E-bike explosions and the battery fire risk

Sam Hawley: Hi, I’m Sam Hawley, coming to you from Gadigal land. This is ABC News Daily. Electric vehicles, electric bikes, electric scooters, they’re becoming more prevalent and part of our everyday lives. But as we make the green transition, the dangers of lithium ion batteries that power these devices and many others are becoming more apparent. Today, the Lead Technology Translator from the University of New South Wales, Matthew Priestley, on what causes the battery fires and how to reduce the risk.

Matthew, there was a fire earlier this year at a Sydney backpackers hostel, and the security camera footage was pretty dramatic. It shows flames bursting out of the room.

ABC News clip: 70 people were forced to flee the Mad Monkey Hostel in Potts Point as the fire and smoke took hold…

Hostel fire witness: I saw like a huge noise at the at the hallway and I went out to see what happened…

Hostel fire witness: So I’ve got out and at that point you can actually see like a kind of mist of smoke coming around the corner, which for me was the point. I was like, let’s go, let’s go.

ABC News clip: They were confronted with some very dark smoke, low visibility and very intense heat…

Sam Hawley: A French backpacker was burned on the leg as he ran away, and firefighters quickly flagged it looked like an e-bike battery fire.

Matthew Priestly: Yes. Yeah, it sounds like a pretty unfortunate incident, and unfortunately, there’s not enough regulation in that sector and a lot of the products that are out there don’t have the level of design in the battery or in what’s called the battery management system to keep us as safe as what we really need to be kept.

Sam Hawley: Yeah. All right. It was pretty dramatic, and it’s not that uncommon. What else have we seen exploding?

Matthew Priestly: Yeah, so there’s been other incidents in Australia. There’s been a few in electric vehicle fires and also a grid energy storage battery, a lithium.

ABC News clip: Tesla battery unit ablaze. Burning at a brand new facility near Rockhampton.

ABC News clip: Illegally dumped lithium ion batteries are causing nearly 40 fires a day at recycling facilities and landfills around the country.

ABC News clip: Wa fire authorities say the number of building fires caused by lithium ion batteries has almost doubled in the past three years. In the state…

Matthew Priestly: What we’ve seen, though, is that in the e-mobility and e-bike space, yes, there are higher risk there. In my view, just because of the fact that it’s much easier for a manufacturer to make one of them because they’re lower cost, whereas it’s obviously very expensive to make an electric vehicle and a grid energy storage battery. So generally it’s the reputable manufacturers that are making those products. Unfortunately, it’s easy for non reputable manufacturers to go ahead and make an e-bike or e-scooter.

Sam Hawley: So just explain a bit further what’s happening inside the battery that then creates the fireball. It’s a bit complicated…

Matthew Priestly: It is. A lithium ion battery is actually quite a simple mechanism the way it stores and discharges energy. But what ends up happening is there’s this thing called thermal runaway. And basically, if one of the cells inside of the battery gets to a temperature that’s past this critical point, then the battery temperature will exponentially increase very fast, and it can go to above 500°C quite quickly. And in that situation, unfortunately, a battery fire can start obviously at that temperature. There’s also the potential for an explosion and the potential for the emission of toxic gases. So if you see one of these batteries lighting up, do not approach it because there can be those toxic gases there which you can inhale. And of course that can be potentially deadly.

Sam Hawley: Yeah. And to add to that, it’s really hard to put these fires out, isn’t it?

Matthew Priestly: It is. And that stems from the fact that once you’ve gone past that critical temperature point at a cell, you actually need to bring the temperature back under that point in order to make the battery safe again, to stop there being a potential for another ignition of fire or explosion risk. So what that means is you may extinguish the fire. So put out the fire on the battery. But if the temperature is still above that critical point, well, it may continue to increase again. You may get a reignition of the lithium ion battery many times after that. That’s a real challenge in things like electric vehicle fires, because when you’re trying to get the water from the hoses to the battery unit, unfortunately the rest of the car’s in the way, which means it’s very difficult to cool the battery unit just by spraying water onto the car, because very little of that water actually gets to where the battery is. So it means often we end up needing to to let these these vehicles burn, particularly if they’re in an area that’s, that’s safe to do so in the outside somewhere.

Sam Hawley: So the risks are not insignificant. And I even saw a story of a man who lost his house in a lithium ion battery fire.

ABC News clip: The cause? An old e-bike battery charging in the garage.

ABC News clip: Once the ceiling dropped, everything ignited inside. And we had tile floors. Made no difference at all. Just the extremity of the heat. Cracked tiles just destroyed absolutely everything inside.

Sam Hawley: So, Matthew, just say you do have an e-bike and you live in an apartment, and the only place that you can charge that e-bike is actually inside, perhaps even in your bedroom. What should you do?

Matthew Priestly: Well, I think in that situation it’s good practice to not charge it overnight. So charge it while you’re there and make sure that once it’s finished charging, that you take it off the charger. And if you’re finding there’s there’s any issues, so there’s an indicator light on the either the charger or the battery, then indicates that there could be a potential fault. Then you need to follow the manufacturer’s instructions. Definitely read the manual on these devices. It will give you a an estimated charge time. If it’s taking a lot longer than that charge time, there may be an issue with the battery unit, so potentially you should stop charging that device.

Sam Hawley: So Matthew, we’re getting more and more of these lithium ion batteries in our homes. People might be surprised how prevalent they are. They might even end up with one under the Christmas tree this holiday season. So what types of other things are these batteries in?

Matthew Priestly: They’re in a range of different devices. And people will be surprised how quickly lithium ion batteries have proliferated into our lives. The reason for that is the fact that they can store so much energy in a really small, portable volume and low weight. That means that in things like mobile phones, which typically use lithium ion batteries, we’re able to essentially go for longer on one charge and have a lighter weight phone than other battery technologies where we see lithium ion batteries, obviously mobile phones, a lot of portable consumer electronic devices. So things like digital cameras, surveillance technologies, many of those, we also see them in power tools. So if you get a high quality power tool, they’ll generally have a lithium ion battery in it. If it’s a portable non corded one, you can also see them in your power packs, things like that. So particularly what’s called an uninterruptible power supply. So they often have lithium ion batteries and those as well.

Sam Hawley: Hmm. And are they all at risk of blowing up?

Matthew Priestly: Look, I think it’s one of those things where every device that stores energy, there’s a risk. So if you look at something like your car, your combustion engine car, there’s fuel in that car, right? We’re used to dealing with that risk. So if we go to fuel up a petrol powered car, we know that we shouldn’t light a flame next to the bowser as we’re fuelling up, because that would be an incredibly risky thing to do. And there’s a potential for an explosion risk. Unfortunately, what we’ve found is that a lot of people aren’t actually trained in the risks associated with lithium ion batteries. It’s very important that we learn how to use these things safely and treat them with respect. You know, you wouldn’t be throwing around cans of gasoline, uh, you know, because we’re aware of what the risks are. However, we’re happy to throw around our devices that have lithium ion batteries in them. And that’s probably because of the fact that we’re used to dealing with batteries like double A and triple A batteries, which have a very low risk compared to things like lithium ion batteries. And a lot of people think they’re very similar technology when they’re actually quite different. And the risks are very different.

Sam Hawley: Mhm. Right. Well we also mentioned before EVs, of course, there was recently a fire at Sydney Airport involving an EV…

ABC News clip: These five burnt out cars are the result of one lithium ion battery gone wrong. It’s one of two separate incidents where EVs have caught fire in New South Wales this week.

Sam Hawley: Are these really, Matthew, just potential bombs sitting in our driveways? If you are lucky enough to have an electric vehicle in your driveway…

Matthew Priestly: I think with that particular incident, there was actually damage to a car and someone had removed the lithium ion battery unit out of the car, which is an incredibly unsafe thing to do. And yet again, that comes back down to the training side of things. In the case of electric vehicles, I mean, the NRMA has come out and said that there’s, you know, a lower risk and there’s per capita less fire and explosions than a combustion engine car. So we need to be aware of that. The fact that there are also risks of fire with our petrol cars that we have at home, that’s also can be seen as a bomb too. Um, yes. So I think there are similar risks, but at this point in time, it seems like there’s less risk with an electric vehicle than a combustion engine car. One of the challenges at the moment is how do we extinguish and fight a lithium ion battery fire in an electric vehicle? And that’s because it’s very new technology, and we’re developing ways in which to do that right now. But that’s one of the challenges.

Sam Hawley: So, Matthew, what then do shoppers need to be aware of when they go and buy products with lithium ion batteries in them?

Matthew Priestly: So I think there’s counterfeit devices out there, which often if you go on to an online marketplace portal and purchase these devices, you may accidentally purchase one that is not from the brand that you think it is. It looks very similar, so people need to be aware of that. They need to be aware of the fact that sometimes these counterfeit devices may be ones that are built from non-reputable manufacturers that are just cutting the corners of good design in both the battery and the battery management system. Or they may be a reputable brand of battery that’s actually had a fault, and they’ve gone and fixed it and resold it. But you’re not aware of that and not aware of how good that fix actually was. So you need to be very careful with that type of thing. So it’s a good idea. If you’re not certain to go to the actual manufacturer or one of their retailers and purchase it directly from there. When it comes down to regulation, unfortunately there’s not much regulation to stop those devices coming into Australia, and there’s unfortunately very little regulation on exactly what a battery management system should be doing for these types of batteries, and how it moves these batteries into a safe space. If there is an issue detected, and in some cases there is a very, very substandard battery management system, or not even one at all, which is very concerning.

Sam Hawley: And as we mentioned, these batteries are really prevalent and they’re not going away, of course. So what are your tips for staying safe in your own home when you have these batteries?

Matthew Priestly: They’re some of the key things is to make sure that when you’re charging your battery, you’re using the right charger for the actual battery device. A lot of these batteries have an overcharge protection cut off feature, so that means it won’t let the batteries overcharge. However, it’s good practice not to rely on that feature, and once the battery’s finished charging, take it off the charger. It’s also good practice to make sure where you’re charging it. Make sure it’s free of chemicals and water. The other thing is, if you drop a battery, so particularly things like a power tool battery, say you drop a tool off the roof. Unfortunately, that battery is likely sustained some damage. You can’t tell what that damage is. So it’s very good practice in that point to treat that as a potentially faulted device which may fail.

Sam Hawley: All right. But we shouldn’t be too concerned by what’s under the Christmas tree this year, I hope…

Matthew Priestly: No, no, look, I wouldn’t be too concerned. I think as long as you treat these devices with respect, then there shouldn’t be a problem. And as long as you’re purchasing them from reputable retailers, then yet again, you should have a high quality battery under the tree if you’ve got a present that has one.

Sam Hawley: Matthew Priestley is the lead technology translator from the University of New South Wales. This episode was produced by Bridget Fitzgerald, Nell Whitehead, Sam Dunn and Anna John, who also did the mix. Our supervising producer is David Coady. I’m Sam Hawley. ABC News Daily will be back again tomorrow. Thanks for listening.