Electrochemical De-intercalation/Intercalation system (EDIs) has attached much attention for lithium extraction from brines. However, the preparation of the matched olivine-FePO₄ cathodes faced various problems. Herein, a simple and efficient method by using sodium persulfate for the preparation of olivine-FePO₄ was proposed, and the optimal operation conditions (30–40 °C, 0.05–0.10 M Na₂S₂O₈, and 1.5–2 h) was obtained. Furthermore, the relationship between the open-circuit voltage and solution redox potential with the de-lithiation rate was determined, and the value of the solution redox potential can be used for the online monitoring of the preparation of FePO₄ electrode. Additionally, the prepared FePO₄ electrode exhibited good selectively and cycle performance for lithium extraction. Using it as cathode to extract lithium from West Taijinar brine, the Mg/Li ratio decreased from 54.27 in the brine to 1.65 in obtained anolyte, and the recovery rate of Li⁺ in brine reached 85.30%. Besides, the average current density of the extraction process reaches 15.65 and 13.11 A·m⁻² respectively. In summary, this electrode preparation method has been introduced to be of high preparation efficiency and easy to control, which would be more suitable for industrial applications.

电化学脱嵌/嵌入系统 (EDI) 对从盐水中提取锂给予了很多关注。然而，匹配的橄榄石-FePO ₄阴极的制备面临各种问题。在此，提出了一种简单高效的过硫酸钠制备橄榄石-FePO _{4 的}方法，并给出了最佳操作条件（30-40 °C，0.05-0.10 M Na ₂ S ₂ O ₈，1.5-2 h ) 获得。此外，确定了开路电压和溶液氧化还原电位与脱锂速率的关系，溶液氧化还原电位值可用于FePO ₄制备的在线监测电极。此外，所制备的FePO ₄电极表现出良好的锂提取选择性和循环性能。用它作为阴极从西泰吉纳尔卤水中提取锂，Mg/Li比从卤水中的54.27下降到得到的阳极液中的1.65，卤水中Li ⁺的回收率达到85.30%。此外，提取过程的平均电流密度分别达到15.65和13.11 A·m ^-2。综上所述，该电极制备方法制备效率高，易于控制，更适合工业应用。