Today's Batteries — They're (Much) Older than You Think

Last year I visited the Thomas Edison National Historical Park in New Jersey with my college roommate friend and my two teenage boys. In it are Edison’s home, laboratories and factory where the Genius of Menlo Park changed technology and history. The inventions that Edison invented are overwhelming. Edison was not just the most prolific inventor of all time; he was a manufacturer who successfully brought one idea after another into the marketplace. He's my hero.

Of the hundreds of exhibits we saw one stopped me dead in my tracks. While most visitors are drawn to the motion picture camera, phonograph and light bulb I was awe struck by a battery—a fully formed and functioning nickel-iron battery that Edison patented in 1901. It wasn't as if I didn't know that batteries go back more than a century. I knew that Alesandro Volta invented the first battery a full century before Edison in 1800. (He didn’t have a clue how it worked.) And we all know that electric cars reached their heyday in the early twentieth century.

Nevertheless, to see the highly developed battery in Edison’s factory capable of powering an electric car for about 20 miles was an eye opener. Today 20 miles may seem laughable but, had the gasoline vehicle never gathered traction (pun intended) and the battery increased its energy storage by a paltry 1% per year, we’d be driving electric vehicles that travel 2300 miles on a single charge.

I did a little reading (okay I Googled) into batteries and learned that the batteries we believe to be modern inventions are actually ancient when put into a Moore’s Law context. Here are some fun facts:

• The lead acid battery that starts our gasoline cars today actually predates the Civil War. I. Frenchman Gaston Plante invented it in 1859. Its man use was to power lights on trains when they stopped in a station.

• The nickel-cadmium (NiCd) battery that still powers most of our gadgets and toys today traces back to 1899 when Swede Waldemar Jungner created it as a wet cell (i.e. its electrolyte was a solution). It reached the U.S. nearly 50 years later in 1946.

• Edison didn’t invent the nickel-iron battery. That credit goes to the very same Waldemar Jungner. Jungner tried substituting cheaper iron for nickel in his NiCd battery but the formation of hydrogen gas killed his battery’s efficiency. Edison picked up Jungner’s patent and developed it to power Detroit Electric and Baker Electric cars. The Edison Storage Battery Company made and sold the NiFe battery from 1903 to 1975. It is still in use today and its lack of hazardous materials, like lead and cadmium, make it an environmentally friendly choice.

• The lithium ion battery that is the latest and greatest energy storage device goes all the way back to 1912 and famed chemist G.N. Lewis. Truth be told, that battery used neutral lithium and not the lithium ion in today’s batteries. The latter came out of several labs in the late seventies. The lithium atom is the third smallest (behind hydrogen and helium) so it’s no surprise that it carries them most amount charge per unit of weight.

Why this detour down Battery Memory Lane? All electrochemical sensors, whether they be amperometric (current producing) or potentiometric (voltage producing) are nothing more than batteries. Admittedly their output is too weak to power anything of significance but the oxidation and reduction reactions that drive their operation are the same oxidation and reduction reactions that drive batteries. Well almost all. The pH probe works through a charge difference between the hydrogen ions at the reference electrode and those at the working electrode. That makes it more like a capacitor. Hmmm. That sounds like the next big thing in energy storage—super-capacitors.