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Alessandro Volta. Born in Como, Italy on February 18, 1745 Volta was educated in the public schools of Como In 1774, he became a professor at the Royal School of Como. While teaching, Volta made his first invention, the electrophorus: a device that produced static electricity.
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Alessandro Volta • Born in Como, Italy on February 18, 1745 • Volta was educated in the public schools of Como • In 1774, he became a professor at the Royal School of Como
While teaching, Volta made his first invention, the electrophorus: a device that produced static electricity
Volta began studying chemistry and discovered methane in the process • In 1779, he began teaching at The University of Pavia and continued to teach there for 25 years • In 1800, Volta invented his most famous invention: The Voltaic Pile
In 1810, Napoleon awarded Volta the title of Count for his work in the field of electricity • The Voltian Temple is a museum in Como that is dedicated to Volta’s research and inventions • Volta retired in 1819 and passed away five years later in March 1827 • In 1881, the electrical unit called the volt was named after Alessandro Volta
Luigi Galvani September 9, 1737- December 4, 1798 Appointed public lecturer in anatomy at the University of Bologna. Married Lucia Galleazzi Became President of the University of Bologna
Electricity and Animation Galvani's assistant touched an exposed sciatic nerve of the frog Alessandro Volta
Galvani vs Volta • Animal Electricity vs Heat Electricity • Galvani, who did not perceive electricity as separable from biology • Physical phenomenon • Volta coined the term "galvanism" • Creation of the first battery
Electrochemical Cell • Electrochemical cells are used in batteries in order to provide voltage and current. • Spontaneous chemical reactions occur • Contain two half cells
What is in a Electrochemical Cell? • Two or more Electrodes • Electrolytes • One salt bridge • One metal wire • Anodes • Cathodes
Electrode and Electrolyte • Electrodes are electrical conductors when connected to wiring can transfer electrons • An Electrolyte is a substance containing free movable ions that make the substance electrically conductive
Salt Bridge and a Wire • Salt Bridges allow ions to flow between the half-cells and prevents the solutions in the half-cells from mixing • The wiring connected to the electrodes allows the electrons to transfer between the half-cells without direct contact
Anodes and Cathodes • An anode is the electrode where oxidation occurs and that electrode looses electrons. • A cathode is the electrode where reduction occurs and that electrode gain electrons.
When chemical reactions in a Electrochemical cell occur one of the electrode undergoes oxidation while the second electrode undergoes reduction • Oxidation causes a electrode to lose ions and electrons • Reduction causes a electrode to gain ions and electrons
Galvanic Corrosion The electrochemical process in which one metal corrodes preferentially to another • Because Ions move from the Anode to the Cathode • Anodes corrode at a faster rate • Cathodes corrode at a slower rate
History of Alkaline Battery • Invented by Lewis Frederick Urry, in 1959. • A scientist at Eveready Battery Company, now known as Energizer • Account for 80% of manufactured batteries in the US • Toy car experiment • Alkaline vs. Zinc Carbon battery • longer shelf life as well as higher energy density
Parts of the Alkaline Battery • Container-A steel can houses the cells ingredients to form the cathode • Cathode= a manganese dioxide mixture and carbon. • Separator=non woven fibrous fabric which separates the electrodes
Parts of the Alkaline Battery • Anode=powdered zinc metal. Anodes are the electrodes that are oxidized • Electrodes=where the electrochemical reaction takes place • Electrolyte= a potassium hydroxide solution in water.
Parts of the Alkaline Battery • Collector=a brass pin in the middle of the cell that conducts electricity to the outside current • How an Alkaline Battery Works http://www.energizer.com/learning-center/pages/how-batteries-work.aspx
Explanation During discharge, Li+ carry the electrical current from the negative to positive electrode. When charging occurs, the charging circuit provides a higher voltage at the same polarity as the battery forcing the current to pass in the reverse direction. Li+ then become embedded in porous electrode material, this is know as intercalation.
Groups Four types- • Small cylindrical (solid body without terminals, such as those used in laptop batteries) • Large cylindrical (solid body with large threaded terminals) • Pouch (soft, flat body, such as those used in cell phones) • Prismatic (semi-hard plastic case with large threaded terminals, often used in vehicles' traction packs)
Uses LIBs are used in many products, including cell phone and laptop batteries. They are becoming more widespread because they can be recharged and produce a higher power output at a lower current. They also discharge at a much lower rate thus prolonging the battery life.
Inventor In 1979, John Goodenough’s innovation provided the positive electrode material which made LIBs possible. He is a UT Faculty member!
Future The evolution of the LIB continues, with issues such as safety, higher capacity, cost reduction, mass production being the subject of intensive research throughout the world. The development of new battery systems based on the LIB will spur another leap in innovation.
