Could anodes made from mushrooms revolutionize the batteries of the future? Every battery has two electrodes — an anode and a cathode. They are the terminals that connect the battery to the outside world. All the electrons that flow into or out of a battery must pass through one or the other. Much of the research into higher performance batteries is concentrated on improving the electrodes so that electrons can flow more efficiently.
The batteries used in electric cars today typically have an anode made from synthetic graphite, which is expensive because it requires extensive purification in a processes that is harmful to the environment. With the anticipated increase in batteries needed for electric vehicles and electronics, a cheaper and sustainable source to replace graphite is needed.
It will take nearly 900,000 tons of natural raw graphite to fabricate the anodes for the six million electric vehicles expected to be built by 2020. All that graphite will need to be treated with harsh chemicals, including hydrofluoric and sulfuric acids, in a process that creates large quantities of hazardous waste. The European Union projects this process will be unsustainable in the future.
Researchers at the University of California at Riverside Bourns College of Engineering think they have the answer, according to Science Daily. They have created a new type of lithium-ion battery anode using portabella mushrooms, which are inexpensive, environmentally friendly, and easy to produce. They got interested in mushrooms because they are highly porous and have lots of small spaces for electrons to pass through.
The lowly mushroom has been receiving lots of attention from innovators lately. A company by the name of Ecovative is using them to grow building materials with high insulating power that are also environmentally friendly.
That porosity is important for batteries because it creates more space for the storage and transfer of energy, a critical component to improving battery performance. In addition, the high potassium salt concentration in mushrooms creates more pores over time, gradually increasing its capacity. A conventional anode allows lithium to fully access most of the material during the first few cycles but capacity degrades from electrode damage from that point on. The mushroom carbon anode technology could enable a battery that actually perform better as it ages.
“With battery materials like this, future cell phones may see an increase in run time after many uses, rather than a decrease, due to apparent activation of blind pores within the carbon architectures as the cell charges and discharges over time,” said Brennan Campbell, a graduate student in the Materials Science and Engineering program at UC Riverside.
So, UC Riverside scientists are hinting at batteries that are more powerful, cost less, are more environmentally friendly, and last longer? That sounds like wonderful news for electric car fans.