JP2017208188A - Battery outer package, nonaqueous electrolyte secondary battery, and battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a nonaqueous electrolyte secondary battery superior in cycle characteristics; a battery pack; and a battery outer package used therefor.SOLUTION: A pouch or box-like outer package 10 comprises: a battery part 40; at least first and second communicating parts 61, 62; and at least first and second pouched parts 51, 52. The battery part is communicated with the first pouched part through the first communicating part. The battery part is communicated with the second pouched part through the second communicating part. The battery part and the first pouched part are isolated from each other by a gas permeable film 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a battery exterior, a nonaqueous electrolyte secondary battery, and an assembled battery.

Non-aqueous electrolyte secondary batteries used in applications such as portable devices, hybrid vehicles, electric vehicles, and household power storage systems are required to have characteristics such as high safety, cycle stability, and high capacity. If gas accumulates inside and the battery swells, the distance between the electrodes may increase and the characteristics may be impaired.

  Patent document 1 is disclosing the nonaqueous electrolyte secondary battery which suppresses accumulation | storage of gas by including a carbon dioxide absorber. Moreover, patent document 2 is disclosing the electrochemical device which suppresses accumulation | storage of gas by including the hydrogen absorbent and oxygen absorbent which were wrapped with the gas permeable film.

JP 2007-242454 A JP 2014-127531 A

  However, in the techniques of Patent Documents 1 and 2, it is difficult to efficiently reduce the gas in the battery, and there is room for improvement in the cycle characteristics of the battery.

  An object of the present invention is to provide a non-aqueous electrolyte secondary battery and an assembled battery having excellent cycle characteristics, and a battery casing used therefor.

  The battery exterior according to the present invention has a bag-like or box-like shape, and has a space inside thereof, and the space has a battery part, at least first and second communication parts, and at least first and A second bag portion, the battery portion and the first bag portion are communicated via the first communication portion, and the battery portion and the second bag portion are communicated via the second communication portion. The battery part and the first bag part are separated by a gas permeable membrane.

  The battery exterior according to the present invention has a bag-like or box-like shape, and has a space inside thereof, and the space has a battery part, at least first and second communication parts, and at least first and A second bag portion, the battery portion and the first bag portion are communicated via the first communication portion, and the battery portion and the second bag portion are communicated via the second communication portion. The first bag portion contains the first absorbent and the second bag portion contains the second absorbent.

  According to the battery exterior according to the present invention, a nonaqueous electrolyte secondary battery and an assembled battery having excellent cycle characteristics can be obtained.

It is a top view of the battery exterior. It is a top view of the battery exterior.

  An embodiment of the nonaqueous electrolyte secondary battery according to the present invention will be described. The nonaqueous electrolyte secondary battery includes a laminate composed of a positive electrode, a negative electrode, and a separator, a nonaqueous electrolyte, a terminal, and a battery exterior.

<Positive electrode and negative electrode>
In the positive electrode and the negative electrode, an active material layer containing an active material capable of inserting and removing the electrolyte is formed on the current collector, and charging and discharging of the battery are performed by the insertion and removal.

  As the positive electrode active material, a metal oxide or a lithium transition metal composite oxide is preferably used. Among these, a plurality of positive electrode active materials may be used in combination.

  The thickness of the positive electrode active material layer is suitably used as long as it is 10 μm or more and 200 μm or less.

The density of the positive electrode active material layer is preferably 1.0 g / cm ³ or more and 4.0 g / cm ³ or less, and the balance between the contact of the positive electrode active material and the conductive additive and the penetration of the nonaqueous electrolyte is good. From a certain point, 1.5 g / cm ³ or more and 3.5 g / cm ³ or less are more preferable, and 2.0 g / cm ³ or more and 3.0 g / cm ³ or less are more preferable.

  The negative electrode active material is not particularly limited as long as it can insert and desorb metal ions, and may be appropriately selected in consideration of the combination with the positive electrode active material.

  As the negative electrode active material, a carbon-based active material, a metal oxide, a lithium metal oxide, or the like is preferably used. Among these, a plurality of negative electrode active materials may be used in combination.

  The thickness of the negative electrode active material layer is preferably 10 μm or more and 200 μm or less.

The density of the negative electrode active material layer is preferably 1.0 g / cm ³ or more and 3.0 g / cm ³ or less, and the balance between the contact of the negative electrode active material and the conductive additive and the penetration of the nonaqueous electrolyte is good. From a certain point, 1.3 g / cm ³ or more and 2.7 g / cm ³ or less are more preferable, and 1.5 g / cm ³ or more and 2.5 g / cm ³ or less are more preferable.

  The current collector is a member that collects current from each active material.

  The positive electrode and the negative electrode may be formed with the same active material layer on one side or both sides of the current collector, a form in which the positive electrode active material layer is formed on one side of the current collector and the negative electrode active material layer is formed on one side, that is, It may be a bipolar electrode.

  The thickness of the current collector is not particularly limited, but is preferably 10 μm or more and 100 μm or less.

  The positive electrode current collector is preferably aluminum or an alloy thereof, and is stable in the positive electrode reaction atmosphere. Therefore, high-purity aluminum typified by JIS standards 1030, 1050, 1085, 1N90, or 1N99 is used. Preferably there is.

As the current collector of the negative electrode, copper, SUS, nickel, titanium, aluminum, or an alloy thereof is preferable. These negative electrode current collectors may be coated with a metal that does not react at the negative electrode potential. The positive electrode and the negative electrode may further contain a conductive additive. As the conductive auxiliary material, any metal material or carbon material is preferably used.

  Copper or nickel is preferably used as the metal material of the conductive additive. Examples of the carbon material include natural graphite, artificial graphite, vapor-grown carbon fiber, carbon nanotube, acetylene black, ketjen black, and furnace black. These conductive aids may be used alone or in combination of two or more.

  The amount of the conductive additive contained in the positive electrode is preferably 1 part by weight or more and 30 parts by weight with respect to 100 parts by weight of the positive electrode active material from the viewpoint of a good balance between conductivity and adhesion to the current collector. The amount is more preferably 2 parts by weight or more and 15 parts by weight or less.

  The amount of the conductive additive contained in the negative electrode is preferably 1 part by weight or more and 30 parts by weight with respect to 100 parts by weight of the negative electrode active material from the viewpoint of a good balance between conductivity and adhesion to the current collector. The amount is more preferably 2 parts by weight or more and 15 parts by weight or less.

  The positive electrode and the negative electrode may further contain a binder. The binder is a material that enhances the binding properties of the active material, the conductive additive, and the current collector.

  The binder is not particularly limited as long as it is at least one selected from the group consisting of polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), styrene-butadiene rubber (SBR), polyimide, and derivatives thereof. Preferably used.

  The non-aqueous solvent for the binder is not particularly limited. Specific examples include N-methyl-2-pyrrolidone (NMP), dimethylformamide, dimethylacetamide, methyl ethyl ketone, methyl acetate, ethyl acetate, or tetrahydrofuran.

  Moreover, you may add a dispersing agent or a thickener to these binders.

  The amount of the binder is preferably 1 part by weight or more and 30 parts by weight or less, more preferably 2 parts by weight or more and 15 parts by weight or less, with respect to 100 parts by weight of the positive electrode or negative electrode active material. With such a binder amount, the adhesion between the active material and the conductive additive is maintained, and sufficient adhesion with the current collector can be obtained.

<Method for producing electrode>
As an electrode manufacturing method, a method of preparing an electrode including an active material layer by preparing a slurry of an active material, then supporting the slurry on a current collector, and removing the solvent from the slurry is suitably used. .

  A conventionally well-known technique should just be used for preparation of a slurry. Moreover, a conventionally well-known technique may be used also about the solvent of a slurry, carrying | support, and solvent removal.

<Separator>
The separator is installed at least between the positive electrode and the negative electrode, and has a function as a medium that mediates the conduction of lithium ions between them.

  As the separator, nylon, cellulose, polysulfone, polyethylene, polypropylene, polybutene, polyacrylonitrile, polyimide, polyamide, polyethylene terephthalate, and a combination of two or more of them are preferably used.

  The separator may be any shape as long as it is installed between the positive electrode and the negative electrode and can contain an insulating and non-aqueous electrolyte, and a woven fabric, a nonwoven fabric, a microporous membrane, or the like is preferably used.

  The separator may contain a plasticizer, an antioxidant, or a flame retardant, and may be coated with a metal oxide or the like.

  The thickness of the separator is preferably 10 μm or more and 100 μm or less, and more preferably 15 μm or more and 50 μm or less.

  The separator has a porosity of preferably 30% or more and 90% or less, and more preferably 35% or more and 85% or less from the viewpoint of a good balance between lithium ion diffusibility and short circuit prevention, and the balance is particularly excellent. Therefore, 40% or more and 80% or less is more preferable.

<Laminated body>
As a laminated body, each of a long positive electrode, a separator and a negative electrode is sequentially stacked and wound, or a single wafer positive electrode, a separator and a negative electrode are sequentially stacked, and a long separator is And the like, in which the positive electrode and the negative electrode are inserted one by one.

<Non-aqueous electrolyte>
The non-aqueous electrolyte has a function of mediating ion transmission between the positive electrode and the negative electrode.

  As the non-aqueous electrolyte, a non-aqueous electrolyte obtained by dissolving a solute in a non-aqueous solvent and a gel electrolyte obtained by impregnating a polymer with an electrolyte obtained by dissolving a solute in a non-aqueous solvent are preferably used.

  The non-aqueous solvent preferably includes a cyclic aprotic solvent and / or a chain aprotic solvent.

  As the cyclic aprotic solvent, cyclic carbonates, cyclic esters, cyclic sulfones and cyclic ethers are preferably used.

  As the chain aprotic solvent, a solvent generally used as a solvent for a nonaqueous electrolytic solution such as a chain carbonate, a chain carboxylic acid ester, a chain ether, or acetonitrile may be used.

  Specific examples of the chain aprotic solvent include dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, dipropyl carbonate, or methyl propyl carbonate. Specific examples of the cyclic aprotic solvent include ethylene carbonate, propylene carbonate, butylene carbonate, γ-butyl lactone, 1,2-dimethoxyethane, sulfolane, dioxolane, and methyl propionate.

  These solvents may be used alone or in combination of two or more. It is preferable to use a solvent in which two or more kinds are mixed from the viewpoint that the solubility of the solute described later and the metal ion conductivity are good.

  When two or more types are mixed, since the stability at high temperature is high and the lithium conductivity at low temperature is high, mixing of a chain carbonate and a cyclic carbonate is preferable.

  Specifically, one or more of chain carbonates such as dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, dipropyl carbonate, or methyl propyl carbonate, and ethylene carbonate, propylene carbonate, butylene carbonate, or γ-butyl lactone, etc. Mixing with one or more of cyclic carbonates is preferable, and mixing with one or more of dimethyl carbonate, methyl ethyl carbonate, or diethyl carbonate and one or more of ethylene carbonate, propylene carbonate, or butylene carbonate is mentioned. .

  As the mixed solvent of the chain carbonate and the cyclic carbonate, the ratio of the chain carbonate is preferably 5% by volume to 95% by volume. If it is within this range, the viscosity of the non-aqueous solvent falls within an appropriate range, so that favorable rate characteristics of the battery can be obtained.

  Since the mixed solvent of the chain carbonate and the cyclic carbonate has a good balance between viscosity and dissolved mass, the ratio of the chain carbonate is preferably 10% by volume to 90% by volume, more preferably the balance is particularly good. Therefore, 20% by volume to 80% by volume is more preferable.

The solute suitably used as long as it is a compound containing lithium and _{halogen, LiClO 4, LiBF 4, LiPF} 6, LiAsF 6, LiCF 3 SO 3, LiBOB (Lithium Bis (Oxalato) Borate), or LiN (SO ₂ CF _{3) 2} is more preferable.

  The concentration of the solute is preferably 0.5 mol / L or more and 2.0 mol / L or less. If it is 0.5 mol / L or less, lithium ion conductivity is good. On the other hand, if it is 2.0 mol / L or less, the solubility of the solute is good.

  The amount of the nonaqueous electrolytic solution is not particularly limited, but is preferably 0.1 mL or more per 1 Ah of battery capacity. If it is this amount, the conduction of the metal ion accompanying an electrode reaction, specifically, lithium ion is ensured.

<Terminal>
The terminal is a member that electrically connects the non-aqueous electrolyte secondary battery and the external device, and is connected to at least one of the positive electrode and the negative electrode.

  As the terminal, a conductor is preferably used, and aluminum is more preferable from the viewpoint of a good balance between performance and cost.

<Battery exterior>
The battery exterior according to the present invention will be described with reference to FIGS. 1 and 2 as an embodiment for easy understanding. 1 and 2, a first communication portion 61 is formed adjacent to the battery portion 40 and the first bag portion 51, and the battery portion 40, the second bag portion 52, A second communication portion 62 is formed adjacent to the second communication portion 62. The first bag portion 51 and the second bag portion 52 are located at a position separated from the battery portion 40.

  The battery exterior 10 has a bag-like shape having a space inside thereof, and after enclosing a laminated body or the like inside, prevents intrusion of moisture into the space, and leaks nonaqueous electrolyte from the space. In order to provide a function to prevent, the space is cut off from the external atmosphere. As long as it has the function, the shape is not particularly limited, and may be a bag shape or a box shape, for example.

  It is preferable that the space of the battery exterior 10 is variable in volume since the volume of the entire battery can be reduced while storing more gas in the bag portion.

  The battery exterior 10 is formed with a battery part 40, bag parts 51 and 52, and communication parts 61 and 62 as spaces.

  As a material for the battery casing 10, a laminate film is preferably used. Specific examples of laminate films include a composite film in which a metal foil is provided with a heat-sealable thermoplastic resin layer, or a metal foil prepared by vapor deposition or sputtering on a heat-sealable thermoplastic resin layer. Composite film.

  As the metal foil of the composite film, aluminum is suitably used because it has a good moisture barrier property and a good balance between weight and cost.

  As the thermoplastic resin layer of the composite film, polyethylene or polypropylene is preferably used from the viewpoint that the heat seal temperature range and the non-aqueous electrolyte barrier property are good. In order to improve the adhesion between the metal foil and the thermoplastic resin, a laminate adhesive layer may be provided between them.

  In order to prevent oxidation of the metal foil, a laminate protective layer may be provided on the metal foil.

  As a method of creating a space in the battery exterior 10 using a laminate film, a method of bonding two films together and forming them into a bag shape may be used. A method of forming into a shape may be used.

  The battery unit 40 encloses a laminate composed of a positive electrode, a negative electrode and a separator, and a non-aqueous electrolyte.

  The bag parts 51 and 52 have a function as a gas pocket for storing gas generated from the battery.

  The battery exterior 10 has at least two bag portions. That is, the battery exterior has at least a first bag portion and a second bag portion.

  The first and second bag portions are independent of each other. That is, the first bag part 51 and the battery part 40 communicate with each other via the first communication part 61, and the second bag part 52 and the battery part 40 communicate with each other via the second communication part 62. To do.

  The communication parts 61 and 62 have a function of allowing gas generated from the battery to pass from the battery part to the bag part.

  The size of the cross section perpendicular to the communication direction in the communication portions 61 and 62 is not particularly limited, but is preferably 25% or less with respect to the cross section perpendicular to the communication direction in the battery portion, preferably 1% or more and 25% or less. More preferably, it is more preferably 1% or more and 10% or less.

<Gas permeable membrane>
In one embodiment of the invention, the first bag portion 51 and the battery portion 40 are separated by the gas permeable membrane 11.

  The gas permeable membrane has a function of transmitting only a specific gas.

  As the gas permeable membrane, palladium (Pd), platinum, nickel alloy, alumina, zirconia, silica, zeolite, PTFE, polyimide, polysulfone, or polydimethylsiloxane is preferably used.

  One type of gas permeable membrane may be used, or two or more types may be used in combination.

  The gas permeable membrane is preferably a hydrogen permeable membrane that selectively permeates hydrogen for the purpose of collecting hydrogen.

  A polyimide or Pd film is preferably used as the hydrogen permeable film.

  The gas permeable film of the present invention may be formed, for example, by bonding a gas permeable film to an aluminum laminate sheet and then heat-sealing the gas permeable film and the aluminum laminate sheet. In addition, it is formed by forming a permeable membrane on a porous substrate, and then blocking the space between the battery portion and the first bag portion by fixing the substrate to the exterior material with an adhesive. Also good.

<Absorbent>
In one embodiment of the invention, the first bag portion 51 includes the first absorbent 12 and the second bag portion 52 includes the second absorbent 22.

  The absorbents 21 and 22 have a function of adsorbing a specific gas.

  As the form of the absorbent, at least one selected from the group consisting of a solid, a liquid and an ionic liquid is preferably used.

  When the absorbent is solid, it is preferable to fix the absorbent in the bag portion using an absorbent binder. The absorbent binder may be the same as or different from the binder contained in the active material layer.

  Specific examples of the absorbent binder include PVdF or SBR.

  When the absorbent is a liquid or an ionic liquid, it is preferably used by impregnating a polymer film or an inorganic film.

  The amount of the absorbent is appropriately adjusted according to the amount of gas to be absorbed.

  As the absorbent, a hydrogen absorbent or a carbon dioxide absorbent is preferably used.

  As the hydrogen absorbent, hydrogen absorbing metal, zeolite, silica, carbon nanotube, silica gel, and alumina are preferably used, and as the hydrogen absorbing metal, Pd or Pd alloy is preferably used.

  As the carbon dioxide absorbent, zeolite, lithium zirconate, alumina, activated carbon, silica, aqueous ammonium solution, calcium hydroxide, or sodium hydroxide is preferably used, more preferably zeolite, and more preferably 13X type zeolite. .

  It is preferable that the gas permeable membrane 11 and the first absorbent 12 are used together from the viewpoint of efficiently reducing the gas by absorbing only the specific gas with the specific absorbent.

  In particular, it is preferable that the hydrogen absorbent is included in the first bag portion including the hydrogen permeable membrane from the viewpoint of efficiently reducing the gas by absorbing the specific gas with the specific absorbent, and further the second More preferably, the bag portion includes a carbon dioxide absorbent and a carbon dioxide permeable membrane.

  In the above description, the case of having the first and second bag portions has been described as an example. However, the present invention has at least the first and second bag portions, and the third or more bag portions are provided. You may have a bag part.

  Further, in the above description, the case where the first and second absorbents are included has been described as an example. However, the present invention includes at least the first and second absorbents, and includes a third or higher absorbent. You may have an absorber.

<Method for producing non-aqueous electrolyte secondary battery>
In the production of the nonaqueous electrolyte secondary battery, the laminate may be impregnated with the nonaqueous electrolyte and then accommodated in the battery exterior 10, or the laminate may be accommodated in the battery exterior 10 and then nonaqueous. An electrolytic solution may be injected.

  Specifically, first, the battery exterior 10 is formed by heat sealing while leaving the space necessary for the injection of the nonaqueous electrolyte in the battery part 40, and then the nonaqueous electrolyte is injected from the unsealed part of the battery part 40. And the method of heat-sealing the said location is mentioned.

  Heat sealing is preferably performed in a reduced-pressure atmosphere.

  The manufacturing method of the nonaqueous electrolyte secondary battery may include an aging process in which the nonaqueous electrolyte secondary battery is allowed to stand at a predetermined charge state, temperature, and time. The aging process decomposes impurities in the battery and generates gas.

  The aging step may include a step of standing at 40 to 70 ° C. for 10 to 200 hours (also referred to as heat aging).

  The aging step may include a step of charging / discharging 1 to 10 cycles at 60 ° C. (also referred to as initial charge / discharge).

  The aging step preferably includes at least one heating aging and initial charge / discharge.

<Battery assembly>
Two or more nonaqueous electrolyte secondary batteries may be combined to form an assembled battery.

  The assembled battery may be appropriately connected in series and / or in parallel according to a desired size, capacity, or voltage.

  The assembled battery is preferably provided with a control circuit for confirming the state of charge of each battery and improving safety.

  In order to efficiently capture the gas generated in the battery, in the assembled battery generated in the battery, the exterior of the nonaqueous electrolyte secondary battery is such that the first bag portion is on the ceiling (upper) side, It is preferable that the second bag portion be on the ground (lower) side. That is, it is preferable that the battery is a battery assembly in which the batteries are arranged vertically so that the first bag portion is on the top and the second bag portion is on the bottom.

  Further, in order to efficiently remove the gas generated inside, a hydrogen absorbent is sealed in the first bag portion of the nonaqueous electrolyte secondary battery in the assembled battery, and a carbon dioxide absorbent is placed in the second bag portion. It is preferable to place the battery exterior 10 in the battery so that the battery is sealed and the first bag portion is on the ceiling side and the second bag portion is on the ground side.

  With such a configuration, hydrogen and carbon dioxide, which are main components of the gas in the battery, are more efficiently reduced. That is, since hydrogen is lighter than carbon dioxide, it is collected in the bag portion on the ceiling side and then absorbed by the hydrogen absorbent. On the other hand, carbon dioxide is collected in the bag portion on the ground side and then absorbed by the carbon dioxide absorbent.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

Example 1
(Preparation example of positive electrode)
The positive electrode active material Li _1.1 Al _0.1 Mn _1.8 O ₄ (LAMO) is produced by the method described in the literature (Electrochemical and Solid-State Letters, 9 (12), A557 (2006)). did.

  That is, an aqueous dispersion of manganese dioxide, lithium carbonate, aluminum hydroxide, and boric acid was prepared, and a mixed powder was obtained by a spray drying method. At this time, the amounts of manganese dioxide, lithium carbonate and aluminum hydroxide were adjusted so that the molar ratio of lithium, aluminum and manganese was 1.1: 0.1: 1.8. Next, the mixed powder was heated at 900 ° C. for 12 hours in an air atmosphere, and then again heated at 650 ° C. for 24 hours. The powder was washed with water at 95 ° C. and then dried to obtain a positive electrode active material.

  Next, a positive electrode active material, acetylene black as a conductive additive, and PVdF as a binder were mixed so as to have a solid content concentration of 100 parts by weight, 5 parts by weight, and 5 parts by weight, respectively, to obtain a positive electrode slurry. At this time, the binder was adjusted to a 5 wt% N-methyl-2-pyrrolidone (NMP) solution.

Then, the positive electrode slurry was coated on both sides of an aluminum foil having a thickness of 20 μm, and then dried in an oven at 150 ° C. The positive electrode was obtained through the above steps. At this time, the area of the positive electrode was 50 cm ² .

(Production example of negative electrode)
The negative electrode active material Li ₄ Ti ₅ O ₁₂ was produced by a method described in the literature (Journal of Electrochemical Society, 142, 1431 (1995)).

  That is, first, titanium dioxide and lithium hydroxide are mixed so that the molar ratio of titanium and lithium is 5: 4, and then this mixture is heated at 800 ° C. for 12 hours in a nitrogen atmosphere to obtain a negative electrode active material. Obtained.

  Next, the negative electrode active material, acetylene black as a conductive additive, and PVdF as a binder were mixed so as to have a solid content concentration of 100 parts by weight, 5 parts by weight, and 5 parts by weight, respectively, to obtain a negative electrode slurry. At this time, the binder was adjusted to a 5 wt% N-methyl-2-pyrrolidone (NMP) solution.

Then, the negative electrode slurry was coated on both sides of an aluminum foil having a thickness of 20 μm, and then dried in an oven at 150 ° C. The negative electrode was obtained through the above steps. At this time, the area of the negative electrode was 50 cm ² .

(Nonaqueous electrolyte production example)
Next, LiPF ₆ was mixed in a mixed solvent of ethylene carbonate / dimethyl carbonate = 30/70 vol% at a concentration of 1 mol / L. Thereafter, ethylenediamine as an amine compound was mixed at a concentration of 0.1 wt%. A nonaqueous electrolyte was obtained through the above steps.

(Production example of non-aqueous electrolyte secondary battery)
Next, 13 positive electrodes and 14 negative electrodes were alternately laminated via a cellulose nonwoven fabric separator to obtain a laminate. Thereafter, terminals were attached to each of the positive electrode and the negative electrode of the laminate. Thereafter, the laminate was put in an aluminum laminate sheet bag formed into a bag shape by heat-sealing the periphery. Thereafter, the aluminum laminate sheet bag was heat-sealed to divide the space to form a battery part, first and second bag parts, and a communication part. At this time, using the Pd membrane as a gas permeable membrane separating the first bag portion and the battery portion with the first bag portion on the top (ceiling side), the second bag portion on the bottom (ground side), When the aluminum laminated bag was manufactured, a Pd film was installed on the first communicating portion by heat sealing.

  Then, the hydrogen absorption alloy which is a hydrogen absorbent was put into the 1st bag part as a 1st absorbent.

  Then, the zeolite 13X which is a carbon dioxide absorber was put into the 2nd bag part as a 2nd absorber.

  And 5 ml of non-aqueous electrolyte was put in the battery part, and it sealed, reducing a bag-shaped aluminum laminate sheet after that. A nonaqueous electrolyte secondary battery was obtained through the above steps.

(Example 2)
Example 1 was the same as Example 1 except that the first bag part was down (ground side) and the second bag part was up (ceiling side).

(Example 3)
The same as Example 1 except that no gas permeable membrane was formed.

Example 4
Example 1 was the same as Example 1 except that the first absorbent was zeolite 13X and the second absorbent was a hydrogen absorbing alloy.

(Example 5)
The same as Example 1 except that no hydrogen absorbing alloy was added.

(Example 6)
The same as Example 1 except that zeolite 13X was not added.

(Example 7)
The first bag portion was formed on the lower side (ground side), and the second bag portion was formed on the upper side (ceiling side). Further, no absorbent was put in the first bag portion, and the absorbent in the second bag portion was a hydrogen absorbing alloy. The rest was the same as in Example 1.

(Example 8)
The same as Example 1 except that the hydrogen absorbing alloy and zeolite 13X were not added.

(Comparative Example 1)
The same as Example 1 except that the second bag portion was not formed.

(Comparative Example 2)
Example 2 was the same as Example 1 except that the second bag part and the gas permeable membrane were not formed.

(Comparative Example 3)
Example 2 was the same as Example 1 except that the second bag portion was not formed and the first absorbent was zeolite 13X.

(Comparative Example 4)
The same as Example 1 except that the first bag portion was not formed.

(Comparative Example 5)
The first bag portion was not formed, and no second absorbent was added. Except for these, it was the same as Example 1.

(Comparative Example 6)
The second bag part was not formed and the first absorbent was not added. Except for these, it was the same as Example 1.

(Comparative Example 7)
The gas permeable membrane and the second bag portion were not formed, and the first absorbent was not added. Except for these, it was the same as Example 1.

(Comparative Example 8)
A gas permeable membrane was not formed, and the same procedure as in Example 1 was performed except that a hydrogen absorbing alloy and zeolite 13X were not added.

(Comparative Example 9)
Example 1 was the same as Example 1 except that the first bag part and the second bag part were not formed.

(Cycle test method)
The nonaqueous electrolyte secondary batteries produced in the examples and comparative examples were connected to a charge / discharge device (HJ1005SD8, manufactured by Hokuto Denko), and a cycle test was performed.

  In the cycle test, first, constant current charging is performed in a 60 ° C. environment at a current value equivalent to 0.5 C until the battery voltage reaches a final voltage of 2.7 V, and then switching to constant voltage charging is performed. The charging was stopped when the current value decreased to.

  Next, constant current discharge was performed at a current value corresponding to 1.0 C, and the discharge was stopped when the battery voltage reached 2.0V. The charging and discharging were repeated once, and charging and discharging were repeated 1000 cycles.

  The percentage of the discharge capacity at the 1000th cycle with respect to the discharge capacity at the 1st cycle was defined as the capacity retention rate.

(Measurement of amount of generated gas)
After the cycle test, the amount of gas accumulated in the battery was calculated from the area of the bag portion and the height of the bag portion swollen by the generated gas. In addition, since the inside of a battery cannot be made into a complete vacuum state at the time of aluminum laminate sheet sealing, suppose that the bag part before a cycle life test has a fixed volume.

  And the gas in a battery was analyzed by the atmospheric pressure ionization measuring method, and the ratio of the carbon dioxide gas and hydrogen gas in generated gas was computed.

(Review of Table 1)
In Examples 1 to 13, the capacity retention rate was as high as 85% or more, and non-aqueous electrolyte secondary batteries having excellent cycle characteristics were obtained.

DESCRIPTION OF SYMBOLS 10 Battery exterior 11 Gas permeable membrane 21 1st absorbent 22 2nd absorbent 40 Battery part 51 1st bag part 52 2nd bag part 61 1st communication part 62 2nd communication part

Claims (10)

A bag-like or box-like exterior having a space inside, wherein the space includes a battery part, at least first and second communication parts, and at least first and second bag parts, and the battery And the first bag portion are communicated via the first communication portion, the battery portion and the bag portion are communicated via the second communication portion, and the battery portion and the first bag are communicated. The battery exterior characterized by being separated from the part by a gas permeable membrane. The battery exterior according to claim 1, wherein the gas permeable membrane includes a hydrogen permeable membrane. The battery exterior according to claim 1, wherein the first bag portion includes a first absorbent. The battery exterior according to claim 3, wherein the first absorbent contains a hydrogen absorbent. A bag-like or box-like exterior having a space inside, wherein the space includes a battery part, at least first and second communication parts, and at least first and second bag parts, and the battery And the first bag portion are communicated via the first communication portion, the battery portion and the second bag portion are communicated via the second communication portion, and the first The battery outer part has a first absorbent, and the second bag part has a second absorbent. The battery exterior according to claim 5, wherein the first absorbent includes a hydrogen absorbent and the second absorbent includes a carbon dioxide absorbent. 7. The battery exterior according to claim 5, comprising the gas permeable membrane according to claim 1. A nonaqueous electrolyte secondary battery comprising the battery outer package according to claim 1, a laminate composed of a positive electrode, a negative electrode, and a separator, a nonaqueous electrolytic solution, and a terminal.   An assembled battery comprising at least one nonaqueous electrolyte secondary battery according to claim 8. The assembled battery according to claim 9, wherein the first bag portion is disposed on a ceiling side of the battery portion, and the second bag portion is disposed on a ground side of the battery portion.