Since the introduction of ultracapacitors a new type of battery entered the scene. An Ultracapacitor, being a capacitor with a much bigger ability to store electric charge, is in fact a type of battery.
The way an ultracapacitor stores more power is by using electrolyte, like in a battery. But unlike in a battery, the voltage is always kept to low to cause actual chemical reactions. In a normal battery a chemical reaction frees electrons on the negative side, and accepts them on the positve side. In an ultracapacitor only the orientation of the molecules changes,so the positive electrode gets surrounded by the negative side of the molecule, and the negative electrode by the positive side of the molecule. This increases the amount of charge one can store in the electrodes immensly. The molecules that orient would like to spring back to chaos, and this is they way energy is stored.
Ultracapacitor capacity can be increased by increasing the surface area of the electrodes, so more molecules can hug up against them. This is not easy with metals, so a foamy lead electrode would not work, because the lead dissolves and accumulates back and would not keep its shape. A lead acid battery is thus limited in its efficiency. A better lead acid battery can be made by using one electrode made of activated carbon. Activated carbon is carbonized organic material that has had a special heat treatment causing it to become enormously porous, having a very large surface area. A few pellets can have the surface area of a footbal field. Activated carbon is reactive, and because a chemical reaction depends on the apparend concentration of reagens, its large surface area causes any chemical to be neutralized by it.
Activated carbon
Carbon is also a reasonable conductor. So activated carbon electrodes are very promising to increase the capacity of ultracapacitors and batteries. One challenge is to keep the carbon connected to the output part of the battery. Otherwise there would be many ‘stranded’ grains of activated carbon not adding to the output of the battery. One way to change this is to try to grow nanowires. Another way is to use organic material that are already thin and fibrous, like cotton.
Battery with carbonized activated cotton electrodes has to use an electrolyte that does not react with the electrods. It might have to be an ultracapacitor, but it could also use an electrolyte with two stabile molecules that could switch back and forth based on charge added or removed. Apparently this is possible with Litium, which in Lithium-Ion batteries forms a complex with Oxygen. It can also react with Oxygen, so it could burn, but in the batteries it doesn’t. It seems the Double Carbon Batteries use the same reaction, only without the oxygen, but with carbon. The positive Lithium ions simply stick to the positive electrode as electrons are taken from it during chargeing.
The cost of these batteries could be very low. Based on Lithium they would be designed for use in cars, extending the range to 300 miles for cars that now reach 100 miles. With other chemistry/electrolytes they could be even cheaper. Manufacturing can also be replicated easily. The only challenge is restrictive royalties and fianceing of production plants. But with a thought out design it can mean cheaper electricity storage, enabling more renewable energy use and less investment in wastefull centralized electricity production and infrastructure.