1. Battery: The battery is a device consisting of one or more
electrochemical cells connected with one another in a series
that converts stored chemical energy into electrical energy.
BATTERY CHEMISTRY
Introduction:
2. Clssification:
Primary Battery (or) Primary cell)
The battery in which the cell reaction is not reversible is called ‘ a primary cell’. In primary cell
when most of the reactants have converted to products, the cell no longer produce current
and the cell is said to be ‘dead’.
Eg: Dry Cell (Leclanche cell), Lithium Cell etc.
3. Secondary Battery (or) Secondary cell
The battery in which the cell reactions are reversible is called ‘a secondary cell’. These cells
can be used by carrying a large no of cycles of charging & discharging.
Eg: Lead-Acid battery, Lithium ion cell, Ni-Cd battery etc
4. Flow Battery ( or Fuel cell ):it is Also known as “continuous
battery”,
It is an electro chemical cell that converts chemical energy
into electrical energy, in which materials (reactants, products,
electrolytes) pass through the battery.
• Eg: Methanol-Oxygen fuel cell, hydrogen-oxygen fuel cell etc.
5. 4) Reserve battery: Also known as “activated battery”,
it is a kind of battery in which the positive and negative active
substances are not in direct contact with the electrolyte, and the
electrolyte is temporarily injected or activated by other methods
before use. The positive and negative active substances of
such batteries are chemically deteriorated or self discharged,
which are basically eliminated due to isolation from the
electrolyte, so that the batteries can be stored for a long time.
Eg: magnesium silver batteries, calcium thermal batteries and
lead perchloric acid batteries.
6. Basic requirements of commercial batteries
Strong Starting Power: The industrial sector requires robust usage of the
batteries. Thus, the supply needs to offer a strong starting power.
Long-Running Time: Heavy-duty batteries need a longer running time to
maximize operational efficiencies.
Adaptable: The heavy-duty battery should be able to handle and endure
changing and various climatic conditions.
Durable: The batteries need to withstand constant jarring and high usage
Long Product Life: A long product life is essential to effectively manage
operational costs.
7. Zn-Air battery (Metal-Air Battery)
Zn-Air battery is a modern and metal –air battery.It uses oxygen from the
atmosphere and dose not contribute to the weight of the battery so these
batteries offer higher energy density
Construction:
Anode : A Loose granulated Zn powder
Cathode : C -porous carbon plate(blended with catalyst- MnO + Teflone )/
Air (Active material at cathode is 𝑶𝟐 from air)
Electrolyte :KOH 6M
Separator : polyethylene(Electrolyte absorbent separator )
*High energy densities achieved
Cell gives a voltage of 1.4v, Energy density 100Wh/Kg
Cell Representation : Zn ׀ KOH ׀ C, air
10. Applications;
1) Used in military radio receivers
2) Used as a power sources in hearing aid
3) Used in electronic pagers & various medical devices
Advantages:
High energy density
Low cost
Dis advantages :
Limited power output
Limited Shelf life
11. • A LIB is a type of rechargeable battery in which intercalated Li compounds are
used as the electrode materials.
Construction :
• Anode: LiCoO2 (which offers high energy density)
• Cathode: C (graphite) (highly crystallized specialty carbon )
Electrolyte: ( LiPF6),Lithium manganese oxide (LMO),(Lithium iron phosphate (LIP)
LITHIUM – ION BATTERY (LIB):
12. The chemical reactions for charging & discharging are shown below :
Positive electrode : LiCoO2
Charge
Discharge
Li 1-x CoO2 + xLi+ + xe-
Negative electrode: 6C + xLi+ + xe- Charge
Discharge
Lix C6
Net Reaction : LiCoO2 + 6C
Charge
Discharge
Li 1-x CoO2 + Lix C6
In LIB, the Li ions move from the negative electrode (anode) to positive electrode (cathode)
during discharge by reducing the cobalt from Co4+ to Co3+ and from positive electrode (anode) to
negative electrode (cathode) by oxidizing the cobalt from Co3+ to Co4+ during charging.
Working :
(Cathode)
(Anode)
13. • Advantages:
Li – ion battery is lighter compared to all other equivalent energy density
rechargeable batteries.
It has no memory effect. (i.e, discharge capacity of a battery is reduced when it
is repetitively discharged incompletely & then recharged )
Self discharge is very less & environmentally friendly [(5-10%)/month]
The nominal cell voltage is higher than other batteries (3.6 V).
• Disadvantages:
Deep discharge reduces the life cycle & maintained with 40% charge in
cold place.
It should be maintained with in safe voltage and current limits.
It should be often fully charged to prevent crystalline aging.
Restriction for transport due safety issue.
14. APPLICATIONS OF Li-ion Battery
The Li-ion batteries are used in cameras,calculators,smart phones and most of
the consumer electronic device
They are used in cardiac pacemakers and other implantable device
Electricle vehcles: Because of their light weight Li-ion batteries are used for
propelling a wide range of electric vehicles such as aircraft , electric
cars,pedelecs,hybride vehicles, advanced electric wheelchairs,radio controlled
models, aircraft and the mars curiosity rover.
Power tools :Li-ion batteries are used in tools such as cardlessdrills, sanders,
saws, and variety of garden equipment whipper- snippers and hedge trimmer
15. APPLICATIONS OF Li-ion Battery to electric vehicle
High energy per unit mass relative to other electrical energy storage
systems.
They also have a high power to ratio.
High energy efficiency
Good high temperature performance
Low self discharge
Most components of Li-ion batteries can recycled
