Lithium-ion based energy storage is one of the leading storage technologies that enables sustainable and emission-free energy. 近年来, 由于它们的功率密度, 表演, 经济优势, 锂离子电池储能系统 (BESS) have seen an increase in use for peak shaving and grid support in residential, 商业, 工业, 以及公用事业应用. 自2019年以来，BESS能源容量增长了 在美国增长了200%以上.S., with developers and operators expected to add at least 9 GW of capacity in 2022.
与锂离子电池相关的爆炸风险
不幸的是，作为的使用 锂离子电池储能系统 expands, field failures resulting in fires, explosions and toxic exposure have become more prevalent. Although the technology is considered safe and continuously improving, lithium-ion batteries contain flammable electrolytes that can create unique hazards when battery cells become compromised. 收费过高, 过热, 和热, 机械, and electrical abuse can cause a short circuit leading to thermal runaway and the sudden release of thermal and electrochemical energy. 在放热反应过程中, large amounts of flammable and potentially toxic battery gas is generated and liberated into the BESS enclosure. 释放的气体主要含有氢, 哪一种在各种条件下都是高度易燃的. This may create an explosive atmosp在皇家88账户注册里 in the battery room or storage container.
NFPA 855/69锂离子BESS爆炸控制要求
To address the safety issues associated with lithium-ion energy storage, NFPA 855 and several other fire codes require any BESS the size of a small ISO container or larger to be provided with some form of explosion control. 皇家88账户注册包括步入式单元，柜式BESS和建筑物. One way to achieve this is by outfitting the BESS with an explosion prevention system that meets NFPA 69 requirements.
NFPA 69 requires the combustible concentration within the BESS enclosure to be maintained at or below 25% of the lower flammable limit (LFL) for all foreseeable variations in operating conditions and material loadings. 为了达到皇家88账户注册个标准, a 机械 exhaust ventilation/purge system is typically used to remove flammable battery gas from the ESS space and replace it with clean air through intake louvers. Simulations are often preferred to determine if an explosion prevention system can effectively mitigate gas concentrations according to NFPA 69 standards.
Designing BESS Explosion Prevention Systems Using Computational Fluid Dynamics (CFD) Explosion Simulations
CFD methodology can assist with the 表演-based design of explosion prevention systems containing exhaust systems. CFD is a simulation tool that produces predictions of fluid-flow phenomena based on the laws governing fluid motion (i.e.(质量、动量和能量). Frequently used for simulating the accidental release of flammable gas, CFD simulations can help demonstrate the evolution of gas release as a function of space and time. One advantage over analytical steady-state methods is that the CFD simulation can capture the initial transient of the event. 皇家88账户注册为所需的检测时间提供了重要皇家88账户注册.
A variety of metrics can be used to quantify the global parameters in CFD simulations, 例如在一个外壳内的体积分数和质量. 另外, displaying the gas cloud between the LFL and upper flammability limit (UFL) can help quantify the size of the flammable cloud. This detailed information is useful in understanding the consequence of a scenario and designing mitigation measures, 如气体检测和防爆系统.
工艺安全 industries dealing with flammable fluids and explosible dust will often employ CFD for designing explosion prevention systems. 涉及泄漏的不同场景, 浮力泄漏, momentum-driven leaks and a sudden loss of containment can be prescribed using a source term in the CFD explosion simulation. These different leak scenarios require a deep understanding of the flammable fluid, 储存和操作条件, 以及相关的危害. The critical challenge in designing an explosion prevention system for a BESS is to quantify the source term that can describe the release of battery gas during a thermal runaway event. 因此, full-scale fire test data such as from UL 9540A testing are important inputs for the gas release model.
CFD methodology can be extended to design an explosion prevention system for any ESS enclosure. Results can also provide the controlled release rate of flammable and toxic materials which is useful information for first responders and to assess environmental impacts. 点击 在皇家88账户注册里 to learn more about our how our experts can assist with energy storage systems design.