Cellulose Paper + Nano-technology An Overview of the battery technology that powers our mobile society. ___________________________ ?

INTRODUCTION The creation of the paper battery drew from a diverse pool of disciplanes, requiring expertise in materials science, energy storage and chemistry. In august 2007, a research team at Rensselear polytechnic Institute led by Drs. Robert Linhardt, the Ann and John H.Broad Bent, senior constellation professors of bio catalysis and Metabolic engineering at Rensselaer, the Pulickel M.Ajayan, Professor of materials science and engineering AND Omkaram Nalamasu, professor of chemistry with a joint appointment in Material science and engineering developed the paper battery, also known as nano composite paper.

Battery Chemistry Electrochemical reaction - a chemical reaction between elements which creates electrons. Oxidation occurs on the metals (“electrodes”), which creates the electrons. Electrons are transferred down the pile via the saltwater paper (the “electrolyte”). A charge is introduced at one pole, which builds as it moves down the pile.

Recharge-ability & the “memory effect” Recharge-ability: basically, when the direction of electron discharge (negative to positive) is reversed, restoring power. Memory Effect The Memory Effect: (generally) When a battery is repeatedly recharged before it has discharged more than half of its power, it will “forget” its original power capacity. Cadmium crystals are the culprit! (NiCd)

Lithium (Ion) Battery Development Lithium-cobalt oxidegraphite In the 1970’s, Lithium metal was used but its instability rendered it unsafe and impractical. Lithium-cobalt oxide and graphite are now used as the lithium-Ion-moving electrodes. The Lithium-Ion battery has a slightly lower energy density than Lithium metal, but is much safer. Introduced by Sony in

Advantages of Using Li-Ion Batteries POWER POWER – High energy density means greater power in a smaller package. 160% greater than NiMH 220% greater than NiCd HIGHER VOLTAGE HIGHER VOLTAGE – a strong current allows it to power complex mechanical devices. LONG SHELF-LIFE LONG SHELF-LIFE – only 5% discharge loss per month. 10% for NiMH, 20% for NiCd

Disadvantages of Li-Ion EXPENSIVE EXPENSIVE -- 40% more than NiCd. DELICATE DELICATE -- battery temp must be monitored from within (which raises the price), and sealed particularly well. REGULATIONS REGULATIONS -- when shipping Li-Ion batteries in bulk (which also raises the price). Class 9 miscellaneous hazardous material UN Manual of Tests and Criteria (III, 38.3)

Environmental Impact of Li-Ion Batteries Rechargeable batteries are often recyclable. Oxidized Lithium is non-toxic, and can be extracted from the battery, neutralized, and used as feedstock for new Li-Ion batteries.

The Intersection “In terms of weight and size, batteries have become one of the limiting factors in the development of electronic devices.” “The problem with...lithium batteries is that none of the existing electrode materials alone can deliver all the required performance characteristics including high capacity, higher operating voltage, and long cycle life. Consequently, the other way is to optimize available electrode materials by designing new composite structures on the nanoscale.”

“Nano”-Science and -Technology The attempt to manufacture and control objects at the atomic and molecular level (i.e. 100 nanometers or smaller). 1 nanometer = 1 billionth of a meter (10 -9 ) 1 nanometer : 1 meter :: 1 marble : Earth 1 sheet of paper = 100,000 nanometers

Nano + Li-Ion = ? commercial Nanotechnology and Li-Ion applications in the commercial sector are apparent... lighter, more powerful batteries increase user mobility and equipment life. DeWalt 36volt cordless power tools residential Nanotechnology & Li-Ion applications in the residential sector are not so obvious... Micro-generated energy storage?

Micro-Generated Energy Storage Li-Ion batteries’ high energy density allows batteries them to power complex machinery. Li-Ion batteries recharge quickly and hold their charge longer, which provides flexibility to the micro-generator. particularly helpful for wind and solar generators! Lightness, and power per volume allow for storage and design flexibility.

It is a hybrid energy storage device that combines characteristics of batteries and super capacitors. It takes the high energy storage capacity of the battery and the high energy density of the super capacitor which producing bursts of extreme power. What is Nanocomposite paper

Materials and Description This energy storage device is based on two basic, inexpensive materials: carbon nanotubes and cellulose. Also an ionic liquid provides the third component: electrolyte. Engineered together, they form nanocomposite paper. It is as thin and flexible as a piece of paper—it can be twisted, folded, rolled and cut to fit any space without losing any of its energy. The paper battery can also be stacked to boost the total power output.

How it is made To create this paper we have to first dissolve the cellulose in the ionic liquid and then infiltrate the cellulose paper with aligned carbon nanotubes which form the uniform film. Then it is solidified on dry ice, after this it is soaked in ethonal to remove the ionic liquid and dried in a vacume, which gives us our final product: Nanocomposite paper.

BLOCK D IAGRAM

A paper battery is a flexible, ultra-thin energy storage and production device formed by combining carbon nanotube s with a conventional sheet of cellulose-based paper.nanotube A paper battery acts as both a high-energy battery and super capacitor, combining two components that are separate in traditional electronics.batterysuper capacitorelectronics This combination allows the battery to provide both long-term, steady power production and bursts of energy. Non-toxic, flexible paper batteries have the potential to power the next generation of electronics, medical devices and hybrid vehicles, allowing for radical new designs and medical technologies. Paper battery:

WHAT IS A CARBON NANOTUBE? A carbon nanotube is a tube-shaped material, made of carbon, having a diameter measuring on the nanometer scale. A nanometer is one billionth of the meter or about one ten-thousandth the thickness of the human hair. The graphite layer appears somewhat like a rolled- up chicken wire with a continuous unbroken hexagonal mesh and carbon molecules at the apexes of the hexagons. Carbon Nanotubes have many structures, differing in length, thickness, and in the type of helicity and number of layers. Although they are formed from essentially the same graphite sheet, their electrical characteristics differ depending on these variations, acting either as metals or as semiconductors.

As a group, Carbon Nanotubes typically have diameters ranging from <1 nm up to 50 nm. Their lengths are typically several microns, but recent advancements have made the nanotubes much longer, and measured in centimeters.. They are among the stiffest and strongest fibers known, and have remarkable electronic properties and many other unique characteristics. Carbon Nanotubes can be categorized by their structures: Single-wall Nanotubes (SWNT) Multi-wall Nanotubes (MWNT) Double-wall Nanotubes (DWNT)

How Does Nanocyl Produce Carbon Nanotubes? Nanocyl uses the "Catalytic Carbon Vapour Deposition" method for producing Carbon Nanotube Technologies. It involves growing nanotubes on substrates, thus enabling uniform, large-scale production of the highest-quality carbon nanotubes worldwide. This proven industrial process is well known for its reliability and scalability.

What are the Properties of a Carbon Nanotube? The intrinsic mechanical and transport properties of Carbon Nanotubes make them the ultimate carbon fibers. The following tables compare these properties to other engineering materials. Mechanical properties of engineering fibers are: Fiber material Specific density EnergyStrengthStrain at break(%) Carbon nanotube 1.3 to 2110 to 6010 Carbon fiber-PAN 1.7 to 20.2 to to 50.3 to2.4 Carbon fiber-PITCH 2 to to to to 0.6 Glass / / Kelvar* to Steel <10

Transport properties of conductive materials are: MaterialThermal conductivity (w/mk) Electrical conductivity Carbon nanotube > to 107 Copper 4006*107 Carbon fiber-PITCH to 8.5*106 Carbon fiber-PAN 8 to to 14*106 Overall, Carbon Nanotubes show a unique combination of stiffness, strength, and tenacity compared to other fiber materials which usually lack one or more of these properties. Thermal and electrical conductivity are also very high, and comparable to other conductive materials.

At Stanford, nanotubes + ink + paper = instant battery Dip an ordinary piece of paper into ink infused with carbon nanotubes and silver nanowires, and it turns into a battery or super capacitor. Crumple the piece of paper, and it still works. This is new way of storing electricity. Paper battery is the one that holds promise for new types of lightweight, high-performance energy storage. ordinary paper could one day be used as a lightweight battery to power the devices that are now enabling the printed world to be eclipsed by , e-books and online news.

While a conventional battery contains a number of separate components, the paper battery integrates all of the battery components in a single structure, making it more energy efficient, Integrated devices. "The warm up time, power loss, component malfunction; you don't get those problems with integrated devices. When you transfer power from one component to another you lose energy. But you lose less energy in an integrated device." You can implant a piece of paper in the body and blood would serve as an electrolyte. The battery contains carbon nanotubes, each about one millionth of a centimeter thick, which act as an electrode. The nanotubes are embedded in a sheet of paper soaked in ionic liquid electrolytes, which conduct the electricity.. How a paper battery works?

Electricity is the flow of electrical power or electrons Batteries produce electrons through a chemical reaction between electrolyte and metal in the traditional battery. Chemical reaction in the paper battery is between electrolyte and carbon nanotubes. Electrons collect on the negative terminal of the battery and flow along a connected wire to the positive terminal. Electrons must flow from the negative to the positive terminal for the chemical reaction to continue.

The flexible battery can function even if it is rolled up, folded or cut. Although the power output is currently modest, increasing the output is easy. "If we stack 500 sheets together in a ream, that's 500 times the voltage. If we rip the paper in half we cut power by 50%. So we can control the power and voltage issue." Because the battery consists mainly of paper and carbon, it could be used to power pacemakers within the body where conventional batteries pose a toxic threat. “We wouldn't want the ionic liquid electrolytes in our body, but it works without them that is we can implant a piece of paper in the body and blood would serve as an electrolyte."

EXAMPLE: Let us take an example how the ionic liquid is used as an electrolyte for the paper batteries. As the ionic liquid does not contain any water, there will be nothing to evaporate and the use of ionic liquid in making paper batteries makes the battery to withstand at extreme temperatures. Let us see how the sulphuric acid acts as an electrolyte by studying its properties. Sulphuric acid or sulfuric acid is a strong mineral acid with the molecular formula H2SO4. Its historical name is vitriol. It is soluble in water at all concentrations. It has many applications and is a basic substance in the chemical industry. Polarity and conductivity of H2SO4: H2SO4 is a very polar liquid, having a dielectric constant of around 100. It has a high electrical conductivity caused by dissociation through protonating itself, a process known as autopyrolysis.

Physical properties: Mass fraction H2SO4(%) Density kg/LConcentration mol/L Common name ~1Dilute H2SO4 29 to to to 5Battery acid used in lead acid batteries 62 to to to 11.5Chamber acid Fertilizer acid 78 to to to 14Tower acid Glover acid 95 to ~18Conc. H2SO4

Chemical properties: Reaction with water: The hydration reaction of sulfuric acid is highly exothermic. One should always add the acid to the water rather than the water to the acid. Because the reaction is in an equilibrium that favors the rapid protonation of water, addition of acid to the water ensures that the acid is the limiting reagent. This reaction is best thought of as the formation of hydronium ions: H2SO4 + H2O → H3O+ + HSO4− HSO4− + H2O → H3O+ + SO42− Because the hydration of sulfuric acid is thermodynamically favorable, sulfuric acid is an excellent dehydrating agent.

Reaction with others : Concentrated sulfuric acid reacts with sodium chloride, and gives hydrogen chloride gas and sodium bisulfate: NaCl + H2SO4 → NaHSO4 + HCl Dilute H2SO4 attacks iron, aluminium, zinc, manganese, magnesium and nickel, but reactions with tin and copper require the acid to be hot and concentrated. Lead and tungsten, however, are resistant to sulfuric acid. The reaction with iron shown below is typical for most of these metals, but the reaction with tin produces sulfur dioxide rather than hydrogen. Fe (s) + H2SO4 (aq) → H2 (g) + FeSO4 (aq) Sn (s) + 2 H2SO4 (aq) → SnSO4 (aq) + 2 H2O (l) + SO2 (g) These reactions may be taken as typical: the hot concentrated acid generally acts as an oxidizing agent whereas the dilute acid acts a typical acid. Hence hot concentrated acid reacts with tin, zinc and copper to produce the salt, water and sulfur dioxide, whereas the dilute acid reacts with metals high in the reactivity series to produce a salt and hydrogen.

Concentrated sulfuric acid has a very strong affinity for water. It is sometimes used as a drying agent and can be used to dehydrate (chemically remove water from) many compounds, e.g., carbohydrates. When the concentrated acid mixes with water, large amounts of heat are released. Dilute sulfuric acid is a strong acid and a good electrolyte; it is highly ionized, much of the heat released in dilution coming from hydration of the hydrogen ions. The dilute acid has most of the properties of common strong acids. It turns blue litmus red. It reacts with many metals (e.g., with zinc), releasing hydrogen gas, H2, and forming the sulfate of the metal. It reacts with most hydroxides and oxides, with some carbonates and sulfides, and with some salts. Since it is dibasic (i.e., it has two replaceable hydrogen atoms in each molecule). The Fe3+ produced can be precipitated as the hydroxide or hydrous oxide:hydroxidehydrous oxide Fe3+ (aq) + 3 H2O → Fe(OH)3 (s) + 3 H+

Summary: In case of the lead-acid batteries, the RAYON serves as an electrolyte. But the rayon is made with sulphuric acid. It contains 33% of H2SO4 and with specific gravity 1.25, and is commonly called battery acid. As the sulphuric acid is a strong acid and a good electrolyte, it acts a one of the electrolytes in the manufacture of the paper batteries. Due to its better properties that is physical and chemical properties and the reactions with water and with other reagents, keeping all this in consideration, the sulphuric acid is used as one of electrolytes of the paper battery. Thus in case of other ionic liquid also, we must consider all these properties, to make it use for the purpose of making paper batteries

uses  The paper battery combined with the structure of the nanotubes embedded within gives them their light weight and low cost, making them attractive for portable electronics, aircraft, automobiles and toys (such as model aircraft), medical devices such as pacemakers.  The medical uses are particularly attractive because they do not contain any toxic materials and can be biodegradable, a major drawback of chemical cells.  However, there is a caution that commercial applications may be a long way away, because nanotubes are still relatively expensive to fabricate. Currently, they are making devices a few inches in size.  In order to be commercially viable, they would like to be able to make them newspaper size, a size which taken all together would be powerful enough to power a car.

Applications Cosmetic path: paper battery is set in iontophoresis patch for whitening and wrinkles. Medical path: paper battery is set in iontophoresis patch. It helps to deliver functional drug i.e., local anesthesia, antichloristic, anodyne, etc.. Into skin. RFID tag: paper battery is useful to use as a power source of active RFID tag. Functional card: paper battery is possible to use as a power source of melody and display card. Micro processor; paper battery supply power to micro processor.

Paper battery offers future power  The black piece of paper can power a small light.  Flexible paper batteries could meet the energy demands of the next generation of gadgets.  The ambition is to produce reams of paper that could one day power a car.  The paper battery was a glimpse into the future of power storage.  The versatile paper, which stores energy like a conventional battery, can also double as a capacitor capable of releasing sudden energy Bursts for high-power applications.

CONCLUSION This energy storage device is cost-effective because the device can be able to be used in the smallest and most diversly designed electronics. Such as cell phones, mp3 players and medical equipment. The reasearchers say that it can also be used in automobiles and aircraft. But it has a poor processibility, being that it is particularly insoluble of infuseble. Lastly, the use of ionic liquid makes the device environmentally friendly; a major concern in nanotechnology.

Finally, an interesting idea... Background: battery research results in annual capacity gains of approximately 6% Moore’s Law: The number of transistors on a computer microchip will double every two years. (40 years of proof!) Idea: If battery technology had developed at the same rate, a heavy duty car battery would be the size of a penny.

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