Recent e-bike, grid battery fires have raised concerns about firefighting challenges, prevention
Firefighters have raised alarms about hot, fast, hard-to-extinguish fires in lithium batteries from e-bikes in people's homes (including one in Toronto just this week) and huge storage batteries at a P.E.I. solar farm last month.
asserted
Firefighters → raise → farm
Concerns about lithium battery fires have led to bans of electric bikes and cars in some buildings, public transit and ferries, causing problems for people who rely on them.
asserted
who → lead → them
They've also made some people hesitant about trying electric vehicles.
asserted
people → make → vehicles
Here's a closer look at why lithium battery fires are a challenge and what can be done to minimize the risks.
asserted
what → do → risks
Canadian fire departments don't track them in a consistent way, but a survey from the Canadian Association of Fire Chiefs estimates there were 1,500 fires started by lithium batteries in 600 communities across the country last year.
asserted
survey → track → country
Their numbers are growing exponentially with the numbers of lithium battery-powered devices, says Paul Boissoneault, president of the association and chief of the Oakville Fire Department.
asserted
Boissoneault → grow → Department
Lithium battery fires are most common for devices found in people's homes, especially e-bikes and e-scooters.
asserted
fires → find → homes
EV and energy storage batteries are far rarer, as they're rigorously tested and have built-in safety features like temperature sensors and systems that cool battery cells as needed.
asserted
that → test → cells
Canada-wide statistics on EV fires aren't available, although U.S. data suggests they're extremely uncommon compared to fires in gas-powered vehicles.
uncertain
they → suggest → vehicles
Grid storage battery fires are even less common — a global database from the Electric Power Research Institute shows the one in P.E.I. was one of only six worldwide this year.
asserted
one → show → six
What causes lithium battery fires?
asserted
What → cause → fires
Batteries rely on the separation of their positive and negative terminals.
asserted
Batteries → rely → terminals
That forces electrons to move through the device you're powering to get from one end of the battery to the other.
asserted
you → force → other
A barrier material keeps the terminals separated.
asserted
terminals → keep → ?
When a hole (effectively a short circuit) forms in that barrier, fire happens, said Randy Narine, a professional firefighter in Brampton, Ont., who studies lithium battery safety through his company Clean Core Research, in an interview with CBC's What on Earth?
asserted
who → form → Earth
That hole can be caused by wear and tear over time or from damage, such as a collision or someone dropping a battery from a smaller device, such as an e-bike.
asserted
someone → cause → bike
Lithium battery fires can also be started from overheating — due to overcharging or improper charging (such as with the wrong charger) or heat exposure from an external heat source, including a fire in a nearby battery cell in the same battery, since many batteries contain multiple cells.
asserted
batteries → start → cells
What makes them dangerous compared to other fires?
asserted
them → make → fires
They can burn "hotter and faster" than other fires, Boissoneault said.
asserted
Boissoneault → burn → fires
At a certain temperature, lithium batteries reach "thermal runaway," where heat triggers and speeds up chemical reactions in the battery that generate more heat.
asserted
that → reach → heat
This can lead to a "massive chain reaction" and a potentially explosive fire, Narine said.
asserted
Narine → lead → reaction
They make their own oxygen.
asserted
They → make → oxygen
One of the battery's terminals is made of a metal oxide that breaks down into metal and oxygen gas during a fire, further sustaining the fire.
asserted
that → make → fire
That means normal techniques to smother fires don't work.
asserted
techniques → mean → fires
They generate toxic substances such as hydrogen fluoride as materials in the battery break down in the heat.
asserted
materials → generate → heat
They can also contaminate firefighters' clothing and equipment with toxic compounds such as formaldehyde and heavy metals that need to be removed afterward.
asserted
that → contaminate → formaldehyde
They can reignite hours, days or weeks later, thanks to thermal runaway and their oxygen self-generation.
asserted
They → reignite → runaway
Boissoneault said that can have implications for how the burned batteries are transported and stored after a fire.
asserted
batteries → say → fire
Firefighters don't always feel prepared for them.
asserted
Firefighters → feel → them
Boissoneault said just 40 per cent of departments surveyed had formal training on dealing with lithium battery incidents, and even fewer said they had standard operating policies and the correct equipment to deal with such emergencies.
asserted
they → say → emergencies
Many also don't have a way to decontaminate their gear after a lithium fire.
asserted
Many → have → fire
How can they be handled and extinguished?
asserted
they → handle → ?
EV fires are typically sprayed with huge amounts of water.
asserted
fires → spray → water
Narine estimated a gas car fire can be extinguished with less than 2,000 litres of water, whereas it can take tens of thousands of litres to put out a lithium battery fire.
asserted
it → estimate → fire
While water can provide cooling and can sometimes be used to protect nearby materials from catching fire, it can't actually smother the battery fire.
asserted
it → provide → fire
In many cases, fire experts say, the fire just needs to burn out.
asserted
fire → say → cases
That's particularly the case for large energy storage batteries, said experts at a fire safety panel at the Energy Storage Canada conference in Toronto in September.
asserted
experts → say → September
Adam Jakubowski, a firefighter and senior consultant with Energy Safety Response Group specializing in battery energy storage systems, said in many cases, putting water on a lithium battery fire simply prolongs a fire, which may reignite a week or month later.
uncertain
which → specialize → fire
It can also lead to water runoff that could contaminate the environment.
uncertain
that → lead → environment
What can you do to reduce the risk?
asserted
you → do → risk
…and 6 more, not listed.
The Aporia
