As the world moves towards a sustainable energy storage economy, the limitations of lithium-ion batteries have become more obvious. Alternative battery chemistries offer an opportunity to diversify clean energy supply chains and take full advantage of the capabilities of battery technology. In this article, we will explore some of the alternatives and their potential to challenge the dominance of lithium-ion.
Global demand for renewable energy solutions continues to increase, with utility-grid applications and renewable energy equipment high on the energy transition agenda. According to the Global Energy Center, battery technology is an essential component of this transition, with scalable technology enabling grid-scale storage of renewable energy for later use. Lithium-ion batteries have become dominant in this field, due to their high energy densities and the technological benefits that have emerged from research into their chemistries.
However, as demand for renewable energy storage grows, concerns are being raised about the safety, limited production capacity, and the environmental impact of lithium-ion batteries. Alternative battery chemistries provide a means of diversifying the energy storage industry and unlocking the full potential of battery technology for sustainable energy storage.
Alternatives to Lithium-ion Batteries
Researchers and companies are investing in high-risk research and development to identify an alternative battery that can challenge the position of lithium-ion as the dominant technology. Among the alternatives are aqueous magnesium batteries, seawater-based batteries, graphene batteries, manganese hydrogen batteries, iron-air batteries, sodium-ion batteries, solid-state batteries and many more.
Each alternative battery chemistry offers specific benefits that address the shortcomings of lithium-ion. Solid-state batteries use solid electrolytes instead of liquid ones, making them safer and more energy-dense than lithium-ion. Seawater-based batteries use the metal and salt in seawater to produce an electrochemical reaction that generates electricity, providing an efficient and carbon-neutral energy-storage solution.
Many of these alternatives also use metals other than lithium, which could help mitigate the vulnerabilities and environmental issues associated with lithium-mining. Magnesium-ion and aluminum dual-ion batteries use lower-cost, earth-abundant metals in their cathode materials, reducing the need for cobalt, nickel, and other rare earth metals.
Sodium-based batteries, such as sodium-sulfur (NAS) batteries, offer advantages such as low cost, high energy density, and scalable technology. They are already in use in niche markets such as military vehicles, but challenges remain regarding safety, performance, and scalability.
In the next section, we will examine the advantages and challenges of these alternative battery chemistries in more detail.
Advantages and Challenges of Alternative Battery Chemistries
Most alternatives to lithium-ion batteries offer advantages such as increased safety, lower cost, and higher energy density. Solid-state batteries, for example, eliminate the need for flammable liquid electrolytes, making them safer for use in electric vehicles (EVs) and other applications. Aqueous magnesium batteries offer very high energy density, with theoretical anode capacity exceeding that of lithium-ion.
However, these benefits come with challenges. Production capacity for many of these alternatives is limited, with many chemistries still being in the development stage. Graphene batteries, for example, are still being researched to improve their performance characteristics and manufacturing capabilities. Solid-state batteries also require some challenging engineering solutions to ensure that they are reliable, safe to use, and can be produced inexpensively.
Scalability is the biggest challenge facing alternative battery chemistries. Researchers and investors are currently navigating the process of bringing these technologies to mass production while ensuring product safety, consistency, and performance. Another challenge is the high cost of some of the raw materials, especially metals such as cobalt, nickel, and lithium, which are in short supply and found in limited geographic areas. Alternative chemistries, such as sodium-ion and potassium-ion batteries, could potentially use more abundant materials, but these come with their unique chemical properties and other issues that still require research to address.
Safety concerns are also present, particularly in chemistries that are still in the research phase. A few years ago, Samsung’s Note 7 experienced a widespread battery failure due to poor battery design, leading to safety concerns and recalls that cost the company billions of dollars. Other alternative chemistries, such as carbon nanomaterial batteries, have the potential to exhibit rapid self-discharge and exhibit electrochemical instability, which could make them problematic for use in energy storage solutions.
Promising Alternative Battery Chemistries
Despite the challenges facing alternative battery chemistries, lithium-sulfur, sodium-ion, and solid-state batteries are among the most promising. Lithium-sulfur technology offers cheaper and lighter batteries with the potential for uses in aviation, personal flying taxis, and electric aircraft by reducing weight and cost. Sodium-ion batteries offer cost, sustainability, and safety advantages in bulk energy storage. They are also promising for use in electric vehicles, where they offer better longevity than conventional lithium-ion batteries.
Solid-state batteries represent ground-breaking technology that has the potential to surpass lithium-ion battery performance, with higher energy densities. They eliminate the need for specific electrode chemicals and can be embedded into flexible substrates. This technology also has the potential to revolutionize the energy storage industry by creating cells that are stackable and contain no flammable materials.
Lithium-sulfur technology, which could potentially replace lithium-ion technology in the aviation industry, is more than four times energy-dense than lithium-ion batteries, offering an unprecedented weight reduction of up to 60%. Researchers are also exploring the potential for solid-state electrolytes to eliminate the risk of battery combustion in EVs and grid-scale battery energy storage systems.
Challenges Facing Commercial Viability
Despite the enormous potential of alternative battery chemistries, their commercial viability remains a significant challenge. One of the most significant challenges is scalability and commercial viability compared to lithium-ion batteries. The economies of scale enjoyed by Lithium-ion batteries are hard to challenge as they dominate the energy storage market and are a proven technology.
Another issue is production capacity, which can be challenging for some alternative metal-ion batteries. Cobalt, nickel, and lithium are necessary elements for lithium-ion battery production, but they are in limited supply and primarily sourced from environmentally unsound metal mining and refining practices. Alternative chemistries like potassium or sodium-ion flow batteries could use more abundant materials like seawater, but as we have seen, this presents unique manufacturing and chemical engineering challenges.
Bringing these new technologies to mass production requires overcoming numerous hurdles. Safety certification is necessary, especially as lithium-ion battery failures continue to make headlines. Supply chain issues need to be addressed, as there remains significant supply chain stress in the renewable energy landscape. Reliability, manufacturability, and cost are also crucial issues, with promising battery chemistries needing to aim for mass production costs of less than $100 per kWh.
Alternative battery chemistries offer enormous potential for revolutionizing the energy storage industry, enabling the transition to a sustainable energy storage economy. However, their commercial viability remains a significant challenge, with the lithium-ion battery’s economies of scale hard to replicate. With ongoing research into alternative materials, engineering, and safety, these chemistries offer promising opportunities for the energy transition. To unlock their full potential, policymakers, researchers, and industry stakeholders must continue working together to overcome the hurdles that currently impede alternative battery technologies.