Nickel Sulphides vs. Nickel Laterites: Which is Better for Batteries and Why?

Introduction

Nickel, a critical component in the rapidly expanding electric vehicle (EV) and renewable energy sectors and plays a pivotal role in the development of high-performance batteries. As the demand for nickel continues to surge, understanding the differences between two primary sources of nickel extraction (laterites and sulphides) is crucial when deciding where to invest in the mining space. This article will look at the distinctions between nickel laterites and nickel sulphides and delves into the question of which type of nickle is better suited for battery applications.

Nickel Laterites

Nickel laterites are an important source of nickel for various industries, including the production of stainless steel and, more recently, the manufacturing of batteries for electric vehicles and renewable energy storage systems. Nickel laterites are geological formations that develop over extended periods through the weathering of ultramafic rocks, which are rich in minerals like olivine and pyroxene. This weathering process occurs under tropical climates like Indonesia and the Philippines, where high temperatures and significant rainfall contribute to the breakdown of these rocks. The rainwater is enriched with oxygen and carbon dioxide and interacts with the minerals in the rocks, leading to chemical reactions that leach the soluble elements like magnesium from the matrix leaving behind the nickel, iron, silicon and aluminum to be concentrated. Over time, distinct layer or profiles form within the laterite deposit. As an example, The uppermost part is called the limonite zone. This zone contains predominantly nickel in the form of nickel oxide and hydroxide accumulates. .

Laterites are generally found close to the Earth’s surface, often within the top few tens of meter,s but that’s not to say laterites are not found deeper aswell. However, generally speaking, this proximity to the surface makes them more accessible for mining operations compared to generally deeper-seated sulphide deposits. As noted above Laterites contain substantial amounts of other elements such as Iron, silicon and aluminum. The presence of these impurities creates challenges for the separation of these elements and requires high pressure acid leaching. This process can be costly and requires sophisticated and energy-intensive processes.

While these deposits are valuable sources of nickel, their composition presents challenges in the extraction and processing phases for use in battery applications. Advances in technology and ongoing research aim to optimize the recovery of nickel from laterites to meet the growing demand in the battery industry but the infrastructure is not quite there

Nickel Sulphides

Nickel sulphide deposits originate from magmas enriched in nickel, which intrude into the Earth’s crust. During the cooling and solidification of molten rocks over time the minerals begin to crystalize in a process known as crystal fractional crystallization. Nickel, being a siderophile element (affinity for iron), tends to concentrate in the residual liquid phase, leading to the formation of nickel-rich sulphide minerals. As the cooling and crystalization occurs, the sulphide minerals segregate from the host rock and accumulate in specific zones which can be found at surface and traced at depth up to several kilometers of the earths surface. Mining at greater depths can be challenging but the high tonnage open pit model for mining these deposits happens well in advance of any underground operations.

One of the main factors that differentiate Laterites and suphides is grade. While on surface it would appear that laterites have higher grades, but due to the metallurgical restraints, sulphides actually contain more nickel as it is in a more concentrated state because of fractional crystallization. Also, the reduced impurity levels simplifies the metallurgical processing steps required to extract nickel from the ore. Traditional mining methods and flotation processes are commonly employed for extracting nickel from sulphide ores. However, recent work from companies like Canada Nickel and FPX have highlighted advancements in the metallurgical processing showing promising recovery rates for lower grade sulphides.

Another added benefit of sulphides is that mine tailings are generally non acid generating and much cleaner in context to laterites. Having non acid generatied tailings saves alot of money on the disposal of waste and neutralization of the acid in the tailings. Simultaneously, while being cleaner and more cost effective, Nickel sulphide deposit generally contain brucite, a mineral that naturally sequesters carbon. New studies in this field are paving the way for netzero carbon mining operations as companies have figured out how to use the tailings to permanently sequester the carbon.

With these more recent advancements in mining technology, companies are starting to unlock the potential of lower grade nickel sulphides, contributing to their significance in meeting the demand for nickel in various industries, particularly in the production of batteries for electric vehicles and renewable energy storage systems.

Battery Applications

The selection between nickel laterites and nickel sulphides for battery applications involves a careful consideration of multiple factors, each of which plays a crucial role in determining the most suitable source of nickel. Let’s take a look at some of the determining factors;

    Cost Considerations:

• Nickel Sulphides: Generally, nickel sulphides are considered more economically viable for battery applications due to their higher nickel content and the relatively simpler extraction processes. Traditional mining methods, such as underground mining and flotation, are commonly used and are often less costly than the techniques required for laterites.
• Nickel Laterites: While laterites may have a lower upfront mining cost, their processing challenges, especially the need for high-pressure acid leaching to extract nickel, can make the overall cost of production higher. However, ongoing advancements in technology aim to improve the cost-effectiveness of laterite processing.

    Environmental Impact:

• Nickel Sulphides: Sulphide deposits have a lower environmental impact compared to laterites. The extraction process for nickel sulphides often involves less chemical-intensive methods, leading to reduced environmental disturbance and have the added bonus of being able to neutralize their carbon output. However, sulphide mining can still have environmental consequences, but such risks require proper management practices and can be mitigated through responsible mining practices.
• Nickel Laterites: Laterite mining and processing can pose environmental challenges, particularly due to the use of chemicals in the HPAL process. The disposal of waste and managing the environmental impact of large-scale laterite operations requires careful planning and adherence to environmental regulations.

    Battery Technology Requirements:

• Nickel Sulphides: The higher nickel content and lower impurity levels of sulphide ores make them attractive for certain battery chemistries, such as nickel-cobalt-manganese (NCM) and nickel-cobalt-aluminum (NCA), commonly used in electric vehicles. These chemistries benefit from the higher energy density associated with nickel-rich cathodes.
• Nickel Laterites: Laterites are also currently being used in NMC batteries which are prevalent in electric vehicles and stationary energy storage systems..

    Global Availability:

• Nickel Sulphides: Sulphide deposits are found in various locations globally, including Canada, Russia, Australia, and other regions. This widespread distribution enhances the security of supply and reduces dependency on specific mining regions.
• Nickel Laterites: Laterite deposits are concentrated in specific tropical regions like Indonesia and the Philippines. This geographical concentration may pose challenges related to supply chain resilience and geopolitical factors, and high carbon footprint left behind from the coal power generating plants used to power the processing facilities.

    Technological Advances:

• Nickel Sulphides: Traditional mining methods and flotation processes are well-established for nickel sulphides. Ongoing technological advancements in exploration, mining, and processing contribute to the continuous improvement of efficiency and environmental performance.
• Nickel Laterites: Continuous research and development efforts are underway to enhance the processing efficiency of laterite ores, making them more competitive and sustainable. Technological innovations may influence the attractiveness of laterites for battery applications in the future.

Global Markets

Recently listed as a critical mineral in North America, both the Canadian and American governments are keen on developing projects to supply the growing market. Historically Nickel supply has proven to be volatile due to factors such as geopolitical tensions, mining disruptions, and changes in government policies and there have been growing concerns about the sustainability of nickel production, especially regarding environmental impacts and ethical mining practices. Indonesia, in particular, has been increasing its nickel production capacity, driven by the growth of nickel pig iron (NPI) production and investments in battery-grade nickel production, but the carbon footprint is incredibly high as the country relies heavily on coal to generate power. Due to the volatility of the nickel supply market itself, nickel prices can experience significant fluctuations in the speculative trading in commodity markets.

Conclusion

In the evolving landscape of battery technology, the choice between nickel laterites and nickel sulphides is not a one-size-fits-all scenario. Both sources have their advantages and challenges, and the decision ultimately depends on a combination of economic, environmental, and technological factors. As the demand for nickel continues to rise, ongoing research and innovation will likely play a pivotal role in optimizing the extraction and processing of both nickel laterites and sulphides to meet the evolving needs of the battery industry. However, if we were to pick one over the other, sulphides carry a distinct advantage in various categories and are ultimately the better choice to supply the rapidly expanding EV market.

Authored by: Mike Coyle