JP2015026522A - Electrode housing separator and power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode housing separator capable of improving immunity to thermal shrinkage while firmly fixing the separator in the state where electrodes are housed inside, and a power storage device.SOLUTION: An electrode housing bag-shaped separator 10 comprises a pair of separator sheets 29 which oppose each other, and a positive electrode sheet 13 is held between the pair of separator sheets 29. In each separator sheet 29, an opposite surface 29c that is a surface at a side opposing the positive electrode sheet 13 is disposed along an upper side 29a and a lower side 29b, and includes a fusion part 33 which is fused with the opposite separator sheet 29. The fusion part 33 is not coated with ceramics. The opposite surface 29c excluding the fusion part 33 and on an entire non-opposite surface 29d at a side opposite to the opposite surface 29c, is coated with ceramics, on the other hand.

Description

  The present invention relates to an electrode storage separator in which an electrode is stored and a power storage device.

  As is well known, rechargeable secondary batteries can be used repeatedly, and are therefore widely used in various devices and apparatuses. In the field of vehicles, the use of fossil fuels (restriction of carbon dioxide emissions) is required. Therefore, vehicles that use this type of secondary battery as a motor power source, so-called hybrid vehicles and EV vehicles (electric vehicle vehicles). ) And so on. In such a secondary battery, charging and discharging with a large current and an increase in battery capacity are required. For example, lithium ion secondary batteries are mass-produced as products.

  As this type of secondary battery, for example, a secondary battery having a laminated structure in which a positive electrode sheet, a negative electrode sheet, and a separator that insulates them are alternately stacked to form an electrode assembly is well known. However, since the laminated structure undergoes a manufacturing process in which the positive electrode sheet, the negative electrode sheet, and the separator are sequentially stacked, the number of stacking processes increases. Therefore, there are problems that the tact time of production is long and the productivity is not good. In view of this, for example, a technique has been devised in which the positive electrode sheet is stored in the bag-shaped separator in advance, thereby reducing the number of the above-described stacking steps and improving battery productivity (see Patent Document 1 and the like). Patent Document 2 describes that a ceramic coated portion and an uncoated portion not coated with ceramic are provided on both front and back surfaces of a resin layer, and a separator is welded at the uncoated portion. In this case, the positions of the coated portion and the uncoated portion are the same on both the front and back sides of the resin layer. For example, the uncoated portion on the back surface of the resin layer is compared to the uncoated portion on the surface of the resin layer. Are arranged on the opposite side.

JP 2003-92100 A JP 2011-159434 A

  Here, when an uncoated part exists in the same position in the front and back both surfaces of a resin layer, in the said uncoated part, the tolerance with respect to heat shrink is low. For this reason, inconveniences such as poor welding due to heat shrinkage may occur.

  Moreover, the separator of patent document 2 assumes the strip | belt-shaped thing used for the electrode assembly of a winding body. On the other hand, in the bag-like separator as in Patent Document 1, there are circumstances peculiar to the welding mode. That is, in the bag-shaped separator, the separators constituting the bag-shaped separator need to be welded to each other, but other than that, for example, it is not necessary to weld the bag-shaped separator and the negative electrode sheet.

  An object of the present invention is to provide an electrode storage separator and a power storage device capable of improving resistance to thermal shrinkage while firmly fixing the separator in a state where the electrode is stored inside.

  An electrode storage separator that solves the above problems includes separators that oppose each other, and sandwiches electrodes between the separators, and the opposing surface that is the side facing the electrodes in the separator is coated with ceramics. A coating part that is disposed at least in part corresponding to the periphery of the electrode and is welded to the opposing separator, and is coated with the ceramic except for the welding part on the opposing surface The entire non-facing surface on the side opposite to the facing surface of the separator is a coated portion coated with the ceramic.

  According to this configuration, since the ceramic is not coated on a part of the facing surface and there is a welded portion welded to the facing separator, the separators can be fixed with the electrodes sandwiched therebetween. . Moreover, the whole non-facing surface opposite to the facing surface other than the welded portion on the facing surface is a coated portion coated with ceramics. Thereby, the tolerance with respect to heat contraction can be aimed at. In particular, since the ceramic is also coated on the non-facing surface on the side opposite to the welded portion, the resistance to heat shrinkage at the welded portion is enhanced. For the sake of convenience, the “opposite surface” does not indicate only the portion facing the electrode of the separator, but indicates the entire surface including the portion facing the electrode.

  About the said electrode storage separator, the said separator is square shape, and the said welding part is good to have along at least one part of the opposite side of this separator in the said separator. According to this configuration, it is possible to fix the separators coated with ceramics at the minimum necessary locations.

  About the said electrode storage separator, it is good for the said welding part to exist in the whole region in the one side of the said separator. According to this configuration, since the welding area can be ensured as wide as possible, the separators can be attached and fixed more firmly.

  About the said electrode storage separator, the said welding part is good to have along each 4 sides of the said separator. According to this configuration, since the welded portion is present on each of the four sides of the separator, the electrode is not easily detached from the separator. Therefore, it can suppress suitably that an electrode will be exposed.

  About the said electrode accommodation separator, the said electrode has a tab protruded from the edge part, the said separator is square shape, and the said welding part is good in one side of the said tab side in the said opposing surface. According to this configuration, the excessive movement of the electrode in the direction along one side of the tab side is suppressed by the contact between the welded portion and the tab. Thereby, the position shift of the electrode in the direction along one side of the tab side can be suppressed.

  About the said electrode storage separator, the said electrode may be a positive electrode. According to this configuration, for example, the outer dimension of the electrode storage separator and the outer dimension of the negative electrode can be matched, so that when the electrode assembly is assembled, the electrode storage separator and the negative electrode are alternately stacked. Positioning when going is easy.

  The power storage device may include the above-described electrode storage separator, an electrode assembly in which electrodes having different polarities from the electrodes of the electrode storage separator are alternately stacked, and an electrolytic solution. According to this configuration, the productivity of the power storage device can be improved by using the electrode housing separator in the electrode assembly. Moreover, the coating part which exists in the whole non-opposing surface other than the welding part in an opposing surface is a porous film. For this reason, electrolyte solution is hold | maintained at a coating part. Thereby, the battery characteristic can be improved.

  The power storage device may be a secondary battery.

  According to the present invention, it is possible to improve resistance to heat shrinkage while firmly fixing the separator in a state where the electrode is housed inside.

The disassembled perspective view which shows the structure of the secondary battery of one Embodiment. The perspective view which shows the external appearance of a secondary battery. The disassembled perspective view which shows the structure of an electrode assembly. Sectional drawing which shows the location where the lead was welded in the current collection part. Sectional drawing of an electrode storage bag-shaped separator. The perspective view of a separator sheet. The top view of an electrode storage bag-shaped separator. Explanatory drawing which shows the state which set the positive electrode sheet to the separator sheet base material. Explanatory drawing which shows the state by which the separator sheet base material in which the positive electrode sheet was set was welded. Explanatory drawing which shows the state which cut | disconnects the separator sheet base material after welding. Explanatory drawing which shows the manufacture example of the electrode storage bag-shaped separator of another example. The top view of the electrode storage bag-shaped separator of another example.

  Hereinafter, one embodiment of an electrode storage separator and a power storage device will be described with reference to FIGS. A secondary battery as a power storage device is mounted on a vehicle such as a hybrid vehicle (plug-in hybrid vehicle) or an EV vehicle, and is used as a power source for a motor (not shown) used as a drive source of the vehicle. .

  As shown in FIGS. 1 and 2, the secondary battery 1 includes, for example, a metal case 2, and an electrolytic solution 4 and an electrode assembly 5 that is a power generation element are accommodated in the case body 3. Yes. The upper opening 3 a of the case body 3 is sealed in a sealed state by a metal plate-like case lid 6.

  As shown in FIG. 2, a positive electrode terminal 7 that is a positive electrode terminal and a negative electrode terminal 8 that is a negative electrode terminal are provided on the upper surface of the secondary battery 1. The positive electrode terminal 7 and the negative electrode terminal 8 are exposed to the outside of the case 2 from the opening hole 6 a (see FIG. 1) of the case lid 6. Ring-shaped insulating members 9 that insulate the positive terminal 7 and the negative terminal 8 from the case 2 are attached between the positive terminal 7 and the negative terminal 8 and the case 2.

  As shown in FIG. 3, the electrode assembly 5 is a layer composed of a bag-like separator (hereinafter referred to as an electrode-containing bag-like separator 10) in which an electrode (positive electrode) is housed in a bag, and a thin negative electrode sheet 11 that serves as a negative electrode. A plurality of layers. The electrode storage bag-shaped separator 10 is a member in which a thin positive electrode sheet 13 serving as a positive electrode is stored in a bag-shaped separator body 12. The electrode assembly 5 is a laminate in which electrode storage bag-like separators 10 and negative electrode sheets 11 are alternately laminated in a certain direction along the thickness direction of the electrode assembly 5 (stacking direction: Y-axis direction in FIG. 1 and the like). Structure.

  The positive electrode sheet 13 is provided with a metal sheet-like foil 14, and the positive electrode active material layer 15 is applied to both surfaces of the foil 14, so that this portion exists as a coating portion 16. A part of the foil 14 protrudes as a tab on a part of the periphery of the positive electrode sheet 13, and this part exists as an uncoated part 17 where the positive electrode active material layer 15 is not applied. That is, in this example, the positive electrode sheet 13 has a tab protruding from the edge thereof, and the tab corresponds to the uncoated portion 17. The negative electrode sheet 11 is also provided with a metal sheet-like foil 18, and a negative electrode active material layer 19 is applied to both surfaces of the foil 18. As with the positive electrode sheet 13, there are a coated portion 20 and an uncoated portion 21. To do.

  As shown in FIGS. 1 and 4, each of the positive electrode sheet 13 and the negative electrode sheet 11 has a lead in each current collecting part 22, 23 in which uncoated parts 17, 21 having the same polarity are bundled in the stacking direction Y. 24 and 25 are welded to each other. The leads 24 and 25 are fixed to the current collectors 22 and 23 with the vicinity of the roots of the current collectors 22 and 23 as welds 26 and 27. Further, the positive terminal 7 is connected to the positive lead 24 and the negative terminal 8 is connected to the negative lead 25. The current collectors 22, 23 protrude upward from the upper surface of the electrode pair 28 that is the main body of the electrode assembly 5, and are positioned closer to the ends on the side away from each other in the width direction of the electrode pair 28 (X-axis direction in FIG. 1). Is arranged.

  As shown in FIGS. 3 to 5, the electrode storage bag-shaped separator 10 is formed by stacking two separator sheets 29 each having a quadrangular shape as a pair of separators so as to face each other. 29a) and the other end (the lower side 29b of the paper surface) are welded to form a bag. As a result, the electrode storage bag-shaped separator 10 is provided with a storage portion 30 including a gap, and the positive electrode sheet 13 is stored in the storage portion 30. The separator sheet 29 is a sheet member that insulates the positive electrode sheet 13 and the negative electrode sheet 11. The storage unit 30 corresponds to the inside of the bag. In this example, the upper side 29a corresponds to “one side on the tab side”, and the lower side 29b corresponds to “the other side opposite to one side on the tab side”.

  As shown in FIGS. 5 and 6, a coating portion 31 coated with ceramics is present on the facing surface 29 c that is the surface facing the positive electrode sheet 13 in each separator sheet 29. The coat portion 31 exists in substantially the entire area of the facing surface 29c except for the upper side 29a and the lower side 29b that are opposite sides. Further, the entire non-facing surface 29 d on the side opposite to the facing surface 29 c in each separator sheet 29 is a coat portion 31. The coat portion 31 is laminated on the sheet base material 29s of the separator sheet 29, and is a porous film having higher rigidity than the sheet base material 29s.

  The upper side 29a and the lower side 29b of the facing surface 29c of each separator sheet 29 corresponding to the peripheral edge of the electrode are uncoated portions 32 that are not coated with ceramics. In the case of this example, the uncoated portion 32 on the upper side 29a of the facing surface 29c is referred to as an upper end side uncoated portion 32a, and the uncoated portion 32 on the lower side 29b of the facing surface 29c is referred to as a lower end side uncoated portion 32b. The upper end side uncoated portion 32a and the lower end side uncoated portion 32b are present in the entire region in the width direction of the electrode storage bag-shaped separator 10 (X-axis direction in FIG. 6). Although the pair of separator sheets 29 are ceramic coated, they can be welded at the uncoated portions 32a and 32b.

  As shown in FIG. 5 to FIG. 7, the pair of separator sheets 29 is welded to the entire length direction (X-axis direction in FIG. 7) of the uncoated portions 32 a and 32 b on the facing surface 29 c, thereby It becomes the welding part 33 and is attached and fixed to the bag shape. The welding method (welding portion 33) may be either intermittent welding or continuous welding. In the case of this example, the welded portion 33 in the upper uncoated portion 32a is the upper welded portion 33a, and the welded portion 33 in the lower uncoated portion 32b is the lower welded portion 33b.

  Incidentally, in this specification, when the welding part 33 is intermittent welding, the area | region between welding parts shall also be contained in the welding part 33. FIG. For this reason, when the welding part 33 is intermittent welding, the area | region between the welding parts which exist intermittently except the welding part 33 in the opposing surface 29c is excluded.

  The positive electrode sheet 13 is positioned in the vertical direction (Z-axis direction in FIG. 7) in the storage unit 30 by being sandwiched from above and below by the upper welded portion 33a and the lower welded portion 33b. Further, the uncoated portion 17 of the positive electrode sheet 13 has a pair of welded portions (electrode positioning welded portions) 33c that are part of the upper welded portion 33a at the base portion, and is disposed in the vicinity of the paper surface in the storage portion 30. They are positioned in the left-right direction (X-axis direction in FIG. 7: tab surface direction).

In this example, it is assumed that a region between the electrode positioning welded portions 33 c that is a region facing the uncoated portion 17 in the facing surface 29 c is included in the welded portion 33.
The operation of this embodiment will be described.

  The welded portion 33 of the facing surface 29c is an uncoated portion 32 that is not coated with ceramics. On the other hand, the entire non-facing surface 29d other than the welded portion 33 of the facing surface 29c is a coated portion 31 coated with ceramics. For this reason, the coating part 31 exists also in the location on the opposite side of the welding part 33 in the non-facing surface 29d (refer FIG. 4 etc.).

Next, the manufacturing process of the electrode storage bag-like separator 10 of this example will be described with reference to FIGS.
As shown in FIG. 8, in the electrode storage bag-shaped separator manufacturing process, the upper side and the lower side of one surface have uncoated portions 32a and 32b that are not coated with ceramics, and the uncoated portion 32a on the one surface. , 32b and the other surface as a whole are prepared as a pair of long strip-shaped separator sheet base materials 34 coated with ceramics.

  Incidentally, a plurality of separator sheet base materials 34 are stacked in a predetermined magazine. In the electrode storage bag-shaped separator manufacturing process, the separator sheet base material 34 is taken out from the magazine one by one using an arm or the like and placed in a predetermined work space.

  And a pair of separator sheet base material 34 is arrange | positioned so that one surface where the uncoated parts 32a and 32b exist may mutually oppose. A plurality of positive electrode sheets 13 are arranged side by side between a pair of separator sheet base materials 34, and these positive electrode sheets 13 are sandwiched and set by a pair of separator sheet base materials 34.

  Subsequently, as shown in FIG. 9, the pair of separator sheet base materials 34 overlapped at the upper end side uncoated portion 32 a and the lower end side uncoated portion 32 b, whereby the positive electrode sheet 13 is separated into two separator sheets. The substrate 34 is wrapped and integrated (unitized). That is, a pair of strip-shaped separator sheet base material 34 and a plurality of positive electrode sheets 13 are assembled as a strip-shaped separator unit 35. Thereby, the separator sheet base material 34 is formed in a bag shape, and the positive electrode sheet 13 is stored in the internal storage portion 30. At the time of welding, the left and right sides of the positive electrode sheet 13 are sandwiched between the electrode positioning welds 33c, thereby positioning the positive electrode sheet 13 in the left-right direction (X-axis direction in FIG. 9).

  Then, as shown in FIG. 10, one strip-shaped separator unit 35 is cut between the adjacent positive electrode sheets 13 to form each electrode-containing bag-shaped separator 10. Various cutting methods such as punching and cutting can be used. Thus, a plurality of electrode storage bag-shaped separators 10 are formed from one strip-shaped separator unit 35.

  Subsequently, a method for manufacturing the secondary battery 1 using the electrode storage bag-shaped separator 10 will be described. First, the electrode storage bag-shaped separator 10 and the negative electrode sheet 11 are alternately stacked. Then, after overlapping the required number, uncoated portions 17 and 21 having the same polarity are bundled together, the leads 24 and 25 are welded, and the electrode assembly 5 is assembled. After assembling the electrode assembly 5, the electrode assembly 5 and the electrolyte solution 4 are accommodated in the case body 3, and the opening 3 a of the case body 3 is closed with the case lid 6, whereby the secondary battery 1 is assembled.

According to the configuration of the present embodiment, the following effects can be obtained.
(1) In the separator sheet 29 of the electrode storage bag-shaped separator 10, a facing surface 29 c that is a surface facing the positive electrode sheet 13 is disposed along the upper side 29 a and the lower side 29 b of the separator sheet 29. And a welded portion 33 welded to each other. Since the welded portion 33 is not coated with ceramics and the sheet base material 29s is exposed, the weld strength is improved.

  The entire non-facing surface 29d other than the welding portion 33 of the facing surface 29c is a coated portion 31 coated with ceramics. Thereby, the improvement of the tolerance with respect to heat contraction can be aimed at at the maximum. In particular, since the coat portion 31 is also present on the opposite side of the non-facing surface 29d from the weld portion 33, resistance to heat shrinkage at the weld portion 33 is enhanced.

  Further, the rigidity of the coat portion 31 is higher than that of the sheet base material 29s. For this reason, since the part on the opposite side to the uncoated part 32 in the non-facing surface 29d is the coated part 31, the upper side 29a and the lower side 29b of the separator sheet 29 are not easily curved. Therefore, when the pair of separator sheet base materials 34 are overlapped, both can be easily aligned and positional deviation can be suppressed.

  Furthermore, since the upper side 29a and the lower side 29b of the separator sheet 29 are not easily curved as described above, the upper side and the lower side of the electrode storage bag-shaped separator 10 are also difficult to bend. Thereby, when the electrode storage bag-shaped separator 10 and the negative electrode sheet 11 are laminated at the time of assembling the electrode assembly 5, both can be easily aligned and positional deviation can be suppressed.

Moreover, since the coat part 31 is a porous film, the electrolyte solution 4 is held by the coat part 31. Thereby, the battery characteristic can be improved.
In particular, since both the facing surface 29c and the non-facing surface 29d have the coat portion 31, the resistance to heat shrinkage can be further improved as compared with the configuration in which the coat portion 31 is provided only on one side, and the positive electrode The liquid retention effect can be improved with respect to both the side and the negative electrode side.

  Moreover, since the coating part 31 exists in both the opposing surface 29c and the non-facing surface 29d, the coating parts 31 will contact in the state in which the separator sheet base material 34 is laminated | stacked on the magazine. In this case, since both are ceramics of the same material, it is difficult to polarize and triboelectric charge hardly occurs. Thereby, in the electrode storage bag-shaped separator manufacturing process, when the separator sheet base material 34 is taken out from the magazine, the problem that two sheets are taken out at the same time hardly occurs. Therefore, the productivity can be further improved.

  (2) By enclosing the positive electrode sheet 13 in advance with two separator sheets 29, these are placed as one part called an electrode storage bag-shaped separator 10, and the electrode storage bag-shaped separator 10 and the negative electrode sheet 11 are alternately stacked. Thus, the electrode assembly 5 is assembled. For this reason, when assembling the electrode assembly 5, the number of stacked sheets imposed in the stacking process can be reduced, and the tact time of production is shortened. Therefore, the productivity of the electrode assembly 5 and thus the secondary battery 1 can be improved.

  (3) The positive electrode (positive electrode sheet 13) among the positive and negative electrodes is stored in the electrode storage bag-shaped separator 10. By the way, in this kind of electrode assembly 5, it is necessary to make a negative electrode larger than a positive electrode on the relationship of the exchange of the ion between electrodes. For this reason, if the positive electrode is stored inside the electrode storage bag-shaped separator 10 as in this example, as a result, the outer dimension of the electrode storage bag-shaped separator 10 and the outer dimension of the negative electrode sheet 11 are the same. It can take the dimension to do. Therefore, when the electrode assembly 5 is assembled, alignment when the electrode storage bag-shaped separator 10 and the negative electrode sheet 11 are alternately stacked is facilitated. Further, in the electrode assembly 5, the stacked electrode storage bag-shaped separator 10 and the negative electrode sheet 11 are not easily displaced.

  (4) The welded portions 33a and 33b are provided along the upper side 29a and the lower side 29b in the separator sheet 29 coated with ceramics. Thereby, the separator sheet 29 can be fixed at a minimum necessary location. Moreover, the position shift | offset | difference of the positive electrode sheet 13 in the opposing direction of the upper side 29a and the lower side 29b is controlled by each welding part 33a, 33b. Thereby, it is possible to prevent the positive electrode sheet 13 from being detached from the pair of separator sheets 29.

  Further, since there is an uncoated portion 32 along the upper side 29a and the lower side 29b, after setting the positive electrode sheet 13 between the pair of separator sheets 29, the pair of separator sheets 29 is formed into a bag shape with the uncoated portions 32a and 32b. The electrode storage bag-shaped separator 10 can be manufactured by a simple process of welding and cutting the adjacent positive electrode sheet 13.

  (5) The welded portions 33a and 33b are provided over the entire upper side 29a and lower side 29b of the separator sheet 29. For this reason, since the welding area of the separator sheet 29 can be ensured widely, a pair of separator sheet 29 can be more firmly attached and fixed.

  (6) The upper welded portion 33 a is on the upper side 29 a that is one side of the tab side of the facing surface 29 c of the separator sheet 29. Specifically, on both sides of the uncoated portion 17 of the positive electrode sheet 13, there are some electrode positioning welded portions 33 c of the upper welded portion 33 a. For this reason, the uncoated portion 17 of the positive electrode sheet 13 is positioned by the electrode positioning welded portion 33c in the left-right direction on the paper surface, that is, in the direction along the upper side 29a. Can be difficult.

  In particular, as described above, the displacement of the positive electrode sheet 13 in the opposing direction of the upper side 29a and the lower side 29b is regulated by the lower welded portion 33b on the lower side 29b that faces the upper side 29a. Therefore, the positional deviation of the positive electrode sheet 13 with respect to the separator sheet 29 can be suitably suppressed without providing a welded portion on the left side or right side of the separator sheet 29.

Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.
As shown in FIG. 11, after preparing a large separator sheet 41 and arranging the positive electrode sheet 13 thereon, the separator sheet 41 is folded back at the center, so that the positive electrode sheet 13 is separated from the front and back by the separator sheet 41. It may be wrapped up. In this case, the electrode storage bag-shaped separator 10 can be manufactured in a simple form in which one separator sheet 41 is bent.

-The welding part 33 is not limited to existing in the whole upper side 29a (lower side 29b), For example, you may exist partially.
-The welding part 33 may exist in the left side, the right side, etc. of the paper surface of the separator sheet 29, for example.

  As shown in FIG. 12, the welded portion 33 may be along each of the four sides of the separator sheet 29. In this case, as shown in FIG. 12, there may be welded portions 33 in the entire area of each of the four sides, some of the four sides have welded portions 33 partially, and the other sides There may be a welded portion 33 in the entire region. According to such a configuration, the positive electrode sheet 13 is not easily detached from the separator sheet 29. Thereby, the inconvenience that the positive electrode sheet 13 is detached and exposed from the separator sheet 29 can be suitably suppressed. Thus, the bag shape of the electrode storage bag-shaped separator 10 is sufficient if it can wrap the positive electrode sheet 13, and includes a cylindrical shape in which two sides are welded and a shape in which four sides are welded.

-The magnitude | size (area) of the welding part 33 can be changed suitably.
The upper welded portion 33a and the lower welded portion 33b may have different lengths.
The ceramic separator may be a sheet coated with ceramics only on at least the facing surface 29c.

The direction when the positive electrode sheet 13 is arranged on the separator sheet 29 may be a direction in which the positive electrode sheet 13 is rotated about 90 degrees in the left direction in FIG.
The electrode storage bag-shaped separator 10 is not limited to being manufactured by setting a plurality of positive electrode sheets 13 on one long strip-shaped separator sheet base material 34 and cutting them in units of the positive electrode sheet 13. For example, the separator sheet 29 previously cut to a final size may be used, the positive electrode sheet 13 may be set on the separator sheet 29, and the periphery may be welded.

The positive electrode terminal 7 and the negative electrode terminal 8 are not limited to being arranged on the same side of the electrode pair 28, and may be arranged on different sides.
The arrangement position of the current collectors 22 and 23 is not limited to the upper surface of the electrode pair 28 but can be changed to the side surface or the lower surface.

-The positive electrode current collection part 22 is not limited to one, For example, multiple may be sufficient and these may be electrically connected by one or several lead | read | reeds. The same can be said for the negative electrode current collector 23.
-A positive electrode and a negative electrode are not limited to a sheet-like member, For example, you may use the plate-shaped member with predetermined amount thickness.

-The raw material of the positive electrode sheet 13, the negative electrode sheet 11, and the separator sheet 29 can be changed suitably.
-The structure of the positive electrode terminal 7, the negative electrode terminal 8, and the current collection parts 22 and 23 is not restricted to the example described in embodiment, It can change into another structure.

The opening 3 a of the case body 3 is not limited to the upper surface of the case body 3, and can be changed to another location such as a side surface of the case body 3.
-The electrode assembly 5 is not limited to a laminated structure, It is good also as a winding structure which winds a sheet-like electrode pair in many layers, and has a positive / negative electrode layer.

-An electrical storage apparatus is not limited to a secondary battery, For example, it is good also as an electrical storage charged / discharged with an electric double layer capacitor.
-The electrode in the electrode storage bag-shaped separator 10 is not limited to a positive electrode, It is good also as a negative electrode.

  -Various types of welding such as spot welding, butt welding, and projection welding can be used for lead welding (resistance welding). Further, the welding is not limited to resistance welding, and other methods can be adopted.

The separator shape is not limited to a square shape, and can be appropriately changed to various shapes. Further, the “square shape” includes, for example, a chamfered corner of a rectangular separator.
The electrode assembly 5 (secondary battery 1) is not limited to being mounted on a vehicle, and can be mounted on other devices and apparatuses.

A preferred example that can be grasped from the embodiment and another example will be described below.
(A) In an electrode storage separator provided with separators facing each other and sandwiching electrodes between the separators, a facing surface that is a surface facing the electrodes in the separator is disposed at least at a part corresponding to the periphery of the electrodes An uncoated portion that is not coated with ceramics, the uncoated portions of the separator being welded at least in part, and other than the uncoated portion on the facing surface, and the facing surface in the separator An electrode storage separator, wherein the entire non-facing surface on the opposite side of the electrode is a coated portion coated with the ceramics.

  (B) The welded portion may be disposed on one side of the tab side and the other side facing the one side, and may be disposed on both sides in the tab surface direction on the one side.

  DESCRIPTION OF SYMBOLS 1 ... Secondary battery as an electrical storage device, 4 ... Electrolyte solution, 5 ... Electrode assembly, 10 ... Electrode storage bag-shaped separator as an electrode storage separator, 11 ... Negative electrode sheet which comprises an electrode, 13 ... Positive electrode which comprises an electrode Sheet, 17 ... Uncoated part as tab, 29 ... Separator sheet (separator), 29a ... Upper side, 29b ... Lower side, 29c ... Opposing surface, 29d ... Non-opposing surface, 30 ... Storage part, 31 ... Coated part, 32 (32a, 32b) ... uncoated part, 33 (33a, 33b, 33c) ... welded part.

Claims (8)

In an electrode storage separator comprising separators facing each other and sandwiching an electrode between the separators,
The facing surface which is the surface facing the electrode in the separator is not coated with ceramics, and is disposed on at least a part corresponding to the peripheral edge of the electrode, and is welded to the facing separator. Part
Other than the welded portion on the facing surface, the coated portion is coated with the ceramic, and the entire non-facing surface on the side opposite to the facing surface in the separator is the coated portion coated with the ceramic. An electrode storage separator.   The electrode storage separator according to claim 1, wherein the separator has a square shape, and the welded portion is along at least part of the opposite side of the separator in the separator.   The electrode storage separator according to claim 2, wherein the welded portion is located on the entire side of one side of the separator.   The electrode storage separator according to claim 2, wherein the welded portion is provided along each of the four sides of the separator. The electrode has a tab protruding from its edge;
The electrode separator according to any one of claims 1 to 4, wherein the separator has a square shape, and the welded portion is located on one side of the opposing surface on the tab side.   The electrode storage separator according to any one of claims 1 to 5, wherein the electrode is a positive electrode. An electrode assembly in which the electrode storage separator according to any one of claims 1 to 6 and electrodes having different polarities from the electrodes of the electrode storage separator are alternately stacked;
An electrolyte,
A power storage device.   The power storage device according to claim 7, wherein the power storage device is a secondary battery.