JP2008041489A - Lithium ion electricity storage element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve productivity of a lithium ion electricity storage element, and to improve reliability of a product, in a lithium ion electricity storage element having a structure composed by storing a spirally-rolled tubular electrode body in a bottomed tubular metallic negative electrode can along with a nonaqueous electrolyte. <P>SOLUTION: Lithium 41 for preliminarily storing lithium ions in a negative electrode 231 is arranged in an inner bottom part of the bottomed tubular metallic negative electrode can 10 along with an electrically insulating spacer member 50 having openings 51 piercing in the thickness direction, and the lithium 41 is short-circuited to the negative electrode 231. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lithium ion storage element, and in particular, using a positive electrode capable of occluding / releasing and adsorbing / desorbing anions, a negative electrode capable of occluding / releasing lithium ions, and a non-aqueous electrolyte containing a lithium salt. The present invention relates to a device that performs a reversible operation of charge / discharge.

  In recent years, the amount of data handled by electronic devices has increased dramatically due to the high performance of electronic devices. With this, there is a need for a small uninterruptible power supply to protect the data from power outages. It is increasing.

  As the uninterruptible power supply, a device using a lead storage battery has been conventionally provided. However, the lead storage battery has a low energy density, and only a large-capacity power supply device has been put into practical use. For this reason, the uninterruptible power supply using a lead storage battery has been commercialized only for large external use.

  Uninterruptible power supply units that can be built into devices have been commercialized due to the advent of high-energy density lithium-ion secondary batteries.

  A lithium ion secondary battery is a positive electrode using a composite oxide of lithium and other transition metals such as cobalt (for example, lithium cobaltate), a negative electrode capable of occluding and releasing lithium ions, and a non-aqueous electrolysis containing a lithium salt. The reversible operation of charging / discharging is performed by the exchange of lithium ions between the positive electrode and the negative electrode, which is performed using an electrolyte solution.

  However, the lithium ion secondary battery has a property of deteriorating as charging and discharging are repeated, and the number of cycles that can be charged and discharged is limited. That is, there is a problem that the charge / discharge cycle characteristics are not good. This is also a problem common to secondary batteries including lead-acid batteries, etc., but this makes it possible to perform maintenance such as inspection and replacement of secondary batteries in an uninterruptible power supply system using this type of secondary battery. It was necessary to do it regularly.

  In recent years, wind power generation and solar cells have attracted attention as clean energy with a low environmental impact, but the power supplied from these is unstable due to natural conditions such as wind and sunshine, so it remains as it is. Then, the utility value as electric power is low.

  If this unstable electric power can be stored once and released at any time as needed, it is possible to obtain electric power with high utility value even with the same amount of energy. For this purpose, power storage means capable of storing electric power so that it can be released at any time is required.

  An electrical double layer capacitor that has good charge / discharge cycle characteristics and does not require periodic maintenance is suitable for the power storage means, not the lithium ion secondary battery that places a heavy maintenance burden. However, although an electric double layer capacitor can have a very large capacity as a capacitor, the electric capacity that can be charged and discharged is considerably inferior to the lithium ion secondary battery.

  Therefore, a lithium ion storage element having a configuration in which an electric double layer capacitor and a lithium ion secondary battery are compromised has been proposed. This power storage element is configured using a positive electrode capable of occluding and releasing anions, a negative electrode capable of occluding and releasing lithium ions, and a non-aqueous electrolyte containing a lithium salt (see Patent Documents 1 and 2). .

  In the lithium ion secondary battery, a composite oxide containing lithium is used for the positive electrode. In the lithium ion storage element, a carbon material such as graphite or activated carbon is used for the positive electrode. And the reversible operation of charging / discharging is performed by occlusion / release of the anion in the positive electrode and occlusion / release of lithium ion in the negative electrode.

  This lithium ion storage element has such a property that the lithium ion secondary battery and the electric double layer capacitor have both advantages. That is, the charge / discharge cycle characteristics are superior to each stage as compared with the lithium ion secondary battery, and the charge / discharge capacity (capacity capable of being charged / discharged) is greater than each stage of the electric double layer capacitor.

  This lithium-ion storage element can be suitably used as a high-performance secondary battery, but if used in the uninterruptible power supply system, it is possible to realize a maintenance-free uninterruptible power supply system as well as downsizing and high performance. Can do.

  In the lithium ion storage element, in order to perform a charge / discharge reversible process with high efficiency, lithium ions are previously stored in the negative electrode. So-called pre-occlusion (pre-doping) is performed.

  This pre-occlusion can be performed by placing lithium metal in an element container in which an electrode body composed of a positive electrode, a negative electrode, and a separator is accommodated together with an electrolyte, and short-circuiting it with the negative electrode. The lithium metal short-circuited with the negative electrode elutes as lithium ions in the non-aqueous electrolyte, moves to the negative electrode, and is occluded.

As a constituent means for performing this pre-occlusion, conventionally, it has been proposed to attach a lithium metal foil to a part of the negative electrode current collector, or to arrange lithium metal on the inner bottom surface of the negative electrode can. .
JP-A-2005-19762 JP2002-305034

  The inventors have performed the above-described pre-occlusion in a lithium ion storage element having a configuration in which a cylindrical electrode body wound in a spiral shape is accommodated in a bottomed cylindrical metal negative electrode can together with a non-aqueous electrolyte. It was considered to make it.

  In this type of lithium ion storage element, as means for pre-occlusion, (1) a structure in which a lithium metal foil is attached to a part of the negative electrode current collector, and (2) lithium metal on the inner bottom surface of the negative electrode can A configuration to be arranged is conceivable.

  In the case of (1), lithium ions eluted from the lithium metal into the non-aqueous electrolyte diffuse while moving along the spirally wound separator. As a result, the storage state varies. That is, there arises a problem that the negative electrode is not uniformly occluded.

  Lithium metal is thinly spread and attached to the surface of the current collector in a foil shape, but this form of lithium metal is extremely reactive and reacts violently even by touching slight moisture in the air. Resulting in.

  The current collector is loaded into the negative electrode can after a long process time and line, such as a process for producing a spirally wound electrode body and a conductor lead connection process after lithium metal is attached. There is a high risk that lithium metal will react and deteriorate during this process. In order to avoid this, it is necessary to perform the entire series of processes under strict atmosphere control. For this reason, the problem that productivity will be inhibited greatly arises.

  In the case of (2), the lithium metal may be disposed on the inner bottom surface of the negative electrode can in the step immediately before loading the already produced electrode body into the negative electrode can. The negative electrode can can be hermetically sealed by injecting a non-aqueous electrolyte on site. Therefore, the handling of lithium metal can be greatly simplified as compared with the case (1), and productivity can be improved.

  However, after the lithium metal arranged on the inner bottom surface of the negative electrode can elutes into the non-aqueous electrolyte, voids are generated on the inner bottom surface of the negative electrode can. For this reason, loosening that allows the electrode body to move in the axial direction in the negative electrode can occurs, and when the storage element receives an impact such as dropping, the electrode body falls into the gap, and further, the electrode body The end portion is crushed and the positive electrode current collector may come into contact with the metal negative electrode can. If the positive electrode current collector comes into contact with the negative electrode can, an internal short circuit occurs, the battery becomes unusable, and gas is generated, which may cause damage or rupture of the battery.

  As described above, the above means (1) and (2) have the problem of a decrease in productivity due to handling highly reactive lithium metal and a decrease in reliability due to destabilization of the accommodation state of the electrode body. was there.

  The present invention has been made in view of the above problems, and its purpose is to form a cylindrical electrode body wound in a spiral shape into a bottomed cylindrical metal negative electrode can together with a non-aqueous electrolyte. In the lithium ion storage element having the housed configuration, the productivity is increased and the reliability of the product is increased.

  Other objects and configurations of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  The solution provided by the present invention is as follows.

(1) A sheet-like positive electrode portion comprising a positive electrode capable of occluding and releasing anions and a current collector, and a sheet-like negative electrode portion comprising a negative electrode capable of occluding and releasing lithium ions and a current collector, A cylindrical electrode body wound in a spiral shape with a separator interposed therebetween, a non-aqueous electrolyte solution in which lithium salt is dissolved, and the electrode body are coaxially accommodated together with the non-aqueous electrolyte solution A lithium ion storage element comprising a bottomed cylindrical metal negative electrode can and a sealing portion for hermetically sealing the opening of the negative electrode can, wherein the negative electrode preliminarily stores lithium ions, Lithium comprising an electrically insulating spacer member having an opening extending in the thickness direction, wherein the lithium metal is disposed on the inner bottom of the negative electrode can together with the spacer member, and the lithium metal is short-circuited with the negative electrode On the storage element.
(2) In the above means (1), the lithium metal is disposed between the opening of the spacer member and between the spacer member and the bottom surface of the negative electrode can.
(3) In the above means (1), the lithium metal is disposed between the opening of the spacer member and between the spacer member and the electrode body.

  (4) In any one of the means (1) to (3), the spacer member and the lithium metal form a through hole at a position corresponding to the center hole of the electrode body, and inside the through hole, A lithium ion storage element, wherein a conductive lead electrically connected to the negative electrode and the lithium metal is welded to a bottom surface of the negative electrode can.

The present invention also provides, for example, the following means other than those described in the claims.
(5) The lithium ion storage element according to any one of the above means (1) to (4), wherein each of the positive electrode and negative electrode current collectors is a metal foil.
(6) In any one of the above means (1) to (5), the positive electrode and the negative electrode are each made of a carbon material, the positive electrode is made of a graphite material, and the negative electrode is made of a non-graphitizable carbonaceous material. A lithium ion energy storage device characterized by the above.

  In a lithium ion storage element having a configuration in which a cylindrical electrode body wound in a spiral shape is housed in a bottomed cylindrical metal negative electrode can together with a non-aqueous electrolyte, the productivity is improved and the reliability of the product is improved. Can be increased.

  Operations / effects other than those described above will be apparent from the description of the present specification and the accompanying drawings.

  FIG. 1 is a cross-sectional view showing an embodiment of a lithium ion storage element to which the technology of the present invention is applied. The lithium ion storage element shown in the figure is a storage element that can also be used as a lithium ion secondary battery. First, a cylindrical electrode body 20 wound in a spiral shape is used as a bottomed cylindrical metal negative electrode. It has the structure accommodated in the can 10 with the non-aqueous electrolyte (illustration omitted).

  In the figure, a negative electrode can 10 corresponds to a battery can and is manufactured by a deep drawing press such as a nickel-plated steel plate. The electrode body 20 is manufactured by forming the positive electrode portion 21 and the negative electrode portion 23 in a sheet shape and winding the electrode portions 21 and 23 in a spiral shape with the separator 22 interposed therebetween.

  The positive electrode portion 21 is formed in a sheet shape by applying a positive electrode 211 made of a carbon material capable of occluding and releasing anions to both surfaces of a current collector 212 of a metal foil (Al) by coating or the like. Has been.

  The negative electrode part 23 has a negative electrode 231 capable of occluding and releasing lithium ions attached to both surfaces of a metal foil (Cu) current collector 232 in a layered manner by coating or the like, and is formed in a sheet shape as a whole.

  The shape of the current collectors 212 and 232 is not particularly limited as long as they are good conductors that are inert to the non-aqueous electrolyte. For example, a metal net can be used, but the winding density and current collection of the electrode body 20 can be used. When electric performance etc. are considered, use of metal foil is particularly preferable. As for the material, a combination in which the positive electrode current collector 212 is aluminum (Al) and the negative electrode current collector 232 is copper (Cu) is preferable.

  The positive electrode 211 occludes anions in the electrolyte during charging and releases them during discharging. The negative electrode 231 occludes lithium ions (cations) in the electrolyte during charging and releases them during discharging. The reversible operation of charging / discharging is performed by reversible occlusion / release of the anion and lithium ion.

  As the material of the positive electrode 211 and the negative electrode 231, a carbon material is suitable. In particular, the positive electrode 211 is preferably a graphite material, and the negative electrode 231 is preferably a non-graphitizable carbonaceous material.

  The electrode body 20 is accommodated coaxially in the negative electrode can 10 together with the non-aqueous electrolyte. The negative electrode can 10 is hermetically sealed at the sealing portion 30. The sealing portion 30 is configured using a positive terminal plate 31, a partition conductive plate 33, a fixed conductive plate 34, an electrically insulating resin sealing gasket 38, and the like.

  The positive electrode terminal plate 31 is a dish-shaped or hat-shaped metal part, and a sharp protrusion 32 is integrally formed on the inside thereof. The partition wall conductive plate 33 is a disk-shaped metal part, and is interposed between the positive electrode terminal plate 31 and the fixed conductive plate 34 to electrically connect the both 31 and 34, and airtightly isolates the both 31 and 34.

  The fixed conductive plate 34 is a dish-shaped metal part, and is electrically connected to the positive electrode current collector 212 of the electrode body 20 via the conductive lead 35, and its peripheral portion is formed between the positive electrode terminal plate 31 and the fixed conductive plate 34. It is folded inward with its peripheral edge wrapped. Thereby, the positive electrode terminal plate 31, the partition conductive plate 33, and the fixed conductive plate 34 are assembled and integrated in a conductive state.

  The sealing gasket 38 is interposed between the peripheral edge portion of the fixed conductive plate 34 and the opening portion of the negative electrode can 10 and is sandwiched between the bead portion 12 and the caulking portion 11 formed in the negative electrode can 10 in a compressed state. As a result, the negative electrode can 10 is hermetically sealed.

  A safety valve is formed by the positive terminal plate 31 and the partition conductive plate 33 in the sealing portion 30 described above. That is, the partition wall conductive plate 33 receives the pressure (internal pressure) in the negative electrode can 10, but when the internal pressure abnormally rises due to gas generation in the negative electrode can 10, the partition wall conductive plate 33 moves to the positive terminal plate 31. Pressed and deformed to the side. When this deformation exceeds a certain level, the central portion of the partition conductive plate 33 abuts against the sharp protrusion 32 and ruptures, thereby releasing the internal pressure and preventing the negative electrode can 10 from rupturing.

  On the inner bottom surface of the negative electrode can 10, a lithium metal 41 for preliminarily storing lithium ions in the negative electrode 231 is disposed together with an electrically insulating spacer member 50.

  As shown in the plan view of FIG. 2, the spacer member 50 is a member for maintaining a predetermined gap in the thickness direction, and the openings 51 extending in the thickness direction are dispersedly formed. As the shape of the spacer member 50, various modes are possible, for example, as shown in (a), (b) and (c) of FIG.

In FIG. 2, the spacer member 50 shown in FIG. 2A has an annular boss portion 53 that forms a through hole 52 in the center, and branch plate portions 54 having a predetermined thickness project radially from the boss portion 53. . A fan-shaped opening 51 is formed between the branch plate portions 54.
The spacer member 50 shown in (b) has a shape in which the tip portions of the branch plate portions 54 of (a) are connected by an annular portion 55, and is a fan-shaped portion surrounded by the plate branch portion 54 and the annular portion 55. Is an opening 51.
The spacer member 50 shown in (c) has an annular boss portion 53 that forms a through hole 52 in the center, and a disk portion 57 in which a large number of small through holes 56 are distributed, and each through hole 56 has an opening. 51 is formed.

  In the embodiment shown in FIG. 1, the pre-occlusion lithium metal 41 is disposed between the opening 51 of the spacer member 50 and the spacer member 50 and the inner bottom surface of the negative electrode can 10. The negative electrode can 10 is electrically connected to the negative electrode current collector 232 by a conductive lead 42.

  The conductive lead 42 is made of a strip-like or ribbon-like thin metal plate, and is resistance-welded to the central portion of the inner bottom surface of the negative electrode can 10 in order to ensure electrical connection with the negative electrode can 10 with low resistance. .

  The lithium metal 41 is placed in a short circuit state with the negative electrode 231 by being disposed together with the spacer member 50 on the inner bottom surface of the negative electrode can 10 to which the conductive lead 42 is welded.

  A center hole 25 extending in the axial direction is formed in the electrode body 20 accommodated coaxially in the negative electrode can 10. The through hole 52 of the spacer member 50 is provided so as to correspond to the center hole 25. The lithium metal 41 is disposed in a portion excluding the inside of the through hole 52 of the spacer member 50. The conductive lead 42 is welded to the bottom surface of the negative electrode can 10 inside the through hole 52.

  With such a configuration, the conductive lead 42 is welded by placing the lithium metal 41 together with the spacer member 50 on the inner bottom surface of the negative electrode can 10 and further housing the electrode body 20 in the negative electrode can 10. By inserting a rod-shaped welding electrode into the center hole 25, it can be performed smoothly. Thereafter, the nonaqueous electrolyte is injected and the negative electrode can 10 is sealed.

  The lithium metal 41 installed in a short circuit state with the negative electrode 231 is electrolytically eluted into the nonaqueous electrolytic solution to become lithium ions. The lithium ions move to the negative electrode 231 and are occluded.

  The lithium metal 41 that is a supply source of lithium ions is disposed on the inner bottom surface of the negative electrode can 10 and faces the winding end surface of the electrode body 20. For this reason, the lithium ions eluted from the lithium metal 41 move from the winding end surface to each part of the negative electrode 231 via the separator 22 and are occluded. That is, lithium ions move along the width direction with a short distance, not along the winding direction of the electrode body 20 with a long distance, and are occluded. Thereby, occlusion of lithium ions to the negative electrode 231 can be performed uniformly and smoothly.

  In this embodiment, the lithium metal 41 is disposed between the opening 51 of the separator member 50 and the spacer member 50 and the inner bottom surface of the negative electrode can 10. That is, a part of the lithium metal 41 is in a state hidden behind the spacer member 50 with respect to the electrode body 20. However, the lithium ions eluted from the lithium metal 41 in the portion can also move smoothly to the electrode body 20 through the opening 51 of the spacer member 50.

  A space remains in the trace where the lithium metal 41 is eluted in the non-aqueous electrolyte, but the spacer member 50 is interposed in the space, so that a constant space is provided between the winding end surface of the electrode body 20 and the inner bottom surface of the negative electrode can 10. Insulating gaps are ensured. Even if the end of the electrode body 20 is crushed by an impact such as dropping, the positive electrode current collector 212 is prevented from contacting the negative electrode can 10. Thereby, it is possible to prevent malfunction and gas generation due to an internal short circuit.

  As described above, in the above-described lithium ion storage element, it is possible to improve productivity by shortening a process period and a process line in which lithium metal is easily reacted and deteriorated. In addition, the pre-occlusion of lithium ions into the negative electrode 231 can be performed smoothly and uniformly. Furthermore, it is possible to improve the reliability by eliminating the cause of internal short circuit.

  FIG. 3 is a cross-sectional view showing another embodiment of the lithium ion storage element according to the present invention. The lithium ion storage element shown in the figure will be described by paying attention to differences from the above-described embodiment. The lithium metal 41 for pre-occlusion includes the opening 51 of the spacer member 50 and the spacer member 50 and the electrode body 20. It is arranged between.

  In this configuration, the spacer member 50 is not interposed between the lithium metal 10 and the electrode body 20, and all the upper surfaces of the lithium metal 10 face the end surfaces of the electrode body 20. Can be done.

<< Example >>
(1) Battery production Production of positive electrode: Graphite powder (SFG44 made by TIMCAL) as positive electrode material and carboxymethyl cellulose as binder are mixed at a weight ratio of 96: 4, and ion-exchanged water is added to form a paste mixture Was prepared. This mixture was applied to both surfaces of a 20 μm thick aluminum foil serving as a current collector. This was dried and rolled, and then cut to a width of 54 mm to produce a strip-shaped sheet electrode.

  A part of the mixture formed on the sheet electrode is scraped perpendicularly to the longitudinal direction of the sheet to expose a part of the aluminum foil, and an aluminum conductive lead plate is attached to the exposed part by ultrasonic welding. It was.

  Production of negative electrode: A non-graphitizable carbon material (PIC manufactured by Kureha Chemical), which is a negative electrode material, and a polyvinylidene fluoride resin, which is a binder, are mixed at a weight ratio of 80:20, and N-methyl-2-pyrrolidone is used as a solvent. In addition, a paste-like mixture was prepared. This mixture was applied to both sides of a 14 μm thick copper foil serving as a current collector. This was dried and rolled, and then cut to a width of 56 mm to produce a strip-shaped sheet electrode.

  A portion of the copper foil was exposed by scraping a part of the mixture formed on the sheet electrode perpendicularly to the longitudinal direction of the sheet, and a nickel conductive lead plate was attached to the exposed portion by resistance welding. .

  Production of electrode body: The produced negative electrode sheet and positive electrode sheet electrode were spirally wound with a polyethylene separator interposed therebetween to produce a cylindrical electrode body.

  Arrangement of lithium metal: Next, 0.04 g of a lithium metal foil punched out in a donut shape was arranged together with a polypropylene spacer member on the inner bottom of a cylindrical negative electrode can with a bottom.

  Thereafter, the electrode body is inserted into the negative electrode can. At the time of this insertion, the conductive lead plate connected to the negative electrode current collector is inserted between the lithium metal foil and the bottom surface of the negative electrode can. Then, a rod-shaped welding electrode was inserted from the center hole of the electrode body, and the lead plate was resistance welded to the central portion of the bottom surface of the negative electrode can.

(Example)
The above-described lithium ion storage element was produced in the following four examples (1 to 4) according to the positional relationship between the lithium metal foil and the spacer member and the shape of the spacer member.
Example 1 Lithium metal foil and a spacer member are arranged as shown in FIG. 1, and the spacer member having the shape shown in FIG.
Example 2: A lithium metal foil and a spacer member are arranged as shown in FIG. 1, and the spacer member having the shape shown in FIG. 2 (b) is used.
Example 3 Lithium metal foil and a spacer member are arranged as shown in FIG. 3, and the spacer member has the shape shown in FIG.
Example 4 Lithium metal foil and a spacer member are arranged as shown in FIG. 3, and the spacer member has the shape shown in FIG.

(Comparative example)
Moreover, the lithium ion electrical storage element mentioned above was produced in the following two types of comparative examples 1 and 2.
Comparative Example 1: A spacer member is disposed on a lithium metal foil, and the spacer member does not have an opening.
Comparative Example 2: A storage element was produced without arranging a lithium metal foil.

  (2) Evaluation.

  First, for Examples 1 to 4 and Comparative Example 1, the elution state of lithium metal after being left for 7 days was examined. In Examples 1 to 4, no undissolved lithium metal was observed. In Example 1, lithium metal remained undissolved.

  Next, about Examples 1-4 and Comparative Examples 1 and 2, after performing capacity | capacitance confirmation at room temperature, the floating charge test was done in a 60 degreeC thermostat. The test was allowed to stand for 5 hours after being placed in a thermostatic bath, and then started floating charging at a predetermined voltage. After performing floating charging for 500 hours, the battery was taken out from the thermostat, and the discharge capacity was measured at room temperature and the appearance was inspected. The results are shown in Table 1.

  As shown in the results of Table 1, the storage elements of Examples 1 to 4 and Comparative Example 1 manufactured by arranging the lithium metal for pre-occlusion did not have a large deterioration in discharge capacity even after floating charge. However, when compared in detail, a significant difference was observed between Examples 1 to 4 and Comparative Example 1. This is considered to be related to the preocclusion amount of lithium ions.

  As for the appearance, no deformation was observed in Examples 1 to 4 and Comparative Example 1. However, in Comparative Example 1, there was undissolved lithium metal. The undissolved lithium metal reacts violently and causes gas generation when moisture invades for some reason, which causes a reduction in the safety and reliability of the device.

  In Comparative Example 2, deformation was recognized in the appearance of the element. This means that gas generation has occurred inside. Further, in Comparative Example 2, the initial discharge capacity itself is low, and the discharge capacity after floating charge is much lower. However, these are considered to be related to the fact that no pre-occlusion of lithium ions was performed. It is done.

  As described above, the present invention has been described based on the typical embodiments. However, the present invention can have various modes other than those described above. For example, the present invention can be applied to power storage elements having various cylindrical shapes such as a square shape other than the cylindrical shape.

  In a lithium ion storage element having a configuration in which a cylindrical electrode body wound in a spiral shape is housed in a bottomed cylindrical metal negative electrode can together with a non-aqueous electrolyte, the productivity is improved and the reliability of the product is improved. Can be increased.

It is sectional drawing which shows one Embodiment of the lithium ion electrical storage element by this invention. It is a top view of the structural example of the spacer member used by this invention. It is sectional drawing which shows another embodiment of the lithium ion electrical storage element by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Negative electrode can 11 Caulking part 12 Bead part 20 Electrode body 21 Positive electrode part 211 Positive electrode 212 Positive electrode current collector 22 Separator 23 Negative electrode part 231 Negative electrode 232 Negative electrode current collector 25 Center hole 30 Sealing part 31 Positive electrode terminal board 32 Sharp protrusion part 33 Bulkhead conductive plate 34 Fixed conductive plate 35 Conductive lead (positive electrode) 38 Sealing gasket 41 Lithium metal 42 Conductive lead (negative electrode)
50 Spacer member 51 Opening portion 52 Through hole 53 Annular boss portion 54 Branch plate portion 55 Annular portion 56 Small through hole 57 Disk portion

Claims (4)

  A sheet-like positive electrode part composed of a positive electrode capable of occluding / releasing and adsorbing / desorbing anions and a current collector, and a sheet-shaped negative electrode part composed of a negative electrode capable of occluding and releasing lithium ions and a current collector A cylindrical electrode body wound in a spiral shape with a separator interposed therebetween, a non-aqueous electrolyte solution in which lithium salt is dissolved, and the electrode body together with the non-aqueous electrolyte solution are accommodated coaxially A lithium ion storage element including a bottomed cylindrical metal negative electrode can and a sealing portion that hermetically seals the opening of the negative electrode can, and a lithium metal for preliminarily storing lithium ions in the negative electrode; And an electrically insulating spacer member having an opening extending in the thickness direction, wherein the lithium metal is disposed on the inner bottom of the negative electrode can together with the spacer member, and the lithium metal is short-circuited with the negative electrode. Lithium-ion energy storage element.   2. The lithium ion storage element according to claim 1, wherein the lithium metal is disposed between the opening of the spacer member and between the spacer member and the bottom surface of the negative electrode can.   2. The lithium ion storage element according to claim 1, wherein the lithium metal is disposed between the opening of the spacer member and between the spacer member and the electrode body. 4. The spacer member and the lithium metal according to claim 1, wherein the spacer member and the lithium metal form a through hole at a position corresponding to the center hole of the electrode body, and the negative electrode and the lithium metal are formed inside the through hole. A lithium ion storage element, wherein a conductive lead to be electrically connected is welded to the bottom surface of the negative electrode can.

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