储能型LiFePO4霍克电池灭火剂的热失控抑制性能与应用模拟4电池

当前锂离子电池热失控已成为制约储能体系安全的要害因素，亟需高效救活剂及其体系化使用。本研讨经过全面试验，从多角度评估了不同救活剂对大容量单体锂离子电池的按捺功能。研讨发现液态救活剂（去离子水与水基剂F-500）展示出最优的综合按捺功能，而气态救活剂HFC-227ea与C6救活后，电池表面温度迅速回升，标明存在明显的复燃风险。超细干粉固体救活剂对按捺热失控的作用有限。基于试验成果，研讨进一步对简化储能体系模型开展数值模拟，以阐明细水雾体系要害特征参数（包含喷雾锥角、喷雾强度与雾滴直径）对储能体系电池火灾按捺功能的影响。成果标明，喷雾锥角改变对救活作用影响较小，60°锥角可在覆盖规模与经济可行性之间抵达最优平衡。救活功率与喷雾强度呈正相关，与液滴直径呈负相关。但是，这两个参数均存在临界阈值，超越该阈值后功能进步有限，且可能影响经济性与体系可靠性。本研讨为储能体系的安全防护与工程设计供给了重要辅导。12O, a rapid rebound of the battery surface temperature was observed after extinguishment, implying a considerable risk of re-ignition. The solid extinguishing agent, superfine powder, demonstrated limited effectiveness in suppressing thermal runaway. Based on the experimental findings, numerical simulations were further performed on a simplified energy storage system model to elucidate the influence of key characteristic parameters of a fine water mist system, including spray cone angle, spray intensity, and droplet diameter, on fire suppression performance in the battery fires of energy storage systems. The results show that variations in the spray cone angle exert only a minor effect on suppression effectiveness, while a 60° cone angle achieves a balance between coverage range and economic feasibility. Fire suppression efficiency exhibits a positive correlation with spray intensity and a negative correlation with droplet diameter. However, critical thresholds exist for both parameters, beyond which further performance enhancement is limited and may compromise economic efficiency and system reliability. This study provides important guidance for the safety protection and engineering design of energy storage systems.

引言

跟着全球变暖与动力危机的两层应战日益严峻，可再生清洁动力被赋予了更高的期望和要求。锂离子电池（LIBs）作为可再生动力存储的理想材料，凭仗其高能量密度、长循环寿命、低自放电率及环境友好性等优势[1][2]，已在电化学储能体系（ECESS）中得到广泛使用。其间，磷酸铁锂（LFP）电池因其更高的本征安全性、更长的循环寿命和更优的经济性体现[3]而备受喜爱。但是，储能体系（ESS）中LFP电池因热失控（TR）引发的频频火灾事故，已成为制约其进一步发展和大规模使用的主要障碍[4]。
大量研讨和证据标明，锂离子电池在电滥用、热滥用和机械滥用等反常工况下更易发生热失控（TR）。该进程随同高温、浓烟、可燃气体乃至喷发火焰[3][4][5][6][7]。在电化学储能体系中，一般经过串联并联多个单体锂离子电池组成满足容量与电压需求的电池组。但是由于多米诺效应，当某一单体电池发生热失控时，剩余电池在高温与火焰影响下极易被扳机（Trigger）引发连锁热失控，终究导致火灾蔓延至整个电池组。
为进步锂离子电池（LIBs）的热安全性，当前研讨进展可归纳为三大类：本征安全、进程安全和火灾安全[8]。本征安全指经过改进电池组件来下降内部故障概率[9][10][11]，而进程安全则触及开发电池热办理体系（BTMS）以保证电池稳定运转[12][13][14]。但是这些方法无法完全消除火灾事故的发生。火灾安全作为储能安全的终究保障至关重要[8]。锂离子电池（LIB）火灾具有可燃物杂乱、扑救困难且易复燃等特色，这为寻找和使用高效救活剂与技术带来了严重应战。
关于固体救活剂，孟等人[15]发现ABC干粉能有用快速熄灭22安时磷酸铁锂(LFP)电池明火，但电池内部可能发生复燃。针对气体救活剂，王等人[16]研讨标明七氟丙烷(HFC-227ea)可有用熄灭50安时钛酸锂(LTO)电池及其模组火灾，但无法阻止电池内部热失控(TR)的链式反应，导致火势熄灭后出现复燃现象。臧等人[17]进一步发现HFC-227ea在熄灭243安时LFP电池火灾时仍存在困难。刘等人[18][19]与王等人[6]研讨标明Novec-1230(C6O)可快速熄灭电池火灾，但其冷却功率相对较低。火灾熄灭后，电池仍处于极高温状况。他们还比较了不同剂量C12O的按捺作用，发现基于自由基反应，少量C6氧气实际上会促进焚烧。关于液体救活剂，Liu等[20]、[21]、[22]发现细水雾能有用阻止锂离子电池热失控传播，并展示出优异的冷却功能。Xu等[23]、[24]研讨标明水雾可有用熄灭电池火灾，其救活效能优于二氧化碳12和HFC-227ea。Zhao等[25]对比了三种救活剂对18650型锂离子电池火灾的按捺作用，成果显现水雾具有最高的冷却功率，而干粉与C62等气体。但是，Larsson等[26]研讨发现，跟着火势加重，细水雾的微滴尺寸与热羽流效应会限制雾滴穿透烟雾抵达火源区的能力。Zhang等[27]则发现，尽管水雾能熄灭锂离子电池火灾并下降电池表面温度，但加水会导致CO、H2等气体浓度上升。12以及HF。部分研讨还标明，在水雾中增加增加剂可增强其对锂离子电池的救活效能。Zhu等[28]发现，经过在水雾中增加一定比例的表面活性剂，能快速下降焚烧温度并明显缩短救活时刻。Wang等[29]则探求了物理与化学增加剂在锂离子电池救活进程中的作用机制。成果标明：物理增加剂经过下降水雾表面张力与雾滴尺寸，增强了雾场中的吸热冷却效应、辐射热障效应及窒息效应；化学增加剂则经过分化火场可燃气体并捕获电池焚烧反应中的自由基，进步了救活功率。Yuan等[30,31]研讨了F-500救活剂的按捺机理。浓度为3%的F-500溶液可经过吸收与热失控（TR）相关的特征气体并展示杰出的冷却功能，从而按捺锂离子电池（LIB）火灾。2 and HFC-227ea. Zhao et al. [25] compared the suppression effects of three fire extinguishing agents on 18,650 LIB fires. The results showed that water mist had the highest cooling efficiency, while dry powder and C6F12O were ineffective in preventing the propagation of TR in LIBs. However, Larsson et al. [26] found that as the fire intensifies, the fine droplet size of the water mist and the thermal plume effect limit the ability of the mist droplets to penetrate the smoke and reach the fire source area. Zhang et al. [27] discovered that while water mist can extinguish LIB fires and reduce the surface temperature of the battery, adding water leads to an increase in the concentrations of CO, H2, and HF. Some studies have also shown that adding additives to water mist can enhance its fire extinguishing effectiveness for LIBs. Zhu et al. [28] found that by adding a certain proportion of surfactants to water mist, the combustion temperature could be rapidly reduced, and the extinguishing time could be significantly shortened. Wang et al. [29] investigated the roles of physical and chemical additives in the fire extinguishing process of LIBs. The results indicated that physical additives, by reducing the surface tension and droplet size of the mist, enhanced the heat absorption and cooling, radiant heat barrier, and oxygen starvation effects in the mist field. Chemical additives improved the fire extinguishing efficiency by decomposing the combustible gases at the fire scene and capturing free radicals in the battery combustion reaction. Yuan et al. [30], [31] studied the suppression mechanism of the F-500 fire extinguishing agent. A 3% concentration of F-500 solution can suppress LIB fires by absorbing characteristic gases related to TR and exhibiting excellent cooling performance.
从前研讨主要集中于小容量电池火灾，且缺少统一标准来对比各类救活剂对锂离子电池火灾的按捺作用，导致所得结论缺少满足说服力。本研讨的创新点在于经过试验对比揭示了气体、液体及固态救活剂对大容量磷酸铁锂电池火灾的按捺效能与作用机制。此外，在储能体系层面，经过数值模拟剖析了具有最佳救活功能的救活剂的实际使用作用。研讨成果为高效救活剂的设计开发供给了有价值的建议，同时为拟定储能体系火灾按捺策略供给了明确参阅。这些发现可有用防备或减轻对人员、财产及环境形成的危害。