Truck converters Janus Electric says an internal short of a single battery cell caused the Cement Australia truck to catch fire on the West Gate Freeway late last month.
Speaking to Big Rigs at the conclusion of an exhaustive investigation process, general manager Lex Forsyth said data recovered from the truck showed that a single failed cell, one of 1050 cells in the Janus battery packs, went into a “thermal runaway” in Melbourne on November 28.
“Some trace data has shown us some variability around that particular cell for the past three weeks, in what we pick up in our battery management system, and also in our ecosystem software that manages the battery assets.
“These are characteristics that are only specific to that cell that have basically highlighted something that we can now trace and track.
“The cell exhibited some different qualities, it was putting out some different voltages during charging and discharging and give a different characteristic.
“Now we’ve been able to get that pattern we’ll be able to isolate those packs out of service prior to a thermal event and reduce the risk and obviously make the batteries safer than what they are now.”
Forsyth said it is a “reasonably easy” fix with a “little bit of coding” and algorithms, and overlaying over the top of the data with some AI.
Cement Australia’s remaining six converted electric trucks will go back on the road after the Christmas break. Forsyth said other existing clients Fennell Foresty, Qube and NewCold are already back in operation following precautionary safety checks.
“One of the challenges with EVs and batteries and battery cells, is that the cell cell provider doesn’t come to you and say here’s a list of everything that you need to watch for.
“We’ve got a list with our BMS [battery management system], but this is new data to us of we’ve seen in the characteristics of the cell, which is really good because it actually allows us to take that data and information, implement a control mechanism over it and we’re also hard-coding that
“We’re also hard-coding that data set into our BMS as now as well as an alert so that we’ll have the battery management systems in the packs, controlling the health of the pack as well as the ecosystem data. And we are now implementing a resistance check in our charge stations.
“It will extend the recharge time of the battery by about 10 minutes, but it’ll be a resistance check it on all cell resistances right through the pack every time the battery cycles through a charge station.”
After the changes Forsyth said there will now be an earlier warning in place should a truck go into a “thermal event”.
“The really good thing around our system is that as soon as there was a battery fault, we were all alerted by text messages.
“Within two minutes of getting the text message, our team was in contact with the driver.”
Forsyth said the truck was at the top of the West Gate Bridge when the driver got the battery alarm.
The pack in which the affected cell was in immediately isolated as the driver “coasted” off the bridge down to where he eventually exited the truck long before the fire started.
“He still had full power-steering, full air compressor, all of the high voltage was there.
“After he stopped the vehicle he did a key cycle, which will reset the battery alert if the systems are safe. The battery alarm was then still showing.
“He then hopped out of the vehicle and noticed smoke coming out of the battery pack. He had time to get a fire extinguisher off the vehicle and try and fight the fire.”
After using all the extinguisher and not making a difference he walked away from the truck, said Forsyth. More than seven minutes had passed between the battery alarm first sounding in the cab and the fire breaking out and the driver was never in any danger, he added.
“The stigma around batteries exploding and that they’re dangerous is so far from the truth it’s not funny.
“The battery exhausted all of its energy and the fire was put out in about an 75-80 minutes.”
The intergrity of the batteries were such that they could still be removed at the scene by the same forklift used to swap the batteries during normal operation.
“One of the things that Victorian Fire said to us was that it was really good to be able to isolate the batteries off the vehicle and do it the way that we did because they had a concern of reignition while vehicle was being towed.”
“They’re going to work out how they do that with fixed battery trucks if there is another similar issue.”
Forsyth said there are also some other good “lessons” to come out of the incident around how to fight EV fire which Janus plans to share nationally with all fire and rescue teams.
“The other interesting comment from the fire brigade was that they had been to 250 diesel truck fires in Victoria this year and this is the first EV truck fire they’ve had.
“It seems like we turn a bit of a blind eye when a diesel truck is on fire but when an EV is on fire, it’s a major issue.”
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If a “single cell failure” can cause such a catastrophe, why the F&^K would you want one towing a trailer load of cement? Lets keep in mind, this is the SECOND EV truck from Janus to catch fire following one back in July 2022!