Questions are still awaiting answers as Arizona Public Service Co. investigates the cause of an explosion April 19 in a 2-MW/2-MWh grid-connected energy-storage battery facility in Surprise, Ariz. The incident sent eight firefighters and a police officer to the hospital with non-life-threatening injuries, but APS has revealed few of its investigation’s findings despite promising in a June 5 statement that “periodic updates will be posted to report on the process and progress being made.”
The explosion of the lithium-ion (Li-ion) battery bank drew new attention to the flammable battery technology, which has caused spontaneous fires in Boeing airliners and Samsung smart phones in recent years.
“尽管我们不知道APS发生了什么事，但很可能是同样的挑战，” Argonne国家实验室储能研究中心主任乔治·W·克拉布特里（George W. Crabtree）说。“如果将锂离子电池的温度高于150°C以上，则在阴极和电解质之间发生反应，不需要空气中的任何氧气才能进行，并且该反应会释放热量。释放的热量进一步加热了电池。这使得反应变得更快，这就是他们所说的“热失控”。这一直是锂离子电池的主要安全问题。众所周知。”
4月19日事件发生在APS McMicken储能设施中，这是两个相同的电池库之一，每个电池库之一大约相当于运输容器的大小，最近建造的旨在帮助存储太阳能以更好地满足日落后的电源需求。电池系统由27个架子组成，分别为14个模块，共有378个模块的锂离子电池。该设施于2016年开始建设，并于2017年上线。
APS拥有超过1,700兆瓦的可再生能源能力，APS继续在太阳能开发方面进行大量投资，包括全天候载荷服务所需的能源存储电池。2019年2月，该公用事业公司宣布了计划在2025年之前将850兆瓦的电池存储和至少100兆瓦的新太阳能发电添加到其系统中。
在2000年之前，与网格连接的能源存储的安装基础可以忽略不计，公用事业行业的经验很薄，但是在美国的主要设施中，只有三个灾难性的失败：夏威夷的一个，亚利桑那州的APS系统中有两个。2012年，亚利桑那州弗拉格斯塔夫（Flagstaff）附近的1.5兆瓦APS电池设施着火了。该公用事业公司从对该事件的调查中汲取了教训，并继续取得了电池设计和安全标准的进步，以扩大其固定存储空间以进行可再生能源。
根据加利福尼亚州帕洛阿尔托电力研究所的储能计划经理本·考恩（Ben Kaun）的说法，建立该技术的一般事件时间表仍然是早期的。“我们已经与许多行业参与者进行了讨论开发事件数据库，以便我们可以理解……当发生不同类型的失败时发生的后果。”他告诉Enr。新利luck
“What we’re learning over time is that it’s not necessarily always a battery problem,” Kaun says. “It’s not necessarily that the failures are occurring within the battery. There are other systems that make up an energy storage system, which can result in failures, and those failures can result in further failures of the battery.”
Despite the recorded incidents of bursting into flames, Li-ion batteries now make up 98% to 99% of all new battery-type energy storage systems, and “there’s been rapid adoption in the last couple of years in particular,” says Kaun. Potentially competing technologies “are either not in the right cost point now or are at earlier technology-readiness levels, still in the R&D phase where one might speculate that they could one day take market share from Li-ion,” he says.
A safer technology may be so-called flow batteries, which “operate with liquid anodes and cathodes instead of solid anodes and cathodes that you have in most batteries,” Crabtree says. “The advantage of that for the grid is that if you make the tank 10 times bigger, put 10 times more liquid in it, you store 10 times more energy; it scales perfectly linearly. That is not true of Li-ion.” A recent BloombergNEF report indicates the levelized cost of electricity from batteries has fallen faster than the cost of solar panels. “That could easily happen to flow batteries as they get into high production mode,” he says.
