A Comparison of the Environmental Consequences in the Production and Disposal Phases of Lithium-Ion Batteries and Gasoline

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2016
Photo by Claus Ableiter
Photo by Claus Ableiter

Audrey Wen, Min-seung Kang, James Truncer

Abstract

Gasoline is recognized as an unsustainable energy source, and multiple industries now use lithium-ion battery alternatives to meet society’s demands for a shift away from nonrenewable sources. Lithium-ion battery powered products produce zero emissions and no toxic fumes, so they are deemed more eco-friendly than their gas counterparts. Yet, such a conclusion disregards the other environmental costs present in the earlier and later stages of the battery life cycle. The process of mining lithium and cobalt for lithium-ion batteries and the difficulties of recycling such materials should be taken into account just as the process of extracting gasoline from crude oil and the pollution from exhaust gases are. This study provides a comparison of lithium-ion batteries and gasoline as energy sources in the production and disposal phases from an environmental standpoint. Keywords: lithium-ion batteries, gasoline, life cycle analysis

Introduction

On October 9, 2019, the Nobel Prize in Chemistry was awarded to John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino for their work on the lithium-ion battery. The oil crisis of the 1970s, primarily consisting of the 1973 OPEC oil embargo and the 1979 Iranian Revolution, created an energy crisis in the United States, setting the stage for Whittingham to investigate fossil fuel-free energy technologies. He created a lithium battery with a cathode made from titanium disulphide and an anode made from metallic lithium. Later, Goodenough increased the power of the battery by using cobalt oxide in the cathode instead. In 1985, using Goodenough’s improved cathode and exchanging the metallic lithium in Whittingham’s anode with petroleum coke, Yoshino developed the first commercially viable lithium-ion battery (The Nobel Prize, 2019). Today, lithium-ion batteries power numerous portable, rechargeable electronic devices. They have set the foundation for the development of electric vehicles and renewable energy storage, marking them as a prominent energy source for this generation and the ones to come. Lithium-ion batteries accounted for 46% (U.S. Geological Survey, 2018) of the world lithium market in 2018, and quickly grew to 65% (U.S. Geological Survey, 2020b) in just two years. However, the growing demand in the market has fueled rapid production with priority on compact efficiency rather than environmental sustainability. Environmental consequences associated with lithium-ion battery production and disposal are beginning to catch up to the benefits that they have provided during usage.

Society has become heavily reliant on lithium-ion batteries (LIBs) to power our daily lives, but gasoline still remains a major source of energy. The biggest selling point for LIBs in the market comes from their eco-friendly disposition. Since LIBs run entirely on battery-electric power, they don’t directly tap into any nonrenewable natural resources. As a result, they are deemed zero-pollution, zero-emission wonders. Their rivals, items that run on gas, spit out their noxious fumes into the air we breathe through their exhaust pipes and continue to produce evaporative emissions during storage. Consequently, it is widely believed that LIBs do no harm to the environment; no visible emissions equal no damage. Contrary to popular belief, the LIB has a few environmental impacts under its name. The arguments for battery-electric over fossil fuels are largely founded upon emissions during the device’s usage period. A prominent flaw of this deduction lies in the lack of consideration for the materials and processes involved in the preceding and succeeding stages of the battery’s usage phase. Society overlooks the environmentally harming processes that mine the production materials in the cathode and anode of LIBs. Extraction and manufacturing processes degrade the local environment by exploiting natural resources and polluting human communities. While these batteries are rechargeable and usable for many years, there will be a point when consumers will repurchase items for an upgrade. In that case, disposal poses another issue since LIB recycling is an underdeveloped practice that is cost ineffective and environmentally unsustainable (Jacoby, 2019). Barriers to recycling lead to the growing electronic waste stream that increases opportunities for the hazardous levels of cobalt, copper, and nickel in the LIBs to seep into the land.

Of course, it is also necessary to acknowledge the environmental impacts from the gasoline life cycle. To get gasoline, crude oil needs to be extracted from underground wells, transported through pipelines and tankers, and finally refined into petroleum. Accidents may occur along the way in the form of oil spills that contaminate terrestrial and aquatic ecosystems. BP’s Deepwater Horizon oil spill in 2010 was an accident that contaminated the Gulf of Mexico with 134 million gallons of oil, killing thousands of marine animals and ruining their habitats. Up to 20% of oceanic juvenile Kemp’s Ridley sea turtles, which are protected under the Endangered Species Act, died from oil exposure, and bottlenose dolphins experienced a 50% decline in population in the years following the spill (National Ocean Service, 2017). Besides the energy intensive processes to obtain gasoline and the risks of habitat contamination, the fuel continues to contribute to global warming by producing carbon dioxide gas and other air pollutants when burned. Vehicle exhaust emissions resulting from the incomplete combustion of fuel are carcinogenic. As the environmental impacts from gasoline usage are more commonly known and more thoroughly investigated, they will not be discussed in this paper.

Anthropogenic impacts play a large role in the degradation of the environment through the depletion of resources, habitat destruction, and pollution. At a time when the Earth’s carbon dioxide emissions are at its highest in history (Statista, 2020) and the extinction rate is up to a hundred times higher than the natural baseline rate (Ceballos et al., 2015), it is critical to determine what energy pathway and source is the most sustainable for modern society. If batteries truly present a significantly advantageous solution, more resources should be invested in its development to further minimize its environmental footprint and spread the technology to other industries. If they are not as environmentally conscious as initially thought, society needs to make adjustments in its assessment of the heavily relied upon energy storage unit.  

A comparative analysis of the production and disposal of LIBs and gasoline reveals the environmental consequences present in the processes of each of their starting and end life stages. While there are overlapping areas in the life cycles of LIBs and gasoline, existing data is not particularly comparable. Significant environmentally threatening activities will be discussed for each. 

LIB Production

Beginning in the production stage, environmental costs can be analyzed through the processes in which materials are derived from the natural world. Lithium and cobalt are the two most characteristically LIB minerals and will be further explored here.

Lithium is found in brine, sedimentary, and pegmatites deposits, with much of the global lithium supply coming from the former as it is closest to the surface (Andersson as cited in McManus, 2012). In hard rock, lithium is extracted using a wide range of hydrometallurgical processes that use aqueous solutions to recover metals from ores. While hydrometallurgy is more environmentally friendly than pyrometallurgy, water pollution and hazardous solid discharge are still issues of concern. Pegmatite extraction processes are complicated and costly, but this exploitation persists due to the wider geographical distribution of hard rock (Kelser et al. as cited in Flexer et al., 2018).

On the opposite end of the spectrum, up to 80% of the world’s lithium brines are concentrated in a small region known as the Lithium Triangle, a region covering sections of Argentina, Bolivia, and Chile. Brines are highly saline solutions with high concentrations of mineral salts. Lithium is extracted using an evaporitic technology in which the brine is pumped from saltars (salt lakes) into open air shallow evaporation ponds (Flexer et al., 2018). Through successive evaporation from the sun and wind, the brine is concentrated and goes through chemical treatment. After a period of 12 to 24 months, lithium carbonate is precipitated. Based on an energy assessment by Gaines and her team in 2010, 40.2 MJ of purchased energy is required to produce one kg of lithium carbonate (Gaines et al., 2010). The evaporitic technology is relatively low-impact as it is a low cost and high margin process. Saltar brines occur in high altitude low rainfall areas so solar and wind evaporation are effective in concentrating brines and precipitating salts (Flexer et al., 2018). Even so, evaporitic technology still brings the issues of water usage and waste generation to the scrutiny of environmentalists. 

Lithium mining through brines makes use of brine water, which is eventually evaporated, and fresh water, which is needed in the purification process. Brine water is found within the salar, while fresh water borders the salar in free aquifers. However, there is concern that the two hydrodynamic systems are interacting. Depending on the pumping rate and location of the wells, as well as the magnitude of the salars, the water systems will have varying degrees of interconnection. Porosity and permeability of the salars determine if fresh water will be able to enter from the outside. Fresh water entry into brine aquifers will dilute the resource, producing extracted brines of lower lithium content. Most importantly, fresh water permeating into brines is an unfortunate loss of the supply to mining exploitation. For every ton of final battery grade lithium carbonate that is produced, up to 50 cubic meters of fresh water is needed (Flexer et al., 2018). In the arid land, pumping such a huge volume takes away from the fresh water availability for local flora and fauna in the biodiversity hotspot encircled by the Lithium Triangle. Water is the main limiting ecological factor, and lithium mining is disturbing the hydric balance for the already endangered endemic species.

The second issue lies in the large volumes of waste leftover from brine evaporation. Since brines have a high concentration of dissolved solids, but only lithium carbonate is desired as the end product, waste is accumulated at the edge of the salar. Producing one ton of lithium carbonate through water evaporation results in 115,041 kg of waste, primarily sodium and potassium salts, but also calcium oxide, magnesium hydroxide, and calcium sulfate. This waste is non-toxic, but its current management will pose a definite need for future action (Flexer et al., 2018).

Banza et al., Figure 1, Relation between concentrations of cobalt and 8-hydroxydeoxyguanosine (8OHdG) in urine
Banza et al., Figure 1, Relation between concentrations of cobalt and 8-hydroxydeoxyguanosine (8OHdG) in urine
Note. Individual data from adult residents (left panel) and children (right panel). Data from residents in the control area in green open symbols, data from residents in the mining area in red filled symbols. Note logarithmic scale of x-axis and y-axis. Spearman correlation is nonsignificant among adults (rho=0.23; 95%CI -0.25–0.62) and highly significant among children (rho=0.78; 95%CI 0.46–0.92; p<0.001).

Cobalt is another essential component of LIBs. 70% of the world’s cobalt production comes from Kinshasa, the capital of the DR Congo, and 80% of China’s cobalt consumption goes into the LIB industry (U.S. Geological Survey, 2020a). Unfortunately, the mining process is heavily questioned. A field study conducted by Banza and his team in 2018 in the town of Kolwezi in the DR Congo assessed the effects of the local artisanal cobalt mine on the area’s environmental and human health. They determined that the mining site contaminated the environment through spillage of ore during transport, handpicking ore fragments, and ore stockpiling inside the house. Ore-contaminated dust accumulated everywhere and was continuously resuspended to the point that their living environments were characterized as a mining area with an absence of mining activities. The residents’ and mineworkers’ internal exposure to cobalt and other toxic trace elements was compared to that of residents from an area without current or past mining through a urine analysis. Geometric mean concentrations of cobalt, manganese, and uranium were higher among exposed residents than control residents at a ratio of 7.1, 2.4, and 1.7 respectively. The urinary cobalt in adults, children, and miners largely exceeded the 15 µg/L cobalt limit set by the American Conference of Governmental Industrial Hygienists for the workplace. Children exhibited particularly striking internal levels of the metals associated with the ore, even displaying exposure-related oxidative DNA damage that points to an increased risk of cancer due to possible occurrences of genetic changes (Banza et al., 2018). It is evident that the mining and processing of heterogenite in the region has led to severe environmental pollution. The prevailing artisanal extraction of cobalt in the DR Congo is an example of unregulated extraction of a metal commodity that can expose toxic hazards and degrade a local environment. The currently existing cobalt supply chain is not sustainable.

Lithium and cobalt are just two of the various materials used to make a LIB, so the environmental harms discussed regarding the two elements are far from a comprehensive overview of all the issues related to LIB production. In the cathode, transition metals such as nickel, manganese, and aluminum can be paired with lithium, and each of them inflict environmental damage upon extraction. In the anode, graphite is the most commonly used material and requires some purification and processing steps (Goldman et al., 2019). Other components of the LIB include the electrolyte and separator, which again have their own processes and associated environmental costs. In the end, there are still manufacturing costs for the entire battery arising from factory emissions.

Chapman, Figure 2, Parts of a lithium-ion battery
Chapman, Figure 2, Parts of a lithium-ion battery

Gasoline Production

Petroleum is a finite, nonrenewable resource – the rate at which humans use it exceeds the rate at which the earth can replace it. This itself already paints crude oil extraction in a very unsustainable light. Beyond this point, drilling an oil well requires obtaining an area of land to create wells. In doing so, vegetation must be cleared from the land, eliminating the area’s plant life and affecting local animal species. Deforestation drives climate change on a local and regional level as forests absorb carbon dioxide and regulate temperatures. Changes in temperature alter ecological niches, impacting species selection and inviting invasive species (Meng, 2017). The loud human activity from extraction processes interrupts avian species’ communication (The Wilderness Society, 2019), while seismic exploration for oil underneath the ocean floor disturbs marine animals (Meng, 2017). Migratory animals are greatly impacted as they must navigate through gas fields with power lines, fences, and roads that cut through the natural habitat and impede their journey. While such infrastructure will eventually be removed once the region is exhausted, the damage done on the landscape is often irreversible. When the vegetation is stripped from the environment, soil erosion increases as there is more disturbance on the ground surface. The fragmented habitat will not fully recover on its own as there is little precipitation in the arid climates of fossil fuel development areas to stimulate regrowth (The Wilderness Society, 2019). Another aspect that may be inconspicuous is the glare that is emitted from the oil sites from the flaring of natural gases. The light, which is almost as bright as industrialized cities, pollutes the environment and disrupts the cycles of pollinators, resulting in dwindling populations of plant species that rely on them for reproduction (The Wilderness Society, 2019).

Howarth et al., Figure 3, Fracking infrastructure

Hydraulic fracturing, or fracking, is commonly used to facilitate the production of oil. The technique pumps large volumes of high pressure fresh water, along with potentially hazardous chemicals and sand, into the well to fracture the shale formation and encourage the release of hydrocarbons stored within the rock. One fracking well needs anywhere from 2-20 million gallons of water for operation (Jackson et al. as cited in Meng, 2017). Thus, immense amounts of wastewater containing dissolved contaminants and enriched metals is left over for treatment and disposal. If the wastewater isn’t delivered to municipal sewage plants, it is often disposed of by injection into saltwater aquifer wells. Underground injection is responsible for inducing man made earthquakes (Schmidt, 2013). 

Petroleum hydrocarbon pollution in the environment is a major concern. Multiple opportunities arise in the drilling production operations in the upstream industry, transportation and storage in the midstream industry, and refining and distribution in the downstream industry for oil spills. On land, gravity pulls the spilled oil into the soil until it reaches bedrock, watertight clay, or an aquifer. As the crude oil is highly immiscible, free oil accumulates on the surface of groundwater and laterally travels out from the point of pollution to distant zones. The polluted groundwater is a media in which plants, animals, and humans are exposed to petroleum hydrocarbons (Onwurah et al., 2007). An experiment conducted by Kisic and his team in 2009 determined the effects of drilling fluids and crude oil on some chemical characteristics of soil and crops. Chemical properties of the clean soil were most impacted by drilling fluids, while plant density and yield were more affected by crude oil. Throughout the four year trial, soil pH, contents of organic matter, and heavy metals remained at the same levels (Kisic et al., 2009). Soil bioremediation partially solved the problems posed by total petroleum hydrocarbons and polycyclic aromatic hydrocarbons, but it was unable to address the heavy metals. One example of this negative impact is the decrease in food productivity in Nigerian farm lands due to the oil spills on the dry land in 1978 and 1979 (Onyefulu & Awobajo as cited in Onwurah et al., 2007). The soil’s exposure to crude oil created anaerobic conditions that accumulated aluminum and manganese ions. Such conditions affected the germination and growth of crops such as rice, maize, and yams. To this day, the oil spills remain the greatest cause of depletion of the vegetative cover and the mangrove ecosystem in the Niger Delta (Odu as cited in Onwurah et al., 2007).

Aquatic ecosystems face their own set of challenges. Spills from ruptured pipelines, tanker operation accidents, industrial discharges, and urban run-offs account for the majority of petroleum hydrocarbon pollution in marine environments (Baker as cited in Onwurah et al., 2007). When oil is spilled on the ocean surface, waves and wind can churn up water-in-oil emulsions known as chocolate mousse. Containing up to 90% water, the mousse is extremely stable, making it very difficult to separate oil from water. (Payne et al. as cited in Nicodem et al., 1997). Microbial degradation is impeded by the mousse’s high viscosity (Seymour & Geyer as cited in Nicodem et al., 1997), so oil remains incorporated in water for long periods of time, resulting in the depletion of dissolved oxygen, loss of biodiversity, and eutrophication (Onwurah et al., 2007). Fish can suffer from lymphocytosis, epidermal hyperplasia, and hemorrhagic septicemia (Beeby as cited in Onwurah et al., 2007); mammals can be affected as if taken an anticoagulant (Onwurah as cited in Onwurah et al., 2007); seabirds can die (Dunnet as cited in Onwurah et al., 2007). 

As oil remains trapped in the ocean, its toxicity is affected by solar irradiation. Surface films become less toxic due to the loss of polycyclic aromatic hydrocarbons, but the tradeoff comes in the increased toxicity of the water soluble fraction of oil (Nicodem et al., 1997). This is referred to as photo enhanced toxicity (Barron et al. as cited in Onwurah et al., 2007). In Prudhoe Bay, crude oil exposed to ultraviolet light was found to be one hundred times more toxic to shrimps and bivalve embryos than unexposed crude oil (Pelletier et al. as cited in Onwurah et al., 2007). Bioaccumulation of solar irradiated crude oil activated chemical residues in fish and aquatic invertebrates that proved toxic (Calfee et al. as cited in Onwurah et al., 2007). 

There are many possibilities for environmental damage in the production phase of gasoline, but the most definite one comes from the emissions of oil refineries. 1.5 to 8% of a refinery’s feed is used as fuel for operation (Van Straelen, 2010). Refining crude oil requires a variety of processes with the most critical ones being separation, conversion, treating, and blending. In 2010, these processes contributed to approximately 22,000 tons of hazardous air pollution consisting of sulphur dioxide, nitrogen oxide, carbon dioxide, carbon monoxide, methane, dioxins, hydrogen fluoride, chlorine, benzene, and more (EPA as cited in EarthJustice, n.d.). In a typical refinery, carbon dioxide emissions can range from 0.8 to 4.2 million tons per year (Van Straelen, 2010). After refinement, the gasoline must be transported on marine vessels, rail cars, or tank trucks to get to distribution sites or storage centers. All of these vehicles require fuel and produce exhaust that is released into the atmosphere. These transportation costs are also environmental impacts from the final part of the production phase.

LIB Disposal

By 2030, industry analysts predict that 2 million metric tons of used LIBs will be generated annually worldwide (Jacoby, 2019). Considering the world’s massive consumption of LIBs, and the fact that these batteries contain valuable, recoverable materials, LIB recycling should be a prominent, if not a developing, field. Yet, very little recycling goes on today despite the ever increasing production – less than 5% of lithium ion end of life batteries are recycled worldwide (Li-Cycle Corp as cited in Church & Wuennenberg, 2019).

Jiang et al., Table 1, Spent LIBs generation from 2013 to 2020 in China
Jiang et al., Table 1, Spent LIBs generation from 2013 to 2020 in China

China’s recent economic development has been characterized by its large manufacturing base. Alongside other products, LIB production has increased rapidly, making China the second largest producer and exporter for LIBs in the world. Production of LIBs rose from 1.2 to 4.8 billion from 2007 to 2013. Due to the huge sales, China is expected to become the world’s largest producer of spent LIBs. In 2013, 57.2 kilotons of LIBs were abandoned. With an expected rise in LIB abandonment rate at 14.2% per year, 272.5 kilotons of electronic waste (e-waste) will be produced by 2020 (Jiang et al., 2015). China’s situation points at a clear need for the emergence of post-first life pathways to recycle the spent LIBs, even warranting them to create their own separate treatment facilities. Based on 2013’s 57.2 kilotons, China would need a total of 17 treatment facilities on a nationwide scale to fully recycle and dispose of the abandoned output (Jiang et al., 2015). Nigeria serves as another example of a country with a swift entry into the LIB market, but with insufficient planning for post-life options. In 2001, when the Telecom sector was first liberalized, Nigeria had a total Tele-density of 0.4% with a total of 400,000 subscriptions in fixed and mobile lines. Shockingly, in 2013, the country’s total number of subscriptions for fixed and mobile lines was at 117 million with a Tele-density of 83%, identifying the country as one of the fastest growing Telecom markets in the world (Babatunde et al., 2014). Despite this phenomenal growth in mobile telecommunication uptake, it has resulted in large quantities of unaddressed e-waste in the country. This may seem like an unfortunate commonality in developing nations. However, even in developed nations, like those in the European Union and the U.S., LIB recycling rates are less than 5% (Jacoby, 2019). The recycling rates in Australia are even lower at only 2% (Naomi et al. as cited in Jacoby, 2019).

Church & Wuennenberg, Figure 4, Barriers to lithium and cobalt recycling along the supply chain
Church & Wuennenberg, Figure 4, Barriers to lithium and cobalt recycling along the supply chain

While disappointing, there are certainly legitimate reasons for the underdevelopment of the recycling industry. Multiple issues arise in just the primary supply chain. A lack of transparency in the origins of the minerals used in production influences stakeholders’ decisions on the secondary processes that the product can undergo. Many are hesitant to recycle or remanufacture the spent LIBs because cobalt sourcing is heavily connected with child labor and human rights abuses in the DR Congo. Raw material price fluctuations also cause uneasiness in the development of the recycling industry: increase in raw material prices may provide economic grounds for second-life opportunities, but they also suggest that cheaper and more stable substitutes need to replace the existing minerals, further distancing the considerations of recycling (Church and Wuennenberg, 2019). The different minerals composing battery chemistry introduce another variable into recycling. LIB cathodes are made with a wide diversity of materials, including but not limited to LCO, LiNiO2, LiMn2O4, LiFePO4, and Li(NiCo)-O2 (Kang et al., 2013). Furthermore, even within one type of cathode, the proportions of components can vary significantly among manufacturers (Jacoby, 2019). Proper sorting and identification of the battery’s chemistry presents a major blockade in recovering lithium batteries. If sorting the existing waste isn’t hard enough, the chemistry and technology of lithium batteries are still evolving as new models are being introduced (Contestabile et al., 1999). With the assortment of possible battery compositions, not only does recycling require an extended and complicated sorting process to ensure the batteries meet the specifications of recyclers, there isn’t a single and straightforward process that can recover the minerals from any given LIB. An efficient recycling process is hard to develop without knowing the composition of the batteries subjected to the treatment. Perhaps most significant to the lack in LIB recycling is the absence of second-life anticipation in current product designs that limit possibilities for lithium and cobalt recovery due to their permanent assembly methods and compact structures. This single use mindset stretches to consumer expectations, resulting in the retention of products that are no longer used and keeping them from entering possible second-life pathways (Church and Wuennenberg, 2019). A survey conducted by Wilson and his team in 2017 in the UK on 181 participants found that only 33.7% of mobile phones reentered the system, whether it be left at a recycling center or store, donated, sold, or gifted – a phone that reentered the system did not guarantee that it was reused or remanufactured. 56.97% of phones were found to be kept for an average of three years, longer than their less than two year usage period, primarily to function as a spare. It was approximated that 3.85 million phones were kept in storage by UK higher education students alone (Wilson et al., 2017). The total number of hibernating phones held by the entire UK population, let alone the entire European or world population, would be beyond imaginable in enormity and consequentiality. By keeping the phones in hibernation, the supply of valuable minerals available for recycling is limited, thus decreasing recycling rates and downplaying the necessity for the recycling industry.

Kang et al., Figure 5, Measured levels of six metals in disposed LIBs vs. their regulatory thresholds
Kang et al., Figure 5, Measured levels of six metals in disposed LIBs vs. their regulatory thresholds

Due to such barriers in lithium and cobalt recycling, lithium batteries end up contributing to e-waste, the fastest growing segment of the U.S. solid waste stream (Ogunseitan et al. as cited in Kang et al., 2013). Research on potential environmental and human health impacts of LIBs in e-waste by Kang and his team in 2013 evaluated metallic content of LIBs by taking a look at sixteen cell phone batteries. Aluminium, cobalt, copper, and lithium accounted for 97.32% of the total metals. It was determined that all the LIBs tested exceeded the California regulatory thresholds for cobalt and copper. The limit of cobalt is 8000 mg/kg whereas the average concentration found in the batteries was 123213 mg/kg. The limit of copper is 2500 mg/kg whereas the average concentration found in the batteries was 103693 mg/kg. 75% of the LIBs exceeded the California regulatory threshold for nickel. The limit of nickel is 2000 mg/kg whereas the average concentration found in the batteries was 13430 mg/kg. Additionally, some LIBs had excessive levels of lead that exceeded the limit of 5 mg/L. Cobalt, copper, and nickel were found to have the highest total resource depletion potential, human toxicity potential, and ecotoxicity potential based on a life cycle impact assessment (Kang et al., 2013). The results demonstrate that LIBs are hazardous under U.S. state laws. Under the simulated landfill conditions carried out by Kang and his team’s study, cobalt, copper, nickel, and lead will leach out concentrations exceeding regulatory limits, harming surrounding ecosystems and affecting human health. Human intervention in biogeochemical cycles, in this case the disposal of e-waste, causes adverse effects in the natural environment. LIBs are agents of environmental pollution, especially in areas without proper solid waste collection and recycling.

When LIBs aren’t recycled, on top of being potential sources of metal pollutants, they also encourage additional mining for new minerals in production. Lithium recycling rates have historically been insignificant (U.S. Geological Survey, 2018), forcing continuous mining to meet consumer demands. Forecasts suggest that lithium recycling rates will remain low as the recycling infrastructure remains insufficient (Gardiner as cited in Church & Wuennenberg, 2019). Cobalt recycling rates, at 32%, are considerably higher than those of lithium (OECD as cited in Church & Wuennenberg, 2019). Scrap cobalt accounted for 29% of the overall U.S. supply in 2019, but still falls short of economic capabilities and requirements to meet predicted supply shortfalls (U.S. Geological Survey, 2020a). In the long run, battery production may decrease global cobalt reserves by more than 10% (Jacoby, 2019). As not enough minerals are being returned back to the system, more has to be taken from the earth, increasing the already severe environmental implications in the production phase of LIBs. This linear system encourages avoidable behavior at the start of the cycle.

Gasoline Disposal

Gasoline is consumed entirely during the usage phase of any device or vehicle. There is nothing to dispose of or any second life opportunities. If disposal is defined as any hazardous waste entry into the environment, petroleum hydrocarbon pollution has been addressed in the production phase.   

Conclusion

No conclusive statement can be made regarding whether LIBs or gasoline outcompetes the other from an environmental standpoint. Their impacts fall on varying ecosystems and even areas that overlap don’t have corresponding data. The one certain fact is that both energy sources provide tremendous assistance in our modern lives, but are also responsible for environmental harm that we are either unaware of or choose to sweep under the rug.

LIB production is composed of mineral extraction and battery manufacturing. Lithium extraction relies on pyrometallurgy in hard rock and evaporitic technology in brines. Both approaches pollute fresh water and produce solid waste, while also rendering the environment unable to recover from exploitation. Cobalt extraction has been found to expose toxic hazards to the surrounding environment and harm human health.

Gasoline production clears vegetation from an area of land for the creation of well pads. Before the drilling process begins, damage on the ecosystem is already irreversible as biodiversity diminishes and ecological niches change as a result of deforestation. Fracking requires large volumes of fresh water and turns it all into waste water that must be treated or disposed of. Oil spills along the production process pollute groundwater and affect plant growth on land. In the ocean, oil toxicity increases and affects all life in its waters. Finally, oil refineries emit tens of thousands of tons of air pollution consisting of toxic oxides and carcinogens. 

LIB disposal is supplying the increasing stream of e-waste. The insufficient recycling processes lead to disposal in landfills in which there are risks of environmental pollution. Based on this analysis, the most obvious first step to take in improving the sustainability of the LIB industry is developing the recycling sector. This is a straightforward solution to the disposal of hazardous LIB waste that would reduce harmful outcomes in the environment and increase the supply of reusable material to prevent the continuous mining of raw materials for production. A circular energy system is necessary to make the most use of nature’s resources before inflicting extra damage on the environment. If the disposal phase is made more environmentally conscious, the entire LIB industry will become more sustainable. This is simple in theory, but in reality it will be difficult to create an efficient recyclable sector due to the variations in LIB compositions. An equally difficult way to combat this issue would be to regulate all LIB compositions by standardizing their materials and structures.

Evidently, a comparison between the sustainability of LIBs and gasoline is challenging due to their different forms, life phases, and usage circumstances. There are multiple studies that provide a life cycle analysis of LIBs and the effects of extracting minerals, such as lithium and cobalt, on ecosystems. Likewise, the petroleum industry and drilling consequences have been extensively covered. Nevertheless, a scientific comparison presenting quantitative data spanning the entire life cycles of the two critical energy sources does not exist. To provide a proper analysis and evaluate the sustainability of LIBs and gasoline, a precise statement of units of energy produced for societal usage per units of energy expended for production should be calculated. Additionally, the toxic equivalency potential, human toxicity potential, terrestrial ecotoxicity potential, and marine aquatic ecotoxicity potential should be calculated in a life cycle analysis to determine environmental ramifications. The most crucial integrant in such a life cycle analysis would be to present LIBs and gasoline in an easily comparable manner that provides a confident answer as to which can provide the greatest gains with the fewest losses. To achieve the most accurate results, everything should be broken apart into categories more specific than production, usage, and disposal. In this way, future efforts to improve upon the two energy pathways will have an idea as to which areas should be addressed in order to achieve the maximal benefits.

This paper mentions several ways that environmental degradation can occur through hazardous waste pollution. Yet, they are all just possibilities, and the extent to which they occur and affect the environment is not known with certainty. The likelihood for LIB components to enter the ecosystem by being thrown into a landfill and the degree of photo enhanced toxicity of oil in oceans should be analyzed for a better interpretation of their environmental implications. Overall, further research should be done to assess the life cycles of LIBs and gasoline.