The Environmental Impacts of Li-ion Batteries
- Owen Li
This was written for my work-term report, the sources may be of interest.
Areas of interest:
Extraction of Raw Materials
Manufacturing
Lifetime, durability, longevity
End of Life and disposal
A carbon footprint comparison between Li-ion batteries and fossil fuels?
This will take longer to research
Lithium ion batteries are a type of rechargeable battery. They use an intercalated (a reversible inclusion or insertion of a molecule or ion into a layered material) lithium compound as the positive electrode and typically graphite at the negative electrode. Li-ion batteries have a high energy density, no memory effect (if nickel-cadmium batteries are repeatedly recharged after being only partially discharged, they seem to ‘remember’ a smaller capacity), and a low self-discharge.
https://batteryuniversity.com/article/bu-1001-batteries-in-industries (None of this is relevant to the title)
Lithium ion batteries are low maintenance, they can be left at any state-of-charge without adverse side effects.
While a modern Li-ion battery delivers about 150 Wh/kg of energy, the net calorific value (NCV) of fossil fuels is over 12,000 Wh/kg. So even though the ICE is only 25% efficient, the energy from batteries is still a fraction compared to fossil fuels. Not to mention ICE can operate in extreme cold and heat, which is difficult for batteries.
What is stopping Li-ion from being used as the battery on planes (not electric planes, but a battery similar to ‘starter’ batteries in cars) is the fact that Li-ion may have unexpected failures mid-flight. These can happen because of temperature fluctuations, ect. NiCd batteries are more durable and reliable, although they require high maintenance. However, NiCd is only used in specialty applications as it is terrible for the environment when discarded.
Li-ion is commonly used in satellites as they are light-weight, easy to charge, durable, have low self-discharge, and low maintenance.
Environmental impacts of lithium-ion batteries
Lithium-ion batteries contain less toxic metals than other batteries that contain lead or cadmium, they are therefor generally considered non-hazardous waste. They are safe for landfills and incinerators.
While safe in disposal, the physical mining of lithium and production of lithium-ion are both incredibly labor intensive, with most lithium-ion cells not being recycled, and incredibly costly on the environment.
With a greater demand for lithium-ion batteries, there is an increased strain on precious metals needed to produce li-ion, which create waste of their own.
There are ways to recycle li-ion batteries, but they are all more expensive than mining the ores themselves. As well, when manufacturing batteries, ease of recycling is not considered a design priority.
The spiralling environmental cost of our lithium battery addiction
In 2016 a toxic chemical leak from the Ganzizhou Rongda Lithium Mine in Tibet caused masses of dead fish to rise to the surface of streams, and many accounts of cow carcasses floating downstream from drinking contaminated water. It was the third time an incident like this occurred in the area in seven years as mining activity increased.
In South America, the main problem with Lithium mining is water. Argentina, Bolivia, and Chile contain over 50% of the world’s supply of Lithium. But it is also one of the driest places on earth. The issue with this predicament is that Lithium extraction is extremely water intensive, as the processes involves pumping water to create mineral-rich brine which is left to evaporate for months at a time. This is a relatively cheap and effective process, but it uses a lot of water - approximately 500,000 gallons per tonne of lithium. In Chile’s Salar de Atacama, mining activities consumed 65 per cent of the region’s water. Having a huge impact on local farmers who grow quinoa and herd llamas. And similarly to Tibet, there is potential for toxic chemicals to leak from the evaporation pools into the water supply. In Australia and North America, lithium is mined from rock using more traditional methods but they still require the use of chemicals to extract into a useful for of Lithium. In Nevada, studies found impacts on fish as far as 150 miles downstream. Not to mention the aftermath of mining companies leaves a radically changed landscape with mountains of discarded salt and canals filled with contaminated water with an unnatural blue hue.
Apart from Lithium, cobalt is another metal used in NMC batteries that has negative environmental impacts during extraction. Cobalt is found in huge quantities across the Democratic Republic of Congo and hardly anywhere else. One of the biggest challenges with this situation is that it is so abundant in the DRC that you can just dig up land and find cobalt, resulting in a lot of motivation for unsafe and unethical practices, including extracting materials by hand, without protective equipment, often using child labor, and definitely a lack of consideration of the local environment.
Research in Australia found that only 2% of the country’s 3,300 tonnes of lithium-ion waste was recycled.
https://www.nature.com/articles/d41586-021-01735-z
Lithium-ion rechargeable batteries — already widely used in laptops and smartphones — will be the beating heart of electric vehicles and much else. They are also needed to help power the world’s electric grids, because renewable sources, such as solar and wind energy, still cannot provide energy 24 hours a day. The market for lithium-ion batteries is projected by the industry to grow from US$30 billion in 2017 to $100 billion in 2025.
Batteries are often built into the devices they power, making them difficult to remove and recycle. Many batteries are also taken out of use and discarded prematurely because they are inefficient for a particular use, but they could still have plenty of life for less-intensive applications.
https://batteryuniversity.com/article/bu-901-fundamentals-in-battery-testing
Most medical and military devices are considered critical, so batteries are often replaced too soon so as to ensure no failures occur. However, medical technicians have discovered that many batteries for defibrillators have more than 90 percent capacity left when the mandatory 2-year replacement date passes. These batteries could easily be reused.
The manufacturing of electrodes uses N-Methypyrrolidone (NMP) to create a slurry that is coated on a current collector foil. It is then dried up to remove the NMP which is an indirect material (used for production but not in the final device). However, NMP ehibits flammable vapors and is highly toxic, needing to be recaptured, distilled, and recycled. There are current attempts to replace NMP with water, however the difficulty comes with water being a polar substance.
https://www.nrel.gov/docs/legosti/old/7673.pdf
BU-103: Global Battery Markets
37% of all battery revenue comes from Lithium-ion batteries. They are the battery of choice for portable devices and the electric powertrain in EVs.
BU-808: How to Prolong Lithium-based Batteries
Battery research is focusing on lithium chemistries so much that one could imagine that the battery future lies solely in lithium.
All battery systems have unique needs in terms of charging speed, depth of charge, loading, temperature, etc. In most consumer products li-ion life span is about 300 - 500 discharge/charge cycles. However counting cycles is not conclusive because a discharge may vary in depth and there are no defined standards of what constitutes a cycle.
After passing the above life span the batteries will not be unusable just be below a certain percentage of the original capacity (ex. 80% of original capacity)
Lithium-ion Battery Market Size, Share, Industry Trends and Growth Analysis 2033
The global lithium-ion battery market size is projected to grow from USD 41.1 billion in 2021 to USD 116.6 billion by 2030. Market growth is driven by surging requirements for continuous power supply for critical infrastructures, increasing demand for plug-in vehicles, growing need for battery-operated material-handling equipment in industries due to automation, continued development of smart devices, and lithium-ion battery storage for renewable energies.
NMC batteries are used for mobile phones and electronics, battery storage stations, and electric vehicles.
https://www.nytimes.com/2021/05/06/business/lithium-mining-race.html
Proposal of Lithium mine states that billions of gallons of ground water will be used, with some of it being unsafe for drinking for 300 years. And toxic waste containing large amounts of sulfuric acid and possibly modestly radioactive uranium will be left behind.
Manufacturing a battery pack alone would generate 74% more emissions than the entire conventional car.
https://sgp.fas.org/crs/misc/R46420.pdf
In addition to a review of the literature, CRS focused on the results of one study in order to present an internally consistent example of an LCA. This specific study finds that the life cycle of selected lithium-ion BEVs emits, on average, an estimated 33% less GHGs, 61% less volatile organic compounds, 93% less carbon monoxide, 28% less nitrogen oxides, and 32% less black carbon than the life cycle of ICEVs in the United States. However, the life cycle of the selected lithium-ion BEVs emits, on average, an estimated 15% more fine particulate matter and 273% more sulfur oxides, largely due to battery production and the electricity generation source used to charge the vehicle batteries. Further, the life cycle of the selected lithium-ion BEVs consumes, on average, an estimated 29% less total energy resources and 37% less fossil fuel resources, but 56% more water resources. These results are global effects, based on the system boundaries and input assumptions of the study.
How Long Do Electric Car Batteries Last? | Geotab