A process was developed to produce battery-grade lithium carbonate from the Damxungcuo saline lake, Tibet. A two-stage Li 2 CO 3 precipitation was adopted in a hydrometallurgical process to remove impurities. First, industrial grade Li 2 CO 3 was obtained by removing Fe 3+, Mg 2+, and Ca 2+ from a liquor containing lithium.
To replace the use of sodium slats, ammonium salts or NH 3 ·H 2 O−CO 2 have also been adopted as the carbonate source to synthesis battery-grade Li 2 CO 3, and the X-ray diffraction (XRD) result indicated a high purity (Lu et al., 2022).
Production steps in lithium-ion battery cell manufacturing summarizing electrode manufacturing, cell assembly and cell finishing (formation) based on prismatic cell format. Electrode manufacturing starts with the reception of the materials in a dry room (environment with controlled humidity, temperature, and pressure).
A purity of 99.7–99.8 wt% was achieved in the ammonia-based systems. Battery-grade lithium carbonate (Li 2 CO 3) with a purity of higher than 99.5 wt% is of great importance as a high value-added lithium salt. However, influences of different reaction systems and process control on product purity remain unclear.
2.1. State-of-the-Art Manufacturing Conventional processing of a lithium-ion battery cell consists of three steps: (1) electrode manufacturing, (2) cell assembly, and (3) cell finishing (formation) [8, 10].
Although industrial-grade Li 2 CO 3 can be purified and crystallized several times to increase its purity, a low Li 2 CO 3 recovery of less than 75% is usually obtained, since Li 2 CO 3 is slightly soluble in water (Liu, Zhao, et al., 2021). Therefore, one-step synthesis of battery-grade Li 2 CO 3 has attracted extensive attention.