An overview of lithium resources, geochemistry, exploration, extraction, processing, and applications with a focus on electric vehicles

Today, the demand for critical metals like lithium has enhanced significantly, leading to greater exploration, extraction, and utilize these metals. In this comprehensive review, we discuss the different types of lithium resources, minerals, exploration, extraction, processing, and applications. Pegmatites, sedimentary deposits, and brines are the main sources of lithium. One of the most important applications of lithium is in the battery industry, especially in electric vehicle batteries. The use of these batteries is increasing day by day, so it is important to explore more lithium reserves. Based on the global consumption and demand for lithium, it is necessary to use various exploration methods, including geology, geophysics, mineralogy, geochemistry, and remote sensing, followed by drilling operations to find new lithium reserves. Pegmatites, brines, and playas in Iran have high potential for lithium deposits. Exploration of lithium deposits in Iran and development of appropriate technologies can transform the country into a regional producer of this strategic metal. Introduction Lithium is a soft, silvery-white alkali metal. It has an atomic mass of 6.941 g/mol, and atomic number 3 which is khnown as the least dense metal, highest electrochemical potential, and highly reactive. In addition, lithium is flammable and tends to reacts with water (form hydroxides) nitrogen, oxygen, and carbon dioxide in the air (Balaram et al., 2024; International Lithium Association, 2023). Lithium can replace magnesium due to its similar ionic and atomic radius. Lithium is found in a variety of geological environments and in the crust and can be extracted through various mining methods, depending on the location and composition of the deposit. Pegmatites, brines, and sedimentary deposits are the most important sources of lithium. Over the past decade, lithium demand has increased due to its use in the lithium-ion batteries industry. Global consumption of lithium in 2024, a 29% increase from consumption in 2023. Global lithium demand is expected to reach nearly 1.8 million tonnes by 2030, almost six times the demand in 2020. Global lithium demand is expected to reach 1.8 million tonnes by 2030, almost six times the demand in 2020. In this study, given the increasing demand for lithium and its extensive applications, an attempt has been made to present an up-to-date global perspective on various aspects of lithium, including its applications, geology, mineralogy, different types of lithium reserves, exploration indicators, analysis methods, extraction of lithium reserves, and finally its position and impact in the global market. Geology and classification of lithium deposits Lithium is enriched in the continental crust with an average crustal value of ~25 ppm. The most important sources of lithium include pegmatites, sedimentary deposits, and brines. Pegmatites are coarse-grained igneous rocks enriched in trace elements, including lithium. Pegmatite deposits are one of the primary sources of the lithium, particularly spodumene. The source granitic magma must be rich in lithium and also undergo extreme fractional crystallisation to form pegmatite deposits (London, 2018; Sykes et al., 2019). Lithium accumulates in the latest differentiates of granitic complexes at their final stage of consolidation and thus gets concentrated in significant amounts in pegmatites. Lithium can also be found in sedimentary deposits, where it is usually associated with clay minerals or evaporites. The sedimentary lithium deposits can be divided into two categories: (1) land-based sedimentary deposits, and (2) deep-sea sedimentary deposits. Lithium can be found in brine deposits, which are formed by the evaporation of saline water in arid regions. These deposits are rich in lithium salts such as lithium chloride, lithium carbonate, and lithium hydroxide. Lithium brine deposits are formed over millions of years through a complex combination of geological and hydrological processes involving evaporation, mixing, halite, and hectorite dissolution, and precipitation (Munk and Jochens, 2011; Munk et al., 2016). These deposits are typically found in regions with arid or semi-arid climates, where the rate of evaporation is higher than the rate of precipitation. Discussion and Result Based on the lithium demand, especially in the manufacture of various types of batteries, research to further explore lithium reserves is so important. The largest amount of lithium reserves is in the brine type in Bolivia and Argentina (21 and 20 million tons, respectively), and the smallest amount is in the pegmatite type reserve (0.1 million tons) in Australia. Australia and Chile also have the highest levels of lithium mining. The highest level of processing and production of electrochemical products and batteries is in China (Stringer, and Millan, 2019). The potential supply gap looms large. Projections indicate that by 2034, global demand for lithium could be 6.5 times greater than in 2023, further widening the supply-demand imbalance. By 2029, the industry could face a tipping point where demand far outstrips supply, creating significant challenges for the global energy transition. This impending shortage highlights the critical need for innovative, scalable, and environmentally responsible methods to extract lithium to meet future demand. The electric vehicles need is increasing year by year. Using these types of vehicles will help reduce air pollution and protect the environment. Lithium-ion battery demand is expected to grow by about 27 percent annually to reach around 4700 GWh by 2030. In 2024, the global electric vehicle market had significant changes. Chinese car company BYD took the top spot as the largest electric vehicle manufacturer, followed by Tesla in second place. In Iran, the presence of brines and playas located in the Zagros and Central Iran zones, especially in desert areas, has high potential for lithium deposits. Hectorite in clay deposits should be prioritized for lithium exploration. Exploration of lithium deposits in Iran and development of appropriate technologies can transform the country into a regional producer of this strategic metal.