The search for a better battery replacement is on, but with battery limitations gating not just consumer electronics, but clean energy initiatives and the electric car industry as well, there is urgency. The push has activated a variety of new battery concepts, which will likely become more common in the future.
Environmentally-friendly liquid-metal batteries could help lead to safe, inexpensive storage of renewable energy for power grids. According to researchers, this new type of battery could have a longer cycle life, and much greater power than any current rechargeable battery.
The sun and wind are variable sources of power, and utility companies, for example, want massive rechargeable battery farms that can store the surplus energy for when the sun goes down and the wind doesn’t blow. However, as with many rechargeable batteries, safety is a concern. Many of these devices contain toxic, corrosive, or flammable components, or require searing-hot operating temperatures.
To prevent this, researchers have created a battery that uses environmentally-friendly liquids to store and release energy. The new battery possesses a cathode made of water-soluble iodide and triiodide, a watery electrolyte containing lithium or sulfur ions that the cathode dissolves in, a solid anode made of polyimide, and a polymer membrane that separates the anode and the cathode to allow ions to diffuse across it. When the battery is discharging electricity, the process reverses. Better yet, this new battery has a long life of 50,000 cycles.
With metal-air batteries, the metal electrodes react with oxygen in the air, instead of a liquid, to produce an electrical current. Currently, the best materials for the electrode appear to be lithium and sodium, but aluminum and zinc have also been researched.
Although the development of the Li-battery is still in its early stages, the technology holds a strong promise, with energy that’s five to 10 times higher than Li-ion batteries. This is specifically attractive to the electric car industry. Impressively, the high specific energy of Li-air batteries translates to 1,000 miles of range compared to the average 125 miles on Li-ion batteries.
Graphene car batteries
Graphene batteries are believed to be a large part of the future. One company, Graphenano, developed a battery called Grabat, and it could offer electric cars a driving range of up to 500 miles on a single charge. According to the company, the batteries can be fully charged in just a few minutes, and can charge and discharge 33 times faster than Li-ion batteries.
The capacity of the 2.3-V Grabat is huge, with around 1000 Wh/kg, which compares to Li-ion’s current 180 Wh/kg. These batteries are predicted to be available midway through 2016.