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A Review of Rechargeable Battery Technologies
Naveen SINGAMSETTI, Sabri TOSUNOGLU
Department of Mechanical and Materials Engineering, Florida International University
Miami, Florida 33174, USA
ABSTRACT
Modern day dependence on the electricity has grown
enormously, especially the portable form of energy storage
systems; that is, batteries. The exponential growth in the
modern day-to-day usage of electronic devices, such as
cellphones, mp3 players, tablets, laptops, and so on, demands a
more efficient way of storing excess amount of energy. Hence,
rechargeable batteries represent a very important area of
technology where improvements would greatly help engineers
to create longer-lasting, lighter devices and reduce waste at the
same time. In order to develop new batteries, a basic
understanding of available battery technologies is important and
this paper focuses on reviewing most important rechargeable
battery types and assesses advantages and disadvantages.
Keywords: Rechargeable batteries, classification, primary
battery, secondary battery.
2. CLASSIFICATION OF CELLS & BATTERIES
Electrochemical cells and batteries are identifies as primary or
secondary (rechargeable), depending on their capability of
being electrically recharged. Within this classification, other
classifications are used to identify particular structures or
designs. The classification is as follow:
1. CELLS AND BATTERIES
A battery is a device that converts the chemical energy
contained in its active materials directly into electric energy by
means of an electrochemical oxidation-reduction (redox)
reaction. This type of reaction involves the transfer of electrons
from one material to another through an electric circuit.
Batteries currently contain one or more of the following eight
metals: cadmium, lead, zinc, manganese, nickel, silver, mercury
and lithium. While the term ‘‘battery’’ is often used, the basic
electrochemical unit being referred to is the ‘‘cell.’’ Cell: A cell
is the basic electrochemical unit providing a source of electrical
energy by direct conversion of chemical energy. Battery: A
battery consists of one or more electrochemical cells,
electrically connected in an appropriate series/parallel
arrangement to provide the required operating voltage and
current levels, including, if any, monitors, controls and other
ancillary components, case, terminals and markings [2].
The primary battery is a convenient, usually inexpensive,
lightweight source of packaged power for portable electronic
and electric devices, lighting, photographic equipment, toys,
memory backup, and a host of other applications, giving
freedom from utility power. The general advantages of primary
batteries are good shelf life, high energy density at low to
moderate discharge rates, little, if any, maintenance, and ease of
use. Although large high- capacity primary batteries are used in
military applications, signaling, standby power, and so on, the
vast majority of primary batteries are the familiar single cell
cylindrical and flat button batteries or multicell batteries using
these component cells.
Major Components of Cells:
1. The anode or negative electrode: the reducing or fuel
electrode—which gives up electrons to the external
circuit and is oxidized during the electrochemical
reaction.
2. The cathode or positive electrode: the oxidizing
electrode—which accepts electrons from the external
circuit and is reduced during the electrochemical
reaction.
3. The electrolyte: the ionic conductor—which provides
the medium for transfer of charge, as ions, inside the
cell between the anode and cathode. The electrolyte is
typically a liquid, such as water or other solvents,
with dissolved salts, acids, or alkalis to impart ionic
conductivity. Some batteries use solid electrolytes,
which are ionic conductors at the operating
temperature of the cell.
Primary Cells or Batteries
The term “primary” was first used to describe this type based on
the fact that the materials inside the battery were the prime
source of the electric power it delivered. These batteries are not
capable of being easily or effectively recharged electrically and,
hence, are discharged once and discarded. Many primary cells
in which the electrolyte is contained by an absorbent or
separator material (there is no free or liquid electrolyte) are
termed ‘‘dry cells.’’
Secondary or Rechargeable Cells or Batteries
Passing current through them in the opposite direction to that of
the discharge current can recharge these batteries electrically.
They are storage devices for electric energy and are known also
as ‘‘storage batteries’’ or ‘‘accumulators.’’ The applications
of secondary batteries fall into two main categories: (i) Those
applications in which the secondary battery is used as an
energy-storage device, generally being electrically connected to
and charged by a prime energy source and delivering its energy
to the load on demand. Examples are automotive and aircraft
systems, emergency no-fail and standby (UPS) power sources,
hybrid electric vehicles and stationary energy storage (SES)
systems for electric utility load leveling. (ii). Those applications
in which the secondary battery is used or discharged essentially
as a primary battery, but recharged after use rather than being
discarded. Secondary batteries are used in this manner as, for
example, in portable consumer electronics, power tools, electric
vehicles, etc., for cost savings (as they can be recharged rather
than replaced), and in applications requiring power drains
beyond the capability of primary batteries.
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
Systemics, Cybernetics and Informatics, WMSCI 2012, Orlando, Florida, July 17-20, 2012.
3. COMPONENTS OF A CELL
A cell is a basic building block of all batteries. It consists of two
electrodes (an anode and a cathode), electrolyte, a separator
between the anode and cathode, and some type of cell container.
Anode
Anode is the negative electrode. It is the reducing electrode,
also known as the fuel electrode. The anode gives up its
electrons to the external circuit and is oxidized in the process.
Anodes are made from materials with very few electrons in
their valence shell. Almost all anodes are made from either
metals or compounds that include metals.
Cathode
The positive electrode, also known as the oxidizing electrode.
This is designed to accept electrons from the external circuit
and is reduced in the process. Cathodes are made from materials
that have nearly full valence shells. Cathodes are typically made
from compounds that include oxygen, chlorine, or both.
Electrolyte
The ionic conductor. While the electrons pass through the
external circuit, the electrode materials inside the cell change
into ions. In order to sustain the flow of electrons, the newly
formed ions have to pass between the electrodes through the
electrolyte. Electrolytes are typically either acids or bases
(alkaline), although newer technologies tend to use organic
solvent and salt solutions. Acids, bases, and salt solutions all
make good ionic conductors.
Separator
The separator provides insulation between the anode and
cathode while allowing ionic transport between the electrodes.
4. ELECTROCHEMICAL ACTION
When the anode is connected to the cathode through an external
circuit, the cell undergoes discharge. REDOX occurs: the anode
material loses electrons (oxidation) and the cathode material
gains electrons (reduction). For rechargeable batteries, applying
a voltage in the reverse direction (from discharge) institutes
REDOX in the opposite direction. In a battery, REDOX occurs
only at the surface of the electrodes. A reaction involving the
entire mass of both a reducing agent and an oxidizer would be
either a fire or an explosion.
Discharge
The flow of electrons from the anode to the cathode through an
electric circuit. Ions form on both electrodes and flow through
the electrolyte to react with one another to form new stable
compounds. In most practical batteries, the discharge product is
formed on the surface of the cathode.
Charge
The flow of electrons from the cathode to the anode induced by
an external power source. The discharge product separates out
into ions that travel through the electrolyte. The original
electrode materials return to their starting points
Cell Voltage
Cell voltage is dependent in part on the electrode potential of
the materials chosen, typically referred to as the “standard
reduction potential”. A table of common electrode potentials is
given in table 1 and the theoretical voltage of a given cell is the
difference in potential between the two materials. This can be
determined using a number line in figure 1.
Figure 1 Number line showing theoretical cell voltage
Table 1 Electrode potential for some common battery
chemistries
ANODE MATERIALS
CATHODE MATERIALS
Material
Potential
Material
Potential
Zinc
Zinc
Lithium
Lead
Cadmium Hydroxide
-0.76 (in acid electrolyte)
-1.25 (in base electrolyte)
-3.01
-0.13
-0.81
Chlorine
Oxygen
Sulfur Dioxide
Lead Dioxide
Nickel (as NiOOH)
1.36
1.23
0.0
1.69
0.49
El e c t r o n f l o w
(-)
El e c t r o n f l o w
(+ )
D IS C H A R G E
(-)
(+ )
CHARGE
Figure 2 Discharge and charge process in a basic cell
The potential is an “absolute” value, determined by the total
value between the two points. The lithium sulfur dioxide
potential is obvious, since sulfur dioxide has a zero-volt
potential. The absolute value of the difference between them is
3.01 volts. The nickel-cadmium potential isn’t so obvious. The
absolute difference between –0.81 volts and +0.49 volts is 1.30
volts, the total difference between them, or rather, the total
distance between the two points on the number line.
5. IMPORTANT RECHARGEABLE BATTERY TYPES
i. Lead acid batteries
Brief History
Lead–acid batteries, invented in 1859 by French physicist
Gaston Planté, are the oldest type of rechargeable battery.
Despite having a very low energy-to-weight ratio and a low
energy-to-volume ratio, their ability to supply high surge
currents means that the cells maintain a relatively large powerto-weight ratio. These features, along with their low cost, make
them attractive for use in motor vehicles to provide the high
current required by automobile starter motors.
Table 2 Lead acid battery characteristics
Specific energy
Energy density
Specific power
Charge discharge efficiency
Self discharge rate
Cycle durability
Nominal cell voltage
30-40 Wh/kg
60-75 Wh/l
180 W/kg
50%-92%
3-20% / month
500-800 cycles
2.105 volts
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
Systemics, Cybernetics and Informatics, WMSCI 2012, Orlando, Florida, July 17-20, 2012.
5.
6.
performance
Good float service
Low cost compared with other secondary batteries
Disadvantages
1. Relatively low cycle life (50–500 cycles)
2. Limited energy density—typically 30–40 Wh/kg
3. Difficult to manufacture in very small sizes
4. Hydrogen evolution in some designs can be an
explosion hazard
5. Stibene and arsine evolution in designs with antimony
and arsenic in grid alloys can be a health hazard
Figure 2 Schematic of Lead acid battery
Electrochemistry
In the charged state, each cell contains negative electrodes of
elemental lead (Pb) and positive electrodes of lead(IV) oxide
(PbO2) in an electrolyte of approximately 33.5% v/v (4.2 Molar)
sulfuric acid (H2SO4). In the discharged state both the positive
and negative become lead (II) sulfate (PbSO4) and the
electrolyte loses much of its dissolved sulfuric acid and
becomes primarily water. Due to the freezing-point depression
of water, as the battery discharges and the concentration of
sulfuric acid decreases, the electrolyte is more likely to freeze
during winter weather. During discharge, both plates return to
lead sulfate. The process is driven by the conduction of
electrons from the positive plate back into the cell at the
negative plate.
Applications
Automotive, marine, aircraft, diesel engines in vehicles and for
stationary power, Industrial trucks, Electric vehicles, golf carts,
hybrid vehicles, mine cars, personnel carriers
ii. Alkaline battery
Brief History
The first generation rechargeable alkaline technology was
developed by Battery Technologies Inc. in Canada and licensed
to Pure Energy, EnviroCell, Rayovac, and Grandcell.
Subsequent patent and advancements in technology have been
introduced. The shapes include AAA, AA, C, D, and Snap-on
9-volt batteries. Rechargeable alkaline batteries have the ability
to carry their charge for years, unlike most NiCd and NiMH
batteries which self-discharge in 90 days (see below **).
However, new low self-discharge NiMH cells, such as Sanyo
"Eneloop", claim to retain 90% charge after 1 year. If produced
properly, rechargeable alkaline batteries can have a
charge/recharge efficiency of as much as 99.9% and be an
environmentally friendly form of energy storage.
Negative Plate Reaction: Pb(s) + HSO−4(aq) → PbSO4(s) +
2e−
Positive Plate Reaction: PbO2(s) + HSO-4(aq) + 3H+(aq) + 2e−
→ PbSO4(s) + 2H2O(l)
Subsequent charging places the battery back in its charged state,
changing the lead sulfates into lead and lead oxides. The
process is driven by the forcible removal of electrons from the
negative plate and the forcible introduction of them to the
positive plate.
Negative Plate Reaction: PbSO4(s) + H+(aq) + 2e− → Pb(s) +
HSO−4(aq)
Figure 3 Schematic of alkaline manganese dioxide battery
Positive Plate Reaction: PbSO4(s) + 2H2O(l) → PbO2(s) +
HSO−4(aq) + 3H+(aq) + 2e−
Table 3 Alkaline battery characteristics
Overcharging with high charging voltages generates oxygen and
hydrogen gas by electrolysis of water, which is lost to the cell.
Periodic maintenance of lead acid batteries requires inspection
of the electrolyte level and replacement of any water that has
been lost.
Advantages
1. Popular low-cost secondary battery—capable of
manufacture on a local basis, worldwide, from low to
high rates of production
2. Available in large quantities and in a variety of sizes
and designs—manufactured in sizes from smaller than
1 Ah to several thousand Ampere-hours
3. Good high-rate performance—suitable for engine
starting
4. Moderately good low- and high-temperature
Specific energy
Energy density
Specific power
Charge discharge efficiency
Self discharge rate
Cycle durability
Nominal cell voltage
85 Wh/kg
250 Wh/l
50 W/kg
85%
12% / month
100-1000 cycles
1.5 volts
Electrochemistry
In an alkaline battery, the anode (negative terminal) is made of
zinc powder, which gives more surface area for increased
current, and the cathode (positive terminal) is composed of
manganese dioxide. Unlike zinc-carbon (Leclanché) batteries,
the electrolyte is potassium hydroxide rather than ammonium
chloride or zinc chloride.
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
Systemics, Cybernetics and Informatics, WMSCI 2012, Orlando, Florida, July 17-20, 2012.
The half-reactions are
Zn(s) + 2OH−(aq) → ZnO(s) + H2O(l) + 2e−
2MnO2(s) + H2O (l) + 2e− →Mn2O3(s) + 2OH−(a
A single charge/discharge process makes a cycle.
Advantages
1. Low initial cost (and possible lower operating cost
than other rechargeable batteries)
2. Manufactured in a fully charged state
3. Good retention of capacity
4. Completely sealed and maintenance-free
5. No ‘‘memory effect’’ problem
Disadvantages
1. Useful capacity about two-thirds of primary battery
but higher than most rechargeable batteries
2. Limited cycle life
3. Available energy decreases rapidly with cycling and
depth of discharge
4. Higher internal resistance than NiCd and NiMH
iii. Nickel iron battery
Brief History
The nickel–iron battery (NiFe battery) is a storage battery
having a nickel (III) oxide-hydroxide cathode and an iron
anode, with an electrolyte of potassium hydroxide. The active
materials are held in nickel-plated steel tubes or perforated
pockets. It is a very robust battery, which is tolerant of abuse,
(overcharge, over discharge, and short-circuiting) and can have
very long life even if so treated. It is often used in backup
situations where it can be continuously charged and can last for
more than 20 years. Due to its low specific energy, poor charge
retention, and its high cost of manufacture, other types of
rechargeable batteries have displaced the nickel–iron battery in
most applications.
They are currently gaining popularity for off-the-grid
applications where daily charging makes them an appropriate
technology
Electrochemistry
The cell electrodes are able to store energy obtained from an
exterior charging source to return this energy. To do this they
need to be immersed in an electrolyte.
Initial active material of the positive electrodes is nickel
dihydroxide and active material of the negative electrode is
ferrous dihydroxide.
The basic processes taking place in accumulators during
charging and discharging can be represented with the following
equation.
Charge:
2Ni(OH)2 + Fe(OH)2 2NiOOH + 2H2O
Discharge:
2NiOOH + 2H2O 2Ni(OH)2 + Fe(OH)2
During charging, the basic current generating process of ferrous
reduction will consume water and release oxygen from negative
(iron) plate, and oxidation of nickel dihydroxide will release
hydrogen from the positive (nickel) plate. During discharge,
ferrous oxidation will consume water and release hydrogen
from the negative plate and reduction at the positive plate will
consume water and release oxygen. Also during charging a
certain amount of electrolysis of water from the electrolyte
takes place, with the formation of hydrogen at the negative
electrode and oxygen on the positive electrode.
Figure 4 Changes that occur during charge and discharge of
a nickel iron cell
Table 4 Nickel iron battery characteristics
Specific energy
Energy density
Specific power
Charge discharge efficiency
Self discharge rate
Cycle durability
Nominal cell voltage
85 Wh/kg
250 Wh/l
50 W/kg
85%
12% / month
100-1000 cycles
1.5 volts
Advantages
1. Physically almost indestructible
2. Long life
3. Withstands electrical abuse:
discharged, short-circuiting
overcharge,
over
Disadvantages
1. High self-discharge
2. Hydrogen evolution on charge and discharge
3. Low power density
4. Damaged by high temperatures
Applications
1. Railways
2. Mining industry
3. Industrial enterprises
4. Various equipment
5. Electric cars and bikes
6. Solar, renewable power storage
iv. Nickel cadmium battery
Brief History
The nickel–cadmium battery (Ni–Cd battery) (commonly
abbreviated NiCd or NiCad) is a type of rechargeable battery
using nickel oxide hydroxide and metallic cadmium as
electrodes.
The abbreviation NiCad is a registered trademark of SAFT
Corporation, although this brand name is commonly used to
describe all Ni–Cd batteries. The abbreviation NiCd is derived
from the chemical symbols of nickel (Ni) and cadmium (Cd).
Electrochemistry
Ni–Cd batteries usually have a metal case with a sealing plate
equipped with a self-sealing safety valve. The positive and
negative electrode plates, isolated from each other by the
separator, are rolled in a spiral shape inside the case. This is
known as the jellyroll design and allows a Ni–Cd cell to deliver
a much higher maximum current than an equivalent size
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
Systemics, Cybernetics and Informatics, WMSCI 2012, Orlando, Florida, July 17-20, 2012.
alkaline cell. Alkaline cells have a bobbin construction where
the cell casing is filled with electrolyte and contains a graphite
rod, which acts as the positive electrode. As a relatively small
area of the electrode is in contact with the electrolyte (as
opposed to the jelly-roll design), the internal resistance for an
equivalent sized alkaline cell is higher which limits the
maximum current that can be delivered.
The chemical reactions during discharge are:
Cd + 2OH- Cd(OH)2 + 2eat the cadmium electrode, and
2NiO(OH) + 2H2O + 2e- 2Ni(OH)2 + 2OHat the nickel electrode. The net reaction during discharge is
2NiO(OH) + Cd + 2H2O 2Ni(OH)2 + Cd(OH)2
During recharge, the reactions go from right to left. The alkaline
electrolyte (commonly KOH) is not consumed in this reaction
and therefore its Specific Gravity, unlike in lead–acid batteries,
is not a guide to its state of charge.
small electronics
Used in cord less phones, wireless telephones,
emergency lighting
v. Lithium ion batteries
Brief History
A lithium-ion battery (sometimes Li-ion battery or LIB) is a
family of rechargeable battery types in which lithium ions move
from the negative electrode to the positive electrode during
discharge, and back when charging. Chemistry, performance,
cost, and safety characteristics vary across LIB types. Unlike
lithium primary batteries (which are disposable), lithium-ion
electrochemical cells use an intercalated lithium compound as
the electrode material instead of metallic lithium.
3.
Lithium-ion batteries are common in consumer electronics.
They are one of the most popular types of rechargeable battery
for portable electronics, with one of the best energy densities,
no memory effect, and a slow loss of charge when not in use.
Beyond consumer electronics, LIBs are also growing in
popularity for military, electric vehicle, and aerospace
applications. Research is yielding a stream of improvements to
traditional LIB technology, focusing on energy density,
durability, cost, and intrinsic safety.
Figure 6 Schematic diagram of a wound prismatic cell
Figure 5 Schematic of Nickel cadmium battery
Advantages
1. Rugged; can withstand electrical and physical abuse
2. Long cycle life
3. Reliable; no sudden death
4. Good charge retention
5. Excellent long-term storage
6. Low maintenance
Disadvantages
1. Low energy density
2. Higher cost than lead-acid batteries
3. Contains cadmium
Applications
1. Used in portable electronics and toys.
2. Comes in the forms of button cells and can be used in
Specific energy
Energy density
Specific power
Charge discharge efficiency
Self discharge rate
Cycle durability
Nominal cell voltage
40-60 Wh/kg
50-150 Wh/l
150 W/kg
70-90%
10% / month
2000 cycles
1.2 volts
Table 5 Lithium ion battery characteristics
Specific energy
Energy density
Specific power
Charge discharge efficiency
Self discharge rate
Cycle durability
Nominal cell voltage
100-250 Wh/kg
250-620 Wh/l
~250-~350W/kg
80-90%
8% / month
400-1200 cycles
3.6/3.7 volts
Electrochemistry
The three participants in the electrochemical reactions in a
lithium-ion battery are the anode, cathode, and electrolyte.
Both the anode and cathode are materials into which, and from
which, lithium can migrate. During insertion (or intercalation)
lithium moves into the electrode. During the reverse process,
extraction (or deintercalation), lithium moves back out. When a
lithium-based cell is discharging, the lithium is extracted from
the anode and inserted into the cathode. When the cell is
charging, the reverse occurs.
Useful work can only be extracted if electrons flow through a
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
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closed external circuit. The following equations are in units of
moles, making it possible to use the coefficient x.
The positive electrode half-reaction (with charging being
forwards) is
[5] Little, A. D. (1993). Survey of rechargeable battery
technologies. Cambridge.
[6] Reddy, J. O. (1970). Modern Electrochemistry. Plenum.
[7] Sequeira, C. Solid State Batteries. North Atlantic Treaty
Organization.
LiCoO2Li1-xCoO2 + xLi+ + xeThe negative electrode half-reaction is:
xLi+ + xe- + 6C  LixC6
The overall reaction has its limits. Over discharge
supersaturates lithium cobalt oxide, leading to the production of
lithium oxide, possibly by the following irreversible reaction:
Li+ + e- + LiCoO2 Li2O + CoO
Advantages
1. Sealed cells; no maintenance required
2. Broad temperature range of operation
3. Rapid charge capability
4. High rate and high power discharge capability
5. High coulombic and energy efficiency
6. No memory effect
Disadvantages
1. Moderate initial cost
2. Degrades at high temperature
3. Need for protective circuitry
4. Capacity loss or thermal runaway when over-charged.
5. Venting and possible thermal runaway when crushed
Applications
Portable electronics, medicine, military equipment, LithiumIon-Polymer Battery
Chemical Hazards of Using Rechargeable Batteries
Batteries are usually filled with solutions (electrolytes)
containing either sulphuric acid or potassium hydroxide. These
very corrosive chemicals can permanently damage the eyes and
produce serious chemical burns to the skin. Sulphuric acid and
potassium hydroxide are also poisonous if swallowed.
The lead, nickel, lithium or cadmium compounds often found in
batteries are harmful to humans and animals. These chemicals
can also seriously damage the environment.
6. CONCLUSION
This paper reviewed previously-developed batteries and
provided a classification of technologies indicating advantages
and disadvantages of each. Emphasis is made on rechargeable
batteries since they require urgent improvements required by
the ever increasing demand on electronic devices – cell phones,
tablets and so on. The summary of past developments is
intended to provide a roadmap for future developments.
7. REFERENCES
[1] Broad, R. J. Recent Developments in Batteries for
Portable Consumer Electronics Applications. pennington,
NJ, 1999: electrochemical society.
[2] Connolly, D. (2009). A Review of Energy Strorage
Technologies. University of Limerick.
[3] Espinar, B. (2011). The role of energy storage for minigrid stabilization. Armines: Mines Paris Tech.
[4] Linden, D. (2002). Handbook of batteries. new york:
McGraw Hill.
The 8th International Symposium on Management, Engineering and Informatics, MEI 2012, and The 16th World Multi-Conference on
Systemics, Cybernetics and Informatics, WMSCI 2012, Orlando, Florida, July 17-20, 2012.