The Folly of the 300 Mile Battery Electric Vehicle

There is a common misconception that the goal of the Battery Electric Vehicle is a that of a range of 300 miles. People expect 300 miles because they are used to it. The problem is that BEVs are a different type of transportation tool from conventional gas vehicles and should be used in different ways.

Let’s start with refueling a gasoline powered vehicle. It’s a pain. You have to take time out of your day to go to a stinky gas station and pay a substantial fee for the privilege. No one enjoys this, which makes a gas car with an extended range a benefit. A car with a large tank that gives you a 600 mile range will cut your trips to the gas station in half compared to the 300 mile range tank. Electric vehicles, in contrast, aren’t refueled at gas stations. They are recharged where they are parked. Plugging in a vehicle at home or at work is a minor inconvenience compared to going to a gas station, and one that people are well accustomed to due to their experiences with rechargeable devices. Since cars generally spend most of the time parked recharging ought to be inconsequential for most people.

The average distance traveled by most vehicles on any day is under 40 miles. Adding a 100% safety cushion to that 40 miles will cover most daily trip chains, which gives us the 80-100 mile range of BEVs like the Nissan Leaf. Given that a Leaf’s range works for the driver 95% of the time, the Leaf’s lack of refueling trips would be a net benefit for the driver. The car just keeps going.

Now let’s extend that Leaf into a 300 mile range BEV. What happens first is that the cost of the vehicle increases dramatically. Let’s say the cost of the Leaf’s battery is about $7000 (45 kwh @ ~ $150/kwh – a very conservative guess, the reality is certainly higher). Tripling the range of the vehicle entails tripling the size of the battery. The cost of the battery is now more than $20,000. This will push the cost of the vehicle up into a much higher vehicle category, the vehicle would likely have a minimum sticker price in the mid-40,000 range rather than the high 20’s. The larger battery also increases the weight of the vehicle by at least a couple hundred pounds, which makes it somewhat less efficient, but that itself is not a major problem.

But now the owner can drive 300 miles without a recharge, great! Right? Maybe. Consider that a standard Leaf takes about 7 hours to recharge at 240V / 40 Amps, a washer/dryer level line. Triple the size of the battery and you triple the full recharge time to 21 hours. That means if you run that 300 mile Leaf out for its full range you need almost an entire day to recharge it at home. That implies the vehicle cannot be used like a conventionally fueled vehicle for repeated high mileage trips, although the vehicle can still be driven without a complete charge. But if the driver is not going to use the last 20 kwh of battery on any sort of regular basis why pay the $3000+ (20 kwh * $150 kwh, optimistic scenario )to put it in the vehicle?

What people really want when they say they want a 300 mile range BEV is a long-range electric drive, zero emission vehicle, that can be easily refueled. Better Place’s battery swapping system is one approach, but perhaps the desire for such a vehicle is best met by a Hydrogen Fuel Cell Vehicle (HFCV)? While not quite as efficient as BEV, an HFCV offers many of the advantages of the BEV without the recharging problem. As long as there are fuel stations on the route the HFCV can be driven just like a conventional vehicle. The HFCV can also be built for less money than a BEV since they don’t contain a large, expensive battery. In fact it is projected that HFCVs can approach the cost of conventional gas vehicles.

The gas car is an amazingly powerful and effective tool for personal transportation. Attempting to duplicate its utility with an electric vehicle is not going to work. Instead, it’s better to think about the electric vehicle in terms of what it can do well and efficiently and use it for that. Vehicles like the Leaf with its sub-100 mile range can make a lot of sense for daily driving. Long distance driving as we are used to with gas cars doesn’t work so well for electric vehicles. Rather than stretching the BEV to do something it isn’t meant to do, why not find a way to pair BEVs with access to other vehicle types that can easily manage long trips? That’s where we’re heading.

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6 thoughts on “The Folly of the 300 Mile Battery Electric Vehicle

  1. The Nissan Leaf does not have 1 45 kwh battery. It’s more like 21 or 24, depending on whether you consider only the “usable” capacity.

  2. I agree with the premise of this article, but there are a number of factual errors:
    -The Leaf battery weighs about 600 lbs. Tripling the size of this is not a minor problem (though the top Model S has done so with size and energy density).
    -The current Leaf charger only runs at 3.3 kW, drawing up to 16A, not the 40A the wall circuit may be rated for. A larger battery pack will certainly receive a higher rate charger which may make this point a non-issue. (The Model S can charge at up to 20 kW, again, for a price).
    -The Leaf can charge at up to 50 kW on its current DC Fast Charge port, and when these chargers proliferate that will make the 300 mile battery that much more unnecessary.
    -Large packs can help one thing: current draw per cell from high output motors (again, like the Model S performance model).

    • Bill,

      Thanks for the comment. I should clarify that that I am using predictions of what can be attained
      in battery technology in the future from Kromer and Heywood (“Electric Powertrains: Opportunities and
      Challenges in the U.S. Light-Duty Vehicle Fleet”). In fact, my first draft of this essay argued
      the weight issue was another strike against the 300 mile BEV, but K&H say it’s probably not an
      insurmountable problem given the development of advanced battery technology (pg. 41). My Leaf comparisons
      were included to give a tangible example of what a 300 mile BEV would mean, using a very conservative
      case, although the 45 kwh battery is high. That number comes from ANL/DOE’s “Multi-Path Transportation
      Futures Study: Vehicle Characterization,” another forward looking study.

      -“Large packs can help one thing: current draw per cell from high output motors (again, like the Model S performance model).”

      Most definitely. Large battery packs are mostly a luxury feature. Operating a BEV at high speed with multiple
      fast accelerations kills batteries. BEV sports cars will need large batteries if they are to be used as
      intended. The purpose of the 300 mile battery (rated at 55 mph) on the Tesla S (an option) is for entertainment, not for range.

      Best,
      Joel

      • “The purpose of the 300 mile battery (rated at 55 mph) on the Tesla S (an option) is for entertainment, not for range.”

        Entertaining it sure as hell is! 😉
        Thanks for the clarifications.
        -Bill

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