October 2004


A vehicle battery using “an inventive metal particulate anode” and a “bifunctional air electrode” may be recharged either by circulating the electrolyte containing the zinc particles and passing reverse current through them to recharge the battery, or the particles may be pumped out and replaced with previously recharged particles. This allows an electric vehicle to refuel at a zinc particle filling station. U.S. Patent # 5,441,820 describes this development and is available for licensing fromTechnology Transfer Department
E.O. Lawrence Berkeley National Laboratory
MS 90-1070
Berkeley, CA 94720
(510) 486-6467 Fax: (510) 486-6457
or send e-mail to: Technology Transfer Department
A list of other developments in batteries available for licensing from Berkeley Labs is available.

Other automotive battery applications:

Electric cars
Lithium-Metal-Polymer batteries for electric vehicles

Click on the links to see these new developments.

Announcement of a ‘Self-Charging’ battery
The Inventions Submission Corporation (ISC), of Pittsburgh PA has announced that two Fort Wayne IN inventors have created a self-charging replacement for rechargeable batteries. The invention “recharges without the use of special equipment or electrical current and can be produced in all standard battery sizes.”
Another entry to the “self-charging” field is shown in a US Patent Office Patent Application Publication 2006/0257734. To access these publications it is necessary to go to the USPTO home page and click on the Application Publication database.

Electric Cars
Electric cars discusses the use of batteries as motive power sources in electric vehicles, as well as temporary energy storage in hybrid and solar powered vehicles.

Lithium-Metal-Polymer Battery with ultra-thin film electrolyte

This Lithium-Metal-Polymer battery contains no liquid or paste electrolyte. The electrolyte is in the form of a polymer film, resulting in a lightweight battery that is rugged, required little maintenance, and can tolerate extremes of temperatures in service lives as long as 10 years.

Battery-operated water purifier

A new development offered by Proctor & Gamble, not yet on the market. It is low-power electrolysis technology that can remove pathogens from small or large quantities of water. The technology is offered for licensing through as a TechPak.

Uninterruptible power supply for a city? It takes a huge battery
Wouldn’t it be nice if we didn’t have to worry about the power going off suddenly with the loss of what you had been doing at the computer? It is called an uninterruptible power supply. You can buy one for your computer that will keep it going for some dozens of minutes. What if you were trying to provide power to a small city? Could you keep it going for 4 or more hours? Learn how by following the link above.

Valve-regulated Lead-Acid Batteries
Valve-regulated Lead-Acid batteries are more user-friendly than the type found in your automobile. They are welcome in the home or office. A new rugged case allows them to be shipped inside electronic equipment, where they can provide energy for uninterruptible power supplies. Read about new advances in energy density and service life.

Electric vehicles ‘refuel’ by pumping in recharged electrolyte
What do you do if you own an electric vehicle that has been driven too far for the amount of charge stored on its batteries? Do you drive to the nearest electrical plug-in and wait six hours for the batteries to charge? Suppose you could just drive into an electrolyte pumping station and say, “Fill her up!” This development allows for just that possibility.

Battery energy does not always remain quietly stored in the battery. Sometimes you must get that energy out in a hurry. Short bursts of power are required, for instance, when starting an automobile on a cold morning. Cold cranking requires high current from the battery. When you turn on the viewing screen of a digital camera, you also demand high current output from the camera’s battery.

The power used comes from stored energy
During every interval in which power is used, a quantity of energy is drained from the battery. That quantity of energy is equal to the amount of power, multiplied by the time the power flows. Energy has units of power and time, such as kilowatt-hours or watt-seconds. As the stored battery energy is used up, the available voltage and current drops lower and lower until finally the battery is exhausted. Then it is time to recharge or replace the battery. A good battery must supply two requirements. First, it must be able to meet the power demand by supplying adequate voltage and current when needed. Otherwise it is useless from the start. Secondly, there must be sufficient energy to last a long time, or else the battery must be economical, readily replaced, or easy to recharge.

Joules are units of energy or work
The Joule is the International Standard unit of energy defined as one watt-second. One watt-second of mechanical work is the work done by a force of one Newton (or 0.2247 pound) pushing through a one-meter distance. 3600 Joules are contained in one watt-hour, since an hour contains 3600 seconds,. Batteries are often rated in milliampere-hours instead of watt-hours. This battery rating can be converted to energy if the average voltage of the battery during discharge is known. For instance, a 3.6-volt Lithium-ion battery rated at 850 mAh will maintain a voltage of 3.6 volts with little variation during discharge. Multiply the voltage of 3.6 volts times 850 mAh to yield 3060 mA-volt-hours, or 3060 milliwatt-hours. 3.06 watt-hours equal 11016 watt-seconds or Joules. Compare this value to those found in the tables below.Joules may be converted to other familiar units using the numerical factors given below. Divide the number of Joules by 3.6 million to obtain kilowatt-hours. Divide the number of Joules by 1.356 to obtain the number of foot-pounds, a popular unit of work in the English system. Divide by 1055 to obtain the equivalent number of BTU (British Thermal Units). Divide by 4184 to obtain the number of food Calories! Yes, food Calories are energy, of course. This comparison does not put batteries in a good light compared to peanut butter. Two tablespoons of smooth peanut butter contain 191 Calories, or almost 800,000 Joules! It takes a huge battery to contain this much energy.

What battery type gives the most energy for the price?
In the table below we present the cost per Watt-hour, Specific Energy, that is Watt-hours per kilogram, Joules per kg, and the Energy Density, Watt-hours/liter for various types of batteries. It is not surprising that the well-known Lead-acid storage batteries head the list. Fine for use in our cars, but a little inconvenient in a laptop. And why are Alkaline long-life and Carbon-zinc batteries in the list? Aren’t they non-rechargeable? This was thought to be the case, previously, but now they can have their lifetimes extended by recharging. Ordinary alkaline cells may be recharged literally dozens of times using the new technology built into the Battery XtenderTM. Recharging alkaline, nickel-cadmium and nickel-metal hydride cells side-by-side in one automatic charger opens up new possibilities for battery selection economy.

$ per Wh
Wh/kg Joules/kg Wh/liter
Lead-acid $0.17 41 146,000 100
Alkaline long-life $0.19 110 400,000 320
Carbon-zinc $0.31 36 130,000 92
NiMH $0.99 95 340,000 300
NiCad $1.50 39 140,000 140
Lithium-ion $0.47 128 460,000 230

Costs of lithium-ion batteries are falling rapidly in the race to develop new electric vehicles. The $0.47 price per watt-hour above is for the Nissan Leaf automobile, and they predict a target cost of $0.37 per watt-hour. Tesla Automobiles uses a smaller battery pack, and they are optimistic about reaching a price of $0.20 per watt-hour in the near future.There is another type of battery that does not appear in the table above, since it is limited in the relative amount of current it can deliver. However, it has even higher energy storage per kilogram, and its temperature range is extreme, from -55 to +150°C. That type is Lithium Thionyl Chloride. It is used in extremely hazardous or critical applications such as space flight and deep sea diving.

The specifications for Lithium Thionyl Chloride are $1.16 per watt-hour, 700 watts/kg, 2,000,000 Joules/kg, and 1100 watt-hours per liter. For more information of Lithium Thionyl Chloride please contact Tadiran Batteries.
For more tables on energy storage, including the available storage in standard AAA, AA C, and D batteries, please follow the link to Battery Energy Tables. and for details on charging Alkaline batteries, please see Alkaline charging.

Our history of batteries begins with the Baghdad battery
Why was a battery required 2000 years ago?
In June, 1936, workers constructing a new railway near the city of Baghdad uncovered an ancient tomb. Relics in the tomb allowed archeologists to identify it as belonging to the Parthian Empire. The Parthians, although illiterate and nomadic, were the dominating force in the Fertile Crescent area between 190 BC to 224 AD. It is known that in 129 BC they had acquired lands up to the banks of the Tigris River, near Baghdad.

Among the relics found in the tomb was a clay jar or vase, sealed with pitch at its top opening. An iron rod protruded from the center, surrounded by a cylindrical tube made of wrapped copper sheet. The height of the jar was about 15 cm, and the copper tube was about 4 cm diameter by 12 cm in length. Tests of replicas, when filled with an acidic liquid such as vinegar, showed it could have produced between 1.5 and 2 volts between the iron and copper. It is suspected that this early battery, or more than one in series, may have been used to electroplate gold onto silver artifacts.

A German archeologist, Dr. Wilhelm Konig, identified the clay pot as a possible battery in 1938. While its 2000-year old date would make it the first documented battery invention, there may have been even earlier technology at work. Dr. Konig also found Sumerian vases made of copper, but plated with silver, dating back to 2500 BC. No evidence of Sumerian batteries has been found to date.

1747 — Principle of the telegraph discovered, but not battery-powered.
In 1747 Sir William Watson demonstrated in England that a current could be sent through a long wire, using the conduction through the earth as the other conductor of the circuit. Presumably the current was from an electrostatic discharge, such as from a Leyden jar charged with high voltage. People at that time knew how to generate electrostatic voltages by rubbing dissimilar materials such as glass and fur together. Then in 1753 a certain C.M. in Scotland devised a signaling machine that used an insulated wire for each letter of the alphabet. At the sending end an electrostatic charge was applied to the selected wire, and a pith ball jumped at the receiving end in response to the voltage.

1786 — Luigi Galvani notices the reaction of frog legs to voltage
He was remarkably close to discovering the principle of the battery, but missed it. He thought the reaction was due to a property of the tissues. He used two dissimilar metals in contact with a moist substance to touch dissected frog legs. The resulting current made the muscles in the frog legs twitch. Luigi Galvani made many more important discoveries later, when the relationship between magnets and currents became known. The galvanometer is named for him. It is a moving coil set in a permanent magnetic field. Current flowing through the coil deflects it and an attached mirror, which reflects a beam of light. It was the first accurate electrical measuring instrument.

1800 — Alessandro Volta publishes details of a battery
That battery was made by piling up layers of silver, paper or cloth soaked in salt, and zinc. Many triple layers were assembled into a tall pile, without paper or cloth between zinc and silver, until the desired voltage was reached. Even today the French word for battery is ‘pile’ (English pronunciation “peel”.) Volta also developed the concept of the electrochemical series, which ranks the potential produced when various metals are in contact with an electrolyte. How handy for us that he was well known for his publications and received recognition for this through the naming of the standard unit of electric potential as the volt. Otherwise, we would have to ask “How many galvans does your battery produce?” instead of asking “how many volts does your battery produce?”

1820 — The Daniell Cell
The Voltaic Pile was not good for delivering currents for long periods of time. This restriction was overcome in the Daniell Cell. British researcher John Frederich Daniell developed an arrangement where a copper plate was located at the bottom of a wide-mouthed jar. A cast zinc piece commonly referred to as a crowfoot, because of its shape, was located at the top of the plate, hanging on the rim of the jar. Two electrolytes, or conducting liquids, were employed. A saturated copper sulphate solution covered the copper plate and extended halfway up the remaining distance toward the zinc piece. Then a zinc sulphate solution, a less dense liquid, was carefully poured in to float above the copper sulphate and immerse the zinc. As an alternative to zinc sulphate, magnesium sulphate or dilute sulphuric acid was sometimes used. The Daniell Cell was one of the first to incorporate mercury, by amalgamating it with the zinc anode to reduce corrosion when the batteries were not in use. We now know better than to put mercury into batteries. This battery, which produced about 1.1 volts, was used to power telegraphs, telephones, and even to ring doorbells in homes for over 100 years. The applications were all stationary ones, because motion would mix the two electrolyte liquids. The battery jars have become collectors items, with prices ranging for $4 to $44. Check them out on

1859 — Lead Acid — the Planté Battery
Raymond Gaston Planté made a cell by rolling up two strips of lead sheet separated by pieces of flannel, and the whole assembly was immersed in dilute sulphuric acid. By alternately charging and discharging this cell, its ability to supply current was increased. An improved separator was obviously needed to resist the sulphuric acid.

1866 — The Leclanché carbon-zinc battery
The first cell developed by Georges Leclanché in France was a wet cell having its electrodes immersed in a liquid. Nevertheless, it was rugged and easy to manufacture and had a good shelf life. He later improved the battery by substituting a moist ammonium chloride paste for the liquid electrolyte and sealing the battery. The resulting battery was referred to as a dry cell. It could be used in various positions and moved about without spilling. Carbon-zinc dry cells are sold to this day in blister packages labeled “heavy duty” and “transistor power”. The anode of the cell was zinc, which was made into a cup or can which contained the other parts of the battery. The cathode was a mixture of 8 parts manganese dioxide with one part of carbon black, connected to the positive post or button at the top of the battery by a carbon collector rod. The electrolyte paste may also contain some zinc chloride. Around 1960 sales of Leclanché cells were surpassed by the newer alkaline-manganese batteries.

1881 — Camille Faure’s Lead Acid Battery — suitable for autos
Camille Faure’s acid battery used a grid of cast lead packed with lead oxide paste, instead of lead sheets. This improved its ability to supply current. It formed the basis of the modern lead acid battery used in autos, particularly when new separator materials were developed to hold the positive plates in place, and prevent particles falling from these plates from shorting out the positive and negative plates from the conductive sediment.

1898 to 1908 — the Edison Battery
Thomas Edison, the most prolific of all American inventors, developed an alkaline cell with iron as the anode material (-) and nickelic oxide as the cathode material (+). The electrolyte used was potassium hydroxide, the same as in modern nickel-cadmium and alkaline batteries. The cells were well suited to industrial and railroad use. They survived being overcharged or remaining uncharged for long periods of time. Their voltage (1 to 1.35 volts) was an indication of their state of charge.

1893 to 1909 — the Nickel-Cadmium Battery
In parallel with the work of Edison, but independently, Jungner and Berg in Sweden developed the nickel-cadmium cell. In place of the iron used in the Edison cell, they used cadmium, with the result that it operated better at low temperatures, self-discharged itself to a lesser degree than the Edison cell, and could be trickle-charged, that is, charged at a much-reduced rate. In a different format and using the same chemistry, nickel-cadmium cells are still made and sold.

1949 — the Alkaline-Manganese Battery
The alkaline-manganese battery, or as we know it today, the alkaline battery, was developed in 1949 by Lew Urry at the Eveready Battery Company Laboratory in Parma, Ohio. Alkaline batteries could supply more total energy at higher currents than the Leclanché batteries. Further improvements since then have increased the energy storage within a given size package.

1950 — The zinc-mercuric oxide alkaline battery by Ruben
Samuel Ruben (an independent inventor) developed the zinc-mercuric oxide alkaline battery, which was licensed to the P.R. Mallory Co. P.R. Mallory Co. later became Duracell, International. Mercury compounds have since been eliminated from batteries to protect the environment.

1964 — Duracell is formed (incorporated)