Batteries

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Batteries

• Dry cells
• Wet cells
• Disposable/consumable
• Rechargeable

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Alessandro Volta the first battery

• In 1800, he built the first electrical pile, or
  battery a series of metal disks of two kinds,
  separated by cardboard disks soaked with acid or
  salt solutions. This is the basis of all modern
  wet-cell batteries. It was a tremendously
  important scientific discovery because it was the
  first method found for the generation of a
  sustained electrical current.

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How Volta got the idea

• The idea came from Luigi Galvani, an anatomist.
  Galvani was dissecting a (dead) frog when the
  frog's leg began to twitch. Galvani thought was
  because of some type of electrical action in the
  vicinity, such as lightning. Volta successfully
  duplicated the experiment on a clear day when
  there was no lightning.

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Voltas first battery

• Through experimentation, Volta realized that the
  two different metal objects holding the frog leg
  might be the source of the action. Over a period
  of several years he worked out that the wet
  muscle tissue conducted a current between the two
  different types of metals. Volta modified this
  effect to produce the first continuous flow of
  electric current. Around 1800, he invented a wet
  battery called a Voltaic Pile.

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Two kinds of batteries

• Dry Cellslike D, C, AAA, AA, 9 volt, etc.
• Not really dryinsides contain an ion
  transferring material which is a paste-like
  material.
• Wet cellslike car batteries
• Slosh around (sulfuric acid is the ion
  transferring material)

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2 kinds of dry cells

• Disposable/consumable The ones you replace when
  they are dead.
• Rechargeable The ones you plug into the wall
  outlet to recharge. More expensive to purchase
  but last a fairly long time (but they dont last
  forever!).
• Both can be re-cycled In East Brunswick, Best
  Buys, Office Depot, and Radio Shack are
  collection sites.

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Dry cells Carbon-Zinc Cells
Applications    Clocks    Communications
Equipment    Electronic Calculators   
Flashlights, Penlights    Measuring
Instruments    Remote Controls     Portable
Electronics Have mostly been replaced by
alkaline batteries.
                              
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Carbon-zinc battery
This arrangement is about the same for most
cylindrical batteries. The chemicals inside will
change, depending on type.
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Dry Cells Alkaline Cells

• These cells are similar to carbon-zinc but have
  much longer shelf life than carbon-zinc and
  perform better under drain and in cold weather.
  They use a different ion transfer paste that
  avoids the use of the zinc-corroding ammonium
  ions and does not produce any gaseous products.
  These are less likely to leak. Lew Urry developed
  the small alkaline battery in 1949. The inventor
  was working for the Eveready Battery Co. in
  Parma, Ohio. Alkaline batteries last five to
  eight times as long as zinc-carbon cells, their
  predecessors.

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Alkaline Batteries

• Applications
• Cameras
• Electric shavers
• Electronic calculators
• Electronic door locks
• Fire detectors

• High-power flashlights
• Pagers
• Strobes
• Tape recorders
• Toys
• Other cordless products

These are sold in both the disposable and
re-chargeable types.
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Wet Cell Lead-Acid Battery
The reaction of lead and lead oxide with the
sulfuric acid electrolyte produces a voltage. The
supplying of energy to an external resistance
(like to run a car) discharges the battery.
                                                  
                                                  
                      
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Wet Cell Lead-Acid Battery
                                                  
                                                  
                                                 
Most economical for larger power applications
where weight is of little concern. Preferred
choice for hospital equipment, wheelchairs,
emergency lighting, as well as car batteries.
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Other Dry Cells NiCd

• Nickel-Cadmium (NiCd) Used where long life,
  high discharge rate, and economical price are
  important. Main applications are two-way radios,
  biomedical equipment, professional video cameras,
  and power tools. Should be periodically
  discharged completely and then re-charged.
  Cadmium is toxic and environmentally unfriendly.
  Recycle!

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Other Dry Cells NiMH

• Nickel Metal Hydride (NiMH) Due to their
  increased capacity and energy density features,
  users can expect a longer time between charges
  and longer running time. NiMH contain no toxic
  metals. Applications include mobile phones and
  laptop computers. Experts feel that applying a
  full discharge once every three months seems
  right. Because of the NiMH batterys shorter
  cycle life, over-exercising (discharge/re-charge)
  is not recommended.

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Other Dry Cells Li-ion

• Lithium-ion (Li-ion) Fastest growing battery
  system used where high-energy density and light
  weight is of prime importance. This one is more
  expensive than other systems and must follow
  strict guidelines to assure safety. Not sold off
  the shelf but used in audio visual equipment,
  cellular phones, Notebook PC's, PDA's and handy
  terminals. Keep cool, but not frozen (do not
  store in a hot car), charge often avoiding deep
  discharges.

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Other Dry Cells Li-ion polymer

• Lithium-Ion Polymer (Li-ion polymer) A
  potentially lower cost version of the Li-ion and
  has similar chemistry. It enables very slim
  geometry and allows simplified packaging. Main
  applications are mobile phones.
• Lithium type batteries are constantly changing
  and improving as various internal chemicals are
  tried. Stay tuned!

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Take a battery quiz

• http//www.rediff.com/money/2005/may/26quiz.htm