Reduce Fire Hazard Research Articles

Patterns of Anthropogenic Fire within the Midwestern Tallgrass Prairie 1673–1905: Evidence from Written Accounts

We conducted literature searches of records from Illinois, Indiana, Iowa, Minnesota, Missouri, North Dakota, Ohio, and Wisconsin to create a source bibliography of wildland fire descriptions occurring between 1673 and 1905. A total of 795 landscape fire records were identified within or near the eastern tallgrass prairie–forest transition region, including 32 attributed to Native Americans, 194 to Europeans from spontaneous records in the nineteenth century, and 569 to Europeans from a systematic dataset collected during the late nineteenth and early twentieth centuries in Minnesota. From these historical accounts, we find overwhelming evidence that a two- to three-week period during October and November, known then as “Indian summer,” was the primary wildland fire season. Our records indicate that Native Americans used fire primarily for hunting, whereas Euro-American fires were set to reduce fire hazards near their habitations, to eliminate crop residues, and to facilitate plowing, or they were escapes due to mere carelessness. Only five lightning-caused fires were identified. Individual fires frequently burned thousands of hectares, creating dense smoke, damaging trees, personal property, and occasionally burning inhabitants fatally. South and southwest were the most frequent wind directions during wildfires. Drought years, including 1796, 1819, 1856, and 1871, were characterized by extensive fires, which ultimately resulted in legislation to protect property owners and public welfare. Fire events for the study period are certainly underestimated by this dataset because only large, spectacular, threatening fires were recorded, especially during European settlement. In addition, our estimate of Native American fire frequency and prevalence is less than their historical/expected frequency, due to their widespread population collapse and changed hunting methods following contact and dispossession by Europeans.

Thinning and plantation of resprouting species redirect overstocked pine stands towards more functional communities in the Mediterranean basin

Post-fire regeneration in Pinus halepensis' forests, one of the most abundant vegetation types in the Mediterranean basin, often generates overstocked and vulnerable stands. They accumulate a high fuel load, increasing the risk of further fires, and present high levels of vulnerability due to their reduced seed production. In addition, these dense stands substantially reduce the availability of light and nutrients, which may hinder the recruitment of other species, often generating mono-specific and homogeneous stands, which potentially supply fewer ecosystem services than mixed forests with more heterogeneous structures. In these dense pine stands, management is of high priority to reduce fire hazards and promote their functionality. In overstocked pine stands (>75,000 trees·ha−1), we assessed the long-term effects (10 years) of two thinning levels (600 and 1200 trees·ha−1), in combination with the plantation of Quercus faginea (a resprouter species typical of advanced successional stages in our study area) on 28 above and belowground ecosystem attributes, including fire hazard. After ten years, thinning and plantation interacted to enhance ecosystem attributes associated with disturbance regulation and biodiversity conservation (up to 200%) and food production (up to 90%), while no effects were observed on those attributes related to carbon sequestration and supporting services. These effects were mainly driven by aboveground attributes, as they responded more strongly to our treatments than those belowground. Our results are relevant for the restoration of Mediterranean degraded ecosystems, and show that tree thinning in overstocked pine stands, combined with the plantation of resprouter species, may not only reduce fire risks and accelerate post-fire succession but also enhance the supply of multiple ecosystem services in the long run.

Harvesting Multidirectional Breeze Energy and Self‐Powered Intelligent Fire Detection Systems Based on Triboelectric Nanogenerator and Fluid‐Dynamic Modeling

AbstractFire warning and monitoring are very important for public safety and environmental protection. However, most of the proposed wind energy conversion devices based on triboelectric nanogenerator (TENG) only work for unidirectional and high‐speed wind and face the challenge of fatigue damage and even failure caused by cyclic stress. Moreover, TENG guided by the theory of fluid dynamics needs further exploration. Herein, a flow‐induced vibration effect based TENG (F‐TENG) for continuously capturing and monitoring multidirectional breeze (1.8–4.3 m s−1) is developed to build a self‐powered intelligent fire detection system (SIFDS). A dynamic model is proposed to study the intrinsic interaction between the electrical properties of F‐TENG and wind. Since the model optimized F‐TENG is more adaptable to wind characteristics, it delivers better performance and higher durability compared with previous studies. Relying on the dynamic model and combining the relationship between F‐TENG's electrical output and wind characteristics, a self‐powered visual wind sensing system is obtained. F‐TENG successfully drives some electronic devices to monitor environmental information, which is expected to provide data for SIFDS to reduce fire hazards. This study can provide an in‐depth understanding of the electromechanical conversion mechanism and large‐scale capture and utilization of breeze energy.

Trinity effect of potassium sulfonate-benzimidozale towards self-intumescent flame-retarded polyester with low fire hazards

Additive-type Intumescent flame retardants (IFRs) are widely used in many polymeric materials to reduce fire hazards. However, the migration behavior of IFRs in the long-term use process leads to poor flame retardance durability and undesirable health issue. To address these problems, a novel reactive monomer (MS-K) containing potassium sulfonate and benzimidozale groups was synthesized and chemically linked into the backbones of model polymer (Polyethylene terephthalate, PET). When the PET-copolymer burnt, the sulfonate group worked as acid and gas sources, and the benzimidozale group acted as carbon source. The trinity effect (acid, gas and carbon sources) of benzimidozale-potassium sulfonate structure gave rise to the self-intumescent carbonization behavior of PET matrix. As a result, the formed intumescent char-layer exerted a significant condensed-phase flame retardant effect that can hinder the oxygen exchange, isolate from the heat source and suppress the volatilization of combustible small molecules. Thus, the corresponding PET-copolymer exhibited extremely low fire hazards with UL-94 V-0 rating, a high limiting oxygen index of 32.5 vol%, greatly decreased peak heat release rate (decreased by 58%) and total smoke production (decreased by 39%). The strategy of reactive trinity-macromolecule not only exhibits excellent intumescent flame-retardant effect, but also completely eliminates the migration issue, which represents a promising way to replace the traditional additive-type IFRs.

Highly efficient MXene/Nano-Cu smoke suppressant towards reducing fire hazards of thermoplastic polyurethane

A large number of toxic fumes evolved from polymeric materials are a great threat to human evacuation. The aim of this work is to dramatically reduce the generation of smoke and toxic gaseous products upon polymers burning. A highly efficient titanium carbide/nano-copper (Ti3C2Tx/Nano-Cu) hybrid smoke suppressant was synthesized by interficial adhesion and then incorporated into thermoplastic polyurethane (TPU) to fabricate TPU nanocomposites. The Ti3C2Tx/Nano-Cu hybrid was homogeneously dispersed in the TPU matrix and showed a strong interfacial interaction with the TPU host. Introducing the Ti3C2Tx/Nano-Cu hybrid into TPU led to enhanced high-temperature stability. Furthermore, the smoke production rate, CO production rate and total CO yield of the TPU nanocomposite containing 2 wt% Ti3C2Tx/Nano-Cu hybrid decreased by 66.7%, 51.8% and 52.9%, respectively, compared with those of pure TPU. The reduced fire hazards of the TPU were due to the physical barrier, the catalytic charring and the chemical conversion of Ti3C2Tx/Nano-Cu hybrid.

In-situ preparation of layered zinc N, N’-piperazine (bismethylene phosphonate) functionalizing reduced graphene oxide for epoxy resin with reduced fire hazards and improved thermal/mechanical properties

Layered zinc N, N’-piperazine (bismethylene phosphonate) functionalizing reduced graphene oxide (rGO@ZnPB) was prepared via in-situ method for the reduction of fire hazards of epoxy resin (EP), as well as the improvement on its thermal and mechanical properties. The results reveal a better flame retardancy of rGO@ZnPB than either rGO or ZnPB at the same loading level for EP. Remarkably, EP with 5.0 wt% rGO@ZnPB succeeds to UL-94 V-0 rating, as well as reductions by 38.7%, 30.5%, 33.7% and 33.8% in the peak heat release rate, total heat release, total smoke release and the peak CO production rate, respectively with respect to that of pure EP. Additionally, the thermogravimetric and differential scanning calorimeter results manifest that the thermal stabilities and glass transition temperatures of EP/rGO@ZnPB composites are improved to some extent. Moreover, the incorporation of a small quantity of rGO@ZnPB has some reinforcing effect on the mechanical properties of EP.

FIRE HAZARD AND PHYSICO-MECHANICAL PROPERTIES FOR EPOXY-AMINE COMPOSITES CONTAINING THE [Cu(DETA)(H2O)]SO4·H2O FLAME RETARDANT-HARDENER

Introduction. The rapid growth of production rates and the use of polymer materials in various fields has brought about an increase in the number of fires caused by the ignition of polymer products. Among the most common polymer materials are materials based on epoxy resins. They are used in such industries as construction, electrical engineering and radio engineering, shipbuilding, mechanical engineering, including automotive, aerospace and rocketry, etc. Due to its organic structure, high content of carbon and hydrogen, epoxy polymers are very combustible. Their combustion is characterized by high temperature and more flame propagation rate. And it is accompanied by significant smoke formation and the release of large amounts of toxic products. Therefore, the search for new ways to reduce combustibility and maintain the proper level of performance is one of the priorities in the development and implementation of new epoxy polymer materials in various fields. Purpose. The work aims to obtain epoxy-amine composites and to discover the effect of flame retardant-hardener on their fire hazard and physical and mechanical properties.Methods. In work used Modern research methods. The flame propagation rate was determined by UL94, the coefficient of smoke was measured by ASTM E662-19, physical and mechanical properties were evaluated by measuring parameters such as surface hardness, tensile strength, water absorption and chemical resistance.Results. The parameters of fire danger of epoxy-amine composites with different content of flame retardant (0, 5, 16 and 80 mass parts) were studied. The results of experimental studies showed that the flame propagation rate and the smoke formation coefficient in the mode of smouldering and combustion are minimal for epoxy-amine composites containing 16 and 80 mass parts of flame retardant. Such compositions have higher surface hardness and tensile strength. And they also well as more resistant to water and aggressive environments compared to unmodified ones.Conclusion. The paper presents a simple and commercially attractive method of obtaining epoxy-amine composites con-taining different amounts of flame retardant – copper(II) sulfate. It is necessary, the obtained samples of the composites are homogeneous in structure. These should be considered as individual chemicals, not as mixtures. Chemical bonding of all components of the composites, namely the appearance of additional (compared to the unmodified composite) Cu(II)–N coordination bonds in the polymer framework DGEBA/DETA-CuSO4, is reflected in the enhanced physical and mechanical properties and fire hazard reduction for this type of composite materials.

Fabrication and Mechanism Study of Cerium-Based P, N-Containing Complexes for Reducing Fire Hazards of Polycarbonate with Superior Thermostability and Toughness.

A superior comprehensive performance is essential for the extensive utilization of polymers. Current flame-retardant strategies for polycarbonates (PCs) usually realize satisfied fire resistance at the cost of thermostability, toughness, and/or mechanical robustness. Thus, we report a rare-earth-based P, N-containing complex with a lamellar aggregated structure [Ce(DPA)3] by a coordination reaction between a tailored ligand and cerium(III) nitrate. The results indicate that incorporating 3 wt % Ce(DPA)3 enables the resultant PC composite to achieve UL-94 V-0 rating, with a 55% reduction in the peak heat release rate. Besides, the initial (T5) and maximum (Tmax1 and Tmax2) decomposition temperatures are significantly increased by 21, 19, and 27 °C, respectively, in an air atmosphere. Moreover, the impact strength and elongation at break of the PC composite containing 3 wt % Ce(DPA)3 are greatly increased by 20 and 59%, respectively, relative to pristine PC, while its tensile strength (57 MPa) is still close to that of bulk PC (60 MPa). Notably, this work provides a novel methodology for revealing the evolution mechanisms of chemical structures of vapor and residual products during thermal decomposition, which is conducive to guiding fire and heat resistance modification of PC in the future.

Non-aromatic Si, P, N-containing hyperbranched flame retardant on reducing fire hazards of epoxy resin with desirable mechanical properties and lower curing temperature

Plastic combustion has adverse impacts on air quality and human health. In this work, a novel non-aromatic Si, P, N-containing hyperbranched flame retardant (HPNSi) was synthesized and proposed to epoxy resin. The modified epoxy exhibits not only reduced fire hazards and less smoke production in favor of eco-friendly, but also remarkable mechanical properties and lower curing temperature for facile processability. With 6 wt% incorporation, the peak heat release and total smoke production were reduced by 29.6% and 20.7%, respectively, and the time to ignition (TTI) increased as well as the fire growth rate (FIGRA) dropped off, which is of vital significance for saving lives in a fire. Meanwhile, the impact strength and flexural strength greatly enhanced by 72.9% and 22.0%, while its curing temperature was lower than that of controlled EP system. Interestingly, we also found that the solid carbon particles on the char surface apparently reduced from SEM image. The blending of its unique non-aromatic hyperbranched structure containing Si, P, N with epoxy architecture was responsible for the desirable integrated enhancement. The broad possibilities in the field of flame-retardant plastic with reduced fire hazards and excellent integrated performance enable the novel hyperbranched flame retardant a bright future for application.

Influence of β-FeOOH nanorods and ammonium polyphosphate on reducing the fire hazard of epoxy resins composites

β-FeOOH nanorods were synthesized and introduced into ammonium polyphosphate (APP) and epoxy resins (EP) composites, with subsequent investigation into improving the fire safety of epoxy resins (EP) composites. The limited oxygen index, UL-94 test and cone calorimeter test were adopted to investigate the flame retardant properties of the composites, and thermogravimetric analysis was used to study the thermal performance of the composites. The cone calorimetry results revealed that synergistic effects between β-FeOOH nanorods and APP can lead to not only the reduction of peak heat release rate compared with those of EP (85.6% reduction), but also the improvement on the smoke suppression performance such as CO, CO2 and SPR. Raman spectroscopy, FTIR and X-ray photoelectron spectroscopy of the char layers were adopted to investigate the flame retardant mechanism of the flame retardants composites. Generally, the reduced fire hazard of epoxy resins composites is due to synergistic effects between β-FeOOH nanorods and APP, which will provide stable char layers to trap the degrading polymer radicals.

Do fires discriminate? Socio-economic disadvantage, wildfire hazard exposure and the Australian 2019\u201320 \u2018Black Summer\u2019 fires

We examine the relationship between socio-economic disadvantage and exposure to environmental hazard with data from the catastrophic 2019–2020 Australian wildfires (Black Summer) that burnt at least 19 million hectares, thousands of buildings and was responsible for the deaths of 34 people and more than one billion animals. Combining data from the National Indicative Aggregated Fire Extent (NIAFE) and 2016 Socio-Economic Indexes for Areas (SEIFA), we estimate the correlation between wildfire hazard exposure and an index of community-level socio-economic disadvantage. Wildfire hazard exposure is measured as the interaction between the percentage of area burnt and proximity of the fire to settlements. The results reveal a significant positive relationship between fire hazard exposure and socio-economic disadvantage, such that the most socio-economically disadvantaged communities bore a disproportionately higher hazard exposure in the Black Summer than relatively advantaged communities. Our spatial analysis shows that the socio-economic disadvantage and wildfire hazard exposure relationship exists in inner regional, outer regional and remote areas of New South Wales and Victoria, the two worst-hit states of the Black Summer catastrophe. Our spatial analysis also finds that wildfire hazard exposure, even within a small geographical area, vary substantially depending on the socio-economic profiles of communities. A possible explanation for our findings is resource gaps for fire suppression and hazard reduction that favour communities with a greater level of socio-economic advantage.

Functionalization of PET with Phosphazene Grafted Graphene Oxide for Synthesis, Flammability, and Mechanism.

Significant improvement in the fire resistance of polyethylene terephthalate (PET) while ensuring its mechanical properties is a tremendous challenge. A novel flame retardant (GO-HCCP, graphene oxide-hexachlorocyclotriphosphazene) was synthesized by nucleophilic substitution of the graphene oxide (GO) and hexachlorocyclotriphosphazene (HCCP) and then applied in PET by an in situ polymerization technique. The scanning electron microscope (SEM) showed a better dispersion of GO-HCCP than GO in the PET matrix. The char yield at 700 °C increased by 32.5% with the addition of GO-HCCP. Moreover, the peak heat release rate (pHRR), peak smoke produce rate (pSPR)and carbon monoxide production (COP)values significantly decreased by 26.0%, 16.7% and 37.5%, respectively, which indicates the outstanding fire and smoke suppression of GO-HCCP. In addition, the composites exhibited higher elastic modulus and tensile strength without compromising the toughness of PET matrix. These significantly reduced fire hazards properties are mainly attributed to the catalytic carbonation of HCCP and the barrier effect of GO. Thus, PET composites with good flame-retardant and mechanical properties were prepared, which provides a new strategy for further flame retardant PET preparation.

Concurrent flame spread over vertically oriented paper sheet: The effect of sample thickness

SummaryPacking or printing paper made out of cellulose is widely produced and used in daily life. The thickness of thin material affects the burning process significantly. Concurrent flame spread is an effective approach when analyzing and evaluating the fire hazard for combustible materials. Conducting this work will provide further understanding of the flame spread mechanism and reduce fire hazard. It will also enable investigation of the effect of sample thickness on concurrent flame spreading over the thin paper sheets experimentally. Numerically examining concurrent flame spread over thin paper sheet with varied thicknesses is also performed using Direct Numerical Simulation, which can provide more details on flame spread process. Qualitatively, the model predictions agree reasonably with the experiment in terms of the flame contour, burn duration, and flame spread rate. The moving rates of the flame base and pyrolysis front decrease with sample thickness both experimentally and numerically. The relationship between net heat flux, flame standoff distance, and solid burning rate is analyzed, with the burning rate exhibiting a similar trend to that of the net heat flux. A correlation of the flame net heat flux with the normalized distance in the pyrolysis region is also established where the flame heat flux displays a decay trend with the normalized space.

Harmonized dataset of surface fuels under Alpine, temperate and Mediterranean conditions in Italy. A synthesis supporting fire management

Surface biomass characterization plays a key role in wildfire management. It allows classifying vegetation fuels flammability for fire risk analysis, to define silvicultural prescriptions for fire hazard reduction, to plan prescribed burning, or to model fire behavior and its effects, such as greenhouse gas and pollutant emissions. To facilitate fuel classification and analysis of potential fire behavior and effects in Italy, we harmonized 634 measurements of surface wildland fuels from Alpine, temperate and Mediterranean environments. The dataset provides quantitative data for duff, fine dead fuels and downed woody material, live grasses and shrubs fuel components. Surface fuel data were harmonized by subdividing loads (Mg ha-1) to standard size classes for dead (0-6, 6-25 and 25-75 mm) and live (0-6, 6-25 mm) fuels, collecting percent cover and depth/height (cm) of the various fuel components, and classifying observations into 19 fuelbed categories. To ensure comparability with existing vegetation classification systems, we classified each observation according to the European Fuel Map, the Corine Land Cover classes (level IV), the European Forest Types, and the forest categories of the Italian National Forest Inventory. The dataset and a photo description of each fuelbed category are available as Supplementary material. This dataset is the first step to develop several products at the national scale such as: (i) fuel type classification and mapping; (ii) carbon stock and wildfire emission estimates; (iii) calibration of fuel models for the simulation of fire behavior and effects.

Firefighting in Vulnerable Areas Based on the Connection between Fire Hydrants and Fire Brigade

A sufficient supply of water for firefighting is critical for effective responses to urban fires, thus reducing fire hazards. The aim of this study was the development of an analysis method for vulnerable areas with respect to firefighting activities that require the use of fire hydrants. In particular, a method was proposed for the determination of the operational range of firefighting activities based on the distribution of the fire hydrants and the roads that allow for the passage of firefighting vehicles. The proposed method, which employs a geographic information system (GIS), was applied to Buk-gu, Daegu City, South Korea. The research results revealed that the operational range of firefighting activities and vulnerable areas can be determined by studying the connection between the fire hydrant locations and the fire brigade in the analysis of the accessible areas. This study contributes to the development of GIS analysis methods for comprehensive vulnerability analyses of firefighting activities, including accessibility to fire hydrants.

Study on the Effect of Zinc on the Rheological, Mechanical and Thermal Properties and Fire Hazard of Unfilled and Filled CR/BR Vulcanizates.

This paper discusses the cross-linking and functional properties of elastomer composites containing chloroprene rubber (CR) and butadiene rubber (BR) cured in the presence of zinc (Zn) and reinforced with mineral fillers. The research aimed to evaluate the effectiveness of zinc as a new cross-linking substance with the simultaneous production of elastomer materials with good mechanical properties and a reduced fire hazard. The article concerns the study and explanation of the dependencies influencing the processing and functional properties of unfilled or filled elastomer blends containing different elastomers ratio or different zinc’s amount. The following fillers were used: silica, kaolin, chalk and montmorillonite. The results revealed that the cross-linking degree of CR/BR blends decreased with the increasing amount of butadiene rubber in the blends. The mechanical properties of the cured blends depended on the proportion of elastomers in the composites, the zinc amount, and the presence and type of filler. The flammability of CR/BR/Zn vulcanizates has been investigated before and after the filling. The parameters assessed by the oxygen index method and cone calorimetry, characterizing the behavior of the tested CR/BR/Zn vulcanizates under fire conditions, have shown that they constitute a low fire hazard and can be considered as non-flammable materials.

Functional covalent organic framework illuminate rapid and efficient capture of Cu (II) and reutilization to reduce fire hazards of epoxy resin

A key challenge for decontamination technologies is to study adsorbents possessing abundant approachable binding sites to realize rapid and effective capture of heavy metal ions in contaminated water. Herein, a three-dimensional porous covalent organic framework (COF) was synthesized, which can function as a scaffold for decorative binding sites. Considering the plentiful functional groups such as catechol groups of polydopamine (PDA), the decoration is demonstrated by coating PDA on the surface of COF via self-polymerization of dopamine under alkaline conditions. The obtained PDA-coated COF (COF@PDA) shows high affinity for copper ions (Cu (II)), while its adsorption capacity reaches 109.2 mg g−1 according to the Langmuir fitting. It takes only 10 min to achieve adsorption equilibrium and its equilibrium data follows pseudo-second-order kinetic model. Thermodynamic studies confirmed a spontaneous and exothermic removal process in essence. To achieve cyclic utilization of Cu (II), the adsorbed Cu (II) ions were heat-treated into CuO to obtain CuO-loaded COF@PDA (COF@PDA@CuO). It can serve as flame retardant for reducing fire hazards (heat, smoke and toxic gas) of epoxy resin (EP), thus confirming its dual functionalities towards environmental remediation and application as flame-retardant.

Functional covalent organic framework for exceptional Fe2+, Co2+ and Ni2+ removal: An upcycling strategy to achieve water decontamination and reutilization as smoke suppressant and flame retardant simultaneously

• The polydopamine-modified covalent organic framework (COF@PDA) was obtained. • Ultrafast and effective removal of Fe 2+ , Co 2+ and Ni 2+ for COF@PDA was identified. • The adsorbed Fe 2+ , Co 2+ and Ni 2+ was heat-treated to form its corresponding metal oxides. • The COF@PDA@Metal oxides were efficiently recycled to reduce the fire hazards of PS. A key challenge for wastewater remediation is to develop desirable adsorbents possessing abundant approachable binding sites to realize both ultra-fast capture and ultra-high absorbance for heavy metal ions. Herein, we illustrate how the three-dimensional porous covalent organic framework (COF) displays the right combination of properties, thus offering a platform for decorative chelating sites to address heavy-metal poisoning. The rational design is demonstrated by modifying polydopamine (PDA) on COF, which aims at anchoring plentiful functional groups, especially catechol groups to bind heavy metal ions. The obtained PDA-coated COF (COF@PDA) achieves rapid capture of Fe 2+ , Co 2+ and Ni 2+ , and reaches adsorption equilibrium within 10 s. According to the Langmuir fitting, the calculated capture capacities of COF@PDA for Fe 2+ , Co 2+ and Ni 2+ equal 204.9, 194.2, and 207.5 mg/g, respectively. Thermodynamic studies confirmed the spontaneous and exothermic characteristic of the adsorption process. Adhering to the concept of green chemistry and sustainable development, the good catalytic performance of transition metal ions intrigues us to further investigate its flame retardant application after recovering from sewage. The “recycling” strategy of adsorbed metal ions enables the reduction of fire hazards (heat, smoke and toxic gas) of polystyrene (PS) while retaining the mechanical properties of PS composites.

Multispectral satellite based monitoring of land cover change and associated fire reduction after large-scale peatland rewetting following the 2010 peat fires in Moscow Region (Russia)

Land cover changes following rewetting of 73 thousand hectares of peatland after the severe 2010 peat fires in Moscow Region (Russia) were monitored using multispectral remote sensing. The results revealed a reduction in the area of bare peat and dry grasslands, the rapid expansion of willow and birch vegetation, and a steady increase in wet grasslands and open water. Both the number and area of peat fires were clearly reduced compared to all wildfires in the region.Monitoring large areas over longer periods generally implies using different satellites and sensors. The developed methodology enabled assessing the effectiveness of rewetting to reduce fire hazard as well as identifying areas that remain fire-prone and require additional restoration effort. The methodology proved to be robust for the long-term monitoring of the effect of rewetting large areas of peatlands, as required under the Paris Agreement.

Self-heating ignition of open-circuit cylindrical Li-ion battery pile: Towards fire-safe storage and transport

Abstract The battery fire accidents frequently occur during the storage and transportation of massive Lithium-ion batteries, posing a severe threat to the energy-storage system and public safety. This work experimentally investigated the self-heating ignition of open-circuit 18650 cylindrical battery piles with the state of charge (SOC) from 30% to 100% and the cell number up to 19. As the ambient temperature increases, the self-heating ignition occurs and leads to a violent fire. The characteristic temperatures for both electrolyte leaking and thermal runaway decrease with SOC. The critical ambient temperature for self-heating ignition ranges from 135 °C to 192 °C, and it decreases with the increasing battery SOC, cell number, and pile size, which satisfies the self-ignition theory. The applied Frank-Kamenetskii analysis predicts the self-ignition ambient temperature could be lower to 30 °C for large battery piles with multiple tightly packed layers, such as those in the shipping container and warehouse. Nevertheless, creating gaps and providing effective cooling between each battery layer could effectively lower the fire risk by increasing the self-ignition ambient temperature above 125 °C. This work theoretically reveals the self-ignition characteristics of open-circuit battery piles, which could provide scientific guidelines to improve battery safety and reduce fire hazards during storage and transportation.