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Emerging power sources of electric vehicles: Part 2
Updated: Jan 28, 2022
“In order to have clean air, you have to go electric”
- Elon Musk
Modern car manufactures market electric vehicles (EV) with green label and promises it to be the future of transport. Assertion is made on zero carbon dioxide emissions coming from EVs. The large-scale deployment of EV’s is widely regarded as a suitable strategy to address major sustainability shortfalls of the transport sector, namely its contribution to urban air pollution and anthropogenic climate change and its dependence on nonrenewable fossil fuels. The prime technological requirements is the advancement of lithium ion batteries(LIBs) to satisfy everyday habits of the society for relinquishing the well-established petrol powered vehicles.
Comparing EV’s with ICE’s:
Electric cars are predicted to be the next disruptive market force for transportation and technology. They have the potential to revolutionize how energy is used, created and redirected. The advent of electric cars has called for an improvement in overall energy usage and generation. They have shown how important it is to find alternate sources of fuel. EV’s indeed present several advantages over conventional passenger cars equipped with an internal combustion engine vehicle (ICEV).
EV’s do not exhibit tailpipe emissions.
EV’s are 75 percent efficient at turning input energy into moving energy, while gas-powered vehicles with internal combustion engines (ICE) are only 25 percent efficient.
Electric cars, having less parts to funnel energy through, undergo less energy conversion. This results in less energy loss compared to gas-powered engines.
Even cooler, electric car brakes don’t function the same way that gas-powered car brakes do: they have regenerative braking. This allows the car to charge the battery while braking.
Environmental concern of EV’s:
EV’s have been promoted for the past decade, there has also been criticism that they may shift emissions from vehicle use to vehicle production and electricity generation, thereby potentially increasing environmental and health impacts elsewhere. In fact, the electric vehicle is a paragon emphasizing the need of assessing a product’s impact over the life cycle instead of the operation phase only.
Moreover, the large diversity in economically viable electricity generation renders the environmental performance of electric vehicles case specific and sensitive. This situation has led to an intensified scientific debate about the environmental impacts of EVs.
During production of LIBs a lot of rare earth metals are mined from deep mines and their extraction takes a serious toll on the environment. A 2018 International Council on Clean Transportation(ICTT) report illustrates, that battery manufacturing countries has a much higher level of impact on emissions. The pollution created through the extraction process and production of batteries remains on par or slightly higher than the manufacturing process of petrol or diesel-based engines, over petrol and diesel powered cars. Whilst ICEVs have been steadily reducing their emissions since 2000, electric vehicles still have a marked edge by producing close to no running emissions.
Additionally, as EV’s become more common and manufacturing becomes more widespread, battery recycling will be more efficient and reduce the need to extract new materials, therefore lessening the reliance on mining and production of new batteries.
How we can make our batteries better for the environment:
Mining & Refining:
During any battery’s lifetime, the report says, some of the worst environmental impacts come from mining and refining. Metals like cobalt and nickel are essential for conducting electricity in many batteries, but digging them out of the ground leaves behind waste that can leak toxic substances into surrounding areas.
Once these materials are mined, workers must then extract them from the rocks they’re embedded in, a process that emits large amounts of the pollutant sulphur oxide. To mitigate these harms, the report calls for more reuse and recycling of battery materials.
Researchers are working to develop higher density batteries, which the report points to as another helpful solution. By storing more energy in a smaller space, such batteries use less metal. And compared with batteries that are less dense, they can power a device for a longer stretch of time, so, for example, that electric vehicles can travel farther before needing to be recharged.
Limiting Energy Loss:
Limiting energy loss, can also have big returns. Rechargeable batteries are able to unload most, but not all, of their energy to power phones, cars, and other devices. The remaining portion is lost, with the amount varying: Standard lead-acid batteries waste 20 to 30 percent of their energy over a lifetime, while lithium-ion batteries have energy loss closer to 10 percent. Improving efficiency by even small amounts can cut down on the environmental harms of producing electricity to charge batteries.
Development & Invention:
Many battery technologies are in development, and the report spotlights three of them as case studies:
Solid-state lithium batteries replace the electrolyte, a key component of the battery that’s typically liquid, with solid ceramic or polymer material.
The report says that these batteries will be safer and last longer, but it will be at least a decade before they become commercially available.
Redox flow batteries store energy differently than conventional alternatives. They’re not as efficient but they last longer, which would ease demand for the natural resources and polluting production processes that batteries rely on.
Researchers are working to reduce the cost and size of redox flow batteries so they can reach their full potential.
Printed batteries have already found some commercial success. Sometimes thinner than a millimeter, they’re used in cards, tags and medical monitoring devices. According to the report, little is known about the environmental impact of printed batteries.
But the major drawback that halts mass commercialization of electric cars is its price. Largely because of what goes in them. An EV uses the same rechargeable lithium-ion batteries that are in your laptop or mobile phone, they’re just much bigger to enable them to deliver far more energy. The priciest component in each cell is the cathode, one of the two electrodes that store and release a charge. That’s because the materials needed in cathodes to pack in more energy are often expensive. Costs aren’t expected to keep falling as quickly, but lithium-ion packs are on track to drop to $93 per kWh by 2024, according to BNEF forecasts. To get there, one focus for manufacturers is replacing high-cost cobalt with nickel. That has a double benefit: nickel is cheaper and it also holds more energy, allowing manufacturers to reduce the volume needed.
On the other hand, cobalt’s advantage is that it doesn’t overheat or catch fire easily, meaning manufacturers need to make safety adjustments when they use a substitute. Panasonic Corp. in Japan plans to commercialize a cobalt-free version of a high-energy battery in two to three years; other suppliers already produce lower energy ones.
Still in more economically endowed countries like Norway electrical cars have settled their position as the favorite. About 70 percent of cars bought there in 2020 are EV. For these countries, the numbers are rising from scanty to substantial. Perhaps when we develop cheaper EVs, it would be commercialized for an average economy.
Conclusion:
As EV’s become more common and manufacturing becomes more widespread, battery recycling will be more efficient and reduce the need to extract new materials, therefore lessening the reliance on mining and production of new batteries. The total impact of electric vehicles is more pronounced when looking at their complete lifetime, where combustion engine vehicles are unable to compete. EV’s are responsible for considerably lower emissions over their lifetime than vehicles running on fossil fuels, regardless of the source that generates that electricity. Electric vehicles as they currently stand are far less polluting than their combustion engine counterparts. As the technology becomes more mainstream, it is likely to become even more efficient and sustainable. Economies of scale will benefit EV manufacturing by providing better infrastructure, more efficient manufacturing techniques, recycling options and reducing the need for the mining of new materials.
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