plate. Prepared,
The first electrode plate and the second electrode plate include an unformed portion where an active material is not formed at an end portion,
In the cross-sectional view of the power generation element, the unformed portion and the separator are bonded at least at one place, and the space outside the power generation element, and between the first electrode plate and the second electrode plate A power storage element having a continuous gap. At least one of the first electrode plate and the second electrode plate is provided with the unformed portions at both ends of the electrode plate,
The electrical storage element according to claim 1, wherein the unformed portions at both ends and the separator are bonded. The separator is bent;
The electrical storage element according to claim 1, wherein the first electrode plate or the second electrode plate is arranged on a valley side of the folded separator.

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