Introduction

The invention and commercial adoption of the lithium-ion battery (LIB) has enabled a plethora of new technologies, making our world more mobile than ever. This mobility extends beyond consumer electronics such as smartphones, laptops, smartwatches, and tablets, to electric vehicles (EVs), which have been designated as a critical tool in the current fight for environmental sustainability. LIB use in EVs is regarded as one of the most effective and attainable solutions to climate change, promising to cut down on the 29% of CO2 emissions attributed to transportation in the United States.1 Indeed, this technology holds a beacon of hope. Over an 180,000 mile (~290,000 km) lifetime, a US-based midsize battery electric vehicle will reduce emissions by 42% compared to a similarly sized internal-combustion-engine vehicle (ICEV).2

The adoption of EVs will also provide lesser-mentioned benefits that could improve human health. Recently released EVs, for example, have even begun incorporating vehicle-to-grid and vehicle-to-home charging, expanding the horizon of their application as mobile generators. The Ford F150 electric pickup truck, for example, can power a single-family home for up to 10 days during a power outage, a potentially lifesaving capability in the case of extreme weather.3 EVs are also projected to improve air quality by limiting particulate emissions. In Norway, the widespread adoption of EVs has contributed to a 75% drop in harmful particulate matter (PM2.5) emissions.4 In the US, adoption of EVs is projected to prevent 150,000 premature deaths by 2050 due to air quality related conditions such as asthma, cancer, cardiovascular disease, and more.4 With so many promising applications and benefits, it is no surprise that the demand for this technology is increasing. The electric car market, majorly dominated by China, Europe, and the United States, has exponentially grown over the last few years. In 2022, 14% of all new cars sold worldwide were electric, which accounts for one in every seven cars sold, whereas in 2020, less than 5% of all cars sold were electric.5 In 2023, a 35% year-on-year increase in EV sales was expected all around the world.5 As LIBs are one of the most crucial components for EVs, the rising demand for EVs not only escalates the need for better battery materials, but also intensifies the environmental impact of their mining and strains the supply chain.

LIBs used in today’s electric vehicles come in a variety of chemistries, each with its own distinct working mechanism. Despite the decades of research that has optimized the components in commercial LIBs, the pursuit of greater energy density, enhanced cycle life, and improved safety continues to demand concerted efforts from both the industrial and academic communities. In this article, we aim to provide an overview of the current state-of-the-art battery materials—different materials chemistries employed in LIBs for EVs, their current market status, and their environmental impact. We will discuss the most promising materials design strategies to develop the next-generation batteries for EVs with enhanced performance. Specifically, we will discuss the cathode materials in depth, as they are the major determinant of energy density and battery cost, while also introducing the anode and electrolyte materials. Finally, we offer our insights on the future of EV battery chemistries, based on the current trends in industrial and academic research.

From charge to motion: Working mechanism behind LIBs in EVs

At the core of the battery unit of a typical electric vehicle is a battery pack, which is composed of several battery modules. These battery modules, in turn, are made up of individual battery cells, as shown in Figure 1a. The core components of a battery cell are the positive electrode (cathode), negative electrode (anode), electrolyte, and a separator that prevents physical contact between the electrodes. These battery cells function based on the shuttling of Li+ ions between a positive and negative electrode through an organic liquid electrolyte under an applied electric field. At the same time, electrons move in the same direction through an external circuit to maintain the charge neutrality of the system. During charging, the Li+ ions move from the cathode, which is typically a transition-metal-based oxide or phosphate, to the anode, which is carbon-based. The opposite process occurs during discharge, as illustrated in Figure 1b. This process is repeated over thousands of cycles during the lifetime of a battery.

Figure 1
figure 1

(a) Schematic representations of EV battery components at multiple length scales: at the largest scale, a battery pack is comprised of  several battery modules integrated with control units, such as a battery management system (BMS). These modules consist of a specific number of battery cells, encased in a frame for protection. Each cell contains major components such as the anode, cathode, electrolyte, and separator. The cathode is constructed from microscopic active material particles combined with a conductive additive and a binder. At the atomic scale, the cathode’s crystal structure features a stacked arrangement of transition-metal oxide layers, with Li+ ions intercalated between them. (b) Working mechanism of a typical LIB during discharge: the Li+ ions move from the anode through the electrolyte toward the cathode where they are intercalated inside the cathode’s crystal structure; the electrons move in the same direction through the external circuit at the same time, powering the vehicle.

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During the initial charge/discharge cycles, a passivating interphase is formed on the electrodes as they react with the electrolyte, known as the cathode electrolyte interphase (CEI) on the cathode side, and solid electrolyte interphase (SEI) on the anode side. These interphases should facilitate efficient movement of Li+ ions, exhibiting minimal interfacial resistance under varying temperatures and current densities. They should also be insulating to electrons to inhibit further reactions with the electrolyte and have superior chemical and mechanical stability. Over the LIB’s lifetime in an EV, a robust electrode/electrolyte interphase is crucial to ensure high Coulombic efficiency, prolonged cycle life, and safety.

Major cathode chemistries in LIBs for EV and market dynamics

For effective use in electric vehicle batteries, a superior cathode needs energy density that can extend the range of EVs, prolonged cycle life for battery longevity, as well as improved thermal stability to reduce fire hazards. To meet these requirements, commercial EV batteries typically utilize intercalation chemistry, where Li+ ions are inserted into and removed from a host structure during cycling. High-quality intercalation cathode materials are characterized by their ability to efficiently accommodate reversible intercalation of Li+ ions, while preserving the integrity of the host crystal structure. Figure 2 shows the crystal structures of popular cathode materials for EV batteries, their projected market shares, and energy densities. Some of the most dominant cathode materials for EVs are LiFePO4 (LFP), LiMnxFe1−xPO4 (LMFP), LiNixCoyAlzO2 (NCA), LiNixMnyCozO2 (NMC), and LiNixMnyCozAl1−x−y−zO2 (NMCA). NMC, NCA, and NMCA possess a layered crystal structure, whereas LFP and LMFP have an orthorhombic lattice structure belonging to the olivine family. The structure of both materials can be seen in Figure 2a. The selection of cathode materials hinges on the desired battery performance parameters such as energy density, power density, and safety, with cost also being a crucial consideration for commercial applications. Figure 2b depicts the range of specific energy (Wh kg−1) and energy density (Wh L−1) of these chemistries.

Figure 2
figure 2

(a) Crystal structure of olivine-structured and layered cathodes. The blue color in the layered structure represents transition metals, which are usually Ni, Mn, and Co. (b) Energy density versus specific energy of LFP and layered oxide cathodes in cylindrical, pouch, and prismatic cell configuration adapted with permission from Reference 6. The data in this graph are for single-cell level and may not always translate equivalently to system-level performance. (c) Market share projection of different EV cathodes (adapted from reports of S&P Global Market Intelligence).7 The projections illustrated here could change in response to the emergence of new regulations and the introduction of more advanced technologies in the market.

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Many western carmakers in Europe and the United States prefer batteries with the NMC cathodes, which power the BMW i3 and Chevy Volt. The energy density of NMC cathodes increases with higher Ni content, which translates into longer range for the EV. Key EV manufacturers such as Tesla have opted for another high Ni containing layered cathode NCA, likely due to its higher thermal stability.8 Since their extended collaboration with battery manufacturer Panasonic from 2013, they have been predominantly using NCA in their best-selling cars such as the Model S, Model X, and Model 3. Another variant of this chemistry, NMCA is used by General Motors in their Ultium batteries. These compositions also reduce the use of cobalt, potentially alleviating the geopolitical and distribution issues related to cobalt mining, which we elaborate on in the next section.

In contrast to layered NMC materials, LFP cathodes possess lower energy density but excel in long-term cycling stability and maintain consistent operational voltage, reducing stress on EV power electronics and battery management systems.9 Moreover, these cathodes provide higher thermal stability and longer lifetime.10 Market share of LFP increased from 17% in January 2021 to 26% in January 2022 and accelerated to 31% in September 2022.11 Although this material was first discovered by John B. Goodenough in the United States, until now the major market has been in China where short-range EVs are very popular. Now western carmakers are also moving toward adopting LFP chemistry, due to the growing issues with critical mineral supply chain. Tesla has played a pivotal role in changing this market dynamics by announcing their shift to the LFP chemistry in October 2021. Since then, many carmakers such as Ford, Rivian, Volkswagen, and GM have announced their imminent adoption of LFP or LFMP chemistry. The rising market demand of this chemistry is creating increasing opportunities to establish LFP and LFMP manufacturing in the United States. In this regard, innovations in manufacturing technologies are necessary to comply with stringent environmental regulations and to utilize alternative precursor materials. This could potentially lead to reduced costs and more environmentally friendly manufacturing processes.

Regardless of the choice of battery chemistry, battery manufacturers worldwide are constantly trying to increase their production capacity to meet the global demand, which is projected to be 4500 GWh by 2030.12 Companies such as CATL, Northvolt, LG Chem, and SK Innovations plan to meet the rising demand by expanding their production capacities in gigafactories, which will scale up battery production significantly. This is reflected in the significant price reduction of EV battery packs in 2023 ($139/kWh on a volume-weighted average basis) after their unprecedented price increase in 2022.13 Government initiatives are also positively influencing the market through their supportive policies. For example, the 2022 Inflation Reduction Act and the 2021 Infrastructure Investment and Jobs Act are expected to significantly boost domestic production of batteries and sales of EVs in the United States.

Materials-level challenges and design strategies

From a materials standpoint, numerous challenges are associated with the anode, cathode, electrolyte, and the electrode/electrolyte interface in an LIB, which impedes the advancement of next-generation batteries for EVs. Herein, we discuss the complex challenges associated with the different components of an LIB, and the materials design approaches taken to overcome them (Figure 3).

Figure 3
figure 3

Some of the latest developments in materials design strategies for (a) cathode: synthesis control approaches such as design of concentration particles, elemental doping, modification of particle morphology and grain orientation to increase energy density and mitigate degradation; (b) electrolyte: use of fluorinated electrolytes, weakly solvating localized high concentration electrolytes and electrolyte additives to enable high-voltage application and fast charging of EV batteries; and (c) anode: schematic illustrations of Si or Si/C composite anodes, surface modification of graphite anodes, and anode-free lithium-metal batteries to enable the next-generation high-energy lithium-based batteries for EVs. CEI, cathode electrolyte interphase, SEI, solid electrolyte interphase.

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Materials-level challenges in LIB cathode

On the cathode side, despite the commercial success of LFP in mid-range electric vehicles, this material is hindered by its poor ionic and electronic conductivity. The one-dimensional Li+ ion diffusion channels in LFP are often obstructed by antisite defects, a condition where iron atoms occupy lithium sites within the crystal structure.14,15 This issue significantly impairs the electrochemical performance of the cathode material. While strategies such as nanocrystallization and carbon coating have been employed to address conductivity problems,16 these measures do not overcome the material’s inherent limitation in energy density, as it maintains an average operating voltage at 3.4 V versus Li/Li+. Another emerging class of cathode is LiFexMn1−xPO4 (LFMP) that integrates Mn in the LFP framework.17 Inclusion of Mn can widen the ion diffusion channels through introduction of lattice defects and elevate the discharge voltage platform through the Mn2+/Mn3+ redox couple. Current research explores various strategies, including electrolyte modification, elemental doping, morphology engineering, and surface coating to address Mn dissolution issues in LFMP materials, thereby improving their rate capability, energy density, and thermal stability.16,18,19,20,21,22

In the case of Ni containing layered oxide materials, NMC and NCA cathodes offer higher capacity and rate capability, along with compositional flexibility. However, at the end of charge, highly reactive Ni4+ is formed in these materials, which triggers undesired side reactions with the electrolyte and cathode surface reconstruction.23,24 This also leads to dissolution of active materials and gas evolution,25 eventually causing capacity fading. Moreover, at high states of charge, these materials undergo phase transitions, accompanied by repeated volumetric changes of the lattice. This can induce mechanical stress in the material during each cycle, leading to their chemomechanical degradation in the form of intergranular and intragranular crack formation in the particles.26,27,28 Furthermore, high Ni layered oxides are prone to cation mixing—where Ni2+ ions occupy Li+ sites—leading to inactive phase formation that further reduces the capacity.29

The research developments in these materials have mostly evolved around improving the cycle life and capacity retention, while maintaining high energy density. The most common approaches include coating to reduce surface reactivity30,31,32,33,34,35,36 and doping to improve structural and thermal stability and reduce cation mixing.37,38 However, doping or coating can only delay the onset of degradation, and they also add inactive weight to the active material, lowering their energy density. Modifying the microstructure of the active materials through synthesis control can alleviate the degradation directly.39 Development of single-crystal materials,40,41 concentration gradient materials,42 and materials with controlled grain orientation43 can be highly effective in improving the chemical and mechanical stability of Ni-rich cathode materials for LIB. When designing cathode materials for practical applications, the effort should be directed toward the element minimization principle. Approaches involving the high-entropy design could substantially complicate the raw materials supply chain and are not practically appealing, even if all the claimed benefits of the high-entropy concept are true and the resulting materials are truly uniform at large scale.

To enhance the energy density and extend the cycle life of cathodes, it is also essential to gain a fundamental understanding of degradation pathways of cathode materials. Battery electrochemical reactions are highly heterogeneous in nature, which poses significant challenges in characterizing the resulting chemical and mechanical damage. Moreover, many degradation processes, such as surface reconstruction, parasitic reactions, and transition-metal dissolution, are complex and interlinked.44 State-of-the-art synchrotron x-ray-based characterization and electron microscopy techniques are crucial for the fundamental understanding of these mechanisms at a nanoscale, while advanced computational methods such as machine learning can offer deep insights into the complex behaviors of cathode materials and their degradation pathway.44,45,46,47

Electrolyte engineering and challenges at the interface

Electrolyte engineering plays one of the most critical roles in determining the stability and performance of a LIB. The electrolyte in an EV battery consists of a conducting lithium salt, typically LiPF6 dissolved in a mixture of carbonate-based solvents that usually contain ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC).

While the highly popular commercialized EC-based electrolytes can form a superior interphase on the graphite anode, their low anodic stability at high voltage (>4.3 V) hinders the commercialization of high-voltage cathodes, limiting the energy density of LIBs. Electrolyte engineering has been used to design more robust and stable interphases for high-voltage applications. A research drive toward developing EC-free electrolytes led to the development of other carbonate solvents with film-forming additives, for example, fluoroethylene carbonate (FEC) or vinylene carbonate (VC) additives in ethyl methyl carbonate (EMC) solvent, that can reinforce the electrode/electrolyte interface.48,49 Development of fluorinated solvents such as FEC and 3,3,3-trifluoropropylene carbonate (TFPC) provided better thermal stability with a LiF-rich interphase and were found to be good candidates for batteries operating at extreme temperatures and high voltages.50 More electrolyte candidates that are being explored to elevate the anodic stability at high voltages include sulfone and nitrile-based electrolytes, concentrated electrolytes, ionic liquid-based electrolytes, and electrolytes with multifunctional additives.48 Use of weakly solvating electrolytes can regulate the solvation structure of Li+ ions and promote interphases that mitigate the cointercalation of solvent molecules into the anode. For example, the design of weakly solvating electrolytes such as high concentration or localized high concentration electrolytes (LHCEs) create many contact pairs (CIPs) between the lithium cation and salt anion, whereas only a few CIPs exist in conventional electrolytes. This results in interphases with higher ionic conductivity, reduced polarization and improved thermal, mechanical, and chemical stability in both lithium-metal and lithium-ion batteries.51,52,53

The advancement of EVs depends on the fast-charging capabilities of the LIB. The US Department of Energy aims at achieving 80% charging in 15 min or less by 2028.54 Challenges to achieving fast charging stem from the polarization of the cell, which can lead to lithium plating on the anode as the potential drops to 0 V versus Li+/Li. Driven by the mass transport limitations and concentration gradients of Li+ ions in the electrolyte, irregular growth of metallic lithium occurs on the anode surface in the form of “dendrites.” This process is exacerbated by higher current densities and lower temperatures. These lithium dendrites further react with the electrolyte, causing irreversible electrolyte consumption and formation of “dead Li” that lose electrical contact with the anode, leading to the limited capacity and rapid capacity fading of the cell. To enable fast charging capabilities, low viscosity aliphatic esters and nitriles are used as co-solvents that can facilitate the rapid ion transport through the electrolyte, even at temperatures as low as –40°C.55,56,57 Additives of different lithium salts are often employed in the electrolyte to create a stable SEI that can promote fast charging. Some of these additives can homogenize the Li+ ion flux at the interface by increasing Li+ ionic conductivity, increase the inorganic components on the SEI and block the hotspot areas for dendrite nucleation.57 Moreover, recent developments in high-entropy electrolytes show that tuning solvation entropy through increasing molecular diversity of the electrolyte composition can improve transport properties and fast-charging capabilities in weakly solvating electrolytes.58,59

Development of fire extinguishing liquified gas electrolytes,60 fluorinated ether-based electrolytes,61 and multifunctional solvent molecules62 are some of the current research avenues to revive lithium-metal batteries for high-energy applications. Machine learning-based data-driven approaches are also emerging as a new tool to explore the vast composition space for electrolyte design.63

Design strategies of LIB anode materials

Graphite has prevailed as the anode material for application in LIBs for EVs due to its low redox potential, low cost, low toxicity, and high abundance. Although decades of research have significantly optimized many characteristics of graphite anodes, some challenges persist. These include the first-cycle irreversible capacity, lithium plating, and instability of the SEI. To overcome these issues, many approaches such as surface modification, carbon coating, incorporation of metals or metal oxides as composite or coating, use of polymer coatings have been undertaken.64 Nonetheless, the inherently low capacity of graphite anodes has prompted the current investigations into alternative materials with higher capacity, such as lithium metal or silicon anodes.

The alloying anode silicon is an abundant and environmentally friendly element with a theoretical capacity of 3578 mAh g−1, which has the potential to meet the high energy and high-power requirements for the next-generation LIBs. However, it comes with its own set of challenges of high volume change, high initial irreversibility, and poor mechanical stability of the SEI. Silicon—hard carbon anode materials are emerging as a solution to these issues, as hard carbon can act as a matrix to buffer the volume fluctuations of silicon. Hard carbon provides good conductivity, porosity and high surface area and can be derived from biomass waste, making it a sustainable choice for anode materials.65,66 Other strategies to improve the performance of silicon-based anodes include doping, design of nanostructured composites, and advanced binder materials.67,68,69,70,71 Anode-free lithium-metal batteries also have the potential to significantly increase the energy density by eliminating the anode active material in the as-made cell and utilizing maximum voltage output from the cathode.72

Battery supply chain challenges and environmental impact

To make progress toward carbon neutrality goals in alignment with climate policies, 500 million EVs are estimated to be used globally by 2050.2 Powering each of those vehicles will be batteries cumulatively containing greater than half a metric ton (mt) of aluminum, copper, lithium, cobalt, nickel, manganese, and iron.73 The surging demand raises supply chain security concerns. Specifically, experts worry that cobalt and lithium reserves will not meet this demand, with uncertainty stemming from demand projections that consider different rates of EV adoption and future cathode chemistries.

For lithium, the concern is not its scarcity, but the potential inability to extract it from the earth quickly enough to meet growing demand. According to the USGS, 26 million metric tons of global lithium reserves existed in 2022, a number that continues to grow substantially with resource exploration.74 However, extraction rates will need to grow significantly to meet demand, as lithium is a major component of not just the battery cathode material, but also the electrolyte salt. Annual lithium production has increased by roughly 60% between 2020 and 2022,74,75 but global EV sales have over tripled in that time  frame from 3.2 to 10.5 million.76 Such an imbalance of increasing supply and demand has caused projections of a lithium bottleneck, with some reports suggesting it is most likely to occur in 2025.77

For cobalt, supply chain concerns are based on the localized geography of extraction; in 2022, 68% of cobalt was extracted in the Democratic Republic of the Congo (DRC).74 Potential sociopolitical or economic instability in the DRC (or China, the world’s leading refiner of cobalt in 2022)74 could significantly diminish supply, sending cobalt prices soaring. In 2017, cobalt prices doubled due to supply deficiencies as EV demand increased.77 Additional supply chain concerns exist because cobalt is mostly extracted as a byproduct of other metals, particularly nickel and copper.74 In 2015, approximately 50% of cobalt was mined as a byproduct of nickel.78 This indicates that nickel supply chain disruptions could also produce cobalt shortages. Recently, great strides have been made toward improving and expanding battery recycling.79,80,81 In the future, a robust battery recycling system could alleviate future supply chain strain, producing full cobalt circularity as soon as 2040 if shifts toward low cobalt chemistries continue.82 Due to the long lifetime of EV batteries, however, recycled metals will not soon supply a significant portion of cobalt. Consequently, in studies forecasting the highest EV demand from aggressive policy adoptions, the cobalt supply chain is projected to bottleneck around 2035.77

Along with securing a sufficient quantity of metals, manufacturers should focus on creating a sustainable supply chain. While EVs produce fewer lifetime emissions than ICEVs, they emit approximately 70% more GHGs during manufacturing,2 mainly due to battery material mining, refining, and assembly. To maximize EVs’ lifetime emission cuts, manufacturers must secure resources and assemble cells in a way that limits GHG emissions. Lithium, for example, has two major supply chains; one is based on lithium extracted from the Atacama brine lakes in Chile, which is then also processed in Chile. The second is based on lithium mined from spodumene ores in Australia and refined in China. Compared to the Chilean brines, Australian lithium generates approximately two times more GHGs/mt LiOH produced and seven times more GHGs/mt Li2CO3 produced.83 While Australian lithium always produces more GHG emissions, the production route emissions difference for LiOH is smaller than Li2CO3 because LiOH is more directly produced from ore than from brine water. On a battery scale, the use of Australian lithium over Chilean lithium results in 20% and 10% higher GHG emissions for NMC622 and NMC811 cells, respectively.83 However, all salt brines are not equivalent. For example, Atacama brine lake in Chile produces just 3.4 kg CO2 equivalent/kg Li2CO3 compared to 31.6 kg CO2 equivalent/kg Li2CO3 produced from Chaerhan lake in China.84 This indicates that brine lake extraction is not always environmentally superior, but rather, that lake chemistry and energy sourcing heavily impact emissions.

A common theme recurring in these studies is that fossil fuels used by mining, refining, and manufacturing companies greatly increase the GHG emissions of their products. For instance, replacing Chinese lithium refiners’ current coal heating source with natural gas could reduce GHG emissions by 16% for LiOH and 23% for Li2CO3 production.83 Likewise, the high emissions associated with Li2CO3 production at Chaerhan salt lake were attributed to the fossil fuels used to supply its high-energy demand.84 In general, securing materials from suppliers less reliant on fossil fuels will significantly reduce GHGs from battery production.

Achieving a lower-carbon battery will involve decentralizing current supply lines from China, Indonesia, and other countries with carbon-intensive electricity mixes (see Figure 4). High-emitting Indonesia is currently the largest global supplier of nickel, while China dominates the materials refining, production, and cell assembly market. A 2024 study found that 92% of LFP and 80% of NMC cathodes contain elements that have passed through China during refining or production.86 This directly impacts the emissions associated with battery manufacturing. A 2023 analysis found that producing an NMC811 cell with processes (mineral mining, refining, and cell assembly) in lower carbon intensity countries (Canada, Norway, Brazil, USA, and Hungary) emits 57 kg CO2e/kWh. Conversely, producing the same cell in top-emitting countries (lithium mining, refining, and cell assembly in China and nickel mining and refining in Indonesia), emits 85 kgCO2e/kWh.85 Similarly, when analyzing the cobalt supply chain, Lima et al. found that utilizing a European-based supply chain significantly increased the likelihood of achieving UN sustainable development goals compared to the current global supply chain, even when both supply chains mined cobalt from the DRC.87 Once again, the primary reason for these emission reductions remains cleaner energy grids in lower-emitting countries, highlighting the necessity of co-adopting clean energy and electric vehicle production to maximize climate impacts. We expect that most countries will reduce emissions during battery manufacturing as the adoption of renewable energy increases in the coming years.

Figure 4
figure 4

(a) 2020 GHG emission ranges for each common battery material. Labels to the left and right of each range represent the lowest and highest emitting country that supplies that material or service, respectively.85 When the same country is the highest or lowest emitter for two separate processes related to the same material, the labeling is grouped. For example, the right side of the lithium hydroxide emissions range is labeled “M, R: China,” indicating that China produces the highest emissions of any country for mining lithium hydroxide and for refining it. Differences in emissions are related to national energy sources and method of material extraction or processing. Data are plotted from the Supplementary information of Reference 85. (b) Electricity emission factor values for countries identified as low and high emitters in Figure (a)85 in 2020. (c) Mining output of nickel, manganese, and cobalt as a function of country in 2020.75

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Perspective and future outlook

To summarize, we have explored various aspects of LIB chemistry for EVs, covering their fundamental working principle, key cathode chemistries, market dynamics, and material-level challenges in cathode, anode, and electrolyte design. We have also provided insights into the supply chain complexities and environmental impacts associated with the materials used in different LIB components. To meet the goals of carbon neutrality through a more sustainable materials chemistry approach, the advancement of better and alternate chemistries to the ones currently being employed for EVs must be constantly pushed. Localizing the battery mineral supply chain, minimizing or substituting critical minerals in battery components, adopting advanced technologies to lower emissions and water consumption throughout the mining and manufacturing stages, and implementing effective recycling and end-of-life management for spent batteries are all essential steps toward a greener future for EV batteries.

Among the technologies that are being sought after as an alternative to LIBs, sodium-ion batteries (SIBs) currently hold the most promise due to their high abundance and low cost of raw materials. SIBs can enable the incorporation of many abundant transition metals into a layered oxide structure, eliminating the need for the critical elements such as Li, Ni, and Co, and alleviating the strain on supply chain. Additionally, SIB adoption can lead to substantial cost advantages in manufacturing.88 Due to their inherently lower energy density than their LIB counterparts, they are more suited for lower range vehicles. Current efforts in this field are directed toward improving the cycling stability of cathode materials through composition tuning, doping, and coating, as well as developing advanced electrolyte and anode materials for improving fast-charging and low-temperature performance.89,90,91 Solid-state batteries also hold great promise in increasing energy density by enabling lithium-metal anode and ensuring better safety by eliminating flammable liquid electrolytes. Changing the liquid electrolyte with a solid inorganic or polymer electrolyte also opens opportunities to store more energy in a smaller volume, which could potentially increase the driving range of electric vehicles. Furthermore, the production cost of solid-state batteries can be significantly reduced by eliminating a series of manufacturing steps that are required for conventional batteries. It is important to note that more efforts are needed to drive these “solid-state promises” to reality. Furthermore, issues such as high reactivity at the interface, air instability, and poor mechanical properties of solid-state electrolytes have slowed down their industrial progress. Numerous approaches are being undertaken to enhance the adhesion, mechanical strength, and ionic conductivity of solid-state electrolytes, while also reducing interfacial resistance and suppressing dendrite formation. These include surface fluorination, development of multilayer and hybrid electrolytes, application of insulating coatings, doping or elemental substitutions, incorporation of silver-carbon interlayers, and the use of additives or active fillers.92 Another promising technology, Si and Si derivative anodes for high-energy batteries has already penetrated the EV market and are expanding through advanced technologies aimed at tackling their volume expansion challenge.93,94

Finally, we would like to conclude this article by emphasizing the importance of achieving better control over synthesis and manufacturing processes of battery materials. Most of the materials discussed in this article undergo several processing stages during manufacturing, each contributing to the cost and environmental footprint of the process. Therefore, manufacturing protocols should be chosen in a way that can optimize material stability and purity while reducing cost and energy requirements. Modifications to materials aimed at enhancing battery performance can potentially add to manufacturing costs. Therefore, research should focus on materials design that improves battery performance using simplified compositions, rather than adding complexity to the process. In addition to ensuring environmental sustainability and cost efficiency, each materials design and manufacturing process must be engineered for greater resilience against supply chain volatility. To achieve this, a concerted effort is required in the battery research community, bridging the gap between academia and industry.