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Battery Fires and Range Fury – EV Battery Recalls

Chevy Bolt Battery Photo by Jeffery Sauger for General Motors, April 5, 2016

We bought our 2018 Chevy Bolt in 2018, feeling assured the 238-mile range advertised for the vehicle would meet our daily needs and make our most common weekend trips. Knowing Electrify America was making steady progress on installing DC fast chargers on interstates from coast-to-coast, we figured the Bolt would also allow cross-country trips on the rarer occasions we needed to make them.

Battery and Range – What You Expect

Therefore, our decision to buy the car was based on two things: the size of the battery and how the battery management system (BMS) functioned.

  • The size of the battery determines the maximum distance you can travel between charging stops.
    • For the Bolt, that distance is about 238 miles in mild weather, with no extremes of cold or hot temperatures.
  • The BMS determines (among other things) how often you can use a DC fast charger each day and during periods of high or low temperatures.
    • The Bolt’s BMS includes a liquid cooling system. When you use a DC fast charger to add electricity to your car’s battery, the battery’s temperature increases. The liquid cooling cools the battery quickly enough it can accept another full charge by the time you need one. You can DC fast charge multiple times a day, regardless of the outdoor temperature.
    • In contrast, the 2018 Nissan Leaf used only air cooling. It could not cool the battery fast enough to allow more than one fast charge a day on a hot summer day. So range is significantly limited on hot summer days.

What Chevy Bolt, Kona Electric and Ioniq Electric Owners Got

Our Chevy Bolt Story

On November 13, 2020, six weeks after we returned from our 3,200 mile round-trip road trip from Durango, CO to the top of Michigan’s mitten, Chevy recalled our Bolt due to concerns about the battery catching fire.

Chevy recalled a “select number” of 2017-2019 Chevy Bolts built with:

“high voltage batteries produced at LG Chem’s Ochang, Korea facility that may pose a risk of fire when charged to full or very close to full, capacity. As an interim remedy, dealers will reprogram the hybrid propulsion control module 2 (HPCM2) to limit full charge to 90%.”

https://my.chevrolet.com/how-to-support/safety/boltevrecall

We had DC fast charged four or five times a day for each of the 3 days of the trip both coming and going. At several of those charging stops, we’d had to charge to greater than 90% so we could get to the next DC fast charger with some cushion.

No one wants to consider being trapped in their car, trying to slow down from highway speeds so you can bail out because your car is on fire. (Know that fires are far more likely in petrol-powered cars than EVs.) If we’d had to stop more frequently, what was already a really long trip due to charging stops would’ve been even longer.

Chevy’s interim fix is a BMS modification. We got the car reprogrammed right away, and as of 3/2/21, we’re still waiting to hear what the final fix will be.

Two things every EV owner should be aware of when it comes to battery-related recalls:

The federal National Highway Traffic Safety Administration (NHTSA) initiates recalls for SAFETY reasons.

A recall is issued when a manufacturer or NHTSA determines that a vehicle, equipment, car seat, or tire creates an unreasonable safety risk or fails to meet minimum safety standards.

https://www.nhtsa.gov/recalls
  1. In other words, under federal law, there is no protection for EV owners if a safety fix causes a reduction in vehicle range.
  2. If Chevy proves limiting the charge capacity to 90% fixes the safety issue, the NHTSA recall can be closed if that limit is made permanent by the BMS software. Owners would have to band together and sue based on the loss in value of the car due its reduced range. It seems unlikely that after the lawyers were paid there would be much left for those of us still owning these vehicles.

Finding Fault: Battery Manufacturer or Car (BMS) Maker?

Chevy Bolt Not Alone with Battery Fires

The cause for the fire hazard in the Chevy Bolt is not yet settled. The Hyundai Kona Electric and Ioniq Electric are also on recall for battery fires right now, with batteries also manufactured by LG Energy Solutions, though at a Chinese facility.

  • Hyundai has claimed the fires were caused by defective manufacturing (a misalignment of an anode tab) of some battery cells on LG’s part.
  • GM (Chevrolet) has stressed the Bolts’ batteries use a different cell separator than Hyundai and so the two recalls are unrelated.

On 2/24/21, LG stepped into the fray. In a statement on the Kona EV recall, LG states the Korean agency responsible for confirming the cause of the fires has not been able to confirm the problem is misalignment of the anode tab. They claim Hyundai misapplied the BMS fast charging logic proposed by LG. They are cooperating with the “relevant authorities” to discover if that had any connection to the fires. LG also says damage to the batteries’ cell separators has been confirmed as unrelated to the fires by a joint investigation team.

So, for Chevy and Hyundai, and Bolt, Kona and Ioniq owners, the question is: Do the batteries need to be replaced or is it a BMS software fix?

Hyundai has had more fires in their affected vehicles and their recall covers a larger number of vehicles. Rumors are circulating that for Hyundai, all battery packs may need to be replaced. Kona Electric owners are suing for depreciation the issue has caused. Chevy owners haven’t organized on that front yet, but I would not try to sell or trade in our Bolt until this issue is resolved. I think most buyers would hesitate to buy a Bolt affected by this recall.

How do you Fix it? What Chevy Says

I called the Chevy EV concierge on 2/27/21 after reading the following on Chevy’s Bolt Recall webpage:

A team of GM engineers has made substantial progress in identifying the root cause and potential remedies for this issue. They are in the process of validating state-of-the-art software that can diagnose potential issues early and restore 100% charge capability. A final remedy for this recall is anticipated for April 2021. Until that time, if you have not already done so, we recommend scheduling a service appointment with your dealership to update the vehicle’s battery software to automatically limit the maximum state of charge to 90 percent.

https://my.chevrolet.com/how-to-support/safety/boltevrecall

I asked the concierge how a software fix (a BMS fix) would solve the problem. Would it detect changes within the battery and provide a warning to the owner if changes occurred which might lead to a fire? Then the battery could be repaired or replaced before a fire could happen?

The concierge said it has not yet been determined the final fix will be software. He said it hadn’t gotten to the point of even discussing if a warning system would used or required. They don’t yet know if it will be a software fix or a battery replacement. We might find out earlier what the fix will be, but the fix won’t actually be available until April 2021.

It seems GM appreciates the importance of maintaining the range promised to buyers at the time the vehicle was purchased. A ten percent range reduction may not sound like much to a judge behind a bench, but when you’re sitting in the dark, gravel parking lot in front of the I-70 diner in Flager, CO at 11 PM, hanging in there for yet another 20 minutes to be sure you make it to your motel in Colorado Springs two hours away, it seems like an awful lot indeed. GM would do well to keep their EV early adopters in mind as they plan for their all electric future. I hope they won’t leave us furious with the cure to this recall, whether it be for the battery or the BMS.

For good, in-depth reporting on this issue, check in at InsideEVs.com where reporter Gustavo Henrique Ruffo has been following the issue closely.

Also see: https://aju.news/en/kona-recall-was-decided-but-hyundai-motor-lg-inevitable-conflict-over-responsibility-and-cost.html

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But I’ve heard that EVs don’t do as well in cold weather…

But I’ve heard that EVs don’t do as well in cold weather…
Chevy Bolt on a cold Canadian ski trip

They don’t, but neither does your internal combustion engine (ICE) car, and no one whines about their ICE car in the winter (if it starts). All vehicles lose some efficiency when they are cold, but alert reader Richard Grossman pointed out a recent article (link: https://insideclimatenews.org/news/11022021/inside-clean-energy-norway-electric-vehicles/) on Norway’s adoption of EVs: 56% of new car sales, compared to 2% in the United States. This fact was highlighted in a recent Superbowl ad for Chevrolet, but remember this: the top FIVE countries for EVs sales are all near the Arctic Circle:

  1. Norway 56%
  2. Iceland 23%
  3. Netherlands 15%
  4. Sweden 11%
  5. Finland 7%

The linked article explores the reasons for Norway’s rapid adoption of EVs, which include celebrity endorsements, an early and rapid government-funded build-out of charging stations, and tax breaks that provide purchase price parity between regular cars and EVs. If you are interested in EV policy incentives, be sure to check out the lively article by Dan Gearino in the link above.

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Battery Best Practices

by Sarah Kelly 1 Comment

When I got my first EV (2017 Nissan Leaf), I gathered from various sources there were things you should do and things you should avoid to extend your car’s battery life. Batteries make up about 35% of the cost of an EV, so you want to make them last. However, the owner’s manual was light on advice and the internet was full of conflicting information about what was important.

Nissan Leaf cutaway showing part of battery
By Tennen-Gas – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8249799

An EV-savvy friend told me the simplest rule was to keep your battery between 10% and 90%, and don’t let it sit at 100% charge for long time periods. When you fill it to the top, start drawing it down soon. That is good advice, but I like to know WHY a thing is important and WHO says so.

Finally, University of Michigan researchers have studied the issue and came up with some easy to understand best practices. Why should we care about treating our EV batteries right?

Battery degradation causes premature replacement or product retirement, resulting in environmental burdens from producing and processing new battery materials, as well as early end-of-life burdens.

Center for Sustainable Systems, School for Environment and Sustainability, University of Michigan researchers

Below are eight best practices as summarized by the Electrek.co article cited in the quote below. Follow the link to the article to learn more about the study.

Here are the 8 recommendations that we summarized from the paper. We note which brand of vehicle provided the guidance in its owner’s manual.

Journal of Energy Storage studies EV owner’s manuals, compiles best practices for batteries
  • Every manufacturer includes a warning about high temperatures, though different strategies are suggested. Most companies do not cite a specific high temperature in which to avoid vehicle operation. Those that mention a specific temperature use either 50° C / 122° F [Fiat-Chrysler] or 60 °C / 140° F [Tesla].
  • Plug in the car anytime it is hot, thereby allowing the battery cooling system to run as needed [Tesla and GM].
  • Avoid parking in the sun on hot days [Kia]. When the vehicle is plugged in, the BMS (battery management system) will measure the temperature and take the appropriate warming or cooling action before charging begins [Tesla, Ford, GM, Nissan, Honda], and may disable fast charging capabilities [Kia]. The researchers advise: When the vehicle is running or charging, the BMS will regulate the temperature of the batteries, so it is most important to be aware of high battery temperatures when the vehicle is parked while not charging.
  • Dealing with low temperatures is also cited by almost all EV owner’s manuals. Plugging in the vehicle when it is cold (below 0° C / 32° F) is recommended so that the battery heating system can run on grid power. The battery warmer will automatically activate below a specific temperature unless the battery is both not plugged in and under 15% charge (to avoid over-discharge) [Nissan].
  • Extremely low temperatures for extended periods may cause irreversible damage, necessitating battery replacement [Mercedes-Benz]. The lower temperature limit for batteries is cited as −25° C / -13° F [Nissan, Mercedes-Benz] or −30° C / -22° F [Tesla, Honda].
  • Over-discharging will typically not occur during operation. The BMS will turn off the car and cease operation before severe degradation occurs. However, if the “empty” battery is then left for an extended time without being recharged, the battery can enter an over-discharge state due to the slow self-discharge that occurs even when the battery is not operating. Some manufacturers are concrete, instructing owners not to leave the vehicle parked for more than 2 weeks with a low battery (20% state of charge) [Tesla, Mercedes-Benz].
  • If possible, don’t allow the battery to be run all the way down, or left idle for extended periods [BMW, Hyundai, Kia, and Honda].
  • The majority of manufacturers do not include information in their manuals explaining that fast charging can lead to accelerated battery degradation. Those that say use of fast chargers should be minimized to maintain battery life [Ford, Nissan, Kia, Honda].
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