Fire Safety of Lithium-Ion Battery Warehouses – Challenges and Dilemmas

As well known, the increasing consumption of fossil fuel and the consequent environment problems, energy storage has become a global concern. The rechargeable batteries with high capacity, low cost and long cycling life is highly desired for large-scale applications in the future. 1 In the past decade, rechargeable lithium ion batteries (LIBs) have attracted considerable attention for their various advantages, such as high specific capacity, high voltage, long cycle life, and low self-discharge. These features make LIBs to be ideal power source for portable electronic devise and electric vehicles (EVs). 2Nevertheless, LIBs are encountering the next-level energy storage demand on further increase of energy density, operation safety and cycle life for EVs and smart grid energy technologies. 1 One hinder is the low specific capacity of the traditional graphite anode materials. Great efforts have been made to develop suitable anode materials with both high capacity and safety. Recently, transition metal sulfides have emerged as promising electrode materials for LIBs because of their high specific capacity, low cost, and other unique properties. Particularly, molybdenum disulfide (MoS2), a representative 2D material which delivers a similar structure to graphene, has been actively investigated owing to its high specific capacity (669 mAh g-1) from the four-electron transfer reaction, MoS2+4Li+4e→Mo+2Li2S. However, MoS2 still suffers from the inherent low electrical conductivity and large inherent volume change, which will result in poor cycling stability and rate property. 3 To address these drawbacks, one of the most effective strategies is to combine MoS2 with conductive carbon-based materials, such as porous carbon, carbon nanotubes and graphene. 4 Herein, the MoS2 nanosheets has been successfully grown on reduced graphene oxide (r-GO) aerogel with a one-pot hydrothermal method. The prepared MoS2 nanosheets show a strong interaction with the r-GO aerogel substrate which could provide strong combination and facile electron transport between the MoS2 and r-GO substrate. The unique structure of the composite which could remain the high capacity of the MoS2 and the high conductivity of the r-GO aerogel. This synergy effects makes the MoS2/r-GO composite exhibits excellent lithium storage performance with high capacity (950 mAh g-1 at 0.05 A g-1), good cyclic stability ( about 600 mAh g-1 at 200 cycles). Figure captions Figure 1. (a) Charge-discharge profiles of MoS2/r-GO composites. (b) Cycling performances at the current density of 0.05 A g-1 and 100 mA g-1. References Zhang, Z.; Zhao, H.; Teng, Y.; Chang, X.; Xia, Q.; Li, Z.; Fang, J.; Du, Z.; Świerczek, K., Carbon-Sheathed MoS2 Nanothorns Epitaxially Grown on CNTs: Electrochemical Application for Highly Stable and Ultrafast Lithium Storage. Advanced Energy Materials 2017, 8 (7), 1700174.Qin, W.; Li, Y.; Teng, Y.; Qin, T., Hydrogen bond-assisted synthesis of MoS2/reduced graphene oxide composite with excellent electrochemical performances for lithium and sodium storage. Journal of Colloid and Interface Science 2018, 512, 826-833.Zhang, X. Q.; Li, X. N.; Liang, J. W.; Zhu, Y. C.; Qian, Y. T., Synthesis of MoS2@C Nanotubes Via the Kirkendall Effect with Enhanced Electrochemical Performance for Lithium Ion and Sodium Ion Batteries. Small 2016, 12 (18), 2484-2491.Xia, S.; Wang, Y.; Liu, Y.; Wu, C.; Wu, M.; Zhang, H., Ultrathin MoS2 nanosheets tightly anchoring onto nitrogen-doped graphene for enhanced lithium storage properties. Chemical Engineering Journal 2018, 332, 431-439. Figure 1

Aim: The purpose of this article is to highlight the issue of fire protection in garages, with particular emphasis on facilities where charging points for electric and plug-in hybrid cars are to be installed. Introduction: The development of electromobility poses new challenges for fire protection in terms of properly securing garages in buildings and ensuring appropriate conditions for rescue operations. Fires involving electric vehicles, especially those with lithium-ion traction batteries, are characterized by high dynamics, long duration, the risk of rapid spread, the release of large amounts of smoke, as well as toxic and corrosive chemicals. Giving particular consideration to these hazards is especially important in enclosed garages, where difficulties in accessing the fire source and removing toxic combustion products are to be expected. The challenge lies in selecting the right active and passive fire protection measures for garages, as well as electrical protection for charging points for electric and plug-in hybrid cars. Methodology: As part of the work on the article, literature on the subject was reviewed and analysed, along with the current legal status regarding the installation of charging points at parking spaces, as well as applicable regulations and technical knowledge in the field of fire protection in garages. Conclusions: The above content provides a concise overview of the current state of knowledge regarding the fire hazard posed by electric cars. The article discusses the applicable regulations and technical principles of fire protection in garages. Solutions for fire protection in buildings where electric or plug-in hybrid vehicles are expected to be charged should include safety measures appropriate to the associated fire risk. Among the most important safeguards for controlling this hazard are early fire detection, which allows firefighting measures to be taken in the initial stages, and the use of solutions that limit the spread of fire until rescue teams arrive at the scene.

As global climate change intensifies, extreme catastrophic weather. As a result, the vulnerability of power infrastructure gradually worsens, leading to an increased threat of power supply disruption. In order to cope with the threat of possible power supply disruption and to accommodate more residents in the event of a disaster, backup power generation and storage facilities are necessary should establish in residential and commercial areas. This study establishes a software analysis model of power demand resilience in the residential area, analyzes various power demand resilience scenarios, and discusses the operation of reasonable backup power generation and energy storage facilities, and power load management and control strategies. In the future, these software tools will be used to analyze the rational allocation and operation strategies of disaster prevention at power facilities in similar situations. This study takes the Fengshan Smart Green Community as the reference field, and extends the simulated facilities as the area of power demand resilience analysis, in an integrated residential area and a commercial area. This study has completed four case studies, including: (1) baseline scenario, (2) “use of diesel generators” scenario, (3) “expanding lithium battery capacity” scenario, and (4) “expanding lithium battery capacity and controlling lithium battery power output in the integrated residential area” scenario. The conclusions of this study include: (1) To cope with the intensified global climate change, adequate deployment of various backup power generation and storage facilities to enhance power resilience can effectively mitigate the threat of power supply disruption. (2) According to the case study results, there is sufficient solar photovoltaic in the residential area of Fengshan Smart Green Community. However, the energy storage and power supply capacity of lithium batteries are insufficient, and it is challenging to perform the backup power function. (3) To supply electricity to the power management system and the medical and shelter area adequately, this study suggests Fengshan Smart Green Community strengthens the power storage and power supply capacity of lithium batteries. (4) Solar photovoltaics are zero-carbon power; it can be a priority backup for power demand resilience. However, solar power is not available when there is insufficient sunshine. (5) The use of a diesel generator can flexibly assist the solar photovoltaic and lithium batteries to ensure the adequate power supply. (6) The use of diesel generators for power generation during a time of crisis is not pollution-free. However, their use for management in a crisis or disaster situation is in order when other power supply backups are insufficient or have failed. The critical findings include: (1) Solar photovoltaics are zero-carbon power; it can be a priority backup for power demand resilience. However, solar power is not available when there is insufficient sunshine. (2) The use of diesel generators for power generation during a time of crisis is not pollution-free. However, their use for management in a crisis or disaster situation is in order when other power supply backups are insufficient or have failed.

Effect of ambient pressure on the fire characteristics of lithium-ion battery energy storage container

The growing need for large lithium batteries and lithium battery powered equipment aboard submarines provides major challenges to the US Navy; two of these challenges include (1) early battery casualty detection and (2) containment or mitigation of hazards associated from lithium-based battery casualties. Lithium ion rechargeable batteries used within research unmanned undersea vehicles (UUV) was abusively tested inside of its vehicle and was instrumented with water mitigation and various types of presumptive pre/post casualty onset detection sensors. These efforts were conducted under the requirements for the Navy’s Lithium Battery Safety Program, Naval Sea Systems Command Instruction 9310.1C and related documents as guidance for need. This effort followed similar recent works for the storage and carriage of large form lithium and lithium-ion batteries conducted preciously. This paper will review the results of these tests conducted by the Naval Surface Warfare Center, Carderock Division (NSWCCD), Naval Undersea Warfare Center, Newport (NUWC NWPT) and the Naval Research Center (NRL) over the past six years. These efforts have enabled the carriage and deployment of lithium battery powered systems from surface platforms and are expected to enable the deployment from undersea platforms.

This article presents research on developing a synthetic measure to assess the readiness of individual EU countries to store energy from renewable energy sources. The authors developed individual measures that describe both the technical aspects of energy storage and the systemic and strategic aspects related to energy security and energy transition. These measures enabled the development of a synthetic measure, the Energy Storage Readiness Index (ESRI-BESS), and scenarios for the development of energy storage facilities in the European Union. TOPSIS and Monte Carlo methods were used. In the research presented, the authors focused their analyses on how the system interacts with storage facilities, rather than on what is installed. A quantitative set of indicators was constructed, embedded in the 4A energy security model. The resulting indicator measures not only whether storage facilities exist but also whether the system is prepared to ensure the country’s energy security. The results obtained indicate the need to build a flexible regulatory framework adapted to the growing role of storage facilities, that is, to facilitate and accelerate the process of connecting storage facilities to the grid. In the context of 4A, it is important to note that energy storage facilities can strengthen all four pillars of energy security when infrastructure development is paralleled by reforms and grid integration. The ability to store and flexibly manage energy is becoming a new dimension of energy transformation.

The rising energy demands have prompted the development of various advanced technologies, with Lithium-ion technology emerging as a leading and efficient energy source. However, this technology poses significant hazards to human health and safety. Recently, incidents involving Lithium-ion batteries have surged due to multiple factors and failure modes, with thermal runaway being a major contributor to these accidents. To address these concerns, innovative technologies and strategies in fire safety and Lithium-ion battery safety are being implemented to mitigate the occurrence of thermal runaway and battery-related incidents. KEY WORDS: Lithium-Ion, Thermal Runaway, Fire Safety, Electrical Safety

SummaryInnovation in clean-energy technologies is central toward a net-zero energy system. One key determinant of technological innovation is the integration of external knowledge, i.e., knowledge spillovers. However, extant work does not explain how individual spillovers come about: the mechanisms and enablers of these spillovers. We ask how knowledge from other technologies, sectors, or scientific disciplines is integrated into the innovation process in an important technology for a net-zero future: lithium-ion batteries (LIBs), based on a qualitative case study using extant literature and an elite interview campaign with key inventors in the LIB field and R&D/industry experts. We identify the breakthrough innovations in LIBs, discuss the extent to which breakthrough innovations—plus a few others—have resulted from spillovers, and identify different mechanisms and enablers underlying these spillovers, which can be leveraged by policymakers and R&D managers who are interested in facilitating spillovers in LIBs and other clean-energy technologies.

Saft lithium-ion energy and power storage technology

Last developments in polymers for wearable energy storage devices

Wind, as well as photovoltaic (PV), is widely used. Like loads, its power cannot be predicted, which results in the grid having to bear the power imbalance between wind-PV and loads, and substantial power fluctuations are not tolerated. Hybrid energy storage systems (HESS) containing multiple storage methods are considered effective solutions. In this paper, pumped storage and lithium-ion battery storage are fully considered, as they are supposed to have excellent performance and are highly complementary. We categorize the power imbalance into low, medium, and high according to the magnitude of the power imbalance. When the power fluctuation is low, the battery dominates. In contrast, the pumped storage dominates when the power fluctuation is high. Most importantly, when the power fluctuation is medium, we utilize an optimized first-order low-pass filter to allocate the power between the pumped storage and the lithium-ion battery. We change the filtering time in real-time according to the battery’s state of charge (SOC) to reasonably allocate the power between the pumped storage and the lithium-ion battery and ensure the SOC fluctuates within a reasonable range. This paper confirms the feasibility of the proposed strategy, where the pumped storage power fluctuates very little, in contrast, the battery power fluctuates significantly, and the SOC is always within the set reasonable range. Most importantly, the strategy proposed in this paper is straightforward to implement, which is crucial for engineering applications.

Global demand for lithium-ion secondary batteries have been increasing due to new market growth from electric vehicles and power storage systems. Lithium-ion batteries possess high power density, energy density and long cycle life without memory effect and little self-discharge, and have been primary energy storage system for commercial electronics. However, recent accidents regarding battery safety, such as Samsung Note 7 issue, has raised doubt among public about lithium-ion batteries as option for energy storage. Separator is one of the primary component for lithium-ion battery safety. Commercial separators like PE or PP not only possess outstanding mechanical and electrochemical performance, but also have thermal shutdown function that provide safety measure by pore—blocking with melted polyolefin materials. Nevertheless, polyolefin materials suffered serious shrinkage at elevated temperature, which cause internal short-circuited of batteries ; also, polyolefin materials have relatively low electrolyte uptake, and could be major obstacle for future lithium-ion battery application. Hence it’s necessary to design new type of separator that guarantee battery safety and demonstrate better electrochemical performance In this study, we proposed a brand-new method to design composite separator with high thermal stability, electrolyte uptake ability and thermal shutdown function. Polyimide(PI) nanofiber film was used as substrate and produced by electrospinning technique, and ultra-thin Low-Density-Polyethylene(LDPE) layer was laid upon PI by simple spin-coating method. Spin-coating method provided unique advantages such as ultra thin coating layer (less than 1 micron), uniform coating structure and simple process, and was yet been applied for construction of composite film as lithium-ion battery separator. Coating parameter was tuned to obtain the optimized composite separator. Field-emission scanning electron microscope (FE-SEM) was used to investigate morphologies of separators ; Contact angle measurement was conducted to verify electrolyte affinity of different separators ; A.C. impedance method was used to measure conductivities and verify thermal shutdown of separators, and electrolyte uptake of different separators were measured by electrolyte soaking method in an argon-filled glovebox. The composite film had sub-micron average pore size, and possessed excellent physical properties, for instance, high porosity(73%), electrolyte uptake(1300%), ion conductivity(4.3*10-4 S/cm), air permeability(gurley value=0), and thermal stability(no shrink up to 150。C). Thermal shutdown function of composite film was also confirmed by impedance measurement at elevated temperature. It was noticed that physical properties between pristine PI and composite film were similar owning to ultra-thin coating layer, which mitigate performance loss from LDPE coating. Afterward, full cell battery tests were conducted with CR2032 type coin cell (Cathode : LFP, anode : MCMB, electrolyte : 1 M LiPF6 in EC/EMC/DMC=1:1:1+1%VC, 1C=2.4mAh/g). The first cycle charge-discharge curves, rate capability and cyclic performance were conducted. The composite film showed flatter first cycle charge-discharge plateau, better capacity retention at higher C-rate (Composite film :102 mAh/g at 1C, 79% retention, Celgard 2500 : 73 mAh/g, 51% retention , w.r.t. 0.1C), and higher discharge capacity at 0.5C 50th cyclic test. The higher porosity and electrolyte uptake of composite film facilitated ion conduction and were the main cause for enhanced battery performance. With enhanced thermal stability and electrochemical performance, we expected this type of composite separator to be promising for future lithium-ion battery application. Figure 1

Lithium-ion battery energy storage system is of positive significance for improving the flexibility of the power system with a high proportion of new energy integration. Along with their high energy or power densities, portability, and promising life cycle, lithium-ion batteries have a large advantage in the application of energy storage systems. However, the lithiumion battery characteristics are appreciably affected by temperature. In the low-temperature environment, there is a deterioration of power characteristics, the life-cycle, as well as the available capacity in energy storage, which is not conducive to the development of energy storage. In this paper, the lithium-ion temperature-dependent battery model with its control strategy is constructed, and the discharge characteristics of the battery are simulated at different temperatures. Then, the heating model is proposed to alleviate the performance degradation of lithium-ion batteries at low temperatures. Finally, from the economic point of view, the optimal preheating target temperature is obtained considering the energy consumed by the preheating system and the increased discharge energy after preheating.

Lithium-ion battery will emit gas-liquid escapes from the safety valve when it gets in an accident. The escapes contains a large amount of visible white vaporized electrolyte and some colorless gas. Effective identification of the white vaporized electrolyte and an early warning can greatly reduce the risk of fire, even an explosion in the energy storage power stations. In this paper, an early warning method of lithium-ion battery fire is proposed, which is based on gas-liquid escape image recognition. Firstly, an image recogonition algorithm based on the YOLOv3 is proposed. The original Darknet53 feature extraction network in the algorithm is replaced with a lightweight ReXNet feature extraction network, considering the safety requirements of fast and accurate identification of the storage. In addition, the K-means clustering algorithm is used to obtain appropriate initialized anchor boxes to speed up the convergence of the model. Finally, the multi-scale feature fusion is combined with the path aggregation network to improve the detection accuracy of the model, so that the model can achieve good recognition of both large and small targets. The results show that the method shows a good effect in identifying the vaporized electrolyte of the actual lithium-ion battery storage. The model prediction speed tested on the GTX1650 graphics card can reach 65 frames per second, and the average accuracy is 84.35%. It basically meets the needs of practical applications. The research in this paper can further improve the safety of lithium-ion battery energy storage power stations and promote the healthy development of electrochemical energy storage.

A Microgrid consists renewable energy generators (REGs) along with energy storage in order to fulfill the load demand, even when the REGs are not available. The battery storage can meet the load demand reliably due to its fast response. The available technologies for the battery energy storage are lead-acid (LA) and lithium-ion (LI). The specific energy density of LI is higher than the LA battery and it has fast charge and discharge rate as compared to LA. However, a proper comparison of the performances of these two storage systems should be done in order to establish quantitatively the advantages either technology offers for a given application. In this study, a feasibility and comparative performance analysis of LA and LI based energy storage systems for grid-connected microgrid is carried out using NREL, SAM simulation tool. Grid-connected microgrid consists the solar photovoltaic (SPV) as the primary power generator. The excess energy produced by SPV is stored in the batteries. If there is excess PV electricity after charging batteries to maximum state of charge then excess electricity can be fed to the mains-grid. If both PV and battery powers are not sufficient to fulfill the demand then the deficit power can be taken from the grid. It is found that for a typical load the power fed to grid is more with LI based system as compared to the LA based system. The power imported from the grid is lesser with LI battery storage in comparison with LA storage. The results provide the feasibility and economic benefits of LI battery over the LA battery. The levelized cost of electricity are found to be ₹ 10.6 and ₹ 6.75 for LA and LI batteries respectively for energy storage application in the microgrid.