储能锂电池模组温度场数值计算与散热系统优化设计

储能电池热失控是引发储能电站事故的主要因素之一,储能电池的热管理对电池使用效率、寿命以及运行安全具有重要意义。本文设计了以60系列大圆柱电池单体为基本单元、额定电量为11.52 kWh的储能电池模组,基于有限元方法建立了电池模组热流耦合数值计算模型,分析电池模组内部风道空气流速以及电池组温度场分布规律,并开展储能电池模组原型充放电温升试验,验证数值计算结果的准确性。进一步优化储能电池模组的温度场分布,通过调整散热孔排布方式对电池模组进行了优化设计,提出一种侧面U形开孔结构,储能电池模组的温度一致性和电芯最大温度得到了显著改善。优化后,模组电芯最大温差降低2.6℃,温度标准偏差降低1.18,研究结论可为储能电池模组温升计算与散热设计提供参考。     

锂电池储能电站防消一体化系统设计及控制策略

面向锂电池储能电站的安全需求,遵循“预防为主、防消结合”的原则,设计锂电池储能电站防消一体化系统,实现数据融合和智能诊断,建立早期预警、后期灭火防护的完整系统;参照实际储能预制舱结构,搭建储能预制舱试验环境,开展锂电池单体及模组热失控及灭火试验,结果表明：防消一体化系统控制策略通过安全预警、防护、消防系统的分级工作,实现了火灾早期预警以及后期灭火防护,最大程度降低了电池热失控带来的危害;以细水雾作为灭火介质能在短时间内熄灭磷酸铁锂电池火灾,并能有效防止电池复燃。     

含电池储能系统的电热联合系统风电接纳能力评估

为促进风电消纳,减少“弃风”,将电池储能系统（BESS）接入电热联合系统。为考虑风功率的不确定性,基于风功率预测误差的概率特性建立风功率场景概率模型。然后,建立包含BESS的电热联合系统风电接纳能力评估模型。模型具有系统运行成本最低和“弃风”电量最小2个不同维度优化目标,且目标优化之间可能存在冲突。为求解该模型,基于改进主要目标法将其转换为多个单目标优化问题,并采用GAMS中DICOPT求解器给出风电接纳能力评估模型的帕累托解集。基于帕累托解集,从接纳电量和接纳成本两方面对BESS接入后的电热联合系统风电接纳能力进行深入分析。最后进行仿真分析,验证了该文所提模型及求解算法的有效性。     

计及弃风的“电气互补-冷热联供”模式研究

针对弃风严重以及传统供暖方式存在难以“热电解耦”的问题,提出一种将蓄热式电锅炉、燃气锅炉、吸收式制冷机相结合的“电气互补-冷热联供”弃风消纳模式。首先,根据弃风和冷热负荷特性建立“电气互补-冷热联供”模型;然后,考虑供暖与制冷成本,构建“电气互补-冷热联供”经济性模型;最后,通过算例分析与传统“燃气锅炉-空调”供暖制冷模型的经济性进行对比。结果表明：所提模式可在消纳弃风的同时减少碳排放量,达到提升系统收益的目的。     

Research progress in the consistency screening of Li-ion batteries

锂离子电池因综合性能优良,近年来在移动储能和固定储能领域的应用发展迅速。当多个单体电池通过串并联组成电池模组时,不仅电池组的能量低于电池单体能量的加和,电池组的寿命也明显低于单体电池的水平。除了电池运行环境不均匀（如温度场）外,电池组内部电池单体之间微小的不一致性也是造成电池组性能快速衰减的主要原因。依据电池组的结构建立电池一致性的筛选方法和标准,是目前锂离子电池模组研究中亟待解决的关键技术。本文回顾了近年来国内外锂离子电池一致性筛选方法研究领域的进展,对锂离子电池一致性的内涵进行了剖析,并重点对串联筛选方法进行了评述。     

Reviews of selected 100 recent papers for lithium batteries （Dec. 1,2014 to Jan. 31,2015）

该文是一篇近两个月的锂电池文献评述,我们以“lithium”和“batter*”为关键词检索了Web of Science从2014年12月1日至2015年1月31日上线的锂电池研究论文,共1890篇,选择其中100篇加以评论。正极材料主要研究了富锂相材料的结构演变及表面包覆对层状和尖晶石材料循环寿命的影响。高容量的硅、锡基负极材料研究侧重于纳米材料、复合材料、黏结剂及反应机理研究,电解液添加剂、固态电解质、锂空电池、锂硫电池的论文也有多篇。理论模拟工作包括材料体相、界面结构和输运性质,除了以材料为主的研究之外,针对电池的原位分析、电池模型的研究论文也有多篇。     

Reviews of selected 100 recent papers for lithium batteries （April 1,2015 to May 31,2015）

该文是一篇近两个月的锂电池文献评述,我们以“lithium”和“batter*”为关键词检索了Web of Science从2015年4月1日至2015年5月31日上线的锂电池研究论文,共有1416篇,选择其中100篇加以评论。正极材料主要研究了富锂相材料、三元材料和尖晶石材料的结构演变及掺杂和表面包覆对其循环寿命的影响。高容量的硅基负极材料研究侧重于纳米材料、复合材料、黏结剂及反应机理研究,电解液添加剂、固态电解质、锂硫电池的论文也有多篇。理论模拟工作包括电极材料体相和界面结构以及电解质的输运性质,除了以材料为主的研究之外,电池模型和针对电池的失效分析、热安全分析的研究论文也有多篇。     

考虑复合储能电站接入的电网日前-日内两阶段滚动优化调度

为提高电力系统对光伏的接纳能力,降低光伏波动对电力系统运行的影响,提出一种考虑电池储能-抽水蓄能复合储能的电力系统日前-日内两阶段“源-储-荷”协调优化调度策略。首先,在日前调度模型中,以最小化系统总运行经济成本为目标,综合复合储能资源和负荷侧各类需求响应资源对电网进行双端协调优化。然后,在日内短时间尺度上,供需双端协调优化机组出力与需求侧响应,充分发挥抽水蓄能的调峰能力以及电池储能对光伏波动的抑制作用。所提模型通过CPLEX软件求解,算例结果验证了该模型能协调优化系统内各类可调节资源,有效降低系统弃光率。     

车用电池模组热蔓延防护结构的数值仿真研究

本文通过数值仿真研究了一种抑制方形电池模组热失控蔓延的防护结构.针对车用50 A·h方形三元锂离子电池,基于锂离子电池电极材料与电解液副反应机理建立单体电池热失控模型.通过与已有研究结果进行对比验证,表明所建立的热失控模型具有较高的精度.基于验证后的单体电池热失控模型,建立了加装导热套筒的电池模组热防护结构.导热套筒底...     

面向碳中和目标的小型车载动力电池可持续发展研究

当前我国各行业均关注“碳中和”目标,电动汽车作为新能源材料和器件在交通行业实现节能环保目标的代表性载体之一,对我国实现碳中和目标有着重要意义。动力电池是电动汽车的重要组成部分,迫切需要解释其“碳中和”特性。将锂离子电池组在生产阶段的各类环境影响作为研究对象,采用生命周期评价方法,分析生产锂离子电池的过程中,成分组成对环境的综合影响。结果表明,硫化铁固态电池组（FeS₂SS）在足迹家族、资源耗竭和毒性损害的11类三级指标中环境潜值都较小,说明FeS₂SS电池组在生产阶段产生的综合环境影响较小,而磷酸铁锂-石墨电池（LFPy-C）、三元锂-硅纳米管电池（NMC-SiNT）、三元锂-硅纳米线电池（NMC-SiNW）在各项环境影响值中贡献程度均较高。为实现碳中和目标,减少碳排放,NMC-SiNW、LFPy-C、NMC-C三种电池组的生产应进行优化。     

动力电池支撑架结构设计及散热性能分析

可再生能源的发展势必带动动力电池的发展,在促进退役动力电池循环利用方面也将取得较大成效,在动力电池发展过程中,其安全性是值得广泛关注的重点问题,为提高动力锂电池组放电时散热效率,设计电池组支撑架,采用计算机仿真的方法研究不同支撑架结构、不同工质、不同流速下18650型锂电池构成的动力电池组的热性能。通过对空气和水2种工质流体、工质流速大小、工质入口位置等参数进行组合仿真分析,结果表明,随着工质流速的增加,电池组及支撑架表面的最高温度逐渐降低,当工质流速大于10 m/s时趋于稳定;适当的工质流入口的位置可增强降温效果,在低流速状态下,空气和水分别作为冷却工质时,纵向包裹型电池支撑架比横向包裹型电池支撑架电池组中表面温度分别降低了2.64%和1.86%;在高流速状态下,空气和水分别作为冷却工质时,纵向包裹型电池支撑架比横向包裹型电池支撑架电池组中表面温度分别降低了3.15%和1.83%。动力电池支撑架结构设计可为后续电池热控制提供理论参考。     

Experimental investigation on thermal performance of silica cooling plate‐aluminate thermal plate‐coupled forced convection‐based pouch battery thermal management system

The power battery as an indispensable part of electric vehicle has attracted much attention in recent years. Among these, the lithium‐ion battery is the most important option due to the high energy density, good stability, and low discharge rate. However, the thermal safety problem of lithium‐ion battery cannot be ignored. Therefore, it is very necessary to explore an effective thermal management system for battery module. Here, a thermal silica cooling plate‐aluminate thermal plate (SCP‐ATP) coupling with forced convection air cooling system as a thermal management system is proposed for improving the cooling performance of pouch battery module. The results reveal that the heat dissipating performance and temperature uniformity of pouch battery module with SCP‐ATP are greatly improved compared with other thermal management systems. Moreover, the highest temperature can be controlled below 50°C, and the temperature differences can be maintained with 3°C when the SCP‐ATP coupling forced convection is utilized to enhance the heat transfer coefficient. Furthermore, considering the cooling effectiveness and consumption cost comprehensively, the optimal air velocity of the SCP‐ATP coupling forced convection cooling system is 9 m/s. In addition, the SCP‐ATP filling with different proportions of acetone has also been investigated for pouch battery module, indicating that 50% acetone exhibited a better heat transfer effect than the 30% one. Therefore, this research would provide a significant value in the design and optimization of thermal management systems for battery module.     

动力汽车用锂电池热管理系统仿真分析

为了研究动力汽车用锂电池温度场分布,建立了单体电池及电池组仿真模型,通过实验与FLUENT软件模拟验证的方式分析单体电池温度场。通过仿真分析讨论电池组温度场,采用三种不同的进出风方式进行空气强制冷却电池组,分析了进出风口有倾角与无倾角的不同温度控制效果,结果表明带有倾角的进出风方式有利于降低电池组最高温度。采用电池组壳体侧面开孔方式进行电池组热管理,可有效改善电池组放电过程的温度分布均匀性。     

Research on heat dissipation performance and flow characteristics of air‐cooled battery pack

With the depletion of fossil fuels and the aggravation of environmental pollution, the research and development speed of electric vehicles has been accelerating, and the thermal management of battery pack has become increasingly important. This paper selects the electric vehicle battery pack with natural air cooling as the study subject, conducts simulation analysis of the heat dissipation performance of battery packs with and without vents. Then this paper researches on the influence of internal flow field and external flow field. Field synergy principle is used to analyze the effect of velocity field and temperature field amplitude. The results show the following: it is found that the maximum temperature rise and the internal maximum temperature difference of the battery pack with vents are reduced by about 23.1% and 19.9%, raising speed value can improve the heat dissipation performance, and raising temperature value can decrease the heat dissipation performance. Reasonable design of the vents can make the inner and outer flow field work synergistically to achieve the best cooling effect. Then the reference basis for the air cooling heat dissipation performance analysis of electric vehicle, battery pack structure arrangement, and air‐inlet and air‐outlet pattern choosing are offered.     

3D electro‐thermal modelling and experimental validation of lithium polymer‐based batteries for automotive applications

This article presents an electro‐thermal model of a stack of three lithium ion batteries for automotive applications. This tool can help to predict thermal behaviour of battery cells inside a stack. The open source software OpenFOAM provides the possibility to add heat generation because of Joule losses in a CFD model. Heat sources are introduced at the connectors and are calculated as a function of battery discharge current and internal resistance. The internal resistance is described in function of temperature. Simulation results are validated against experimental results with regard to cooling air flow field characteristic and thermal behaviour of the cell surface. The validation shows that the simulation is capable to anticipate air flow field characteristics inside the battery box. It also predicts correctly the thermal behaviour of the battery cells for various discharge rates and different cooling system conditions. The simulation supports the observation that batteries have a higher temperature close to the connectors and that the temperature increase depends highly on discharge rate and cooling system conditions. Copyright © 2016 John Wiley & Sons, Ltd.     

Experimental examination of large capacity liFePO4 battery pack at high temperature and rapid discharge using novel liquid cooling strategy

To overcome the significant amounts of heat generated by large‐capacity battery modules under high‐temperature and rapid‐discharge conditions, a new liquid cooling strategy based on thermal silica plates was designed and developed. The superior thermal conductivity of the thermal silica plate combined with the excellent cooling effect of water led to a feasible and effective composite liquid cooling system during long cycle testing. The experimental results showed that the addition of thermal silica plates can greatly improve the cooling capacity that can allow the maximum temperature difference to be controlled at 6.1°C and reduce the maximum temperature of the battery module by 11.3°C, but still outside the optimum operating temperature range. The water flow significantly enhanced the cooling performance/stability, and slight temperature fluctuations were observed during cycling. The cooling performance obviously improved as the flow rate rose. When the velocity reached a critical value, further increase in water flow rate induced a slight influence on the cooling capacity due to the limitation of the materials. The maximum temperature (T_max ) could be reduced to 48.7°C, and temperature difference (?T ) could be maintained within 5°C when the water flow velocity increased to 4 mL/s, which was determined as the best value. The energy consumed by the water pump is only 1.37% of the total energy of the battery module. Overall, these findings should provide novel strategies for the design and optimization of battery thermal management system.     

Lithium battery thermal management system for hybrid vehicles

为研究动力电池组的温度特性以及维持其工作在最佳的温度范围内,以锂离子电池为研究对象,设计了一种新型混合动力汽车的电池热管理系统,利用空调系统和发动机排气系统来调控电池组的温度。建立了锂电池组的三维瞬态产热数值模型,以电池组的三维尺寸和进风口流速为输入参数,以降低电池组的最大温升和提高电池组的温度均匀性为输出参数,利用FLUENT仿真软件和DesignXplorer模块进行联合优化设计了电池组的结构。优化后的电池组的温升比优化前降低了5.39 K,电池组温差降低了6.41 K。分析了恒倍率放电以及对流换热系数对单体电池温升的影响,研究表明：放电倍率越大电池温升越快,放电结束后电池的温度越高,在对流换热系数小于30 W/（m²·K）时,散热效果明显。对电池组在不同条件下加热或者冷却进行了仿真分析,验证了该电池热管理系统的可行性。     

An experimental investigation of liquid cooling scheduling for a battery module

The thermal safety of electric vehicle battery modules attracts public concern; controlling the severe temperature rise and ensuring uniform temperature distribution are essential to addressing this problem. In this research, a liquid cooling-based cooling structure equipped with minichannels is proposed to prevent a battery module's overheating. A novel cooling scheduling study is proposed to arrange the coolant flow rates at different cooling stages. The temperature rise, temperature difference, and energy consumption of all the cooling schedules are measured in experiments. Experimental findings indicate that appropriate cooling scheduling achieves the thermal objectives and reduces energy consumption through scheduling the coolant flow rate in the cooling process. A comprehensive cooling schedule selection is carried out to select the optimal cooling schedule with the highest cooling efficiency through evaluating both the thermal and energy consumption objective parameters under different discharging current rates (0.5C, 1C, and 1.5C). The optimal cooling schedule maintains the maximum temperature of the battery module within 26°C, 32°C, and 40°C under 0.5C, 1C, and 1.5C discharging current rates, respectively. Moreover, the temperature SD and the energy consumption of the liquid cooling-based battery pack can be controlled within 3.5°C and 40 J, respectively.     

The forced air cooling heat dissipation performance of different battery pack bottom duct

Due to the requirement of the battery for the thermal management system, based on the coupling relationship between the velocity field and the thermal flow field of the field synergy principle, the flow paths of the forced air cooling system for different battery packs were analyzed. First, the thermodynamic parameters of the battery were collected through experiments and verified by simulation. Secondly, based on the collected thermodynamic parameters of the battery, the heat generation model of the battery, the heat conduction model of the gas, and the coupled heat dissipation model of the battery and air were established. Determine the boundary conditions, calculation methods and evaluation indicators required for simulation; Finally, based on four different driving conditions, the forced air cooling performance of the double “U” shape duct and double “1” type duct is simulated. Through the analysis of the results, the dual “U” air ducts have a more heat dissipation effect on the battery pack than the double “1” shape duct. The results conform to the definition of the field synergy principle for the coupling relationship between the velocity field and the heat flow field. Then research provide references for the design of battery packs and matching of cooling systems.     

Effects of reciprocating liquid flow battery thermal management system on thermal characteristics and uniformity of large lithium-ion battery pack

To investigate the thermal characteristics and uniformity of a lithium-ion battery (LIB) pack, a second-order Thevenin circuit model of single LIB was modeled and validated experimentally. A battery thermal management system (BTMS) with reciprocating liquid flow was established based on the validated equivalent circuit model. The effects of the reciprocation period, battery module coolant flow rate and ambient temperature on the temperature and the temperature imbalance of batteries were studied. The results illustrate that the temperature difference can be effectively reduced by 3°C when the reciprocating period is 590 seconds. The reciprocating coolant flow rate is 11.5% and 33.3% that of the unidirectional flow BTMS for cooling and heating when same thermal effects are to be achieved. Under the same ambient temperature condition, the maximum temperature and average temperature difference can be reduced by 1.67°C and 3.77°C, respectively, at best for the battery module investigated with a reciprocating liquid-flow cooling system. The average temperature difference and heating power consumption could be reduced by 1.2°C and 14 kJ for reciprocating liquid flow heating system with period of 295 seconds when compared with unidirectional flow. As a result, the thermal characteristics and temperature uniformity can be effectively improved, and the parasitic power consumption can be significantly reduced through adoption of a reciprocating liquid flow BTMS.