07-05-2012, 03:45 PM
Lithium-Ion Battery + Nano-technology
[attachment=21485]
Battery Chemistry 101
Electrochemical reaction - a chemical reaction between elements which creates electrons.
Oxidation occurs on the metals (“electrodes”), which creates the electrons.
Electrons are transferred down the pile via the saltwater paper (the “electrolyte”).
A charge is introduced at one pole, which builds as it moves down the pile.
Primary vs. Secondary Batteries
Primary batteries are disposable because their electrochemical reaction cannot be reversed.
Secondary batteries are rechargeable, because their electrochemical reaction can be reversed by applying a certain voltage to the battery in the opposite direction of the discharge.
Recharge-ability & the “memory effect”
Recharge-ability: basically, when the direction of electron discharge (negative to positive) is reversed, restoring power.
the Memory Effect: (generally) When a battery is repeatedly recharged before it has discharged more than half of its power, it will “forget” its original power capacity.
Cadmium crystals are the culprit! (NiCd)
Lithium (Ion) Battery Development
In the 1970’s, Lithium metal was used but its instability rendered it unsafe and impractical. Lithium-cobalt oxide and graphite are now used as the lithium-Ion-moving electrodes.
The Lithium-Ion battery has a slightly lower energy density than Lithium metal, but is much safer. Introduced by Sony in 1991.
[attachment=21485]
Battery Chemistry 101
Electrochemical reaction - a chemical reaction between elements which creates electrons.
Oxidation occurs on the metals (“electrodes”), which creates the electrons.
Electrons are transferred down the pile via the saltwater paper (the “electrolyte”).
A charge is introduced at one pole, which builds as it moves down the pile.
Primary vs. Secondary Batteries
Primary batteries are disposable because their electrochemical reaction cannot be reversed.
Secondary batteries are rechargeable, because their electrochemical reaction can be reversed by applying a certain voltage to the battery in the opposite direction of the discharge.
Recharge-ability & the “memory effect”
Recharge-ability: basically, when the direction of electron discharge (negative to positive) is reversed, restoring power.
the Memory Effect: (generally) When a battery is repeatedly recharged before it has discharged more than half of its power, it will “forget” its original power capacity.
Cadmium crystals are the culprit! (NiCd)
Lithium (Ion) Battery Development
In the 1970’s, Lithium metal was used but its instability rendered it unsafe and impractical. Lithium-cobalt oxide and graphite are now used as the lithium-Ion-moving electrodes.
The Lithium-Ion battery has a slightly lower energy density than Lithium metal, but is much safer. Introduced by Sony in 1991.