JPH1167218A - Perforated current collector used in secondary battery - Google Patents
Perforated current collector used in secondary batteryInfo
- Publication number
- JPH1167218A JPH1167218A JP9235386A JP23538697A JPH1167218A JP H1167218 A JPH1167218 A JP H1167218A JP 9235386 A JP9235386 A JP 9235386A JP 23538697 A JP23538697 A JP 23538697A JP H1167218 A JPH1167218 A JP H1167218A
- Authority
- JP
- Japan
- Prior art keywords
- current collector
- perforated current
- secondary battery
- perforated
- negative electrode
- 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.)
- Pending
Links
Classifications
-
- 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
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、二次電池、特にリ
チウム系二次電池に用いる負極用又は正極用集電体に関
するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current collector for a negative electrode or a positive electrode used in a secondary battery, particularly a lithium secondary battery.
【０００２】[0002]
【従来の技術】二次電池は、基本的には、正極，負極，
正極と負極とを絶縁するセパレーター，及び正極と負極
との間でイオンの移動を可能にするための電解液で構成
されている。正極及び負極は、金属箔からなる集電体の
表面に、各種の活物質が塗布されてなるものである。例
えば、リチウム系二次電池においては、正極として、コ
バルト酸リチウム等を含む活物質がアルミニウム箔より
なる集電体に塗布されてなるものが用いられ、一方、負
極としては、難黒鉛化カーボン等を含む活物質が銅箔よ
りなる集電体に塗布されてなるものが用いられている。2. Description of the Related Art A secondary battery is basically composed of a positive electrode, a negative electrode,
It is composed of a separator that insulates the positive electrode and the negative electrode, and an electrolytic solution that enables ions to move between the positive electrode and the negative electrode. The positive electrode and the negative electrode are formed by applying various active materials to a surface of a current collector made of a metal foil. For example, in a lithium secondary battery, a positive electrode is used in which an active material containing lithium cobaltate or the like is applied to a current collector made of aluminum foil, while a negative electrode is hardly graphitizable carbon or the like. An active material containing is coated on a current collector made of copper foil.
【０００３】一般に、アルミニウム箔や銅箔等の各種金
属箔面に、各種の活物質を塗布した場合、金属箔と活物
質とが一体化しにくく、比較的、活物質が脱落しやすい
ということがあった。二次電池作成の際、例えば、正極
及び負極の巻き上げの際に、活物質が脱落すると、所望
の容量を持つ二次電池が得られないという欠点が生じ
る。また、二次電池を作成した後に、活物質が脱落する
と、二次電池の充放電容量が徐々に低下してゆくという
欠点が生じる。In general, when various active materials are applied to various metal foil surfaces such as aluminum foil and copper foil, the metal foil and the active material are hardly integrated, and the active material is relatively easy to fall off. there were. When a secondary battery is manufactured, for example, when the active material falls off when the positive electrode and the negative electrode are wound up, there is a disadvantage that a secondary battery having a desired capacity cannot be obtained. Further, when the active material falls off after the secondary battery is manufactured, there is a disadvantage that the charge / discharge capacity of the secondary battery gradually decreases.
【０００４】このため、活物質中に混合するバインダー
として、金属箔との親和性に優れたものを用いることが
行なわれている。また、金属箔としても、その表面が、
各種バインダーとの親和性に優れたものを採用すること
が行なわれている。例えば、特開平７−２０１３３２号
公報には、銅箔表面に、ベンゾトリアゾール等のアゾー
ル系皮膜を形成し、活物質中のバインダーと銅箔との一
体化を向上させ、活物質の脱落を防止する技術が記載さ
れている。For this reason, it has been practiced to use a binder having an excellent affinity for a metal foil as a binder to be mixed into the active material. Also, the surface of the metal foil,
It has been practiced to employ those having excellent affinity with various binders. For example, JP-A-7-201332 discloses that an azole-based film such as benzotriazole is formed on a copper foil surface to improve the integration of a binder in the active material with the copper foil and prevent the active material from falling off. The technology to do this is described.
【０００５】一方、このような方法とは異なり、金属箔
に貫通孔を形成し、金属箔の表裏面に塗布される活物質
等を、貫通孔を通して一体化することによって、活物質
の脱落を防止する技術も知られている。On the other hand, unlike such a method, a through hole is formed in a metal foil, and the active material and the like applied to the front and back surfaces of the metal foil are integrated through the through hole to prevent the active material from falling off. Prevention techniques are also known.
【０００６】しかし、金属箔に貫通孔を形成してなる集
電体は、集電体の平面方向における電気抵抗（Ω）が増
加して、高率放電時における電池容量の低下が激しく、
二次電池の放電時間が短くなるという欠点があった。こ
のため、集電体を構成する金属箔の厚みを厚くして、電
気抵抗（Ω）の増加を抑え、電池容量の低下が激しくな
るのを防止することが試みられている。However, in a current collector formed with a through-hole in a metal foil, the electric resistance (Ω) in the plane direction of the current collector increases, and the battery capacity at the time of high-rate discharge is greatly reduced.
There is a disadvantage that the discharge time of the secondary battery is shortened. For this reason, attempts have been made to increase the thickness of the metal foil constituting the current collector, to suppress an increase in electric resistance (Ω), and to prevent a sharp decrease in battery capacity.
【０００７】しかしながら、金属箔の厚み（即ち、集電
体の厚み）を厚くすると、二次電池の重量が重くなる或
いは二次電池の容積が大きくなり、単位重量当たり或い
は単位容積当たりの電池容量が小さくなる。従って、二
次電池が組み込まれた電気自動車や携帯電話等の製品の
軽量化や小型化が図れないという別の欠点を惹起するに
到る。However, when the thickness of the metal foil (that is, the thickness of the current collector) is increased, the weight of the secondary battery is increased or the volume of the secondary battery is increased, and the battery capacity per unit weight or unit volume is increased. Becomes smaller. Therefore, another drawback arises in that it is not possible to reduce the weight and size of products such as electric vehicles and mobile phones in which a secondary battery is incorporated.
【０００８】[0008]
【発明が解決しようとする課題】そこで、本発明は、集
電体を構成する金属箔の材料（金属）自体及び孔開きの
程度を調整することによって、比較的厚みの薄い集電体
であっても、電気抵抗（Ω）の増加を抑え、高率放電時
における電池容量の大きな低下を防止しようというもの
である。換言すれば、本発明は、多数の貫通孔が設けら
れている孔開き集電体の平面方向における電気抵抗
（Ω）を、集電体を構成する金属箔の材料自体及び孔開
きの程度を調整することによって、一定範囲に設定し、
高率放電時における電池容量の大きな低下を防止しよう
というものである。SUMMARY OF THE INVENTION Accordingly, the present invention provides a current collector having a relatively small thickness by adjusting the material (metal) of the metal foil constituting the current collector and the degree of perforation. However, it is intended to suppress an increase in electric resistance (Ω) and prevent a large decrease in battery capacity during high-rate discharge. In other words, the present invention determines the electric resistance (Ω) in the plane direction of the perforated current collector provided with a large number of through holes, by changing the material itself of the metal foil constituting the current collector and the degree of perforation. By adjusting, set a certain range,
It is intended to prevent a large decrease in battery capacity during high-rate discharge.
【０００９】[0009]
【課題を解決するための手段】即ち、本発明は、多数の
貫通孔が設けられている金属箔からなる孔開き集電体の
平面方向における電気抵抗（Ω）を、一定範囲に設定し
た二次電池の負極用又は正極用集電体に関するものであ
る。また、本発明は、多数の貫通孔が設けられている金
属箔からなる孔開き集電体において、金属箔の構成材料
の比抵抗（Ω・ｃｍ），集電体の厚み（ｃｍ）及び開口
率（無単位）よりなる三者の特定の関係を、一定範囲に
設定した二次電池の負極用又は正極用集電体に関するも
のである。That is, according to the present invention, the electric resistance (Ω) in the plane direction of a perforated current collector made of a metal foil having a large number of through holes is set within a predetermined range. The present invention relates to a current collector for a negative electrode or a positive electrode of a secondary battery. Further, the present invention provides a perforated current collector made of a metal foil provided with a large number of through holes, the specific resistance (Ω · cm) of the constituent material of the metal foil, the thickness (cm) of the current collector, and the opening. The present invention relates to a current collector for a negative electrode or a positive electrode of a secondary battery in which a specific relationship among the three ratios (unitless) is set within a certain range.
【００１０】本発明においては、孔開き集電体を構成す
る金属箔としては、任意の金属材料からなるものが用い
られるが、好ましくは、アルミニウム箔，アルミニウム
合金箔，銅箔又は銅合金箔が良い。リチウム系二次電池
の場合、正極に用いる集電体は、一般的にアルミニウム
箔又はアルミニウム合金箔であり、一方、負極に用いる
集電体は、一般的に銅箔又は銅合金箔である。In the present invention, as the metal foil constituting the perforated current collector, any metal material may be used. Preferably, an aluminum foil, an aluminum alloy foil, a copper foil or a copper alloy foil is used. good. In the case of a lithium secondary battery, the current collector used for the positive electrode is generally an aluminum foil or an aluminum alloy foil, while the current collector used for the negative electrode is generally a copper foil or a copper alloy foil.
【００１１】孔開き集電体の厚みは、５〜１００μｍで
あるのが好ましい。厚みが５μｍ未満であると、集電体
自体の機械的強度が低下し、二次電池作成時における、
集電体の巻き上げ時に、集電体が破断する恐れがある。
また、厚みが１００μｍを超えると、二次電池の重量が
重くなりすぎ或いはその容積が大きくなりすぎて、二次
電池の軽量化及び小型化が図れないため、好ましくな
い。具体的には、リチウム系二次電池の負極用銅箔製集
電体の場合は、８〜２５μｍ程度であるのが好ましく、
正極用アルミニウム箔製集電体の場合は、１０〜３０μ
ｍであるのが好ましい。なお、銅箔としては、圧延銅箔
（圧延法で得られる銅箔）であっても、電解銅箔（電解
法で得られる銅箔）のいずれであっても良い。The thickness of the perforated current collector is preferably 5 to 100 μm. If the thickness is less than 5 μm, the mechanical strength of the current collector itself decreases,
When the current collector is wound up, the current collector may be broken.
On the other hand, if the thickness exceeds 100 μm, the weight of the secondary battery becomes too heavy or its volume becomes too large, so that the weight and size of the secondary battery cannot be reduced. Specifically, in the case of a current collector made of copper foil for a negative electrode of a lithium secondary battery, the thickness is preferably about 8 to 25 μm,
In the case of a current collector made of aluminum foil for a positive electrode, 10 to 30 μm
m is preferred. The copper foil may be a rolled copper foil (a copper foil obtained by a rolling method) or an electrolytic copper foil (a copper foil obtained by an electrolytic method).
【００１２】集電体に設けられている貫通孔の形状は、
一般的には円形であるが、その他、三角形や四角形等の
任意の形状であって良い。また、貫通孔の大きさは、二
次電池の種類や大きさ或いは用途によって、任意の大き
さとすることができる。更に、貫通孔は、集電体に多数
設けられており、例えば、貫通孔間のピッチは０．５〜
１０ｍｍ程度で良く、貫通孔の密度は１〜４００個／ｃ
ｍ2程度で良い。The shape of the through hole provided in the current collector is as follows:
Generally, the shape is circular, but any other shape such as a triangle or a quadrangle may be used. Further, the size of the through hole can be set to an arbitrary size depending on the type, size, or use of the secondary battery. Furthermore, a large number of through holes are provided in the current collector, and for example, the pitch between the through holes is 0.5 to
It may be about 10 mm, and the density of through holes is 1 to 400 / c.
m 2 is sufficient.
【００１３】本発明の特徴は、このような孔開き集電体
の平面方向における電気抵抗（Ω）を、以下の如き範囲
に設定することである。即ち、二次電池の負極用集電体
の場合には、２０℃の温度で測定した電気抵抗（Ω）
を、１．７×１０-4Ω〜３．５×１０-2Ωの範囲内とす
ることである。この電気抵抗を１．７×１０-4Ω未満に
することは、比較的厚みの薄い集電体に孔を穿つ限り、
現実的には困難である。また、この電気抵抗が３．５×
１０-2Ωを超えると、高率放電時の二次電池容量の低下
が激しくなり、好ましくない。一方、二次電池の正極用
集電体の場合には、２０℃の温度で測定した電気抵抗
（Ω）を、２．７×１０-4Ω〜５．４×１０-2Ωの範囲
内とすることである。この電気抵抗を２．７×１０-4Ω
未満とすることは、比較的厚みの薄い集電体に孔を穿つ
限り、現実的には困難である。また、この電気抵抗が
５．４×１０-2Ωを超えると、高率放電時の二次電池容
量の低下が激しくなり、好ましくない。A feature of the present invention is that the electric resistance (Ω) in the plane direction of such a perforated current collector is set in the following range. That is, in the case of the negative electrode current collector of the secondary battery, the electric resistance (Ω) measured at a temperature of 20 ° C.
Within a range of 1.7 × 10 −4 Ω to 3.5 × 10 −2 Ω. Making this electric resistance less than 1.7 × 10 −4 Ω is as long as a hole is made in a relatively thin current collector.
Realistically difficult. The electric resistance is 3.5 ×
If it exceeds 10 -2 Ω, the capacity of the secondary battery at the time of high-rate discharge is greatly reduced, which is not preferable. On the other hand, in the case of the current collector for the positive electrode of the secondary battery, the electric resistance (Ω) measured at a temperature of 20 ° C. is in the range of 2.7 × 10 −4 Ω to 5.4 × 10 −2 Ω. It is to be. This electric resistance is 2.7 × 10 −4 Ω
It is practically difficult to reduce the thickness to less than as long as a hole is formed in a relatively thin current collector. On the other hand, if the electric resistance exceeds 5.4 × 10 -2 Ω, the capacity of the secondary battery at the time of high-rate discharge is greatly reduced, which is not preferable.
【００１４】本発明において、孔開き集電体の平面方向
における電気抵抗（Ω）は、以下の如き方法で測定され
るものである。まず、孔開き集電体の任意の箇所から１
０ｃｍ×１０ｃｍの大きさの試料を採取する。そして、
この試料の右端と左端にリード線を接続し、一定の電流
（Ｉ）を流し、右端と左端との間の電圧（Ｖ）を測定す
る。そして、Ｖ／Ｉの計算して、電気抵抗（Ω）を算出
するのである。なお、孔開き集電体の大きさが小さすぎ
て、１０ｃｍ×１０ｃｍの大きさの試料が採取できない
場合は、次のいずれかの方法を用いて電気抵抗（Ω）を
測定する。即ち、測定しようとする孔開き集電体を作成
した孔開き集電体材料から、１０ｃｍ×１０ｃｍの大き
さの試料を採取し、電気抵抗（Ω）を測定する。また
は、孔開き集電体から、１０ｃｍ×１０ｃｍよりも小さ
い正方形の試料を採取し、これを被測定試料として、上
記の方法により電気抵抗を測定し、その値を１０ｃｍ×
１０ｃｍの大きさに換算して、電気抵抗（Ω）とする。
また、電気抵抗の測定の際、試料の温度は２０℃とす
る。In the present invention, the electric resistance (Ω) in the plane direction of the perforated current collector is measured by the following method. First, from any point on the perforated current collector,
A sample having a size of 0 cm × 10 cm is taken. And
Lead wires are connected to the right and left ends of the sample, a constant current (I) is passed, and a voltage (V) between the right and left ends is measured. Then, the electrical resistance (Ω) is calculated by calculating V / I. If the size of the perforated current collector is too small to collect a sample having a size of 10 cm × 10 cm, the electric resistance (Ω) is measured using one of the following methods. That is, a sample having a size of 10 cm × 10 cm is collected from the perforated current collector material on which the perforated current collector to be measured is prepared, and the electric resistance (Ω) is measured. Alternatively, a square sample smaller than 10 cm × 10 cm is sampled from the perforated current collector, and the obtained sample is used as a sample to be measured, and the electric resistance is measured by the above method.
Converted to a size of 10 cm, it is defined as electric resistance (Ω).
In measuring the electric resistance, the temperature of the sample is set to 20 ° C.
【００１５】本発明においては、孔開き集電体のどの箇
所から試料を採取した場合であっても、電気抵抗（Ω）
が一定の範囲内になければならない。即ち、二次電池の
負極用孔開き集電体の場合には、どの箇所から試料を採
取しても、常に１．７×１０-4Ω〜３．５×１０-2Ωの
範囲内でなければならない。また、二次電池の正極用孔
開き集電体の場合には、どの箇所から試料を採取して
も、常に２．７×１０-4Ω〜５．４×１０-2Ωの範囲内
でなければならない。一箇所でも、この範囲を超える電
気抵抗（Ω）の箇所があると、高率放電時の二次電池容
量の低下が激しくなり、好ましくない。なお、孔開き集
電体から試料を採取する箇所は、孔開き集電体の本体部
であることは言うまでもない、リード部（電気を取り出
すために、本体部に接続された線状板部）は含まない。[0015] In the present invention, the electrical resistance (Ω) can be obtained regardless of where the sample is taken from the perforated current collector.
Must be within a certain range. That is, in the case of a perforated current collector for a negative electrode of a secondary battery, no matter where the sample is taken, it always falls within the range of 1.7 × 10 −4 Ω to 3.5 × 10 −2 Ω. There must be. In the case of a perforated current collector for a positive electrode of a secondary battery, no matter where the sample is taken, the current is always within the range of 2.7 × 10 −4 Ω to 5.4 × 10 −2 Ω. There must be. It is not preferable that even at one location, a location having an electrical resistance (Ω) exceeding this range greatly reduces the capacity of the secondary battery during high-rate discharge. It is needless to say that the place where the sample is collected from the perforated current collector is the main body of the perforated current collector, and the lead portion (a linear plate portion connected to the main body to extract electricity). Is not included.
【００１６】上記のような電気抵抗（Ω）を持つ集電体
は、集電体の開口率（無単位），集電体の厚み（ｃｍ）
及び集電体を構成している金属材料の比抵抗（Ω・ｃ
ｍ）を種々調整することによって得ることができる。例
えば、二次電池の負極用孔開き集電体の場合には、集電
体の開口率をＱ（無単位）とし、集電体の厚みをｔ（ｃ
ｍ）とし、集電体を構成している金属材料の比抵抗をρ
（Ω・ｃｍ）としたとき、ρ／［ｔ×（１−Ｑ）］の値
が１．７×１０-4Ω〜３．５×１０-2Ωとなるようにす
れば良い。この値を１．７×１０-4Ω未満にすること
は、比較的厚みの薄い集電体に孔を穿つ限り、現実的に
は困難である。また、この値が３．５×１０-2Ωを超え
ると、高率放電時の二次電池容量の低下が激しくなり、
好ましくない。また、二次電池の正極用孔開き集電体の
場合には、ρ／［ｔ×（１−Ｑ）］の値が２．７×１０
-4Ω〜５．４×１０-2Ωとなるようにすれば良い。この
値を２．７×１０-4Ω未満とすることは、比較的厚みの
薄い集電体に孔を穿つ限り、現実的には困難である。ま
た、この値が５．４×１０-2Ωを超えると、高率放電時
の二次電池容量の低下が激しくなり、好ましくない。The current collector having the electric resistance (Ω) as described above has a current collector aperture ratio (no unit) and a current collector thickness (cm).
And the specific resistance (Ω · c) of the metal material constituting the current collector
m) can be obtained by adjusting variously. For example, in the case of a perforated current collector for a negative electrode of a secondary battery, the aperture ratio of the current collector is Q (unitless), and the thickness of the current collector is t (c
m), and the specific resistance of the metal material forming the current collector is ρ
(Ω · cm), the value of ρ / [t × (1-Q)] should be 1.7 × 10 −4 Ω to 3.5 × 10 −2 Ω. It is practically difficult to make this value less than 1.7 × 10 −4 Ω as long as a hole is formed in a relatively thin current collector. Further, when this value exceeds 3.5 × 10 -2 Ω, the capacity of the secondary battery at the time of high-rate discharge decreases significantly,
Not preferred. Further, in the case of a perforated current collector for a positive electrode of a secondary battery, the value of ρ / [t × (1-Q)] is 2.7 × 10
-4 Ω to 5.4 × 10 -2 Ω. It is practically difficult to make this value less than 2.7 × 10 −4 Ω as long as a hole is formed in a relatively thin current collector. On the other hand, if this value exceeds 5.4 × 10 -2 Ω, the capacity of the secondary battery at the time of high-rate discharge is greatly reduced, which is not preferable.
【００１７】ここで、集電体の開口率Ｑ（無単位）は、
以下の如き方法で算出されるものである。即ち、集電体
の表面積（見掛け上の表面積）をＳとし、貫通孔の全面
積（各貫通孔の面積の総和）をＰとした場合、開口率Ｑ
＝Ｐ／Ｓである。例えば、幅５０ｃｍで長さ８０ｃｍの
集電体に、１ｃｍ2の面積の貫通孔が１０００個穿たれ
ている場合には、Ｓ＝４０００ｃｍ2でＰ＝１０００ｃ
ｍ2となり、Ｑ＝０．２５となる。なお、集電体の表面
積は、集電体本体の表面積であり、リード部の表面積を
含まないことは言うまでもない。Here, the aperture ratio Q (unitless) of the current collector is
It is calculated by the following method. That is, when the surface area (apparent surface area) of the current collector is S and the total area of the through holes (sum of the areas of the respective through holes) is P, the aperture ratio Q
= P / S. For example, if a current collector having a width of 50 cm and a length of 80 cm is provided with 1000 through-holes having an area of 1 cm 2 , S = 4000 cm 2 and P = 1000 c
m 2 and Q = 0.25. Needless to say, the surface area of the current collector is the surface area of the current collector body and does not include the surface area of the lead portion.
【００１８】また、集電体の厚み（ｃｍ）は、集電体の
非孔区域における厚みであり、任意の５箇所における非
孔区域の厚みの平均値を、集電体の厚みとする。比抵抗
（Ω・ｃｍ）は、物質に固有の定数であり、本発明にお
いては、集電体を構成している金属材料の比抵抗（Ω・
ｃｍ）である。従って、金属材料の元素組成により、そ
の値は種々に変動する。なお、この比抵抗（Ω・ｃｍ）
は、金属材料の温度を２０℃として、測定されるもので
ある。The thickness (cm) of the current collector is the thickness in the non-porous area of the current collector, and the average value of the thickness of the non-porous area at any five places is defined as the thickness of the current collector. The specific resistance (Ω · cm) is a constant peculiar to a substance, and in the present invention, the specific resistance (Ω · cm) of the metal material forming the current collector is used.
cm). Therefore, the value varies variously depending on the elemental composition of the metal material. In addition, this specific resistance (Ωcm)
Is measured at a temperature of the metal material of 20 ° C.
【００１９】本発明においては、開口率Ｑは、具体的に
は０．０１〜０．９０の範囲で、任意の値が採用される
ことが多い。開口率が０．０１未満であると、孔開き集
電体とは言い難く、活物質等の脱落を十分に防止できな
い憾みがある。また、開口率が０．９０を超えると、集
電体自体の機械的強度が低下する傾向が生じる。開口率
Ｑは、０．１〜０．５の範囲の任意の値であるのが好ま
しく、特に０．２前後であるのが最も好ましい。In the present invention, an arbitrary value is often adopted as the aperture ratio Q, specifically, in the range of 0.01 to 0.90. When the aperture ratio is less than 0.01, it is difficult to say that the current collector is a perforated current collector, and there is a regret that the falling of the active material or the like cannot be sufficiently prevented. When the aperture ratio exceeds 0.90, the mechanical strength of the current collector itself tends to decrease. The aperture ratio Q is preferably any value in the range of 0.1 to 0.5, and most preferably around 0.2.
【００２０】集電体の厚みｔは、具体的には０．０００
５〜０．０１ｃｍの範囲で、任意の厚みのものが採用さ
れることが多い。厚みが０．０００５ｃｍ未満である
と、集電体自体の機械的強度が低下する傾向が生じる。
また、厚みが０．０１ｃｍを超えると、集電体の重量が
重くなり或は容積が大きくなり、二次電池の軽量化或は
小型化が図れない傾向が生じる。例えば、二次電池の負
極用孔開き集電体の場合には、厚みは０．０００８〜
０．００２５ｃｍの範囲であるのが好ましい。また、正
極用孔開き集電体の場合には、厚みが０．００１〜０．
００３ｃｍの範囲であるのが好ましい。The thickness t of the current collector is specifically 0.000
In a range of 5 to 0.01 cm, an arbitrary thickness is often adopted. If the thickness is less than 0.0005 cm, the mechanical strength of the current collector itself tends to decrease.
On the other hand, when the thickness exceeds 0.01 cm, the current collector becomes heavier or larger in volume, which tends to make it difficult to reduce the weight or size of the secondary battery. For example, in the case of a perforated current collector for a negative electrode of a secondary battery, the thickness is 0.0008 to
Preferably it is in the range of 0.0025 cm. In the case of a perforated current collector for the positive electrode, the thickness is 0.001 to 0.
It is preferably in the range of 003 cm.
【００２１】集電体を構成する金属材料としては、銅や
アルミニウム等の従来公知の金属を用いることができ
る。また、銅やアルミニウムに、任意の元素を微量添加
した合金も用いることができる。例えば、比抵抗が１．
７５×１０-6Ω・ｃｍのタフピッチ銅や、２．６９×１
０-6Ω・ｃｍの３Ｎアルミニウムを用いることができ
る。集電体は、周知のように金属箔よりなるものである
から、これらの金属材料を圧延加工等の方法によって箔
とすれば良い（銅の場合には電解法によっても良い）。As the metal material constituting the current collector, conventionally known metals such as copper and aluminum can be used. Further, an alloy obtained by adding a trace amount of an arbitrary element to copper or aluminum can also be used. For example, if the specific resistance is 1.
75 × 10 −6 Ω · cm tough pitch copper or 2.69 × 1
3N aluminum 0 -6 Ω · cm can be used. Since the current collector is made of a metal foil as is well known, the metal material may be formed into a foil by a method such as rolling (or an electrolytic method in the case of copper).
【００２２】以上の如き特定の電気抵抗（Ω）、或いは
特定のρ／［ｔ×（１−Ｑ）］の値を持つ、多数の貫通
孔が形成された集電体は、リチウムイオン電池，金属リ
チウム電池，ポリマー電池等のリチウム系二次電池の負
極用又は正極用孔開き集電体として好適に用いられる。
また、リチウム系二次電池以外の二次電池の負極用又は
正極用孔開き集電体としても、好適に用いられる。The current collector having a specific electric resistance (Ω) or a specific value of ρ / [t × (1-Q)] and formed with a large number of through holes is a lithium ion battery, It is suitably used as a perforated current collector for a negative electrode or a positive electrode of a lithium secondary battery such as a metal lithium battery and a polymer battery.
It is also suitably used as a perforated current collector for a negative electrode or a positive electrode of a secondary battery other than a lithium secondary battery.
【００２３】[0023]
【作用及び発明の効果】本発明に係る二次電池の負極用
又は正極用孔開き集電体は、平面方向における電気抵抗
（Ω）又はρ／［ｔ×（１−Ｑ）］の値が一定の範囲内
に設定されているので、高率放電時に過大な電流が集電
体に流れても、即ち、大電流放電が生じても、集電体内
でのＩＲドロップが大きくなるのを防止でき、電池容量
が大きく低下するのを防止することができる。従って、
二次電池の放電時間を延ばすことができ、一回の充電で
長時間使用が可能になるという効果を奏する。The perforated current collector for the negative electrode or the positive electrode of the secondary battery according to the present invention has a value of electric resistance (Ω) or ρ / [t × (1-Q)] in the plane direction. Since it is set within a certain range, even if an excessive current flows to the current collector during high-rate discharge, that is, even if a large current discharge occurs, it is possible to prevent the IR drop in the current collector from becoming large. It is possible to prevent the battery capacity from greatly decreasing. Therefore,
This has the effect that the discharge time of the secondary battery can be extended, and that a single charge can be used for a long time.
【００２４】また、本発明に係る二次電池の負極用又は
正極用孔開き集電体は、集電体のどの箇所においても、
平面方向における電気抵抗（Ω）又はρ／［ｔ×（１−
Ｑ）］の値が一定の範囲内に設定されているので、負極
又は正極の表面における電流分布が均一になり、部分的
な活物質の劣化が起こりにくくなり、二次電池の寿命を
も長くすることができるという効果を奏する。Further, the perforated current collector for the negative electrode or the positive electrode of the secondary battery according to the present invention may be provided at any position of the current collector.
Electric resistance (Ω) in the plane direction or ρ / [t × (1-
Q)] is set within a certain range, so that the current distribution on the surface of the negative electrode or the positive electrode becomes uniform, partial deterioration of the active material hardly occurs, and the life of the secondary battery is prolonged. It has the effect that it can be done.
Claims (10)
らなる孔開き集電体であって、該孔開き集電体の任意の
箇所から採取した１０ｃｍ×１０ｃｍの金属箔を試料と
し、該試料の左端と右端との間における平面方向の電気
抵抗（但し、２０℃で測定）が、常に１．７×１０-4Ω
〜３．５×１０-2Ωの範囲内であることを特徴とする二
次電池の負極用孔開き集電体。1. A perforated current collector made of a metal foil provided with a large number of through-holes, and a 10 cm × 10 cm metal foil collected from an arbitrary portion of the perforated current collector as a sample, The electric resistance in the plane direction between the left end and the right end of the sample (measured at 20 ° C.) is always 1.7 × 10 −4 Ω.
The negative electrode for the perforated current collector of a secondary battery, characterized in that to 3.5 in the range of × 10 -2 Ω.
らなる孔開き集電体であって、該孔開き集電体の任意の
箇所から採取した１０ｃｍ×１０ｃｍの金属箔を試料と
し、該試料の左端と右端との間における平面方向の電気
抵抗（但し、２０℃で測定）が、常に２．７×１０-4Ω
〜５．４×１０-2Ωの範囲内であることを特徴とする二
次電池の正極用孔開き集電体。2. A perforated current collector made of a metal foil provided with a large number of through-holes, and a 10 cm × 10 cm metal foil collected from an arbitrary portion of the perforated current collector is used as a sample. The electrical resistance in the plane direction between the left end and the right end of the sample (measured at 20 ° C.) is always 2.7 × 10 −4 Ω.
A perforated current collector for a positive electrode of a secondary battery, wherein the current collector falls within a range of ５5.4 × 10 −2 Ω.
らなる孔開き集電体であって、該孔開き集電体の開口率
をＱ（無単位）とし、該孔開き集電体の厚みをｔ（ｃ
ｍ）とし、該孔開き集電体を構成する金属固有の比抵抗
をρ（Ω・ｃｍ）（但し、２０℃で測定）としたとき、
ρ／［ｔ×（１−Ｑ）］の値が１．７×１０-4Ω〜３．
５×１０-2Ωであることを特徴とする二次電池の負極用
孔開き集電体。3. A perforated current collector comprising a metal foil provided with a large number of through holes, wherein the aperture ratio of the perforated current collector is Q (unitless), and the perforated current collector is T (c)
m), and the specific resistance of the metal constituting the perforated current collector is ρ (Ω · cm) (measured at 20 ° C.)
The value of ρ / [t × (1-Q)] is 1.7 × 10 −4 Ω to 3.
A perforated current collector for a negative electrode of a secondary battery, wherein the current collector is 5 × 10 −2 Ω.
らなる孔開き集電体であって、該孔開き集電体の開口率
をＱ（無単位）とし、該孔開き集電体の厚みをｔ（ｃ
ｍ）とし、該孔開き集電体を構成する金属固有の比抵抗
をρ（Ω・ｃｍ）（但し、２０℃で測定）としたとき、
ρ／［ｔ×（１−Ｑ）］の値が２．７×１０-4Ω〜５．
４×１０-2Ωであることを特徴とする二次電池の正極用
孔開き集電体。4. A perforated current collector comprising a metal foil provided with a large number of through holes, wherein the aperture ratio of the perforated current collector is Q (unitless), and the perforated current collector is T (c)
m), and the specific resistance of the metal constituting the perforated current collector is ρ (Ω · cm) (measured at 20 ° C.)
The value of ρ / [t × (1-Q)] is 2.7 × 10 −4 Ω to 5.
A perforated current collector for a positive electrode of a secondary battery, wherein the current collector is 4 × 10 −2 Ω.
ある請求項１乃至４のいずれか一項に記載の二次電池の
負極用又は正極用孔開き集電体。5. The perforated current collector for a negative electrode or a positive electrode of a secondary battery according to claim 1, wherein the perforated current collector has a thickness of 5 to 100 μm.
１又は３記載の二次電池の負極用孔開き集電体。6. The perforated current collector for a negative electrode of a secondary battery according to claim 1, wherein the metal foil is a copper foil or a copper alloy foil.
る請求項６記載の二次電池の負極用孔開き集電体。7. The perforated current collector for a negative electrode of a secondary battery according to claim 6, wherein the perforated current collector has a thickness of 8 to 25 μm.
ム合金箔である請求項２又は４記載の二次電池の正極用
孔開き集電体。8. The perforated current collector for a positive electrode of a secondary battery according to claim 2, wherein the metal foil is an aluminum foil or an aluminum alloy foil.
ある請求項８記載の二次電池の正極用孔開き集電体。9. The perforated current collector for a positive electrode of a secondary battery according to claim 8, wherein the perforated current collector has a thickness of 10 to 30 μm.
属リチウム電池又はポリマー電池である請求項１乃至９
のいずれか一項に記載の二次電池の負極用又は正極用孔
開き集電体。10. The battery according to claim 1, wherein the secondary battery is a lithium ion battery, a metal lithium battery, or a polymer battery.
The perforated current collector for a negative electrode or a positive electrode of the secondary battery according to any one of the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9235386A JPH1167218A (en) | 1997-08-14 | 1997-08-14 | Perforated current collector used in secondary battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9235386A JPH1167218A (en) | 1997-08-14 | 1997-08-14 | Perforated current collector used in secondary battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH1167218A true JPH1167218A (en) | 1999-03-09 |
Family
ID=16985322
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9235386A Pending JPH1167218A (en) | 1997-08-14 | 1997-08-14 | Perforated current collector used in secondary battery |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH1167218A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9548497B2 (en) | 2011-06-10 | 2017-01-17 | Eaglepicher Technologies, Llc | Layered composite current collector with plurality of openings, methods of manufacture thereof, and articles including the same |
-
1997
- 1997-08-14 JP JP9235386A patent/JPH1167218A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9548497B2 (en) | 2011-06-10 | 2017-01-17 | Eaglepicher Technologies, Llc | Layered composite current collector with plurality of openings, methods of manufacture thereof, and articles including the same |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5547782A (en) | Current collector for lithium ion battery | |
| CA1310361C (en) | Battery | |
| EP2903063A1 (en) | Collector, electrode structure, nonaqueous electrolyte battery, conductive filler, and electricity storage component | |
| EP2586084A2 (en) | Lithium ion battery | |
| JPH08170126A (en) | Porous metallic body, its production and plate for battery using the same | |
| JPH1186845A (en) | Nonaqueous secondary battery | |
| JPH11339811A (en) | Copper alloy foil current collector for secondary battery | |
| JP2009199744A (en) | Negative electrode for lithium secondary battery and its manufacturing method | |
| JP3649373B2 (en) | Method for producing negative electrode current collector for secondary battery | |
| JPH1167218A (en) | Perforated current collector used in secondary battery | |
| JP3387381B2 (en) | Alkaline storage battery | |
| JP2000306574A (en) | Manufacture of battery electrode | |
| JPH1197035A (en) | Banboo blind like perforated circuit collector used for secondary cell | |
| JPS63308868A (en) | Secondary cell | |
| JPH117952A (en) | Paste type nickel plate | |
| JP2013232295A (en) | Positive electrode for nonaqueous electrolyte secondary battery, manufacturing method therefor, and nonaqueous electrolyte secondary battery using positive electrode for nonaqueous electrolyte secondary battery | |
| JP2013214374A (en) | Positive electrode for nonaqueous electrolytic secondary batteries, and nonaqueous electrolytic secondary battery using the same | |
| WO2023195233A1 (en) | Negative electrode for zinc battery, and zinc battery | |
| JP2975616B2 (en) | Nickel oxide / hydrogen storage alloy secondary battery | |
| JP2004079198A (en) | Lead accumulator | |
| JPS622453A (en) | Hydrogen-occlusion alloy electrode | |
| JP6071407B2 (en) | Al-Si alloy current collector used for positive electrode for nonaqueous electrolyte secondary battery and method for producing the same, positive electrode for nonaqueous electrolyte secondary battery using the current collector and method for producing the same, and non-electrode using the positive electrode Water electrolyte secondary battery | |
| Hauke et al. | Investigations on rechargeable lithium alloys on the basis of Al Ni and Al Mn alloys | |
| JPS61233966A (en) | Manufacture of sealed nickel-hydrogen storage battery | |
| JPS6396869A (en) | Aluminum alloy for negative electrode material of lithium secondary battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20040812 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20061110 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070925 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20080311 |