CN109075286A

CN109075286A - Energy storage device

Info

Publication number: CN109075286A
Application number: CN201680076861.5A
Authority: CN
Inventors: Y.山本
Original assignee: Lithium Energy and Power GmbH and Co KG
Current assignee: Lithium Energy and Power GmbH and Co KG
Priority date: 2015-10-29
Filing date: 2016-07-26
Publication date: 2018-12-21
Also published as: WO2017071846A1; JP2017084680A

Abstract

A kind of energy storage device is provided, electrode assembly closed safe valve can be prevented when discharging safety valve.Energy storage device (100) includes by the way that positive electrode (21) and negative electrode (22) are stacked to the electrode assembly formed each other (20)；And container (10) comprising the safety valve (70) being formed in the The lid component (12) of the wall part of container (10).In electrode assembly (20), hole section (27) are formed on the edge (2lab) of at least one layer of positive electrode (21) and/or the edge (22ab) of negative electrode (22) of neighbouring The lid component (12) setting, it is formed by notch part (2lad) and/or notch part (22ad), and is extended along the direction far from The lid component (12).

Description

Energy storage device

Technical field

The present invention relates to energy storage devices, and wherein safety valve is mounted on container.

Background technique

The energy storage device of similar such as lithium ion secondary battery, for instance it is known to include electrode assembly accommodates electrode assembly The energy storage device of container, electrode terminal and electrolyte (electrolyte solution in such as container).When in energy storage device It is middle occur such as overcharge, hit or adhere abnormality when, it is understood that there may be due to electrolyte decomposition and generate gas So that the increased situation of internal pressure in container.In order to cope with the state, container can be constructed to discharge gas generated Body.

For example, patent document 1 describes a kind of non water electrolyte solution secondary battery, it is one of energy storage device Example, that is, non-aqueous electrolyte secondary battery.The non water electrolyte solution secondary battery include bottom rectangle cylindrical shell, The sealing element of opening for seal casinghousing, formation accommodate the electrode group of flat electrode component in the housing and formation is filled out Fill the non-aqueous electrolytic solution of electrolyte in the housing.By by band-like positive electrode, band-like negative electrode and band-like diaphragm (separator) it is intertwined to form electrode group.Band-like positive electrode includes being formed in a side edge in a manner of projection Multiple positive electricity electrode current collector tabs (postive electrode collector tab).Band-like negative electrode includes with projection Multiple negative electricity electrode current collector tabs that mode is formed in a side edge.In the electrode group by being wound, to face Multiple positive electricity electrode current collector tabs that face mode positions are connected electrically to the plus end formed on sealing element, and with face-to-face Multiple negative electricity electrode current collector tabs that mode positions are connected electrically to the negative terminal formed on sealing element.

By making a part of thinning of sealing element, safety valve is formed on sealing element.In safety valve, when by shell The pressure increase in case inside that hermetically seals with sealing element and when beyond predetermined value, safety valve is corrupted such that energy Enough prevent the rupture of non water electrolyte solution secondary battery.

Existing technical literature

Patent document

Patent document l:JP-A-2011-70916.

Summary of the invention

Problem to be solved by this invention

In the recent period, it is desirable that the energy storage device of such as lithium ion secondary battery meets the high input and high output of electrical power.Therefore, When above-described abnormality occurs in energy storage devices, due to the decomposition of electrolyte, bulk gas is generated suddenly. In the non water electrolyte solution secondary battery described in patent document 1, when the increase in response to the pressure of case inside is released When putting safety valve, may exist a kind of situation, wherein due to the gas generated by the gas sprayed with high injection pressure from safety valve Body flowing, electrode group is mobile towards sealing element, while deforms positive electricity electrode current collector tab and negative electricity electrode current collector tab, and Closed safe valve.

The present invention has been set to overcome disadvantages mentioned above, and the object of the present invention is to provide a kind of energy storage device, it can Prevent electrode group (that is, electrode assembly) closed safe valve when discharging safety valve.

The means solved the problems, such as

To achieve the goals above, the present invention relates to a kind of energy storage devices comprising by the way that electrode plate to be stacked to each other The electrode assembly and container of formation, wherein form safety valve on wall of a container part, and be arranged extremely in neighbouring wall part The concave portion extended along the direction far from wall part is formed on the marginal portion of few one layer of electrode plate.

In above-mentioned construction, wherein when the pressure increase in container is released safety valve electrode assembly towards wall In the situation of partial movement, concave portion can ensure the space between electrode assembly and wall part.Accordingly, it is possible to prevent safety Valve is closed by electrode assembly, and therefore, can discharge increased pressure with stationary mode.

At least part of concave portion may be configured to relative mode in face of safety valve.With this construction, concave portion It can ensure the space at the position that wherein concave portion faces safety valve with relative mode, and accordingly, it is possible to more easily Prevent electrode assembly closed safe valve.

Electrode assembly be configured so to by winding electrode plate formed electrode assembly, and the winding axis of electrode assembly with Wall part intersection.With this construction, even if in the lateral winding-type electrode assembly that can output and input high electrical power, it can also It can ensure the space between electrode assembly and wall part when electrode assembly is mobile towards wall part.

Multiple concave portions can be formed on electrode plate, so that concave portion is arranged to along the stacking direction of electrode plate Row.With this construction, the space formed by concave portion overlaps each other along the stacking direction of electrode plate.Therefore, concave portion increases It is added in the space limited between electrode assembly and wall of a container part, and accordingly, it is possible to more easily prevents electrode assembly from closing Safety valve.

Electrode plate can have the edge for the electrode plate being arranged at the position for being different from concave portion from neighbouring wall part The tab of portion projects.With this construction, in a concave manner along further from the direction of wall of a container part from the edge of electrode plate Partially (being formed on tab) forms concave portion.Therefore, even if working as electrode assembly towards wall of a container in tab deformation When partial movement, concave portion can also ensure that the space limited between electrode assembly and wall of a container part.

Advantages of the present invention

Energy storage device according to the present invention may prevent electrode assembly closed safe valve when discharging safety valve.

Detailed description of the invention

Fig. 1 is the perspective view for schematically showing the appearance of energy storage device of embodiment according to the present invention.

Fig. 2 is the decomposition perspective view of energy storage device shown in Fig. 1.

Fig. 3 is the perspective view that a part of electrode assembly shown in Fig. 2 is shown in a manner of expansion (developed).

Fig. 4 is the decomposition perspective view of The lid component shown in Fig. 2.

Fig. 5 is the cross-sectional side view of energy storage device shown in Fig. 1.That is, Fig. 5 is shown such as along direction The energy stores that the plane at the center of the short side wall of vessel along the long side wall for being parallel to vessel of V observation intercepts The view of the cross section of device.

Fig. 6 be along VI-VI interception Fig. 5 shown in energy storage device cross-sectional side view.

Fig. 7 is substantially equal to the decomposition perspective view of Fig. 2, shows the energy storage device of embodiment according to the present invention The construction of remodeling.

Fig. 8 is the perspective view that a part of electrode assembly shown in fig. 7 is shown with expansion mode.

Specific embodiment

Hereinafter, the energy storage device of embodiment according to the present invention is described with reference to the drawings.It is described below All embodiments describe comprehensive example or specific example.In the embodiment being described below, numerical value, shape, material, composition Element, the position of constituent element and connection status etc. are only example, and these are not intended to the limitation present invention.This Outside, in the constituent element in embodiment being described below, not in the independent claims for describing most important design The constituent element of description is described as arbitrary constituent element.

In addition, attached drawing is schematic views, and therefore, in the accompanying drawings, constituent element is not always described strictly.Corresponding attached In figure, give same or like constituent element identical symbol.In the description of embodiment done in below, exist using companion With the statement having " substantially ", such as situation of " substantially parallel " or " substantially orthogonal ".In these cases, for example, it is " substantially flat Row " does not mean only that " completely parallel to each other ", and also implies that " being substantially parallel to one another ".That is, for example, " substantially flat Row " also includes the depth of parallelism of several percentages approximate with " degree of being substantially parallel " such as difference.Identical situation is suitable for being accompanied by " substantially " other statements.

Embodiment

Describe the construction of energy storage device 100 according to the embodiment.Fig. 1 be schematically show it is according to the embodiment The perspective view of the appearance of energy storage device 100.As shown in fig. 1, energy storage device 100 has flattened rectangular parallel six The exterior contour of face shape.Energy storage device 100 is the secondary cell that can be charged and discharged.For example, more specifically, energy Amount storage device 100 is formed by the non-aqueous electrolyte secondary battery of such as lithium ion secondary battery.However, energy storage device 100 are not limited to non-aqueous electrolyte secondary battery, and can be the secondary cell other than non-aqueous electrolyte secondary battery, or It can be capacitor.

The construction of energy storage device 100 is described with reference to Fig. 1 and Fig. 2, energy storage device 100 includes having flattened rectangular The container 10 of parallelepiped shape, the electrode assembly 20 being housed in container 10, positive electrode terminal 30 and negative electrode terminal 40. Fig. 2 is the decomposition perspective view of energy storage device 100 shown in Fig. 1.

Container 10 includes the vessel 11 for having angle cylindrical shape of bottom, and the lid structure with elongate rectangular plate shape Part 12, the The lid component 12 can close the opening portion 11a of vessel 11.Vessel 11 has flattened rectangular parallel The exterior contour of hexahedral shape, and including with elongate rectangular shape bottom wall l1b and four side walls 11c, l1d, l1e and 11f, each of which all has the rectangular shape erect vertically from four edges of bottom wall 11b.Side wall 11c and 11e be positioned to Just it is faced each other with relative mode, and each of side wall 11c and l1e are respectively formed the long side wall with big width (below In, side wall 11c and 11e are also referred to as " long side wall 11c and 11e ").Side wall 11d and 11f are positioned to face with relative mode Each other, and each of side wall l1d and 11f are respectively formed short side wall (hereinafter, the side wall l1d and 11f with small width Referred to as " short side wall l1d and 11f ").Opening portion 11a has the elongate rectangular shape for the shape for being substantially equal to bottom wall 11b.Just Electrode terminal 30 and negative electrode terminal 40 are arranged on the outer surface 12a of The lid component 12.In positive electrode terminal in The lid component 12 Middle position between 30 and negative electrode terminal 40 forms safety valve 70.It is described later on the construction of safety valve 70.In the implementation In example, The lid component 12 is an example of the wall part of container 10.

Vessel 11 and The lid component 12 can by the connecting method that such as welds with a kind of state be fixed to each other, In the state, the joining part of vessel 11 and the joining part of The lid component 12 are fixed to each other, while keeping attachment Divide and is in airtight conditions.With this construction, sealing space is formed in container 10.Vessel 11 and The lid component 12 can be by working as The internal pressure of container 10 can prevent deformation and vessel 11 and the lid structure of vessel 11 and The lid component 12 when increasing The material of the deterioration of the air-tightness of the joining part of part 12 is made.Although being used to form the material of vessel 11 and The lid component 12 It is unrestricted, but vessel 11 and The lid component 12 can be by the solderable metals of such as stainless steel, aluminum or aluminum alloy It is made.

The liquid of such as electrolyte solution (being non-aqueous electrolytic solution in this embodiment) is filled in as electrolyte In container 10.However, omitting the diagram of liquid.Concrete restriction will not be filled in the type of the electrolyte solution in container 10, and As long as not damaging the performance of energy storage device 100, it will be able to select various electrolyte solutions.

Positive electrode terminal 30 and negative electrode terminal 40 are by means respectively of positive electrode lead plate (lead plate) 51 and negative electricity Pole lead plate 61 is physically and electrically connected to the positive electricity from electrode assembly 20 towards the electrode assembly 20 of 12 projection of The lid component Electrode current collector tab group 24 and negative electricity electrode current collector tab group 25.

Electrode assembly 20 is power producing element, can be stored therein electric power.Electrode assembly 20 is formed so that Band-like positive electrode 21, band-like negative electrode 22 and band-like diaphragm 23 shown in Fig. 3 are stacked to each other, and stack ontology with multilayer side Formula is around winding axis A spiral winding.Fig. 3 be shown with expansion mode electrode assembly 20 shown in Fig. 2 a part it is saturating View.Although not limiting in this embodiment, electrode assembly 20 has flat exterior contour, and has elongated annular Cross-sectional shape.Winding axis A is the axis of imaginaries indicated by the chain-dotted line in Fig. 2, and electrode assembly 20 is relative to winding axis Line A is substantially symmetric.Winding axis A extends along the direction for being approximately perpendicular to The lid component 12, this is the direction intersected with The lid component 12. Electrode assembly 20 is arranged so that the edge of the positive electrode 21 extended along winding direction, negative electrode 22 and diaphragm 23 with relative mode In face of The lid component 12.The electricity in the direction that the outer surface 12a that wherein winding direction as described above is parallel to The lid component 12 extends Pole component 20 is referred to as lateral winding-type electrode assembly.

In electrode assembly 20, edge winding of the multiple positive electricity electrode current collector tab 21aa shown in Fig. 3 from positive electrode 21 The edge projection that direction extends, and the positive electricity electrode current collector tab 21aa by bonding multiple stackings forms positive electricity electrode current collector pole Ear group 24.In addition, multiple negative electricity electrode current collector tab 22aa are along identical with positive electricity electrode current collector tab 21aa shown in Fig. 3 The edge projection that direction extends from negative electrode 22 along winding direction, and the negative electricity electrode current collector tab by bonding multiple stackings 22aa forms negative electricity electrode current collector tab group 25.

Above-mentioned electrode assembly 20 is received in vessel 11 with a kind of state, in the state, electrode assembly 20 By means of positive electrode lead plate 51, negative electrode lead plate 61, positive electricity electrode current collector tab group 24 and negative electricity electrode current collector tab group 25 dangle from The lid component 12.In order to keep electrode assembly 20 and vessel 11 electrically isolated from one another, there may also be wherein by exhausted The situation of velum covering electrode group part 20.It is arranged between electrode assembly 20 and vessel 11 there may also be wherein and such as pads Enclose the situation of the bolster of (spacer).

It is described done in below and with description in related attached drawing, the electrode assembly 20 of energy storage device 100 The direction of winding axis A is referred to as z axis direction.Therefore, as shown in Figures 1 and 2, vessel 11 and The lid component 12 are with weight Folded mode is arranged along z axis direction, and the long edge z axis direction of the short side wall 11d and 11f of vessel 11 extend.In addition, In this embodiment, z axis direction can be defined as the vertical direction of energy storage device 100.

Depending on the use pattern of energy storage device 100, there may also be a kind of situations, wherein energy storage device 100, which are not set z axis direction wherein, is not limited for vertical direction, and therefore, and z axis direction is not necessarily restricted to erect Histogram to state in.

The width direction of energy storage device 100 is referred to as X-axis line direction, along from positive electrode terminal 30 towards negative electrode The direction of terminal 40 extends, and perpendicular to z axis.Therefore, positive electrode lead plate 51 and negative electrode lead plate 61 are along X-axis line direction Arrangement, and the short side wall 11d and 11f of vessel 11 being located on side relative to each other is arranged along X-axis line direction.

It is referred to as Y-axis line direction perpendicular to X-axis line direction and perpendicular to the direction in z axis direction.Therefore, vessel 11 The long side wall 11c and l1e being located on side relative to each other arranged along Y-axis line direction, and the short side wall of vessel 11 The short side of 11d and 11f extends along Y-axis line direction.In addition, Y-axis line direction can be defined as the thickness direction of container 10.

The detailed configuration of electrode assembly 20 is further described with reference to Fig. 3.Electrode assembly 20 includes having elongated, belt-shaped sheet material A positive electrode 21 of shape, shape with elongated, belt-shaped sheet material a negative electrode 22, and there is elongated, belt-shaped sheet material Shape two diaphragms 23, overlap each other the state of stratification in wherein electrode and diaphragm.By by positive electrode 21, negative electricity Pole 22 and diaphragm 23 are spirally wound together into form electrode assembly 20, and wherein positive electrode 21, negative electrode 22 and diaphragm 23 surround Winding axis A overlaps each other stratification along winding direction B.In this embodiment, by using positive electrode 21, negative electrode 22 and diaphragm 23 winding beginning is as winding axis A along winding direction B rotation positive electrode 21, negative electrode 22 and diaphragm 23, positive electrode 21, the unwound part of negative electrode 22 and diaphragm 23 is wound.That is, in winding positive electrode 21, negative electrode 22 and diaphragm It is the direction of rotation of electrode assembly 20 by the winding direction B counterclockwise indicated at the time of 23, in Fig. 3.

Positive electrode 21 is formed so that anode active material layer 21b(is indicated in Fig. 3 by shade) by such as coating Method be laminated to positive electrode substrate 21a(its elongated, belt-shaped metal foil made of the metal such as aluminum or aluminum alloy and formed) Substantially whole surface.Negative electrode 22 is formed so that anode active material layer 22b(is indicated in Fig. 3 by shade) by all As the method for coating is laminated to its elongated, belt-shaped metal made of the metal such as copper or copper alloy of negative electrode substrate 22a( Foil is formed) substantially whole surface.Use more microperforated sheets made of the material with electric insulation property such as resin Form diaphragm 23.

As the positive electrode active materials for being used to form anode active material layer 21b or it is used to form anode active material layer The negative electrode active material of 22b can use known material according to expectation, as long as the positive electrode active materials or the negative electrode active material Material can occlude (occlude) and release lithium ion.Anode active material layer 21b can be laminated in positive electrode substrate 21a Two sides on formed with big width and be positioned in major surfaces relative to each other one, or positive electricity can be laminated to Two major surfaces of pole substrate 21a.In the same manner, anode active material layer 22b can be laminated in negative electrode substrate Formed on the two sides of 22a with big width and be positioned in major surfaces relative to each other one, or can be laminated to Two major surfaces of negative electrode substrate 22a.

Along positive electrode substrate 21a longitudinal direction extension band-like positive electrode substrate 21a two edge 2lab and On an edge 2lab in 2lac, multiple positive electricity electrode current collector tab 21aa along positive electrode substrate 21a longitudinal direction with It is integrally formed every mode and positive electrode substrate 21a.Positive electricity electrode current collector tab 21aa is arranged so that as around winding axis A Positive electrode substrate 21a each circle provide a positive electricity electrode current collector tab 21aa.Positive electricity electrode current collector tab 21aa is orthogonal In positive electrode substrate 21a longitudinal direction along the direction of winding axis A from edge 2lab projection.Positive electricity electrode current collector tab 21aa From edge 21ab along with towards the opposite direction projection in the direction of edge 2lac.Positive electricity electrode current collector tab 21aa is by positive electrode base The expose portion of bottom 21a is formed, and does not include anode active material layer 21b.Other than positive electricity electrode current collector tab 21aa, just Pole active material layer 21b is also laminated to the region of positive electrode substrate 21a.The side of edge 2lab and 2lac formation positive electrode 21 Edge.

Along negative electrode substrate 22a longitudinal direction extension band-like negative electrode substrate 22a two edge 22ab and On an edge 22ab in 22ac, multiple negative electricity electrode current collector tab 22aa along negative electrode substrate 22a longitudinal direction with It is integrally formed every mode and negative electrode substrate 22a.When making negative electrode 22 and positive electrode 21 overlaps each other to wind, bear The edge 2lab positioning of the edge 22ab and positive electrode substrate 21a of electrode basement 22a are on the same side.Negative electricity electrode current collector tab 22aa is arranged so as to be negative electrode basement 22a around each circle one negative electricity electrode current collector tab of offer for winding axis A 22aa.Negative electricity electrode current collector tab 22aa is orthogonal to the longitudinal direction of negative electrode substrate 22a along the direction of winding axis A from edge 22ab projection.Negative electricity electrode current collector tab 22aa from edge 22ab along with towards the opposite direction projection in the direction of edge 22ac. Each negative electricity electrode current collector tab 22aa is formed by the expose portion of negative electrode substrate 22a, and does not include negative electrode active material Bed of material 22b.Other than negative electricity electrode current collector tab 22aa, anode active material layer 22b is also laminated to negative electrode substrate 22a Region.The edge of edge 22ab and 22ac formation negative electrode 22.

To make diaphragm 23 cover the entire negative electrode substrate 22a other than negative electricity electrode current collector tab 22aa, diaphragm 23 It is formed the width to have width of the direction greater than negative electrode substrate 22a along winding axis A.Respectively in a negative electricity Two diaphragms 23 are formed on wide major surfaces on the two sides of pole 22.Negative electricity electrode current collector tab 22aa two diaphragms 23 it Between pass through, and from 23 projection of diaphragm.In addition, a positive electrode 21 is arranged in an overlapping arrangement on diaphragm 23, so that when winding just When electrode 21, the inside of the diaphragm 23 of 22 inside of negative electrode is arranged in positive electrode 21 with being positioned adjacent to.Positive electrode 21 is formed as To have the width of width of the direction less than negative electrode substrate 22a along winding axis A, so that in addition to positive electricity electrode current collector pole Except ear 21aa, entire positive electrode substrate 21a is covered by negative electrode substrate 22a.For being made into the positive electricity Chong Die with diaphragm 23 The positive electrode substrate 21a of pole 21, other than positive electricity electrode current collector tab 21aa, entire positive electrode substrate 21a faces negative electrode Substrate 22a.Positive electricity electrode current collector tab 21aa is from 23 projection of diaphragm.

When overlapping each other before positive electrode 21 and negative electrode 22 are formed in winding positive electrode 21 and negative electrode 22, just Approximate middle part between electrode collector tab 21aa and negative electricity electrode current collector tab 22aa, in positive electrode substrate 21a Edge 2lab on form the notch part 21ad with rectangular shape, and formed on the edge 22ab of negative electrode substrate 22a Notch part 22ad with rectangular shape.Notch part 2lad extends to penetrate positive electrode substrate 21a and positive-active material Bed of material 21b.The gap with rectangular planar shape is formed in notch part 21ad.Notch part 22ad extends negative to penetrate Electrode basement 22a and anode active material layer 22b.The gap with rectangular planar shape is formed in notch part 22ad.No Notch part is formed on diaphragm 23.In this embodiment, notch part 2lad and 22ad is an example of concave portion, and The edge 22ab of the edge 2lab and negative electrode substrate 22a of positive electrode substrate 21a are the edge parts for being formed on concave portion The example divided.

The notch part 2lad being formed on positive electrode substrate 21a forms concave portion, is arranged from edge 2lab direction Edge 21ac on the side opposite with edge 21ab is retracted (indented).The recess being formed on negative electrode substrate 22a Part 22ad forms concave portion, contracts from edge 22ab towards the edge 22ac being arranged on the side opposite with edge 22ab Into.Notch part 2lad and notch part 22ad has same shape.However, being formed on positive electrode substrate 21a The size of notch part 2lad is set to be greater than the size for the notch part 22ad being formed on negative electrode substrate 22a.When making When positive electrode 21 and negative electrode 22 overlap each other, notch part 2lad and notch part 22ad are with wherein notch part 21ad and recessed The state that oral area divides 22ad to be substantially in alignment with each other overlaps each other.Further, it is expected that being formed in recessed on negative electrode substrate 22a Oral area divides 22ad to be located on the inside of the notch part 21ad being formed on positive electrode substrate 21a.As long as being formed in positive electrode substrate The size of notch part 21ad on 21a is set to be greater than the big of the notch part 22ad being formed on negative electrode substrate 22a It is small, it is not necessary to make notch part 21ad and notch part 22ad that there is same shape.However, for manufacture, preferably Be notch part 2lad and notch part 22ad have same shape.Winding positive electrode 21 and negative electrode 22 it Before, during preparing band-like positive electrode 21 and negative electrode 22, by being such as cut by laser to edge 21ab and 22ab application Or the notch of the punching press using mold, notch part 2lad and 22ad can be formed.There can be wide width by cutting Metal foil material etc. at the time of be cut into band-like positive electrode 21 and band-like negative electrode 22, notch portion can formed by notch Positive electricity electrode current collector tab 21aa and negative electricity electrode current collector tab 22aa is formed at the time of dividing 21ad and 22ad.

Notch part 21ad and 22ad, quilt are formed in a part of edge 2lab and a part of edge 22ab respectively It is arranged between positive electricity electrode current collector tab 21aa and negative electricity electrode current collector tab 22aa.The edge respectively notch part 2lad and 22ad The direction opposite with the projection direction of positive electricity electrode current collector tab 21aa and negative electricity electrode current collector tab 22aa from edge 2lab and 22ab retraction.In this embodiment, edge 2lab is present in notch part 2lad and 22ad and positive electricity electrode current collector tab 21aa Between, and edge 22ab is present between notch part 2lad and 22ad and negative electricity electrode current collector tab 22aa.

It is made into the above-mentioned positive electrode 21 to overlap each other, negative electrode 22 and diaphragm 23 around winding axis A along winding direction B It is spirally wound together, and therefore forms electrode assembly 20.In this embodiment, electrode assembly 20 is formed so as to edge It is approximately perpendicular to the flat elongated circular cross-sectional shape in the X/Y plane direction in the direction of winding axis A.However, electrode assembly 20 cross-sectional shape can be the shape other than elongated annular shape, and can be annular shape, ellipse, rectangle shape Shape or other polygonal shapes.

In order to describe the construction of energy storage device 100 referring also to Fig. 2 and Fig. 3, passing through winding positive electrode 21 and negative electricity In the electrode assembly 20 that pole 22 is formed, mutual entire positive electrode 21 and entire negative electrode are being stacked to along Y-axis line direction respectively Notch part 21ad and 22ad are formed on 22.In addition, all notch part 21ad and 22ad along Y-axis line direction it is substantially aligned at Row.Such notch part 21ad and 22ad forms hole section 27, is the concave portion with rectangular parallelepiped shape. Notch part 2lad and 22ad are arranged so as to form above-mentioned array at the time of processing positive electrode 21 and negative electrode 22.Setting exists Diaphragm 23 at the position of notch part 2lad and 22ad is not shown in figure 2 and figure 3.

In electrode assembly 20, it is stacked to mutual positive electrode 21, negative electrode 22 and the formation of diaphragm 23 and prolongs along winding direction B The wall ontology stretched.More specifically, wall ontology by with big width and even shape two flat wall part 20a and 20b and Two curved wall part 20c and 20d for bending to semi-circular shape are formed.Flat wall part 20a and 20b is positioned to phase each other It faces over the ground, and it is mediate to wind axis A.Flat wall part 20a and 20b is respectively adjacent to the long side wall of vessel 11 11c and 11e setting, and extend along long side wall 11c and 11e.Curved wall part 20c and 20d is respectively by the two of flat wall part 20a Two end sections of a end sections and flat wall part 20b are connected to each other.Curved wall part 20c and 20d be positioned to Just it faces relative to one another, and winds that axis A is mediate, and the short side wall 11d and 11f that are respectively adjacent to vessel 11 are fixed Position.

In electrode assembly 20, the direction along winding axis A is in the positive electrode 21 of stacked state and the side of negative electrode 22 The end sections 20e and 20f of edge formation electrode assembly 20.More specifically, in stacked state, the edge of positive electrode substrate 21a The edge 22ab of 2lab and negative electrode substrate 22a are arranged so as to form surface, and therefore form the end portion of electrode assembly 20 Divide 20e.In stacked state, the edge 22ac of the edge 2lac and negative electrode substrate 22a of positive electrode substrate 21a are arranged so as to Surface is formed, and therefore forms the end sections 20f of electrode assembly 20.End sections 20e and end sections 20f forms electrode group Two end surfaces in the direction of the edge winding axis A of part 20.

In electrode assembly 20, all positive electricity electrode current collector tab 21aa and all negative electricity electrode current collector tab 22aa are fixed Position is on the 20a of flat wall part, and from end sections 20e projection.On end sections 20e, positive electricity electrode current collector tab 21aa It is substantially arranged along Y-axis line direction from flat wall part 20a to flat wall part 20b in a row, therefore forms positive electricity electrode current collector pole Ear group 24.In the same manner, on end sections 20e, negative electricity electrode current collector tab 22aa is substantially along Y-axis line direction from flat wall Part 20a to flat wall part 20b alignment in a row, therefore forms negative electricity electrode current collector tab group 25.

Notch part 21ad and 22ad are positioned in positive electricity electrode current collector tab group 24 and negative electricity electrode current collector tab group 25 Between middle position far from positive electricity electrode current collector tab group 24 and negative electricity electrode current collector tab group 25, and from end sections 20e is retracted along the direction opposite with positive electricity electrode current collector tab group 24 and negative electricity electrode current collector tab group 25.In end sections 20e On, notch part 21ad and 22ad is substantially aligned in a row on flat wall part 20a and flat wall part 20b, therefore forms tool There is the hole section 27 of rectangular parallelepiped shape formed by concave portion, from flat wall part 20a to flat wall It is extended continuously on the region of part 20b.Hole section 27 from end sections 20e along and positive electricity electrode current collector tab group 24 and negative electricity The opposite direction retraction of electrode current collector tab group 25.Diaphragm 23 extends along hole section 27.

More micro-pore septums 23 have a large amount of hole.That is, diaphragm 23 allows gas to pass through it.Hole section wherein 27 are formed to allow gas by the way that in its situation, diaphragm 23 can have notch part, have and notch part The identical shape of 2lad and 22ad, and formed at the position substantially aligned with notch part 21ad and 22ad.In this case, The size for the notch part being formed on diaphragm 23 is set to be less than the size of notch part 2lad and 22ad.It is desirable that, When making diaphragm 23, positive electrode 21 and negative electrode 22 overlap each other, the notch part being formed on diaphragm 23 is located in notch portion Divide on the inside of 2lad and 22ad.The notch part being formed on diaphragm 23 can not have identical with notch part 21ad and 22ad Shape.However, the notch part preferably formed on diaphragm 23 has and notch part 2lad and 22ad for manufacture Identical shape.Even if not having the situation of the above-mentioned notch part corresponding to hole section 27 in wherein more micro-pore septums 23 In, also allow the gas of sufficient quantity to pass through hole section 27.

Hole section 27 by partially surrounding as follows: being approximately perpendicular to the flat bottom portion 27a of winding axis A；From bottom The side surface portion 27b that end sections of the part 27a on the side 20c of curved wall part are erect vertically towards end sections 20e；With And the side surface portion erect vertically from end sections of the bottom part 27a on the side 20d of curved wall part towards end sections 20e Divide 27c.Hole section 27 is along from bottom part 27a, to the direction of end sections 20e, edge is from winding axis A to flat wall part The direction of 20a, and along open from the direction of winding axis A to flat wall part 20b.That is, hole section 27 is being held At open end on the side 20e of portion part it is open and at the open end on the two sides of hole section 27 along 21 He of positive electrode Negative electrode 22 is stacked to mutual direction along it and opens.

The construction of positive electrode terminal 30 and negative electrode terminal 40 is more fully described referring also to Fig. 2 and Fig. 4.Fig. 4 is in Fig. 2 Shown in The lid component 12 decomposition perspective view.Positive electrode terminal 30 includes terminal body 31, upper insulating component 32 and lower insulation structure Part 33.Negative electrode terminal 40 includes terminal body 41, upper insulating component 42 and lower insulating component 43.Terminal body 31 and 41 is by all As the conductive material of metal is made.The rivet portion 31a and 41a with cylinder shape shape in a manner of projection respectively At the terminal body 31 and 41 in flat shape.Upper insulating component 32 and 42 and lower insulating component 33 and 43 are by such as resin Plate package made of material with electric insulation property.

Being formed in upper insulating component 32 and lower insulating component 33 respectively allows through-hole of the rivet portion 31a by it, and Being formed in upper insulating component 42 and lower insulating component 43 respectively allows through-hole of the rivet portion 41a by it.In The lid component 12 Middle formation respectively allows for rivet portion 31a and 41a through-hole 12b and 12c by it.

The rivet portion 31a formed in terminal body 31 the and rivet portion 41a formed in terminal body 41 difference It is configured to be connected electrically to positive electricity electrode current collector 50 and negative electricity electrode current collector 60.Positive electricity electrode current collector 50 and negative electricity electrode current collector 60 It is arranged on the side opposite with terminal body 31 and 41, and The lid component 12 is mediate.Positive electricity electrode current collector 50 is flat Surface member, conductive and rigidity.In a manner of identical with the positive electrode substrate 21a of electrode assembly 20, positive electrode current collection Body 50 is made of the metal of such as aluminum or aluminum alloy.Negative electricity electrode current collector 60 is plane institution movement, conductive and rigidity.With Mode identical with the negative electrode substrate 22a of electrode assembly 20, negative electricity electrode current collector 60 by such as copper or copper alloy made of metal At.Being formed in positive electricity electrode current collector 50 and negative electricity electrode current collector 60 respectively allows rivet portion 31a and 41a to pass through the logical of its Hole.

The rivet portion 31a being formed in the terminal body 31 of positive electrode terminal 30, which is formed through, is formed in insulation structure Through-hole in part 32, the through-hole 12b being formed in The lid component 12 and are formed in positive electricity at the through-hole being formed in lower insulating component 33 Through-hole (with the order) in electrode current collector 50, and later, these elements are held back together by rivet portion 31a riveting.Therefore, it uses Upper insulating component 32 between terminal body 31 and The lid component 12 and between positive electricity electrode current collector 50 and The lid component 12 Between lower insulating component 33, terminal body 31 and positive electricity electrode current collector 50 are installed in The lid component 12 and are fixed to The lid component 12.Here, terminal body 31 is physically and electrically connected to positive electricity electrode current collector 50.Upper insulating component 32 makes terminal body 31 It is electrically isolated from one another with The lid component 12, and lower insulating component 33 keeps The lid component 12 and positive electricity electrode current collector 50 electrically isolated from one another.

The rivet portion 41a being formed in the terminal body 41 of negative electrode terminal 40, which is formed through, is formed in insulation structure Through-hole in part 42, the through-hole 12c being formed in The lid component 12, the through-hole being formed in lower insulating component 43, and be formed in negative Through-hole (with the order) in electrode collector 60, and later, these elements are held back together by rivet portion 41a riveting.Therefore, With the upper insulating component 42 between terminal body 41 and The lid component 12 and between negative electricity electrode current collector 60 and The lid component Lower insulating component 43 between 12, terminal body 41 and negative electricity electrode current collector 60 are installed in The lid component 12 and are fixed to lid structure Part 12.Here, terminal body 41 is physically and electrically connected to negative electricity electrode current collector 60.Upper insulating component 42 makes terminal body 41 and The lid component 12 it is electrically isolated from one another, and lower insulating component 43 make The lid component 12 and negative electricity electrode current collector 60 each other it is electrical absolutely Edge.

Connection structure and negative electrode terminal between the terminal body 31 and positive electricity electrode current collector 50 of positive electrode terminal 30 Connection structure between 40 terminal body 41 and negative electricity electrode current collector 60 is not limited to rivet.As long as terminal body 31 and terminal sheet Body 41 is connect with positive electricity electrode current collector 50 and negative electricity electrode current collector 60 respectively, in wherein upper insulating component 32,12 and of The lid component Lower insulating component 33 between terminal body 31 and positive electricity electrode current collector 50 and upper insulating component 42, The lid component 12 and it is lower absolutely State of the edge component 43 between terminal body 41 and negative electricity electrode current collector 60, then any structure can be used as connection knot Structure.For example, screw bolt and nut can be used instead of rivet portion 31a and 41a.In addition, rivet portion 31a and 41a can distinguish It is welded to positive electricity electrode current collector 50 and negative electricity electrode current collector 60.

Positive electrode lead plate 51 and negative electrode lead plate 61 are for example formed by the board member for bending to U-shaped.Positive electrode lead Plate 51 is made of material identical with positive electricity electrode current collector 50.Negative electrode lead plate 61 is by material identical with negative electricity electrode current collector 60 Material is made.

Form the flat of two side sections of positive electrode lead plate 51 and U-shaped positive electrode lead plate 51 relatively facing with each other Face part links to the positive electricity electrode current collector 50 and positive electricity electrode current collector tab group 24 of electrode assembly 20 respectively.Negative electrode is formed to draw The planar section of two side sections of line plate 61 and U-shaped negative electrode lead plate 61 relatively facing with each other links to electrode respectively The negative electricity electrode current collector 60 and negative electricity electrode current collector tab group 25 of component 20.Such as ultrasonic bonding or resistance welding can be used Welding execute positive electrode lead plate 51 connection and negative electrode lead plate 61 connection.

With the construction, the terminal body 31 of positive electrode terminal 30 is physically and electrically connected to the positive electricity of electrode assembly 20 Pole 21, and positive electricity electrode current collector 50 and positive electrode lead plate 51 are mediate.41 physics of terminal body of negative electrode terminal 40 Ground and the negative electrode 22 for being electrically coupled to electrode assembly 20, and negative electricity electrode current collector 60 and negative electrode lead plate 61 are between it Between.

The construction that positive electrode terminal 30 and negative electrode terminal 40 are described with reference to Fig. 2 and Fig. 4, by molding by safety valve 70 with The lid component 12 is integrally formed.Safety valve 70 includes the weakened part formed by the thickness for reducing a part of The lid component 12 71.In this embodiment, when along the outer surface 12a of z axis direction observation The lid component 12, weakened part 71 is formed to have There is elongated annular flat shape.When with the internal pressure increase etc. in container 10, predetermined pressure acts on above-mentioned safety valve 70 When upper, weakened part 71 is destroyed, therefore forms the opening for playing pressure relief vent.Therefore, the pressure in container 10 is released To outside.Weakened part 71 is configured so on weakened part 71 also form groove part 72 by cutting, therefore promotes Destruction of the weakened part 71 at groove part 72.For example, groove part 72 has flat shape, wherein extending in different directions Two grooves be connected to the respective end of a groove, that is, the planar shaped that wherein two grooves with Y shape shape are connected to each other Shape.With the construction, promote to destroy weakened part 71 at the intersection of groove.By the shape, the shape that change weakened part 71 At the thickness of the component of weakened part, the shape of groove part, depth of groove part etc., release safety valve 70 can be can control Pressure.

Then, the positional relationship between The lid component 12 and electrode assembly 20 is described with reference to Fig. 5 and Fig. 6.Fig. 5 is institute in Fig. 1 The cross-sectional side view of the energy storage device 100 shown.That is, Fig. 5 is shown as seen along the direction V for being Y-axis line direction Along the long side wall 11c's and 11e for being parallel to vessel 11 at the center in the short side wall 11d and 11f of vessel 11 examined The view of the cross section of the energy storage device 100 of plane interception.Fig. 6 is that the energy of VI-VI interception along the line shown in Fig. 5 is deposited The cross-sectional side view of storage device 100.

Electrode assembly 20 is installed in The lid component 12, and wherein, is formed on the end sections of hole section 27 20e is arranged adjacent to the The lid component 12 of container 10.Hole section 27 is positioned to relative mode in face of safety valve 70.Such as Fig. 5 Shown in, along from positive electrode terminal 30 towards the direction of negative electrode terminal 40, that is, along X-axis line direction, side surface portion 27b and The width B1 of hole section 27 between side surface portion 27c is set to be greater than the width of the weakened part 71 of safety valve 70 B2.In addition, as shown in Figure 6, along from the flat wall part 20a of electrode assembly 20 towards the direction of flat wall part 20b, that is, The width of hole section 27 between Y-axis line direction, open end, that is, the width B3 of the bottom part 27a of hole section 27 It is set to be greater than the width B4 of the weakened part 71 of safety valve 70.In addition, the entire weakened part 71 of safety valve 70 faces Hole section 27.

In energy storage device 100 with above-mentioned construction, when due to by such as overcharging, hitting or gluing The decomposition of abnormality bring electrolyte solution generate gas, and due to the gas of generation, the internal pressure of container 10 When increasing so that safety valve 70 is released, there may be wherein flow out to outside since the flowing of gas passes through safety valve 70 suddenly Cause the situation that electrode assembly 20 is mobile towards The lid component 12.When mobile electrode assembly 20 and The lid component 12 collide, counterbore Part 27 ensures the space at the position that hole section 27 faces safety valve 70 with relative mode, so that in container 10 and electrode The space limited between component 20 and safety valve 70 is communicated with each other by above-mentioned space.Porous septum 23 has a large amount of hole, because This allows gas to pass through it, that is, porous septum 23 has permeability.Therefore, the gas in container 10 can pass through safety valve 70 flow out to outside.In addition, by adjusting the shapes and sizes of hole section 27, also hole section at the time of collision wherein In 27 situations deformed together with electrode assembly 20, the position of safety valve 70 can be faced with relative mode in wherein hole section 27 The place of setting ensures sufficient space.

Desirably the hole section 27 that above-mentioned advantageous effects can be obtained is positioned to relative mode in face of safety At least part of the weakened part 71 of valve 70.It faces to cut however, hole section 27 can be not arranged in wherein hole section 27 At the position of weak part 71.For example, even if when hole section 27 is arranged in along the direction along The lid component 12 adjacent to weakened part When at 71 position, it is also possible to so that the space being limited between container 10 and electrode assembly 20 passes through hole section 27 and safety Valve 70 is connected to.More specifically, hole section 27 and safety valve 70 pass through by positive electricity electrode current collector tab group 24, negative electricity electrode current collector Tab group 25 is connected to the gap that diaphragm 23 is formed.

The position of rigidity, hole section 27 based on 20 resistance to deformation of electrode assembly at the time of collision relative to safety valve 70 It sets, other sizes of hole section 27, the shape of hole section 27 etc., the slave end sections 20e of hole section 27 can be set To the depth (it is depth of the hole section 27 along the direction far from The lid component 12) of bottom part 27a, so that hole section 27 Above-mentioned advantageous effects can be obtained.For example, when the thickness of a collector tab is set to 0.008 mm or bigger, and formed When the quantity of the collector tab of collector tab group is set to 20 or bigger, it may be desirable to the slave end portion of hole section 27 The depth of 20e to bottom part 27a is divided to be set to 3 mm or more.

As it is described above, energy storage device 100 is a kind of energy storage device according to this embodiment, It include: the electrode assembly 20 formed by stacking positive electrode 21 and negative electrode 22；With container 10.Energy storage device 100 includes The safety valve 70 being formed in The lid component 12, the The lid component 12 form the wall part of container 10.In neighbouring The lid component 12, at least It is formed on the edge 2lab of positive electrode 21 and/or the edge 22ab of negative electrode 22 of one layer of positive electrode 21 or negative electrode 22 setting The notch part 2lad and/or notch part 22ad extended along the direction far from The lid component 12.

In above-mentioned construction, in the wherein electrode assembly 20 when the pressure increase in container 10 is released safety valve 70 In the situation mobile towards The lid component 12, notch part 2lad and 22ad can ensure between electrode assembly 20 and The lid component 12 Space.Accordingly, it is possible to prevent safety valve 70 from being closed by electrode assembly 20, and therefore, increased pressure can be discharged with stationary mode Power.

In energy storage device 100 according to this embodiment, notch part 2lad and/or notch part 22ad are at least A part faces safety valve 70.In above-mentioned construction, notch part 2lad and 22ad can ensure notch part 21ad wherein Space with 22ad with relative mode at the position of safety valve 70, and accordingly, it is possible to more easily prevent electrode assembly 20 Closed safe valve 70.

In energy storage device 100 according to this embodiment, electrode assembly 20 is constructed such that by winding positive electricity Pole 21 and negative electrode 22 form electrode assembly 20, and the winding axis A of electrode assembly 20 intersects with The lid component 12.With above-mentioned structure It makes, even if in there is the energy storage device 100 of lateral winding-type electrode assembly 20 that can output and input high electrical power, It may also ensure the space between electrode assembly 20 and The lid component 12 when electrode assembly 20 is mobile towards The lid component 12.

In energy storage device 100 according to this embodiment, multiple recesses are formed in positive electrode 21 and negative electrode 22 Part 21ad and 22ad, so that notch part 2lad and 22ad is stacked to mutual direction along it along positive electrode 21 and negative electrode 22 Arrangement is in a row.In above-mentioned construction, the space formed by multiple notch part 2lad and 22ad is along positive electrode 21 and negative electrode 22 Mutual direction is stacked to along it to overlap each other.Therefore, multiple notch part 21ad and 22ad increase is limited to electrode assembly Space between 20 and the The lid component 12 of container 10, and accordingly, it is possible to more easily prevent 20 closed safe valve 70 of electrode assembly.

In energy storage device 100 according to this embodiment, positive electrode 21 and negative electrode 22 are respectively provided with from edge The positive electricity electrode current collector tab 21aa and negative electricity electrode current collector tab 22aa of 2lab and 22ab projection are arranged adjacent to The lid component 12 At the position different from notch part 21ad and 22ad.In above-mentioned construction, notch part 21ad and 22ad are in a manner of being retracted The edge 22ab(of edge 2lab and negative electrode 22 from positive electrode 21 be respectively formed on it positive electricity electrode current collector tab 21aa and Negative electricity electrode current collector tab 22aa) it is formed along the direction of the The lid component 12 further from container 10.Therefore, even if working as electrode assembly 20 When being deformed towards The lid component 12 is mobile together with positive electricity electrode current collector tab 21aa and negative electricity electrode current collector tab 22aa, notch part 21ad and 22ad can also ensure that the space being limited between electrode assembly 20 and the The lid component 12 of container 10.

[remodeling]

About the remodeling of energy storage device 100 according to the embodiment, it can be considered that following construction.As shown in Figure 7, according to changing The energy storage device 200 of type is the energy storage device for including vertical winding-type electrode assembly.More specifically, energy stores fill The electrode assembly 220 for setting 200 faces appearance along the end sections 220e and 220f along the direction for winding axis A of electrode assembly 220 The direction of the short side wall 11d and 11f of device ontology 11 are arranged in vessel 11.That is, the winding axis of electrode assembly 220 Line A extends along the direction of the outer surface 12a along The lid component 12.Fig. 7 is substantially equal to the decomposition perspective view of Fig. 2, shows energy The construction of storage device 200 is measured, the energy storage device 200 is the energy storage device 100 of embodiment according to the present invention Remodeling.

Energy is described with reference to Fig. 8 in a manner of identical with the electrode assembly 20 of energy storage device 100 according to the embodiment The construction of storage device 200, electrode assembly 220 are formed so that the 221, negative electrodes 222 of a positive electrode to overlap each other It is spirally wound together into two diaphragms 23 along the winding direction B around winding axis A.Fig. 8 is shown in Fig. 7 with expansion mode Shown in electrode assembly 220 a part perspective view.

The positive electrode substrate 221a of positive electrode 221 does not include positive electricity electrode current collector tab.Anode active material layer 21b tegillum It is depressed into substantially entire positive electrode substrate 221a.However, anode active material layer 21b is not laminated to the non-coated part of positive electrode 221ad is the band for an adjacent edges being arranged in two extendd in the longitudinal direction the edge of positive electrode substrate 221a Shape region.

Multiple positive electrode opening portion 221c with rectangular shape are formed in positive electrode 221, so that positive electrode is open Part 221c penetrates positive electrode substrate 221a and anode active material layer 21b.Multiple positive electrode opening portion 221c are along positive electrode 221 longitudinal direction is formed in positive electrode 221 with interval mode.In addition, multiple positive electrode opening portion 221c are located in just Approximate center of the edge of pole active material layer 21b perpendicular to the lateral of the longitudinal direction of rectangular strip shape positive electrode 221.Just Electrode opening part 221c can be formed such that be cut by laser etc. and cut out from positive electrode substrate 221a with rectangular shape Part, or stamp out the part with rectangular shape from positive electrode substrate 221a using mold etc..Positive electrode opening portion 221c is arranged on positive electrode 221, so that for around each circle one positive electrode of formation of winding axis A on positive electrode 221 Opening portion 221c.In addition, stacking direction of multiple positive electrode opening portion 221c after wrapping along positive electrode 221 is substantially right It is neat in a row.

The negative electrode substrate 222a of negative electrode 222 does not include negative electricity electrode current collector tab.Anode active material layer 22b tegillum It is depressed into substantially entire negative electrode substrate 222a.However, anode active material layer 22b is not laminated to the non-coated part of negative electrode 222ad is the band for an adjacent edges being arranged in two extendd in the longitudinal direction the edge of negative electrode substrate 222a Shape region.In addition, when making positive electrode 221 and negative electrode 222 overlaps each other to wind, the non-coated part 222ad of negative electrode It is located on the side opposite with the non-coated part 221ad of positive electrode.

Multiple negative electrode opening portion 222c with rectangular shape are formed in negative electrode 222, so that negative electrode is open Part 222c penetrates negative electrode substrate 222a and anode active material layer 22b.Negative electrode opening portion 222c has and positive electrode The identical shape of opening portion 221c.However, the size of negative electrode opening portion 222c is set to be less than positive electrode opening portion Divide the size of 221c.Negative electrode opening portion 222c can not have shape identical with positive electrode opening portion 221c.However, For manufacture, preferably negative electrode opening portion 222c has shape identical with positive electrode opening portion 221c.It is multiple Negative electrode opening portion 222c is formed in negative electrode 222 along the longitudinal direction of negative electrode 222 with interval mode.In addition, multiple Negative electrode opening portion 222c is located in longitudinal direction side of the edge perpendicular to rectangular strip shape negative electrode 222 of anode active material layer 22b To lateral approximate center.Negative electrode opening portion 222c, which can be formed so that, to be cut by laser etc. from negative electricity Pole substrate 222a cuts out the part with rectangular shape, or is stamped out from negative electrode substrate 222a with rectangle using mold etc. The part of shape.Negative electrode opening portion 222c is arranged on negative electrode 222, so that for around winding axis on negative electrode 222 Each circle of line A forms a negative electrode opening portion 222c.In addition, multiple negative electrode opening portion 222c are formed so that After winding, negative electrode opening portion 222c is substantially stacked to mutual direction cloth along it along positive electrode 221 and negative electrode 222 The row of being set to, and negative electrode opening portion 222c is also substantially aligned in a row along above-mentioned stacking direction with positive electrode opening portion 221c. That is, forming corresponding negative electricity on negative electrode 222 when making positive electrode 221 and negative electrode 222 overlaps each other to wind Pole opening portion 222c, so as to Chong Die with corresponding positive electrode opening portion 221c in aligned fashion.It is desirable here that be negative electrode Opening portion 222c is located on the inside of the 221c of positive electrode opening portion.

Diaphragm 23 is formed on the major surfaces formed on the two sides of negative electrode 222 to cover entire negative electrode 222, is removed Except negative electrode non-coated part 222ad.The non-coated part 222ad projection of negative electrode, while being worn between two diaphragms 23 It crosses.Entire positive electrode 221 is covered by negative electrode 222 and diaphragm 23, other than the non-coated part 221ad of positive electrode.It is made into The entire anode active material layer 21b of the positive electrode 221 Chong Die with negative electrode 222 faces anode active material layer 22b.Positive electrode Non-coated part 221ad is on the side opposite with the non-coated part 222ad of negative electrode from 23 projection of diaphragm.Positive electrode 221 is set It is set to so that positive electrode 221 is positioned adjacent to 23 inside of diaphragm of the inside setting of negative electrode 222 at the time of winding.

In the electrode assembly 220 formed after wrapping, positive electrode opening portion 221c and negative electrode opening portion 222c It is located at the curved wall part 220c of electrode assembly 220.More specifically, positive electrode opening portion 221c and negative electrode opening portion Central part and negative electrode opening portion 222c the edge winding for dividing 222c to be located so that positive electrode opening 221c along winding direction B The central part of direction B is located at the projection marginal end portion 220ca of curved wall part 220c.The projection of curved wall part 220c Marginal end portion 220ca is the marginal end portion of curved wall part 220c, and mainly towards outer lateral edge z axis direction, (it is electrode group The flat wall part 220a of part 220 and the lateral of 220b) projection, and extend along winding axis A.That is, projection side Acies portion 220ca is located at the top section of the lateral along flat wall part 220a and 220b of curved wall part 220c The a part at place, and when electrode assembly 220 is received in container 10, it is positioned closest to The lid component 12.Positive electrode opening Part 221c and negative electrode opening portion 222c forms hole section 227 in the 220c of curved wall part, wherein hole section 227 be concave portion, has from projection marginal end portion 220ca and extends to winding axis A, that is, to curved wall part 220d's Semi-cylindrical form.Diaphragm 23 extends in hole section 227.

Diaphragm 23, which can have, has shape identical with positive electrode opening portion 221c and negative electrode opening portion 222c And the opening portion substantially aligned with positive electrode opening portion 221c and negative electrode opening portion 222c in position.In the situation In, the size of the opening portion formed in diaphragm 23 is set to be less than the size and negative electrode of positive electrode opening portion 221c The size of opening portion 222c.It is desirable that, being formed in when making diaphragm 23, positive electrode 221 and negative electrode 222 overlap each other Opening portion in diaphragm 23 is located on the inside of positive electrode opening portion 221c and negative electrode opening portion 222c.It is formed in diaphragm Opening portion in 23 can not have shape identical with positive electrode opening portion 221c and negative electrode opening portion 222c.So And for manufacture, it is preferred that the opening portion being formed in diaphragm 23 has and positive electrode opening portion 221c and negative electricity The identical shape of pole opening portion 222c.Even if not having above-mentioned opening portion in the diaphragm 23 wherein with large number of orifices, (its is right Should extend in hole section 227 and in hole section 227) situation in, also allow sufficient quantity gas pass through hole section 227 inside.

Hole section 227 by partially surrounding as follows: the flat bottom portion 227a on the winding side axis A；And the bottom of from The side surface portion that two ends of portion part 227a are erect along the direction of winding axis A towards projection marginal end portion 220ca vertically Divide 227b and 227c.Hole section 227 is along from bottom part 227a to the direction of projection marginal end portion 220ca, along from flat wall Part 220a is to the direction of flat wall part 220b, and along opening from flat wall part 220b to the direction of flat wall part 220a It puts.That is, hole section 227 is stacked to mutual direction from bottom part along it along positive electrode 221 and negative electrode 222 227a is open.

In above-mentioned electrode assembly 220, positive electrode opening portion 221c is located in each circle of positive electrode 221, so that The central part along winding direction B of positive electrode opening portion 221c is located at the projection marginal end portion 221d of positive electrode 221, It extends mainly from winding axis A towards projection marginal end portion 220ca projection along the direction of winding axis A.Positive electrode opening Part 221c forms concave portion, is retracted from the projection marginal end portion 221d in positive electrode 221 towards winding axis A.With phase Same mode, negative electrode opening portion 222c are also positioned in each circle of negative electrode 222, so that negative electrode opening portion 222c Central part along winding direction B is located at the projection marginal end portion 222d of negative electrode 222, mainly from winding axis A court Extend to projection marginal end portion 220ca projection, and along the direction of winding axis A.Negative electrode opening portion 222c forms concave portion Point, it is retracted from the projection marginal end portion 221d in negative electrode 222 towards winding axis A.The above-mentioned projection edge of positive electrode 221 The above-mentioned projection marginal end portion 222d of end 221d and negative electrode 222 is an example of the marginal portion of electrode plate, and positive electricity Pole opening portion 221c and negative electrode opening portion 222c is an example of concave portion.

In the electrode assembly 220 formed after wrapping, the non-coated part 22lad of the positive electrode of winding is along winding axis A The direction non-coated part 222ad of negative electrode that forms an end sections 220e of electrode assembly 220, and wind along winding axis The direction of line A forms the other end part 220f of electrode assembly 220.

And in the remodeling, electrode assembly 220 is formed so as to elongate circular cross-sectional shape.However, The cross-sectional shape of electrode assembly 220 can be the shape other than elongated annular shape, and can be circular shape, ellipse Type, rectangular shape or other polygonal shapes.

Electrode assembly 220 is described with reference to Fig. 7, the non-coated part 22lad of the positive electrode of electrode assembly 220 passes through positive electrode collection Electric body 250 is electrically coupled to the positive electrode terminal 30 of the The lid component 12 of container 10, and is fixed to The lid component 12 simultaneously.Electrode The non-coated part 222ad of the negative electrode of component 220 is electrically coupled to the negative electrode of The lid component 12 by negative electricity electrode current collector 260 Terminal 40, and it is fixed to The lid component 12 simultaneously.Positive electricity electrode current collector 250 is made of material identical with positive electrode substrate 221a. Negative electricity electrode current collector 260 is made of material identical with negative electrode substrate 222a.

Using the rivet portion 31a in the terminal body 31 for being formed in positive electrode terminal 30 by riveting positive electrode current collection Body 250 is fixed to terminal body 31.In addition, two Leg portion 250a included by positive electricity electrode current collector 250 are assembled to just The non-coated part 221ad(of electrode it is bundled along stacking direction) so that Leg portion 250a is from the non-coated part of positive electrode Clamp the non-coated part 221ad of positive electrode in the two sides of 221ad.To link to positive electrode non-by welding etc. by two Leg portion 250a Coated portion 22lad.Upper insulating component 32 keeps terminal body 31 and The lid component 12 electrically isolated from one another, and lower insulating component 33 makes The lid component 12 and positive electricity electrode current collector 250 are electrically isolated from one another.

Using the rivet portion 41a in the terminal body 41 for being formed in negative electrode terminal 40 by riveting negative electrode current collection Body 260 is fixed to terminal body 41.In addition, two Leg portion 260a included by negative electricity electrode current collector 260 be assembled to it is negative The non-coated part 222ad(of electrode it is bundled along stacking direction) so that Leg portion 260a is from the non-coated part of negative electrode Clamp the non-coated part 222ad of negative electrode in the two sides of 222ad.To link to negative electrode non-by welding etc. by two Leg portion 260a Coated portion 222ad.Upper insulating component 42 keeps terminal body 41 and The lid component 12 electrically isolated from one another, and lower insulating component 43 makes The lid component 12 and negative electricity electrode current collector 260 are electrically isolated from one another.

Electrode assembly 220 is mounted in The lid component 12, so that being formed on the projection marginal end portion of hole section 227 220ca is arranged adjacent to The lid component 12.That is, projection marginal end portion 220ca is positioned closest in electrode assembly 220 The lid component 12.Hole section 227 is positioned to relative mode in face of safety valve 70.Along from positive electrode terminal 30 towards negative electricity The direction of extreme son 40, that is, the hole section 227 along X-axis line direction, between side surface portion 227b and side surface portion 227c Width be set to be greater than safety valve 70 weakened part 71 width.In addition, along from the flat wall part of electrode assembly 220 220a is towards the direction of flat wall part 220b, that is, the width of the hole section 227 between Y-axis line direction, open end, That is, the width of bottom part 227a is set to be greater than the width of the weakened part 71 of safety valve 70.In addition, safety valve 70 is whole A weakened part 71 faces hole section 227.

In energy storage device 200 with above-mentioned construction, wherein container 10 internal pressure increase at the time of In the situation for discharging safety valve 70, even if when in the situation that electrode assembly 220 is mobile and collides with The lid component 12, hole section 227 also ensure that the space at the position that hole section 227 faces safety valve 70 with relative mode.Above-mentioned space and it is limited to appearance Space connection between device 10 and electrode assembly 220.Therefore, the gas in container 10 can be flowed out to outer by safety valve 70 Side.In addition, by adjusting the shapes and sizes of hole section 227, also hole section 227 and electrode at the time of collision wherein In the situation that component 220 deforms together, hole section 227 can ensure that hole section 227 faces to pacify wherein with relative mode Sufficient space at the position of full valve 70.

Energy storage device 200 other construction and mode of operation substantially with energy storage device 100 according to the embodiment Corresponding construction it is identical with mode of operation, and therefore, the description of omission such construct and mode of operation.In addition, as described above, root According to the energy storage device 200 of remodeling 1, may obtain roughly the same with energy storage device 100 according to the embodiment advantageous Effect.

[other remodeling]

Although foregoing have described the energy stores of energy storage device according to the embodiment and remodeling according to the present invention dresses It sets, but the present invention is not limited to this embodiment and remodeling.That is, should explain, current the disclosed embodiments and Remodeling is provided for illustration purposes only in all respects, and does not limit the present invention.The scope of the present invention is not referred to by foregoing description It is fixed, but specified by claim, and be contemplated that all remodeling in the meaning and range for falling in and being equivalent to claim It is included in the scope of the present invention.

In the energy storage device according to embodiment and remodeling, electrode assembly is wound around type electrode assembly, by twining It is formed around mutual positive electrode, negative electrode and diaphragm is stacked to.However, electrode assembly is not limited to this winding-type electrode group Part.Electrode assembly can be stacked electrode assembly, by by a large amount of positive electrode, a large amount of negative electrode and a large amount of diaphragm It is stacked to each other and is formed.Alternatively, electrode assembly can be Z-type electrode assembly, by making to be stacked to mutual positive electricity Pole, negative electrode and diaphragm flexes are repeatedly formed.

In the energy storage device according to embodiment and remodeling, the hole section of electrode assembly has six face of rectangular parallel Shape.However, the shape of hole section is not limited to rectangular parallelepiped shape.Hole section can have cylindricality, such as Semi-cylindrical, semiellipse cylindricality, triangle cylindricality or Polygonal column shape, wherein cross-sectional shape is not along at two of electrode assembly The direction extended between flat wall portion point changes.Here, for example, energy storage device according to the embodiment electrode assembly In, the multiple notch parts formed in positive electrode and negative electrode have same shape, and thereby, it is possible to easily process positive electricity Pole substrate and negative electrode substrate.Alternatively, hole section can have the shape of such as hemispherical or semielliptical shape, In, cross-sectional shape changes along the direction extended between two flat wall portions of electrode assembly point.

In the electrode assembly 20 of energy storage device 100 according to the embodiment, far from positive electricity electrode current collector tab group 24 Hole section 27 is set with negative electricity electrode current collector tab group 25.That is, the edge 21ab and negative electrode 22 of positive electrode 21 Edge 22ab is between hole section 227 and positive electricity electrode current collector tab group 24, and between hole section 227 and negative electrode Between collector tab group 25.However, neighbouring positive electricity electrode current collector tab group 24 and negative electrode can be set into hole section 27 Any one of collector tab group 25, without make edge 21ab between hole section 27 and positive electricity electrode current collector tab group 24 it Between, or do not make edge 22ab between hole section 27 and negative electricity electrode current collector tab group 25.

In the electrode assembly 220 according to the energy storage device 200 of remodeling, hole section 227 has flat bottom portion Divide 227a.However, electrode assembly 220 is not limited to this construction.For example, the positive electrode opening portion being formed on positive electrode 221 221c and the negative electrode opening portion 222c being formed on negative electrode 222 can have hole section, wherein the bottom of hole section The center of portion part is retracted.

The electrode group of electrode assembly in energy storage device according to the embodiment and the energy storage device according to remodeling In part, at the part for corresponding to hole section, notch part or positive electricity are formed in all layers of positive electrode for stacking stratification Pole opening portion.In addition, forming recess in all layers of negative electrode for stacking stratification at the part for corresponding to hole section Part or negative electrode opening portion.However, the present invention is not limited to this constructions.Any that can only in positive electrode and negative electrode Notch part or opening portion are formed on person.Notch part or opening are wherein being formed in any one of positive electrode and negative electrode Partial situation and in the two kinds of feelings of situation for wherein forming notch part or opening portion in both positive electrode and negative electrode In shape, notch part is formed in at least one layer of positive electrode for stacking stratification or positive electrode opening portion is sufficient, or Notch part is formed in at least one layer of negative electrode for stacking stratification or negative electrode opening portion is sufficient.

Energy storage device according to the embodiment and according to the energy storage device of remodeling include an electrode assembly 20.So And each energy storage device may include two or more electrode assemblies.

In energy storage device 100 according to the embodiment, electrode assembly 20 is configured so that positive electricity electrode current collector tab Group 24 and negative electricity electrode current collector tab group 25 are formed on end sections 20e.However, the present invention is not limited to this constructions.Electrode Component, which is configured so to electrode assembly, both not to have been had positive electrode collector tab group 24 or had not had negative electricity electrode current collector tab Group 25, and it is non-coated to form band-like positive electrode on two end sections in the direction of the edge winding axis A of electrode assembly respectively Part and the non-coated part of band-like negative electrode, such as in the situation according to the electrode assembly 220 of the energy storage device 200 of remodeling Like that.In this case, the non-coated part of positive electrode and the non-coated part of negative electrode are connected respectively to positive electricity electrode current collector and bear Electrode collector.

In the energy storage device 200 according to remodeling, electrode assembly 220 is configured to through the non-coated portion of positive electrode The 221ad and non-coated part 222ad of negative electrode is divided to be connected to positive electricity electrode current collector 250 and negative electricity electrode current collector 260.However, this Invention is not limited to this construction.It includes respectively in the non-coated part of positive electrode that energy storage device, which is configured so to electrode assembly, It in the positive electrode substrate 221a of positive electrode 221 and is born at the position of 221ad and at the position of the non-coated part 222ad of negative electrode The tab formed in a manner of projection as its integral part on the negative electrode substrate 222a of electrode 222.In addition, positive electricity electrode current collector 250 and negative electricity electrode current collector 260 may be coupled to tab.

In the energy storage device 200 according to remodeling, projection marginal end of the electrode assembly 220 in curved wall part 220c There is hole section 227 at portion 220ca.However, the present invention is not limited to this constructions.Electrode assembly 220 can have in electrode Hole section at the end sections 220e or 220f in the direction of the edge winding axis A of component 220.In this case, electrode group The hole section of part 220 can have the hole section 27 with the electrode assembly 20 of energy storage device 100 according to the embodiment Roughly the same construction, and the method roughly the same with the method for being used to form hole section 27 can be used and formed.Moreover, closing , with the electrode assembly 220 of hole section, extend just from the The lid component 12 of container 10 at end sections 220e or 220f Electrode collector 250 and negative electricity electrode current collector 260 are connected respectively to the non-coated part 221ad of positive electrode and the non-coated portion of negative electrode Divide 222ad.Safety valve is formed on the short side wall 11d or 11f of the vessel 11 of container 10, counterbore is faced with relative mode Part.Further, the safety valve being formed on short side wall l1d or 11f can be set wherein safety valve with relative mode At the position of hole section.

According in the electrode assembly of embodiment and the energy storage device of remodeling, diaphragm 23 both do not had notch part or Extend without opening portion, and along hole section.However, the present invention is not limited to this constructions.Can also in diaphragm 23 shape At the notch part or opening for being substantially equal to the notch part or opening portion that are formed in positive electrode substrate and negative electrode substrate Part.

In addition, being also included in the scope of the present invention by the construction that any combination embodiment and remodeling are formed.This hair It is bright to realize above-mentioned energy storage device, and can be realized the energy including one or more energy storage devices Store equipment.

Industrial feasibility

The present invention is suitable for the energy storage device of lithium ion secondary battery etc..

Claims

1. a kind of energy storage device, comprising:

By the way that electrode plate to be stacked to the electrode assembly formed each other；And

Container, wherein

Safety valve is formed on the wall of a container part, and,

It is formed on the marginal portion of at least one layer of electrode plate of neighbouring wall part setting along the separate wall part The concave portion that direction extends.

2. energy storage device according to claim 1, wherein

At least part of the concave portion is configured to relative mode in face of the safety valve.

3. energy storage device according to claim 1 or 2, wherein

The electrode assembly is configured so as to form the electrode assembly by winding the electrode plate, and,

The winding axis of the electrode assembly intersects with the wall part.

4. energy storage device according to any one of claims 1 to 3, wherein

Multiple concave portions are formed on the electrode plate, so that the concave portion is arranged along the stacking direction of the electrode plate In a row.

5. energy storage device according to any one of claims 1 to 4, wherein

The electrode plate, which has, to be set up separately at the position for being different from the concave portion from the neighbouring wall portion of the electrode plate The tab for the marginal portion projection set.