What Happens When An EV Runs Out Of Juice?

73 thoughts on “What Happens When An EV Runs Out Of Juice?”

• The Leaf can be set up to send a text message if you forget to plug in at home. It works well on my 2013 model.

  • With Carwings…

    • That’s the name of the product Nissan have established to do what you suggest should occur. I’m not sure what your response was implying. I’ve been reminded several times over the last 4 1/2 years when I forgot to plug-in.

      • Just stating that to have what seems like base functionality, a special product is required. My Leaf S doesn’t have it so I’m out of luck 🙁

  • Exactly. There should be no reason to ever have this happen. Our Focus Electric will send us a text if it thinks it should be plugged in when it’s not. Since the Fords come with location based charging, we can get these alerts at any location where we have charged previously & saved.

    Yet another area where Nissan’s design is a failure. I’m very disappointed in how many features are missing from the Leaf.

• How about a range extender trailer? I think the ultimate setup would employ the use of a photovoltaic array, an EV, and a range extender trailer that doubled as a home energy storage system. Tesla should put some wheels on a redesigned Powerwall and add some quick-connect ports for easy transfer between house and car.

  • Those Powerwalls only have 7 or 10kWh of energy storage. That could be a godsend if you were stuck but mostly that is not enough to make it worthwhile to build a wheelable unit. I guess you would need to add an inverter to turn it into a level 2 AC charger too since the DC voltage would be too low to feed directly into my EV at least.

    • imho, long range EVs are too close to work on solutions this complex. The ultimate fix for range is long range EVs…then go back and upgrade these range limited EVs…

      • The problem is that some companies (*cough* Nissan *cough*) refuse to upgrade batteries. So it may make sense to invent third-party range extenders. Something that fits flat in the trunk might make the most sense. Hooking it up is the real challenge.

        • Any company that refuses to upgrade or adapt… will become obsolete…and pretty quickly…see Kodak

        • To be fair to Kodak they did attempt to adapt and made a line of digital cameras. They failed, but at least they tried.

          The thing that boggles my mind is that Nissan were innovative enough to make a huge commitment to EV’s by introducing the LEAF in 2010, but then the follow through has been below par. Nissan are now reacting to other OEM’s such as BMW rather than lead them. Nissan gave themselves a head start and now find themselves trailing. Weird.

        • Kodak invented the digital camera… The problem was that film was too much of a money maker for them so they did everything they could to suppress it, instead of leading the way because of greed, shortsightedness, and inept leadership…. Digital was coming whether Kodak (the 800lb gorilla) wanted it to or not, but instead of leading as they had a huge head-start, the brand, and the capital to lead, they eventually followed, but it was too late, and as a result they went bankrupt. No company is too big to fall from it’s perch if they fail to adjust, adapt, continue to innovate, and most importantly to give the consumer what they demand.

        • I wonder if in 20 years we could replace the name Kodak with Nissan to tell the same story?

          I’m currently reading The Master Switch by Tim Wu which examines a similar tale of companies rising and falling. The books focus is on monopolies in information empires, but the parallels to the car/oil industry are there.

        • Toyota.

          Nissan, I think, will be strongly in the game. They just need LG Chem to start pumping out the less expensive batteries.

        • No, Kodak got in early. They made the first digital SLR (based on a Nikon SLR body sort of like Tesla making their Roadster on a Lotus sled). And Kodak made some decent compact digitals (or had them manufactured under their brand name).

          But Kodak failed to follow through. Other manufacturers developed digital cameras faster. Kodak seemed to treat their compacts something like one use film cameras. Their first models were good enough for casual shooters. Other companies were working toward film replacements and kept pushing the technology further.

          Canon grabbed the dSLR market and forced others like Nikon to rush and keep up. Kodak never bothered to take their initial very good dSLR and compete in the market with other companies.

          It’s kind of like Toyota and their Rav4 EV. Great first move. Then they put the ball down and went home.

          Nissan, I think, has been battery crippled. They tried manufacturing on their own, building a couple of battery plants. But they didn’t seem to have the battery specialists to make an advanced battery, or make battery advancements. They (IIRC) turned to LG Chem to supply their batteries.
          LG Chem seems to have gotten serious about EV batteries. About the time Panasonic/Tesla is able to produce batteries for 500,000 EVs a year LG should be able to produce 450,000.

          I’m guessing that LG will keep up (possibly surpass?) Panasonic so Nissan should be able to get into the game with a lot more vigor than over the last couple of years. Remember, GM spilled the beans and reported that they will be getting their batteries from LG for $145/kWh, close to what is speculated for Tesla.

          I’ll bet that if Ghosen continues to run Nissan (and Renault) that Nissan and Tesla will be the numbers one and two EV manufacturers five years from now.

          At least the numbers one and two outside of China.

        • Its interesting to speculate that if Nissan outsource their batteries to LG and at the same time Tesla bring manufacturing in house, they will have partly swapped battery strategies 🙂

          I believe Nissan made the right overall call to own both the EV and Battery factories, but as you point out they failed in execution producing a sub par battery.

          Hopefully Nissan will assemble the LG batteries in their factories under LG license. Be nice to keep those jobs here in Tennessee.

          Nissan will have to double down, they’ve lost their early lead and are at risk of falling behind. Another blunder and they will fall behind. I’d like to share your optimism, but Nissan will have to prove to me their mettle before I change my outlook. 5 years have gone by and there is still only one BEV available in the US from Nissan. They are moving waaay toooo sloooow.

        • I doubt that Tesla could have started their own battery manufacturing company and produced an advanced battery. Their approach of partnering up with a major battery company moves them right to the top in terms of battery technology.

          I think the Smyrna factory is being used/will be used for LG batteries.

          I don’t think Nissan is in any sort of trouble. They’re simply coming at EVs from the low(ish) end while Tesla is coming from the high end. Nissan has the ability to produce far more EVs per year than Tesla. If Tesla produces an EV with 125 to 150 solid miles with a price close to $25k I think they could easily outsell Tesla in terms of numbers.

          2016 is apparently the year of the affordable batteries. GM has leaked the $145/kWh price from LG Chem. Surely Nissan will get the same or better price (higher volume purchases). 2017 model lines could be very interesting. if Nissan introduces a sedan and crossover version with good range for about $10k less than the Bolt and the Mod3 then they could sell like hotcakes.

          Oh, and make them more attractive than the Leaf.

        • Well I hope you’re right.

          As I add things up in my mind maybe Nissan have already fallen behind.

          5 Years and Nissan have one EV, the LEAF; it has been upgraded. Nice to see two battery options.

          GM Have two models (Volt/ELR) and launch the Bolt next year as a third model. Volt Upgraded as well.

          Tesla have two models (S/X) (Three if you count the roadster). They offer multiple battery sizes and are upgrading the Roadster in a major way.

          Late to the party BMW already have two models (i3/i8). i3 to be upgraded.

          Nissan really need to hurry up and get busy.

    • They are pretty compact. If 10kWh wasn’t enough, put a second or third unit on the trailer.

      There would also need to be some engineering to connect the trailer to the cars wiring as a supplement to the onboard battery pack. Connecting to the J1772 port wouldn’t work, EV’s won’t charge when turned on and won’t turn off when charging.

      • How about when you start the EV, the trailer could turn from a solar panel to putting up a wind turbine. When you pull it behind, you get to make electricity, right?

        • You would make electricity. But you’d use more energy to move the turbine through space than you’d get back.

        • Sarcasm

  • A fully charged powerwall would add ~20 miles of range to a Tesla, probably less as towing a trailer is a big drag on efficiency. Perversely on a long distance trip its possible the efficiency drag may actually cost more miles then the charge in the powerwall would add back making your range lower with a towed charge trailer than without it. Assuming it did add the full 20 miles with no efficiency loss do you really think the cost and hassle of a powerwall on wheels is worth it for a 20 mile gain? Particularly considering 20 miles of charge is an extra 5 minutes at a supercharger? It seems a lot of hassle for little or possibly no gain.

  • I think that a range extender trailer that doubled as a home energy storage system is a clever idea that could end the range anxiety sufferings when used on long trips, or when you forgot to plug-in the night before. A trailer equipped with at least 20 KW of batteries could extend the EV car’s range at least 60 or 70 miles. I loved the idea, thanks for the tip.

    • California maximum speed limit is 55 mph for any vehicle with a trailer, no matter how small the trailer is, even if the speed limit is over 70 mph.

• Sending a text or similar is a really important safety feature that I’m amazed hasn’t been added. Although Chris_in_Raleigh says it has so I’m not sure what to think… It’s definitely not a feature of the Tesla app and they’re usually ahead of the curve.

  • I was thinking about this and cars don’t even need to use any complicated internet communication systems to warn of leaving them unplugged. The car can just beep at you for a few minutes if you lock it with under 30 miles of range and it’s unplugged. Press lock again to cancel the warning.

    • Alternately, having a charger that is smart would do the trick. That might make more sense as having a smart charger would allow for better Vehicle to Grid dynamics.

• My Leaf is set up to both text and email me if I don’t plug in when at home; that has reminded me a couple of times when I didn’t plug in as soon as I got home. Also, with a 240-volt charger, you can add a surprising amount of charge to the battery in just a few minutes; it starts fast and slows down as the battery gets closer to full charge.

  • Not all Leafs have Carwings. That’s what enables the communication. I think it should be a feature on all EVs because of their nature…period.

• I’d like to add making the quick chargers not require a membership. I have a Leaf as well and encountered a similar scenario yesterday. I went to the nearest quick charger thinking I could swipe a credit card and “fill up”, but it required a membership and I didn’t have time to go through it. The quick chargers should be like Blink chargers where you pay more for not being a member but is more in line with filling up at a gas pump as far as ease of use and payment.

  • I have the NRG eVgo card that I don’t pay a monthly fee for but as you noted, I do pay more per charge. I only plan to use it once or twice per month so it’s not a big deal.

    • The bummer is that I wasn’t able to get a membership at the charging station so it still requires forethought. EV adoption still hinders on making it as easy as gas cars.

  • I agree. Here’s a radical concept. Accept credit card payments.

    Membership cards are all well and good, and can offer discounted fees etc, but don’t refuse to charge if the owner isn’t a member or prefers not to be a member of your special little club.

    I can buy groceries at Kroger regardless if I have their loyalty card or not. I may pay more by not having a loyalty card. EV charging should be the same.

• i had a gasoline car once of which the gas meter was broken.

  we too lived on a hill so i could drive with shut down engine just to the nearest gas station

  • True, that worked…but in an EV, I actually gain range and glide down the hill 🙂

• Many don’t actually realize but in a leaf, you can increase range quite a bit by using Neutral down hills and B mode for slowing down. In snow your habits all become pre-emptive and safer. I’ve had many close calls but never once hit %0.

  • When do we get EVs that tell the driver it’s time to charge and guide them to an available (and working) public charger?

    Your car should be able to give you notices based on your comfort level.

    • Tesla does that. When it decides you’re at risk of driving out of range of that nearest charger, it warns you and offers to plot a route to an in-range charger of your choice. It doesn’t just use distance from charger but also takes into account elevation changes, temperature (lower temp means lower range) and even headwinds, supposedly.

      • And that’s how things should work…

        • The Nissan LEAF works in a similar manner also.

          The Nav system alerts you if your destination is beyond the cars range at any point in the journey and provides charging locations along the way. The LEAF Nav system isn’t the easiest to use, but if you search Youtube you’ll see examples of folks planning long routes in their LEAF (with mixed results).

  • B mode is great! I use it all the time during traffic and coming up to stop lights.

  • I find on a long down hill you are better off setting the cruise control and set the regen to max, it adds energy to the battery as you descend and prevents you from exceeding the speed limit.

    I use neutral in situations where there are rolling hills, you can build up speed when going downhill (free acceleration) and use the extra speed going up the next hill. Rinse and repeat. This minimises the amount of time you spend using the motor to ascend hills.

• Funny you should post this article. I asked the same question a few days ago and was cursed as an idiot for being so stupid.
  “it should never happen” was the consensus – EV drivers and cars are smarter

  • Should be.

    Could be.

    • Would’ve, could’ve, should’ve 🙂

  • I guess it was my turn to be ‘that guy’… :/

• Car needs to connect with “Google Now”. Then it can look at your schedule, know how far you’ll be traveling tomorrow, and calculate the minimum soc you’ll need.

  I expect Tesla will have this soon. It’s already connecting to calendar.

  • That’s what I’m talking about. Google now is great. Can’t wait until my car is that smart.

• This is where one of those wireless chargers you park over would pay for itself, right?

  • It would have helped for sure. Just wish they were more efficient.

  • I want a laser that fires into a charger on the roof!

• I’ve never been stranded but came close once when I was still getting used to the Leaf. Once a week I have a 74 mile round trip with no access to a quick charger. It’s usually no problem if I stick to the back roads for half of it. However, one day with extreme winds put me at low battery when I was still 20+ miles from home. I drove until the GOM blanked out, soon followed by the charge meter blanking out, and finally just a couple miles further before I chickened out and asked a Panera Bread if I could charge off an external outlet. The staff agreed and had a great time checking out my Leaf. Meanwhile, I ordered some dinner there and waited. After an hour I figured I could make it the rest of the way (about 4 miles), and I did, but the GOM and charge meter were still blank. It goes to show how painfully slow level 1 charging really is!

• I’ve forgotten to plug my car in once. I had to make the call in and say I’d be late because I’d forgotten. It was embarrassing.

  • Your transparency is commendable. You could have saved yourself some embarrassment by saying the car wouldn’t start and you’d be in later.

    I’ve yet to forget (came close a few times and my car reminded me via email). I’m fortunate enough that there are 4 DCFC units on my way to work, 2 within 10 miles of home. My worst case scenario is I will be 30 minutes late.

    • Well, I was only 30 minutes late as well. I plugged the car in, and in 30 minutes, even my crappy slow on board charger gave me 10% charge, and I only need 20% to get to work, and she wasn’t bone dry from the previous day. So, I missed my first meeting of the day, but wasn’t super late by any means.

• Just for fun I drove our Leaf to the top of Pikes Peak 14,110 feet elevation. At the entrance to the PIkes Peak Hwy I checked the battery % level and at the top and then again at the exit to the Hwy. We recovered 49% of the battery level used to climb the peak.

  • That’s very neat. I’m curious what that would look like in the different seasons – Summer at 90 degrees, winter at 20 degrees etc. I know temperature affects range but not sure how that conversely might affect regen though I suspect there would be a similar impact. Not sure…

    • I picked a day with comfortable weather during National Drive Electric Week. Later that week we brought the Leaf to an event to share. In total, it was greater than 8000 foot gain in elevation plus some distance to travel to get to the base of the mountain. Due to reduced battery capacity and heater use in cold weather, I don’t think we would make it to the summit in winter.

      • Crazy but not terribly surprising. My brother lives in Colorado Springs and I was out there a few months ago. Took the cog up to the summit and couldn’t imagine starting the run up that with a Leaf. The upside is, as you mentioned, that you’ll recoup lots of the expended energy on the way back down…in addition to traveling the same miles downhill. Thanks for sharing!

  • This experiment demonstrates the value of reducing energy use over producing clean energy. 1 kwh saved is worth 2 kwh produced in this example. So for driving efficiently, you’ll do better to reduce your acceleration and overall speed than using regen aggressively. When you have the option, you’re better off going around the hill than over it if that means traveling less than 49% greater distance.

• Why the regenerator used to regenerate the power back to the battery is not connected to the electric motor by V-belt to regenerate power all the time and not only in breaking?

  • Because of the 2nd law of thermodynamics.

    If you take 1 kW out for regenerative braking, you’d have to put more than 1 kW in to make up for the losses that were incurred in doing so.

    There is no free lunch.

    • When we rotate the generator shaft to generate electric power, the shaft is in a steady state and only friction will consume power but with good librification this should be very minimal it should be the same power lost to rotate the motor shaft itself.

      • Go read up on the second law of thermodynamics to learn why this is a bad idea.

    • I could have read one more comment down and found a better answer.

  • You’re drifting into perpetual motion land.

    You can’t attach a motor to a generator and get as much out of the generator as was used to drive the motor. There are friction losses all along the line.

    • Ok, how about attach the re-generator to a fan rotating by the wind created when the vehicle speed up ?

      • Is that a serious question?

        • yes

        • OK, it’s the same problem as your V-belt idea. It takes energy to push the car forward and that forward motion uses energy. Stick a wind turbine up in the wind and it takes more energy to drive the car forward.

          Start with the efficiency of electric motors. They turn about 90% of the electricity going into them into kinetic energy (motion).

          If you could feed that kinetic energy back into the batteries with no additional losses you’d still put back only 90% of what you took out.

          The generator run by V-belt or wind turbine blades is also less than 100% efficient. More energy lost.

          You might use a kWh to drive the belt or blade powered generator but get only 0.6 kWh.

        • Thanks

• Nice article on a practical topic. Thanks, Kyle.

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