If you are able to read this post on the go,on the portable devices like mobile phones or Ipads, you must say thanks to the "Lithium Ion Battery"(Li-ion ) and their developers,who worked over the years to made this happen.
Wondering,why you must say thanks to them ? Read the full article to discover the answer.
• What is Battery ? And its classification.
• Why lithium is used in batteries?
• Working of Lithium Ion Battery.
• Battery Cycle
• Why lithium is used in batteries?
• Working of Lithium Ion Battery.
• Battery Cycle
What is Battery ?
Battery is an device which converts chemical energy directly into electric energy, which can provide power to electric portable devices like mobile phones, flashlights and even for Electric vehicles too.Fossil fuels like coal,oil,gas are currently primary energy sources and they fueled industrial revolution and global economic growth. However,due to its finite storage, harmful effects on climate,and increased global warming made world to search for the alternative or clean fuels.
Batteries can be classified into two types based on its "re-usability".
1. Primary Battery ( Non- Rechargeable /Single use)
2. Secondary Battery (Rechargeable )
Primary batteries are designed for the use until its energy exhausted and then it is disposed.There chemical reactions can not be reversible,so they are not rechargeable. On other hand, secondary batteries chemical reactions can be reversed,which makes them rechargeable.But, because of the internal corrosion and loss of electrolyte secondary batteries can be recharged at definite battery cycles only.
Why Lithium is used in batteries ?
Following are the main reasons of using Lithium in batteries.
• Highly reactive
Lithium is highly reactive because it readily loses its outermost electron, making it easy to get current flowing through a battery.
• Lighter in weight
Lithium is lighter in weight than Lead,which is needed for portable devices.
• Higher Energy Density
Lithium has energy density higher almost twice than nickel cadmium. Energy density is the amount of energy in given mass.
• Low self discharge
Compared to nickel cadmium,lithium has self discharge less than half.
How Li-ion battery works ?
Li-ion batteries consist of Anode, Cathode ,Separator, Electrolyte & two current collectors( Positive & Negative). Both the Anode & Cathode has the capability to store the Lithium ions.
Li-ion batteries consist of Anode, Cathode ,Separator, Electrolyte & two current collectors( Positive & Negative). Both the Anode & Cathode has the capability to store the Lithium ions.
Electrolyte is used to carry Lithium ions from anode to cathode & vice versa through separator.Below image shows the working of Li-ion battery.
Flow of Lithium Ions -
Flow of Lithium Ions -
State From To
While Charging - Cathode => Anode
While Discharging - Anode => Cathode
Image Source - http://large.stanford.edu/courses/2010/ph240/nie1/
Battery Cycle
According to the Apple, Apple Li-ions batteries work in battery cycles. One charge cycle is completed when you have discharged 100 % of your battery capacity but not necessarily all from one charge. For example, suppose you have used 75% of your battery capacity one day & charged again to 100% battery capacity.On next day, you have used 25% means you have discharged total 100 % of battery capacity in 2 days & this is considered as one complete battery cycle.
One Cycle
Charges
+100%
Discharges
-75%
+75%
-25%
+25%
One charge cycle is completed after you’ve discharged 100% of your battery’s capacity.
Common Facts about Li-ion Batteries -
1. First commercial Lithium Ion battery was made by Sony corporation in 1991.
2. For safety reasons,while travelling by flights,spare or uninstalled lithium metal or lithium-ion batteries are must be removed from check in baggage and should kept with passenger in carry on baggage.
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