EV battery fires are very intense.

On the race track, things can go bad in a hurry. And, when it comes to electrical fires, it can escalate exponentially into high-risk territory. As electric vehicles and battery-powered technology become more mainstream, the potential for possible problems also increases precipitously.

Recently, the safety team at Wagler Motorsports Park in Lyons, Indiana, handled an alarming emergency involving an electric Junior Dragster and an explosive battery fire. Fortunately, everyone escaped unharmed, and the lessons they learned in the mitigation process will hopefully help many other track operators, racers, and crew.

The incident began while the Junior Dragster was still on the track. Its driver finished the run, departed the racing surface, and approached the ET ticket shack, as usual. The facility’s owner, Jeremy Wagler, was working trackside and saw that the whole back of the car was full of smoke as it approached.

At first, Wagler assumed the diminutive dragster simply had an engine issue, but as it got closer, Wagler realized it was far different – it was a battery fire – and he immediately called on the radio for the safety crew to come quickly. To further intensify the issue, Wagler saw that the large battery, roughly 12”x12”x16” and weighing approximately 50 pounds, had actually burst and exploded inside its case directly underneath the driver’s seat.

“The chemicals were on him [the driver] and had burnt his helmet, his fire suit, everything,” recalled Wagler of the harrowing incident where, thankfully, the young driver was able to safely get out of the car. “Within seconds, it blew up with six-foot tall flames. It was on fire, hissing like crazy, and everyone was moving quickly to get away from the area.”

Wagler wisely called his colleague, Ben Wrightsman, Founder and Lead Advisor of XC TECHnology who is a 30+ year veteran in the battery industry for urgent advice. Wrightsman directed Wagler’s team to cover the battery with sand from the pit area to contain the burning battery.

It was clear to the safety team at Wagler Motorsports Park that standard safety protocols wouldn’t cover this fire.

To make the situation even more concerning, Wrightsman told Wagler the inhaling the smoke and chemicals released by the battery fire is harmful since they’re hazardous and should be avoided. This was a problem as everyone was around it in the heat of the moment, and the wind was blowing the nasty-smelling smoke directly into the race trailers and pit area.

Wrightsman also stressed the fact that no matter what fire extinguishers the team used, they wouldn’t be able to extinguish the battery fire once it was in a thermal runaway state. So, the next best thing they should do is try to keep the car around the battery as cool as possible to avoid further propagation, and that water on the battery itself can prolong the event, ideally for control measures usage.

“We were able to get close enough to the dragster to cut the bracket off of the battery with the jaws of life we keep in our ambulance. If we couldn’t have got the battery out, we planned to pick up the car with the excavator and put it in the sand pit beside the return road.,” shared Wagler. While the safety crew was cutting the battery out and keeping the fire contained to the battery area only, Jeremy went and tracked the excavator to the return lane to dig the hole to bury the battery “Ben [Wrightsman] recommended we bury the battery, then he would come by the next day to dismantle and inspect it, and properly dispose of the battery per regulations.”

For those wondering, yes, Wagler did call the fire department, but track staff had the battery in the ground before officials arrived.

Thanks to guidance and expert direction from Wrightsman, Wagler Motorsports Park was able to successfully and safely contain the battery while saving the dragster (and its driver) from complete catastrophe. “We’re putting a grave site out here for EVs,” he joked of the impromptu burial site that has since become permanent at WMP.

Electric Junior Dragsters, and electric vehicles in general, are becoming more common at the drag strip, as the vehicles basically stay dialed in regardless of the weather with no traditional tuning required, and are practically maintenance-free.

The Junior Dragster in question was using a lithium-ion battery pack (with lithium cobalt oxide or “LCO” chemistry) manufactured by Lonestar EV Performance. It was equipped to utilize an external battery management system (BMS) which would support cell balancing, as well as voltage and temperature monitoring. Although a BMS can support a relatively safe system, it does not ensure fail-safe battery operation or management, however, such a system was not present on the Junior Dragster at the time of the incident.

“The most likely cause of the problem here was the cells being stressed after this unmonitored life-cycling (roughly two years), as a function of unbalanced usage, that caused one or more cells to become the weak link,” stated Wrightsman. “Typically, this would be because of a rise in impedance over unbalanced use, capacity fade that resulted in higher C rate (causing the breakdown of electrode structure), or internal parallel failure (connection) resulting in lower capacity series set and over discharge. Without proper understanding, usage, and inclusion of a BMS and supporting hardware, lots of issues can arise causing these full-on failures.”

The Wagler team had to bury the battery to deal with the fire.

The chemical reaction that occurs during an electric vehicle lithium-ion battery fire is a dynamic chain of events that begins with a catalyst. At first, the atomized electrolyte that is venting is ignited, and thermal runaway (a self-perpetuating process that occurs when the temperature of an electrical component or battery increases beyond its ability to dissipate heat) rapidly spirals out of control.

Additionally, when a battery catches on fire, often in ranges upwards of 1,600-2,000C at peak, which rivals ethanol and alcohol-fueled fires. Additionally, there are chemicals are released into the air during a battery fire. Those chemicals can not only pose significant problems in terms of fire extinguishing, but can also be a serious risk to human lungs, clothing, and other materials.

According to Wrightsman, “LCO chemistry will release hydrogen flouride, phosphoryl fluoride, cobalt oxide, hydroxide, hydrochloric acid (with water/humidity present), and other flourides/flourines. Even with fire suits and when no flame or larger thermal events are present, simple venting events can still impact the clothing and compromise the materials’ effectiveness so that they are no longer safe to be used.”

For those who find themselves facing an electric vehicle battery fire, though, Wrightsman does have some solid advice. “Cool the surrounding areas to reduce propagation and ideally allow for the thermal reaction to run its course while monitoring surroundings,” he explained, emphasizing the fact that the safety of (and risk to) life is always the first priority.

“Water, sand, dirt, vermiculite, fire blankets on propagation risk site, not placed on the event, and other lithium-ion battery tested products are beneficial to fire control/mitigation for the balance of at-risk stranded energy, but many are dependent on the pack and system design,” Wrightsman explains.

The battery was still very hot even after being pulled from the ground after being buried.

For other tracks that will almost certainly face scenarios similar to what happened at Wagler in the future, proper training and preparedness is key. Additionally, having a predetermined site dedicated to containment and mitigation is ideal. If it’s not possible to bury the battery in a designated area as not all facilities are fortunate enough to have an excavator on site like Wagler, covering the battery with sand to provide control to the event is the next best option.

“I’d recommend getting some large steel drums and putting sand in the bottom, and having a large pile of sand beside it, so you could use the tractor with forks to lift the battery in,” suggested Wagler in regards to an easy makeshift quarantine. “And then cover it with sand from the pile.”

Ultimately, track operators have to make the tough choice whether or not to permit electric vehicles to participate in events on their property. As enthusiasts and engineers push the limits of what’s possible, innovation brings inherent danger as new technologies are tested.

The fire did significant damage to the dragster and was very close to the driver.

Wagler warns, though, that with regular full-size electric vehicles such as Teslas, unlike a junior dragster, you likely won’t be able to just throw some sand on it. “Unless you have the equipment and the training necessary to deal with a fire or emergency, I wouldn’t have EV cars racing unless you make them sign a waiver saying you might have to cause damage to their car by throwing a ton of sand over the top of it.”

Furthermore, Wagler cautions track owners and operators to consider the potential secondary fallout from an electric vehicle fire while it’s still in the pits, or in a trailer, as the trailers on either side would then be at risk of also catching fire.

Similarly, for racers, it’s imperative to always follow proper battery handling and storage protocols as dictated by manufacturers. “Utilize charging systems that include full cell monitoring for temperature and voltage across all cells, have the battery’s health regularly verified, check often for swollen or leaking cells, install and use a battery management system, and, if possible, charge prior to use. It’s also helpful to position the battery in a location that is easily accessible in case of emergency,” added Wrightsman.

“I learned a lot. And I’d like to share that knowledge with other tracks, racers, and spectators because this scared the crap out of us,” admitted Wagler. “The biggest lesson learned would be, as soon as possible, get everyone away from the battery fire to keep the chemicals and smoke inhalation away so you do not cause any health issues for anyone.”

EVs are the next frontier in high-performance vehicles and they will require a new approach to safety. Hopefully, other motorsports facilities look at this situation and use it as a learning experience. Thankfully Jeremy Wagler and his team made the right calls and reacted quickly to this fire.