1. Understanding Batteries-Concepts for Teaching
By Harry T. Roman

2. Batteries and Electrochemistry
Battery operation is governed by the laws of electrochemistry

3. Types of Batteries Two basic types of batteries:
Primary batteries can be used only once and then are totally discharged and discarded.
Secondary batteries are capable of being re-charged; their chemical reactions can be reversed- examples…cell phones, car batteries.

4. Typical Primary Batteries

5. Typical Secondary Battery

6. How Batteries/Cells Work
There are three main components of a battery: two terminals made of different chemicals (typically metals), the anode and the cathode; and the electrolyte, which separates these terminals.
The electrolyte is a chemical medium that allows the flow of electrical charge between the cathode and anode.
When a device is connected to a battery — a light bulb or an electric circuit — chemical reactions occur on the electrodes that create a flow of electrical energy to the device.  

7. Dry Cell Cross Section
Dry cell batteries are easy to make, modular, and have excellent quality assurance characteristics.
They are easily distributed and sold everywhere in large numbers.

8. What are Batteries/Cells Like?
Think of a hydroelectric dam:
The dam height represents battery/cell voltage.
The amount of water behind the dam is the capacity or total energy available.
How much water comes out at a time [the battery draw] is the power expended. The more draw, the more rapidly the water is depleted.
Bigger batteries of equal voltage have more total energy available.

9. Early Battery History
1800: The Voltaic Pile, Alessandro Volta, the first true battery of zinc and copper plates separated by brine soaked cloth. 
1820: The Daniel Cell Battery 
1838: The Porous Pot Cell 
1859: Lead Acid Battery 
1866: The Leclanché Cell, a Carbon-Zinc battery –the first dry cell battery [like ours today!]

10. Early Battery History Cont’d
1899: The Nickel-Cadmium Battery 1899: Waldmar Jungner invented the first nickel-cadmium rechargeable battery.
1901: The Edison Battery-- nickel-iron batteries originally intended for electric vehicle use; but later used in many industry applications. The rechargeable alkaline storage battery was invented by Thomas Alva Edison.
1912: Lithium and Lithium-Ion Batteries

11. Multiple Cell Batteries
12-Volt Car Batteries-are made of six 2.0 volt cells
9-Volt Batteries – are made of six 1.5 volt cells

12. Car Batteries
Car batteries can still be largely wet cell designs-although many are gel-type cells now.
Large banks of storage batteries can still be wet cell affairs, It all depends on costs and design characteristics.

13. Edison’s Batteries
Thomas Edison invented and widely sold his rugged nickel-iron storage battery—which was a wet cell battery.
Today, companies are still making that kind of battery

14. Tesla Solar Battery Pack

15. Large Scale Battery Back-up

16. Wet Cell Batteries
Before dry cells, batteries were made of single cells built in series [and later parallel] to provide power and capacity for use in many applications.

17. Cu-Zn Test Cell Performance
Electrolyte Volts
Saltwater
TIDE detergent
Downy fabric softener .89
Windex
Bleach
Soda
Gatorade

18. Play Doh Electrolyte Metal Electrodes Volts Cu-Fe .24 Cu-Zn .78
Carbon-Zn [pencil lead]
Ni-Fe [Edison battery]
Cu-Al
Cu-Tin
Fe-Tin
Fe-Al
Tin-Al

19. Play Doh Electrolyte Cont’d
Metal Electrolyte Volts
Tin-Zn
Ni-Al
Ni-Tin
Ni-Cu
Carbon-Tin
Carbon-Al
Carbon-Fe

20. Play Doh Single Cell [Cu-Zn]

21. Play Doh --2 cells in series

22. Play Doh--3 cells in series

23. Play Doh -- 4 cells in series