Copper foil Electrodeposited

Mesoporous tin was deposited from LLC surfactant phases in order to provide a nanostructured negative electrode material for applications in lithium ion batteries. Whitehead et al. [67,68] electrodeposited tin films from lyotropi-cally liquid crystalline solutions of tin sulfate in the hexagonal phase of Brij 76 onto copper foil. The authors further employed n-heptane as an inert swelling agent in order to tailor the dimensions of the resulting electrode materials. 

Common laminating resins used are phenolic and epoxy, although cyanate esters, polyimides, and other resins are used in specialty applications. The copper foil used is 99.5 percent pure and may contain some silver. Generally, electrodeposited foil is used rather than rolled copper, and the foil is usually treated to improve the adhesion of the laminating resin to the foil surface. 

Fang C, Foca E, Xu S, Carstensen J, Foil H (2007) Deep silicon macropores filled with copper by electrodeposition. J Electrochem Soc 154 D45... 

The most common foil used in manufacturing printed circuits is electrodeposited copper foil (ED foil). ED foil is produced through an electrochemical process in which copper feed stock or scrap copper wire is first dissolved in a sulfuric acid solution. The purified copper sulfate/ sulfuric acid solution is then used to electroplate copper onto a cylindrical drum typically made from stainless steel or titanium. Figure 7.20 illustrates the overall process used to make electrodeposited copper foil. This process results in a copper foil with a relatively smooth, shiny side, and a coarser matte side, as illustrated in Fig. 7.21.The shiny side mirrors the surface... 

The electrodeposited copper foils described above account for most of the conductive foils used in rigid printed circuits. However, modified versions of these foils are sometimes used in niche applications. These modified versions include double-treated copper foil and resistive foils. 

HTE or Class 3 copper foil exhibits improved elongation properties at elevated temperatures as compared to standard electrodeposited or Class 1 copper foil.Typical elongation values for HTE copper foil range from 4-10 percent at 180°C. 

Base substrates Conductors Copper-clad laminates Coverlay Adhesive layer Stiffener Polyimide film (PI), polyester film (PET), polyester telephthalate Thin glass-epoxy, fluorinated ethylene propylene (FEP), resin-coated paper Electrodeposited (ED) copper foil, RA copper foil, stainless steel foil, aluminum foil, etc. Epoxy-based, acrylic-based, phenol-based (adhesive-based) PI film, PET film, flexible solder mask Acrylic resin, epoxy resin, phenol resin, pressure-sensitive adhesives (PSAs) PI film, PET film, glass-epoxy, metal boards, etc. 

As flexible circuits have various mechanical stresses, their conductors also have requirements for more flexibility and toughness than traditional ED copper foils of standard rigid circuit boards. An RA copper foil is the solution for high flexing endurance. It is necessary for dynamic flexing use. RA copper foils are more expensive than ED copper, especially at thicknesses of less than 18 micron. Therefore, high-ductility electrodeposited (HD-ED) copper foils have been developed that have greater flexibility than ED copper foils and a lower cost than RA copper foils. The differences between the copper foils are shown in Table 61.11. 

Cycle performance of electrodes is dependent not only upon the active material but also strongly upon the morphology of the electrode as a whole including copper foil. One idea is to directly unify the iithium alloy active materials onto copper current collector. Electrodeposited tin-base electrodes " and vacuum-deposited electrodes, such as silicon, " and germanium ... 

Ultrasound has been used to improve the quality of copper during the industrial electrodeposition [22]. Using 20 kHz ultrasound (0.34 W cm ) and employing a copper anode (foil) and a copper cathode (sheet) led to less powdery brighter deposits. There was also a significant improvement in the current density from 60 A dm in the absence of ultrasound to 500 A dm in the presence. Work by Smirnov [42] has shown that coatings produced in the presence of ultrasound were smoother and harder. 

Since metallic Sn has a high capacity for reversible Li insertion, pure Sn as well as its intermetallic compounds have been considered as promising anode materials in lithium ion batteries. In intermetallic compounds of Sn, the second metal is normally electrochemically inactive and cannot be alloyed with Li. Such an inactive metal performs as a buffer to accommodate volume variations during Li insertion/deinsertion in Sn.224 Among various Sn intermetallic compounds, Ni3Sn4232-235 and CU6S115236 237 are the most commonly studied materials. Intermetallic compounds of Sn with Ni and Cu can be electrochemically deposited. Templates are conventionally used to improve the morphological properties and, thus, the electrochemical behavior of the electrodeposited Sn and Sn intermetallic compounds. Copper nanopillars can be electrodeposited within alumina templates on a Cu foil to provide a unique template for the subsequent electrodeposition of Sn or its intermetallic compounds. 

In the Reconwin cell [9] a uniform curtain of fine air bubbles is directed across the face of the cathode to increase the mass transfer coefficient in comparison to unagitated or recirculated electrolyte systems. Typically, at a concentration of 1 g dm, the limiting current for say copper deposition is approximately 100 A m . The cathode material is a permanent metal (stainless steel) blank of approximate size 0.6 m by 0.6 m, from which the electrodeposited metal is recovered as foil. The cell is used in an undivided configuration in which both sides of the cathode are active. 

Drum side treated (DSTFoil ) or reverse treated foil (RTF) is also an electrodeposited copper foU,bnt the treatments are coated onto the smooth drum side of the foil rather than the matte side, as with conventional electrodeposited foil (see Figs. 7.25 and 7.26).This results in a very-low-profUe surface bonded to the laminate, with the rough matte side facing out. The low... 

Nickel was electrodeposited on polished brass foil at different temperatures (Ni deposit roughness with temperature). Also, Martis et a/. reported that compact nickel multiwalled carbon nanotube composites eould be electrodeposited on a copper substrate using the eutectic mixture ChCl/EG as solvent. Later, electrodeposition of Ni-P alloys (with tunable phosphorous eontent) at room temperature was reported by You and co-workers. ... 

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