Arizona regulator warns of ‘unacceptable hazards’ of lithium batteries

Arizona regulator warns of ‘unacceptable hazards’ of lithium batteries

Arizona regulator warns of ‘unacceptable hazards’ of lithium batteries 150 150 Batteries International

August 28, 2019: An August 2 letter from Arizona regulator Sandra Kennedy says lithium batteries should not be used at utility scale — and she warns that a 250MW lithium ion battery has the energy equivalent to 215 tons of TNT.

The letter, to the Arizona Public Service Company, is in response to two battery fires that were caused when lithium battery cells failed.

The two fires, at the APS Elden Substation facility in Flagstaff in 2012 and the APS McMicken Energy Storage Facility in Surprise in 2019, are examples of why a chemistry should not be used if it ‘includes compounds that can release hydrogen fluoride in the event of a fire and/or explosion’, the letter says.

The investigation also discovered that there was inadequate circuit protection and issues with the temperature sensors within the modules.

“All of this points to unacceptable hazards and risks presented by the current utility-scale lithium ion battery systems using chemistries that could release hydrogen fluoride in the event of a fire or explosion,” the letter says.

It then quotes George Crabtree, director of Argonne National Laboratory’s Joint Center for Energy Storage Research, who says the problem of thermal runaway with lithium batteries is very well known.

“Knowing now how easily a fire or explosion can evidently occur at these types of relatively small (2MW) lithium ion battery facilities, it appears that a similar fire event at a very large lithium facility (250MW+) would have very severe and potentially catastrophic consequences, and that responders would have a very difficult time trying to handle such an incident,” the letter says.

However, while suggesting several alternatives to using lithium ion batteries, the letter does not suggest lead acid batteries would be a suitable option — even though it compares nickel-iron batteries with lead-acid.

It also says that other lithium chemistries do not carry the same risks.

Lisa Dry, director of strategic communications with Battery Council International, said the organization had approached the Commission.

“BCI reached out to Commissioner Kennedy directly and provided information for her to consider lead batteries for energy storage,” Dry said. “Her policy staff responded immediately and noted that her letter had generated many responses and ‘brought to light information about a variety of energy storage technologies that were previously unknown’.

“We have provided additional information and offered to provide a technical expert to meet with her or staff to answer any additional questions they may have.”

“The explosive nature of lithium runaway fires has been well known by other parts of the business for a long time,” says one industry commentator. “It is astonishing that the utility sector is just becoming aware of it. They’re following a lithium-only bandwagon rather than thinking of suitability.”

Separately, news reports suggest that South Korea has suffered more than 20 separate lithium related fires this year.