Zinc chloride battery vs. alkaline
Image by Flickr.com, courtesy of Windell Oskay
The feel-good commercials for Duracell and the often-humorous ones with the Energizer bunny on U.S. TV reveal the dominance of the alkaline battery in battery-powered devices today, ranging from smoke detectors to remote-control vehicles.
Construction workers in Baghdad discovered a second century tomb in 1936 that contained clay pots sealed with pitch around an iron rod. In 1938, Dr. Wilhelm Konig determined that it could have been the first battery. The "Mythbusters" cable TV show actually built functioning replicas that were producing 1.5 to 2 volts of power.
In 1820, British scientist John Daniell developed a battery that employed zinc sulphate and copper sulphate liquids suspended between two metal plates, producing about 1.1 volts and providing power to phones, doorbells and other devices for the next 100 years.
Zinc Chloride Batteries
Carbon batteries use zinc chloride as an electrolyte solution to carry the current between the cathode (negative pole) consisting of manganese dioxide and the anode (positive pole) made of zinc.
In an alkaline battery, the cathode is made of manganese dioxide, while the anode is made of powdered zinc metal, and the electrolyte is a potassium hydroxide solution. These batteries are typically not rechargeable and discarded after depletion.
Zinc chloride batteries supply 50 per cent more energy than zinc carbon batteries, but alkaline batteries produce 500 per cent more power. This gives alkaline batteries the edge against zinc chloride, especially in high drain devices.
- Image by Flickr.com, courtesy of Windell Oskay