Unlike traditional methods of electric and hybrid vehicle battery disposal, which try to manage and contain energy, a new “Maui Method” developed by the County of Maui eliminates the risk altogether.

A full documentary video of the approach is now available on the Maui Emergency Management Agency’s (MEMA) YouTube channel: https://www.youtube.com/@MauiEmergencyManagementAgency.

The “Maui Method” safely turns dangerous, damaged lithium-ion batteries into nonhazardous waste by fully discharging them in brine, destroying their structure and eliminating safety hazards before transport or disposal. The process prevents fires before they start, enables shipping, works at scale and fills a national gap.

It was tested toward the end of last year during MEMA’s Wildfire Risk Reduction project in Ukumehame. Over approximately five weeks, crews stabilized, decommissioned, destroyed and containerized 13 tons of batteries using the “Maui Method.”

Now, the U.S. Environmental Protection Agency recommends the “Maui Method” as the preferred approach for lithium-ion battery disposal.

“The ‘Maui Method’ shows what is possible when innovation, collaboration and expertise come together,” MEMA Administrator Amos Lonokailua-Hewett said. “Considered one of the first full-scale, nondisaster initiatives of its kind, this operation sets a national and even global precedent for safe and effective EV battery management while protecting our community and environment.”

“Up till about this point, there really hasn’t been any good way of disposing of lithium-ion batteries. A lot of them are going into people’s trash cans and ending up in landfills and causing tons of fires, burning up garbage trucks all over the place and causing millions of dollars of damage for local entities,” said Justin Marquez of EPA’s National Lithium-Ion Battery Task Force. “Our ultimate goal is for this ‘Maui Method,’ or some version of it that accomplishes the same goals, to be rolled out across the entire nation and even potentially globally.”

Lithium-ion batteries — especially from electric and hybrid vehicles — become extremely dangerous when damaged:

• They can enter thermal runaway (self-heating that leads to fire or explosion)
• Fires cannot be put out reliably with water or foam
• They emit toxic gases
• If one battery ignites, it can set off others nearby
• Shipping intact, damaged batteries (especially by sea) is catastrophic if they ignite

The “Maui Method” was developed in response to the 2023 Lahaina fire, which scattered, buried or altered thousands of damaged EV batteries. The Valley Isle has no battery disposal facility, and shippers refused to transport the batteries citing safety risks. The approach was created to neutralize the batteries before transport, turning them into nonhazardous waste. Later, the method was deployed during the Los Angeles wildfires.

The heart of the “Maui Method” is brining, or submerging batteries in a saltwater solution. Saltwater is conductive, so it slowly and safely pulls remaining energy out of the battery, rather than letting it release all at once as heat or fire.

Led by the County of Maui, the Ukumehame project involving 13 tons of batteries followed strict safety protocols, including 24/7 security, continuous air monitoring and a dedicated on-site emergency response team. All work in November and December 2025 was conducted under the direct oversight of the Hawaiʻi Department of Health, with technical guidance from the EPA.

For more information on MEMA’s hazard mitigation initiatives, visit mauicounty.gov/MEMA.