The battery series will present five infographics to inform investors how batteries work, the players in the market, the materials needed to build batteries and how future battery developments may affect the world. This is Part 1, which looks at the basics of batteries and the history of battery technology.
Today, how we store energy is just as important as how we create it.
Battery technology already makes electric cars possible, as well as helping us store emergency power, fly satellites and use portable electronic devices. But tomorrow, could you be boarding a battery-powered airplane, or be living in a city powered at night by solar energy?
Batteries convert stored chemical energy directly into electrical energy. Batteries have three main components:
(-) Anode: The negative electrode that gets oxidized, releasing electrons.
(+) Cathode: The positive electrode that is reduced, by acquiring electrons.
Electrolyte: The medium that provides the ion transport mechanism between the cathode and anode of a cell. It can be liquid or solid.
At the most basic level, batteries are very simple. In fact, a primitive battery can even be made with a copper penny, galvanized nail (zinc) and a lemon or potato.
The evolution of battery technology
While creating a simple battery is quite easy, making a good battery is very difficult. Balancing power, weight, cost and other factors involves managing many trade-offs, and scientists have worked for hundreds of years to get to today’s level of efficiency.
Here’s a brief history of how batteries have changed over the years:
Voltaic pile (1799)
Italian physicist Alessandro Volta, in 1799, created the first electrical battery that could provide continuous electrical current to a circuit. The voltaic pile used zinc and copper for electrodes with brine-soaked paper for an electrolyte.
His invention disproved the common theory that electricity could only be created by living beings.
Daniell cell (1836)
About 40 years later, a British chemist named John Frederic Daniell would create a new cell that would solve the “hydrogen bubble” problem of the voltaic pile. This previous problem, in which bubbles collected on the bottom of the zinc electrodes, limited the pile’s lifespan and uses.
The Daniell cell, invented in 1836, used a copper pot filled with copper sulphate solution, which was further immersed in an earthenware container filled with sulphuric acid and a zinc electrode. The Daniell cell’s electrical potential became the basis unit for voltage, equal to one volt.
The lead-acid battery was the first rechargeable battery, invented in 1859 by French physicist Gaston Planté.
Lead-acid batteries excel in two areas: they are very low-cost and they can also supply high surge currents. This makes them suitable for automobile starter motors even with today’s technology and it’s part of the reason $44.7 billion of lead-acid batteries were sold globally in 2014.
Nickel cadmium (1899)
Nickel cadmium batteries were invented in 1899 by Waldemar Jungner in Sweden. The first ones were “wet cells” similar to lead-acid batteries, using a liquid electrolyte.
Nickel cadmium batteries helped pave the way for modern technology but they are being used less and less because of cadmium’s toxicity. The batteries lost 80% of their market share in the 1990s to batteries that are more familiar to us today.
Alkaline batteries (1950s)
Popularized by brands like Duracell and Energizer, alkaline batteries are used in regular household devices from remote controls to flashlights. They are inexpensive and typically non-rechargeable, though they can be made rechargeable by using a specially designed cell.
The modern alkaline battery was invented by Canadian engineer Lewis Urry in the 1950s. Using zinc and manganese oxide in the electrodes, the battery type gets its name from the alkaline electrolyte used—potassium hydroxide.
Over 10 billion alkaline batteries have been made in the world.
Nickel-metal hydride (1989)
Similar to the rechargeable nickel cadmium battery, the nickel-metal hydride formulation uses a hydrogen-absorbing alloy instead of toxic cadmium. This makes it more environmentally safe—and it also helps increase the energy density.
Nickel-metal hydride batteries are used in power tools, digital cameras and some other electronic devices. They also were used in early hybrid vehicles such as the Toyota Prius.
The development of nickel-metal hydride spanned two decades and was sponsored by Daimler-Benz and Volkswagen AG. The first commercially available cells were in 1989.
Sony released the first commercial lithium-ion battery in 1991.
Lithium-ion batteries have high energy density and a number of specific cathode formulations for different applications. For example, lithium cobalt dioxide (LiCoO2) cathodes are used in laptops and smartphones, while lithium nickel cobalt aluminum oxide (LiNiCoAlO2) cathodes, also known as NCAs, are used in the batteries of vehicles such as the Tesla Model S.
Graphite is a common material for use in the anode and the electrolyte is most often a type of lithium salt suspended in an organic solvent.
The rechargeable battery spectrum
There are several factors that could affect battery choice, including cost. However, here are two of the most important factors that determine the fit and use of rechargeable batteries specifically:
Think of specific energy as the amount of water in a tank. It’s the amount of energy a battery holds in total. Meanwhile, specific power is the speed at which that water can pour out of the tank. It’s the amount of current a battery can supply for a given use.
And while today the lithium-ion battery is the workhorse for gadgets and electric vehicles, what batteries will be vital to our future? How big is that market? Find out in the rest of the battery series. Parts 2 through 5 will be released throughout the summer.
Posted with permission of Visual Capitalist.