Internal short circuit and accelerated rate calorimetry tests of lithium-ion cells: Considerations for methane-air intrinsic safety and explosion proof/flameproof protection methods

Researchers with the National Institute for Occupational Safety and Health (NIOSH) studied the potential for lithium-ion cell thermal runaway from an internal short circuit in equipment for use in underground coal mines. In this third phase of the study, researchers compared plastic wedge crush-induced internal short circuit tests of selected lithium-ion cells within methane (CH₄)-air mixtures with accelerated rate calorimetry tests of similar cells. Plastic wedge crush test results with metal oxide lithium-ion cells extracted from intrinsically safe evaluated equipment were mixed, with one cell model igniting the chamber atmosphere while another cell model did not. The two cells models exhibited different internal short circuit behaviors. A lithium iron phosphate (LiFePO₄) cell model was tolerant to crush-induced internal short circuits within CH₄-air, tested under manufacturer recommended charging conditions. Accelerating rate calorimetry tests with similar cells within a nitrogen purged 353-mL chamber produced ignitions that exceeded explosion proof and flameproof enclosure minimum internal pressure design criteria. Ignition pressures within a 20-L chamber with 6.5% CH₄-air were relatively low, with much larger head space volume and less adiabatic test conditions. The literature indicates that sizeable lithium thionyl chloride (LiSOCl₂) primary (non rechargeable) cell ignitions can be especially violent and toxic. Because ignition of an explosive atmosphere is expected within explosion proof or flameproof enclosures, there is a need to consider the potential for an internal explosive atmosphere ignition in combination with a lithium or lithium-ion battery thermal runaway process, and the resulting effects on the enclosure.     

超声辅助生物淋滤废旧Zn-C电池锌锰溶出的研究

以氧化硫硫杆菌(A.thiooxidans)为淋滤菌株对废旧Zn-C电池电极材料中的Zn、Mn进行了生物浸提,比较研究了化学浸提、生物淋滤和不同超声辅助方法生物淋滤体系下的Zn、Mn的溶出效率及溶出动力学.结果表明:不同超声辅助方法中,超声+生物淋滤体系Zn、Mn溶出最优,Zn、Mn的最大溶出率分别为94.2%和65.5%,并提高了溶释速率.此外,对于Mn的溶出,化学淋滤体系符合边界层扩散控制模型,生物淋滤和超声+生物淋滤体系符合收缩核Stoke's regime模型,而Zn的溶出均符合化学反应控制模型.     

A mechanical pre-treatment process for the valorization of useful fractions from spent batteries

In this paper the authors propose a full-scale plant aimed to pre-treat spent batteries in order to obtain cleaned useful fractions (magnetic and non-magnetic metals, paper, plastic, a fine-sized material made of a metal-carbon mixture). The treating process was designed after having analyzed and tested a representative sample coming from the whole amount of spent batteries collected in 1 month by the public service in and around Turin. The analyses performed on the sample allowed the authors to determine its in-percentage composition in term of type of batteries: 60-70% b.w. (by weight) alkaline, 25-30% b.w. Zn-C and 5-10% b.w. other types. For each type, the composition in term of size (AAA or LR03; AA or LR6; C or LR14; D or LR20; 9 V or 6F22A; 4.5 V or 3R12A) has also been determined.The treatment for the recovery of secondary raw materials foresees the following phases:

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separation of useful types/sizes of exhaust batteries to undergo further treatments by means of a first sieving process;

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liberation of the single components taking advantage of a crushing operation;

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separation of a fine-sized material (to subject to pyro or hydro metallurgic recovery) from a coarse-sized material (to send to secondary smelt foundries and incinerators) by means of a second sieving phase.

On the basis of the results obtained from the crushing/sieving laboratory tests and the chemical characterization, a full-scale plant able to treat about 76,000 t/y of spent batteries has been designed. The cost analysis performed on the proposed treatment plant has given back a unit pre-treatment cost equal to 3€ per ton of processed spent batteries.     

Multi-factor principle for electrolyte additive molecule design for facilitating the development of electrolyte chemistry

When I read the paper"Electrolytes enriched by potassium perfluorinated sulfonates for lithium metal batteries"from Prof. Jianmin Ma's group, which was published in Science Bulletin (doi.org/10.1016/j.scib.2020.09.018), I felt excited as presented a multi-factor principle for applying potassium perfluorinated sulfonates to suppress the dendrite growth and protect the cathode from the viewpoint of electrolyte additives. The effects of these additives are revealed through experimental results, molecular dynamics simulations and first-principle calculations. Specifically, it involves the influence of additives on Li+ solvation structure, solid electrolyte interphase (SEI), Li growth and nucleation. Following the guidance of the multi-factor principle, every part of the additive molecule should be utilized to regulate electrolytes. This multi-factor principle for electrolyte additive molecule design (EAMD) offers a unique insight on understanding the electrochemical behavior of ion-type electrolyte additives on both the Li metal anode and high-voltage cathode. In these regards, I would be delighted to write a highlight for this innovative work and, hopefully, it may raise more interest in the areas of electrolyte additives.     

细水雾对锂离子电池热失控抑制作用的实验研究

为研究细水雾对锂离子电池热失控的抑制作用,利用自设计细水雾实验装置对18650型锂离子电池热失控进行抑制实验,对比两节电池依次燃爆和不同阶段使用细水雾的温度曲线。研究表明,细水雾对于抑制锂离子电池热失控有效,但不同热失控阶段细水雾抑温效果差异较大,结合锂离子电池多米诺效应和机载灭火设备适航性要求,应尽可能将细水雾喷雾时间节点靠近初次爆炸的时间节点。提出通过准确探测初次爆炸发生和进一步增强细水雾抑制作用来控制锂离子电池热失控及多米诺效应的发生和传播。     

废镉镍电池中镉优先浸出工艺

通过CdO、NiO酸浸反应的热力学和动力学研究 ,得知CdO、NiO二者的浸出条件有较大差异 ,实验确定了废镉镍电池中镉优先浸出的工艺条件 :5 0℃、pH =2的硫酸溶液中浸 5 0min ,在此工艺条件下 ,镉能 10 0 %浸出 ,而镍的浸出率只有 2 5 %。     

锂离子电池安全性特点及热模型研究

锂离子电池的安全问题越来越受到重视.本文从锂离子电池热安全性特点着手,分析了锂离子电池的着火、爆炸和电解液泄漏等安全事故特点.简单介绍了锂离子电池主要材料的产热特性、相互反应产热特性.讨论了锂离子电池热模型建立的两种途径,即量热仪途径和化学反应途径,通过这些热模型的建立,来指导锂离子电池的安全设计和管理.     

废旧锌锰电池锌锰元素的分析表征

为了解废旧锌锰电池的锌锰元素特征,以废旧碱性(A-A)和酸性(Zn-C)电池为研究对象,采用化学分析、BCR连续萃取技术、SEM-EDS和XRD等手段对拆分的电池正、负电极材料中的锌锰元素进行了分析表征.实验表明:废旧碱性(A-A)电池中Mn、Zn分别占到正极材料质量的49.2%、10.3%,以Zn Mn2O4四方体锌锰矿结构晶体存在;Zn占负极材料的52.5%,以Zn O晶体存在;废旧酸性(Zn-C)电池混合电解质中,Mn、Zn各占41.8%和25.2%,分别以Zn Mn2O4、Mn O2、Zn5(OH)8Cl2·H2O和Zn(NH3)2Cl2等晶体存在.BCR处理结果显示,A-A电池正极和Zn-C电池混合电解质中,Mn主要为残渣态较难酸释,而A-A电池负极中的Zn易于回收.     

浅谈手机废旧电池的回收利用

移动通信的快速发展和手机的大量使用,手机废旧电池给环境带来的危害必将日益明显,但目前关于废旧手机电池的研究很少,主要是一些国外的报道,文章就几种手机电池的组成、危害及回收工艺进行了综合分析,并对电池回收过程提出了几点建议,希望对我国的手机废旧电池的回收利用有所帮助.     

从废旧锌锰电池中回收汞和铵的工艺研究

针对废旧锌锰电池中汞分散存在给回收处理废旧锌锰电池工作完全回收汞所带来的困难 ,利用汞和铵的性质特点 ,找到了从废旧锌锰电池中集中回收汞和铵的工艺条件 ,为废旧锌锰电池的资源化和防止二次污染创造了有利条件。