Over the last few months, we've seen no shortage of coverage of Chevy Bolt fires and recalls by the automotive, tech, and mainstream press. Of course, the Bolt EV / EUV recall is a big deal: it's the first 100% "full-fleet" safety recall of any mass-market EV, and the resulting fires have legitimately catastrophic consequences.
But it's worth asking: is a disproportionate amount of ink being spilled on this recall just because it's EV-related - and therefore new, different, and perhaps a bit scary?
As a Bolt owner, as a dad in a 2-EV household, and as an engineer who works on battery electronics daily, I believe a bigger-picture perspective on the Bolt recall is well-warranted.
Automotive Recalls in General
The first thing articles and posts about the Bolt recalls tend to leave out is the general prevalence of "park outdoors" fire recalls: they're nothing new. In just the last few years, many major manufacturers have issued recalls for large swaths of mass-market fossil-fueled vehicles:
- In 2017, BMW recalled over 1,000,000 cars and SUVs due to fires caused by an overheating valve in the engine. (Many claim they dragged their feet for years before admitting hundreds of fires were due to design defects.)
- From 2016 through 2021, over 2.5 million Hyundai, Kia, and Genesis sedans and crossovers have been recalled due to ABS components that can cause engine compartment fires.
- This year, Fiat Chrysler recalled all current-model-year Ram trucks with Cummins diesel engines for heater relays that can catch fire.
- GM this year recalled about 10,000 Chevy and GMC commercial vans due to short circuits that can result in vehicle fires.
- In 2019, Nissan recalled almost 400,000 cars and crossovers due to fires caused by ABS system parts.
All of these recalls included guidance to park affected vehicles outdoors, and away from other vehicles or buildings. Taken in the context of these 4,000,000+ non-EVs recalled, the 180,000-or-so Bolts GM has called back begins to sound a bit paltry.
Vehicle Fires in General
But realistically, how does the likelihood of your Bolt catching fire compare with road vehicles at large? The National Fire Protection Agency (NFPA) keeps tabs on fires of all sorts, and reports that around 0.07% of cars and trucks (or around 700 for every million on the road) end up catching fire. Meanwhile, as of this writing, there have been 19 known Bolt EV fires - which puts the likelihood of experiencing one around 0.01% or 100-in-1-million. Even considering only 2017-2019 models, responsible for all but one of the fires, the odds are still only 0.027%; 60% less likely than a fossil-fueled car fire.
That said, Bolt fires generally only occur when parked. If we limit the gas-powered vehicle fires to just those that NFPA reports occured when parked (37%) their odds-of-fire drop to about 260-in-1,000,000. Even comparing with this limited set, Bolt fires remain well under half as likely as a parked fossil-fueled vehicle catching fire, and for 2017-2019 model years are on-par.
Statistically, I don't think fully limiting fossil-fueled vehicle fires to those occurring while parked is a fair comparison. All of the root causes for the recalls above can also occur when driving, so (as with so many things in life) the true measure probably lies somewhere in-between. Ultimately, the entire endeavor of comparing vehicle fires by propulsion type involves small sample sizes, limited available statistics, and large error intervals. The only conclusion we can likely draw is that Bolts aren't any more likely than their explodey-liquid brethren to experience a fire. This is comforting, as all such fires are exceedingly rare.
GM's Unique Bolt Recall Guidance
I mentioned the recall guidance for those millions of fossil-fueled vehicles: "park outside, away from structures, until the repairs are complete". Contrast that with GM's parking guidance for Bolt owners:
- "Park vehicles outside immediately after charging"
- "[Don't] leave vehicles charging indoors overnight"
As the owner of a 2020 Bolt, I find this far less onerous than a blanket instruction to park outside until the recall work is done. Mind you, I'm a car guy, and I work hard to keep ours looking sharp. If I can avoid it, I don't want them outside, parked under our giant silver maple trees that routinely shed sticks and branches (and various other detritus) when the breeze picks up. I'd also rather not park any car on our recently paved driveway for too long, creating sunken spots.
Based on GM's guidance, I don't have to worry much about those issues. When we arrive home, we can confidently charge our Bolt in our driveway, and pull it inside after an hour or two. There's no need to keep it outside 24x7, potentially for months (and through a snowy upstate-NY winter) awaiting a service appointment, as we would with one of the recalled non-EVs. Any public opportunity charging we do only further reduces our need to plug in at home.
What Should GM Do Now?
Having to recall an entire vehicle model fleet for any reason is bad for carmakers. When the reason involves EV fire, and the model is an EV, it's worse - for the manufacturer, and for public confidence in EVs. That's only compounded when said automaker has publicly committed to a timeline for full-product-line electrification, and has multiple high-end EVs launching within months.
If GM is truly born-again after the gas-tank ruptures and ignition switch issuues of decades past, and if they're intent on restoring EV enthusiasts' and the car-buying public's trust in their batteries, their only option is radical openness. Vague press releases and generalities that begin with "a defect in..." won't fly this time around, nor will withholding details in the name of trade secrets or competitive pressure. Instead, it's in GM's and everyone else's best interest to:
- Be specific and provide plenty of detail in recall communications.
- Publish open-access technical papers about the LG cell manufacturing process defects and the process of detecting defective cells in-vehicle.
- Publicly explain the details of recall diagnostics and repairs.
- Maintain a frequently updated public dashboard showing the progress of the recall.
- Release any intellectual property related to defect prevention in cell assembly, detection of defective cells, and software mitigations to the public domain - no strings attached - so all automakers can improve their safeguards.
- Publish the software source code for portions of the Bolt's Battery Management System (BMS) and diagnostic tools related to the recall.
As an "alum" of their powertrain engineering division, I realize these are not easy measures for GM's leadership to consider. But I'm also optimistic that the battery team at my former employer are some of the best and brightest in the field, that they'll thoroughly and effectively address the Bolt battery issues, that GM at large will do the right thing for Bolt owners and for EV adoption, and that our family will enjoy many more miles and adventures in our 2020 Bolt.
Bio: Dave Rea is an electronics/software engineer and electric vehicle enthusiast. He developed automotive electronics as part of GM's fuel cell program, helping realize hydrogen-powered hybrid EVs for "Project Driveway". Since 2010, he has designed battery and fuel cell electronics for automotive, airborne, industrial, and stationary uses as a senior partner at AppliedLogix, a Rochester, NY-based engineering services firm. All opinions in this op-ed are solely the author's, are based only on public information, and are independent of current or former employers or clients.