Paper battery report.docx

ANALYSIS OF PAPER BATTERIES
Dept of EEE, VVCE MYSORE Page 1
CHAPTER – 1
INTRODUCTION
1.1 INTRODUCTION TO ORDINARY BATTERY
All battery contains one or more cells, but people often use the terms battery and cell
interchangeably. A cell is just the working chemical unit inside a battery; one battery can contain
any number of cells. A cell has three main parts: a positive electrode (terminal), a negative
electrode, and a liquid or solid separating them called the electrolyte. When a battery is
connected to an electric circuit, a chemical reaction takes place in the electrolyte
causing ions (in this case, atoms with a positive electrical charge) to flow through it one way,
with electrons (particles with a negative charge) flowing through the outer circuit in the other
direction. This movement of electric charge makes an electric current flow through the cell and
through the circuit it is connected to. It's important to note that the electrodes in a battery
are always made from two dissimilar materials (so never both from the same metal, for
example). This is the key to how and why a battery works: one of the materials "likes" to give up
electrons, the other likes to receive them. If both electrodes were made from the same material,
that wouldn't happen and no current would flow.
Figure 1.1.1 Ordinary battery
When you connect the battery to a lamp and switch on, chemical reactions start happening. One
of the reactions generates positive ions (shown here as big yellow blobs) and electrons (smaller
brown blobs) at the negative electrode. The positive ions flow through the electrolyte to the
positive electrode (from the green line to the red one). Meanwhile, the electrons (smaller brown
blobs) flow around the outside circuit (blue line) to the positive electrode and make the lamp
light up on the way.
The electrons and ions flow because of the chemical reactions happening inside the battery—
usually two or three of them going on simultaneously. The exact reactions depend on the

materials from which the electrodes and electrolyte are made, and we won't go into them here. (If
you want to know what they are, enter the type of the battery you're interested in followed by the
words "anode cathode reactions" in your favorite search engine.) Whatever chemical reactions
take place, the general principle of electrons going around the outer circuit and ions’ flowing in
the opposite direction through the electrolyte happens in all batteries. As the battery generates
power, the chemicals inside it are gradually converted into different chemicals. Their ability to
generate power dwindles, the battery's voltage slowly falls, and the battery eventually runs flat.
In other words, if the battery cannot produce positive ions because the chemicals inside it have
become depleted, it can't produce electrons for the outer circuit either.
1.2 NEED FOR PAPER BATTERIES :
The basic problems associated with the present Electro-Chemical batteries are:
(1) Limited Life- Time: Primary batteries irreversibly (within limits of practicality) transform
chemical energy to electrical energy. Secondary batteries can be recharged; that is, they can
have their chemical reactions reversed by supplying electrical energy to the cell, restoring their
original composition. But, Rechargeable batteries are still costlier than Primary Batteries in the
markets of developing countries like India.
(2) Leakage: If leakage occurs, either spontaneously or through accident, the chemicals released
may be dangerous. For example, disposable batteries often use zinc "can" as both a reactant
and as the container to hold the other reagents. If this kind of battery is run all the way down,
or if it is recharged after running down too far, the reagents can emerge through the
cardboard and plastic that forms the remainder of the container. The active chemical leakage
can then damage the equipment that the batteries were inserted into.
(3)Environmental Concerns: The widespread use of batteries has created many environmental
concerns, such as toxic metal pollution. Metals such as Cadmium, Mercury, Lead, Lithium and
Zinc have been identified as highly toxic metals. Also, batteries may be harmful or fatal if
swallowed. 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.
Figure 1.2.1 A Leaking Electrochemical Battery

The limitations of Fuel cells are:
(1). Cost: Hydrogen-based fuel cells are still extremely costly for general consumer use. Their
use is still restricted to rocket launch vehicles. Liquid Hydrogen and Hydrogen Peroxide are
essential ingredients that make them costly.
(2). Portability & Size: Fuel cells are still not portable in size, which makes it very difficult
for use in electronic and medical gadgets.
The limitations of Solar Cells are:
(1) Versatility: Solar cells can not be used under all situations, like Emergency Power-Backup,
Emergency Energy Purge.
(2) Adaptability: Solar cells can not be used in all battery-powered equipment.
(3). Portability & Size: They are not at all portable or robust.
(4)Need of an Auxiliary back-up battery: The solar cells need an auxiliary back-up
battery during failures.
1.3 INTRODUCTION OF PAPER BATTERY
A paper battery is a flexible, ultra thin energy storage device. It can act as a super capacitor and
also as a high – energy battery, combining two discrete components that are separate in
traditional electronics. The functioning of paper batteries is similar to that of a normal chemical
battery. In normal cases, conventional batteries may be easily damaged by corrosion and also
sometimes they required a bulky housing. But the paper batteries are non-corrosive, non-toxic
and light-weight than the normal batteries. It is created by combining two things: nano composite
paper and nanotubes (nano composite paper made from cellulose and nanotubes made from
carbon). Nanocomposite paper is a hybrid energy storage device made of cellulose, which
combines the features of super capacitors and batteries. It takes the high-energy storage capacity
of the battery and high-energy density of the super capacitor producing the bursts of extreme
power.
Paper Battery= Paper (Cellulose) + Carbon Nanotubes
This combination permits the battery to provide both long term, bursts of energy, steady power
and production. Paper batteries have the potential to power the next generation of medical
devices, electronics and hybrid vehicles. Paper batteries can be folded, twisted, molded,
crumpled, shaped and cut for various applications without any loss of efficiency, cutting one in
half halves its energy production. Stacking them multiplies power output. Early prototypes of the
device are able to produce 2.5 volts of electricity from a sample the size of a postage stamp.

The paper batteries are formed by combining cellulose with an infusion of aligned carbon
nanotubes that are each approximately one millionth of a centimeter thick. 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 150 degrees Celsius.
Fig 1.3.1 Paper battery
1.3.1 PAPER BATTERY PROPERTIES :
Paper battery properties are mainly attributed to the properties of its parts such as cellulose and
carbon nanotubes.
Cellulose is a long chain of linked sugar molecules that gives wood its remarkable strength. It is
the main component of plant cell walls, and the basic building block for many textiles and for
paper. The properties of Cellulose include high-tensile strength, biodegradability, low-shear
Strength, biocompatibility, good absorption capacity and excellent Porosity, non-toxic,
reusability & recyclability.
Carbon is accomplished with many allotropes. Some renowned form of carbon allotropes are
diamonds, graphite etc. Currently different forms of allotropes of carbon have been ascertained
and researched like carbon nanotubes. In Carbon nanotubes, each carbon atom is amalgamating
with all other three carbon atoms in order to form a nanosize cylindrical structure. The nanosize
cylindrical structure along with its novel properties makes the carbon nanotube conceivably
beneficial in wide range of applications in materials science, electronics, nanotechnology and
optics. The carbon nanotube unveils outstanding strength along with its distinctive electrical
properties also the carbon nanotube is an effective heat conductor too

Figure 1.3.2 Carbon nanotubes
Properties of carbon Nanotubes used in construction of paper battery:
Carbon nanotubes are generally regarded as the single hardest materials known to man. A single
walled nanotube is able to withstand a pressure that amounts to 24 GPa. It can withstand this
pressure without having any kind of deformity and without seeming like it is being affected in
anyway. Nanotubes are also known to have kinetic properties that make them get nested with
each other. There is an outstanding telescoping property that they tend to display with time and
this usually involves sliding of the inner core nanotube. This sliding occurs with very little or no
friction at all and usually leads to rotational bearing.
When dealing with carbon nanotubes it is very vital to know that their electrical properties are
very unique. The nanotube structure usually has an effect on the electrical properties of
graphene owing to its electronic structure that is quite unique. There are however a number of
exceptions in the general rule regarding the electrical properties of these nanotubes. Some
superconductivity properties have also been registered with some of these nanotubes and
although there are several other experiments that disagree with this assertion, these reports
continue to create a stir among experts.
The thermal properties of carbon nanotubes are quite unique too because these nanotubes are
mostly expected to have good conduction. Ballistic conduction is actually a property that is
shown by the nanotubes as they go about their thermal conduction. Another vital issue in the
properties of these nanotubes is the issue of toxicity. When dealing with nanotechnology, many
experts have raised several questions about the toxicity of the nanotubes. This study and
research is still in its early stages and there is quite a lot criticism still going on. It is expected
that over the years the results will help to give experts a little more understanding of how these
nanotubes deal with the question of toxicity.

CHAPTER – 2
CONSTRUCTION OF PAPER BATTERY
A paper battery construction involves the following components:
 Cathode: Carbon Nanotube (CNT)
 Anode: Lithium metal (Li+)
 Electrolyte: All electrolytes (including bio Electrolytes like sweat, blood and urine)
 Separator: Paper (Cellulose).
Actually, there are many ways to construct paper batteries
The first and foremost method of constructing paper batteries was proposed and initiated by
Robert Linhardt, a chemist at Rensselaer Polytechnic Institute in Troy, New York. Cellulose
(paper) was layered upon conductive carbon nanotubes. Though the combination would be a
sturdy material to construct batteries, however problem arose when the materials would fall apart
when flexed. A solution was found by Yi Cui, a materials scientist at Stanford University, Palo
Alto (California).
He and his team of researchers created an ink of carbon nanotube by suspending them in water
and an organic surfactant. This ink was evenly spread on a piece of paper. As the inked paper
was heated in the oven to drive off the water, the nanotubes bonded tightly to the paper fibers
and a highly conductive sheet of paper were created.
Given below are three ways to create paper batteries:
1. The first method involves fabricating zinc and manganese dioxide based cathode and anode.
The batteries are printed onto paper using standard silkscreen printing press.
This paper is infused with aligned carbon nanotubes which are used as electrode. This paper is
dipped in a solution of ionic liquid which acts as the electrolyte.
2. The second method is a bit complex and involves growing nanotubes on a silicon substrate.
The gaps in the matrix are then filled with cellulose and once the matrix is dried, the
combination of cellulose and nanotubes is peeled off. Thus sheets of paper consisting of layers
of carbon nanotubes are created. Two such sheets are combined together to form a super
capacitor with a ionic liquid like human blood, sweat or urine being used an electrolyte.

3. The third is a simple method and can be constructed in a laboratory. It involves spreading
specially formulated ink of carbon nanutubes over a rectangular sheet of paper coated with an
ionic solution. A thin film of lithium is then laminated on the other side of the paper. Aluminium
rods are then connected to carry current between the two electrodes.
Figure 2.1 Paper Battery Parts
4. The fourth method involves coating substrate of stainless steel with carbon nanotubes. The
coated substrate is the dried at 80 degree Celsius for five minutes, after which the material is
peeled off. A pair of films are used for each paper battery with each film being pasted to
different electrolytes like LTO and LCO. A paper is then sandwiched between the two film using
glue
Figure 2.2 Paper battery construction process

CHAPTER – 3
WORKING OF PAPER BATTERY
The internal performance of paper batteries is identical to that of a traditional battery by
generating a voltage about 1.5V. We can recall the working principles of a traditional batteries
where ions (+ ve charged particles) and electrons (- ve charged particles) moves between the
electrodes, anode (+ve electrode) and cathode (-ve electrode). Due to the flow of electrons from
cathode to anode, current start flowing from anode to cathode along the conductor.
 Cathode: Carbon Nanotube
 Anode: Lithium metal (Li+)
 Electrolyte: bio electrolytes like urine, blood and sweat. (All electrolytes can be used)
 Separator: Cellulose or Paper
Similarly in Paper Batteries, the metal (Lithium) is used as the anode and carbon nanotubes as
cathode and also the paper or cellulose is used as the separator. Due to the chemical reaction
between the electrolyte and carbon, electrons are generated. Similarly due to the chemical
reaction between electrolyte and metal, ions are generated. These generated electrons starts flow
through the external circuit from cathode to the anode.
A conventional battery or Rechargeable battery contains a number of separate components that
produce electrons through a chemical reaction between the metal and the electrolyte of the
battery. The Paper battery works when the paper is dipped in the ion-based liquid solution; next
a chemical reaction occurs between the electrodes and liquid. The electrons move from the
cathode to anode to generate electricity. The paper electrode stores energy while recharging
within 10 seconds because the ions flow through the thin electrode quickly. The best method to
increase the output of the battery is to stack different paper batteries one over the other.
Figure 3.1 Operation of paper battery

CHAPTER – 4
EXPERIMENTAL DETAILS
The objective of the present work was to explore the possibility of low cost materials like silica
gel, ordinary paper, graphite powder & metallic aluminium paint for the development of
thinner batteries including paper battery. The details are given in table 4.1.
Table 4.1 Details of the materials used in
development of paper battery
Two types of batteries for preliminary investigation have been developed zinc-silica gel-copper
battery & graphite-paper-aluminium battery. The details are given in table 4.2.
Table 4.2 Details of types of batteries developed
for preliminary investigation

4.1 Zinc - Silica gel – Copper battery (Z-S-C battery)
Silica gel is hygroscopic in nature. It has the ability to hold the electrolyte for long. Besides, use
of silica gel can reduce the shedding of active material from the plates. This may increase the
battery-life. It was thought it would help to increase the discharging time of battery. Thus, Zinc-
silica gel-Copper battery was made.
Materials and methods :
Zinc-silica gel-Copper battery was made by adhering layer of silica gel sand witched
between zinc and copper plates. The open circuit voltage of battery is recorded using
multimeter.
Experimental procedure
• The electrolytic solution of citric acid is prepared by adding 2 ml citric acid in 250 ml
water.
• The setup is formed by adhering a layer silica gel between zinc and copper plates.
• The setup is dipped in the citric acid solution for about 30 min and then removed.
• The open circuit voltage (OCV) is measured across the current collectors of the plates
using multimeter.
Figure 4.1.1 Zinc - silica gel - copper battery (Z-S-C battery)

4.2. Graphite powder – Electrolyte (paper) – Aluminium paint Battery
(G-P-A battery)
Efforts have always been made to seek a balance between a battery and a capacitor so as to
utilize the properties of both. So the concept of paper battery was put forth. In this type of
battery, an attempt was made to construct paper battery using low cost materials such as
ordinary paper.
Materials and methods:
Graphite powder – Electrolyte (paper) – Aluminium paint Battery was made using metallic
coatings of graphite powder and aluminium paint on either sides of paper. The fibrous & porous
structure of paper enables to hold and provide free motion to the ions of electrolyte. The open
circuit voltage generated is recorded using multimeter.
Experimental procedure
• The electrolytic solution of vinegar is prepared by adding 10 ml vinegar in 1000 ml water.
• Ordinary copier paper of desired shape and size is taken.
• One side of the paper is coated with graphite powder. Then the paper is allowed to dry at
room temperature for about 10-12 hrs.
• Aluminium paint is coated over the exposed cellulose surface, which completes the
paper battery. This aluminium film acts as anode.
• Finally, the paper battery is connected to the zinc current collectors.
• The setup is dipped in electrolyte for few minutes and taken out.
• With the help of the current collectors, open circuit voltage (OCV) is measured using
multimeter.
• The procedure is repeated by varying size and thickness of paper and also by stacking
the paper sheets together and finally, its effect on OCV is studied
Figure 4.2.1 Graphite powder - electrolyte(paper) – Aluminium painted battery
(G-P-A battery)

CHAPTER – 5
RESULTS AND DISCUSSION
The results can be summarized as follows
1. Zinc – Silica Gel – Copper battery
From experiments conducted, Zn-Silica Gel- Cu battery yielded a maximum OCV of 0.88 volt.
However, the overall results were not so convincing as the OCV was fluctuating & instable.
2. Graphite powder – Electrolyte(paper) – Aluminium paint battery
Graphs are plotted between open circuit voltage as a function of size of paper, thickness of
paper & stacked paper sheets & are shown in figure nos. 5.1 to 5.3
Figure 5.1 Effect of change in size of paper on OCV of battery

Figure 5.2 Effect of change in thickness of paper on OCV of battery
Figure 5.3 Effect of stacking of paper sheets on OCV of battery
It can be observed that these parameters are definitely affecting the open circuit voltage of
battery which can be summarized as follows:
• As the size of paper increases, OCV of battery also increases.
• As the thickness of paper increases, OCV of battery increases
• Stacking of paper sheets increases the discharging time of battery.
A newly developed battery has to undergo certain tests so as to validate its performance
prior to its commercialization. Table 5.1 shows the details of the comparison based on some of
the parameters of paper battery reported in literature, conventional battery & battery
developed in the present work.

Table 5.1 Comparison of present work, paper battery and conventional battery
in terms of evaluation parameters
Figure 5.4 Discharge curves of paper battery and metal casing cell

CHAPTER – 6
ADVANTAGES AND LIMITATIONS
6.1 ADVANTAGES OVER EXISTING BATTERIES:
1. Biodegradable & Non Toxic: Since its major ingredients are of organic origin, it is a
biodegradable and non toxic product.
2. Biocompatible: They are not easily rejected by our body's immune system if implanted
into human body.
3. Easily Reusable & Recyclable: Being cellulose based product it is easily
recyclable and reusable, even with the existing paper recycling techniques.
4. Durable: It has a shelf life of three years (at room temperature). Under extreme
conditions it can operate within -75° to +150°C.
5. Rechargeable: It can be recharged upto 300 times using almost all electrolytes, including
bio-salts such as sweat, urine and blood.
6. No Leakage & Overheating: Owing to low resistance, it does not get overheated even
under extreme conditions. Since there are no leaky fluids, so even under spontaneous or
accidental damage, there is no leakage problem.
7. Very Light Weight & Flexible.
8. Easily Moldable Into Desired Shapes & Sizes.
9. Customizable Output Voltage:
• By varying CNT concentration.
• By stacking & slicing.
. 6.2 LIMTATIONS & DISADVANTAGES OF PAPER
BATTERIES:
It would not be logical only to ponder over the miraculous properties and applications of
Paper Batteries .Things need to be discussed at the flip side as well. Following are some of
them:
• Have Low Shear strength: They can be ‘torn’easily.
• The Techniques and the Set-ups used in the production of Carbon Nanotubes
are very Expensive and very less Efficient. These are:
(i)Arc discharge
(ii)Chemical Vapour Deposition (CVD) (iii) Laser Ablation
(iv)Electrolysis
• When inhaled, their interaction with the Microphages present in the lungs is
similar to that with Asbestos fibers, hence may be seriously hazardous to human health

CHAPTER – 7
APPLICATIONS
7.1 APPLICATIONS
With the developing technologies and reducing cost of CNTs, the paper batteries will find
applications in the following fields:
7.1.1 In Electronics:
• in laptop batteries, mobile phones, handheld digital cameras: The weight of these
devices can be significantly reduced by replacing the alkaline batteries with light-weight
Paper Batteries, without compromising with the power requirement. Moreover, the
electrical hazards related to recharging will be greatly reduced.
• in calculators, wrist watch and other low drain devices.
• in wireless communication devices like speakers, mouse, keyboard ,Bluetooth
headsets etc.
• in Enhanced Printed Circuit Board(PCB) wherein both the sides of the PCB can be
used: one for the circuit and the other side (containing the components )would contain a layer
of customized Paper Battery. This would eliminate heavy step-down transformers and the need
of separate power supply unit for most electronic circuits.
Figure 7.1.1 Applications of paper battery

7.1.2. In Automobiles and Aircrafts:
• in Hybrid Car batteries
• in Long Air Flights reducing Refueling
• for Light weight guided missiles
• for powering electronic devices in Satellite programs
7.1.3 In Medical Sciences:
• in Pacemakers for the heart
• in Artificial tissues (using Carbon nanotubes)
• in Cosmetics, Drug-delivery systems
• in Biosensors, such as Glucose meters, Sugar meters, etc.

CHAPTER – 8
CONCLUSION
One of the major problems bugging the world now is Energy crisis. Every nation needs
energy and everyone needs power. And this problem which disturbs the developed countries
perturbs the developing countries like India to a much greater extent. Standing at a point in
the present where there can’t be a day without power, Paper Batteries can provide an altogether
path-breaking solution to the same. Being Biodegradable, Light-weight and Non- toxic, flexible
paper batteries have potential adaptability to power the next generation of electronics, medical
devices and hybrid vehicles, allowing for radical new designs and medical technologies. But
India still has got a long way to go if it has to be self-dependant for its energy solution.
Literature reflects that Indian researchers have got the scientific astuteness needed for such
revolutionary work. But what hinders their path is the lack of facilities and funding. Of
course, the horizon of inquisitiveness is indefinitely vast and this paper is just a single step
towards this direction.
In the present work, easily available low cost materials such as paper, graphite powder, silica
gel, aluminium paint are used in developing batteries. Various factors and characteristics
affecting the performance of paper battery were analyzed. It was found experimentally that the
OCV of paper battery increases appreciably with surface area and thickness of paper. The
specific combination of ordinary A4 size thick paper coated with graphite powder as cathode
and aluminium paint as anode, dipped in electrolyte yielded the maximum OCV of about 1 V.
This is appreciable, given the easily available low cost materials being used in the
development of the paper battery.
It can be concluded from the preliminary investigations that, there is a great potential in paper
battery that need be tapped further employing advanced technology. The theme may be
able to provide a promising energy solution for future power.

CHAPTER - 9
FUTURE SCOPE
Further extensive research is needed to conceive the idea of paper battery further. It is felt that
there is a need for improvement in areas such as the strength and basic structure, size reduction,
increasing OCV further and assessment of various evaluation parameters. Unfortunately, not
much work has been carried out India, except for a few notable ones.The work is carried
out as a joint research project of the Kalasalingam University in Krishnankovil, India;
the Indian Institute of Technology ,Mumbai; and IMRAM Tohoku University in
Japan, assisted by India’s Department of Science and Technology. Kalasalingam
University’s G. Hirankumar brought optimized cathode materials (CNT) to Tohoku
University’s laboratories for three months of joint development. Research is going on.
Widespread commercial deployment of paper batteries will rely on the development of more
inexpensive manufacturing techniques for carbon nanotubes. As a result of the potentially
transformative applications in electronics, aerospace, hybrid vehicles and medical science,
however, numerous companies and organizations are pursuing the development of paper
batteries. In addition to the developments announced in 2007 at RPI and MIT, researchers in
Singapore announced that they had developed a paper battery powered by ionic solutions in
2005. NEC has also invested in R & D into paper batteries for potential applications in its
electronic devices. Specialized paper batteries could act as power sources for any number of
devices implanted in humans and animals, including RFID tags, cosmetics, drug-delivery
systems and pacemakers. A capacitor introduced into an organism could be implanted fully dry
and then be gradudally exposed to bodily fluids over time to generate voltage. Paper batteries are
also biodegradable, a need only partially addressed by current e-cycling and other electronics
disposal methods increasingly advocated for by the green computing movement.

REFERENCES
1. Pandharipande S.L, Rewatkar Madhura R “PRELIMINARY INVESTIGATION IN
DEVELOPING PAPER BATTERIES FROM LOW COST MATERIALS” International Journal
of Advanced Engineering Research and Studies, April-June,2014.
2. A. Ganguly , S. Sar “PAPER BATTERY-A PROMISING ENERGY SOLUTION
FOR INDIA” International Journal of Advanced Engineering Research and Studies Vol. I/ Issue
I/October-December, 2011.
3. Nojan Aliahmad, Student Member, IEEE, Mangilal Agarwal, Member, IEEE, Sudhir Shrestha,
Member, IEEE, and Kody Varahramyan, Senior Member, IEEE “Paper-Based Lithium-Ion
Batteries Using Carbon Nanotube-Coated Wood Microfibers” IEEE TRANSACTIONS ON
NANOTECHNOLOGY, VOL. 12, NO. 3, MAY 2013.
4. Isabel Ferreira, Bruno Brás, Nuno Correia, Pedro Barquinha, Elvira Fortunato, and Rodrigo Martins
“Self-Rechargeable Paper Thin-Film Batteries: Performance and Applications” JOURNAL OF
DISPLAY TECHNOLOGY, VOL. 6, NO. 8, AUGUST 2010
5. Liangbing Hu, Hui Wu, Fabio La Mantia, Yuan Yang, and Yi Cui “Thin, Flexible Secondary
Li-Ion Paper Batteries” Department of Materials Science and Engineering, Stanford University,
Stanford, California, VOL 4.
6. www.intechopen.com
7. www.technicaljournalsonline.com
8. www.cnanotech.com
9. powerelectronics.com
10. www.greenoptimistic.com

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