TW201838239A - Assembled battery - Google Patents

Assembled battery Download PDF

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TW201838239A
TW201838239A TW107106886A TW107106886A TW201838239A TW 201838239 A TW201838239 A TW 201838239A TW 107106886 A TW107106886 A TW 107106886A TW 107106886 A TW107106886 A TW 107106886A TW 201838239 A TW201838239 A TW 201838239A
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battery
metal
batteries
battery pack
box type
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TW107106886A
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中村仁
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日商山葉發動機股份有限公司
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/218—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by the material
    • H01M50/22—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by the material of the casings or racks
    • H01M50/222—Inorganic material
    • H01M50/224—Metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
    • H01M10/0562—Solid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/103—Primary casings; Jackets or wrappings characterised by their shape or physical structure prismatic or rectangular
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/107—Primary casings; Jackets or wrappings characterised by their shape or physical structure having curved cross-section, e.g. round or elliptic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204—Racks, modules or packs for multiple batteries or multiple cells
    • H01M50/207—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape
    • H01M50/209—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape adapted for prismatic or rectangular cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204—Racks, modules or packs for multiple batteries or multiple cells
    • H01M50/207—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape
    • H01M50/213—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape adapted for cells having curved cross-section, e.g. round or elliptic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/271—Lids or covers for the racks or secondary casings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Battery Mounting, Suspending (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)
  • Sealing Battery Cases Or Jackets (AREA)
  • Secondary Cells (AREA)

Abstract

An assembled battery (16) has a plurality of lithium ion cells (161) that are electrically connected to each other. Each of the lithium ion cells (161) is a metal case-type cell that has a metal case for housing a positive electrode, a negative electrode, and an electrolyte. Each of the respective metal case-type cells (161) is connected in series to one of the metal case-type cells (161). The positive electrode has a positive electrode active material of an olivine structure. The negative electrode has a negative electrode active material which includes a plurality of carbon layers stacked on top of each other and in which the average interlayer distance among the carbon layers is equal to or more than the diameter of a lithium atom. The assembled battery (16) has a metal case-type cell fixing part (163) that fixes the metal case-type cells (161) to each other.

Description

電池組Battery

本發明係關於一種具有複數個鋰離子電池之電池組。The present invention relates to a battery pack having a plurality of lithium ion batteries.

於車輛或電子設備，搭載有二次電池。先前，使用鉛蓄電池作為二次電池。近年來，代替鉛蓄電池，而使用鋰離子電池作為二次電池。 例如，於專利文獻1中提出一種具有串聯連接之複數個鋰離子電池之鋰離子電池組。專利文獻1中所記載之鋰離子電池具有正極及負極，該正極具有包含磷酸鐵鋰之正極活性物質，該負極具有石墨系之負極活性物質。[先前技術文獻] [專利文獻] [專利文獻1]日本專利第5549684號公報A secondary battery is mounted on a vehicle or an electronic device. Previously, lead storage batteries were used as secondary batteries. In recent years, instead of a lead storage battery, a lithium ion battery has been used as a secondary battery. For example, Patent Document 1 proposes a lithium ion battery pack having a plurality of lithium ion batteries connected in series. The lithium ion battery described in Patent Document 1 has a positive electrode and a negative electrode, and the positive electrode has a positive electrode active material containing lithium iron phosphate, and the negative electrode has a graphite-based negative electrode active material. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent No. 5549684

[發明所欲解決之問題] 本案之發明者研究了將如專利文獻1中所記載之鋰離子電池組代替鉛蓄電池而搭載於機車等跨坐型車輛。其結果明確了，因跨坐型車輛之使用環境，會導致鋰離子電池劣化。 本發明係提供一種即便為搭載於跨坐型車輛之電池組之使用環境、亦可抑制鋰離子電池之劣化之電池組。 [解決問題之技術手段] 本案之發明者對搭載於跨坐型車輛之鉛蓄電池之使用環境與搭載於汽車(四輪車)之鉛蓄電池之使用環境進行了比較研究。 於以引擎作為驅動源之跨坐型車輛及以引擎作為驅動源之汽車中，鉛蓄電池係於引擎起動時，以大電流進行放電以便實現啟動馬達之驅動。於以馬達作為驅動源之跨坐型車輛及以馬達作為驅動源之汽車中，鉛蓄電池係於行駛時以大電流進行放電以便實現啟動馬達之驅動。以引擎作為驅動源之汽車具備用以收容引擎之引擎室。又，以馬達作為驅動源之汽車具備用以收容馬達之馬達室。搭載於汽車之鉛蓄電池係收容於引擎室或馬達室。因此，即便於冬季之夜間等低溫環境下，搭載於汽車之鉛蓄電池之溫度亦不易變得極端低溫。與此相對，跨坐型車輛不具備引擎室或馬達室。搭載於跨坐型車輛之鉛蓄電池係以露出至外部之狀態或僅由車體外殼覆蓋之狀態配置。因此，於冬季之夜間等低溫環境下，搭載於跨坐型車輛之鉛蓄電池之溫度大幅度地降低。因此，搭載於跨坐型車輛之鉛蓄電池有在較搭載於汽車之鉛蓄電池更低溫之狀態下進行大電流之放電之傾向。 又，跨坐型車輛與汽車相比，更要求車輛之輕量化及小型化。以引擎作為驅動源之跨坐型車輛之鉛蓄電池可使用與搭載於以引擎作為驅動源之汽車之鉛蓄電池相比重量及體積較小者。即，搭載於以引擎作為驅動源之跨坐型車輛之鉛蓄電池與搭載於以引擎作為驅動源之汽車之鉛蓄電池相比，容量較小。又，搭載於以馬達作為驅動源之跨坐型車輛之鉛蓄電池可使用與搭載於以馬達作為驅動源之汽車之鉛蓄電池相比重量及體積較小者。即，搭載於以馬達作為驅動源之跨坐型車輛之鉛蓄電池與搭載於以馬達作為驅動源之汽車之鉛蓄電池相比，容量較小。如此，搭載於跨坐型車輛之鉛蓄電池與搭載於汽車之鉛蓄電池相比容量較小，故而搭載於跨坐型車輛之鉛蓄電池有較搭載於汽車之鉛蓄電池被充電頻度更高之傾向。 因此，搭載於跨坐型車輛之鉛蓄電池有在較搭載於汽車之鉛蓄電池更低溫之狀態下較搭載於汽車之鉛蓄電池更頻繁地被充電之傾向。 如此，本案之發明者發現，搭載於跨坐型車輛之鉛蓄電池有在較搭載於汽車之鉛蓄電池更低溫之狀態下進行大電流之放電之傾向，且有在較搭載於汽車之鉛蓄電池更低溫之狀態下較搭載於汽車之鉛蓄電池更頻繁地被充電之傾向。本案之發明者研究了於跨坐型車輛中代替鉛蓄電池而搭載如專利文獻1中所記載之鋰離子電池組。但，注意到由於搭載於跨坐型車輛之鉛蓄電池之使用環境為如上所述之環境，故而當將如專利文獻1中所記載之鋰離子電池組搭載於跨坐型車輛時，鋰離子電池容易劣化。 本案之發明者針對使專利文獻1中所記載之具有包含磷酸鐵鋰之正極活性物質、及石墨系之負極活性物質之鋰離子電池於低溫狀態下進行充電及放電進行了研究。其結果，可知以下內容。 可知鋰離子電池即便於低溫環境下亦可實現跨坐型車輛所需之大電流之放電。又，可知於花費時間將鋰離子電池緩慢地進行充電之情形時，即便於低溫環境下反覆進行放電，鋰離子電池亦不易劣化。 但，可知於在低溫環境下反覆進行鋰離子電池之充電之情形時，鋰離子電池容易劣化。 具有石墨系之負極活性物質之負極具有碳石墨(石墨)層積層而成之結晶結構。 於鋰離子電池充電時，鋰離子係自正極向負極移動，並進入至負極中經積層之石墨層之間。另一方面，於鋰離子電池放電時，鋰離子係自負極中之石墨層之間離開，並向正極移動。 於負極中，石墨層之間之距離稍小於鋰原子之直徑。因此，當於鋰離子電池充電時鋰離子進入至負極中之石墨層之間時，石墨層之間擴寬。另一方面，當於鋰離子電池放電時鋰離子自石墨層之間離開時，石墨層之間縮窄。於反覆進行鋰離子電池之充電及放電之情形時，鋰離子反覆進出石墨層之間，因此，石墨層之間隙反覆擴大與縮小。其結果，石墨層之積層狀態變化。因此，可知負極之結晶結構大幅度地變化。可知該情況為導致負極劣化之一主要原因。 本案之發明者研究了，於鋰離子電池之負極使用具有經積層之複數個碳層之負極活性物質，而非使用具有經積層之複數個石墨層之負極活性物質。此處之碳為非石墨(non-graphite)。更具體而言，對作為負極活性物質使用複數個碳層之平均層間距離為鋰離子之直徑以上之負極活性物質進行了研究。其結果，可知以下內容。 複數個碳層之平均層間距離為鋰離子之直徑以上，故而即便於鋰離子電池充電時鋰離子進入至負極之相鄰之碳層之間，相鄰之碳層之間亦幾乎未擴寬。又，即便於鋰離子電池放電時鋰離子自相鄰之碳層之間離開，相鄰之碳層之間之距離亦不太變化。即，即便於鋰離子電池之充電時及放電時鋰離子進出碳層之間，複數個碳層之平均層間距離亦幾乎未變化。因此，複數個碳層之積層狀態幾乎未變化。藉此，可知負極之結晶結構不太變化。因此，可知能夠抑制負極之劣化。因此，可知能夠抑制具有該負極之鋰離子電池之劣化。又，可知由於負極具有上述構成，故而即便鋰離子電池之充電及放電之頻度變高，亦可抑制鋰離子電池之劣化。進而，可知由於負極具有上述構成，故而即便具有該負極之鋰離子電池於低溫之狀態下進行充電或放電，亦可抑制劣化。因此，可知即便將該鋰離子電池搭載於跨坐型車輛，且於低溫之狀態下鋰離子電池之充電及放電之頻度變高，亦可抑制鋰離子電池之劣化。 根據以上見解，本案之發明者完成了本發明。以下，對本發明進行說明。 (1)本發明之電池組係具有相互電性連接之複數個鋰離子電池者，且上述複數個鋰離子電池之各者係金屬盒型電池，具有：1個正極；1個負極；電解液或固體電解質；及金屬製之盒，其收容上述1個正極、上述1個負極、及上述電解液或固體電解質；且上述複數個金屬盒型電池之各者係與上述複數個金屬盒型電池中之任一者串聯連接，上述正極具有橄欖石結構之正極活性物質，上述負極具有負極活性物質，該負極活性物質包含經積層之複數個碳層且上述複數個碳層之平均層間距離為鋰原子之直徑以上，上述電池組具有金屬盒型電池固定部，該金屬盒型電池固定部係將上述複數個金屬盒型電池相互固定。 根據該構成，複數個金屬盒型電池之各者係與複數個金屬盒型電池中之任一者串聯連接。相互串聯連接之金屬盒型電池之數量越多，則電池組之輸出電壓越高。藉由使相互串聯連接之金屬盒型電池之數量變多，可於需要較高之輸出電壓之使用環境中使用電池組。 金屬盒型電池係鋰離子電池。鋰離子電池與鉛蓄電池相比，重量能量密度及體積能量密度較小。因此，於代替鉛蓄電池而將具有複數個鋰離子電池之電池組搭載於跨坐型車輛之情形時，可維持電瓶(battery)之容量，且可使跨坐型車輛輕量化及小型化。或者，可不使跨坐型車輛大型化及重量化而增大電瓶之容量。藉由使電池組之容量額外增大，電池組所具有之複數個金屬盒型電池之各者之負擔減輕，故而可抑制金屬盒型電池之劣化。 複數個金屬盒型電池(鋰離子電池)之各者具有1個正極、1個負極、及電解液或固體電解質。金屬盒型電池之負極包含負極活性物質，該負極活性物質包含碳層而非石墨層，且複數個碳層之平均層間距離為鋰原子之直徑以上。 由於複數個碳層之平均層間距離為鋰離子之直徑以上，故而即便於金屬盒型電池充電時鋰離子進入至負極之相鄰之碳層之間，相鄰之碳層之間亦幾乎未擴寬。又，即便於金屬盒型電池放電時鋰離子自相鄰之碳層之間離開，相鄰之碳層之間之距離亦不太變化。即，即便於金屬盒型電池之充電時及放電時鋰離子進出碳層之間，複數個碳層之平均層間距離亦幾乎未變化。因此，碳層之積層狀態幾乎未變化。藉此，負極之結晶結構不太變化。因此，可抑制負極之劣化。因此，具有該負極之金屬盒型電池可抑制劣化。因此，可抑制具有該負極之金屬盒型電池之劣化。又，由於負極具有上述構成，故而即便金屬盒型電池之充電及放電之頻度變高，亦可抑制金屬盒型電池之劣化。進而，由於負極具有上述構成，故而具有該負極之金屬盒型電池係即便於低溫之狀態下亦可抑制劣化。因此，即便將該金屬盒型電池搭載於跨坐型車輛，且於低溫之狀態下金屬盒型電池之充電及放電之頻度變高，亦可抑制金屬盒型電池(鋰離子電池)之劣化。 又，由於金屬盒型電池之正極包含具有橄欖石結構之正極活性物質，故而即便反覆進行充電與放電，金屬盒型電池(鋰離子電池)亦不易劣化。因此，即便於低溫環境下反覆進行金屬盒型電池之充電與放電，金屬盒型電池(鋰離子電池)亦不易劣化。因此，即便將具有複數個金屬盒型電池之電池組搭載於跨坐型車輛，並相對較為頻繁地反覆進行電池組之充電與放電，亦可抑制金屬盒型電池(鋰離子電池)之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制金屬盒型電池(鋰離子電池)之劣化。 進而，正極活性物質所具有之橄欖石結構係六方最密充電結構且係穩定之結晶結構。因此，上述構成之金屬盒型電池(鋰離子電池)於高溫環境下亦可使用。 又，正極活性物質具有橄欖石結構，且進而，負極活性物質包含經積層之複數個碳層且複數個碳層之平均層間距離為鋰原子之直徑以上。因此，於低溫之狀態下亦可抑制劣化。因此，可知即便將該金屬盒型電池搭載於跨坐型車輛，且於低溫之狀態下金屬盒型電池之充電及放電之頻度變高，亦可抑制金屬盒型電池(鋰離子電池)之劣化。 又，複數個金屬盒型電池之各者係具有金屬製之盒者，該金屬製之盒收容1個正極、1個負極、及電解液或固體電解質。金屬製之盒之散熱性較高。因此，即便於複數個金屬盒型電池之充電時及放電時複數個金屬盒型電池發熱，複數個金屬盒型電池之各者亦進行散熱。藉此，可抑制具有複數個金屬盒型電池之電池組之溫度上升。因此，即便於將具有複數個金屬盒型電池之電池組搭載於跨坐型車輛，且電池組以大電流進行放電之情形時，亦可抑制電池組之溫度上升。其結果，可抑制金屬盒型電池(鋰離子電池)之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制由充電時或放電時之發熱所致之金屬盒型電池(鋰離子電池)之劣化。 進而，複數個金屬盒型電池係藉由金屬盒型電池固定部而相互固定。因此，能夠以考慮到金屬盒型電池之散熱性之佈局，維持複數個金屬盒型電池之位置。例如能夠以於金屬盒型電池彼此之間空出適當之間隙之狀態予以維持。藉此，即便於複數個金屬盒型電池之充電時及放電時複數個金屬盒型電池發熱，亦可抑制電池組之溫度上升。因此，即便於將具有複數個金屬盒型電池之電池組搭載於跨坐型車輛，且電池組以大電流進行放電之情形時，亦可進一步抑制電池組之溫度上升。其結果，可進一步抑制金屬盒型電池(鋰離子電池)之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可進一步抑制由充電時或放電時之發熱所致之金屬盒型電池(鋰離子電池)之劣化。 又，藉由於金屬製之盒收容電解液，即便電解液揮發，金屬製之盒亦不會膨脹。因此，作為電解液，可使用揮發性較高之電解液。揮發性較高之電解液於低溫下不易凝固或凍結。因此，當使用低溫下不易凝固或凍結之電解液時，可於低溫環境下使用具有複數個金屬盒型電池之電池組。因此，即便將具有複數個金屬盒型電池之電池組搭載於跨坐型車輛，且在較搭載於汽車之電瓶更低溫之狀態下進行電池組之充電或大電流之放電，亦可抑制金屬盒型電池之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制由低溫環境下之充電或放電所致之金屬盒型電池(鋰離子電池)之劣化。 如上所述，本發明之電池組係即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制金屬盒型電池(鋰離子電池)之劣化。 (2)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)之構成以外，亦具有以下之構成。 於上述複數個金屬盒型電池之至少1個金屬盒型電池中，上述1個正極、上述1個負極及上述電解液被收容於上述金屬盒型電池，上述電解液係於-20℃不凍結之電解液。 藉由使用於-20℃不凍結之電解液作為電解液，可於-20℃左右之低溫之環境下使用具有複數個金屬盒型電池之電池組。因此，即便將具有複數個金屬盒型電池之電池組搭載於跨坐型車輛，且於-20℃左右之低溫狀態下進行充電或大電流之放電，亦可抑制金屬盒型電池(鋰離子電池)之劣化。由此，即便為搭載於跨坐型車輛之電池組之使用環境，亦可進一步抑制金屬盒型電池(鋰離子電池)之劣化。 (3)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)或(2)之構成以外，亦具有以下之構成。電池組具有殼體部，該殼體部收容上述複數個金屬盒型電池及上述金屬盒型電池固定部之兩者。 根據該構成，電池組所具有之殼體部收容複數個金屬盒型電池及金屬盒型電池固定部。因此，可保護複數個金屬盒型電池免受水或濕氣等之影響。由此，可抑制金屬盒型電池(鋰離子電池)之劣化。因此，即便於將電池組搭載於不具有引擎室或馬達室之跨坐型車輛之情形時，亦可抑制金屬盒型電池(鋰離子電池)之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可進一步抑制金屬盒型電池(鋰離子電池)之劣化。 (4)根據本發明之一態樣，本發明之電池組較佳為除具有上述(3)之構成以外，亦具有以下之構成。電池組具有：1個外部正極端子，其以可自上述殼體部之外部連接(access)之狀態設置於上述殼體部，且與上述複數個金屬盒型電池中之至少1個金屬盒型電池所具有之至少1個上述正極電性連接；及1個外部負極端子，其以可自上述殼體部之外部連接之狀態設置於上述殼體部，且與上述複數個金屬盒型電池中之至少1個金屬盒型電池所具有之至少1個上述負極電性連接。 電池組具有1個外部正極端子及1個外部負極端子。外部正極端子及外部負極端子係以可自殼體部之外部連接之狀態設置於殼體部。因此，可將外部正極端子與外部負極端子連接於電池組供給電力之裝置、或對電池組供給電力之裝置。 (5)根據本發明之一態樣，本發明之電池組較佳為除具有上述(4)之構成以外，亦具有以下之構成。上述殼體部係具有沿著相互交叉之複數個平面分別配置之複數個面之箱體，上述1個外部正極端子及上述1個外部負極端子均設置於上述複數個面中之任一個面。 根據該構成，外部正極端子及外部負極端子設置於殼體部之1個面，故而容易進行將外部正極端子及外部負極端子與外部之裝置連接之作業。 (6)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)至(5)中任一項之構成以外，亦具有以下之構成。上述複數個金屬盒型電池串聯連接成1行。上述金屬盒型電池固定部係將上述複數個金屬盒型電池以串聯連接成1行之狀態加以固定。 根據該構成，電池組所具有之複數個金屬盒型電池係串聯連接成1行。因此，與將相同數量之複數個金屬盒型電池串聯及並聯連接之情形相比，電池組之輸出電壓變高。因此，可一面確保電池組所需之輸出電壓，一面減少電池組所具有之金屬盒型電池之數量。由此，可使電池組小型且輕量。該電池組可使用於電池組所需之輸出電流與容量相對較小且電池組所需之輸出電壓相對較大之使用環境。 (7)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)至(5)中任一項之構成以外，亦具有以下之構成。上述複數個金屬盒型電池構成複數個串聯電池群，該串聯電池群包含相互串聯連接之至少2個金屬盒型電池。上述複數個串聯電池群係相互並聯連接。上述金屬盒型電池固定部係將複數個串聯電池群以並聯連接之狀態加以固定。 根據該構成，電池組具有複數個串聯電池群。複數個串聯電池群之各者包含相互串聯連接之至少2個金屬盒型電池。藉由使構成串聯電池群之金屬盒型電池之數量增加，可使電池組之輸出電壓變高。複數個串聯電池群係相互並聯連接。即，電池組所具有之複數個金屬盒型電池包含相互並聯連接之金屬盒型電池。因此，與電池組所具有之複數個金屬盒型電池串聯連接成1行之情形相比，電池組之輸出電流變大。若電池組之輸出電流變大，則電池組之容量亦變大。相互並聯連接之金屬盒型電池之數量越多，則電池組之輸出電流與容量越大。由於電池組之容量較大，故而可降低電池組之充電頻度。其結果，可抑制金屬盒型電池(鋰離子電池)之劣化。該電池組可使用於電池組所需之輸出電壓、輸出電流及容量相對較大之使用環境。 (8)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)至(5)中任一項之構成以外，亦具有以下之構成。上述複數個金屬盒型電池構成複數個並聯電池群，該並聯電池群包含相互並聯連接之至少2個金屬盒型電池。上述複數個並聯電池群係相互串聯連接。上述金屬盒型電池固定部係將複數個並聯電池群以串聯連接之狀態加以固定。 根據該構成，電池組具有複數個並聯電池群。複數個並聯電池群係相互串聯連接。藉由增加並聯電池群之數量，可使電池組之輸出電壓變高。複數個並聯電池群之各者包含相互並聯連接之至少2個金屬盒型電池。即，電池組所具有之複數個金屬盒型電池包含相互並聯連接之金屬盒型電池。因此，與電池組所具有之複數個金屬盒型電池串聯連接成1行之情形相比，電池組之輸出電流變大。若電池組之輸出電流變大，則電池組之容量亦變大。相互並聯連接之金屬盒型電池之數量越多，則電池組之輸出電流與容量越大。由於電池組之容量較大，故而可降低電池組之充電頻度。其結果，可抑制金屬盒型電池(鋰離子電池)之劣化。該電池組可使用於電池組所需之輸出電壓、輸出電流及容量相對較大之使用環境。 (9)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)至(8)中任一項之構成以外，亦具有以下之構成。電池組可利用12 V～15 V用之直流充電器進行充電。 一般而言，搭載於以引擎作為驅動源之車輛(包含汽車及跨坐型車輛)之鉛蓄電池之輸出電壓係12 V～15 V左右。因此，電池組可利用12 V～15 V用之直流充電器進行充電，藉此，可代替搭載於以引擎作為驅動源之車輛之鉛蓄電池而使用電池組。 (10)根據本發明之一態樣，本發明之電池組較佳為除具有上述(1)至(9)中任一項之構成以外，亦具有以下之構成。電池組可搭載於跨坐型車輛，該跨坐型車輛具備：至少1個前輪；至少1個後輪；及驅動源，其至少一部分於車輛前後方向上配置於較上述至少1個前輪更靠後方。 ＜用語之定義＞ 於本發明中，所謂「複數個金屬盒型電池之各者係與複數個金屬盒型電池中之任一者串聯連接」，並非意圖使複數個金屬盒型電池之各者與同一金屬盒型電池串聯連接。複數個金屬盒型電池之各者既可與同一金屬盒型電池串聯連接，亦可不與同一金屬盒型電池串聯連接。例如，假定複數個金屬盒型電池包含第1～第3金屬盒型電池之情形。設為第1金屬盒型電池與第2金屬盒型電池串聯連接，第3金屬盒型電池與第4金屬盒型電池串聯連接。於此情形時，第1金屬盒型電池既可與第3金屬盒型電池及第4金屬盒型電池串聯連接，亦可不與第3金屬盒型電池及第4金屬盒型電池串聯連接。 於本發明中，所謂「複數個金屬盒型電池之各者係與複數個金屬盒型電池中之任一者串聯連接」，並非意圖使複數個金屬盒型電池之各者所串聯連接之金屬盒型電池之數量為1個。複數個金屬盒型電池之各者所串聯連接之金屬盒型電池之數量可為1個，亦可為2個以上。 於本發明中，所謂「電解液」係於溶劑中溶解有電解質者，於電池(cell)內以液體形式存在。溶解於溶劑之電解質中所不包含固體電解質。「固體電解質」係於電池內以凝膠形態或固體形態存在之電解質。 於本發明中，所謂「碳」係於藉由自含碳之原料釋放除碳以外之元素而生成含碳率較高之物質之製程中所獲得之物質。該製程係稱為所謂之碳化。將藉由碳化而獲得之物質於高溫下進行熱處理，藉此，碳層之積層結構發達而可獲得石墨。石墨係指具有將碳六元環二維地鍵結而成之層積層而得之積層結構且於該積層結構中層間距離為3.35埃以下者。本發明中之「碳」係成為石墨之前之物質。於本發明中，「碳」不包含石墨。 於本發明中，所謂「層間距離」係相鄰之層與層之間之距離。於本發明中，所謂「平均層間距離」係相鄰之層與層之間之距離之平均值。 於本發明中，所謂「於-20℃不凍結之電解液」係指於-20℃之大氣壓下不凍結之電解液。大氣壓係根據標高而變化。「於-20℃不凍結之電解液」係只要於任一標高下在-20℃之大氣壓下不凍結，則亦可於某一標高下在-20℃之大氣壓下凍結。 於本發明中，所謂「外部正極端子可自殼體部之外部連接之狀態」係可於由電池組供給電力之裝置電性連接外部正極端子之狀態。所謂「外部負極端子可自殼體部之外部連接之狀態」係可於對電池組供給電力之裝置電性連接外部負極端子之狀態。 於本發明中，所謂「與至少1個金屬盒型電池分別具有之至少1個正極電性連接之1個外部正極端子」係指1個外部正極端子不經由電池組所具有之任一個金屬盒型電池而與上述至少1個正極連接之狀態。本發明中之「與至少1個金屬盒型電池分別具有之至少1個負極電性連接之1個外部負極端子」之定義亦相同。 於本發明中，所謂「沿著相互交叉之複數個平面分別配置之複數個面」係指複數個面與複數個平面分別平行或大致平行之狀態。複數個面之各者只要整體上沿著任一個平面，則亦可具有平緩之曲面或凹凸。 於本發明中，所謂「複數個金屬盒型電池串聯連接成1行」係只要複數個金屬盒型電池串聯地電性連接成1行，則複數個金屬盒型電池可排列成一列，亦可不排列成一列。 於本發明中，「包含相互並聯連接之至少2個金屬盒型電池之並聯電池群」僅由相互並聯連接之至少2個金屬盒型電池構成。即，構成並聯電池群之金屬盒型電池彼此並不串聯連接。構成並聯電池群之金屬盒型電池亦可與不包含於該並聯電池群中之金屬盒型電池串聯連接。 於本發明中，「包含相互串聯連接之至少2個金屬盒型電池之串聯電池群」僅由相互串聯連接之至少2個金屬盒型電池構成。即，構成串聯電池群之金屬盒型電池彼此並不並聯連接。構成串聯電池群之金屬盒型電池亦可與不包含於該串聯電池群中之金屬盒型電池並聯連接。 所謂「跨坐型車輛」係指騎乘者以如跨坐於鞍部之狀態乘坐之所有車輛。本發明中之跨坐型車輛包含機車、附原動機之機車、附踏板之輕型機車、三輪車、四輪越野車(ATV：All Terrain Vehicle(全地形型車輛))。跨坐型車輛中所包含之機車包含速克達、附原動機之機車、附踏板之輕型機車等。 於本發明中，所謂跨坐型車輛之「車輛前後方向」係指當駕駛者乘坐於直立於水平之路面之狀態之車輛之情形時由駕駛者觀察到之前後方向。 於本發明/說明書中，所謂複數個選擇項中之至少1個(一者)，包含自複數個選擇項想到之全部組合。所謂複數個選擇項中之至少1個(一者)，可為複數個選擇項中之任一個，亦可為複數個選擇項之全部。例如，所謂A、B及C中之至少1個可僅為A，亦可僅為B，亦可僅為C，亦可為A與B，亦可為A與C，亦可為B與C，且亦可為A、B及C。 本發明之電池組亦可具有複數個於申請專利範圍中未特定出數量而於翻譯成英語之情形時以單數表示之要素。本發明之電池組亦可僅具有一個於申請專利範圍中未特定出數量而於翻譯成英語之情形時以單數表示之要素。 於本說明書中，例如有如「1～10」及「1至10」般，使用「～」或「至」表示數值範圍之情形。於本說明書中，「1～10」及「1至10」均意味著1以上且10以下。 於本發明中，包含(including)、具有(comprising)、具備(having)及其等之衍生語係以除了包含所列舉之項及其等效物以外亦包含追加項在內之意圖而使用。 於本發明中，被安裝(mounted)、被連接(connected)、被結合(coupled)、被支持(supported)此種用語係廣義地使用。具體而言，不僅包含直接之安裝、連接、結合、支持，亦包含間接之安裝、連接、結合及支持。進而，被連接(connected)及被結合(coupled)並不限於物理性或機械性之連接/結合。其等亦包含直接或間接之電性連接/結合。 只要未被另外定義，則本說明書中使用之全部用語(包含技術用語及科學用語)具有與由本發明所屬領域內之技術人員通常所理解之含義相同之含義。如由通常使用之辭典定義之用語般之用語應解釋為具有與相關技術及本發明之上下文中之含義一致之含義，而不應以理想化或過度形式化之含義進行解釋。 於本說明書中，「較佳」此種用語為非排他性之用語。「較佳」意味著「較佳但不限於此」。於本說明書中，記載為「較佳」之構成至少發揮藉由上述(1)之構成而獲得之上述效果。又，於本說明書中，「亦可」此種用語為非排他性之用語。「亦可」意味著「亦可但不限於此」。於本說明書中，記載為「亦可」之構成至少發揮藉由上述(1)之構成而獲得之上述效果。 於本發明中，並不限制將上述較佳之構成相互組合。於詳細說明本發明之實施形態之前，應理解本發明並不受以下說明中記載或圖式中圖示之構成要素之構成及配置之詳情所限制。本發明亦可為除下述實施形態以外之實施形態。本發明亦可為對下述實施形態施加各種變更而得之實施形態。又，本發明可將下述變化例適當組合後實施。 [發明之效果] 本發明之電池組係即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制鋰離子電池之劣化。[Inventors of the Invention] The inventors of the present invention have studied that a lithium ion battery pack as described in Patent Document 1 is mounted on a straddle type vehicle such as a locomotive instead of a lead storage battery. As a result, it is clear that the lithium ion battery is deteriorated due to the use environment of the straddle type vehicle. The present invention provides a battery pack that can suppress deterioration of a lithium ion battery even in a use environment of a battery pack mounted on a straddle type vehicle. [Technical means for solving the problem] The inventors of the present invention conducted a comparative study on the use environment of the lead storage battery mounted on the straddle type vehicle and the use environment of the lead storage battery mounted on the automobile (four-wheeled vehicle). In a straddle-type vehicle that uses an engine as a driving source and a vehicle that uses an engine as a driving source, the lead storage battery is discharged at a large current to start the driving of the starting motor when the engine is started. In a straddle type vehicle using a motor as a driving source and a motor using a motor as a driving source, the lead storage battery is discharged at a large current during traveling to drive the starter motor. A car with an engine as a driving source has an engine room for housing an engine. Further, a car having a motor as a drive source is provided with a motor chamber for housing a motor. The lead storage battery installed in the automobile is housed in an engine room or a motor room. Therefore, even in a low-temperature environment such as at night in winter, the temperature of the lead storage battery installed in the automobile is less likely to become extremely cold. In contrast, a straddle type vehicle does not have an engine room or a motor room. The lead storage battery mounted on the straddle type vehicle is disposed in a state of being exposed to the outside or being covered only by the vehicle body casing. Therefore, in a low-temperature environment such as the night of winter, the temperature of the lead storage battery mounted on the straddle type vehicle is drastically lowered. Therefore, the lead storage battery mounted on the straddle type vehicle tends to discharge a large current in a state where it is lower than the lead storage battery mounted on the automobile. Moreover, the straddle type vehicle requires a lighter and smaller size of the vehicle than the automobile. A lead storage battery of a straddle type vehicle using an engine as a driving source can be used with a smaller weight and a smaller volume than a lead storage battery mounted on a vehicle using an engine as a driving source. In other words, the lead storage battery mounted on the straddle type vehicle using the engine as the drive source has a smaller capacity than the lead storage battery mounted on the automobile using the engine as the drive source. In addition, a lead storage battery mounted on a straddle type vehicle using a motor as a drive source can be used with a smaller weight and a smaller volume than a lead storage battery mounted on a motor using a motor as a drive source. In other words, the lead storage battery mounted on the straddle type vehicle using the motor as the drive source has a smaller capacity than the lead storage battery mounted on the automobile using the motor as the drive source. As described above, the lead storage battery mounted on the straddle type vehicle has a smaller capacity than the lead storage battery mounted on the automobile. Therefore, the lead storage battery mounted on the straddle type vehicle tends to be more frequently charged than the lead storage battery mounted on the automobile. Therefore, the lead storage battery mounted on the straddle type vehicle tends to be charged more frequently than the lead storage battery mounted on the automobile in a state where it is cooler than the lead storage battery installed in the automobile. As described above, the inventors of the present invention have found that a lead storage battery mounted on a straddle type vehicle tends to discharge a large current in a state of being cooler than a lead storage battery mounted in an automobile, and is more expensive than a lead storage battery mounted in a vehicle. In the low temperature state, the lead storage battery mounted in the automobile tends to be charged more frequently. The inventors of the present invention have studied the lithium ion battery pack described in Patent Document 1 in place of a lead storage battery in a straddle type vehicle. However, it is noted that the environment in which the lead storage battery mounted on the straddle-type vehicle is used is the environment as described above. Therefore, when the lithium ion battery pack described in Patent Document 1 is mounted on a straddle type vehicle, the lithium ion battery is used. It is easy to deteriorate. The inventors of the present invention have studied the charging and discharging of a lithium ion battery having a positive electrode active material containing lithium iron phosphate and a graphite-based negative electrode active material described in Patent Document 1 in a low temperature state. As a result, the following is known. It can be seen that a lithium ion battery can realize a discharge of a large current required for a straddle type vehicle even in a low temperature environment. Further, it is understood that when the lithium ion battery is slowly charged, it is difficult to deteriorate the lithium ion battery even if the discharge is repeated in a low temperature environment. However, it is understood that the lithium ion battery is liable to be deteriorated when the lithium ion battery is repeatedly charged in a low temperature environment. The negative electrode having a graphite-based negative electrode active material has a crystal structure in which a carbon graphite (graphite) layer is laminated. When the lithium ion battery is charged, the lithium ions move from the positive electrode to the negative electrode and enter between the laminated graphite layers in the negative electrode. On the other hand, when the lithium ion battery is discharged, lithium ions are separated from the graphite layer in the negative electrode and move toward the positive electrode. In the negative electrode, the distance between the graphite layers is slightly smaller than the diameter of the lithium atoms. Therefore, when lithium ions enter between the graphite layers in the negative electrode when the lithium ion battery is charged, the graphite layers are widened. On the other hand, when lithium ions are separated from the graphite layer when the lithium ion battery is discharged, the graphite layers are narrowed. When the charging and discharging of the lithium ion battery are repeated, the lithium ions repeatedly enter and exit between the graphite layers, so that the gap between the graphite layers is expanded and reduced. As a result, the state of the layer of the graphite layer changes. Therefore, it is understood that the crystal structure of the negative electrode largely changes. It can be seen that this is one of the main causes of deterioration of the negative electrode. The inventors of the present invention have studied the use of an anode active material having a plurality of laminated carbon layers in a negative electrode of a lithium ion battery instead of using a negative electrode active material having a plurality of laminated graphite layers. The carbon here is non-graphite. More specifically, the negative electrode active material having a plurality of carbon layers as the negative electrode active material and having an average interlayer distance of at least the diameter of lithium ions has been studied. As a result, the following is known. The average interlayer distance of the plurality of carbon layers is equal to or larger than the diameter of the lithium ions. Therefore, even when lithium ions enter between the adjacent carbon layers of the negative electrode during charging of the lithium ion battery, the adjacent carbon layers are hardly widened. Moreover, even when lithium ions are separated from adjacent carbon layers during discharge of the lithium ion battery, the distance between adjacent carbon layers does not change much. That is, even when lithium ions enter and exit the carbon layer during charging and discharging, the average interlayer distance of the plurality of carbon layers hardly changes. Therefore, the laminated state of the plurality of carbon layers hardly changes. Thereby, it is understood that the crystal structure of the negative electrode does not change much. Therefore, it is understood that deterioration of the negative electrode can be suppressed. Therefore, it is understood that deterioration of the lithium ion battery having the negative electrode can be suppressed. Further, it has been found that since the negative electrode has the above configuration, deterioration of the lithium ion battery can be suppressed even if the frequency of charging and discharging of the lithium ion battery is increased. Further, it has been found that since the negative electrode has the above-described configuration, even if the lithium ion battery having the negative electrode is charged or discharged in a low temperature state, deterioration can be suppressed. Therefore, it is understood that even if the lithium ion battery is mounted on a straddle type vehicle and the frequency of charging and discharging of the lithium ion battery is high in a low temperature state, deterioration of the lithium ion battery can be suppressed. Based on the above findings, the inventors of the present invention have completed the present invention. Hereinafter, the present invention will be described. (1) The battery pack of the present invention has a plurality of lithium ion batteries electrically connected to each other, and each of the plurality of lithium ion batteries is a metal box type battery, and has: one positive electrode; one negative electrode; Or a solid electrolyte; and a metal case for accommodating the one positive electrode, the one negative electrode, and the electrolyte or solid electrolyte; and each of the plurality of metal battery cells and the plurality of metal battery cells Any one of the above-mentioned positive electrodes having an olivine structure, the negative electrode having a negative electrode active material, the negative electrode active material comprising a plurality of laminated carbon layers, and an average interlayer distance of the plurality of carbon layers being lithium The battery pack has a metal case type battery fixing portion, and the metal case type battery fixing portion fixes the plurality of metal case type batteries to each other. According to this configuration, each of the plurality of metal box type batteries is connected in series to any of a plurality of metal box type batteries. The greater the number of metal box type batteries connected in series, the higher the output voltage of the battery pack. By increasing the number of metal-cassette batteries connected in series to each other, the battery pack can be used in an environment where a higher output voltage is required. The metal box type battery is a lithium ion battery. Lithium-ion batteries have lower weight energy density and volumetric energy density than lead batteries. Therefore, when a battery pack having a plurality of lithium ion batteries is mounted on a straddle type vehicle instead of the lead storage battery, the capacity of the battery can be maintained, and the straddle type vehicle can be made lighter and smaller. Alternatively, the capacity of the battery can be increased without increasing the size and weight of the straddle type vehicle. By additionally increasing the capacity of the battery pack, the burden on each of the plurality of metal-cassette batteries of the battery pack is reduced, so that deterioration of the metal-cassette battery can be suppressed. Each of a plurality of metal box type batteries (lithium ion batteries) has one positive electrode, one negative electrode, and an electrolyte or a solid electrolyte. The negative electrode of the metal box type battery includes a negative electrode active material containing a carbon layer instead of a graphite layer, and an average interlayer distance of the plurality of carbon layers is equal to or larger than a diameter of the lithium atom. Since the average interlayer distance of the plurality of carbon layers is greater than the diameter of the lithium ions, even if the lithium ions enter between the adjacent carbon layers of the negative electrode during charging of the metal box type battery, the adjacent carbon layers are hardly expanded. width. Further, even when lithium metal ions are separated from adjacent carbon layers during discharge of the metal-casing type battery, the distance between adjacent carbon layers does not change much. That is, even when lithium metal ions enter and exit the carbon layer during charging of the metal-cassette type battery and during discharge, the average interlayer distance of the plurality of carbon layers hardly changes. Therefore, the laminated state of the carbon layer hardly changes. Thereby, the crystal structure of the negative electrode does not change much. Therefore, deterioration of the negative electrode can be suppressed. Therefore, the metal box type battery having the negative electrode can suppress deterioration. Therefore, deterioration of the metal cassette type battery having the negative electrode can be suppressed. Moreover, since the negative electrode has the above configuration, even if the frequency of charging and discharging of the metal-cassette battery is increased, deterioration of the metal-cassette battery can be suppressed. Further, since the negative electrode has the above-described configuration, the metal-cassette battery having the negative electrode can suppress deterioration even in a low temperature state. Therefore, even if the metal box type battery is mounted on a straddle type vehicle, and the frequency of charging and discharging of the metal box type battery is high in a low temperature state, deterioration of the metal box type battery (lithium ion battery) can be suppressed. Further, since the positive electrode of the metal cartridge type battery includes the positive electrode active material having an olivine structure, the metal cartridge type battery (lithium ion battery) is not easily deteriorated even if charging and discharging are repeated. Therefore, even if the charging and discharging of the metal case type battery are repeated in a low temperature environment, the metal case type battery (lithium ion battery) is not easily deteriorated. Therefore, even if a battery pack having a plurality of metal-cassette batteries is mounted on a straddle-type vehicle and charging and discharging of the battery pack are repeated relatively frequently, deterioration of the metal-cassette battery (lithium ion battery) can be suppressed. In other words, even in the environment in which the battery pack mounted on the straddle-type vehicle is used, deterioration of the metal-cassette battery (lithium ion battery) can be suppressed. Further, the olivine structure of the positive electrode active material is a hexagonal most densely charged structure and is a stable crystal structure. Therefore, the metal box type battery (lithium ion battery) having the above configuration can also be used in a high temperature environment. Further, the positive electrode active material has an olivine structure, and further, the negative electrode active material includes a plurality of laminated carbon layers, and the average interlayer distance of the plurality of carbon layers is equal to or larger than the diameter of the lithium atoms. Therefore, deterioration can be suppressed even in a low temperature state. Therefore, it is understood that even if the metal cassette type battery is mounted on a straddle type vehicle and the frequency of charging and discharging of the metal cassette type battery is high in a low temperature state, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. . Further, each of the plurality of metal-cassette batteries has a metal case, and the metal case houses one positive electrode, one negative electrode, and an electrolytic solution or a solid electrolyte. The metal case has a high heat dissipation. Therefore, even when a plurality of metal case type batteries are charged during charging and discharging, a plurality of metal case type batteries are also radiated. Thereby, the temperature rise of the battery pack having a plurality of metal cassette type batteries can be suppressed. Therefore, even when a battery pack having a plurality of metal-cassette batteries is mounted on a straddle-type vehicle and the battery pack is discharged with a large current, the temperature rise of the battery pack can be suppressed. As a result, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. In other words, even in the use environment of the battery pack mounted on the straddle type vehicle, deterioration of the metal case type battery (lithium ion battery) due to heat generation during charging or discharging can be suppressed. Further, a plurality of metal box type batteries are fixed to each other by a metal box type battery fixing portion. Therefore, the position of a plurality of metal-cassette batteries can be maintained in consideration of the layout of the heat dissipation of the metal-cassette type battery. For example, it can be maintained in a state in which the metal box type batteries are provided with a proper gap therebetween. Thereby, even when a plurality of metal-cassette batteries are charged during charging and discharging, the temperature of the battery pack can be suppressed from rising. Therefore, even when a battery pack having a plurality of metal-cassette batteries is mounted on a straddle-type vehicle and the battery pack is discharged with a large current, the temperature rise of the battery pack can be further suppressed. As a result, deterioration of the metal cassette type battery (lithium ion battery) can be further suppressed. In other words, even in the environment in which the battery pack mounted on the straddle-type vehicle is used, deterioration of the metal-cassette battery (lithium ion battery) due to heat generation during charging or discharging can be further suppressed. Further, since the electrolytic solution is accommodated in the metal case, the metal case does not expand even if the electrolytic solution is volatilized. Therefore, as the electrolytic solution, an electrolyte having a high volatility can be used. The electrolyte with higher volatility is less likely to solidify or freeze at low temperatures. Therefore, when an electrolyte which is hard to solidify or freeze at a low temperature is used, a battery pack having a plurality of metal cartridge type batteries can be used in a low temperature environment. Therefore, even if a battery pack having a plurality of metal-cassette batteries is mounted on a straddle-type vehicle, and charging of a battery pack or discharge of a large current is performed in a state where the battery is mounted at a lower temperature than the battery mounted in the automobile, the metal case can be suppressed. Deterioration of the battery. In other words, even in the environment in which the battery pack mounted on the straddle type vehicle is used, deterioration of the metal case type battery (lithium ion battery) caused by charging or discharging in a low temperature environment can be suppressed. As described above, the battery pack of the present invention can suppress the deterioration of the metal-cassette battery (lithium ion battery) even in the use environment of the battery pack mounted on the straddle-type vehicle. (2) According to an aspect of the invention, the battery pack of the present invention preferably has the following constitution in addition to the configuration of the above (1). In at least one metal cassette type battery of the plurality of metal cassette type batteries, the one positive electrode, the one negative electrode, and the electrolytic solution are housed in the metal cassette type battery, and the electrolytic solution is not frozen at -20 ° C The electrolyte. By using an electrolyte which is not frozen at -20 ° C as an electrolyte, a battery pack having a plurality of metal cartridge type batteries can be used in a low temperature environment of about -20 ° C. Therefore, even if a battery pack having a plurality of metal-cassette batteries is mounted on a straddle-type vehicle and charged or discharged at a low temperature of about -20 ° C, the metal-cassette battery (lithium-ion battery) can be suppressed. Deterioration. Thereby, even in the use environment of the battery pack mounted in the straddle type vehicle, deterioration of the metal box type battery (lithium ion battery) can be further suppressed. (3) According to an aspect of the invention, the battery pack of the present invention preferably has the following constitution in addition to the configuration of the above (1) or (2). The battery pack has a casing portion that accommodates both of the plurality of metal box type batteries and the metal box type battery fixing portion. According to this configuration, the casing portion of the battery pack houses a plurality of metal box type batteries and metal box type battery fixing portions. Therefore, a plurality of metal box type batteries can be protected from water or moisture. Thereby, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. Therefore, even when the battery pack is mounted on a straddle type vehicle that does not have an engine room or a motor room, deterioration of the metal box type battery (lithium ion battery) can be suppressed. In other words, even in the environment in which the battery pack mounted on the straddle type vehicle is used, deterioration of the metal box type battery (lithium ion battery) can be further suppressed. (4) According to an aspect of the present invention, the battery pack of the present invention preferably has the following constitution in addition to the configuration of the above (3). The battery pack includes: one outer positive terminal that is provided in the housing portion in a state accessible from an outer portion of the housing portion, and at least one metal cassette type of the plurality of metal cassette type batteries At least one of the positive electrodes is electrically connected to the battery; and one external negative terminal is provided in the casing portion in a state connectable from the outside of the casing portion, and is connected to the plurality of metal-cassette batteries At least one of the above-mentioned negative electrodes included in at least one of the metal battery cells is electrically connected. The battery pack has one external positive terminal and one external negative terminal. The external positive electrode terminal and the external negative electrode terminal are provided in the casing portion in a state of being connectable from the outside of the casing portion. Therefore, the external positive terminal and the external negative terminal can be connected to a device for supplying electric power to the battery pack or a device for supplying electric power to the battery pack. (5) According to an aspect of the invention, the battery pack of the present invention preferably has the following constitution in addition to the configuration of the above (4). The casing portion has a casing having a plurality of surfaces arranged along a plurality of planes intersecting each other, and the one outer positive terminal and the one outer negative terminal are provided on one of the plurality of surfaces. According to this configuration, since the external positive electrode terminal and the external negative electrode terminal are provided on one surface of the casing portion, it is easy to connect the external positive electrode terminal and the external negative electrode terminal to an external device. (6) The battery pack of the present invention preferably has the following constitution in addition to the configuration of any one of the above (1) to (5). The above plurality of metal box type batteries are connected in series in one row. In the above-described metal box type battery fixing portion, the plurality of metal box type batteries are fixed in a state of being connected in series in a row. According to this configuration, the plurality of metal box type batteries included in the battery pack are connected in series in one line. Therefore, the output voltage of the battery pack becomes higher than when a plurality of metal-cassette batteries of the same number are connected in series and in parallel. Therefore, the number of metal-cassette batteries of the battery pack can be reduced while ensuring the output voltage required for the battery pack. Thereby, the battery pack can be made compact and lightweight. The battery pack can be used in an environment where the output current and capacity required for the battery pack are relatively small and the output voltage required for the battery pack is relatively large. (7) The battery pack of the present invention preferably has the following constitution in addition to the configuration of any one of the above (1) to (5). The plurality of metal box type batteries constitute a plurality of series battery groups, and the series battery group includes at least two metal box type batteries connected in series to each other. The plurality of series battery groups are connected in parallel with each other. The metal box type battery fixing portion fixes a plurality of series battery groups in a state of being connected in parallel. According to this configuration, the battery pack has a plurality of battery cells in series. Each of the plurality of series battery packs includes at least two metal box type batteries connected in series to each other. By increasing the number of metal cartridge type batteries constituting the series battery group, the output voltage of the battery pack can be made high. A plurality of series battery groups are connected in parallel with each other. That is, the plurality of metal box type batteries included in the battery pack include metal box type batteries connected in parallel to each other. Therefore, the output current of the battery pack becomes larger as compared with the case where a plurality of metal box type batteries of the battery pack are connected in series in one line. If the output current of the battery pack becomes large, the capacity of the battery pack also becomes large. The greater the number of metal box type batteries connected in parallel with each other, the larger the output current and capacity of the battery pack. Since the capacity of the battery pack is large, the charging frequency of the battery pack can be reduced. As a result, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. The battery pack can be used in a battery environment where the output voltage, output current, and capacity required for the battery pack are relatively large. (8) The battery pack of the present invention preferably has the following constitution in addition to the configuration of any one of the above (1) to (5). The plurality of metal cassette type batteries constitute a plurality of parallel battery groups, and the parallel battery group includes at least two metal box type batteries connected in parallel with each other. The plurality of parallel battery groups are connected to each other in series. The metal box type battery fixing portion fixes a plurality of parallel battery groups in a state of being connected in series. According to this configuration, the battery pack has a plurality of parallel battery groups. A plurality of parallel battery groups are connected in series with each other. By increasing the number of parallel battery groups, the output voltage of the battery pack can be made higher. Each of the plurality of parallel battery groups includes at least two metal box type batteries connected in parallel with each other. That is, the plurality of metal box type batteries included in the battery pack include metal box type batteries connected in parallel to each other. Therefore, the output current of the battery pack becomes larger as compared with the case where a plurality of metal box type batteries of the battery pack are connected in series in one line. If the output current of the battery pack becomes large, the capacity of the battery pack also becomes large. The greater the number of metal box type batteries connected in parallel with each other, the larger the output current and capacity of the battery pack. Since the capacity of the battery pack is large, the charging frequency of the battery pack can be reduced. As a result, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. The battery pack can be used in a battery environment where the output voltage, output current, and capacity required for the battery pack are relatively large. (9) According to an aspect of the invention, the battery pack of the present invention preferably has the following constitution in addition to the configuration of any one of the above (1) to (8). The battery pack can be charged with a DC charger for 12 V to 15 V. In general, the output voltage of a lead-acid battery mounted on a vehicle that uses an engine as a driving source (including a car and a straddle-type vehicle) is about 12 V to 15 V. Therefore, the battery pack can be charged by the DC charger for 12 V to 15 V, whereby the battery pack can be used instead of the lead storage battery mounted on the vehicle using the engine as the drive source. (10) The battery pack of the present invention preferably has the following constitution in addition to the configuration of any one of the above (1) to (9). The battery pack can be mounted on a straddle-type vehicle including: at least one front wheel; at least one rear wheel; and a drive source, at least a part of which is disposed in the vehicle front-rear direction at least one of the front wheels rear. <Definition of Terms> In the present invention, "each of a plurality of metal-cassette batteries is connected in series to any of a plurality of metal-cassette batteries", and it is not intended to make each of a plurality of metal-cassette batteries Connected in series with the same metal box type battery. Each of the plurality of metal box type batteries may be connected in series to the same metal box type battery or may not be connected in series to the same metal box type battery. For example, it is assumed that a plurality of metal case type batteries include the first to third metal case type batteries. The first metal box type battery is connected in series to the second metal box type battery, and the third metal box type battery is connected in series to the fourth metal box type battery. In this case, the first metal battery can be connected in series to the third metal battery and the fourth metal battery, or not connected to the third metal battery and the fourth metal battery. In the present invention, "each of the plurality of metal-cassette batteries is connected in series to any of a plurality of metal-cassette batteries", and is not intended to connect the metal of the plurality of metal-cassette batteries in series. The number of box type batteries is one. The number of the metal box type batteries in which the plurality of metal box type batteries are connected in series may be one or two or more. In the present invention, the "electrolyte" is one in which a electrolyte is dissolved in a solvent and is present in a liquid form in a cell. The solid electrolyte is not contained in the electrolyte dissolved in the solvent. The "solid electrolyte" is an electrolyte which exists in a gel form or a solid form in a battery. In the present invention, the "carbon" is a substance obtained by a process of producing a substance having a high carbon content by releasing an element other than carbon from a raw material containing carbon. This process is called so-called carbonization. The material obtained by carbonization is heat-treated at a high temperature, whereby the laminated structure of the carbon layer is developed to obtain graphite. Graphite refers to a laminated structure having a laminated layer in which a carbon six-membered ring is two-dimensionally bonded, and the interlayer distance in the laminated structure is 3.35 Å or less. The "carbon" in the present invention is a substance before graphite. In the present invention, "carbon" does not contain graphite. In the present invention, the "interlayer distance" is the distance between adjacent layers and layers. In the present invention, the "average interlayer distance" is an average value of the distance between adjacent layers and layers. In the present invention, the "electrolyte which does not freeze at -20 ° C" means an electrolyte which does not freeze at atmospheric pressure of -20 ° C. The atmospheric pressure varies according to the elevation. The "electrolyte that does not freeze at -20 ° C" can be frozen at a certain elevation at a pressure of -20 ° C as long as it does not freeze at any elevation at -20 ° C. In the present invention, the state in which the external positive terminal can be connected from the outside of the casing portion is a state in which the external positive terminal can be electrically connected to the device that supplies electric power from the battery pack. The "state in which the external negative terminal can be connected from the outside of the casing portion" is a state in which the external negative terminal can be electrically connected to the device that supplies electric power to the battery pack. In the present invention, the term "one external positive terminal electrically connected to at least one positive electrode of at least one metal-box type battery" means that one external positive terminal does not pass through any one of the metal cases. The battery is connected to the at least one positive electrode. In the present invention, the definition of "one external negative terminal electrically connected to at least one negative electrode of at least one metal-box type battery" is also the same. In the present invention, the phrase "a plurality of planes arranged along a plurality of planes intersecting each other" means a state in which a plurality of planes and a plurality of planes are parallel or substantially parallel, respectively. Each of the plurality of faces may have a gentle curved surface or unevenness as long as it is along any of the planes as a whole. In the present invention, the "multiple metal box type batteries are connected in series in one line" means that as long as a plurality of metal box type batteries are electrically connected in series to one line, a plurality of metal box type batteries may be arranged in a row or not. Arrange in a column. In the present invention, the "parallel battery group including at least two metal cassette type batteries connected in parallel with each other" is composed only of at least two metal box type batteries connected in parallel to each other. That is, the metal cartridge type batteries constituting the parallel battery group are not connected to each other in series. The metal case type battery constituting the parallel battery group may be connected in series to the metal case type battery not included in the parallel battery group. In the present invention, the "series battery group including at least two metal cartridge type batteries connected in series" is composed of at least two metal cartridge type batteries connected in series to each other. That is, the metal cartridge type batteries constituting the series battery group are not connected to each other in parallel. The metal case type battery constituting the series battery group may be connected in parallel to the metal case type battery not included in the series battery group. The term "straddle-type vehicle" means all the vehicles that the rider rides in such a state as to sit on the saddle. The straddle type vehicle of the present invention includes a locomotive, a locomotive with a prime mover, a light locomotive with a pedal, a tricycle, and a four-wheeled off-road vehicle (ATV: All Terrain Vehicle). The locomotives included in the straddle-type vehicle include a speed skating, a locomotive with a prime mover, and a light locomotive with a pedal. In the present invention, the "vehicle front and rear direction" of the straddle type vehicle refers to the front and rear directions observed by the driver when the driver rides on the vehicle in a state of standing on a horizontal road surface. In the present invention/in the specification, at least one of the plurality of selection items includes one or all of the combinations selected from the plurality of selection items. At least one (one) of the plurality of selection items may be any one of a plurality of selection items, or may be all of a plurality of selection items. For example, at least one of A, B, and C may be only A, may be only B, may be only C, may be A and B, may be A and C, or may be B and C. And can also be A, B and C. The battery pack of the present invention may also have a plurality of elements singularly expressed in the case where the number is not specified in the scope of the patent application and is translated into English. The battery pack of the present invention may also have only one element which is not indicated in the scope of the patent application and is expressed in the singular in the case of translation into English. In the present specification, for example, "1 to 10" and "1 to 10" are used, and "~" or "to" is used to indicate a numerical range. In the present specification, "1 to 10" and "1 to 10" mean 1 or more and 10 or less. In the present invention, the terms "including", "comprising", "having", and the like, are used in addition to the inclusion of the recited items and their equivalents. In the present invention, the terms mounted, connected, coupled, and supported are used broadly. Specifically, it includes not only direct installation, connection, integration, support, but also indirect installation, connection, integration and support. Further, connected and coupled are not limited to physical or mechanical connections/combinations. They also include direct or indirect electrical connections/bonding. All terms (including technical terms and scientific terms) used in the specification have the same meaning as commonly understood by those skilled in the art to which the invention belongs, unless otherwise defined. Terms such as those defined by the commonly used dictionary should be interpreted as having meaning consistent with the meaning of the related art and the context of the present invention, and should not be interpreted in terms of idealization or over-formalization. In this specification, the term "better" is a non-exclusive term. "Better" means "better but not limited to". In the present specification, the configuration described as "preferred" exhibits at least the above-described effects obtained by the configuration of the above (1). Also, in the present specification, the term "may be" is a non-exclusive term. "Also" means "may but not limited to". In the present specification, the configuration described as "may" is at least the above-described effect obtained by the configuration of the above (1). In the present invention, the above preferred compositions are not limited to each other. The present invention is not limited by the details of the configuration and arrangement of the components shown in the following description. The present invention may be an embodiment other than the following embodiments. The present invention can also be embodied in various modifications of the embodiments described below. Further, the present invention can be carried out by appropriately combining the following modifications. [Effect of the Invention] The battery pack of the present invention can suppress the deterioration of the lithium ion battery even in the use environment of the battery pack mounted on the straddle type vehicle.

＜本發明之實施形態＞ 以下，一面參照圖1，一面對本發明之實施形態之電池組16進行說明。電池組16具有相互連接之複數個金屬盒型電池161。複數個金屬盒型電池161之各者係與複數個金屬盒型電池161中之任一者串聯連接。複數個金屬盒型電池161之各者亦可與複數個金屬盒型電池161中之任一個金屬盒型電池161串聯連接。複數個金屬盒型電池161之各者亦可與複數個金屬盒型電池161中之2個以上之金屬盒型電池161串聯連接。 複數個金屬盒型電池161之各者係如下之金屬盒型電池，即具有：1個正極；1個負極；電解液或固體電解質；及金屬製之盒，其收容1個正極、1個負極及電解液。正極具有橄欖石結構之正極活性物質。負極具有負極活性物質，該負極活性物質包含複數個碳層16121a、16121b、16121c且複數個碳層之平均層間距離為鋰原子之直徑以上。圖1中例示出於相鄰之2層碳層16121a、16121b之間存在鋰原子之情形。又，例示出於相鄰之2層碳層16121b、16121c之間存在鋰原子之情形。於圖1中，將鋰原子之直徑表示為D。又，將相鄰之2個碳層16121a、16121b之間之距離表示為L。有時亦將相鄰之2個碳層16121a、16121b之間之距離稱為相鄰之2個碳層16121a、16121b之層間距離。於圖1中，例示出相鄰之2個碳層16121a、16121b之間之距離L大於鋰原子之直徑D之情形。 電池組16具有金屬盒型電池固定部，該金屬盒型電池固定部係以將複數個金屬盒型電池161之各者與串聯連接之金屬盒型電池161固定之方式，將複數個金屬盒型電池161相互固定。 根據該構成，複數個金屬盒型電池161之各者係與複數個金屬盒型電池161中之任一者串聯連接。相互串聯連接之金屬盒型電池161之數量越多，則電池組16之輸出電壓越高。藉由使相互串聯連接之金屬盒型電池161之數量變多，可於需要較高之輸出電壓之使用環境中使用電池組16。 金屬盒型電池161係鋰離子電池。鋰離子電池與鉛蓄電池相比，重量能量密度及體積能量密度較小。因此，於代替鉛蓄電池而將具有複數個鋰離子電池161之電池組16搭載於跨坐型車輛之情形時，可維持電瓶之容量，且使跨坐型車輛輕量化及小型化。或者，可不使跨坐型車輛大型化及重量化，而增大電瓶之容量。藉由使電池組之容量額外增大，電池組所具有之複數個金屬盒型電池之各者之負擔減輕，故而可抑制金屬盒型電池之劣化。 複數個金屬盒型電池(鋰離子電池)161之各者具有1個正極、1個負極、及電解液或固體電解質。金屬盒型電池之負極包含負極活性物質，該負極活性物質包含複數個碳層16121a、16121b、16121c而非石墨層，且複數個碳層之平均層間距離為鋰原子之直徑以上。 由於複數個碳層之平均層間距離為鋰離子之直徑以上，故而即便於金屬盒型電池充電時鋰離子進入至負極之相鄰之碳層之間，相鄰之碳層之間亦幾乎未擴寬。又，即便於金屬盒型電池161放電時鋰離子自相鄰之碳層之間離開，相鄰之碳層之間之距離亦不太變化。即，即便於金屬盒型電池161之充電時及放電時鋰離子進出碳層之間，複數個碳層之平均層間距離亦幾乎未變化。因此，碳層之積層狀態幾乎未變化。藉此，負極之結晶結構不太變化。因此，可抑制負極之劣化。因此，具有該負極之金屬盒型電池161可抑制劣化。因此，可抑制具有該負極之金屬盒型電池161之劣化。又，由於負極具有上述構成，故而即便金屬盒型電池161之充電及放電之頻度變高，亦可抑制金屬盒型電池161之劣化。進而，由於負極具有上述構成，故而具有該負極之金屬盒型電池161係即便於低溫之狀態下亦可抑制劣化。因此，即便將該金屬盒型電池161搭載於跨坐型車輛，且於低溫之狀態下金屬盒型電池161之充電及放電之頻度變高，亦可抑制金屬盒型電池(鋰離子電池)161之劣化。 又，由於金屬盒型電池161之正極包含具有橄欖石結構之正極活性物質，故而即便反覆進行充電與放電，金屬盒型電池(鋰離子電池)亦不易劣化。因此，即便於低溫環境下反覆進行金屬盒型電池之充電與放電，金屬盒型電池(鋰離子電池)161亦不易劣化。因此，即便將具有複數個金屬盒型電池161之電池組16搭載於跨坐型車輛，並相對較為頻繁地反覆進行電池組16之充電與放電，亦可抑制金屬盒型電池(鋰離子電池)161之劣化。即，即便為搭載於跨坐型車輛之電池組16之使用環境，亦可抑制金屬盒型電池(鋰離子電池)161之劣化。 進而，正極活性物質所具有之橄欖石結構係六方最密充電結構且係穩定之結晶結構。因此，上述構成之金屬盒型電池(鋰離子電池)於高溫環境下亦可使用。 又，正極活性物質具有橄欖石結構，且進而，負極活性物質包含經積層之複數個碳層16121a、16121b、16121c，且複數個碳層之平均層間距離為鋰原子之直徑以上。因此，於低溫之狀態下亦可抑制劣化。因此，可知即便將該金屬盒型電池161搭載於跨坐型車輛，且於低溫之狀態下金屬盒型電池161之充電及放電之頻度變高，亦可抑制金屬盒型電池(鋰離子電池)161之劣化。 又，當金屬盒型電池(鋰離子電池)161之輸出電流變大時，金屬盒型電池(鋰離子電池)161之SOC之變動幅度變大。 為了於SOC之變動幅度較大之使用狀況下使用電池組，並且還能提高電池組之耐久性或使電池組之放電時間變長，必須使電池組之容量變大。作為使電池組之容量變大之方法之一，考慮使電池組所具有之金屬盒型電池(鋰離子電池)之數量增加。 但，藉由金屬盒型電池(鋰離子電池)161具有上述構成之正極與負極，即便為金屬盒型電池(鋰離子電池)161之SOC之變動幅度較大之使用狀況，亦可抑制金屬盒型電池(鋰離子電池)161之劣化。因此，可抑制電池組16所具有之金屬盒型電池(鋰離子電池)161之數量之增加，且即便於SOC之變動幅度較大之使用狀況下使用電池組16，亦可使電池組16之耐久性提高或使電池組16之放電時間變長。此種電池組16可抑制重量及體積。因此，電池組16之操作變得更容易。因此，電池組16容易搭載於跨坐型車輛。又，電池組16之通用性提高。 進而，如上所述，金屬盒型電池(鋰離子電池)161係即便充電及放電之頻度變高亦不易劣化。因此，可抑制電池組16中所包含之金屬盒型電池(鋰離子電池)161之數量之增加。藉此，可抑制電池組16之重量及體積。因此，電池組16之操作變得更容易。因此，電池組16容易搭載於跨坐型車輛。又，電池組16之通用性提高。 又，複數個金屬盒型電池161之各者係具有金屬製之盒之金屬盒型電池，該金屬製之盒收容1個正極、1個負極、及電解液或固體電解質。金屬製之盒之散熱性較高。因此，即便於複數個金屬盒型電池161之充電時及放電時複數個金屬盒型電池161發熱，複數個金屬盒型電池161之各者亦進行散熱。藉此，可抑制具有複數個金屬盒型電池161之電池組16之溫度上升。因此，即便於將具有複數個金屬盒型電池之電池組16搭載於跨坐型車輛，且電池組16以大電流進行放電之情形時，亦可抑制電池組16之溫度上升。其結果，可抑制金屬盒型電池(鋰離子電池)161之劣化。即，即便為搭載於跨坐型車輛之電池組16之使用環境，亦可抑制由充電時或放電時之發熱所致之金屬盒型電池(鋰離子電池)161之劣化。 進而，複數個金屬盒型電池161係藉由金屬盒型電池固定部163而相互固定。因此，能夠以考慮到金屬盒型電池161之散熱性之佈局，維持複數個金屬盒型電池161之位置。例如，能夠以於金屬盒型電池161彼此之間空出適當之間隙之狀態予以維持。藉此，即便於複數個金屬盒型電池161之充電時及放電時複數個金屬盒型電池161發熱，亦可抑制電池組16之溫度上升。因此，即便於將具有複數個金屬盒型電池161之電池組16搭載於跨坐型車輛，且電池組16以大電流進行放電之情形時，亦可進一步抑制電池組16之溫度上升。其結果，可進一步抑制金屬盒型電池(鋰離子電池)161之劣化。即，即便為搭載於跨坐型車輛之電池組16之使用環境，亦可進一步抑制由充電時或放電時之發熱所致之金屬盒型電池(鋰離子電池)161之劣化。 又，藉由於金屬製之盒收容電解液，即便電解液揮發，金屬製之盒亦不會膨脹。因此，作為電解液，可使用揮發性較高之電解液。揮發性較高之電解液於低溫下不易凝固或凍結。因此，當使用低溫下不易凝固或凍結之電解液時，可於低溫環境下使用具有複數個金屬盒型電池161之電池組16。因此，即便將具有複數個金屬盒型電池161之電池組16搭載於跨坐型車輛，且在較搭載於汽車之電瓶更低溫之狀態下進行電池組16之充電或大電流之放電，亦可抑制金屬盒型電池161之劣化。即，即便為搭載於跨坐型車輛之電池組16之使用環境，亦可抑制由低溫環境下之充電或放電所致之金屬盒型電池(鋰離子電池)161之劣化。 ＜本發明之實施形態之具體例＞ 其次，一面參照圖2～圖6，一面對本發明之實施形態之具體例之電池組16進行說明。基本而言，本發明之實施形態之具體例具有上述本發明之實施形態之所有特徵。對與上述實施形態相同或相當之要素標附相同符號，關於該要素之說明不予重複。 如圖2所示，電池組16係搭載於跨坐型車輛1。電池組16可裝卸於跨坐型車輛1。電池組16亦可代替鉛蓄電池而搭載於可搭載鉛蓄電池之跨坐型車輛1。跨坐型車輛1係例如機車。跨坐型車輛1具備至少1個前輪2、及至少1個後輪3。又，跨坐型車輛1具備供騎乘者乘坐之座部。座部之至少一部分係於車輛前後方向上配置於較所有前輪2更靠後方。又，跨坐型車輛1具備作為車輛之驅動源之引擎10、及啟動馬達11。引擎之至少一部分亦可於車輛前後方向上配置於較所有前輪2更靠後方。啟動馬達係於引擎起動時，使引擎之曲軸旋轉。再者，以引擎作為驅動源之跨坐型車輛1亦可代替具有啟動馬達，而具有帶馬達功能之發電機(ISG：Integrated Starter Generator，一體式啟動發電機)。啟動馬達及ISG不適於本發明中之驅動源。 電池組16係對跨坐型車輛1之電力組件(電力消耗裝置)供給電力。電力組件包含啟動馬達。電力組件例如亦可包含控制裝置、儀錶、喇叭、燈、各種感測器及座部加熱器等。 電池組16具備複數個金屬盒型電池161、殼體部162、金屬盒型電池固定部163、1個外部正極端子166及1個外部負極端子167。電池組16所具備之金屬盒型電池161之數量並無特別限定。 複數個金屬盒型電池161之各者係鋰離子電池。複數個金屬盒型電池161係相互電性連接。電池組16所具有之金屬盒型電池16之數量並無特別限定。複數個金屬盒型電池161之各者係與複數個金屬盒型電池161中之任一者串聯連接。相互串聯連接之金屬盒型電池161之數量並無特別限定。於圖2中，使至少4個金屬盒型電池16串聯連接。複數個金屬盒型電池161亦可包含並聯連接之複數個金屬盒型電池161。相互並聯連接之金屬盒型電池161之數量並無特別限定。 金屬盒型電池固定部163係將複數個金屬盒型電池161相互固定。藉此，使複數個金屬盒型電池161一體化。例如，亦可藉由金屬盒型電池固定部163而將相鄰之金屬盒型電池161彼此固定。又，例如，亦可將不相鄰之金屬盒型電池161彼此固定。金屬盒型電池固定部163將複數個金屬盒型電池161相互固定之態樣並不限定於該態樣。 於複數個金屬盒型電池161固定於金屬盒型電池固定部163之狀態下，於相鄰之金屬盒型電池161之間可形成有空間，亦可未形成有空間。 外部正極端子166與外部負極端子167係分別以可自殼體部162之外部連接之狀態設置於殼體部162。外部正極端子166係與複數個金屬盒型電池161中之至少1個金屬盒型電池161所具有之至少1個正極電性連接。外部負極端子167係與複數個金屬盒型電池161中之至少1個金屬盒型電池161所具有之至少1個負極電性連接。 外部正極端子166及外部負極端子167亦可以如下方式連接。 外部正極端子166與外部負極端子167係連接於跨坐型車輛1之電力組件(啟動馬達11等)。又，外部正極端子166與外部負極端子167亦可亦連接於跨坐型車輛1之電源電路。於此情形時，電力組件與電源電路係並聯連接。跨坐型車輛1之電源電路例如亦可為12 V～15 V用之電源電路。電源電路例如亦可包含AC(Alternating Current，交流)發電機、及調節整流器。 於將電池組16進行充電時，外部正極端子166及外部負極端子167係連接於對電池組16供給電力之直流充電器。直流充電器係例如12 V～15 V用之直流充電器。電池組16可在搭載於跨坐型車輛1之狀態下被充電，亦可於自跨坐型車輛1卸除之狀態下被充電。 電池組16亦可具備管理複數個金屬盒型電池161之電池管理裝置(BMS：Battery Management System)。電池管理裝置係監視複數個金屬盒型電池161之充電與放電，且監視複數個金屬盒型電池161之充電與放電。 圖3係表示複數個金屬盒型電池161之連接態樣之一例。複數個金屬盒型電池161構成複數個包含相互並聯連接之複數個金屬盒型電池161之並聯電池群171。複數個並聯電池群171係相互串聯連接。 複數個金屬盒型電池161係相互相同之構成。圖4係表示金屬盒型電池161之一例之內部結構之立體圖。如圖4所示，金屬盒型電池161具有1個正極1611、1個負極1612及金屬製之盒1613。於以下之說明中，將金屬製之盒1613稱為金屬盒1613。正極1611及負極1612係收容於金屬盒1613。金屬盒1613具有密閉性。金屬盒1613之材質只要為金屬，則並無特別限定。作為金屬盒1613，例如亦可使用被實施鍍鎳之鋼鐵板。於圖4所示之例中，金屬盒1613為圓筒形狀。於圖4所示之例中，正極1611及負極1612係以繞特定之軸線捲繞之狀態收容於金屬盒1613。於圖4所示之例中，特定之軸線係金屬盒1613之中心軸線。於正極1611與負極1612之間，配置有隔離膜1614。隔離膜1614係與正極1611及負極1612一併繞特定之軸線捲繞。於金屬盒1613內，正極1611、負極1612及隔離膜1614係浸漬於電解液1615(參照圖5)。如此，金屬盒1613收容正極1611、負極1612、電解液1615及隔離膜1614。 一面參照圖5，一面進一步對金屬盒型電池161之結構進行說明。圖5係金屬盒型電池161之模型圖。 正極1611包含正極活性物質16111及集電體16112。正極活性物質16111具有橄欖石結構。正極活性物質例如為磷酸鐵鋰、磷酸錳鋰。 負極1612包含負極活性物質16121及集電體16122。負極活性物質16121具有複數個碳層16121a、16121b。負極活性物質16121亦可包含除碳以外之物質。負極活性物質例如亦可包含矽之氧化物。於複數個碳層16121a、16121b中亦可包含除碳以外之物質。負極活性物質16121例如亦可包含硬碳及軟碳中之至少一者。於負極活性物質16121中，相鄰之2層碳層(例如層16121a與層16121b)之間之平均距離為鋰原子之直徑以上。於圖5中，將鋰原子之直徑表示為D。又，將相鄰之2個碳層16121a、16121b之間之距離表示為L。相鄰之2個碳層16121a、16121b之間之距離有時亦被稱為相鄰之2個碳層16121a、16121b之層間距離。於圖5中，例示出相鄰之2層碳層16121a、16121b之層間距離L大於鋰原子之直徑D之情形。 負極活性物質16121之製造係使用碳源。碳源並無特別限定，若考慮產率，則較佳為包含大量碳之化合物。作為包含大量碳之化合物，例如可列舉石油瀝青、焦炭等來自石油之物質及椰子殼等來自植物之物質等。碳係根據起始原料而被分類為難石墨化碳(硬碳)、及易石墨化碳(軟碳)。碳源可使用難石墨化碳，亦可使用易石墨化碳，且亦可使用難石墨化碳及易石墨化碳之兩者。於惰性氛圍下，將碳於高溫下進行燒製，藉此，碳石墨化。石墨具有碳(carbon)之較薄之層經積層而得之結構。碳六元環二維地鍵結而成之較薄之層有時被稱為石墨烯。碳石墨化之溫度為2500℃以上且3000℃以下左右。燒製時之溫度越高且燒製時間越長，則於經積層之碳層中，相鄰之碳之間之距離(層間距離)越小，且碳層之大小、換言之微晶之大小越大。其結果，所謂結晶性增強。所謂石墨係指於將碳六元環二維地鍵結而成之層積層而得之結構中之層間距離結晶化為3.35埃以下而得者。 於將碳六元環二維地鍵結而成之層積層而得之結構中，平均層間距離未達鋰原子之直徑。因此，於具有複數個碳層之負極活性物質中，複數個碳層之平均層間距離為鋰原子之直徑以上之情形時，該負極活性物質係與石墨不同者。 隔離膜1614係多孔質膜。隔離膜1614例如由聚乙烯形成。 電解液1615係例如使鋰鹽溶解於有機溶劑所得之有機電解液。有機溶劑係例如碳酸乙二酯、碳酸丙二酯、碳酸二甲酯、碳酸二乙酯及碳酸甲酯乙酯。鋰鹽係例如六氟磷酸鋰、氟硼酸鋰及過氯酸鋰。電解液亦可為藉由對上述有機電解液添加聚合物而凝膠化所得者。聚合物係例如聚環氧乙烷、聚環氧丙烷及聚偏二氟乙烯。電解液1615亦可為於低溫下不易凝固或凍結之電解液。例如，電解液1615亦可為於-20℃不凍結之電解液。作為於-20℃不凍結之電解液，例如可列舉乙酸乙酯、乙酸甲酯及乙腈。 一面參照圖6，一面對電池組16之一例之更具體之結構進行說明。圖6係電池組16之一例之分解立體圖。再者，為了易於明確電池組16之內部結構，於圖6中表示出電池組16具備16個金屬盒型電池161之例。以下，使用圖6之紙面之上下方向，說明電池組16之結構。搭載於跨坐型車輛1之電池組16亦可以圖6之紙面之上下方向成為上下方向(鉛垂方向)之方式設置。搭載於跨坐型車輛1之電池組16之朝向並不限定於此。 殼體部162包含本體1621及蓋1622。本體1621與蓋1622可分離。蓋1622覆蓋形成於本體1621之開口。於蓋1622設置有1個外部正極端子166及1個外部負極端子167。 殼體部162為箱體。於圖6所示之例中，殼體部162為大致長方體狀之箱體。殼體部162具有上表面162a、下表面162b及4個側面162c、162d、162e、162f。由於殼體部162為大致長方體狀，故而殼體部162具有沿著相互交叉之3個平面分別配置之3個面。例如，上表面162a、側面162c及側面162f係沿著相互交叉之3個平面配置。 外部正極端子166與外部負極端子167均設置於上表面162a。即，外部正極端子166與外部負極端子167均設置於殼體部162之6個面中之1個面。換言之，外部正極端子166與外部負極端子167均設置於沿著相互交叉之3個平面分別配置之3個面中之1個面。外部正極端子166與外部負極端子167亦可設置於除上表面162a以外之面。外部正極端子166與外部負極端子167亦可設置於下表面162b及4個側面162c、162d、162e、162f中之任一個面。由於外部正極端子166與外部負極端子167設置於殼體部162之1個面，故而容易進行將外部正極端子166與外部負極端子167連接於跨坐型車輛1之電源電路等之作業、或連接於直流充電器之作業。 殼體部162收容16個金屬盒型電池161、金屬盒型電池固定部163、連接部164及平衡電路165。殼體部162亦可收容上述電池管理裝置。例如，電池管理裝置亦可安裝於蓋1622。再者，電池管理裝置亦可不收容於殼體部162。電池管理裝置亦可僅一部分收容於殼體部162。電池管理裝置亦可配置於殼體部162之外部。 金屬盒型電池固定部163具有2片金屬盒型電池固定板1631、1632。金屬盒型電池固定板1631係形成有16個孔1631a之板狀構件。金屬盒型電池固定板1632係形成有16個孔1632a之板狀構件。2個金屬盒型電池固定板1631、1632係配置於16個金屬盒型電池161之兩側。對於金屬盒型電池固定板1631之16個孔1631a，分別插入有16個金屬盒型電池161之一端部。對於金屬盒型電池固定板1632之16個孔1632a，分別插入有16個金屬盒型電池161之另一端部。藉此，金屬盒型電池固定部163係將16個金屬盒型電池161相互固定。於16個金屬盒型電池161固定於金屬盒型電池固定部163之狀態下，於相鄰之金屬盒型電池161之間形成有空間。金屬盒型電池固定部163未電性連接於複數個鋰離子電池161。 16個金屬盒型電池161係以排列成4行之狀態配置。即，各行係由4個金屬盒型電池161構成。構成第1行之4個金屬盒型電池161分別於其下端部具有正極端子。構成第1行之4個金屬盒型電池161分別於其上端部具有負極端子。構成第2行之4個金屬盒型電池161分別於其上端部具有正極端子。構成第2行之4個金屬盒型電池161分別於其下端部具有負極端子。構成第3行之4個金屬盒型電池161分別於其下端部具有正極端子。構成第3行之4個金屬盒型電池161分別於其上端部具有負極端子。構成第4行之4個金屬盒型電池161分別於其上端部具有正極端子。構成第4行之4個金屬盒型電池161分別於其下端部具有負極端子。 連接部164具有5片連接板1641、1642、1643、1644、1645。連接板1641、1642、1643、1644、1645係由具有導電性之物質形成。連接板1641係連接於構成第1行之4個金屬盒型電池161之負極端子。連接板1642係連接於構成第1行之4個金屬盒型電池161之正極端子。進而，連接板1642係連接於構成第2行之4個金屬盒型電池161之負極端子。連接板1643係連接於構成第2行之4個金屬盒型電池161之正極端子。進而，連接板1643連接構成第3行之4個金屬盒型電池161之負極端子。連接板1644係連接於構成第3行之4個金屬盒型電池161之正極端子。進而，連接板1644係連接於構成第4行之4個金屬盒型電池161之負極端子。連接板1645係連接於構成第4行之4個金屬盒型電池161之正極端子。 第1行之4個金屬盒型電池161係藉由連接板1641及連接板1642而相互並聯連接。藉此，第1行之4個金屬盒型電池161構成相互並聯連接之並聯電池群1711。第2行之4個金屬盒型電池161係藉由連接板1642及連接板1643而相互並聯連接。藉此，第2行之4個金屬盒型電池161構成相互並聯連接之並聯電池群1712。第3行之4個金屬盒型電池161係藉由連接板1643及連接板1644而相互並聯連接。藉此，第3行之4個金屬盒型電池161構成相互並聯連接之並聯電池群1713。第4行之4個金屬盒型電池161係藉由連接板1644及連接板1645而相互並聯連接。藉此，第4行之4個金屬盒型電池161構成相互並聯連接之並聯電池群1714。 又，第1行之4個金屬盒型電池161與第2行之4個金屬盒型電池161係藉由連接板1642而串聯連接。換言之，並聯電池群1711與並聯電池群1712係藉由連接板1642而串聯連接。第2行之4個金屬盒型電池161與第3行之4個金屬盒型電池161係藉由連接板1643而串聯連接。換言之，並聯電池群1712與並聯電池群1713係藉由連接板1643而串聯連接。第3行之4個金屬盒型電池161與第4行之4個金屬盒型電池161係藉由連接板1644而串聯連接。換言之，並聯電池群1713與並聯電池群1714係藉由連接板1644而串聯連接。藉此，4個並聯電池群1711、1712、1713、1714相互串聯連接。金屬盒型電池固定部163係將4個並聯電池群1711、1712、1713、1714以串聯連接之狀態固定。 連接板1641係經由未圖示之纜線而連接於外部負極端子167。藉此，第1行之4個金屬盒型電池161之負極端子電性連接於外部負極端子167。連接板1645係經由未圖示之纜線而連接於外部正極端子166。藉此，第4行之4個金屬盒型電池161之正極端子電性連接於外部正極端子166。 平衡電路165抑制16個金屬盒型電池161之充電之進展程度不均。一般而言，當將串聯連接之複數個電池進行充電時，有複數個電池之電壓產生偏差之情形。因此，有複數個電池之充電之進展程度產生偏差之情形。平衡電路165係例如藉由針對每個金屬盒型電池161使該金屬盒型電池161之電流泄放至電阻而減少金屬盒型電池161之電壓之偏差。再者，電池組16亦可不具有平衡電路165。 本發明之實施形態之具體例除發揮上述本發明之實施形態之效果以外，亦發揮以下之效果。 藉由在金屬盒1613收容電解液1615，即便電解液1615揮發，金屬盒1613亦不會膨脹。因此，作為電解液1615，可使用揮發性較高之電解液。揮發性較高之電解液於低溫下不易凝固或凍結。因此，於使用低溫下不易凝固或凍結之電解液之情形時，可於低溫環境下使用具有複數個金屬盒型電池161之電池組16。因此，即便將具有複數個金屬盒型電池161之電池組16搭載於跨坐型車輛，且在較搭載於汽車之電瓶更低溫之狀態下進行電池組之充電或大電流之放電，亦可抑制金屬盒型電池之劣化。即，即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制由低溫環境下之充電或放電所致之金屬盒型電池(鋰離子電池)之劣化。 藉由使用於-20℃不凍結之電解液作為電解液，可於-20℃左右之低溫之環境下使用具有複數個金屬盒型電池161之電池組16。因此，即便將具有複數個金屬盒型電池161之電池組16搭載於跨坐型車輛1，且於-20℃左右之低溫狀態下進行充電或大電流之放電，亦可抑制金屬盒型電池161之劣化。由此，即便為搭載於跨坐型車輛1之電池組16之使用環境，亦可進一步抑制金屬盒型電池161之劣化。 於殼體部162收容有複數個金屬盒型電池161及金屬盒型電池固定部163之兩者。藉此，可保護複數個金屬盒型電池161免受水或濕氣等之影響。因此，可抑制金屬盒型電池161之劣化。由此，即便於將電池組16搭載於不具有引擎室或馬達室之跨坐型車輛1之情形時，亦可抑制金屬盒型電池161之劣化。即，即便為搭載於跨坐型車輛1之電池組之使用環境，亦可進一步抑制金屬盒型電池161之劣化。 又，容易使複數個金屬盒型電池161及金屬盒型電池固定部163一同移動。因此，電池組16之操作變得更容易。因此，電池組16容易搭載於跨坐型車輛1。又，電池組16之通用性提高。 複數個並聯電池群171係相互串聯連接。藉由增加並聯電池群171之數量，可使電池組16之輸出電壓變高。複數個並聯電池群171之各者包含相互並聯連接之至少2個金屬盒型電池161。即，電池組16所具有之複數個金屬盒型電池包含相互並聯連接之金屬盒型電池161。因此，與電池組16所具有之複數個金屬盒型電池161串聯連接成1行之情形相比，電池組16之輸出電流變大。若電池組16之輸出電流變大，則電池組16之容量亦變大。相互並聯連接之金屬盒型電池161之數量越多，則電池組16之輸出電流與容量越大。由於電池組16之容量較大，故而可降低電池組16之充電頻度。其結果，可抑制金屬盒型電池161之劣化。該電池組16可使用於電池組16所需之輸出電壓、輸出電流及容量相對較大之使用環境。 藉由金屬盒型電池固定部163而將複數個金屬盒型電池161相互固定。藉此，容易使複數個金屬盒型電池161一同移動。因此，電池組16之操作變得容易。又，於相鄰之金屬盒型電池161彼此之間形成有空間。藉此，可使於複數個金屬盒型電池161之充電時及放電時產生之熱移動至該空間。除此以外，由於金屬盒型電池161之金屬盒1613為金屬製，故而金屬盒型電池161之散熱性較高。藉此，於複數個金屬盒型電池161之充電時及放電時，可抑制複數個金屬盒型電池161之溫度上升。 ＜本發明之實施形態之變更例＞ 本發明並不限定於上述實施形態及該實施形態之具體例，可於申請專利範圍所記載之範圍內進行各種變更。以下，對本發明之實施形態之變更例進行說明。再者，對於具有與上述構成相同之構成者，使用相同之符號並適當省略其說明。上述實施形態之具體例及下述變更例可適當組合後實施。 ◆複數個金屬盒型電池之連接態樣之變更例 於上述實施形態之具體例中，複數個金屬盒型電池161之連接態樣係將複數個包含相互並聯連接之至少2個金屬盒型電池161之並聯電池群171串聯連接之態樣。但，本發明之複數個金屬盒型電池之連接態樣並不限定於該態樣。本發明之複數個金屬盒型電池之連接態樣係只要複數個金屬盒型電池之各者與複數個金屬盒型電池中之任一者串聯連接便可。於本發明之複數個金屬盒型電池構成複數個並聯電池群之情形時，並聯電池群之數量並無特別限定。 本發明之複數個金屬盒型電池之連接態樣亦可為複數個金屬盒型電池串聯連接成1行之態樣。於複數個金屬盒型電池串聯連接成1行之情形時，與將相同數量之複數個金屬盒型電池串聯及並聯連接之情形相比，電池組之輸出電壓變高。因此，可一面確保電池組所需之輸出電壓，一面減少電池組所具有之金屬盒型電池之數量。由此，可使電池組小型且輕量。該電池組可使用於電池組所需之輸出電流與容量相對較小且電池組所需之輸出電壓相對較大之使用環境。 本發明之複數個金屬盒型電池之連接態樣亦可為將複數個包含相互串聯連接之至少2個金屬盒型電池之串聯電池群並聯連接之態樣。將其一例示於圖7。圖7之符號172表示串聯電池群。於本發明之複數個金屬盒型電池構成複數個串聯電池群之情形時，串聯電池群之數量並無特別限定。藉由使構成串聯電池群之金屬盒型電池之數量增加，可使電池組之輸出電壓變高。複數個串聯電池群係相互並聯連接。即，電池組所具有之複數個金屬盒型電池包含相互並聯連接之金屬盒型電池。因此，與電池組所具有之複數個金屬盒型電池串聯連接成1行之情形相比，電池組之輸出電流變大。若電池組之輸出電流變大，則電池組之容量亦變大。相互並聯連接之金屬盒型電池之數量越多，則電池組之輸出電流與容量越大。由於電池組之容量較大，故而可降低電池組之充電頻度。其結果，可抑制金屬盒型電池(鋰離子電池)之劣化。該電池組可使用於電池組所需之輸出電壓、輸出電流及容量相對較大之使用環境。 本發明之複數個金屬盒型電池之連接態樣亦可為將複數個串聯並聯群串聯連接之態樣，該串聯並聯群係將複數個包含相互串聯連接之至少2個金屬盒型電池之串聯電池群並聯連接而獲得。 本發明之複數個金屬盒型電池之連接態樣亦可為將複數個並聯串聯群並聯連接之態樣，該並聯串聯群係將複數個包含相互並聯連接之至少2個金屬盒型電池之並聯電池群串聯連接而獲得。 本發明之複數個金屬盒型電池之連接態樣亦可為將複數個並聯並聯群串聯連接之態樣，該並聯並聯群係將複數個包含相互並聯連接之至少2個金屬盒型電池之並聯電池群並聯連接而獲得。 複數個金屬盒型電池亦可包含相對於電池組中所包含之其他金屬盒型電池僅串聯連接之金屬盒型電池。複數個金屬盒型電池亦可包含相對於電池組中所包含之其他金屬盒型電池僅並聯連接之金屬盒型電池。 於本發明之複數個金屬盒型電池之連接態樣中，相互串聯連接之金屬盒型電池之數量並無限定。於將本發明之複數個金屬盒型電池串聯連接之態樣中，相互並聯連接之金屬盒型電池之數量並無限定。 於本發明之複數個金屬盒型電池之連接態樣中，串聯連接之金屬盒型電池之數量可相互相同，亦可不同。例如，於複數個金屬盒型電池具有2個串聯電池群之情形時，構成第1串聯電池群之金屬盒型電池之數量可與構成第2串聯電池群之金屬盒型電池之數量相同，亦可不同。 於本發明之複數個金屬盒型電池之連接態樣中，並聯連接之金屬盒型電池之數量可相互相同，亦可不同。例如，於複數個金屬盒型電池具有2個並聯電池群之情形時，構成第1並聯電池群之金屬盒型電池之數量可與構成第2並聯電池群之金屬盒型電池之數量相同，亦可不同。 ◆與金屬盒型固定部相關之變更例 上述實施形態之具體例之金屬盒型電池固定部163具有2片金屬盒型電池固定板1631、1632。但，金屬盒型電池固定部之構成並不限定於該態樣。例如，金屬盒型電池固定部亦可包含1個板狀構件。金屬盒型電池固定部亦可僅由金屬盒型電池固定板1631、1632之一者構成。又，金屬盒型電池固定部亦可包含2個以上之板狀構件。金屬盒型電池固定部亦可並非為板狀構件。 於上述實施形態之具體例中，於金屬盒型電池固定板1631之16個孔1631a，分別插入有複數個金屬盒型電池161之一端部。於金屬盒型電池固定板1632之16個孔1632a，分別插入有複數個金屬盒型電池161之另一端部。藉此，將複數個金屬盒型電池161相互固定。但，藉由金屬盒型電池固定部將複數個金屬盒型電池相互固定之態樣並不限定於該態樣。又，例如，亦可藉由將複數個金屬盒型電池分別嵌入至形成於金屬盒型電池固定部之複數個槽(凹部)，而將複數個金屬盒型電池相互固定。 於上述實施形態之具體例中，於在相鄰之金屬盒型電池161彼此之間形成有空間之狀態下，金屬盒型電池161相互固定。但，於本發明中，藉由金屬盒型電池固定部將複數個金屬盒型電池相互固定之態樣並不限定於該態樣。亦可於在複數個金屬盒型電池中之至少2個金屬盒型電池彼此之間未形成有空間之狀態下，將複數個金屬盒型電池相互固定。 於上述實施形態之具體例中，金屬盒型電池固定部163亦可不電性連接於複數個金屬盒型電池。但，於本發明中，金屬盒型電池固定部亦可兼用作將複數個金屬盒型電池相互電性連接之連接部。藉此，可減少零件數。其結果，可使電池組輕量化及小型化。另一方面，於在連接部之外另行設置金屬盒型電池固定部之情形時，可於藉由金屬盒型電池固定部將複數個金屬盒型電池相互固定之後，將連接部電性連接於金屬盒型電池。因此，容易進行金屬盒型電池與連接部之連接作業。 ◆與殼體部相關之變更例 於上述實施形態之具體例之電池組16中，複數個金屬盒型電池161及金屬盒型電池固定部163被收容於殼體部162。但，於本發明中，電池組之態樣並不限定於該態樣。複數個金屬盒型電池及金屬盒型電池固定部亦可不收容於殼體部。亦可為複數個金屬盒型電池中之一部分金屬盒型電池被收容於殼體部，剩餘之金屬盒型電池未被收容於殼體部。亦可為金屬盒型電池固定部之一部分被收容於殼體部，金屬盒型電池固定部之其他部分未被收容於殼體部。複數個金屬盒型電池及金屬盒型電池固定部亦可被收容於複數個殼體部。例如，亦可為複數個金屬盒型電池中之一部分金屬盒型電池被收容於第1殼體部，剩餘之金屬盒型電池被收容於第2殼體部。 上述實施形態之具體例之殼體部162包含本體1621及蓋1622。本體1621與蓋1622可分離。但，本發明之殼體部之態樣並不限定於該態樣。亦可為殼體部之本體與蓋無法分離。殼體部亦可包含3個以上之配件。 於上述實施形態之具體例中，電池組16之殼體部162為大致長方體狀之箱體。但，於本發明中，電池組之殼體部亦可為除長方體狀以外之多面體之箱體。於此情形時，殼體部亦具有沿著相互交叉之複數個平面分別配置之複數個面。於箱體為除長方體狀以外之多面體之情形時，該面之數量為至少4個。 ◆複數個金屬盒型電池之構成之變更例 於本發明中，金屬製之盒1613之形狀為圓筒形狀。但，金屬製之盒之形狀並不限定於圓筒形狀。例如，金屬製之盒亦可為箱狀(長方體狀)。例如，亦可為於箱狀之金屬製之盒，將正極及負極以繞特定之軸線捲繞之狀態收容於箱狀之金屬製之盒。又，金屬製之盒亦可為平板狀。例如，亦可為於平板狀之金屬製之盒，將正極及負極以平坦之狀態收容。例如，亦可為於平板狀之金屬製之盒，將金屬盒型電池之正極與負極積層。例如，亦可為於平板狀之金屬製之盒，將金屬盒型電池之正極及負極以繞特定之軸線捲繞之狀態收容。 於上述實施形態之具體例中，複數個金屬盒型電池161之各者具有正極1611、負極1612及電解液1615。但，於本發明中，金屬盒型電池亦可為具有正極、負極及固體電解質之金屬盒型電池。於此情形時，固體電解質係與正極及負極之兩者接觸。本發明之金屬盒型電池亦可為將正極、負極及固體電解質收容於金屬製之盒而得之金屬盒型電池。 又，複數個鋰離子電池161亦可包含具有正極、負極及電解液之金屬製盒型電池、以及具有正極、負極及固體電解質之金屬製盒型電池。 於上述實施形態之具體例中，複數個金屬盒型電池161為相互相同之構成。但，於本發明中，複數個鋰離子電池亦可包含互不相同之構成之至少2個鋰離子電池。即，複數個鋰離子電池亦可包含2種以上之鋰離子電池。 於上述實施形態之具體例中，複數個金屬盒型電池161所具有之正極活性物質為相互相同之種類。但，於本發明中，複數個金屬盒型電池中之至少2個金屬盒型電池所具有之正極活性物質亦可互不相同。即，複數個金屬盒型電池所具有之正極活性物質亦可為2種以上。 於上述實施形態之具體例中，複數個金屬盒型電池161所具有之負極活性物質為相互相同之種類。但，於本發明中，複數個金屬盒型電池中之至少2個金屬盒型電池所具有之負極活性物質亦可互不相同。即，複數個金屬盒型電池所具有之負極活性物質亦可為2種以上。例如，於複數個金屬盒型電池中之至少2個金屬盒型電池之負極中，複數個碳層之平均層間距離亦可互不相同。 於上述實施形態之具體例中，複數個金屬盒型電池161所具有之電解液為相互相同之種類。但，於本發明中，複數個金屬盒型電池中之至少2個金屬盒型電池所具有之電解液亦可互不相同。即，複數個金屬盒型電池所具有之電解液亦可為2種以上。又，於複數個金屬盒型電池具有正極、負極及固體電解質之情形時，複數個金屬盒型電池所具有之固體電解質亦可為相互相同之種類。又，複數個金屬盒型電池中之至少2個金屬盒型電池所具有之固體電解質亦可互不相同。即，複數個金屬盒型電池所具有之固體電解質亦可為2種以上。 又，複數個鋰離子電池161亦可包含具有正極、負極及電解液之1個以上之金屬製盒型電池、以及具有正極、負極及固體電解質之1個以上之金屬製盒型電池。於此情形時，具有正極、負極及電解液之複數個金屬製盒型電池中之至少2個金屬盒型電池所具有之電解液可為相互相同之種類，亦可互不相同。又，具有正極、負極及固體電解質之複數個金屬製盒型電池中之至少2個金屬盒型電池所具有之固體電解質可為相互相同之種類，亦可互不相同。 ◆溫度調整裝置 於上述實施形態之具體例中，亦可於殼體部收容有溫度調整裝置。溫度調整裝置係將形成於相鄰之鋰離子電池彼此之間之空間之溫度進行調整。溫度調整裝置例如亦可為空冷用風扇。溫度調整裝置例如亦可為冷水或溫水。溫度調整裝置例如亦可為加熱器。 ◆供搭載電池組之裝置之變更例 上述實施形態之具體例之電池組16係搭載於具有引擎之跨坐型車輛1。但，本發明之電池組既可搭載於以馬達作為驅動源之跨坐型車輛，亦可搭載於以馬達及引擎作為驅動源之跨坐型車輛。本發明之電池組亦可搭載於除跨坐型車輛以外之電力消耗裝置。電池組中所蓄積之電力被用於電力消耗裝置之驅動。供搭載電池組之電力消耗裝置之種類並無特別限定。電力消耗裝置可為車輛，亦可並非車輛。車輛可為以引擎作為驅動源者，亦可為以馬達作為驅動源者，且亦可為以引擎及馬達作為驅動源者。於將本發明之電池組搭載於在驅動源中包含馬達之車輛之情形時，電池組係對馬達(驅動源)供給電力。車輛可為於陸地上行駛者，亦可為於水上行駛者，且亦可為於水中行駛者，且亦可為於空中行駛者。於陸地上行駛之車輛係例如四輪車(four-wheel vehicle)、二輪車(two-wheel vehicle)、三輪車(three-wheeler)及雪上摩托車等。於陸地上行駛之車輛亦可為具有多於4個之車輪者。四輪車係例如客車、ATV(All Terrain Vehicle：全地形型車輛)、ROV(Recreational Off-highway Vehicle，休閒越野車)、高爾夫球車及堆高機等。二輪車可為具有排列於前後方向之2個車輪者，亦可為具有排列於左右方向之2個車輪之車輛。作為前者之例，例如為機車(機器腳踏車)、速克達、附踏板之輕型機車、腳踏車等。三輪車可為前輪為2個之車輛，亦可為後輪為2個之車輛。於水上行駛之車輛係例如船、水上摩托等。於水中行駛之車輛係例如潛水艇等。於空中行駛之車輛係例如飛機、直升機、遙控飛機等。 本發明之電池組既可為能夠相對於電力消耗裝置進行裝卸，亦可為無法進行裝卸。電池組既可於自電力消耗裝置卸除之狀態下被充電，亦可保持搭載於電力消耗裝置之狀態而被充電。 ◆與電池組之充電相關之變更例 本發明之電池組亦可為能夠利用除12 V～15 V用之直流充電器以外之充電器進行充電。於電池組利用較12 V～15 V更高電壓之直流充電器進行充電之情形時，可代替搭載於以馬達作為驅動源之車輛之鉛蓄電池而使用電池組。[實施例] 以下，一面參照圖8～圖11，一面對本發明之電池組所具有之金屬盒型電池之一例(以下有時稱為本發明例之鋰離子電池)之特性進行說明。本發明例之鋰離子電池係直徑為18 mm且長度為65.0 mm之圓筒型鋰離子電池、即所謂之18650電池。 (1)不同之電流值時之放電特性 利用定電流定電壓方式將本發明例之鋰離子電池進行充電。定電流充電中之充電電流係設為1 A。定電壓充電下之充電電壓係設為4.2 V。充電終止電流係設為0.05 A。充電結束後，使本發明例之鋰離子電池進行定電流放電。對將定電流放電中之放電電流設為1 A、3 A、5 A及10 A時之各放電容量進行研究。放電終止電壓係設為2.5 V。放電電流亦被稱為輸出電流。 圖8中表示放電電流為1 A、3 A、5 A及10 A時之鋰離子電池之各放電特性。圖8之縱軸係表示鋰離子電池之電壓，圖8之橫軸係表示鋰離子電池之放電容量。根據圖8，於放電電流為1 A、3 A、5 A及10 A中之任一者時，放電容量亦超過1 Ah。據此，可知本發明例之鋰離子電池即便於較高之放電率下，亦可加以利用。 (2)不同溫度環境下之循環特性 對下述3個溫度環境下之鋰離子電池之循環特性進行研究。於60℃之溫度環境下，反覆進行本發明例之鋰離子電池之充電及放電。於-10℃之溫度環境下，反覆進行本發明例之鋰離子電池之充電及放電。於假定ASEAN(Association of Southeast Asian Nations，東南亞國家協會)之四季之溫度環境下，反覆進行本發明例之鋰離子電池之充電及放電。具體而言，假定1年之溫度依照40℃、25℃、10℃、25℃之順序改變。將充電與放電計數為1次循環，每2500次循環使環境溫度依照40℃、25℃、10℃、25℃之順序反覆變化。 首先，為了使鋰離子電池為滿充電狀態，而利用定電流定電壓方式將鋰離子電池進行充電。定電流充電下之充電電流係設為1 A。定電壓充電下之充電電壓係設為3.65 V。充電終止電流係設為0.05 A。其後，反覆進行充電及放電。每當2500次循環結束時，將鋰離子電池設為滿充電狀態。於使鋰離子電池為滿充電狀態時，利用定電流定電壓方式將鋰離子電池進行充電。定電流充電下之充電電流係設為1 A。定電壓充電下之充電電壓係設為3.65 V。充電終止電流係設為0.05 A。 圖9中表示出充放電循環中之1次循環之負載電流之圖案。圖9之縱軸係負載電流，圖9之橫軸係時間。於圖9中，當負載電流為負時，將鋰離子電池進行放電。於圖9中，當負載電流為正時，將鋰離子電池進行充電。圖9所示之負載電流之圖案係基於ECE(Economic Commission for Europe，歐洲經濟委員會)40(ISO(International Organization for Standardization，國際標準組織)6460)中所規定之行駛條件而生成。ECE40(ISO6460)中所規定之行駛條件有時亦稱為ECE40行駛圖案。所謂ECE40行駛圖案係歐洲實際燃料效率測定法即ECE40城市循環模式下之行駛圖案。 針對每2500次循環，測定鋰離子電池之電池容量。具體而言，利用以下方法進行。首先，於25℃之溫度環境下，利用定電流定電壓方式進行充電。定電流充電下之充電電流係設為1 A。定電壓充電下之充電電壓係設為3.65 V。充電終止電流係設為0.05 A。充電結束後，於25℃之溫度環境下進行定電流放電，測定鋰離子電池之放電容量。定電流放電中之放電電流係設為1 A。放電終止電壓係設為2.5 V。 藉由將每2500次循環之鋰離子電池之放電容量除以第1次循環之放電時之放電容量，而求出相對於第1次循環之放電時之放電容量而言的第特定次循環之放電時之放電容量。此處，將相對於第1次循環之放電時之放電容量而言的第特定次循環之放電時之放電容量稱為初始容量比。該初始容量比有時亦稱為容量維持率。 圖10中表示初始容量比與循環數之關係。圖10之縱軸係初始容量比，圖10之橫軸係循環數。根據圖10，可知以下內容。於-10℃之低溫環境及假定ASEAN之四季之溫度環境下，第20000次循環之初始容量比為95%。又，-10℃之低溫環境之初始容量比、及假定ASEAN之四季之溫度環境之初始容量比表現出相似之傾向。據此，可知本發明例之鋰離子電池係即便於-10℃之低溫環境下反覆進行充電及放電，亦具有與假定ASEAN之四季之溫度環境相同之耐久性。又，於60℃之高溫環境下，第20000次循環之初始容量比亦為80%。據此，可謂即便於高溫環境下，本發明例之鋰離子電池之耐久性亦較高。根據上述，本發明例之鋰離子電池無論於低溫環境下亦或於高溫環境下，耐久性均較高。即，本發明例之鋰離子電池無論於低溫環境下亦或於高溫環境下，均不易劣化。因此，本發明例之鋰離子電池之使用環境之自由度較高。 (3)本發明例與比較例之循環特性之比較 作為比較例，使用正極活性物質為磷酸鐵鋰且負極活性物質為石墨之鋰離子電池。 於45℃之環境下，反覆進行本發明例之鋰離子電池與比較例之鋰離子電池之充電及放電。具體而言，反覆進行如下操作：於進行定電流定電壓充電之後，進行定電流放電。自充電結束至放電開始為止之待機時間係設為30分鐘。自放電結束至充電開始為止之待機時間係設為30分鐘。定電流充電下之充電電流係設為3 A。定電壓充電下之充電電壓係設為3.6 V。充電終止電流係設為0.05 A。定電流放電之放電電流係設為3 A。放電終止電壓係設為2.5 V。 於特定之循環之充電及放電結束後，藉由以下之方法而測定鋰離子電池之放電容量。 首先，於25℃之環境下，利用定電流定電壓方式進行充電。定電流充電下之充電電流係設為1 A。定電壓充電下之充電電壓係設為3.65 V。充電終止電流係設為0.05 A。其後，於25℃之環境下進行定電流放電，測定鋰離子電池之放電容量。放電電流係設為1 A。放電終止電壓係設為2.5 V。 測定第1次循環之放電時之放電容量、及特定之循環結束後之放電時之放電容量。藉由將特定之循環結束後之放電時之放電容量除以第1次循環之放電時之放電容量，而求出相對於第1次循環之放電時之放電容量而言的特定之循環結束後之放電時之放電容量。此處，將相對於第1次循環之放電時之放電容量而言的特定之循環結束後之放電時之放電容量稱為初始容量比。 於圖11中表示初始容量比與循環數之關係。圖11之縱軸係初始容量比，圖11之橫軸係循環數。根據圖11，於各循環中，本發明例之鋰離子電池之初始容量比大於比較例之鋰離子電池之初始容量比。又，本發明例之鋰離子電池之初始容量比於100次循環中約為99%。另一方面，比較例之鋰離子電池之初始容量比於100次循環中，低於約96%。 可知本發明例之鋰離子電池與比較例之鋰離子電池相比可更抑制劣化。 根據上述，本發明例之鋰離子電池係即便於低溫環境下及高溫環境下反覆進行充電及放電，亦可抑制劣化。又，本發明例之鋰離子電池係即便長時間反覆進行充電及放電，亦可抑制劣化。因此，具有本發明例之複數個鋰離子電池之電池組係即便為搭載於跨坐型車輛之電池組之使用環境，亦可抑制鋰離子電池之劣化。 再者，作為本案之基礎申請之日本專利特願2017-038284之電池組包含於本案說明書之電池組中。該基礎申請中之鋰離子電池161相當於本案說明書之金屬盒型電池161或鋰離子電池161。該基礎申請中之罐1613相當於本案說明書之金屬製之盒1613或金屬盒1613。該基礎申請中之盒部162相當於本案說明書之殼體部162。該基礎申請中之罐電池固定部163相當於本案說明書之金屬盒型電池固定部163。<Embodiment of the Invention> Hereinafter, a battery pack 16 according to an embodiment of the present invention will be described with reference to Fig. 1 . The battery pack 16 has a plurality of metal case type batteries 161 connected to each other. Each of the plurality of metal case type batteries 161 is connected in series to any one of a plurality of metal case type batteries 161. Each of the plurality of metal case type batteries 161 may be connected in series to any one of the plurality of metal case type batteries 161. Each of the plurality of metal case type batteries 161 may be connected in series to two or more of the metal case type batteries 161 of the plurality of metal case type batteries 161. Each of the plurality of metal box type batteries 161 is a metal box type battery having the following: one positive electrode; one negative electrode; an electrolyte or a solid electrolyte; and a metal case that houses one positive electrode and one negative electrode. And electrolyte. The positive electrode has a positive active material of an olivine structure. The negative electrode has a negative electrode active material containing a plurality of carbon layers 16121a, 16121b, and 16121c, and an average interlayer distance of the plurality of carbon layers is equal to or larger than a diameter of the lithium atom. FIG. 1 illustrates a case where lithium atoms are present between two adjacent carbon layers 16121a and 16121b. Further, a case where a lithium atom exists between two adjacent carbon layers 16121b and 16121c is exemplified. In Fig. 1, the diameter of the lithium atom is represented as D. Further, the distance between the adjacent two carbon layers 16121a and 16121b is represented as L. The distance between the adjacent two carbon layers 16121a and 16121b is sometimes referred to as the interlayer distance between the adjacent two carbon layers 16121a and 16121b. In FIG. 1, the case where the distance L between the adjacent two carbon layers 16121a and 16121b is larger than the diameter D of the lithium atom is exemplified. The battery pack 16 has a metal case type battery fixing portion that fixes a plurality of metal case types by fixing each of the plurality of metal case type batteries 161 to the metal case type battery 161 connected in series. The batteries 161 are fixed to each other. According to this configuration, each of the plurality of metal battery cells 161 is connected in series to any of the plurality of metal battery cells 161. The greater the number of metal box type batteries 161 connected in series to each other, the higher the output voltage of the battery pack 16. By increasing the number of metal cassette type batteries 161 connected in series to each other, the battery pack 16 can be used in an environment where a higher output voltage is required. The metal box type battery 161 is a lithium ion battery. Lithium-ion batteries have lower weight energy density and volumetric energy density than lead batteries. Therefore, when the battery pack 16 having a plurality of lithium ion batteries 161 is mounted on a straddle type vehicle instead of the lead storage battery, the capacity of the battery can be maintained, and the straddle type vehicle can be made lighter and smaller. Alternatively, the capacity of the battery can be increased without increasing the size and weight of the straddle type vehicle. By additionally increasing the capacity of the battery pack, the burden on each of the plurality of metal-cassette batteries of the battery pack is reduced, so that deterioration of the metal-cassette battery can be suppressed. Each of a plurality of metal case type batteries (lithium ion batteries) 161 has one positive electrode, one negative electrode, and an electrolytic solution or a solid electrolyte. The negative electrode of the metal cassette type battery includes a negative electrode active material containing a plurality of carbon layers 16121a, 16121b, and 16121c instead of a graphite layer, and an average interlayer distance of the plurality of carbon layers is equal to or larger than a diameter of the lithium atom. Since the average interlayer distance of the plurality of carbon layers is greater than the diameter of the lithium ions, even if the lithium ions enter between the adjacent carbon layers of the negative electrode during charging of the metal box type battery, the adjacent carbon layers are hardly expanded. width. Further, even when lithium metal ions are separated from the adjacent carbon layers when the metal battery cell 161 is discharged, the distance between adjacent carbon layers does not change much. That is, even when lithium metal ions enter and exit the carbon layer during charging of the metal case type battery 161 and during discharge, the average interlayer distance of the plurality of carbon layers hardly changes. Therefore, the laminated state of the carbon layer hardly changes. Thereby, the crystal structure of the negative electrode does not change much. Therefore, deterioration of the negative electrode can be suppressed. Therefore, the metal box type battery 161 having the negative electrode can suppress deterioration. Therefore, deterioration of the metal cassette type battery 161 having the negative electrode can be suppressed. Further, since the negative electrode has the above configuration, even if the frequency of charging and discharging of the metal battery cell 161 is increased, deterioration of the metal battery cell 161 can be suppressed. Further, since the negative electrode has the above-described configuration, the metal case type battery 161 having the negative electrode can suppress deterioration even in a low temperature state. Therefore, even if the metal cassette type battery 161 is mounted on the straddle type vehicle and the frequency of charging and discharging of the metal case type battery 161 is high in a low temperature state, the metal case type battery (lithium ion battery) 161 can be suppressed. Deterioration. Further, since the positive electrode of the metal case type battery 161 includes the positive electrode active material having an olivine structure, the metal cassette type battery (lithium ion battery) is not easily deteriorated even if charging and discharging are repeated. Therefore, even if the charging and discharging of the metal cassette type battery are repeated in a low temperature environment, the metal cassette type battery (lithium ion battery) 161 is not easily deteriorated. Therefore, even if the battery pack 16 having a plurality of metal-cassette batteries 161 is mounted on the straddle-type vehicle and the charging and discharging of the battery pack 16 are repeated relatively frequently, the metal-cassette battery (lithium-ion battery) can be suppressed. Deterioration of 161. In other words, even in the use environment of the battery pack 16 mounted on the straddle type vehicle, deterioration of the metal cassette type battery (lithium ion battery) 161 can be suppressed. Further, the olivine structure of the positive electrode active material is a hexagonal most densely charged structure and is a stable crystal structure. Therefore, the metal box type battery (lithium ion battery) having the above configuration can also be used in a high temperature environment. Further, the positive electrode active material has an olivine structure, and further, the negative electrode active material includes a plurality of laminated carbon layers 16121a, 16121b, and 16121c, and the average interlayer distance of the plurality of carbon layers is equal to or larger than the diameter of the lithium atoms. Therefore, deterioration can be suppressed even in a low temperature state. Therefore, it is understood that the metal cassette type battery 161 can be mounted on a straddle type vehicle, and the frequency of charging and discharging of the metal case type battery 161 is high in a low temperature state, and the metal case type battery (lithium ion battery) can be suppressed. Deterioration of 161. Moreover, when the output current of the metal-cassette type battery (lithium ion battery) 161 becomes large, the fluctuation range of the SOC of the metal-cassette type battery (lithium-ion battery) 161 becomes large. In order to use the battery pack in a use condition where the SOC varies greatly, and it is also possible to increase the durability of the battery pack or to increase the discharge time of the battery pack, it is necessary to increase the capacity of the battery pack. As one of methods for increasing the capacity of the battery pack, it is considered to increase the number of metal cartridge type batteries (lithium ion batteries) included in the battery pack. However, the metal case type battery (lithium ion battery) 161 has the positive electrode and the negative electrode of the above-described configuration, and the metal case can be suppressed even if the SOC of the metal case type battery (lithium ion battery) 161 has a large fluctuation range. Deterioration of the type battery (lithium ion battery) 161. Therefore, it is possible to suppress an increase in the number of metal-cassette type batteries (lithium-ion batteries) 161 of the battery pack 16, and to use the battery pack 16 even in a use condition in which the fluctuation range of the SOC is large, the battery pack 16 can be made. The durability is increased or the discharge time of the battery pack 16 is lengthened. Such a battery pack 16 can suppress weight and volume. Therefore, the operation of the battery pack 16 becomes easier. Therefore, the battery pack 16 is easily mounted on a straddle type vehicle. Moreover, the versatility of the battery pack 16 is improved. Further, as described above, the metal cassette type battery (lithium ion battery) 161 is less likely to deteriorate even when the frequency of charging and discharging becomes high. Therefore, an increase in the number of metal cassette type batteries (lithium ion batteries) 161 included in the battery pack 16 can be suppressed. Thereby, the weight and volume of the battery pack 16 can be suppressed. Therefore, the operation of the battery pack 16 becomes easier. Therefore, the battery pack 16 is easily mounted on a straddle type vehicle. Moreover, the versatility of the battery pack 16 is improved. Further, each of the plurality of metal case type batteries 161 is a metal case type battery having a metal case, and the metal case houses one positive electrode, one negative electrode, and an electrolytic solution or a solid electrolyte. The metal case has a high heat dissipation. Therefore, even when a plurality of metal case type batteries 161 are charged during charging and discharging, a plurality of metal case type batteries 161 are heated, and each of the plurality of metal case type batteries 161 is also radiated. Thereby, the temperature rise of the battery pack 16 having the plurality of metal cassette type batteries 161 can be suppressed. Therefore, even when the battery pack 16 having a plurality of metal-cassette batteries is mounted on the straddle-type vehicle and the battery pack 16 is discharged with a large current, the temperature rise of the battery pack 16 can be suppressed. As a result, deterioration of the metal cassette type battery (lithium ion battery) 161 can be suppressed. In other words, even in the use environment of the battery pack 16 mounted on the straddle-type vehicle, deterioration of the metal-cassette battery (lithium ion battery) 161 due to heat generation during charging or discharging can be suppressed. Further, a plurality of metal box type batteries 161 are fixed to each other by the metal box type battery fixing portion 163. Therefore, the position of the plurality of metal case type batteries 161 can be maintained in consideration of the layout of the heat dissipation of the metal case type battery 161. For example, it can be maintained in a state in which the metal cassette type batteries 161 are provided with a proper gap therebetween. Thereby, even when a plurality of metal case type batteries 161 are charged and a plurality of metal case type batteries 161 are heated during charging, the temperature rise of the battery pack 16 can be suppressed. Therefore, even when the battery pack 16 having the plurality of metal battery cells 161 is mounted on the straddle type vehicle and the battery pack 16 is discharged with a large current, the temperature rise of the battery pack 16 can be further suppressed. As a result, deterioration of the metal cassette type battery (lithium ion battery) 161 can be further suppressed. In other words, even in the use environment of the battery pack 16 mounted on the straddle-type vehicle, deterioration of the metal-cassette battery (lithium ion battery) 161 due to heat generation during charging or discharging can be further suppressed. Further, since the electrolytic solution is accommodated in the metal case, the metal case does not expand even if the electrolytic solution is volatilized. Therefore, as the electrolytic solution, an electrolyte having a high volatility can be used. The electrolyte with higher volatility is less likely to solidify or freeze at low temperatures. Therefore, when an electrolyte which is hard to solidify or freeze at a low temperature is used, the battery pack 16 having a plurality of metal cassette type batteries 161 can be used in a low temperature environment. Therefore, even if the battery pack 16 having the plurality of metal-cassette batteries 161 is mounted on the straddle-type vehicle, and the battery pack 16 is charged or discharged at a lower temperature than the battery mounted in the automobile, the battery pack 16 can be charged or discharged with a large current. The deterioration of the metal cassette type battery 161 is suppressed. In other words, even in the use environment of the battery pack 16 mounted on the straddle-type vehicle, deterioration of the metal-cassette battery (lithium ion battery) 161 caused by charging or discharging in a low-temperature environment can be suppressed. <Specific Example of Embodiment of the Present Invention> Next, a battery pack 16 according to a specific example of the embodiment of the present invention will be described with reference to Figs. 2 to 6 . Basically, specific examples of the embodiments of the present invention have all the features of the above-described embodiments of the present invention. The same or equivalent elements as those of the above-described embodiments are denoted by the same reference numerals, and the description of the elements will not be repeated. As shown in FIG. 2, the battery pack 16 is mounted on the straddle type vehicle 1. The battery pack 16 is detachable from the straddle type vehicle 1. The battery pack 16 can also be mounted on a straddle type vehicle 1 that can be equipped with a lead storage battery instead of a lead storage battery. The straddle type vehicle 1 is, for example, a locomotive. The straddle-type vehicle 1 includes at least one front wheel 2 and at least one rear wheel 3. Further, the straddle-type vehicle 1 is provided with a seat for the rider to ride. At least a portion of the seat portion is disposed further rearward than all of the front wheels 2 in the longitudinal direction of the vehicle. Further, the straddle-type vehicle 1 includes an engine 10 as a driving source of the vehicle and a starter motor 11. At least a portion of the engine may be disposed further rearward than all of the front wheels 2 in the longitudinal direction of the vehicle. The starter motor is used to rotate the crankshaft of the engine when the engine is started. Further, the straddle-type vehicle 1 using the engine as a driving source may have a generator-equipped generator (ISG: Integrated Starter Generator) instead of having a starter motor. The starter motor and ISG are not suitable for the drive source in the present invention. The battery pack 16 supplies electric power to a power component (power consuming device) of the straddle type vehicle 1 . The power component contains a starter motor. The power component can also include, for example, control devices, meters, speakers, lights, various sensors, and seat heaters. The battery pack 16 includes a plurality of metal case type batteries 161, a case portion 162, a metal case type battery fixing portion 163, one external positive electrode terminal 166, and one external negative electrode terminal 167. The number of the metal case type batteries 161 included in the battery pack 16 is not particularly limited. Each of the plurality of metal case type batteries 161 is a lithium ion battery. A plurality of metal box type batteries 161 are electrically connected to each other. The number of the metal case type batteries 16 included in the battery pack 16 is not particularly limited. Each of the plurality of metal case type batteries 161 is connected in series to any one of a plurality of metal case type batteries 161. The number of the metal box type batteries 161 connected in series to each other is not particularly limited. In Fig. 2, at least four metal cassette type batteries 16 are connected in series. The plurality of metal box type batteries 161 may also include a plurality of metal box type batteries 161 connected in parallel. The number of the metal box type batteries 161 connected in parallel with each other is not particularly limited. The metal box type battery fixing portion 163 fixes a plurality of metal box type batteries 161 to each other. Thereby, a plurality of metal cassette type batteries 161 are integrated. For example, the adjacent metal cassette type batteries 161 may be fixed to each other by the metal box type battery fixing portion 163. Further, for example, the metal battery cells 161 that are not adjacent to each other may be fixed to each other. The metal box type battery fixing portion 163 is not limited to this aspect in which a plurality of metal box type batteries 161 are fixed to each other. In a state in which a plurality of metal case type batteries 161 are fixed to the metal case type battery fixing portion 163, a space may be formed between the adjacent metal case type batteries 161, and a space may not be formed. The external positive electrode terminal 166 and the external negative electrode terminal 167 are respectively provided in the case portion 162 in a state of being connectable from the outside of the case portion 162. The external positive electrode terminal 166 is electrically connected to at least one positive electrode of at least one of the plurality of metal battery cells 161. The external negative electrode terminal 167 is electrically connected to at least one of the negative electrodes of at least one of the plurality of metal battery cells 161. The external positive terminal 166 and the external negative terminal 167 can also be connected as follows. The external positive terminal 166 and the external negative terminal 167 are connected to the power module (the starter motor 11 or the like) of the straddle type vehicle 1. Further, the external positive terminal 166 and the external negative terminal 167 may also be connected to the power supply circuit of the straddle type vehicle 1. In this case, the power component is connected in parallel with the power circuit. The power supply circuit of the straddle type vehicle 1 can be, for example, a power supply circuit for 12 V to 15 V. The power supply circuit may also include, for example, an AC (Alternating Current) generator and an adjustment rectifier. When the battery pack 16 is charged, the external positive terminal 166 and the external negative terminal 167 are connected to a DC charger that supplies power to the battery pack 16. The DC charger is, for example, a DC charger for 12 V to 15 V. The battery pack 16 can be charged while being mounted on the straddle-type vehicle 1 or can be charged in a state where the straddle-type vehicle 1 is removed. The battery pack 16 may also include a battery management device (BMS: Battery Management System) that manages a plurality of metal-cassette batteries 161. The battery management device monitors charging and discharging of a plurality of metal case type batteries 161, and monitors charging and discharging of a plurality of metal case type batteries 161. Fig. 3 is a view showing an example of a connection state of a plurality of metal case type batteries 161. The plurality of metal box type batteries 161 constitute a plurality of parallel battery groups 171 including a plurality of metal box type batteries 161 connected in parallel with each other. A plurality of parallel battery groups 171 are connected in series to each other. A plurality of metal box type batteries 161 are configured to be identical to each other. Fig. 4 is a perspective view showing the internal structure of an example of the metal case type battery 161. As shown in FIG. 4, the metal case type battery 161 has one positive electrode 1611, one negative electrode 1612, and a metal case 1613. In the following description, the metal case 1613 is referred to as a metal case 1613. The positive electrode 1611 and the negative electrode 1612 are housed in a metal case 1613. The metal case 1613 has airtightness. The material of the metal case 1613 is not particularly limited as long as it is metal. As the metal case 1613, for example, a steel plate to which nickel plating is applied may be used. In the example shown in FIG. 4, the metal case 1613 has a cylindrical shape. In the example shown in FIG. 4, the positive electrode 1611 and the negative electrode 1612 are housed in the metal case 1613 in a state of being wound around a specific axis. In the example shown in Figure 4, the particular axis is the central axis of the metal box 1613. A separator 1614 is disposed between the positive electrode 1611 and the negative electrode 1612. The separator 1614 is wound around a specific axis together with the positive electrode 1611 and the negative electrode 1612. In the metal case 1613, the positive electrode 1611, the negative electrode 1612, and the separator 1614 are immersed in the electrolytic solution 1615 (see FIG. 5). In this manner, the metal case 1613 houses the positive electrode 1611, the negative electrode 1612, the electrolytic solution 1615, and the separator 1614. The structure of the metal case type battery 161 will be further described with reference to Fig. 5 . Fig. 5 is a model diagram of a metal case type battery 161. The positive electrode 1611 includes a positive electrode active material 16111 and a current collector 16112. The positive electrode active material 16111 has an olivine structure. The positive electrode active material is, for example, lithium iron phosphate or lithium manganese phosphate. The negative electrode 1612 includes a negative electrode active material 16121 and a current collector 16122. The negative electrode active material 16121 has a plurality of carbon layers 16121a and 16121b. The negative electrode active material 16121 may also contain a substance other than carbon. The negative electrode active material may, for example, also contain an oxide of cerium. A substance other than carbon may be contained in the plurality of carbon layers 16121a and 16121b. The negative electrode active material 16121 may include, for example, at least one of hard carbon and soft carbon. In the negative electrode active material 16121, the average distance between two adjacent carbon layers (for example, the layers 16121a and 16121b) is equal to or larger than the diameter of the lithium atoms. In Fig. 5, the diameter of the lithium atom is represented as D. Further, the distance between the adjacent two carbon layers 16121a and 16121b is represented as L. The distance between the adjacent two carbon layers 16121a and 16121b is sometimes referred to as the interlayer distance between the adjacent two carbon layers 16121a and 16121b. In FIG. 5, the case where the interlayer distance L between the adjacent two carbon layers 16121a and 16121b is larger than the diameter D of the lithium atom is exemplified. The negative electrode active material 16121 is produced by using a carbon source. The carbon source is not particularly limited, and in view of the yield, a compound containing a large amount of carbon is preferred. Examples of the compound containing a large amount of carbon include petroleum-derived materials such as petroleum pitch and coke, and plant-derived substances such as coconut shell. The carbon system is classified into non-graphitizable carbon (hard carbon) and easily graphitizable carbon (soft carbon) depending on the starting materials. The carbon source may use non-graphitizable carbon, may also use easily graphitizable carbon, and may also use both non-graphitizable carbon and easily graphitizable carbon. The carbon is graphitized by firing the carbon at a high temperature in an inert atmosphere. Graphite has a structure in which a thin layer of carbon is laminated. The thinner layer in which the carbon six-membered ring is two-dimensionally bonded is sometimes referred to as graphene. The temperature at which carbon is graphitized is about 2500 ° C or more and about 3000 ° C or less. The higher the temperature during firing and the longer the firing time, the smaller the distance between the adjacent carbon layers (interlayer distance) in the carbon layer of the laminate, and the larger the size of the carbon layer, in other words, the size of the crystallites. Big. As a result, the crystallinity is enhanced. The term "graphite" refers to the crystallization of the interlayer distance in a structure obtained by two-dimensionally bonding a carbon six-membered ring to 3. Those who are below 35 angstroms. In the structure obtained by layering a carbon six-membered ring in two dimensions, the average interlayer distance is less than the diameter of the lithium atom. Therefore, in the case of the negative electrode active material having a plurality of carbon layers, when the average interlayer distance of the plurality of carbon layers is equal to or larger than the diameter of the lithium atom, the negative electrode active material is different from graphite. The separator 1614 is a porous film. The separator 1614 is formed, for example, of polyethylene. The electrolytic solution 1615 is, for example, an organic electrolytic solution obtained by dissolving a lithium salt in an organic solvent. The organic solvent is, for example, ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. The lithium salt is, for example, lithium hexafluorophosphate, lithium fluoroborate or lithium perchlorate. The electrolytic solution may be obtained by gelation of a polymer added to the above organic electrolytic solution. The polymers are, for example, polyethylene oxide, polypropylene oxide and polyvinylidene fluoride. The electrolyte 1615 may also be an electrolyte that is not easily solidified or frozen at a low temperature. For example, the electrolyte 1615 may also be an electrolyte that does not freeze at -20 °C. Examples of the electrolytic solution which does not freeze at -20 ° C include ethyl acetate, methyl acetate, and acetonitrile. Referring to Fig. 6, a more specific structure of an example of the battery pack 16 will be described. Fig. 6 is an exploded perspective view showing an example of the battery pack 16. Further, in order to make it easy to clarify the internal structure of the battery pack 16, an example in which the battery pack 16 is provided with 16 metal-cassette batteries 161 is shown in FIG. Hereinafter, the structure of the battery pack 16 will be described using the upper and lower directions of the paper surface of Fig. 6. The battery pack 16 mounted on the straddle-type vehicle 1 may be provided in a vertical direction (vertical direction) in the up-down direction of the paper surface of FIG. The orientation of the battery pack 16 mounted on the straddle type vehicle 1 is not limited to this. The housing portion 162 includes a body 1621 and a cover 1622. The body 1621 is separable from the cover 1622. The cover 1622 covers the opening formed in the body 1621. The outer cover 166 and one outer negative terminal 167 are provided in the cover 1622. The housing portion 162 is a case. In the example shown in FIG. 6, the casing portion 162 is a substantially rectangular parallelepiped casing. The housing portion 162 has an upper surface 162a, a lower surface 162b, and four side surfaces 162c, 162d, 162e, and 162f. Since the casing portion 162 has a substantially rectangular parallelepiped shape, the casing portion 162 has three faces arranged along three planes that intersect each other. For example, the upper surface 162a, the side surface 162c, and the side surface 162f are arranged along three planes that intersect each other. Both the external positive terminal 166 and the external negative terminal 167 are disposed on the upper surface 162a. That is, both the external positive electrode terminal 166 and the external negative electrode terminal 167 are provided on one of the six faces of the case portion 162. In other words, both the external positive electrode terminal 166 and the external negative electrode terminal 167 are provided on one of three faces arranged along three planes that intersect each other. The external positive terminal 166 and the external negative terminal 167 may be provided on the surface other than the upper surface 162a. The external positive terminal 166 and the external negative terminal 167 may be provided on the lower surface 162b and any one of the four side faces 162c, 162d, 162e, and 162f. Since the external positive electrode terminal 166 and the external negative electrode terminal 167 are provided on one surface of the case portion 162, it is easy to connect the external positive electrode terminal 166 and the external negative electrode terminal 167 to the power supply circuit of the straddle type vehicle 1 or the like. For the operation of the DC charger. The casing portion 162 houses 16 metal box type batteries 161, a metal box type battery fixing portion 163, a connecting portion 164, and a balancing circuit 165. The housing portion 162 can also accommodate the battery management device described above. For example, the battery management device can also be mounted to the cover 1622. Furthermore, the battery management device may not be housed in the casing portion 162. The battery management device may be housed in only a part of the casing portion 162. The battery management device may also be disposed outside the housing portion 162. The metal box type battery fixing portion 163 has two metal box type battery fixing plates 1631 and 1632. The metal box type battery fixing plate 1631 is a plate-like member in which 16 holes 1631a are formed. The metal box type battery fixing plate 1632 is a plate-like member in which 16 holes 1632a are formed. Two metal box type battery fixing plates 1631 and 1632 are disposed on both sides of the 16 metal box type batteries 161. For the 16 holes 1631a of the metal case type battery fixing plate 1631, one end of one of the 16 metal case type batteries 161 is inserted. For the 16 holes 1632a of the metal case type battery fixing plate 1632, the other end portions of the 16 metal case type batteries 161 are inserted, respectively. Thereby, the metal box type battery fixing portion 163 fixes the 16 metal box type batteries 161 to each other. In a state where the 16 metal cassette type batteries 161 are fixed to the metal case type battery fixing portion 163, a space is formed between the adjacent metal case type batteries 161. The metal box type battery fixing portion 163 is not electrically connected to the plurality of lithium ion batteries 161. The 16 metal case type batteries 161 are arranged in a state of being arranged in four rows. That is, each row is composed of four metal box type batteries 161. The four metal box type batteries 161 constituting the first row each have a positive electrode terminal at a lower end portion thereof. The four metal box type batteries 161 constituting the first row have negative electrode terminals at the upper end portions thereof, respectively. The four metal cassette type batteries 161 constituting the second row respectively have positive electrode terminals at their upper ends. The four metal box type batteries 161 constituting the second row each have a negative electrode terminal at a lower end portion thereof. The four metal cassette type batteries 161 constituting the third row each have a positive electrode terminal at a lower end portion thereof. The four metal box type batteries 161 constituting the third row respectively have negative electrode terminals at their upper ends. The four metal box type batteries 161 constituting the fourth row respectively have positive electrode terminals at their upper ends. The four metal cassette type batteries 161 constituting the fourth row each have a negative electrode terminal at a lower end portion thereof. The connecting portion 164 has five connecting plates 1641, 1642, 1643, 1644, and 1645. The connecting plates 1641, 1642, 1643, 1644, 1645 are formed of a material having electrical conductivity. The connection plate 1641 is connected to the negative terminal of the four metal cassette type batteries 161 constituting the first row. The connection plate 1642 is connected to the positive terminal of the four metal cassette type batteries 161 constituting the first row. Further, the connecting plate 1642 is connected to the negative terminal of the four metal battery cells 161 constituting the second row. The connection plate 1643 is connected to the positive terminal of the four metal cassette type batteries 161 constituting the second row. Further, the connection plate 1643 is connected to the negative terminal of the four metal cassette type batteries 161 constituting the third row. The connection plate 1644 is connected to the positive terminal of the four metal cassette type batteries 161 constituting the third row. Further, the connecting plate 1644 is connected to the negative terminal of the four metal battery cells 161 constituting the fourth row. The connection plate 1645 is connected to the positive terminal of the four metal cassette type batteries 161 constituting the fourth row. The four metal case type batteries 161 of the first row are connected in parallel to each other by the connection plate 1641 and the connection plate 1642. Thereby, the four metal cassette type batteries 161 of the first row constitute a parallel battery group 1711 which is connected in parallel to each other. The four metal cassette type batteries 161 of the second row are connected in parallel to each other by the connection plate 1642 and the connection plate 1643. Thereby, the four metal cassette type batteries 161 of the second row constitute a parallel battery group 1712 which is connected in parallel to each other. The four metal box type batteries 161 of the third row are connected in parallel to each other by the connecting plate 1643 and the connecting plate 1644. Thereby, the four metal cassette type batteries 161 of the third row constitute the parallel battery group 1713 which are connected in parallel to each other. The four metal box type batteries 161 of the fourth row are connected in parallel to each other by a connecting plate 1644 and a connecting plate 1645. Thereby, the four metal cassette type batteries 161 of the fourth row constitute the parallel battery group 1714 which are connected in parallel to each other. Further, the four metal box type batteries 161 in the first row and the four metal box type batteries 161 in the second row are connected in series by the connecting plate 1642. In other words, the parallel battery group 1711 and the parallel battery group 1712 are connected in series by the connection plate 1642. The four metal cassette type batteries 161 in the second row and the four metal box type batteries 161 in the third row are connected in series by the connection plate 1643. In other words, the parallel battery group 1712 and the parallel battery group 1713 are connected in series by the connection plate 1643. The four metal cassette type batteries 161 of the third row and the four metal box type batteries 161 of the fourth row are connected in series by the connection plate 1644. In other words, the parallel battery group 1713 and the parallel battery group 1714 are connected in series by the connection plate 1644. Thereby, the four parallel battery groups 1711, 1712, 1713, and 1714 are connected in series to each other. The metal box type battery fixing portion 163 fixes the four parallel battery groups 1711, 1712, 1713, and 1714 in series. The connection plate 1641 is connected to the external negative terminal 167 via a cable (not shown). Thereby, the negative terminal of the four metal battery cells 161 of the first row is electrically connected to the external negative terminal 167. The connection plate 1645 is connected to the external positive terminal 166 via a cable (not shown). Thereby, the positive terminal of the four metal battery cells 161 of the fourth row is electrically connected to the external positive terminal 166. The balancing circuit 165 suppresses unevenness in the progress of charging of the 16 metal-cassette batteries 161. In general, when a plurality of batteries connected in series are charged, there is a case where voltages of a plurality of batteries are deviated. Therefore, there is a case where the degree of progress of charging of a plurality of batteries varies. The balancing circuit 165 reduces the deviation of the voltage of the metal cassette type battery 161 by, for example, discharging the current of the metal cassette type battery 161 to the resistor for each of the metal case type batteries 161. Furthermore, the battery pack 16 may not have the balancing circuit 165. Specific examples of the embodiment of the present invention exhibit the following effects in addition to the effects of the embodiments of the present invention described above. By accommodating the electrolytic solution 1615 in the metal case 1613, the metal case 1613 does not expand even if the electrolytic solution 1615 is volatilized. Therefore, as the electrolytic solution 1615, an electrolyte having a high volatility can be used. The electrolyte with higher volatility is less likely to solidify or freeze at low temperatures. Therefore, in the case of using an electrolyte which is hard to solidify or freeze at a low temperature, the battery pack 16 having a plurality of metal cassette type batteries 161 can be used in a low temperature environment. Therefore, even if the battery pack 16 having the plurality of metal-cassette batteries 161 is mounted on the straddle-type vehicle and the battery pack is charged or discharged with a large current in a state where the battery is mounted at a lower temperature, the battery can be suppressed. Deterioration of metal box type batteries. In other words, even in the environment in which the battery pack mounted on the straddle type vehicle is used, deterioration of the metal case type battery (lithium ion battery) caused by charging or discharging in a low temperature environment can be suppressed. By using an electrolyte which is not frozen at -20 ° C as an electrolytic solution, the battery pack 16 having a plurality of metal cassette type batteries 161 can be used in a low temperature environment of about -20 ° C. Therefore, even if the battery pack 16 having the plurality of metal battery cells 161 is mounted on the straddle-type vehicle 1 and is charged at a low temperature of about -20 ° C or discharged at a high current, the metal battery 161 can be suppressed. Deterioration. Thereby, even in the use environment of the battery pack 16 mounted on the straddle type vehicle 1, deterioration of the metal cassette type battery 161 can be further suppressed. Both of the metal case type battery 161 and the metal case type battery fixing portion 163 are housed in the case portion 162. Thereby, a plurality of metal box type batteries 161 can be protected from water or moisture or the like. Therefore, deterioration of the metal cassette type battery 161 can be suppressed. Thereby, even when the battery pack 16 is mounted on the straddle-type vehicle 1 which does not have an engine room or a motor room, deterioration of the metal-cassette battery 161 can be suppressed. In other words, even in the use environment of the battery pack mounted on the straddle-type vehicle 1, deterioration of the metal-cassette battery 161 can be further suppressed. Moreover, it is easy to move a plurality of metal case type batteries 161 and metal case type battery fixing portions 163 together. Therefore, the operation of the battery pack 16 becomes easier. Therefore, the battery pack 16 is easily mounted on the straddle type vehicle 1. Moreover, the versatility of the battery pack 16 is improved. A plurality of parallel battery groups 171 are connected in series to each other. By increasing the number of parallel battery groups 171, the output voltage of the battery pack 16 can be made high. Each of the plurality of parallel battery groups 171 includes at least two metal box type batteries 161 connected in parallel with each other. That is, the plurality of metal box type batteries included in the battery pack 16 include the metal box type battery 161 which are connected in parallel to each other. Therefore, the output current of the battery pack 16 becomes larger as compared with the case where a plurality of metal battery cells 161 of the battery pack 16 are connected in series in one line. If the output current of the battery pack 16 becomes large, the capacity of the battery pack 16 also becomes large. The greater the number of metal box type batteries 161 connected in parallel with each other, the larger the output current and capacity of the battery pack 16. Since the capacity of the battery pack 16 is large, the charging frequency of the battery pack 16 can be reduced. As a result, deterioration of the metal cassette type battery 161 can be suppressed. The battery pack 16 can be used in an environment where the output voltage, output current, and capacity required for the battery pack 16 are relatively large. A plurality of metal box type batteries 161 are fixed to each other by the metal box type battery fixing portion 163. Thereby, it is easy to move a plurality of metal cassette type batteries 161 together. Therefore, the operation of the battery pack 16 becomes easy. Further, a space is formed between the adjacent metal battery cells 161. Thereby, heat generated during charging and discharging of the plurality of metal battery cells 161 can be moved to the space. In addition, since the metal case 1613 of the metal case type battery 161 is made of metal, the heat dissipation property of the metal case type battery 161 is high. Thereby, the temperature rise of the plurality of metal cassette type batteries 161 can be suppressed during charging and discharging of the plurality of metal case type batteries 161. <Modifications of Embodiments of the Present Invention> The present invention is not limited to the specific embodiments of the above-described embodiments and the embodiments, and various modifications can be made within the scope of the claims. Hereinafter, a modified example of the embodiment of the present invention will be described. Incidentally, the same components as those of the above-described configuration are denoted by the same reference numerals, and their description will be appropriately omitted. Specific examples of the above embodiments and the following modifications can be combined as appropriate. In the specific example of the above embodiment, the plurality of metal box type batteries 161 are connected in a plurality of manners including at least two metal box type batteries connected in parallel with each other. The parallel battery group 171 of 161 is connected in series. However, the connection form of the plurality of metal case type batteries of the present invention is not limited to this aspect. The connection state of the plurality of metal-casing type batteries of the present invention may be any one of a plurality of metal-casing type batteries connected in series with any of a plurality of metal-casing type batteries. In the case where a plurality of metal-cassette batteries of the present invention constitute a plurality of parallel battery groups, the number of parallel battery groups is not particularly limited. The connection state of the plurality of metal box type batteries of the present invention may also be a state in which a plurality of metal box type batteries are connected in series in one line. When a plurality of metal cassette type batteries are connected in series in one line, the output voltage of the battery pack becomes higher than when a plurality of metal cassette type batteries are connected in series and in parallel. Therefore, the number of metal-cassette batteries of the battery pack can be reduced while ensuring the output voltage required for the battery pack. Thereby, the battery pack can be made compact and lightweight. The battery pack can be used in an environment where the output current and capacity required for the battery pack are relatively small and the output voltage required for the battery pack is relatively large. The connection pattern of the plurality of metal box type batteries of the present invention may also be a state in which a plurality of series battery groups including at least two metal box type batteries connected in series to each other are connected in parallel. An example of this is shown in FIG. Symbol 172 of Figure 7 represents a series battery pack. In the case where a plurality of metal cassette type batteries of the present invention constitute a plurality of series battery groups, the number of series battery groups is not particularly limited. By increasing the number of metal cartridge type batteries constituting the series battery group, the output voltage of the battery pack can be made high. A plurality of series battery groups are connected in parallel with each other. That is, the plurality of metal box type batteries included in the battery pack include metal box type batteries connected in parallel to each other. Therefore, the output current of the battery pack becomes larger as compared with the case where a plurality of metal box type batteries of the battery pack are connected in series in one line. If the output current of the battery pack becomes large, the capacity of the battery pack also becomes large. The greater the number of metal box type batteries connected in parallel with each other, the larger the output current and capacity of the battery pack. Since the capacity of the battery pack is large, the charging frequency of the battery pack can be reduced. As a result, deterioration of the metal cassette type battery (lithium ion battery) can be suppressed. The battery pack can be used in a battery environment where the output voltage, output current, and capacity required for the battery pack are relatively large. The connection state of the plurality of metal box type batteries of the present invention may also be a state in which a plurality of series parallel groups are connected in series, and the series parallel group is a plurality of series including at least two metal box type batteries connected in series with each other. The battery packs are obtained by connecting in parallel. The connection state of the plurality of metal box type batteries of the present invention may also be a state in which a plurality of parallel series groups are connected in parallel, and the parallel series group includes a plurality of parallels including at least two metal box type batteries connected in parallel with each other. The battery packs are obtained by connecting in series. The connection state of the plurality of metal box type batteries of the present invention may also be a state in which a plurality of parallel parallel groups are connected in series, and the parallel parallel group is a plurality of parallel connected with at least two metal box type batteries connected in parallel with each other. The battery packs are obtained by connecting in parallel. The plurality of metal box type batteries may also include metal box type batteries that are only connected in series with respect to other metal box type batteries included in the battery pack. The plurality of metal box type batteries may also include metal box type batteries that are only connected in parallel with respect to other metal box type batteries included in the battery pack. In the connection aspect of the plurality of metal case type batteries of the present invention, the number of the metal case type batteries connected in series to each other is not limited. In the aspect in which the plurality of metal cassette type batteries of the present invention are connected in series, the number of metal cassette type batteries connected in parallel with each other is not limited. In the connection aspect of the plurality of metal box type batteries of the present invention, the number of the metal box type batteries connected in series may be the same or different. For example, when a plurality of metal cassette type batteries have two battery packs connected in series, the number of metal box type batteries constituting the first series battery group may be the same as the number of metal box type batteries constituting the second series battery group. Can be different. In the connection aspect of the plurality of metal box type batteries of the present invention, the number of the metal box type batteries connected in parallel may be the same or different. For example, when a plurality of metal battery cells have two parallel battery groups, the number of metal battery cells constituting the first parallel battery group may be the same as the number of metal battery cells constituting the second parallel battery group. Can be different. Modifications relating to the metal box type fixing portion The metal box type battery fixing portion 163 of the specific example of the above embodiment has two metal box type battery fixing plates 1631 and 1632. However, the configuration of the metal box type battery fixing portion is not limited to this aspect. For example, the metal box type battery fixing portion may also include one plate member. The metal case type battery fixing portion may be constituted by only one of the metal case type battery fixing plates 1631 and 1632. Further, the metal box type battery fixing portion may include two or more plate members. The metal box type battery fixing portion may not be a plate member. In the specific example of the above embodiment, one end of one of the plurality of metal case type batteries 161 is inserted into each of the 16 holes 1631a of the metal case type battery fixing plate 1631. The other end portions of the plurality of metal case type batteries 161 are inserted into the 16 holes 1632a of the metal case type battery fixing plate 1632, respectively. Thereby, a plurality of metal cassette type batteries 161 are fixed to each other. However, the manner in which a plurality of metal box type batteries are fixed to each other by the metal box type battery fixing portion is not limited to this aspect. Further, for example, a plurality of metal box type batteries may be fixed to a plurality of grooves (recesses) formed in the metal case type battery fixing portion, and a plurality of metal case type batteries may be fixed to each other. In the specific example of the above embodiment, the metal battery cells 161 are fixed to each other in a state in which a space is formed between the adjacent metal battery cells 161. However, in the present invention, the state in which the plurality of metal box type batteries are fixed to each other by the metal box type battery fixing portion is not limited to this aspect. Further, a plurality of metal case type batteries may be fixed to each other in a state where at least two of the plurality of metal case type batteries are not formed with each other. In the specific example of the above embodiment, the metal box type battery fixing portion 163 may be electrically connected to a plurality of metal box type batteries. However, in the present invention, the metal case type battery fixing portion can also serve as a connection portion for electrically connecting a plurality of metal case type batteries to each other. Thereby, the number of parts can be reduced. As a result, the battery pack can be made lighter and smaller. On the other hand, when a metal case type battery fixing portion is separately provided in addition to the connection portion, the plurality of metal case type batteries can be fixed to each other by the metal case type battery fixing portion, and then the connection portion can be electrically connected to the connection portion. Metal box type battery. Therefore, it is easy to connect the metal box type battery to the connection portion. Modifications relating to the casing portion In the battery pack 16 of the specific example of the above embodiment, a plurality of metal box type batteries 161 and a metal box type battery fixing portion 163 are housed in the casing portion 162. However, in the present invention, the aspect of the battery pack is not limited to this aspect. The plurality of metal box type batteries and the metal box type battery fixing portion may not be housed in the casing portion. One of the plurality of metal case type batteries may be housed in the case portion, and the remaining metal case type battery is not housed in the case portion. One of the metal case type battery fixing portions may be housed in the case portion, and the other portion of the metal case type battery fixing portion may not be housed in the case portion. A plurality of metal case type batteries and a metal case type battery fixing portion may be housed in a plurality of case portions. For example, one of the plurality of metal box type batteries may be housed in the first case portion, and the remaining metal case type battery may be housed in the second case portion. The casing portion 162 of the specific example of the above embodiment includes a main body 1621 and a cover 1622. The body 1621 is separable from the cover 1622. However, the aspect of the casing portion of the present invention is not limited to this aspect. It is also possible that the body of the housing portion and the cover cannot be separated. The housing portion may also include more than three accessories. In the specific example of the above embodiment, the casing portion 162 of the battery pack 16 is a substantially rectangular parallelepiped casing. However, in the present invention, the casing portion of the battery pack may be a box body of a polyhedron other than a rectangular parallelepiped shape. In this case, the casing portion also has a plurality of faces arranged along a plurality of planes that intersect each other. In the case where the casing is a polyhedron other than a rectangular parallelepiped, the number of the faces is at least four. Modification of Configuration of a Number of Metal Box Type Batteries In the present invention, the metal case 1613 has a cylindrical shape. However, the shape of the metal case is not limited to the cylindrical shape. For example, the metal case may also be box-shaped (cuboid). For example, it may be a box made of metal in a box shape, and the positive electrode and the negative electrode may be housed in a box-shaped metal case in a state of being wound around a specific axis. Further, the metal case may be in the form of a flat plate. For example, the positive electrode and the negative electrode may be housed in a flat state in a flat metal case. For example, the positive electrode of the metal case type battery and the negative electrode may be laminated in a flat metal case. For example, the positive electrode and the negative electrode of the metal-box type battery may be housed in a state of being wound around a specific axis in a box made of a flat metal. In the specific example of the above embodiment, each of the plurality of metal box type batteries 161 has a positive electrode 1611, a negative electrode 1612, and an electrolytic solution 1615. However, in the present invention, the metal case type battery may be a metal case type battery having a positive electrode, a negative electrode, and a solid electrolyte. In this case, the solid electrolyte is in contact with both the positive electrode and the negative electrode. The metal case type battery of the present invention may be a metal case type battery obtained by accommodating a positive electrode, a negative electrode, and a solid electrolyte in a metal case. Further, the plurality of lithium ion batteries 161 may include a metal case type battery having a positive electrode, a negative electrode, and an electrolytic solution, and a metal case type battery having a positive electrode, a negative electrode, and a solid electrolyte. In the specific example of the above embodiment, the plurality of metal box type batteries 161 have the same configuration. However, in the present invention, the plurality of lithium ion batteries may also include at least two lithium ion batteries having different configurations. That is, a plurality of lithium ion batteries may also include two or more types of lithium ion batteries. In the specific example of the above embodiment, the plurality of metal cartridge type batteries 161 have the same positive electrode active material. However, in the present invention, the positive electrode active materials of at least two of the plurality of metal-box type batteries may be different from each other. In other words, the number of positive electrode active materials of the plurality of metal-cassette batteries may be two or more. In the specific example of the above embodiment, the negative electrode active materials of the plurality of metal battery cells 161 are of the same type. However, in the present invention, the negative electrode active materials of at least two of the plurality of metal-box type batteries may be different from each other. In other words, the number of the negative electrode active materials of the plurality of metal-cassette batteries may be two or more. For example, in the negative electrode of at least two of the plurality of metal-box type batteries, the average interlayer distance of the plurality of carbon layers may be different from each other. In the specific example of the above embodiment, the electrolytes of the plurality of metal battery cells 161 are of the same type. However, in the present invention, the electrolytes of at least two of the plurality of metal-box type batteries may be different from each other. In other words, the number of electrolytes of the plurality of metal-cassette batteries may be two or more. Further, in the case where a plurality of metal case type batteries have a positive electrode, a negative electrode, and a solid electrolyte, the solid electrolytes of the plurality of metal case type batteries may be of the same type. Further, the solid electrolytes of at least two of the plurality of metal-cassette batteries may be different from each other. In other words, the number of solid electrolytes of the plurality of metal-cassette batteries may be two or more. Further, the plurality of lithium ion batteries 161 may include one or more metal battery cells having a positive electrode, a negative electrode, and an electrolyte, and one or more metal battery cells having a positive electrode, a negative electrode, and a solid electrolyte. In this case, at least two of the plurality of metal-box type batteries having the positive electrode, the negative electrode, and the electrolytic solution may have the same electrolyte type or different from each other. Further, at least two of the plurality of metal-box type batteries including the positive electrode, the negative electrode, and the solid electrolyte may have the same type of solid electrolytes, or may be different from each other. ◆ Temperature Adjustment Device In a specific example of the above embodiment, a temperature adjustment device may be housed in the casing portion. The temperature adjustment device adjusts the temperature of the space formed between adjacent lithium ion batteries. The temperature adjustment device may be, for example, a fan for air cooling. The temperature adjustment device can also be, for example, cold water or warm water. The temperature adjustment device can also be, for example, a heater. ◆Modification Example of Device for Mounting Battery Pack The battery pack 16 of the specific example of the above embodiment is mounted on a straddle type vehicle 1 having an engine. However, the battery pack of the present invention can be mounted on a straddle type vehicle using a motor as a drive source, or can be mounted on a straddle type vehicle using a motor and an engine as a drive source. The battery pack of the present invention can also be mounted on a power consuming device other than a straddle type vehicle. The electric power stored in the battery pack is used for driving the power consuming device. The type of power consuming device for mounting the battery pack is not particularly limited. The power consuming device may or may not be a vehicle. The vehicle may be an engine as a driving source, a motor as a driving source, and an engine and a motor as a driving source. When the battery pack of the present invention is mounted on a vehicle including a motor in a drive source, the battery pack supplies electric power to the motor (drive source). The vehicle may be a person traveling on land, a person traveling on the water, and a person traveling in the water, and may also be a person traveling in the air. Vehicles that travel on land are, for example, four-wheel vehicles, two-wheel vehicles, three-wheelers, and snowmobiles. Vehicles that travel on land may also be those with more than four wheels. Four-wheeled vehicles are, for example, passenger cars, ATVs (All Terrain Vehicles), ROVs (Recreational Off-highway Vehicles), golf carts, and stackers. The two-wheeled vehicle may be a vehicle having two wheels arranged in the front-rear direction, or a vehicle having two wheels arranged in the left-right direction. As an example of the former, for example, a locomotive (system bicycle), a speed skating, a light locomotive with a pedal, a bicycle, and the like. A tricycle can be a vehicle with 2 front wheels or 2 vehicles with rear wheels. Vehicles that travel on water are, for example, boats, jet skis, and the like. Vehicles that travel in water are, for example, submarines. Vehicles that travel in the air are, for example, airplanes, helicopters, remotely piloted aircraft, and the like. The battery pack of the present invention can be attached or detached with respect to the power consuming device or can not be attached or detached. The battery pack can be charged while being discharged from the power consuming device, or can be charged while being mounted on the power consuming device. ◆Modification relating to charging of the battery pack The battery pack of the present invention may be charged by a charger other than the DC charger for 12 V to 15 V. When the battery pack is charged by a DC charger having a voltage higher than 12 V to 15 V, the battery pack can be used instead of the lead storage battery mounted on a vehicle using a motor as a drive source. [Embodiment] Hereinafter, the characteristics of an example of a metal battery type battery (hereinafter sometimes referred to as a lithium ion battery of the present invention) of the battery pack of the present invention will be described with reference to Figs. 8 to 11 . The lithium ion battery of the present invention has a diameter of 18 mm and a length of 65. A cylindrical lithium-ion battery of 0 mm, the so-called 18650 battery. (1) Discharge characteristics at different current values The lithium ion battery of the example of the present invention was charged by a constant current constant voltage method. The charging current in constant current charging is set to 1 A. The charging voltage under constant voltage charging is set to 4. 2 V. The charge termination current is set to 0. 05 A. After the end of charging, the lithium ion battery of the example of the present invention was subjected to constant current discharge. The respective discharge capacities when the discharge currents in the constant current discharge were set to 1 A, 3 A, 5 A, and 10 A were investigated. The discharge termination voltage is set to 2. 5 V. The discharge current is also referred to as the output current. Fig. 8 shows the discharge characteristics of the lithium ion battery when the discharge current is 1 A, 3 A, 5 A and 10 A. The vertical axis of Fig. 8 represents the voltage of the lithium ion battery, and the horizontal axis of Fig. 8 represents the discharge capacity of the lithium ion battery. According to Fig. 8, when the discharge current is any one of 1 A, 3 A, 5 A, and 10 A, the discharge capacity also exceeds 1 Ah. From this, it is understood that the lithium ion battery of the example of the present invention can be utilized even at a high discharge rate. (2) Cyclic characteristics under different temperature environments The cycle characteristics of lithium ion batteries in the following three temperature environments were investigated. The charging and discharging of the lithium ion battery of the present invention were repeated in a temperature environment of 60 °C. The charging and discharging of the lithium ion battery of the example of the present invention were repeated under a temperature environment of -10 °C. The charging and discharging of the lithium ion battery of the example of the present invention were repeated under the assumption of the temperature environment of the four seasons of ASEAN (Association of Southeast Asian Nations). Specifically, it is assumed that the temperature of one year is changed in the order of 40 ° C, 25 ° C, 10 ° C, and 25 ° C. The charge and discharge were counted as one cycle, and the ambient temperature was changed in the order of 40 ° C, 25 ° C, 10 ° C, and 25 ° C every 2,500 cycles. First, in order to make the lithium ion battery fully charged, the lithium ion battery is charged by the constant current constant voltage method. The charging current under constant current charging is set to 1 A. The charging voltage under constant voltage charging is set to 3. 65 V. The charge termination current is set to 0. 05 A. Thereafter, charging and discharging are repeated. The lithium ion battery is set to full charge whenever the 2,500 cycles are completed. When the lithium ion battery is fully charged, the lithium ion battery is charged by a constant current constant voltage method. The charging current under constant current charging is set to 1 A. The charging voltage under constant voltage charging is set to 3. 65 V. The charge termination current is set to 0. 05 A. Fig. 9 shows a pattern of load current for one cycle in the charge and discharge cycle. The vertical axis of Fig. 9 is the load current, and the horizontal axis of Fig. 9 is the time. In Figure 9, when the load current is negative, the lithium ion battery is discharged. In Figure 9, the lithium ion battery is charged when the load current is positive. The pattern of the load current shown in FIG. 9 is generated based on the driving conditions defined in the ECE (Economic Commission for Europe) 40 (ISO (International Organization for Standardization) 6460). The driving conditions specified in ECE40 (ISO6460) are sometimes referred to as ECE40 driving patterns. The so-called ECE40 driving pattern is the European actual fuel efficiency measurement method, that is, the driving pattern in the ECE40 urban circulation mode. The battery capacity of the lithium ion battery was measured for every 2,500 cycles. Specifically, it is carried out by the following method. First, charging is performed by a constant current constant voltage method in a temperature environment of 25 °C. The charging current under constant current charging is set to 1 A. The charging voltage under constant voltage charging is set to 3. 65 V. The charge termination current is set to 0. 05 A. After the end of charging, constant current discharge was performed in a temperature environment of 25 ° C, and the discharge capacity of the lithium ion battery was measured. The discharge current in the constant current discharge was set to 1 A. The discharge termination voltage is set to 2. 5 V. By dividing the discharge capacity of the lithium ion battery every 2,500 cycles by the discharge capacity at the discharge of the first cycle, the specific cycle of the discharge capacity at the discharge of the first cycle is determined. The discharge capacity at the time of discharge. Here, the discharge capacity at the time of discharge at the specific specific cycle with respect to the discharge capacity at the time of discharge at the first cycle is referred to as an initial capacity ratio. This initial capacity ratio is sometimes referred to as a capacity retention ratio. The relationship between the initial capacity ratio and the number of cycles is shown in FIG. The vertical axis of Fig. 10 is the initial capacity ratio, and the horizontal axis of Fig. 10 is the number of cycles. According to Fig. 10, the following will be known. The initial capacity ratio of the 20000th cycle is 95% at a low temperature environment of -10 ° C and a temperature environment of the four seasons of ASEAN. Further, the initial capacity ratio of the low temperature environment of -10 ° C and the initial capacity ratio of the temperature environment of the four seasons of ASEAN are assumed to be similar. From this, it is understood that the lithium ion battery of the example of the present invention has the same durability as the temperature environment of the four seasons assumed to be ASEAN even if it is repeatedly charged and discharged in a low temperature environment of -10 °C. Moreover, in the high temperature environment of 60 ° C, the initial capacity ratio of the 20000 cycle is also 80%. Accordingly, it can be said that the lithium ion battery of the example of the present invention has high durability even in a high temperature environment. According to the above, the lithium ion battery of the example of the present invention has high durability regardless of the low temperature environment or the high temperature environment. That is, the lithium ion battery of the example of the present invention is not easily deteriorated in a low temperature environment or in a high temperature environment. Therefore, the lithium ion battery of the present invention has a high degree of freedom in use environment. (3) Comparison of cycle characteristics between the inventive example and the comparative example As a comparative example, a lithium ion battery in which the positive electrode active material was lithium iron phosphate and the negative electrode active material was graphite was used. The charging and discharging of the lithium ion battery of the example of the present invention and the lithium ion battery of the comparative example were repeated in an environment of 45 ° C. Specifically, the operation is repeated as follows: after constant current constant voltage charging is performed, constant current discharge is performed. The standby time from the end of charging to the start of discharge is set to 30 minutes. The standby time from the end of discharge to the start of charging is set to 30 minutes. The charging current under constant current charging is set to 3 A. The charging voltage under constant voltage charging is set to 3. 6 V. The charge termination current is set to 0. 05 A. The discharge current of the constant current discharge was set to 3 A. The discharge termination voltage is set to 2. 5 V. After the end of charging and discharging in a specific cycle, the discharge capacity of the lithium ion battery was measured by the following method. First, charging is performed by a constant current constant voltage method in an environment of 25 °C. The charging current under constant current charging is set to 1 A. The charging voltage under constant voltage charging is set to 3. 65 V. The charge termination current is set to 0. 05 A. Thereafter, constant current discharge was performed in an environment of 25 ° C, and the discharge capacity of the lithium ion battery was measured. The discharge current was set to 1 A. The discharge termination voltage is set to 2. 5 V. The discharge capacity at the time of discharge in the first cycle and the discharge capacity at the time of discharge after the end of the specific cycle were measured. By dividing the discharge capacity at the time of discharge after the end of the specific cycle by the discharge capacity at the discharge of the first cycle, the specific cycle after the discharge capacity at the discharge of the first cycle is determined. The discharge capacity at the time of discharge. Here, the discharge capacity at the time of discharge after the end of the specific cycle with respect to the discharge capacity at the time of discharge in the first cycle is referred to as an initial capacity ratio. The relationship between the initial capacity ratio and the number of cycles is shown in FIG. The vertical axis of Fig. 11 is the initial capacity ratio, and the horizontal axis of Fig. 11 is the number of cycles. According to Fig. 11, in each cycle, the initial capacity ratio of the lithium ion battery of the example of the present invention was larger than the initial capacity ratio of the lithium ion battery of the comparative example. Further, the initial capacity of the lithium ion battery of the present invention was about 99% in 100 cycles. On the other hand, the initial capacity of the lithium ion battery of the comparative example was less than about 96% in 100 cycles. It is understood that the lithium ion battery of the example of the present invention can suppress deterioration more than the lithium ion battery of the comparative example. According to the above, the lithium ion battery of the example of the present invention can suppress deterioration even if it is repeatedly charged and discharged in a low temperature environment and a high temperature environment. Moreover, the lithium ion battery of the example of the present invention can suppress deterioration even if charging and discharging are repeated over a long period of time. Therefore, the battery pack having the plurality of lithium ion batteries of the example of the present invention can suppress the deterioration of the lithium ion battery even in the use environment of the battery pack mounted on the straddle type vehicle. In addition, the battery pack of Japanese Patent Application No. 2017-038284, which is the basis of the present application, is included in the battery pack of the present specification. The lithium ion battery 161 in this basic application corresponds to the metal case type battery 161 or the lithium ion battery 161 of the present specification. The can 1613 in the basic application corresponds to the metal case 1613 or the metal case 1613 of the present specification. The box portion 162 in the basic application corresponds to the casing portion 162 of the present specification. The can battery fixing portion 163 in the basic application corresponds to the metal case type battery fixing portion 163 of the present specification.

1‧‧‧跨坐型車輛1‧‧‧Sitting vehicle

2‧‧‧前輪2‧‧‧front wheel

3‧‧‧後輪3‧‧‧ Rear wheel

10‧‧‧引擎10‧‧‧ engine

11‧‧‧啟動馬達11‧‧‧Starting motor

16‧‧‧電池組16‧‧‧Battery Pack

161‧‧‧金屬盒型電池(鋰離子電池)161‧‧‧Metal box type battery (lithium ion battery)

162‧‧‧殼體部162‧‧‧Shell Department

162a‧‧‧上表面162a‧‧‧ upper surface

162b‧‧‧下表面162b‧‧‧ lower surface

162a‧‧‧上表面162a‧‧‧ upper surface

162b‧‧‧下表面162b‧‧‧ lower surface

162c‧‧‧側面162c‧‧‧ side

162d‧‧‧側面162d‧‧‧ side

162e‧‧‧側面162e‧‧‧ side

162f‧‧‧側面162f‧‧‧ side

163‧‧‧金屬盒型電池固定部163‧‧‧Metal box type battery fixing part

164‧‧‧連接部164‧‧‧Connecting Department

165‧‧‧平衡電路165‧‧‧balanced circuit

166‧‧‧外部正極端子166‧‧‧External positive terminal

167‧‧‧外部負極端子167‧‧‧External negative terminal

171‧‧‧並聯電池群171‧‧‧Parallel battery pack

172‧‧‧串聯電池群172‧‧‧Series battery pack

1611‧‧‧正極1611‧‧‧ positive

1612‧‧‧負極1612‧‧‧negative

1613‧‧‧金屬製之盒(金屬盒)1613‧‧‧Metal box (metal box)

1614‧‧‧隔離膜1614‧‧‧Separator

1615‧‧‧電解液1615‧‧‧ electrolyte

1621‧‧‧本體1621‧‧‧ Ontology

1622‧‧‧蓋1622‧‧‧ Cover

1631‧‧‧金屬盒型電池固定板1631‧‧‧Metal box type battery fixing plate

1631a‧‧‧孔1631a‧‧ hole

1632‧‧‧金屬盒型電池固定板1632‧‧‧Metal box type battery fixing plate

1632a‧‧‧孔1632a‧‧ hole

1641‧‧‧連接板1641‧‧‧Connecting plate

1642‧‧‧連接板1642‧‧‧Connecting plate

1643‧‧‧連接板1643‧‧‧Connecting plate

1644‧‧‧連接板1644‧‧‧Connecting plate

1645‧‧‧連接板1645‧‧‧Connecting plate

1711‧‧‧並聯電池群1711‧‧‧Parallel battery pack

1712‧‧‧並聯電池群1712‧‧‧Parallel battery pack

1713‧‧‧並聯電池群1713‧‧‧Parallel battery pack

1714‧‧‧並聯電池群1714‧‧‧Parallel battery pack

16111‧‧‧正極活性物質16111‧‧‧ positive active material

16112‧‧‧集電體16112‧‧‧ Collector

16121‧‧‧負極活性物質16121‧‧‧Negative active material

16121a‧‧‧碳層16121a‧‧‧carbon layer

16121b‧‧‧碳層16121b‧‧‧carbon layer

16121c‧‧‧碳層16121c‧‧‧carbon layer

16122‧‧‧集電體16122‧‧‧ Collector

D‧‧‧直徑D‧‧‧diameter

L‧‧‧距離L‧‧‧ distance

圖1係表示本發明之實施形態之電池組之概略構成的模式圖。 圖2係表示本發明之實施形態之具體例之電池組之概略構成的模式圖。 圖3係本發明之實施形態之具體例之電池組所具有之複數個鋰離子電池的電路圖。 圖4係表示鋰離子電池之內部結構之立體圖。 圖5係鋰離子電池之模型圖。 圖6係電池組之分解立體圖。 圖7係本發明之實施形態之變更例之電池組所具有之複數個鋰離子電池的電路圖。 圖8係表示25℃之環境下之鋰離子電池之放電特性的曲線圖。 圖9係表示1次循環劣化試驗中之鋰離子電池之電流之曲線圖。 圖10係表示於特定之溫度環境下保存鋰離子電池時之鋰離子電池之初始容量比之曲線圖。 圖11係表示於45℃之環境下反覆進行充電及放電時之鋰離子電池之初始容量比的曲線圖，且係一併表示本發明例之鋰離子電池之初始容量比與比較例之鋰離子電池之初始容量比之曲線圖。Fig. 1 is a schematic view showing a schematic configuration of a battery pack according to an embodiment of the present invention. Fig. 2 is a schematic view showing a schematic configuration of a battery pack of a specific example of the embodiment of the present invention. Fig. 3 is a circuit diagram of a plurality of lithium ion batteries included in a battery pack of a specific example of the embodiment of the present invention. Fig. 4 is a perspective view showing the internal structure of a lithium ion battery. Figure 5 is a model diagram of a lithium ion battery. Fig. 6 is an exploded perspective view of the battery pack. Fig. 7 is a circuit diagram of a plurality of lithium ion batteries included in a battery pack according to a modification of the embodiment of the present invention. Fig. 8 is a graph showing the discharge characteristics of a lithium ion battery in an environment of 25 °C. Fig. 9 is a graph showing the current of a lithium ion battery in a one-cycle deterioration test. Figure 10 is a graph showing the initial capacity ratio of a lithium ion battery when a lithium ion battery is stored under a specific temperature environment. Figure 11 is a graph showing the initial capacity ratio of a lithium ion battery when charging and discharging are repeatedly performed in an environment of 45 ° C, and shows the initial capacity ratio of the lithium ion battery of the example of the present invention and the lithium ion of the comparative example. A plot of the initial capacity ratio of the battery.

Claims (10)

一種電池組，其係具有相互電性連接之複數個鋰離子電池者，且 上述複數個鋰離子電池之各者係金屬盒型電池，且該金屬盒型電池具有： 1個正極； 1個負極； 電解液或固體電解質；及 金屬製之盒，其收容上述1個正極、上述1個負極、及上述電解液或固體電解質；且 上述複數個金屬盒型電池之各者係與上述複數個金屬盒型電池中之任一者串聯連接， 上述正極具有橄欖石結構之正極活性物質， 上述負極具有負極活性物質，該負極活性物質包含經積層之複數個碳層，且上述複數個碳層之平均層間距離為鋰原子之直徑以上， 上述電池組具有金屬盒型電池固定部， 該金屬盒型電池固定部係將上述複數個金屬盒型電池相互固定。A battery pack having a plurality of lithium ion batteries electrically connected to each other, and each of the plurality of lithium ion batteries is a metal box type battery, and the metal box type battery has: 1 positive electrode; 1 negative electrode An electrolyte or a solid electrolyte; and a metal case for accommodating the one positive electrode, the one negative electrode, and the electrolyte or solid electrolyte; and each of the plurality of metal-cassette batteries and the plurality of metals Any one of the battery cells is connected in series, the positive electrode has a positive active material of an olivine structure, and the negative electrode has a negative active material, and the negative active material includes a plurality of laminated carbon layers, and the average of the plurality of carbon layers The interlayer distance is equal to or larger than the diameter of the lithium atom, and the battery pack has a metal box type battery fixing portion that fixes the plurality of metal box type batteries to each other. 如請求項1之電池組，其中 於上述複數個金屬盒型電池之至少1個金屬盒型電池中， 上述1個正極、上述1個負極及上述電解液被收容於上述金屬盒型電池， 上述電解液係於-20℃不凍結之電解液。The battery pack according to claim 1, wherein the one positive electrode, the one negative electrode, and the electrolytic solution are accommodated in the metal battery type battery, in the at least one metal battery type battery of the plurality of metal battery cells. The electrolyte was an electrolyte that did not freeze at -20 °C. 如請求項1或2之電池組，其具有殼體部， 該殼體部收容上述複數個金屬盒型電池及上述金屬盒型電池固定部之兩者。The battery pack according to claim 1 or 2, further comprising a casing portion accommodating the plurality of metal box type batteries and the metal box type battery fixing portion. 如請求項3之電池組，其具有： 1個外部正極端子，其以可自上述殼體部之外部連接之狀態設置於上述殼體部，且與上述複數個金屬盒型電池中之至少1個金屬盒型電池所具有之至少1個上述正極電性連接；及 1個外部負極端子，其以可自上述殼體部之外部連接之狀態設置於上述殼體部，且與上述複數個金屬盒型電池中之至少1個金屬盒型電池所具有之至少1個上述負極電性連接。A battery pack according to claim 3, comprising: one external positive terminal which is provided in the casing portion in a state connectable from the outside of the casing portion, and at least one of the plurality of metal-cassette batteries At least one of the positive electrodes is electrically connected to each of the metal battery cells, and one external negative terminal is provided in the casing portion in a state connectable from the outside of the casing portion, and to the plurality of metals At least one of the above-mentioned negative electrodes of at least one of the metal battery cells of the battery type is electrically connected. 如請求項4之電池組，其中 上述殼體部係具有沿著相互交叉之複數個平面分別配置之複數個面之箱體， 上述1個外部正極端子及上述1個外部負極端子均設置於上述複數個面中之任一個面。The battery pack according to claim 4, wherein the housing portion has a plurality of surfaces arranged along a plurality of planes intersecting each other, and the one external positive terminal and the one external negative terminal are both provided Any of a number of faces. 如請求項1至5中任一項之電池組，其中 上述複數個金屬盒型電池串聯連接成1行， 上述金屬盒型電池固定部係 將上述複數個金屬盒型電池以串聯連接成1行之狀態加以固定。The battery pack according to any one of claims 1 to 5, wherein the plurality of metal cassette type batteries are connected in series in a row, and the metal box type battery fixing unit connects the plurality of metal box type batteries in series to form one line. The state is fixed. 如請求項1至5中任一項之電池組，其中 上述複數個金屬盒型電池構成複數個串聯電池群，該串聯電池群包含相互串聯連接之至少2個金屬盒型電池， 上述複數個串聯電池群係相互並聯連接， 上述金屬盒型電池固定部係 將複數個串聯電池群以並聯連接之狀態加以固定。The battery pack according to any one of claims 1 to 5, wherein the plurality of metal box type batteries constitute a plurality of series battery groups, the series battery group comprising at least two metal box type batteries connected in series to each other, the plurality of series connected The battery packs are connected in parallel to each other, and the metal box type battery fixing portion fixes a plurality of series battery packs in parallel. 如請求項1至5中任一項之電池組，其中 上述複數個金屬盒型電池構成複數個並聯電池群，該並聯電池群包含相互並聯連接之至少2個金屬盒型電池， 上述複數個並聯電池群係相互串聯連接， 上述金屬盒型電池固定部係將複數個並聯電池群以串聯連接之狀態加以固定。The battery pack according to any one of claims 1 to 5, wherein the plurality of metal box type batteries constitute a plurality of parallel battery groups, the parallel battery group comprising at least two metal box type batteries connected in parallel with each other, the plurality of parallel batteries The battery packs are connected in series to each other, and the metal box type battery fixing portion fixes a plurality of parallel battery groups in a state of being connected in series. 如請求項1至8中任一項之電池組，其 可利用12 V～15 V用之直流充電器進行充電。A battery pack according to any one of claims 1 to 8, which is chargeable by a DC charger for 12 V to 15 V. 如請求項1至9中任一項之電池組，其可搭載於跨坐型車輛，該跨坐型車輛具備： 至少1個前輪； 至少1個後輪；及 驅動源，其至少一部分於車輛前後方向上配置於較上述至少1個前輪更靠後方。The battery pack according to any one of claims 1 to 9, which can be mounted on a straddle type vehicle, the straddle type vehicle having: at least one front wheel; at least one rear wheel; and a driving source at least a part of the vehicle The front-rear direction is disposed further rearward than the at least one front wheel.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113497277A (en) * 2020-03-19 2021-10-12 本田技研工业株式会社 Laminated solid-state battery
TWI832046B (en) * 2020-04-22 2024-02-11 日商山葉發動機股份有限公司 Straddle-type vehicle battery pack and straddle-type vehicle

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4657403B2 (en) * 1999-07-02 2011-03-23 パナソニック株式会社 Nonaqueous electrolyte secondary battery
JP4963186B2 (en) * 2006-03-31 2012-06-27 パナソニック株式会社 Nonaqueous electrolyte secondary battery
JP2008140638A (en) * 2006-11-30 2008-06-19 Nissan Motor Co Ltd Bipolar battery
JP2011096015A (en) * 2009-10-29 2011-05-12 J&K Car Electronics Corp Current value notification device and oscillation control circuit
KR101809651B1 (en) * 2012-11-23 2017-12-15 주식회사 엘지화학 Electrolyte Solution for Lithium Secondary Battery and Lithium Secondary Battery Comprising The Same
JP2016033898A (en) * 2014-07-31 2016-03-10 株式会社東芝 Nonaqueous electrolyte battery and battery pack
JP2016076317A (en) * 2014-10-03 2016-05-12 日立化成株式会社 Lithium ion secondary battery
CN107408666B (en) * 2015-09-25 2021-01-15 株式会社东芝 Electrode for nonaqueous electrolyte battery, and battery pack

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113497277A (en) * 2020-03-19 2021-10-12 本田技研工业株式会社 Laminated solid-state battery
TWI832046B (en) * 2020-04-22 2024-02-11 日商山葉發動機股份有限公司 Straddle-type vehicle battery pack and straddle-type vehicle

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