什么是钠电池的普鲁士蓝材料？

What is Prussian blue material for sodium-ion batteries?

普鲁士蓝类似物 PBAs 是三大主流钠电池正极材料之一，属于金属有机配位框架晶体，通用化学通式 NaxM [M’(CN) 6]?nH2O，内部拥有三维贯通超大开放晶格通道，钠离子迁移阻力极低，快充倍率性能十分突出。材料合成工艺流程简单，核心金属元素铁、锰地壳储量极大，原材料生产成本是三类正极中最低，低温放电性能优异，-20℃仍可保留八成以上容量，适配太阳能路灯、外卖电动车、户用平价储能等成本敏感型场景。晶体内部自带结晶水是决定循环寿命核心变量，量产必须配套精准低温真空脱水工序严格控制水分含量。材料核心短板是晶格内部结晶水长期循环会逐步析出，破坏三维骨架结构，造成容量持续衰减，循环上限普遍在 3000 次以内，不及聚阴离子材料。综合性价比优势明显，是现阶段钠电池市场放量主力正极，适合中低端低速动力、分布式储能大批量订单，高端长时电网储能则优先选用聚阴离子体系。

Prussian Blue Analogues (PBAs) are one of the three mainstream cathode materials for sodium-ion batteries, belonging to metal-organic coordination framework crystals with the general chemical formula NaxM [M’(CN) 6]?nH2O. They feature interconnected three-dimensional oversized open lattice channels inside with extremely low sodium ion migration resistance and outstanding fast-charging rate performance. The material boasts a simple synthesis process. Its core metallic elements iron and manganese have massive crust reserves, leading to the lowest raw material production cost among three cathode types. It delivers excellent low-temperature performance with over 80% capacity retention at -20℃, suitable for cost-sensitive scenarios such as solar street lamps, food delivery electric vehicles and low-cost household energy storage. Intrinsic crystal water inside crystals acts as the core variable determining cycle life, and mass production must adopt precise low-temperature vacuum dehydration processes to strictly control water content. Its key shortcoming lies in gradual precipitation of crystal water from lattices during long-term cycling, which damages the three-dimensional framework and causes continuous capacity fading, with a general cycle limit below 3000 times, inferior to polyanion materials. With remarkable comprehensive cost-performance, PBAs serve as the mainstream cathode for market volume expansion of sodium-ion batteries at present, fit for mass orders of mid-to-low-end low-speed power and distributed energy storage, while polyanion systems are prioritized for high-end long-duration grid energy storage.