Batteries

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Batteries
Batteries
Batteries store chemical energy and Chemical Energy in to
Electrical Energy.
Anatomy of a Battery
• The internal workings of a battery are typically housed within a
metal or plastic case. Inside this case are a cathode, which
connects to the positive terminal, and an anode, which connects
to the negative terminal. These components, more generally
known as electrodes.
• A separator creates a barrier between the cathode and anode,
preventing the electrodes from touching while allowing
electrical charge to flow freely between them….
• Batteries are used in many applications, Automobile Industry,
Power sector & in other Industrial Applications.
• In Automobiles energy from the battery is used to power
accessories, lighting and other electrical systems when the
engine is not running. To supply the ignition, fuel and starting
systems with the necessary power to start the vehicle
Anatomy of a Battery
• The medium that allows the electric charge to flow
between the cathode and anode is known as the
electrolyte
How do batteries work?
• Batteries create an uneven level of electrons which
causes the electrons to move from a high
concentration to a low concentration…
• This is also known as the voltage difference.
• The reaction in the anode creates electrons, and
the reaction in the cathode absorbs them. The net
product is electricity.
What are the different types of
batteries?
Two Major Type of Batteries.
Wet-Cell & Dry-Cell Batteries.
Modern batteries use a variety of chemicals to power
their reactions. Some of the more common types of
batteries are:
• Zinc-carbon battery or standard carbon battery
• Alkaline battery
• Lithium battery
• Lithium-ion battery
• Lead-acid battery
• Nickel-cadmium or NiCad battery
Wet cell – Dry cell Batteries
• Wet cell batteries contain a liquid electrolyte solution which
consists of sulphuric acid and water. Also known as
Vented/flooded acid batteries
• Wet cells will produce 2.1 Volts each and 6 cells connected
in series (+ - ) allows them to produce the 12.6 - (12) Volts
used by the automobile.
• The main concern for wet cell batteries in all applications is
leaking sulfuric acid, as it is a dangerous corrosive that can
damage what it contacts and can burn human tissue.
• Dry cell batteries will only produce 1.5 Volts per cell and can
be connected in series (to produce more voltage). Dry cell
batteries are batteries, which the electrolytes are in form of
moist paste. They also refer to electrical batteries, which the
electrochemical cells converts stored chemical energy into
electrical energy.
Wet cell Batteries
5. Lead-acid battery:
• This is the chemistry used in a typical car battery.
The electrodes are usually made of lead dioxide
and metallic lead, while the electrolyte is a sulfuric
acid solution. The amount and size of plates in a
battery cell, determine the capacity of the battery.
• Example,
• Automobiles Batteries.
Dry cell Batteries
1. Zinc-carbon battery:
• Zinc and carbon are used in all regular or standard AA,
C and D dry-cell batteries. The electrodes are made of
zinc and carbon, with a paste of acidic materials
(ammonium chloride or zinc chloride) between them
serving as the electrolyte.
2. Alkaline battery:
• This chemistry is common in AA, C and D dry cell
batteries. The cathode is composed of a manganese
dioxide mixture, while the anode is a zinc powder. It
gets its name from the potassium hydroxide electrolyte,
which is an alkaline substance……
Dry cell Batteries
3. Lithium battery:
• These batteries are used in cameras for the flash bulb. They
are made with lithium, lithium-iodide and lead-iodide. They
can supply surges of electricity for the flash.
4. Lithium-ion battery:
• Lithium chemistry is often used in high-performance
devices, such as cell phones, digital cameras and even
electric cars. A variety of substances are used in lithium
batteries, but a common combination is a lithium cobalt
oxide cathode and a carbon anode.
5. Nickel-Cadmium(nicad) Batteries:
• The nicad system requires 10 series cells to reach a potential
of 12 VDC.
Dry Cell Battery
Selection and Sizing of Battery
• The duty cycle imposed on the battery will depend on the DC
system design and the load requirements. The duty cycle
showing the battery loads in amperes and the lengths of time for
which they must be supported will determine the sizing of the
battery. Loads may be classified as continuous or noncontinuous.
Selection and Sizing of Battery
Continuous loads:
Continuous loads are classified as steady-state loads.
Continuous loads are energized throughout the duty
cycle and are normally supplied by the battery
charger. Examples of typical continuous loads are
• Lighting
• Indicating lights
• Continuously energized coils and operating motors
Selection and Sizing of Battery
Non-continuous loads
Non-continuous loads lasting 1 min or less are known
as momentary loads or short-time loads. Examples of
typical non-continuous loads are
• Circuit breaker operations
• Motor operated valves
• Inrush currents of motors or other devices
• Field flashing of generators or synchronous motors
Maintenance and Care of Batteries
for Long Life
The monitoring and maintenance of batteries is very important
from the point of view of service reliability.
• Inspections:
Periodic inspection can provide information on the battery
conditions and its state of health. All inspections should be made
under normal float conditions. Inspection should be made at least
once a month and should include the following checks:
• Float voltage at battery terminals
• Charger output current and voltage
• General appearance and cleanliness of the battery
• Electrolyte levels, cracks in jars, and leakage of electrolyte
• Evidence of corrosion at terminals, connectors, racks, or cabinets
Wet & Dry Cell Merits & Demerits
• Merits:
• Merits:
1. Most economical among diff types
of batteries.
• These Cells have voltage ranging
from 1.25V-1.50V
2. Robust- not much sensitive to
temperature.
• Small sized, Primary Cells are used
in torches, radios, hearing aid
devices, watches etc.
• Demerits
1. Needs periodic maintenancetwice a month.
2. Emits corrosive fumes.
3. Needs special battery room with
acid proof tilling.
4. Cannot be transported in charged
condition, initial charging takes 55
to 90 hours.
5. Needs specially trained persons for
handling due highly hazardous
sulphuric acid.
• Demerits
• These cells does not have long life,
because the Acidic NH4Cl corrodes
the container even when the cells
are not in use.
WHAT NOT TO DO WITH
BATTERIES
The following is detrimental to the life span of a battery:
• Incorrect charge voltage.
• Too low a voltage means that the battery does not charge to 100% - the sulphate then hardens
on the plates and the battery loses some of it capacity. Excessive voltage causes the batteries
to generate excessive gas leading to water los and drying out.
• Excessive discharging.
• Discharging a battery further than its capacity greatly shortens its life span
• Too many cycles, high charge voltage, excessive discharging and significant voltage ripple in the
charge voltage caused by cheap chargers and alternators.
• Charging without 3 step regulation and very high electrolyte temperatures.
BATTERY
TERMINOLOGY
• VRLAB
Flooded Valve Regulated Lead Acid Batteries
• GEL
Gelled Electrolyte Lead Acid Battery
• AGM
Advanced Glass Mat Battery
• CCA
Cold Cranking Amps -18°C terminal V ≥7.2V for 30 sec.
• CA
Cranking Amps
0°C terminal V ≥7.2V for 30 sec.
• RC
Reserve Capacity 25°C terminal V ≥ 10.5V 25A Load = time
• AH
100Ah = 20 hrs @ 5A load terminal V ≥ 10.5V
• Peukert Exponent (ⁿ) Charge factor indicating efficiency of a battery
Flooded cell battery is 80%. Must be recharged 1.2 times the capacity to reach
100%. Dynamic. Lower the factor – more efficient. Lithium-Ion 1.05.
• Cp=Iⁿt
Battery capacity = Discharge Current ⁿ x Time hrs
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