GEM neighborhood electric vehicles are popular means of transportation in many gated communities and even on US military installations. Photo courtesy of GEM.

Behind The Smoke - Part 2

Continuing the investigation of EV fire safety.

By Josh Landess

To Part One

My investigation of the fire that destroyed much of super model Veronica Webb's Keywest, Florida home took me down a path that needed closer scrutiny, namely just how safe are EVs when it comes to recharging them in a residential setting?

To answer my questions, I called a number of experts and current EV owners, starting with Dave Goldstein, President of the Electric Vehicle Association of Greater Washington DC (EVA/DC) and President of Program Development Associates, an independent EV and battery consulting firm in Gaithersburg, MD. He (and others) emphasized several times in our conversations that the facts and the official report was not yet in on this particular fire, and so that while we could discuss general EV safety, and speculate about one single fire that might or might not have been EV-related, we really had to keep that fact in mind.

DG: I think the thing that comes to mind is any time you have an energy transfer, there's always a potential for fire. And that's true whether you're talking about electricity or natural gas or gasoline. There have probably been a great many more fires relating to gasoline fueling than to electric vehicles. With the electric vehicles we have a user history that goes back many decades, if you consider fork lifts and industrial vehicles . .. There have been very few. But occasionally, yes, there have been fire incidents.

EVW: The GEM for example: is this the only one?

DG: I've never heard of another GEM fire. I've heard of occasional golf cart fires. Golf carts are used in golf communities all over the country, all over the world. And occasionally there are golf cart fires.

EVW: Anything relating to high heat and high humidity like they would have had down there?

DG: The only thing that comes to mind is a similar situation that occurred inside a garage in the UK on a very hot humid summertime evening a couple of decades ago. It put an end to the Lucas Electric Taxi Cab program in the UK back in the 1970s. They had a very attractive electric taxi cab, with styling by Pininfarina. What they did was they put them up on lifts and replaced the battery packs and also charged them while they were on the lifts near the garage ceiling.

And on this one particular hot August evening in the UK, there was a fire that actually destroyed the garage and several of the vehicles. And that ended the entire electric taxi cab program. The cause was believed to have been a buildup of hydrogen gas. Of course this is a potential hazard with almost all batteries, particularly flooded lead-acid batteries, which must gas in order to fully charge. So proper ventilation is absolutely essential. That's the most common thread, the most important thread for EV safety when you're charging batteries. Batteries should never be charged in an enclosed garage without adequate ventilation. Especially in warm weather which increases this effect. I don't think many private owners really realize this.

EVW: Then I've got to get that information out there.

DG: Absolutely. It is important to remind people that when you charge a battery, at a certain point, you're going to get some bubbling in the battery that helps stir up the electrolyte. And that's part of the design, to have a certain amount of gassing or overcharging. And that hydrogen gas can build up and accumulate and create a fire hazard or even an explosion hazard. And this has been known for decades, more than a century. I mean there's no mystery to this.

But another important point to keep in mind is that in golf cart type vehicles and in many converted EV'S, you have flooded batteries which require periodic watering, at least once every four to six weeks. If you fail to do this, then you will have even *more* hydrogen gas buildup than you would otherwise. So you must do periodic maintenance and you must charge the batteries in a well-ventilated area. And even with so-called "sealed" batteries which never require watering, there can still be some hydrogen gas during charging, so proper ventilation is essential.

EVW: And yet, if we're inviting dozens of millions of people to start owning electric vehicles that have never owned them before, they may not know it. It may not be common knowledge to them.

DG: That's true.

EVW: I have to admit I have yet to read the owner's manual on the regular car that I drive. Keeping in mind that we do want to hold owners responsible for reading the manual, I also want to take into account, with human behavior being what it is, that some of them won't read it.

DG: So what can we do to make it right? Well, I think first of all that we need more information about what happened in this GEM incident.

EVW: If I owned a GEM, it's possible I might not read the manual. I'm just not a very good read-the-manual-person.

DG: Well, that could be. And you would be potentially liable if something like that happened for failing to take the proper safety precautions. I don't think if you were to sue DaimlerChrysler for example that you'd get very far in a situation like that. But I think we're talking about prevention here. And I also think we're talking about this in the context of the fact that there's very little evidence that there is a significant problem. What we have here is an isolated incident that was blown up in a newspaper because it involved a celebrity. I've been involved with EV'S for some 25 years, and I am aware of fewer than a dozen EV fires

Although the GM EV1 is one of the best cars I've ever driven, it was not meant to be a full-on production model, and a design flaw that only appeared after extensive use, did lead to at least one fire and possibly two or three other "unconfirmed incidents," including melted or warped charging paddles . . . A limited recall of the Gen 1's and S-10 electric pickups seems to have fixed the problem.

EVW: Have there been any incidents like this in later model EV1's or any other EV'S that use inductive charging?

DG: No, none that I am aware of. The Gen 1 problem was traced to a capacitor that basically aged over time and heated up. Later models had a slightly different design and were not affected. And there have been no problems thus far in inductively-charged EV'S from Toyota and Nissan.

EVW: So it was not necessarily inherent to inductive charging.

DG: No not at all. It was just something that showed up over time as the equipment aged in a specific model. It was something you learn with experience.

Home Wiring Issues

EVW: There are several different things going on here. You're refueling at home. So if something goes awry, you're not only endangering one person's life who's refueling, but you're endangering the whole home and the family in that home. Over the next few years, we might hit a point where all of a sudden the attention of the nation is focused a bit more on whether EV'S offer a real alternative. We may have an issue for example, when chargers are installed, are they installed properly? Does it bring out deficiencies in a house's wiring that weren't apparent before? Is there an issue of an operator and owner making bad mistakes? If they make more mistakes than anticipated by the manufacturers, should we worry about blaming them or improve the vehicle and charging process so they are less vulnerable to these mistakes?

DG: We can do things to make vehicles less prone to owner error, more user friendly. But the owner has to bear a responsibility. Anytime you're drawing high current, whether it's a toaster, a space heater, or an electric vehicle charger, you must have proper wiring and you must have proper outlets. And they have to meet certain safety standards. If you're dealing with a house, let's say for example, that has aluminum wiring, which happens in houses . . . I don't know what the situation is in particular houses in Florida, but there have been many cases, for example, where aluminum wiring, over a period of time has developed oxidation in the connections and fires have occurred, particularly in outlets where high currents were drawn. For example, like from a clothes iron, or a space heater. Any type of high current device certainly puts a stress on a weak house connection. So there's always a possibility that there may be an issue in the house itself that only comes out over time and with high current demands. So it is incumbent upon the owner, their electrician, and the company that is selling the product to advise the owner to be sure that their electrical outlets are properly designed to handle a high current. And it's probably a good idea to have safety precautions in the owners manual, if the owner reads the owner's manual.

EVW: Are there adequate safety standards?

DG: There are both national (NEC) and local housing code standards for both the electrical connectors and for the house wiring. Different standards (generally UL and NHTSA) apply to the vehicle itself and to the equipment on board. In golf cart type vehicle like the GEM, the charger itself is typically on-board. In the case of the inductive charger, most of the charging equipment is off-board. So different standards may apply in each instance. EVW: Most conductive charging is on-board?

DG: Yes. So there's a difference here, and the wire in the charger, generally has to meet UL safety standards. Okay so we're presuming here and I don't know this for a fact, that the chargers in the GEM vehicles meet UL safety standards. I would be very surprised if Daimler Chrysler had installed a charger that didn't meet UL safety standards. I'm sure somebody from Daimler can confirm that.

So there is the issue of the charger itself. And again we don't know where the actual problem happened. It's also possible that a battery connection might have been weak. There have been incidents where loose battery connectors caused high resistance that heated up and, under the right conditions, could have caused a fire. So we know that there's a potential battery connector issue that also relates to having regular maintenance done.

DG: Let's get back to safety. Most of the major automobile manufacturers, including DaimlerChrysler, have been directly involved in the development of safety standards for EV'S, chargers and connectors. They don't want to see fire or safety issues occur with their products any more than we do as customers. And although, it has largely been unsaid, they would like their EV products to be as foolproof, some would say, "idiot proof," as possible. Unfortunately, nothing is 100 percent. The customer does bear some responsibility, but proper education is also very important, especially for those who fail to read their owner's manual or forget to observe the safety warnings.

When it comes down to the big picture on safety, I don't think we see a significant problem either in crash safety or fire safety with electric vehicles or with industrial vehicles, with golf carts, NEV'S or any of these. It's just that the only reason the press calls attention to them is basically that they represent an unusual story. When a celebrity gets involved, it becomes even more fascinating.

EVW: Well, I'll play devil's advocate here: Even if (and we don't know this) she or he, the husband, was not operating the vehicle properly, the bigger lesson here is to learn from that. And to realize that it's going to happen again....

DG: I would speculate that it won't happen a lot but it will happen in limited numbers. There is more that we can do to educate the public about EV safety and we should and we must. And that's kind of fallen between the cracks. That's one of the things we really haven't said here. It's fallen between the cracks.

There was, some years ago, a joint EV safety effort with DOE, the National Renewable Energy Laboratory (NREL), DOT, major OEMs and various EV organizations, including EVAA and EVA/DC, to review safety standards and to develop educational programs, not only for the public, but for fire and safety organizations. But all of that has gone by the wayside. The budget for that is gone. There is no more safety education effort that I can see . . . Some of that is being done by the individual manufacturers, but not all of them.

About eight years ago we had a very nice little safety program put together. Books and pamphlets and videos about the five or six different EV'S that were available at that time. And it was done with the blessings of the manufacturers who didn't want to assume the responsibility for safety issues. They wanted the government to get involved. And once the electric vehicle thing started to go south and the emphasis shifted to hybrids, they didn't want to get involved with the government anymore. It's just the way it was. So right now there is no unified effort that I'm aware of, dealing with EV and battery safety education.

EVW: Next I spoke with Jim Motavalli, the Editor of E/The Environmental Magazine, pointed out to me that the Ford Ecostar EV program, powered by Sodium Sulfur Batteries, which operated at high temperature, was discontinued perhaps due to concern over a couple of fires that happened. He also was one of a few EV enthusiasts who seemed able to relate a personal anecdote of a fire or near-fire that occurred while charging an EV (sometimes a home-made EV, sometimes not). He also emphasized the importance of using a Ground Fault Interrupter (GFI), an opinion echoed by many. It is recommended (p. 29) by the GEM manual.

EVW: I also spoke with Phil Karn, an engineer who has preserved on the web a record of a Generation-1 GM EV1 fire, and documented GM's recall and fix of the vehicle. Despite having personally witnessed the damage left by the fire, Phil waited while GM put a fix into place and is, once again, a satisfied EV1 leaser. He, like many other satisfied leasers, is upset that GM is refusing to renew all leases, apparently will not sell the car including the battery pack to anyone for any price, will be taking all cars back by the end of this year, and, it is feared, will be destroying them. About 900 EV1's were put on the road.

This is what he had to say:

PK: EV safety has concerned me ever since that EV1 fire here in San Diego. It happened to a colleague at Qualcomm, and standing in her burned-out garage I couldn't help but think how easily it could have happened to me.

Back in the mid 1990s when the EV1 (and Honda EV+) were released, GM made a big deal about the safety of inductive charging. They all but pronounced it intrinsically safe.

We now know better, of course. The GM ad campaign focused on electric shock, but that's not the only potential hazard in EV charging, nor is it even the most important one. And no system that routinely handles several kilowatts of electricity in your house is ever "intrinsically" safe.

But nor is EV charging intrinsically unsafe either. With proper care and attention to detail, it can be made very safe in practice, probably much more so than gasoline. In the early days of the automotive age, gasoline cars routinely burned up too. But engineers learned lessons from these accidents and made safety improvements that vastly reduced the incidence of car fires. But they still happen, albeit rarely.

Even before the EV1 fires, I thought the safety bodies considering EV charging standards placed too much emphasis on electric shock and not nearly enough on fire. But thanks to modern electrical wiring practices and the GFI [Ground Fault Interrupter], accidental electrocutions are now extremely rare. They are far less common than deaths in structure fires started by faulty electrical wiring or equipment.

I think we need new protective devices specifically designed to prevent electrical fires in the same way the GFI was specifically designed to prevent electrocutions.

The device I have in mind is actually quite analogous to the GFI. The GFI looks for tiny current imbalances in the hot and neutral wires of an appliance that might indicate a stray path to ground through the body of a victim. When such an imbalance is detected, the GFI trips.

I envision a "power fault interrupter", a device that measures power flows at different points in the EV charging path to ensure that undue amounts aren't being lost as heat that could start a fire....

I am quite confident that GM has eliminated the specific cause of the EV1 fire I saw. When it happened in Feb. 2000, the failed component (a capacitor in the charge port) had *already* been removed from the Gen 2 charge port used in the 1999 EV1. I've not heard of any more incidents with the EV1. I'm reasonably sure I would have, had there been any.

Given GM's touting of the inherent safety of inductive charging, it's indeed ironic that it failed in a way that the Avcon conductive plug/receptacle could not because the Avcon lacks the capacitor that exploded in the Gen 1 EV1. The conductive plug and receptacle also dissipates far less heat in normal operation. (The inductive coupler is so inefficient that it has to be actively cooled by the car's liquid cooling system. I personally find this rather offensive, and reason enough to dump inductive charging.)

To be sure, I can conceive of safety failures in the Avcon conductive charging design as well, but I have not heard of any fires. My proposed "power fault detector" would easily guard against these possible failures. (The GEM uses a standard extension cord, not the Avcon plug, and in any event we do not yet really know exactly what happened in that GEM fire.)

As you might know, last year the California Air Resources Board (CARB) voted to establish the Avcon conductive plug as the standard, over the strong objections of GM and Toyota. I filed comments in favor of CARB's decision, and I think they did the right thing. The decision won't actually take effect for some time, though.

GM cites this ruling as contributing to their decision to pull the EV1 from the market.

Isolated EV Fires

Although official statisticians I consulted did not tell of any recent fires in the production model Neighborhood Electric Vehicles, we can see that there is such a thing as an EV fire or a near-fire, though the frequency with which such incidents occur is an open question to me.

My inability to find any recent examples (at all) of fires in the increasingly ubiquitous GEMs or Ford Th!nks left me wondering if the only stories of EV fires or near-fires would be among the more hard-core enthusiasts.

I'd like to provide the reader with a couple of examples of anecdotes one can find by asking around, not to be sensationalist, but they at least provide a better picture of these apparently relatively rare incidents:

"I never heard of a fire involving a NEV. The only fire I have heard of was ....using Powercheqs on a Sparrow. The member posted photos. I believe Powercheq may have paid for some or all of his damages. The Sparrow is not a NEV. Powercheq is an aftermarket device which I believe is being redesigned....."

[name withheld], 1998 Bombardier owner

"I'd like to describe an incident involving an electric truck (either Talor-Dunn or Nordskog, a small NEV-like utility vehicle) that happened at my work. The vehicle was in the shop for repair, and the batteries were being charged with the truck bed removed (exposing the batteries) A mechanic began using an air grinder on some welding he had done on the truck, and when the sparks landed on the batteries - BANG!, there was a very loud pop and one of the batteries exploded. However, there was no fire afterwards. This was probably caused by hydrogen gas. It seems that a this gas burns in a rapid flash, not a raging inferno, like the Hindenberg. There are also warning labels I've seen around these vehicles or batteries saying things like " charge in well ventilated area, don't smoke near batteries, etc." At the time we were using vented 6 volt batteries, these vehicles have now been converted over to sealed Optimas."

The editor of Electrifyingtimes.com, Remy C., commented:

"I'm in the EV biz. I know that if such fires were happening "often" we would have heard about them by now... They happen in EV racing where components are pushed to the limit, but not with NEV'S. Thousands of these safely service theme parks, gated communities, etc... if this was an epidemic, it would be all over the news."

One well-known Electric Vehicle activist remarked in a public discussion forum that "two or three million" off-road electric vehicles such as golf carts and electric forklifts exist in our society without controversy, recharging with few if any mishaps. I found no fire data for such established lines of electric vehicles.


Times Article Viewed: 7960
Published: 11-Aug-2002


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