Tag Archives: Batteries

Can electric cars be actually worse for the environment?

Electric cars are not as green as people think according to several scientific studies. Although they are popularly known as being eco-friendlier than using gas fuel, in the long run it might contribute even more to global warming. However, this new technology is still under development so it is early for scientist to be certain about the long term effect.

There are several aspects to take into account when determining why electric batteries might generate more contamination than gas motors. While using the car might not emit any greenhouse gas: making their batteries, recycling its chemicals, and the source of electricity that powers the car contribute in such extent that in the overall it might be more harmful to the environment than gas fueled cars if not assessed.

Most electric car batteries, as in Tesla, are lithium and cobalt based which require much more energy for their production than a conventional car motor. The energy required for mining these compounds is higher than to extract oil. Additionally, chemical compounds used for their manufacturing release greenhouse gases that contribute equally as CO2 to global warming. However, the emission caused by extracting these metals is substantially lower than the CO2 emitted by cars. Still it accounts for the fact that manufacturing electrical cars contribute to global warming.

Moreover, chemicals used for electrical batteries are very toxic for the environment if not properly recycled. While this may not affect us today because regular cars have not been completely replaced by electric cars, in the future it may be a problem when the amount of worn batteries are substantially higher. When this replacement happens, there would be a greater amount of people with cars since the cost of electricity to charge a car is not as high as gas, making it more affordable for people to own one. At the beginning of the transition this does not pose a major threat, but it should be taken into account for the future when the amount of worn batteries needed for handling as toxic waste or recycle is much greater.

Most importantly, the greatest concern for environmental impact of electrical cars is the source of energy that powers them. If the country you live in derives its energy from burning oil and coal, the CO2 emission it produces is significantly greater than that of a regular car during its lifetime, posing a greater threat for global warming. As the transition towards electrical cars takes place, there would be greater energy production demand, so much more needs to be generated. If this energy is not from an ecological source, the pollution generated to supply this amount of energy is significantly higher, making electric cars actually much more contaminant than using gas-powered cars.

In the overall, electric cars appear to be better for the environment than regular cars but that does not mean that they don’t contribute to global warming. Moreover, if is not well assessed it can actually be more harmful for the environment in the long run.

Andrea Olaizola

No More Battery Explosions!

Remember how recently Samsung had to discontinue their sales of Galaxy Note 7 because of their lithium battery explosion? It had been quite an issue for the world, Samsung being one of the top companies for mobile phone sales.

Battery Explosion of Samsung Galaxy Note 7, Image from flickr

However, there is no more need to worry about your phone exploding in your hands thanks to Dr. Suo and his team – they have found a way to make both safe and high-voltage lithium battery.

Originally, for high-voltage batteries (>3.0V), flammable and non-aqueous toxic electrolytes were used. They had a huge downside of causing safety and environmental concerns, especially in large-scale applications. The idealistic non-flammable and green aqueous electrolytes were too low in voltage (1.50V), reduction of water leading to hydrogen evolution being the main problem.

Suo and his team came up with another type of electrolyte called a water-in-bisalt” (WIBS) electrolyte that fixes the problem at a wide 3.0V stability window. Suo says, “In such a concentrated environment of electrolyte, the salt anion decomposes on the anode, forming the solid electrolyte interphase (SEI) before the hydrogen evolution. SEI formation in aqueous electrolytes decreases the amount of water molecules around the Li+ molecules, reducing the electrochemical activity of water. This maximizes the full cell energy density, as Li+ is a limited resource within the battery cell.”

In short, the SEI layer formation in the WIBS electrolyte enhances the battery power and ability to repeat the cycle, as it prevents any side reactions occurring at the anode.

The team has concluded that the electrochemical coupling of electrolyte of LiMn2O4 and C-TiO2 through the carbon coating and super-concentrated aqueous electrolyte could stabilize the cycling ability of the lithium battery.

Carbon, being catalytically inert, introduces extra kinetic barrier to water splitting; and being highly conductive, it also reduces charge transfer resistance and polarization. Also, WIBS electrolyte being high in ionic density, it terminates hydrogen evolution and enhances the formation of more protective SEI.

This is the first time to propose the new non-hazardous electrolyte battery. With this, there could be many more improvements made to commercial applications from small items like cellphones, to big items like cars. Despite this new proposed electrolyte, there still needs to be more work and refining done to the power and energy density of the new battery before it can be commercialized. Hopefully in a few years the world could be using safe, non-explosive phones.

Clair Yoon