Paper Battery Full Seminar Report on Www Way2project In

ABSTRACT

The Batteries form a significant

part of many electronic devices. Typical

electrochemical batteries or cells convert

chemical energy into electrical energy.

Batteries based on the charging ability

are classified into primary and secondary

cells. Secondary cells are widely used

because of their rechargeable nature.

Presently, battery takes up a huge

amount of space and contributes to a

large part of the device's weight. There is

strong recent interest in ultrathin,

flexible, safe energy storage devices to

meet the various design and power needs

of modern gadgets. New research

suggests that carbon nanotubes may

eventually provide the best hope of

implementing the flexible batteries

which can shrink our gadgets even more.

The paper batteries could meet the

energy demands of the next generation

gadgets. A paper battery is a flexible,

ultra-thin energy storage and production

device formed by combining carbon

nanotubes with a conventional sheet of

cellulose-based paper. A paper battery

acts as both a high-energy battery and

super capacitor, combining two

components that are separate in

traditional electronics. 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.

The various types of batteries followed

by the operation principle,

manufacturing and working of paper

batteries are discussed in detail.

Keywords: paper batteries, flexible,

carbon nanotubes

INTRODUCTION TO

BATTERIES

An electrical battery is one or more

electrochemical cells that convert stored

chemical energy into electrical energy.

Since the invention of the first battery in

1800 by Alessandro Volta, batteries have

become a common power source for

many household and industrial

applications.

Batteries are represented symbolically as

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Fig. 1a Symbolic view

Fig. 1b conventional battery

Electrons flow from the negative

terminal towards the positive terminal.

Based on the rechargeable nature

batteries are classified as

a. Non rechargeable or

primary cells

b. Rechargeable or

secondary cells

Based on the size they are classified as

a. Miniature batteries

b. Industrial batteries

Based on nature of electrolyte

a. Dry cell

b. Wet cell

Terminologies

1. Accumulator - A rechargeable

battery or cell

2. Ampere-Hour Capacity - The

number of ampere-hours which

can be delivered by a battery on a

single discharge.

3. Anode - During discharge, the

negative electrode of the cell is

the anode. During charge, that

reverses and the positive

electrode of the cell is the anode.

The anode gives up electrons to

the load circuit and dissolves into

the electrolyte.

4. Battery Capacity - The electric

output of a cell or battery on a

service test delivered before the

cell reaches a specified final

electrical condition and may be

expressed in ampere-hours, watt-

hours, or similar units. The

capacity in watt-hours is equal to

the capacity in ampere-hours

multiplied by the battery voltage.

5. Cutoff Voltage final - The

prescribed lower-limit voltage at

which battery discharge is

considered complete. The cutoff

or final voltage is usually chosen

so that the maximum useful

capacity of the battery is realized.

6. C - Used to signify a charge or

discharge rate equal to the

capacity of a battery divided by 1

hour. Thus C for a 1600 mAh

battery would be 1.6 A, C/5 for

2

the same battery would be 320

mA and C/10 would be 160 mA.

7. Capacity - The capacity of a

battery is a measure of the

amount of energy that it can

deliver in a single discharge.

Battery capacity is normally

listed as amp-hours (or milli

amp-hours) or as watt-hours.

8. Cathode - Is an electrode that,

in effect, oxidizes the anode or

absorbs the electrons. During

discharge, the positive electrode

of a voltaic cell is the cathode.

When charging, that reverses and

the negative electrode of the cell

is the cathode.

9. Cycle - One sequence of

charge and discharge.

10. Cycle Life - For

rechargeable batteries, the total

number of charge/discharge

cycles the cell can sustain before

its capacity is significantly

reduced. End of life is usually

considered to be reached when

the cell or battery delivers only

80% of rated ampere- hour

capacity.

11. Electrochemical

Couple - The system of active

materials within a cell that

provides electrical energy storage

through an electrochemical

reaction.

12. Electrode - An

electrical conductor through

which an electric current enters

or leaves a conducting medium

13. Electrolyte - A

chemical compound which, when

fused or dissolved in certain

solvents, usually water, will

conduct an electric current.

14. Internal Resistance -

The resistance to the flow of an

electric current within the cell or

battery.

15. Open-Circuit Voltage

- The difference in potential

between the terminals of a cell

when the circuit is open (i.e., a

no-load condition).

16. Voltage, cutoff -

Voltage at the end of useful

discharge. (See Voltage, end-

point.)

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17. Voltage, end-point -

Cell voltage below which the

connected equipment will not

operate or below which operation

is not recommended.

Principal of Operation of

cell

A battery is a device that converts

chemical energy directly to electrical

energy. It consists of a number of voltaic

cells. Each voltaic cell consists of two

half cells connected in series by a

conductive electrolyte containing anions

and cations. One half-cell includes

electrolyte and the electrode to which

anions (negatively charged ions)

migrate, i.e., the anode or negative

electrode. The other half-cell includes

electrolyte and the electrode to which

cations (positively charged ions)

migrate, i.e., the cathode or positive

electrode. In the redox reaction that

powers the battery, cations are reduced

(electrons are added) at the cathode,

while anions are oxidized (electrons are

removed) at the anode. The electrodes do

not touch each other but are electrically

connected by the electrolyte. Some cells

use two half-cells with different

electrolytes. A separator between half

cells allows ions to flow, but prevents

mixing of the electrolytes.

Fig.

1.2 principle operation

Each half cell has an electromotive force

(or emf), determined by its ability to

drive electric current from the interior to

the exterior of the cell. The voltage

developed across a cell's terminals

depends on the energy release of the

chemical reactions of its electrodes and

electrolyte. Alkaline and carbon-zinc

cells have different chemistries but

approximately the same emf of 1.5 volts.

Likewise NiCd and NiMH cells have

different chemistries, but approximately

the same emf of 1.2 volts. On the other

hand the high electrochemical potential

changes in the reactions of lithium

compounds give lithium cells emf of 3

volts or more.

Types of batteries

Batteries are classified into two broad

categories. Primary batteries irreversibly

(within limits of practicality) transform

chemical energy to electrical energy.

When the initial supply of reactants is

exhausted, energy cannot be readily

restored to the battery by electrical

means. Secondary batteries can be

recharged. That is, they can have their

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chemical reactions reversed by supplying

electrical energy to the cell, restoring

their original composition.

Primary batteries: This can produce

current immediately on assembly.

Disposable batteries are intended to be

used once and discarded. These are most

commonly used in portable devices that

have low current drain, are only used

intermittently, or are used well away

from an alternative power source, such

as in alarm and communication circuits

where other electric power is only

intermittently available. Disposable

primary cells cannot be reliably

recharged, since the chemical reactions

are not easily reversible and active

materials may not return to their original

forms. Battery manufacturers

recommend against attempting

recharging primary cells. Common

types of disposable batteries include

zinc-carbon batteries and alkaline

batteries.

Secondary batteries: These batteries

must be charged before use. They are

usually assembled with active materials

in the discharged state. Rechargeable

batteries or secondary cells can be

recharged by applying electric current,

which reverses the chemical reactions

that occur during its use. Devices to

supply the appropriate current are called

chargers or rechargers.

Fig. 1.3a Primary cell

Fig. 1.3b Secondary cell

Recent developments

Recent developments include

batteries with embedded functionality

such as USBCELL, with a built-in

charger and USB connector within the

AA format, enabling the battery to be

charged by plugging into a USB port

without a charger USB Cell is the brand

of NiMH rechargeable battery produced

by a company called Moixa Energy. The

batteries include a USB connector to

allow recharging using a powered USB

port. The product range currently

available is limited to a 1300 mAh.

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Fig. 1.4 USB cell

Life of battery

Even if never taken out of the original

package, disposable (or "primary")

batteries can lose 8 to 20 percent of their

original charge every year at a

temperature of about 20°–30°C. [54]

This is known as the "self-discharge"

rate and is due to non-current-

producing "side" chemical reactions, which occur within the cell even if no

load is applied to it. The rate of the side

reactions is reduced if the batteries are

stored at low temperature, although

some batteries can be damaged by

freezing. High or low temperatures may

reduce battery performance. This will

affect the initial voltage of the battery.

For an AA alkaline battery this initial

voltage is approximately normally

distributed around 1.6 volts.

Rechargeable batteries self-discharge

more rapidly than disposable alkaline

batteries, especially nickel-based

batteries a freshly charged NiCd loses

10% of its charge in the first 24 hours,

and thereafter discharges at a rate of

about 10% a month. Most nickel-

based batteries are partially discharged

when purchased, and must be charged

before first use.

Hazards related to batteries

Explosion

A battery explosion is caused by the

misuse or malfunction of a battery, such

as attempting to

recharge a primary

(non-rechargeable)

battery, or short

circuiting a battery.

Corrosion

Many battery chemicals are corrosive,

poisonous, or both. If leakage occurs,

either spontaneously or through accident,

the chemicals released may be dangerous

Environmental pollution

The widespread use of batteries has

created many environmental concerns,

such as toxic metal pollution. Battery

manufacture consumes resources and

often involves hazardous chemicals.

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Fig 1.5 Life cycle

Used batteries also contribute to

electronic waste.

Americans purchase nearly three billion

batteries annually, and about 179,000

tons of those end up in landfills across

the country.

Ingestion

Small button/disk batteries can be

swallowed by young children. While in

the digestive tract the battery's electrical

discharge can burn the tissues and can be

serious enough to lead to death.

Fig 1.6 Electronic waste

PAPER BATTERY

Energy has always been spotlighted. In

the past few years a lot of inventions

have been made in this particular field.

The tiny nuclear batteries that can

provide energy for 10 years, but they use

radioactive elements and are quite

expensive. Few years back some

researchers from Stanford University

started experiments concerning the ways

in which a copier paper could be used as

a battery source. After a long way of

struggle they, recently, concluded that

the idea was right. The batteries made

from a plain copier paper could make for

the future energy storage that is truly

thin.

The anatomy of paper battery is based on

the use of Carbon Nanotubes tiny

cylinders to collect electric charge. The

paper is dipped in lithium containing

solution. The nanotubes will act as

electrodes allowing storage device to

conduct electricity. It’s astounding to

know that all the components of a

conventional battery are integrated in a

single paper structure; hence the

complete mechanism for a battery is

minimized to a size of paper.

One of the many reasons behind

choosing the paper as a medium for

battery is the well-designed structure of

millions of interconnected fibers in it.

These fibers can hold on carbon

nanotubes easily. Also a paper has the

capability to bent or curl.

You can fold it in different shapes

and forms plus it as light as feather.

Output voltage is modest but it could be

increased if we use a stack of papers.

Hence the voltage issues can be easily

controlled without difficulty. Usage of

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paper as a battery will ultimately lead to

weight diminution of batteries many

times as compared to traditional

batteries.

It is said that the paper battery also has

the capability of releasing the energy

quickly. That makes it best utilization for

devices that needs burst of energy,

mostly electric vehicles. Further, the

medical uses are particularly attractive

because they do not contain any toxic

materials.

Fig.2 paper battery

CARBON NANOTUBES

Carbon nanotubes (CNTs) are allotropes

of carbon with a cylindrical

nanostructure. Nanotubes have been

constructed with length-to-diameter ratio

of up to 132,000,000:1, significantly

larger than any other material. These

cylindrical carbon molecules have novel

properties, making them potentially

useful in many applications in

nanotechnology, electronics, optics, and

other fields of materials science, as well

as potential uses in architectural fields.

They may also have applications in the

construction of body armor. They exhibit

extraordinary strength and unique

electrical properties, and are efficient

thermal conductors.

Their name is derived from their size,

since the diameter of a nanotube is on

the order of a few nanometers

(approximately 1/50,000th of the width

of a human hair), while they can be up to

18 centimeters in length (as of 2010).

Nanotubes are categorized as single-

walled nanotubes (SWNTs) and multi-

walled nanotubes (MWNTs).

In theory, metallic nanotubes can carry

an electric current density of 4 × 109

A/cm2 which is more than 1,000 times

greater than metals such as copper,

where for copper interconnects current

densities are limited by electro

migration.

In paper batteries the nanotubes act as

electrodes, allowing the storage devices

to conduct electricity. The battery, which

functions as both a lithium-ion battery

and a super capacitor, can provide a

long, steady power output comparable to

a conventional battery, as well as a super

capacitor’s quick burst of high energy

and while a conventional battery

contains a number of separate

components, the paper battery integrates

all of the battery components in a single

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structure, making it more energy

efficient.

Carbon nanotubes have been

implemented in Nano electromechnical

systems, including mechanical memory

elements(NRAM being developed by

Nantero Inc.)

Fig 3. Carbon nanotubes

FABRICATION OF PAPER

BATTERY

The materials required for the

preparation of paper battery are

a. Copier paper

b. Carbon nano ink

c. Oven

The steps involved in the preparation of

the paper battery are as follows

Step 1: The copier paper is taken.

Step 2: carbon Nano ink which is black

in color is taken. Carbon nano ink is a

solution of nano rods, surface adhesive

agent and ionic salt solutions. Carbon

nano ink is spread on one side of the

paper.

Step 3: the paper is kept inside the oven

at 150C temperature. This evaporates the

water content on the paper. The paper

and the nano rods get attached to each

other.

Step 4: place the multi meter on the sides

of the paper and we can see voltage drop

is generated.

Fig 4. Fabrication process

After drying the paper becomes flexible,

light weight in nature. The paper is

scratched and rolled to protect the nano

rods on paper.

WORKING OF PAPER

BATTERY

The battery produces electricity in the

same way as the conventional lithium-

ion batteries that power so many of

today's gadgets, but all the components

have been incorporated into a

lightweight, flexible sheet of paper.

The devices are formed by combining

cellulose with an infusion of aligned 9

carbon nanotubes. The carbon is what

gives the batteries their black color.

These tiny filaments act like the

electrodes found in a traditional battery,

conducting electricity when the paper

comes into contact with an ionic liquid

solution.

Ionic liquids contain no water, which

means that there is nothing to freeze or

evaporate in extreme environmental

conditions. As a result, paper batteries

can function between -75 and 1500C.

The paper is made conducting material

by dipping in ink. The paper works as a

conductive layer. Two sheets of paper

kept facing inward act like parallel plates

(high energy electrodes). It can store

energy like a super capacitor and it can

discharge bursts of energy because of

large surface area of nano tubes.

Fig.5 working of a paper battery

Chlorine ions flow from the positive

electrode to the negative one, while

electrons travel through the external

circuit, providing current. The paper

electrode stores charge while recharging

in tens of seconds because ions flow

through the thin electrode quickly. In

contrast, lithium batteries take 20

minutes to recharge.

ADVANTAGES

The flexible shape allows

the paper battery to be used small

or irregularly-shaped electronics:

One of the unique features of the paper

battery is that it can be bent to any such

shape or design that the user might have

in mind. The battery can easily squeeze

into tight crevasses and can be cut

multiple times without ruining the

battery's life. For example if a battery is

cut in half, each piece will function,

however, each piece will only contain

1/2 the amount of original power.

Conversely, placing two sheets of paper

battery on top of one-another will double

the power.

The paper battery may

replace conventional batteries

completely:

By layering sheets of this paper, the

battery's voltage and current can be

increased that many times. Since the

main components of the paper battery

are carbon nanotubes and cellulose, the

body structure of the battery is very thin,

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"paper-thin". Thus to maximize even

more power, the sheets of battery paper

can be stacked on top of one another to

give off tremendous power. This can

allow the battery to have a much higher

amount of power for the same size of

storage as a current battery and also be

environmentally friendly at the same

time.

Supply power to an

implanted pacemaker in the

human body by using the

electrolytes in human blood:

An improvement in the techniques used

in the health field can be aided by the

paper battery. Experiments have taken

place showing that batteries can be

energized by the electrolyte emitted from

one's own blood or body sweat. This can

conserve the usage of battery acid and

rely on an environmental friendly

mechanism of fueling battery cells with

the help from our bodies.

The paper battery can be

molded to take the shape of large

objects, like a car door:

As stated earlier, the key characteristics

that make the paper battery very

appealing are that it can be transformed

into any shape or size, it can be cut

multiple times without damaging it, and

it can be fueled through various ways

besides the typical harmful battery acid

that is used in the current day battery.

LIMITATIONS

• Presently, the devices are only a

few inches across and they have to be

scaled up to sheets of newspaper size to

make it commercially viable.

• Carbon nanotubes are very

expensive, and batteries with large

enough power are unlikely to be cost

effective.

• Cutting of trees leading to destroying

of the nature.

APPLICATIONS

Pace makers in heart

(uses blood as electrolyte)

Used as alternate to

conventional batteries in gadgets

Powered smart cards RF

id tags

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Smart toys, children

sound books

E-cards, greetings, talking

posters

Girls/boys’ apparel

CONCLUSION

We have discussed the various

terminologies, principle of operation of a

battery and recent developments related

to it. The life of a battery is an important

parameter which decides the area of

application of the battery. Increased use

of batteries gives rise to E-waste which

poses great damage to our environment.

In the year 2007 paper battery

was manufactured. The technology is

capable of replacing old bulky batteries.

The paper batteries can further reduce

the weight of the electronic gadgets.

The adaptations to the paper

battery technique in the future could

allow for simply painting the nanotube

ink and active materials onto surfaces

such as walls. These surfaces can

produce energy.

REFERENCES

Thin, Flexible Secondary

Li-Ion Paper Batteries Liangbing

Hu, Hui Wu, Fabio La Mantia,

Yuan Yang, and Yi Cui

Department of Materials Science

and Engineering, Stanford

University, Stanford, California

94305.

David Linden “Handbook

of batteries”

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