钠电池起火的灭火方法有哪些？

What are the fire extinguishing methods for sodium-ion batteries?

钠电池起火分为单体电芯、模组、PACK 不同火情等级，燃烧伴随电解液可燃蒸汽、金属钠微量析出，严禁直流水、泡沫水基灭火剂，需分级处置。初期小范围电芯冒烟小火，首选 D 类金属干粉灭火器，干粉隔绝氧气，抑制钠与水、氧气放热反应，近距离持续喷射覆盖起火部位，同步切断电池高压回路，移除周边可燃物料隔离火源。模组中等火情，采用大量干沙、石墨粉、蛭石完全掩埋燃烧区域，隔绝空气终止热链式反应，掩埋厚度不低于 10 厘米，等待至少 2 小时待内部完全降温再清理，防止复燃。大规模 PACK 热失控火灾，配备专用钠电池灭火柜 / 密闭降温水箱，将整包浸入低温密闭纯水装置（隔绝空气环境），利用低温持续吸热控温，杜绝氧气接触金属钠；无专用设备时远距离持续喷射 D 干粉，同时对周边未燃烧 PACK 大量干沙覆盖防护，阻断热蔓延。严禁操作：禁止自来水、泡沫、二氧化碳直喷，水接触析出金属钠会剧烈爆炸；禁止徒手挪动高温起火电池，防止穿刺扩大火情；禁止高温电池露天暴露，必须密闭隔氧冷却。火情扑灭后不能立刻拆解，需静置 24 小时以上确认无复温复燃风险，再转运至危废处置仓，全程做好人员隔热防护，佩戴耐高温防护面罩、防腐蚀手套。

Sodium-ion battery fires are categorized into single cell, module and PACK fire grades. Combustion produces flammable electrolyte vapor and trace precipitated metallic sodium. Water-based extinguishing agents such as tap water and foam are strictly prohibited, and classified disposal is required. For initial small smoldering cell fires, Class D metal dry powder fire extinguishers are the first choice. Dry powder isolates oxygen and inhibits exothermic reactions between sodium, water and oxygen. Continuously spray the burning area at close range, cut off the high-voltage circuit of the battery simultaneously, and remove surrounding combustibles to isolate fire sources. For moderate module fires, completely bury the combustion zone with a large amount of dry sand, graphite powder or vermiculite to block air and terminate thermal chain reactions, with a burial thickness of no less than 10 cm. Wait at least 2 hours for full internal cooling before cleaning to avoid re-ignition. For large-scale PACK thermal runaway fires, use dedicated sodium battery fire cabinets or sealed low-temperature water tanks. Submerge the whole pack in a sealed low-temperature water device with oxygen isolation to absorb heat continuously and prevent contact between oxygen and metallic sodium. Without dedicated equipment, spray Class D dry powder from a long distance and cover unburned PACKs with plenty of dry sand to block thermal spread. Forbidden operations: Never spray tap water, foam or carbon dioxide directly, as contact between water and precipitated sodium metal causes violent explosions. Do not move high-temperature burning batteries by hand to avoid puncture and fire expansion. High-temperature batteries must not be exposed to open air and require sealed oxygen-isolated cooling. After fire suppression, disassembly cannot be carried out immediately. Leave the batteries standing for more than 24 hours to confirm no reheating or re-ignition risks before transferring to hazardous waste warehouses. All personnel shall wear high-temperature resistant masks and anti-corrosion gloves for full thermal protection.