钠电池的碳足迹是什么？

What is the carbon footprint of sodium-ion batteries?

钠电池碳足迹指一块完整钠离子电芯从矿产原料开采、材料合成、电芯制造、PACK 集成、运输、使用直至报废回收全生命周期内，直接与间接温室气体二氧化碳总排放量，覆盖上游资源、中游生产、下游应用、末端回收四大碳排放环节。上游碳源：钠矿、钒矿、农林生物质硬碳原料开采运输，正极、电解液、硬碳高温，是全周期最大碳排放来源，占总足迹 55%~65。中游制造：配料、涂布、辊压、化成等设备电力、车间供暖蒸汽、生产辅料制备带来间接排放，占 20%~28。下游流通：成品 PACK 陆路、海运运输燃油碳排放，占 5%~10。使用阶段：依托光伏、风电绿电充放电可大幅抵消碳足迹，火电配套则增加额外排放；末端回收：拆解、冶金再生能耗产生少量碳排放，同时再生材料替代矿产可显著削减新增碳足迹。对比三元、磷酸铁锂，钠电池无需锂、钴高碳矿产开采，农林基硬碳属于负碳原料，同等容量碳足迹降低 30%~45，尤其长时储能场景减排优势突出。碳足迹核算用于双碳项目申报、出口欧盟碳关税、储能电站绿色认证，是新型低碳储能核心量化指标。

The carbon footprint of a sodium-ion battery refers to the total direct and indirect greenhouse gas carbon dioxide emissions (unit: kg CO?eq) throughout the full life cycle of a complete cell, covering mineral mining, material synthesis, cell manufacturing, PACK integration, transportation, operation and waste recycling. It includes four emission segments: upstream resources, midstream production, downstream application and end recycling. Upstream carbon sources account for 55%~65% of total footprint, the largest contributor. CO? is generated from thermal power consumption during mining & transportation of sodium ore, vanadium ore and biomass hard carbon, as well as high-temperature synthesis of cathodes, electrolytes and hard carbon. Midstream manufacturing indirect emissions from equipment power, workshop heating steam and auxiliary material production make up 20%~28%. Downstream circulation fuel emissions from land and sea transport of finished PACKs account for 5%~10%. Operation stage: Charging with green PV & wind power drastically offsets carbon footprint, while thermal power matching adds extra emissions. End recycling generates minor emissions from disassembly and metallurgy, yet recycled materials replace mineral feedstock to cut new carbon output significantly. Compared with ternary and LFP batteries, sodium-ion cells eliminate high-carbon lithium & cobalt mining. Biomass hard carbon acts as carbon-negative feedstock, reducing equivalent carbon footprint by 30%~45% at the same capacity with prominent emission reduction advantages for long-duration storage. Carbon footprint calculation supports dual-carbon project application, EU carbon border tax export and green certification of energy storage power stations, serving as a core quantitative indicator of low-carbon new storage technologies.