JP4743977B2 - Rolled copper alloy foil and manufacturing method thereof - Google Patents

Rolled copper alloy foil and manufacturing method thereof Download PDF

Info

Publication number
JP4743977B2
JP4743977B2 JP2001062814A JP2001062814A JP4743977B2 JP 4743977 B2 JP4743977 B2 JP 4743977B2 JP 2001062814 A JP2001062814 A JP 2001062814A JP 2001062814 A JP2001062814 A JP 2001062814A JP 4743977 B2 JP4743977 B2 JP 4743977B2
Authority
JP
Japan
Prior art keywords
foil
copper alloy
rolled
thickness
annealing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2001062814A
Other languages
Japanese (ja)
Other versions
JP2002266041A (en
Inventor
元久 宮藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobe Steel Ltd
Original Assignee
Kobe Steel Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kobe Steel Ltd filed Critical Kobe Steel Ltd
Priority to JP2001062814A priority Critical patent/JP4743977B2/en
Publication of JP2002266041A publication Critical patent/JP2002266041A/en
Application granted granted Critical
Publication of JP4743977B2 publication Critical patent/JP4743977B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Landscapes

  • Cell Electrode Carriers And Collectors (AREA)

Description

【0001】
【発明の属する技術分野】
本発明は、二次電池、詳しくはリチウムイオン二次電池、ポリマー電池などの負極側集電体電極材料として使用し得る銅合金圧延箔に関する。
【0002】
【従来の技術】
リチウムイオン二次電池やポリマー電池の負極側集電体は厚さ10〜20μm程度のタフピッチ銅圧延箔又は電解銅箔上に、ポリフッ化ビニリデン(PVDF)をN−メチルピロリドンに溶かし、さらに負極活物質となる粉末状黒鉛を混合したペーストを#60のバーコータで厚さ90μm程度塗布した後、130℃で3分間乾燥して製造されている。
【0003】
タフピッチ銅圧延箔又は電解銅箔が負極側集電体として使用される理由は、熱伝導率が大であり充電時に発生する熱を速やかに除去できること、強度の高いものが比較的容易に得られ、活物質塗布工程や乾燥工程において銅箔に負荷される引張り応力に耐えられること、及びイオン化傾向などによる。このようにして製造された負極側集電体は、間にセパレーターを介して正極側集電体(アルミ箔に正極活物質を塗布)と重ねてプレスにより一体化し、巻回される(詳細は省略)。
【0004】
ところで、タフピッチ銅には以下のような問題点が指摘されている。
(1)耐熱性
タフピッチ銅は熱伝導率が高く(導電率98%IACS以上)、冷延の圧下率を上げることで引張強さ450〜475N/mm、耐力420〜450N/mm、伸び0.4〜2%のものが比較的容易に得られる。しかし、タフピッチ銅は酸素を含有して銅箔中に亜酸化銅及び不純物元素の酸化物の粒子を含み、マトリックスに固溶している元素が非常に少なく、また亜酸化銅や不純物の酸化物の界面において回復・再結晶が起りやすいことなどから、無酸素銅やりん脱酸銅と比べても耐熱性がかなり低下する。このため、箔の製造工程において圧下率を上げ、高強度のタフピッチ銅を製造しても室温で長時間保管すると回復・再結晶が起り、経時的な強度低下・伸びの増大などの現象が発生する。このような軟化現象は保管雰囲気の温度が高くなる春〜夏の季節において特に顕著である。
【0005】
このように軟化をおこしたタフピッチ銅圧延箔では、引張り強さが低下しているため、軟化の度合いに応じ、活物質の塗布及び乾燥工程において箔に負荷する張力を変えてやる必要がある。そのため、塗布工程に適用する際に事前に強度確認などの作業が新たに発生し、非常に煩雑である。また、軟化の激しい箔を用いる場合には前記工程における箔の切れや箔の伸びが起きやすく、生産性の低下を招く。さらに、電池に組込まれた後の充放電にともなう発熱によって経時的にタフピッチ銅圧延箔が軟化すると、活物質の膨張収縮による箔の破断、活物質の剥離などが発生し、電池性能を低下させてしまう。
そこで、例えば特開平11−86873号公報では銅にAgを微量添加することにより、特開平11−86872号公報では銅に含まれる酸素量を低減することにより、いずれも室温程度での保管中に回復・再結晶が起こるのを抑制して軟化を防止することが提案されている。
【0006】
保管中に軟化の発生していないタフピッチ銅圧延箔を用いる場合においても、活物質塗布後の乾燥工程における加熱(130℃)によって軟化が発生しやすく、乾燥後の箔を巻き取る場合に箔の伸び、箔の切れが起きることがあり、歩留まり・生産性を低下させる。また、活物質塗布及び乾燥などの工程はコイル状の銅箔を巻戻しながら連続的に処理が行われるが、製造工程中において箔の切断、ラインの動作不良などが発生するとライン停止を余儀なくされることがあり、そのような場合には塗布した活物質の乾燥時間が30分以上となることがある。乾燥工程における工程トラブルにより、乾燥させようとする箔が炉中で長時間滞留すると軟化がより大きくなり、この部分が製品として使えなくなることがある。
また、タフピッチ銅圧延箔の場合、箔の延性低下により、圧延工程及びリチウムイオン二次電池製作時において箔の切れが起き、生産性・歩留りの低下を招くことがあった。
【0007】
(2)焼鈍時の密着
タフピッチ銅圧延箔の製造工程において、焼鈍工程が存在する。焼鈍の目的は軟化であり、またタフピッチ銅は析出型の合金でないので、その焼鈍にはバッチ炉を用いても、あるいは連続焼鈍炉を用いても良い。ところが、板厚が薄いコイルをバッチ炉により焼鈍すると、コイルの巻き締め力によって焼鈍中に互いに隣合う薄板間で焼付きによる密着が発生することがあるため、焼鈍によりコイルの歩留まりが極端に低下することがあり問題となっていた。
【0008】
このような密着を防止するためには、(a)コイルの焼鈍温度を低下させる、(b)コイルの巻き締め力を下げる、(c)密着防止油を塗布して焼鈍する、(d)連続焼鈍を行う等の方法がある。しかしながら、それぞれ次のような問題が存在する。(a)については、軟化の程度が低いため、製造工程における焼鈍の回数が増加し、生産性が低下する、(b)については、コイルが緩く巻かれているため、コイル運搬時に薄板がこすれ合って擦り傷がついて歩留まりが低下しやすい、(c)については、焼鈍後、酸化した密着防止油は除去されにくいため入念な酸洗研磨が必要になる、(d)については、板厚の薄い箔地や箔の連続焼鈍が可能な連続焼鈍炉は高価であり、生産量が多くない場合は導入が難しい。
【0009】
【発明が解決しようとする課題】
このような現状に鑑み、くり返し充放電によっても高性能が保たれるリチウムイオン二次電池を歩留まり・生産性よく製造するために、負極集電体として用いられる銅箔には、引張り強さが大きく、延性があり、導電率が高いというだけでなく、保管、電極製造工程及び使用時において軟化が起りにくいという特性がより強く求められるようになってきた。なお、電解銅箔は、引張り強さ320N/mm、耐力250N/mm、伸び12%を示し、130℃で30分加熱後も初期の機械的性質をほぼ維持でき、タフピッチ銅圧延箔と比べると耐熱性にも優れるが、価格が圧延銅箔より高価という問題がある。
また、前記(a)(c)の手段をとることなくバッチ炉で焼鈍しても、コイルの隣接する薄板間で密着が発生しない銅合金圧延箔が求められている。
【0010】
従って、本発明は、引張強さが大きく、延性があり、導電率が高く、さらに耐熱性に優れ、安価であり、かつバッチ炉で焼鈍しても密着の発生しない銅合金圧延箔を得ることを目的とする。
【0011】
【課題を解決するための手段】
本発明に係る圧延銅合金箔は、Co、Ni及びFeより選択した1種又は2種以上を総量で0.005〜0.05%、P:0.005〜0.025%とB:0.0001〜0.025%の1種又は2種を総量で0.005%〜0.025%以下含有し、さらにZn:0.005〜0.1%、Ti:0.005〜0.06%の1種又は2種を総量で0.005%〜0.1%含有し、残部Cu及び不可避不純物からなる。この圧延銅合金箔の特に望ましい組成は、前記組成においてCo、Ni及びFeのなかからCo:0.005〜0.05%を選択し、かつCoとPの総量を0.02%を越え0.06%以下、S:0.001%以下とした組成である。また、上記圧延銅合金箔は、さらにAg:0.005〜0.15%を含有することができる。
【0012】
上記圧延銅合金箔は、製品の箔厚さの150〜400%の厚さにおいて焼鈍を行い、次いで製品箔の厚さの103%以下の厚さまで冷間圧延後さらに焼鈍を行い、その後仕上げ圧延又は/及び張力を加えた平坦化処理を行って製造することができる。これにより、引張強さ300N/mm、伸び8%以上、導電率85%IACS以上、かつ130℃で30分〜2時間加熱後においても、その機械的特性をほぼ維持できるようになる。
【0013】
【発明の実施の形態】
次に、本発明に係る圧延銅合金箔の組成の限定理由を説明する。
(Co、Ni、Fe)
これらの元素は銅マトリクスに固溶し、あるいはPと金属間化合物を生成して析出し、圧延銅合金箔の引張強さ及び耐熱性を向上させる。しかし、これらの元素の含有量が0.005%未満の場合は、目標とする引張強さ及び耐熱性が得られず、0.05%を越えて含有されると導電率が低下する。従って、これらの元素の含有量は、1種又は2種以上を総量で0.005〜0.05%とする。
これらの元素をPと共添するとき、Pとの合計量を0.02%を越え0.06%以下の範囲とするのが望ましい。その下限は強度及び耐熱性、上限は導電率をそれぞれ安定的に確保するためである。
なお、Coは正極側活物質(LiCoO )に含まれる元素であり、銅箔から活物質に溶け出しても悪影響を与えないことから、強化の主体としてCoを用いることが望ましい。
【0014】
(P)
Pは脱酸作用があり、鋳造前に溶湯中に投入され溶湯中に吸収された酸素を除去するとともに、Co、Ni、Feとともに金属間化合物を形成して強度及び耐熱性を向上させる。しかし、鋳塊中に含まれる残存Pが0.005%未満の場合は、脱酸不足でOが0.002%を越えることがあり、その場合、Co、Ni、Feが酸化物を形成し、これらの元素による強化作用が失われる。Pが0.025%を越えて含まれると、固溶するCo、Ni、Feとともに導電率を低下させ、目標とする導電率が得られなくなる。従って、Pの含有量は0.005〜0.025%とする。
なお、Bも脱酸作用を有するが、PはCo、Ni、Feと金属間化合物を形成すること、電解質がLiPF を主成分とすること、及び脱酸不足を防止するために、P単独又はPとBの共添が望ましい。
【0015】
(B)
Bは微量含有した場合でも、溶湯中の酸素を除去して溶湯を清浄化し、溶湯の流動性を向上させることによって鋳造性を向上させる。通常はPとともに添加される。BはPに比べて圧延銅合金箔の導電率を低下させず、また熱延工程及び熱処理工程において板表面の内部酸化を防止し、箔の表面品質を向上させ、Liイオン二次電池の電極活物質の密着性を向上させる。0.0001%という微量の添加で上記効果が得られるが、0.025%を越えると導電率が低下するため、Bの含有量は0.0001〜0.025%とする。
PとBはそれぞれ単独又は共添され、その含有量は、P:0.005〜0.025%、B:0.0001〜0.025%を総量で0.005〜0.025%の範囲内とする。
【0016】
(Zn、Ti)
Zn及びTiは、それぞれ微量でも単独又は共に存在することによって、銅合金圧延箔又はその箔地をコイルで焼鈍する場合において、焼付きによる密着を防止する効果を有する。これらの元素の1種又は2種の含有量が0.005%未満では前記の効果が十分でない。Znの含有量が0.1%を越えると、イオン化して電極活物質を汚染させ、電池の性能を低下させるおそれがあるため、その上限値を0.1%とする。Tiの含有量が0.06%を超えると、溶解鋳造時に発生するTiの酸化物の量が増加して鋳造性が低下するため、鋳塊の歩留りが低下する。また、銅箔製造工程中の熱処理工程において、板材表面に形成されるTiの酸化膜が通常の酸洗で除去しにくいため、生産性が低下しやすくなる。従って、Zn:0.005〜0.1%、Ti:0.005〜0.06%の1種又は2種の含有量は総量で0.005%以上0.1%以下とする。望ましくは、Zn:0.01〜0.08%、Ti:0.01〜0.05%の1種又は2種の含有量が総量で0.01〜0.08%である。
【0017】
(Ag)
Agは導電率をほとんど低下させることなく、銅合金圧延箔の強度と耐熱性を向上させるため、必要に応じて添加する。しかし、Agの含有量が0.005%未満ではその効果が小さく、0.25%を越えて含有させると価格上昇が大きくなるため、その含有量を0.005〜0.25%とする。
【0018】
(不純物元素)
(S)
Sは地金、原料、炉材、酸化防止の木炭及びフラックス等から必然的に混入する。Sが0.001%を越えて含まれると、主としてCuS又はCuSとなるが、このSはフリーとなりやすく、粒界及び欠陥部に偏析する。この場合には、特に箔状態では伸びが低下したり、応力付加時に切断しやすくなる。従って、Sの含有量は0.001%以下とする。
Sの除去は、溶湯の組成を調整後、P又は/及びBで脱酸し、直にMgあるいはCaを添加して硫化物を形成させ、浮上した硫化物を他のスラグとともに除去することで対応できる。
【0019】
(酸素、水素)
本発明に係る銅合金圧延箔においては、酸素含有量を0.003%未満とすることが望ましい。酸素含有量が0.003%以上になると、箔中に存在する酸化物の界面で割れが発生して箔の展伸性低下や切れが起こり易くなり、また、その界面において回復・再結晶が起こり、本発明の目的とする耐熱性が得られなくなるためである。
また、水素含有量は0.0002%未満とすることが望ましい。水素含有量が0.0002%以上になると、箔の加工熱処理工程において膨れ、表面クラック、はがれなどの欠陥となり、箔の歩留り・生産性を悪くする。また、リチウム二次電池の集電体として電池に組込まれた後も充電時の温度上昇などによって水素が粒界に移動して粒界強度を低下させ、その結果電池寿命を低下させてしまう。このような理由から、水素の含有量は0.0002%以下であることが望ましく、0.0001%以下であることが更に望ましい。水素含有量を0.0002%未満とするには、使用原料の乾燥、溶解鋳造工程における炉材、鋳型の十分な乾燥、雰囲気制御、脱ガス処理(Arガスバブリング)などが重要である。
【0020】
(他の不純物)
本発明に係る銅合金圧延箔における不可避的不純物元素は、原料あるいは溶解鋳造工程において不可避的にCuに含有される元素であり、前記S、O、H以外では、Li、Be、Al、Mg、Si、Cr、Mn、As、Se、Zr、Cd、In、Sn、Sb、Te、Au、Pbなどである。本発明の銅合金箔においては、マトリックスに固溶、晶出、析出又は酸化物として存在しているこれら他の不純物元素の含有量が合計で0.02%以下であれば、本発明に係る銅合金圧延箔において強度、耐熱性などに影響を及ぼさない。ただし、Si、As、Sbなどの元素は微量でも導電率を低下させるので、導電率を高く保つにはこれらの元素はそれぞれ0.005%未満、計0.01%未満とすることが必要である。また、Mg、Al、Mn、Crなどの元素は焼鈍時に焼付きを発生させやすくするため、合計で0.01%未満とすることが望ましい。
【0021】
次に、本発明に係る圧延銅合金箔の製造方法について説明する。
(溶解鋳造)
本発明に係る銅合金圧延箔を製造するための鋳塊は、電気銅、無酸素銅及びこれらのスクラップを銅の溶解原料とすることができる。AgはCuより低融点であり、Ag地金を用いても、Cu−Ag中間合金を用いてもよい。B及びPの添加には、添加歩留りをよくするためにCu−2%B、Cu−15%Pなどの中間合金を用いるとよい。Co、Ni、Feは、その地金を用いてもよいし、これらの元素とCuとの中間合金を用いてもよい。
【0022】
本発明に係る銅合金圧延箔において、酸素の含有量を0.003%以下とする場合には、無酸素銅の溶解方法(CO−CO混合雰囲気にて溶解鋳造、真空溶解など)の適用、あるいはシャフト炉、電気保持炉、コアレス炉などを用いる通常の溶解鋳造設備において、溶湯の脱酸処理後、溶解炉、樋、鋳型の溶湯表面をフラックス、黒鉛粒子、木炭、不活性ガスなどでカバーすることによって可能である。なお、溶湯の脱酸のためにはCu−2%B、Cu−15%Pなどを、脱硫にはMg、Cu−Mg中間合金、Ca、Cu−Ca中間合金などを適宜用いればよい。
水素の含有量を0.0002%以下とするには、溶解原料、炉、樋、鋳型などの乾燥、雰囲気の露点管理などによって可能である。水素の分析は例えば、鋳塊よりサンプルを採取し、JIS−Z2614に規定の方法で行うとよい。
鋳造においては、通常の竪型連続鋳造、横形連続鋳造、薄スラブ連続鋳造などの連続鋳造、及びダービル鋳造、金型鋳造などの鋳造方法を適用して造塊が可能である。
【0023】
(箔地の加工熱処理)
上述の方法で造塊された本発明に係る圧延銅合金箔用の鋳塊は、熱間圧延性、冷間圧延性共に良好であり、竪型連続鋳造、ダービル鋳造などの方法で製造された鋳塊を熱延し、その後冷延と熱処理を組合せて箔地とすることも、横形連続鋳造、薄スラブ連続鋳造などの方法で製造された鋳塊(厚さ数mm〜30mm程度)を冷延と熱処理を組合せて箔地とすることも可能である。
例えば、鋳塊を700〜950℃で加熱後、熱間圧延を行って厚さ15〜25mmとした後、冷間圧延と焼鈍を組合せて所定の厚さの圧延箔地とする。冷延途中、厚さ0.5〜1.5mm、又は/及び0.15〜0.3mm程度で焼鈍を行った後、製品の箔厚さの150〜400%の厚さになるまで冷間圧延を行う。
【0024】
(箔の加工熱処理)
本発明に係る銅合金箔は、(1)製品の箔厚さの150〜400%の厚さにおいて焼鈍→(2)製品箔の厚さの103%以下の厚さまで冷間圧延→(3)焼鈍後製品箔の厚さまで仕上げ圧延、(3’)焼鈍後製品箔の厚さまで冷間圧延後張力を加えた平坦化処理、又は(3”)焼鈍後張力を加えた平坦化処理(この場合は、(2)の工程で製品箔の厚さまで冷間圧延することになる)、の工程により製造される。なお、(1)のように箔地が製品箔厚の数倍になった時点で中間焼鈍すること自体は、特開平10−230303号公報に記載されているように公知である。
【0025】
(1)において、焼鈍を行う厚さが製品箔の厚さの400%を越えると、その後の冷延加工率が大きくなるため、最終焼鈍((3)(3’)、(3”))における軟化が激しく、目的とする引張強さと伸びの良好な組み合せを達成できない。また、焼鈍を行う厚さが150%未満であると、その後の冷延加工率が小さくなるため冷延後の引張強さが得られず、またその後最終焼鈍((3)(3’)、(3”))を行うと引張強さがさらに低下してしまう。従って、製品箔厚さの150〜400%の厚さにおいて焼鈍することが望ましい。この焼鈍は、銅合金箔地を軟化させることが目的であり、バッチ式の焼鈍炉を用いた焼鈍の例を挙げると、炉内の材料が250〜650℃になった後30分〜2時間程度保持すればよい。
【0026】
また、(2)及び(3)(3’)(3”))の工程は銅合金箔にバランスのよい引張強さ、伸び及び耐熱性の組み合せ、あるいはさらに良好な平坦性を持たすために必要な工程である。(2)の工程において冷延を製品箔の厚さの103%を越える厚さで終了すると、(3)又は(3’)の圧延により伸びの減少が大きくなる。従って、(2)の冷延は製品箔の厚さの103%以下の厚さまで行うことが望ましい。(3)(3’)、(3”)における焼鈍は材料が半軟化する焼鈍とすることが望ましい。この半軟化焼鈍により、冷間圧延で本発明銅合金に導入された転位は、熱運動によって消滅しやすいものから消滅し、転位の再配列が起こるため延性が回復し、転位組織の安定化が達成される。
なお、この半軟化とは、焼鈍前の材料の硬さ(箔の場合、ヌープ硬さ)をH1、材料が完全に再結晶(例えば400〜600℃×2時間加熱)したときの硬さをH、ΔH=H1−Hとしたとき、材料の焼鈍後の硬さがおよそH=H+0.5×ΔHとなる状態である。バッチ式の焼鈍炉を用いた場合、例えば炉内の材料が150〜400℃になった後、30分〜2時間程度保持すればよい。
【0027】
【実施例】
以下に本発明を実施例に基づいて説明するが、本発明がこの実施例に限定されるものではない。
(実施例1)
木炭被覆下において、電気銅(純度99.95%以上)を溶解し、Agショット(純度99.99%以上)、Zn、Cu−50%Co、Cu−30%Ni、Cu−10%Fe、Cu−15%P、Cu−2%B、Cu−15%Tiなどの金属や中間合金を原料として、表1に示す組成の銅合金鋳塊(幅60mm、厚さ60mm、長さ200mm)を金型に鋳造した。また、比較例13として、タフピッチ銅連鋳塊より直方体のブロックを切り出し、旋盤加工によって前記の寸法とした。なお、比較例No.10は溶湯脱酸後のCa及びMg添加による脱硫を行っていない。
表1に示した組成は、銅箔とした後の測定値である。各元素の含有量は、JISに規定の方法、ICP−MS、GD−MS、原子吸光法などの方法によって、酸素含有量は不活性ガス融解赤外線吸収法(JISH1067)によって、水素含有量はJISZ2614によって行った。
【0028】
【表1】

Figure 0004743977
【0029】
No.1〜12の鋳塊は以下の工程により、厚さ0.015mmの箔に加工した。(1)800℃で1時間加熱後熱延(60mmt→15mmt)、(2)冷延(→1.0mmt)、(3)500℃のソルトバス中で20秒間加熱焼鈍、(4)酸洗後冷延(→0.2mmt)、(5)500℃のソルトバス中で20秒間加熱焼鈍、(6)酸洗後冷延(→0.055mmt)、(7)不活性ガス中、400℃で2時間加熱焼鈍、(8)酸洗後冷延(→0.0151mmt)、(9)不活性ガス中、300〜400℃で2時間加熱し焼鈍、(10)張力を加えながらスキンパス圧延(→0.0150mmt)。
なお、No.15のタフピッチ銅のみは、上記(5)、(7)、(9)の工程において、加熱温度をそれぞれ600℃、150℃、120℃とし、他の工程は同じとした。
【0030】
製造された各圧延箔より、引張方向が圧延方向に平行となるように、引張試験片(JIS5号、n=3)及び導電率の測定試験片(JISH0505、幅10mm、長さ300mm、n=2)を加工し、引張強さ、伸び及び導電率を測定した。これらの結果を表2に示す。なお、表2に示した最終焼鈍条件の温度は、先に定義した半軟化温度である。
また、密着性の試験は、前記(4)の0.2mmt圧延材より20mm×20mmの試験片を多数切出し、溶剤脱脂及び電解脱脂を行った後、図1に示すように、鋼製の保持板1間に試験片2を各2枚ずつ挟み、治具3のねじ摘みをトルクレンチで回して締め付け、室温で600Nの加圧力がかかるようにした。前記方法により加圧した試料を大量の粉末木炭を詰めた銅管に埋め込んで350℃に加熱し、試験片の温度が350℃に到達した後2時間保持した。2時間経過後、試験片の温度が50℃になるまで炉冷した。その後、加圧を解き、試験片の密着発生の有無を調査した。各組成毎に5組試験し、いずれかの試験片が一部でも密着している場合は、程度によらず密着ありと判断した。
【0031】
【表2】
Figure 0004743977
【0032】
表2に示すように、No.1〜7の銅合金箔は、引張り強さ、伸び及び導電率がいずれも目標とする値を満足する。また半軟化温度(最終焼鈍の温度)が高く、これは、銅合金箔への活物質形成工程におけるライン停止(130℃に保持)においても軟化せず、箔の伸び、箔の切れなどの問題が生じないことを意味する。
一方、No.8はCo含有量が少ないため、引張強さが目標値に達せず、No.9はCo含有量が多いため、導電率が低くなっている。No.10はS含有量が0.0018%と多いため、伸びが低い。No.11及びNo.12はNi、Feが過剰なため、導電率が低い。No.13及びNo.14は引張り強さ、伸び、導電率は本発明例No.13と同様良好な特性を有するが、Zn又は/及びTiの含有量が少ないため、焼鈍によって密着が発生した。タフピッチ銅のNo.15は伸びが小さく、かつ半軟化温度が120℃と低い。従って、ライン停止において130℃に保持されると軟化し、箔の伸び、箔の切れなどの問題が生じやすい。
【0033】
【発明の効果】
本発明に係る圧延銅合金圧延箔は、適切な製造工程を選定することにより、引張強さ300N/mm以上、伸び8%以上、導電率85%IACS以上の特性を備えることが可能であり、また、半軟化温度が高いので、例えば130℃で30分〜4時間加熱保持された程度では軟化せず、引張強さ300N/mm以上、伸び8%以上の特性を維持できる。また、コイルで焼鈍を行っても焼付きが発生しないため、コイルの密着が起こらず歩留まり及び生産性を高めることが可能となる。
従って、リチウムイオン二次電池などの負極集電体の製造工程における乾燥工程において軟化することが少なく、生産性の向上に大きく寄与し、かつ電池に組込まれた後の充電放電サイクルにおいても箔の切断、活物質の剥離などが起きにくく、リチウムイオン二次電池の高性能化、長寿命化にも大きく寄与する。
【図面の簡単な説明】
【図1】 密着性試験の方法を説明する模式図である。
【符号の説明】
1 保持板
2 試験片
3 治具[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a copper alloy rolled foil that can be used as a negative electrode side current collector electrode material such as a secondary battery, in particular, a lithium ion secondary battery or a polymer battery.
[0002]
[Prior art]
A negative electrode side current collector of a lithium ion secondary battery or a polymer battery is obtained by dissolving polyvinylidene fluoride (PVDF) in N-methylpyrrolidone on a tough pitch copper rolled foil or an electrolytic copper foil having a thickness of about 10 to 20 μm, A paste in which powdery graphite as a substance is mixed is applied by a # 60 bar coater to a thickness of about 90 μm and then dried at 130 ° C. for 3 minutes.
[0003]
The reason why tough pitch copper rolled foil or electrolytic copper foil is used as the negative electrode side current collector is that the thermal conductivity is large and heat generated during charging can be quickly removed, and a high strength can be obtained relatively easily. It depends on the ability to withstand the tensile stress applied to the copper foil in the active material application process and the drying process, and the ionization tendency. The negative electrode side current collector manufactured in this way is stacked with a positive electrode side current collector (a positive electrode active material is applied to an aluminum foil) via a separator, and is integrated by a press and wound (for details) (Omitted).
[0004]
By the way, the following problems have been pointed out in tough pitch copper.
(1) Heat-resistant tough pitch copper has high thermal conductivity (conductivity of 98% IACS or more), and by increasing the rolling reduction of cold rolling, tensile strength is 450 to 475 N / mm 2 , yield strength is 420 to 450 N / mm 2 , elongation A content of 0.4 to 2% can be obtained relatively easily. However, tough pitch copper contains oxygen and contains copper oxide and impurity element oxide particles in the copper foil, so that there are very few elements dissolved in the matrix, and cuprous oxide and impurity oxides. Since heat recovery and recrystallization are likely to occur at the interface, the heat resistance is considerably reduced compared to oxygen-free copper and phosphorus-deoxidized copper. For this reason, in the foil manufacturing process, even if high-strength tough pitch copper is manufactured, if it is stored at room temperature for a long time, recovery and recrystallization will occur, and phenomena such as a decrease in strength and an increase in elongation will occur. To do. Such a softening phenomenon is particularly remarkable in the spring-summer season when the temperature of the storage atmosphere is high.
[0005]
In the tough pitch copper rolled foil that has been softened in this way, since the tensile strength is reduced, it is necessary to change the tension applied to the foil in the application and drying steps of the active material according to the degree of softening. Therefore, work such as strength confirmation is newly generated in advance when applying to the coating process, which is very complicated. Further, when using a foil that is severely softened, the foil is easily cut or stretched in the above-described process, resulting in a decrease in productivity. Furthermore, if the tough pitch copper rolled foil softens over time due to heat generated by charging and discharging after being incorporated in the battery, the foil breaks due to the expansion and contraction of the active material, the active material peels off, and the battery performance deteriorates. End up.
Therefore, for example, in Japanese Patent Application Laid-Open No. 11-88673, by adding a small amount of Ag to copper, and in Japanese Patent Application Laid-Open No. 11-88672, by reducing the amount of oxygen contained in copper, both are stored at room temperature. It has been proposed to prevent softening by suppressing recovery and recrystallization.
[0006]
Even when using a tough pitch copper rolled foil that has not been softened during storage, softening is likely to occur due to heating (130 ° C.) in the drying step after application of the active material, and when the foil after drying is wound up, Elongation and foil breakage may occur, reducing yield and productivity. In addition, the active material application and drying processes are continuously performed while rewinding the coiled copper foil, but if the foil is cut or the line malfunctions during the manufacturing process, the line must be stopped. In such a case, the drying time of the applied active material may be 30 minutes or more. Due to a process trouble in the drying process, if the foil to be dried stays in the furnace for a long time, the softening becomes larger, and this part may not be used as a product.
In the case of a tough pitch copper rolled foil, the ductility of the foil may cause a breakage of the foil during the rolling process and the production of a lithium ion secondary battery, leading to a decrease in productivity and yield.
[0007]
(2) An annealing process exists in the manufacturing process of the adhesion tough pitch copper rolled foil at the time of annealing. The purpose of annealing is softening, and since tough pitch copper is not a precipitation-type alloy, a batch furnace or a continuous annealing furnace may be used for the annealing. However, if a coil with a thin plate is annealed in a batch furnace, the coil winding force may cause sticking between adjacent thin plates during annealing, resulting in an extremely low coil yield due to annealing. There was a problem.
[0008]
In order to prevent such adhesion, (a) reduce the annealing temperature of the coil, (b) reduce the coil tightening force, (c) apply adhesion prevention oil and anneal, (d) continuous There are methods such as annealing. However, there are the following problems. As for (a) , since the degree of softening is low, the number of annealing in the manufacturing process increases and the productivity is lowered. As for (b) , since the coil is loosely wound, the thin plate is rubbed during coil transportation. As a result, the yield is likely to decrease due to scratches. For (c) , the oxidized anti-adhesion oil is difficult to remove after annealing, so careful pickling and polishing is required. (D) is thin. A continuous annealing furnace capable of continuous annealing of foil and foil is expensive and difficult to introduce when the production volume is not large.
[0009]
[Problems to be solved by the invention]
In view of this situation, the copper foil used as the negative electrode current collector has a tensile strength in order to manufacture a lithium ion secondary battery that maintains high performance even by repeated charge and discharge with high yield and productivity. In addition to being large, ductile, and having high electrical conductivity, there has been a strong demand for characteristics such that softening is unlikely to occur during storage, electrode manufacturing processes, and use. The electrolytic copper foil has a tensile strength of 320 N / mm 2 , a proof stress of 250 N / mm 2 , and an elongation of 12%, and can substantially maintain the initial mechanical properties even after heating at 130 ° C. for 30 minutes. Compared with heat resistance, the price is higher than that of rolled copper foil.
Further, there is a demand for a copper alloy rolled foil that does not cause adhesion between adjacent thin plates of a coil even if annealing is performed in a batch furnace without taking the above-described means (a) to (c) .
[0010]
Accordingly, the present invention provides a copper alloy rolled foil having high tensile strength, ductility, high electrical conductivity, excellent heat resistance, low cost, and no adhesion even when annealed in a batch furnace. With the goal.
[0011]
[Means for Solving the Problems]
The rolled copper alloy foil according to the present invention comprises one or more selected from Co, Ni and Fe in a total amount of 0.005 to 0.05%, P: 0.005 to 0.025% and B: 0. One or two of 0.0001 to 0.025% is contained in a total amount of 0.005% to 0.025% or less, and Zn: 0.005 to 0.1%, Ti: 0.005 to 0.06 1 type or 2 type% is contained in a total amount of 0.005% to 0.1%, and consists of the balance Cu and inevitable impurities. A particularly desirable composition of this rolled copper alloy foil is that Co: 0.005 to 0.05% is selected from Co, Ni and Fe in the above composition, and the total amount of Co and P exceeds 0.02% and is 0. 0.06% or less and S: 0.001% or less. The rolled copper alloy foil may further contain Ag: 0.005 to 0.15%.
[0012]
The rolled copper alloy foil is annealed at a thickness of 150 to 400% of the product foil thickness, then cold-rolled to a thickness of 103% or less of the product foil thickness, and further annealed, and then finish rolled. Or it can manufacture by performing the planarization process which added tension. As a result, the tensile strength is 300 N / mm 2 , the elongation is 8% or more, the conductivity is 85% IACS or more, and the mechanical properties can be substantially maintained even after heating at 130 ° C. for 30 minutes to 2 hours.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, the reason for limiting the composition of the rolled copper alloy foil according to the present invention will be described.
(Co, Ni, Fe)
These elements are dissolved in the copper matrix, or generate and precipitate P and an intermetallic compound, thereby improving the tensile strength and heat resistance of the rolled copper alloy foil. However, when the content of these elements is less than 0.005%, the target tensile strength and heat resistance cannot be obtained, and when the content exceeds 0.05%, the conductivity decreases. Accordingly, the total content of these elements is 0.005 to 0.05%.
When these elements are co-added with P, the total amount of P is preferably in the range of more than 0.02% and not more than 0.06%. The lower limit is for ensuring strength and heat resistance, and the upper limit is for ensuring stable conductivity.
Note that Co is an element contained in the positive electrode side active material ( LiCoO 2 ), and since it does not have an adverse effect even if it is dissolved from the copper foil into the active material, it is desirable to use Co as a main body for strengthening.
[0014]
(P)
P has a deoxidizing action, removes oxygen absorbed in the molten metal before being cast, and forms intermetallic compounds with Co, Ni, and Fe to improve strength and heat resistance. However, when the residual P contained in the ingot is less than 0.005%, O may exceed 0.002% due to insufficient deoxidation. In this case, Co, Ni, and Fe form oxides. , The strengthening action by these elements is lost. When P exceeds 0.025%, the electrical conductivity is lowered together with solid solution of Co, Ni, and Fe, and the target electrical conductivity cannot be obtained. Therefore, the content of P is set to 0.005 to 0.025%.
Note that B also has a deoxidation effect, but P forms an intermetallic compound with Co, Ni, Fe, the electrolyte is mainly composed of LiPF 6 , and P is used alone to prevent deoxidation shortage. Or co-addition of P and B is desirable.
[0015]
(B)
Even when a small amount of B is contained, the castability is improved by removing oxygen in the molten metal to purify the molten metal and improving the fluidity of the molten metal. Usually added with P. B does not lower the conductivity of the rolled copper alloy foil compared to P, prevents internal oxidation of the plate surface in the hot rolling process and the heat treatment process, improves the surface quality of the foil, and the electrode of the Li ion secondary battery Improve the adhesion of the active material. The above effect can be obtained by adding a small amount of 0.0001%. However, if the content exceeds 0.025%, the conductivity decreases, so the B content is set to 0.0001 to 0.025%.
P and B are each independently or co-added, and the content thereof is in the range of 0.005 to 0.025% in total of P: 0.005 to 0.025% and B: 0.0001 to 0.025%. Within.
[0016]
(Zn, Ti)
Zn and Ti have the effect of preventing adhesion due to seizure when copper alloy rolled foil or its foil is annealed with a coil by being present alone or together even in a small amount. If the content of one or two of these elements is less than 0.005%, the above effects are not sufficient. If the Zn content exceeds 0.1%, the ion active material may be contaminated and the performance of the battery may be lowered. Therefore, the upper limit is set to 0.1%. When the Ti content exceeds 0.06%, the amount of Ti oxide generated during melt casting increases and castability deteriorates, so the yield of the ingot decreases. Further, in the heat treatment step in the copper foil manufacturing step, the Ti oxide film formed on the surface of the plate material is difficult to remove by normal pickling, and thus the productivity is likely to be lowered. Therefore, the content of one or two of Zn: 0.005 to 0.1% and Ti: 0.005 to 0.06% is 0.005% or more and 0.1% or less in total. Desirably, the content of one or two of Zn: 0.01 to 0.08% and Ti: 0.01 to 0.05% is 0.01 to 0.08% in total.
[0017]
(Ag)
Ag is added as necessary in order to improve the strength and heat resistance of the copper alloy rolled foil with almost no decrease in conductivity. However, if the content of Ag is less than 0.005%, the effect is small, and if the content exceeds 0.25%, the price increases, so the content is made 0.005 to 0.25%.
[0018]
(Impurity element)
(S)
S is inevitably mixed in from metal, raw materials, furnace materials, antioxidant charcoal and flux. When S exceeds 0.001%, it is mainly CuS or Cu 2 S, but this S tends to be free and segregates at grain boundaries and defect portions. In this case, particularly in the foil state, the elongation is reduced, and it becomes easy to cut when stress is applied. Therefore, the S content is 0.001% or less.
S is removed by adjusting the composition of the molten metal, deoxidizing with P or / and B, adding Mg or Ca directly to form a sulfide, and removing the floating sulfide together with other slag. Yes.
[0019]
(Oxygen, hydrogen)
In the copper alloy rolled foil according to the present invention, the oxygen content is preferably less than 0.003%. When the oxygen content is 0.003% or more, cracking occurs at the interface of the oxides present in the foil, and the stretchability of the foil is likely to decrease or break, and recovery / recrystallization occurs at the interface. This is because the heat resistance aimed at by the present invention cannot be obtained.
The hydrogen content is preferably less than 0.0002%. When the hydrogen content is 0.0002% or more, the foil is swelled in the heat treatment process of the foil, resulting in defects such as surface cracks and peeling, which deteriorates the yield and productivity of the foil. In addition, even after being incorporated in a battery as a current collector of a lithium secondary battery, hydrogen moves to the grain boundary due to a temperature rise during charging and the like, reducing the grain boundary strength, and as a result, reducing the battery life. For these reasons, the hydrogen content is preferably 0.0002% or less, and more preferably 0.0001% or less. In order to make the hydrogen content less than 0.0002%, it is important to dry the raw materials used, furnace materials in the casting process, sufficient drying of the mold, atmosphere control, degassing (Ar gas bubbling), and the like.
[0020]
(Other impurities)
The inevitable impurity element in the copper alloy rolled foil according to the present invention is an element inevitably contained in Cu in the raw material or the melt casting process. Except for S, O, and H, Li, Be, Al, Mg, Si, Cr, Mn, As, Se, Zr, Cd, In, Sn, Sb, Te, Au, Pb, and the like. In the copper alloy foil of the present invention, if the total content of these other impurity elements existing as solid solution, crystallization, precipitation or oxide in the matrix is 0.02% or less, the present invention is concerned. Does not affect strength, heat resistance, etc. in copper alloy rolled foil. However, since elements such as Si, As, and Sb decrease the conductivity even in a small amount, these elements need to be less than 0.005% and less than 0.01% in total in order to keep the conductivity high. is there. In addition, elements such as Mg, Al, Mn, and Cr are desirably less than 0.01% in total in order to easily cause seizure during annealing.
[0021]
Next, the manufacturing method of the rolled copper alloy foil which concerns on this invention is demonstrated.
(Melting casting)
The ingot for producing the copper alloy rolled foil according to the present invention can use electrolytic copper, oxygen-free copper and scraps thereof as a melting material for copper. Ag has a lower melting point than Cu, and either an Ag ingot or a Cu—Ag intermediate alloy may be used. For the addition of B and P, an intermediate alloy such as Cu-2% B or Cu-15% P is preferably used in order to improve the addition yield. As for Co, Ni, and Fe, a bare metal may be used, or an intermediate alloy of these elements and Cu may be used.
[0022]
In the copper alloy rolled foil according to the present invention, when the content of oxygen and 0.003% or less, application of the method of dissolving oxygen-free copper (molten and cast in CO-CO 2 mixed atmosphere, such as vacuum melting) Or, in ordinary melting and casting equipment using a shaft furnace, electric holding furnace, coreless furnace, etc., after deoxidation of the molten metal, the molten furnace, iron, and molten metal surface of the mold are treated with flux, graphite particles, charcoal, inert gas, etc. It is possible by covering. In addition, Cu-2% B, Cu-15% P or the like may be used as appropriate for deoxidation of the molten metal, and Mg, Cu—Mg intermediate alloy, Ca, Cu—Ca intermediate alloy, or the like may be used as appropriate for desulfurization.
In order to make the hydrogen content 0.0002% or less, it is possible to dry the melting raw material, furnace, firewood, mold, etc., and control the dew point of the atmosphere. For example, the analysis of hydrogen may be performed by taking a sample from an ingot and performing a method defined in JIS-Z2614.
In casting, it is possible to ingot by applying casting methods such as ordinary vertical continuous casting, horizontal continuous casting, thin slab continuous casting, and darbil casting, die casting.
[0023]
(Processing heat treatment of foil)
The ingot for the rolled copper alloy foil according to the present invention formed by the above-described method has good hot rolling properties and cold rolling properties, and was manufactured by a method such as vertical casting and darbil casting. The ingot can be hot-rolled and then combined with cold rolling and heat treatment to form a foil, or an ingot (thickness of about several mm to 30 mm) manufactured by a method such as horizontal continuous casting or thin slab continuous casting can be cooled. It is also possible to use foil and heat treatment in combination.
For example, the ingot is heated at 700 to 950 ° C., hot rolled to a thickness of 15 to 25 mm, and then cold rolled and annealed to obtain a rolled foil having a predetermined thickness. In the middle of cold rolling, after annealing at a thickness of about 0.5 to 1.5 mm or / and about 0.15 to 0.3 mm, it is cold until it becomes a thickness of 150 to 400% of the foil thickness of the product Roll.
[0024]
(Processing heat treatment of foil)
The copper alloy foil according to the present invention comprises: (1) annealing at a thickness of 150 to 400% of the product foil thickness → (2) cold rolling to a thickness of 103% or less of the product foil thickness → (3) Finishing and rolling to the thickness of the product foil after annealing, (3 ') Planarization treatment with the tension after cold rolling to the thickness of the product foil after annealing, or (3 ") Planarization treatment with the tension after annealing (in this case) Is cold-rolled to the thickness of the product foil in the step (2) ), when the foil becomes several times the product foil thickness as in (1) . Intermediate annealing itself is known as described in JP-A-10-230303.
[0025]
In (1) , if the thickness of annealing exceeds 400% of the thickness of the product foil, the subsequent cold rolling rate increases, so final annealing ( (3) , (3 '), (3 ") In addition, the desired combination of tensile strength and elongation cannot be achieved, and if the thickness to be annealed is less than 150%, the subsequent cold-rolling rate decreases, so If the tensile strength cannot be obtained and the final annealing ( (3) , (3 ′), (3 ″) ) is performed thereafter, the tensile strength is further reduced. Therefore, it is desirable to anneal at a thickness of 150 to 400% of the product foil thickness. The purpose of this annealing is to soften the copper alloy foil, and an example of annealing using a batch-type annealing furnace is 30 minutes to 2 hours after the material in the furnace reaches 250 to 650 ° C. It is sufficient to hold the degree.
[0026]
In addition, the steps (2) and (3) ( (3 ') , (3 ") ) have a balanced combination of tensile strength, elongation and heat resistance, or better flatness on the copper alloy foil. When the cold rolling is finished at a thickness exceeding 103% of the thickness of the product foil in the step (2) , the reduction in elongation becomes large due to the rolling of (3) or (3 ′) . Therefore, it is desirable to perform the cold rolling of (2) up to a thickness of 103% or less of the thickness of the product foil. (3 ) The annealing in (3 ′) and (3 ″) is an annealing in which the material is semi-softened. It is desirable. Due to this semi-softening annealing, dislocations introduced into the copper alloy of the present invention by cold rolling disappear from the ones that easily disappear due to thermal motion, and the rearrangement of the dislocations occurs, so that the ductility is restored and the dislocation structure is stabilized. Achieved.
This semi-softening means that the hardness of the material before annealing (Knoop hardness in the case of foil) is H1, and the hardness when the material is completely recrystallized (for example, heated at 400 to 600 ° C. for 2 hours). H 0, when the ΔH = H1-H 0, hardness after annealing of the material is in the condition to be approximately H = H 0 + 0.5 × ΔH . When a batch-type annealing furnace is used, for example, after the material in the furnace reaches 150 to 400 ° C., it may be held for about 30 minutes to 2 hours.
[0027]
【Example】
The present invention will be described below based on examples, but the present invention is not limited to these examples.
Example 1
Under the charcoal coating, electrolytic copper (purity 99.95% or more) is dissolved, Ag shot (purity 99.99% or more), Zn, Cu-50% Co, Cu-30% Ni, Cu-10% Fe, A copper alloy ingot (width 60 mm, thickness 60 mm, length 200 mm) having the composition shown in Table 1 is made from a metal such as Cu-15% P, Cu-2% B, Cu-15% Ti, or an intermediate alloy. Cast into mold. Further, as Comparative Example 13, a rectangular parallelepiped block was cut out from a tough pitch copper continuous ingot, and the above dimensions were obtained by lathe processing. Comparative Example No. No. 10 does not perform desulfurization by adding Ca and Mg after molten metal deoxidation.
The composition shown in Table 1 is a measured value after making a copper foil. The content of each element is determined by a method defined in JIS, such as ICP-MS, GD-MS, or atomic absorption method, the oxygen content is determined by an inert gas melting infrared absorption method (JIS 1067), and the hydrogen content is determined according to JIS Z2614. Went by.
[0028]
[Table 1]
Figure 0004743977
[0029]
No. The ingots 1 to 12 were processed into foils having a thickness of 0.015 mm by the following steps. (1) Hot rolled at 800 ° C. for 1 hour and then hot rolled (60 mmt → 15 mmt), (2) Cold rolled (→ 1.0 mmt), (3) Heat annealed in a 500 ° C. salt bath for 20 seconds, (4) Pickling Post-cold rolling (→ 0.2 mmt), (5) Heat annealing in a salt bath at 500 ° C. for 20 seconds, (6) Cold-rolling after pickling (→ 0.055 mmt), (7) 400 ° C. in inert gas (8) Cold rolling after pickling (→ 0.0151 mmt), (9) Annealing in an inert gas at 300 to 400 ° C. for 2 hours, (10) Skin pass rolling while applying tension ( → 0.0150 mmt).
In addition, No. Only for 15 tough pitch copper, the heating temperatures were set to 600 ° C., 150 ° C. and 120 ° C. in the steps (5), (7) and (9), respectively, and the other steps were the same.
[0030]
From each of the manufactured rolled foils, a tensile test piece (JIS No. 5, n = 3) and a measurement specimen for electrical conductivity (JIS 0505, width 10 mm, length 300 mm, n = so that the tensile direction is parallel to the rolling direction. 2) was processed and the tensile strength, elongation and electrical conductivity were measured. These results are shown in Table 2. In addition, the temperature of the last annealing conditions shown in Table 2 is the semi-softening temperature defined previously.
Further, in the adhesion test, a large number of 20 mm × 20 mm test pieces were cut out from the 0.2 mm t rolled material of (4) above, and after performing solvent degreasing and electrolytic degreasing, as shown in FIG. Two test pieces 2 were sandwiched between the plates 1, and the screw knob of the jig 3 was tightened with a torque wrench so that a pressure of 600 N was applied at room temperature. The sample pressurized by the above method was embedded in a copper tube filled with a large amount of powdered charcoal and heated to 350 ° C., and held for 2 hours after the temperature of the test piece reached 350 ° C. After 2 hours, the furnace was cooled until the temperature of the test piece reached 50 ° C. Thereafter, the pressure was released and the presence or absence of adhesion of the test piece was investigated. Five sets were tested for each composition, and when any one of the test pieces was in close contact, it was determined that there was close contact regardless of the degree.
[0031]
[Table 2]
Figure 0004743977
[0032]
As shown in Table 2, no. The copper alloy foils 1 to 7 satisfy the target values for tensile strength, elongation, and conductivity. In addition, the semi-softening temperature (final annealing temperature) is high, and this does not soften even when the line is stopped (maintained at 130 ° C.) in the active material forming process on the copper alloy foil, and the foil stretches and the foil breaks. Does not occur.
On the other hand, no. No. 8 has a low Co content, so the tensile strength does not reach the target value. 9 has a low Co conductivity because of its high Co content. No. No. 10 has a low S content, so the elongation is low. No. 11 and no. No. 12 has a low electrical conductivity because of excessive Ni and Fe. No. 13 and no. No. 14 shows tensile strength, elongation, and electrical conductivity. Although it has the same favorable characteristics as 13, since the content of Zn or / and Ti is small, adhesion occurred by annealing. No. for tough pitch copper. No. 15 has a small elongation and a semi-softening temperature as low as 120 ° C. Therefore, when the temperature is maintained at 130 ° C. when the line is stopped, the film is softened, and problems such as foil elongation and foil breakage are likely to occur.
[0033]
【The invention's effect】
The rolled copper alloy rolled foil according to the present invention can be provided with characteristics such as a tensile strength of 300 N / mm 2 or more, an elongation of 8% or more, and a conductivity of 85% IACS or more by selecting an appropriate manufacturing process. Moreover, since the semi-softening temperature is high, for example, it is not softened when heated and maintained at 130 ° C. for 30 minutes to 4 hours, and the tensile strength of 300 N / mm 2 or more and the elongation of 8% or more can be maintained. In addition, since the seizure does not occur even if the coil is annealed, the coil does not adhere to each other, and the yield and productivity can be improved.
Therefore, it is less likely to soften in the drying process in the manufacturing process of the negative electrode current collector such as a lithium ion secondary battery, greatly contributes to the improvement of productivity, and also in the charge / discharge cycle after being incorporated in the battery. Cutting and peeling of the active material are unlikely to occur, greatly contributing to the high performance and long life of lithium ion secondary batteries.
[Brief description of the drawings]
FIG. 1 is a schematic diagram for explaining a method of an adhesion test.
[Explanation of symbols]
1 Holding plate 2 Test piece 3 Jig

Claims (4)

Co、Ni及びFeより選択した1種又は2種以上を総量で0.005〜0.05%(質量%、以下同じ)、P:0.005〜0.025%とB:0.0001〜0.025%の1種又は2種を総量で0.005%〜0.025%以下含有し、さらにZn:0.005〜0.1%、Ti:0.005〜0.06%の1種又は2種を総量で0.005%〜0.1%含有し、かつCo、Ni及びFeより選択した1種又は2種以上とPの総量が0.02%を越え0.06%以下、S:0.001%以下、残部Cu及び不可避不純物からなる圧延銅合金箔。One or more selected from Co, Ni and Fe in a total amount of 0.005 to 0.05% (mass%, the same applies hereinafter), P: 0.005 to 0.025% and B: 0.0001 to One or two of 0.025% is contained in a total amount of 0.005% to 0.025% or less, and Zn: 0.005 to 0.1%, Ti: 0.005 to 0.06% 1 The total amount of seeds or two kinds is 0.005% to 0.1%, and one or more kinds selected from Co, Ni and Fe and the total amount of P is more than 0.02% and not more than 0.06% , S: 0.001% or less, rolled copper alloy foil comprising the balance Cu and inevitable impurities. Co:0.005〜0.05%、P:0.005〜0.025%とB:0.0001〜0.025%の1種又は2種を総量で0.005%〜0.025%以下含有し、さらにZn:0.005〜0.1%、Ti:0.005〜0.06%の1種又は2種を総量で0.005%〜0.1%含有し、かつCoとPの総量が0.02%を越え0.06%以下、S:0.001%以下、残部Cu及び不可避不純物からなる圧延銅合金箔。  Co: 0.005 to 0.05%, P: 0.005 to 0.025%, and B: 0.0001 to 0.025%, or a total of 0.005% to 0.025% In addition, Zn: 0.005 to 0.1%, Ti: 0.005 to 0.06% of one or two of the total amount 0.005% to 0.1%, and Co and A rolled copper alloy foil in which the total amount of P exceeds 0.02% and is 0.06% or less, S: 0.001% or less, the remaining Cu and inevitable impurities. さらにAg:0.005〜0.15%を含有する請求項1又は2に記載された圧延銅合金箔。  Furthermore, the rolled copper alloy foil described in Claim 1 or 2 containing Ag: 0.005-0.15%. 箔製造工程において、製品の箔厚さの150〜400%の厚さにおいて焼鈍を行い、次いで製品箔の厚さの103%以下の厚さまで冷間圧延後さらに焼鈍を行い、その後仕上げ圧延又は/及び張力を加えた平坦化処理を行うことを特徴とする請求項1〜3のいずれかに記載された圧延銅合金箔の製造方法。  In the foil manufacturing process, annealing is performed at a thickness of 150 to 400% of the foil thickness of the product, then cold-rolled to a thickness of 103% or less of the thickness of the product foil, and further annealed, and then finish rolling or / The method for producing a rolled copper alloy foil according to any one of claims 1 to 3, wherein a flattening treatment is performed by applying tension and tension.
JP2001062814A 2001-03-07 2001-03-07 Rolled copper alloy foil and manufacturing method thereof Expired - Fee Related JP4743977B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001062814A JP4743977B2 (en) 2001-03-07 2001-03-07 Rolled copper alloy foil and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2001062814A JP4743977B2 (en) 2001-03-07 2001-03-07 Rolled copper alloy foil and manufacturing method thereof

Publications (2)

Publication Number Publication Date
JP2002266041A JP2002266041A (en) 2002-09-18
JP4743977B2 true JP4743977B2 (en) 2011-08-10

Family

ID=18921899

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2001062814A Expired - Fee Related JP4743977B2 (en) 2001-03-07 2001-03-07 Rolled copper alloy foil and manufacturing method thereof

Country Status (1)

Country Link
JP (1) JP4743977B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104711448A (en) * 2013-12-13 2015-06-17 北京有色金属研究总院 Copper alloy foil for power battery carrying fluid and processing method thereof

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MY158819A (en) * 2007-04-20 2016-11-15 Jx Nippon Mining & Metals Corp Electrolytic copper foil for lithium rechargeable battery and process for producing the copper foil
DE102007059443A1 (en) * 2007-12-10 2009-06-18 Li-Tec Vermögensverwaltungs GmbH Electrode for an energy storage
DE102008052985A1 (en) 2008-10-23 2010-04-29 Li-Tec Battery Gmbh Packaging device and packaging system for substantially flat objects, for example lithium-ion cells
DE102008053011A1 (en) 2008-10-23 2010-04-29 Li-Tec Battery Gmbh Galvanic cell for a rechargeable battery
DE102008053089A1 (en) 2008-10-24 2010-04-29 Li-Tec Battery Gmbh Accumulator with several galvanic cells
JP4992940B2 (en) * 2009-06-22 2012-08-08 日立電線株式会社 Rolled copper foil
WO2011108467A1 (en) * 2010-03-01 2011-09-09 古河電気工業株式会社 Surface treatment method for copper foil, surface treated copper foil and copper foil for negative electrode collector of lithium ion secondary battery
JP2012059778A (en) * 2010-09-06 2012-03-22 Jx Nippon Mining & Metals Corp Copper foil for printed wiring board
JP5490761B2 (en) * 2011-09-01 2014-05-14 Jx日鉱日石金属株式会社 Rolled copper foil for secondary battery negative electrode current collector, negative electrode material for lithium ion secondary battery and lithium ion secondary battery using the same
CN102876863B (en) * 2012-09-27 2014-05-07 山西春雷铜材有限责任公司 Heat treatment anti-sticking agent for copper foil strip
JP5718426B2 (en) * 2012-10-31 2015-05-13 古河電気工業株式会社 Copper foil, negative electrode for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery
JP2016132816A (en) * 2015-01-21 2016-07-25 三菱マテリアル株式会社 Copper alloy for electronic and electrical device, copper alloy thin sheet for electronic and electrical device and conductive component and terminal for electronic and electrical device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11339811A (en) * 1998-05-25 1999-12-10 Nippaku Sangyo Kk Copper alloy foil current collector for secondary battery
KR100346542B1 (en) * 1999-01-25 2002-07-26 삼성에스디아이 주식회사 Lithium secondary battery
JP2000328159A (en) * 1999-05-19 2000-11-28 Kobe Steel Ltd Copper alloy foil
JP2001011550A (en) * 1999-06-30 2001-01-16 Kobe Steel Ltd Copper alloy rolled foil

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104711448A (en) * 2013-12-13 2015-06-17 北京有色金属研究总院 Copper alloy foil for power battery carrying fluid and processing method thereof

Also Published As

Publication number Publication date
JP2002266041A (en) 2002-09-18

Similar Documents

Publication Publication Date Title
JP5856076B2 (en) Aluminum alloy foil for electrode current collector and method for producing the same
JP4743977B2 (en) Rolled copper alloy foil and manufacturing method thereof
KR101912767B1 (en) Aluminum alloy foil for electrode collector and production method therefor
JP4787986B2 (en) Copper alloy and manufacturing method thereof
JP5495649B2 (en) Aluminum alloy foil for lithium ion secondary battery and method for producing the same
JP2012224927A (en) Aluminum alloy foil for positive electrode current collector of lithium ion battery, and method for manufacturing the same
JP5448929B2 (en) Aluminum alloy hard foil having excellent bending resistance and method for producing the same
WO2012086447A1 (en) Aluminum alloy foil for electrode current collectors and manufacturing method thereof
JP2001152267A (en) Copper alloy rolled foil
WO2013176038A1 (en) Aluminum alloy foil for electrode collector, method for manufacturing same, and electrode material
JP2001011550A (en) Copper alloy rolled foil
JP5530865B2 (en) Aluminum alloy foil for lithium ion battery electrode material and electrode material using the same
JP3760668B2 (en) Secondary battery current collector
JP2001279351A (en) Rolled copper alloy foil and its production method
KR101944243B1 (en) Aluminum alloy foil for electrode collector and production method therefor
JP2012241232A (en) Rolled copper alloy foil and current collector for secondary battery using the same
JP6058915B2 (en) Rolled copper foil or rolled copper alloy foil for secondary battery negative electrode current collector, negative electrode material for lithium ion secondary battery and lithium ion secondary battery using the same
CN112170484B (en) Preparation method of copper-magnesium alloy strip for automobile relay
JP7042961B1 (en) Rolled copper foil for secondary batteries, and secondary battery negative electrodes and secondary batteries using it
JP6513896B2 (en) Aluminum alloy foil for lithium ion battery positive electrode current collector and method for producing the same
KR101971415B1 (en) Clad material for anode current collector of secondary battery and manufacturing method thereof
JP6860450B2 (en) Aluminum alloy plate for battery sealing material
CN113474476B (en) Aluminum alloy foil and method for producing same
JP2023178071A (en) Rolled copper foil for secondary batteries, and secondary battery negative electrode and method for producing secondary battery using the same
JP2023178067A (en) Rolled copper foil for secondary batteries, and secondary battery negative electrode and method for producing secondary battery using the same

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20080205

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100615

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100706

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100826

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20110510

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20110510

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140520

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

LAPS Cancellation because of no payment of annual fees