Advances in battery grade nickel sulfate 2026 Separation and Purification T

Precisely engineered battery-grade precursors, defined by stringent specifications regarding metal composition, particle morphology, and purity levels, are essential for synthesizing cathode materials for rechargeable batteries with superior electrochemical performance. The purpose of this review is to examine recent advancements, challenges, and future directions in the synthesis of battery-grade nickel sulfate, a key precursor for cathode active materials. Various crystallization techniques, including evaporative, cooling, antisolvent crystallization, and innovative methods like eutectic freeze crystallization, are evaluated for their efficiency in achieving the required chemical purity. The removal of magnesium, which inhibits the formation of extra pure α-nickel sulfate hexahydrate, is identified as a critical step and discussed in detail, along with strategies for minimizing other impurities like sodium and chlorine. The review also provides an in-depth analysis of solvent extraction (SX) techniques, highlighting the importance of selecting appropriate extractants and optimizing process conditions to produce high-purity battery-grade final products without the need for subsequent crystallization or electrowinning. The novel synergistic solvent extraction systems and two-circuit processes are emphasized as efficient methods for the simultaneous extraction of nickel and cobalt, thereby simplifying the production process and reducing costs. Overall, this review identifies the critical factors and technological advancements in nickel sulfate production that contribute to improved performance and cost-efficiency in lithium-ion batteries.