Ethanol Use in Battery Production for Electric Vehicles
What is Ethanol?
Ethanol is a clear, colorless liquid with the chemical formula C2H6O, and is commonly referred to as alcohol, ethyl alcohol, and grain alcohol. Ethyl alcohol is a volatile and flammable liquid and has a wide variety of industrial and home applications due to its miscibility with water and other organic compounds. Most ethanol produced in the United States is produced from starchy crops such as corn via the fermentation of sugars by yeast or ethylene hydration processes.
An Overview of EV Batteries
In recent years, there is a big push for greener more sustainable energy. This can be seen in the popularity of EVs (electric vehicles) on the road today. Increasingly, manufacturers are requiring deposits in advance of estimated delivery dates while ICE (internal combustion engines) are being replaced by the more environmentally friendly vehicles.
What makes electric vehicles better for the environment? The main reason is that they emit fewer greenhouse gases such as NOx, CO2, and chlorofluorocarbons which are believed to be the culprits in causing climate change. In addition, they can cause harmful effects to human health from smog and air pollution. Because electric cars do not have an internal combustion engine, no carbon dioxide is being emitted into the atmosphere, which greatly increases the quality of the air we breathe.
While this sounds great, we must consider the life cycle of the batteries that power EVs, which includes how the batteries are produced. Lithium-ion batteries are the most commonly used batteries in electric vehicles. These batteries are composed of elements such as carbon, a metal oxide, and lithium salt. Cobalt is used in these batteries to increase their life and energy density. The positive and negative electrodes that these elements have are combined with an electrolyte, which then produces an electric current that enables the battery to power an EV. When the lithium ion is removed from the cathode (the positive end), the ion is left with a positive charge, which causes cobalt to change its oxidation state from the 3+ to the 4+, to remain electrically neutral. The issue lies in the sourcing of the materials. Mining cobalt causes environmental degradation and pollution of water supplies and recycling of these batteries is a challenge.
Use of Ethanol in EV Battery Production
The cobalt based cathodes are typically chosen due to the microstructure it is able to form, however, scientists have recently found a promising alternative to cobalt. They have identified that using ethanol as a solvent to alter the microstructure of a substance called PTO (Pyrene-4,5-,9,10-tetraone) makes it so that it can be used as the cathode in a battery in place of cobalt. Scientists found that the rearrangement of the microstructure of PTO using ethanol has significantly increased the energy density compared to cobalt, as well as reduced the amount of carbon footprint from mining the transition metals. This alternative could further improve the sustainability of EVs.
