Nickel is a fundamental component in modern energy storage systems, particularly in the lithium-ion batteries that power electric vehicles (EVs) and large-scale grid applications. The metal’s unique properties, including its ability to operate under high voltages and its high specific energy, make it a preferred material for maximizing battery performance and capacity. Nickel-based chemistries are used across applications ranging from consumer electronics to utility-scale energy projects.
Nickel’s Role in Enhancing Energy Density
The primary reason for nickel’s prominence is its ability to directly increase the cell’s energy density. Nickel resides in the cathode, the positive electrode material that stores and releases lithium ions. Nickel facilitates this process by undergoing a two-electron redox chemistry, which allows the cathode to accommodate a higher number of lithium ions. This translates directly into a larger storage capacity per unit of weight, enabling EVs to achieve a longer driving range without increasing battery size. Nickel atoms also maintain the structural integrity of the layered oxide cathode, preventing crystal collapse when lithium is extracted.
Major Battery Chemistries Utilizing Nickel
Nickel is a component in two dominant lithium-ion chemistries: Lithium Nickel Manganese Cobalt Oxide (NMC) and Lithium Nickel Cobalt Aluminum Oxide (NCA). The composition is defined by the ratio of transition metals; for example, NMC 5:3:2 represents the proportion of nickel, manganese, and cobalt. NCA batteries prioritize maximum range and energy output, often containing around 80% nickel, with aluminum used to stabilize the highly reactive structure. NMC batteries use manganese to improve thermal stability, offering a good balance between energy density and longevity.
Nickel-Metal Hydride (NiMH)
Beyond modern lithium-ion cells, nickel was the active material in the earlier rechargeable technology called Nickel-Metal Hydride (NiMH) batteries. These batteries use nickel oxyhydroxide as their cathode and were the original power source for early hybrid electric vehicles. Although NiMH batteries have a lower energy density than current lithium-ion cells, their inherent robustness and safety features mean they are still employed in some hybrid models.
The Manufacturing Trend Toward High-Nickel Cathodes
The battery industry shows a steady progression toward cathodes with higher nickel concentrations, shifting to nickel-rich formulations such as NMC 8:1:1 (80% nickel). This change is driven by the demand for greater energy density in electric vehicles, allowing manufacturers to boost capacity without increasing battery size. The trend is also motivated by economic considerations surrounding cobalt, which is expensive and has a volatile supply chain. Maximizing the nickel percentage substantially reduces the required amount of cobalt, lowering overall manufacturing costs. The industry is researching ultra-high nickel formulas, exceeding 90% nickel, to further minimize cobalt usage.
Sourcing and Sustainability Considerations
The rapid adoption of nickel-rich batteries has strained the raw material supply chain, raising sustainability concerns. Meeting the demand for high-purity nickel sulfate requires complex, energy-intensive mining and processing, often carrying a significant carbon footprint. Indonesia, a major source, faces environmental concerns regarding deforestation and mining waste management. To address this, the industry is focusing on creating a circular supply chain through battery recycling. Advanced facilities are being developed to recover valuable metals, including nickel, from spent EV batteries, which is expected to reduce reliance on new primary mining.