An electric wheelchair lithium-ion battery fire at an apartment caused two people to be treated at a local hospital for smoke inhalation and extremely elevated carbon monoxide levels. Authorities say this could’ve been a lot worse.

ANN ARBOR, Mich. (FOX 2) - An electric wheelchair lithium-ion battery fire at an apartment caused two people to be treated at a local hospital for smoke inhalation and extremely elevated carbon monoxide levels. Authorities say this could’ve been a lot worse.

"These individual batteries are what went into thermal runaway and this is what created the explosive jet of the battery pack that was on the back of the (wheelchair)," said  Ann Arbor Fire Chief Michael Kennedy.

There isn't much left of a wheelchair after the battery caught fire while charging around midnight Tuesday. It caused nearly $250,000 worth of damage.

Chief Kennedy says the blaze at University Living Apartments - a retirement home, was the worst lithium-ion battery fire they’ve encountered.

"The entire apartment was floor to ceiling completely choked with smoke," he said.

The apartment building's sprinkler system kicked on – keeping the fire in check and buying firefighters some time to rescue the elderly pair inside.

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"This is about as close as it gets we are very, very fortunate," said Kennedy. "Again, our crews did an outstanding job, we had a great response time, but this very easily could’ve been a double fatal fire this morning."

There’s been an uptick in lithium battery fires over the years as the technology powering our phones, scooters, and other gadgets becomes more prevalent.

The fires usually occur when the batteries fail and that has investigators worried about this case.

"The fact that this was a new manufacturer-installed battery that failed in this condition is really quite concerning, and then also had somebody been in the wheelchair when this happened they absolutely would’ve had third-degree burns from this," Kennedy said.

Meanwhile, the Ann Arbor Fire Department will store the burnt battery in a fire containment system for the next 10 days. Lithium batteries can reignite days after they first catch fire.

Kennedy offered a word of caution to those with similar lithium-powered electric wheelchairs.

"(I) really encourage people if you’re going to have them, charge them where somebody is awake, ideally don’t charge them overnight when you’re asleep," he said. "Don’t charge them in an exit path and as always make sure you have working smoke detectors."

The investigation into the fire is far from over.  Ann Arbor will be working with the Michigan Bureau of Fire Services to determine the make and model of that battery and report it to the Consumer Product Safety Commission.

The goal is to find out if that battery fire is an isolated incident or part of a larger problem.

Why the battery caught fire and learn from its manufacturer if it's an isolated incident or part of a larger problem.

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