Exclusive Interview with Chevy Bolt EV Chief Engineer

The 2017 Chevrolet Bolt EV will be available for sale in less than a year. A five seat hatchback with a 200+ mile electric range with a base MSRP of about $37,000. Will the Bolt affect i3 sales?

This week at the North American International Auto Show I had the opportunity to sit down with Chevrolet Bolt EV Chief Engineer Josh Tavel. We covered a variety of topics related to the Bolt EV, which was the cornerstone of the Chevrolet press conference at NAIAS this year. I originally posted this on InsideEVs, but I believe the readers here would also be interested in reading about a potential i3 competitor which is coming to market in less than a year. 

I started out asking Tavel what he felt were some of the biggest challenges his team faced with the Bolt.

Here’s Tavel’s response:

“This is a very different car.” 

“You might expect me to answer this by saying one of the major components like the battery or electric motor, but that really wasn’t the case. We’ve been doing batteries and electric motors for a long time at Chevrolet so they’re known entity for us.”

“The biggest challenges were really because the vehicle architecture of the Bolt is different. It’s the unique packaging of the Bolt which was probably the biggest challenge. It affects everything. Some of the predictive models, the CAE (computer aided engineering) work really well with conventionally powered vehicles, but when you take yourself out of that architecture and apply it to this new type of vehicle, they don’t work that well, so we really had think differently. There were a couple of areas where we had to take a different approach, because this architecture is so different than anything we’ve ever done.”

Talking about crash testing, Tavel stated:

“In crash testing, cars have unique crash test signatures, but the results of the Bolt are unlike any other car. That said we’re feeling really good about us being at the top of the segment from a safety perspective.”

He went on to talk about how they spent time slimming down the front seats in order to give the rear passengers more leg room and save weight, but how that then affects crash testing, and how the battery tray is incorporated into the main structure to increase the stiffness of the chassis.

Regenerative Braking

The Bolt has two driving modes, drive and Low. The regen level in normal mode is minimal, and basically simulates how a conventional car without regenerative braking feels. I specifically asked him to describe how “Drive” mode feels. Tavel explained:

“It’s still in the same field as a normal car. There are normal cars that have as much natural decel as the Bolt in Drive; it’s not out of the norm. Originally it was tuned such that if you were to take 100 people and monitor them coming to a stop light, and monitor that decel, and let’s say it would be about .2g’s. The Bolt was designed for .2g’s – to basically act like a conventional car. But the problem was, sometimes you need a little bit more, and it didn’t give it.”                                                                                                                                                                                                                                                                                                           "So actually just this past December we were all out in LA and I said ‘You know guys, this is stupid. It feels like were making the one pedal driving be kinda acceptable for the people that don’t like it, and kinda acceptable for the people that do. Why are we doing this halfway? If they don’t like it, they have drive (mode), the i3 for instance, doesn’t have a drive mode with light decel. So if they don’t like regen, go to drive. If they want it, give it to them (low mode with heavy regen).’ So now we’re at a spot where I can drive home and never touch the brake pedal.”

In addition to the Low drive setting, the Bolt has a Regen on Demand paddle on the steering wheel. So there are actually four different levels of regen with the level of deceleration getting stronger at each level below:

• Drive mode (mildest regen <.2g’s)
• Drive mode using Regen on Demand paddle
• Low mode
• Low mode plus using Regen on Demand paddle (strongest regen ~.3g’s)

Artificial Creep

In order to come to a complete stop while in Drive mode, the driver will need to use the friction brakes. In these conditions, when they release the friction brakes, the car will creep forward. Artificial creep and whether or not it belongs on an EV has been a highly controversial topic and one debated amongst the plug in community. The Bolt has a unique way of dealing with it. If you don’t like strong regen and use drive mode, the engineers feel you probably like how a conventionally powered car performs and they give you artificial creep.

However, if you like strong regen and use low mode, or stop with using the Regan on Demand paddle, the artificial creep is disengaged. In those circumstances, the car will hold its position there, even if on an incline. There is no need to depress the friction brake. However, if the operator does press the friction brakes after coming to a stop using the regen, and then releases the brake pedal, the car will creep forward.

The Bolt uses the same DC fast charging standard as the i3, the Combo (CCS) system.

DC Fast Charge

With Tesla currently charging at over 100kW, and Audi & BMW talking about the new 150kW system they are working on, I asked Tavel what would be the highest speed of DC Fast charging the Bolt would accept. It’s clear this topic is one that is still being internally discussed, but I also got the feeling it will most likely be limited to what the current hardware in the ground can deliver, that being 50kW.

“We’re still figuring out how fast we want to go. We’ve over validated a lot of our components just in case, but were still figuring out if we want to limit it to say, 50kW’s or 60kW’s or possibly higher. That decision hasn’t been made yet but I can promise it won’t be lower than 50kW.”

Torque Steer

I drove a MINI-E for two and a half years so I know have a front wheel drive EV with lots of torque can feel. The MINI-E was a blast to drive, but under full acceleration I needed to hold the steering wheel tightly with both hands to keep it from jerking from side to side from the torque steer. I wanted to know how the Bolt would feel with 200 hp and 266 lb-ft of torque going to the front wheels.

“We’ve got some special controls in there for that. Our steering system and our EBCM (electronic brake control module) has some pretty slick calibrations in there to combat torque steer. You can feel a little bit of it but I think it feels fine. There’s a lot of power up there so if you were to remove the controls we put in place the torque steer would be pretty wicked.”

Comparing the Bolt to the Volt

I asked Tavel to describe the performance of the Bolt, and possibly compare it to the plug in competition. Unsurprisingly, he chose the Volt as the car he would most closely compare the performance to.

“The Gen 2 Volt I think is a great car. Amazingly, I’d like to say that I believe we’ve worked it out so that performance wise we’re equal to where the Volt is. To me, there is no competitor I wanted the Bolt to be like. I think the Volt, the Gen 2 Volt specifically, is a really well done car. And that is a car we compare ourselves to a lot. 

The Bolt has a traditional-looking gear shifter. Other EV's like the i3, the Model S and the Nissan LEAF have ditched the traditional shifter for something different, since gear shifting really isn't necessary on an EV

Why the traditional gear shifter?

Since electric cars don’t really require a gear shifter, and some manufacturers like BMW, Nissan and Tesla have ventured from the norm of the traditional gear shifter on their electric offerings, I asked why the Bolt has what looks like a gear shifter for a traditional automatic transmission. Tavel was quick to dismiss the need to change what works.

“This isn’t some funky looking car that’s some whizzy statement. This is a mainstream car that happens to be propelled by electrification. It’s not some unique quirky little thing. (I couldn’t help but think he was referring to the BMW i3 here) It’s a real, no kidding, good car. It’s already an electric shifter, if you pull that away the car gets maybe a little more different than you might want, and quite honestly I think there are some questionable safety issues if your reaching up and moving things up there that I don’t think as a company we want to go to right now.”

Side note: Right as I was asking this next question, Carlos Ghosn and his entourage were escorted onto the platform behind us to have a private look at the Bolt on display. I couldn’t hear exactly what they were talking about, but he wasn’t smiling.

No Carbon Fiber?

The Bolt’s press release from GM stated the Bolt incorporated advanced materials including aluminum, magnesium and carbon fiber to help lightweight the vehicle. I asked him if he can explain where these materials were used, and how they helped save weight. Tavel was surprised there was a claim that carbon fiber was used on the Bolt, and in fact told me he believed that was incorrect. As for the use of advanced materials and light weighting, he said:

“We saved just shy of 50lbs by using all aluminum enclosures (all the exterior body panels are aluminum). The underbody is 95% high strength steel or advanced high strength steel, some of it is the first time it’s been used in production so far. The upper body, not counting the exterior panels is about 80% high strength steel, so there is a lot of advanced materials in there, but we didn’t use carbon fiber anywhere I can think of.”

On high tech advanced electronics

With more and more advance electronic features becoming available in today’s cars, I asked if the Bolt would feature any of these technologies. I specifically asked if the Bolt would have adaptive cruise control, lane departure assist, self parking, automatic braking or any autonomous driving features and I was a little surprised to hear it won’t, not even as optional equipment. They will however introduce a few new features that weren’t on my list. Tavel explained:

“No. Adaptive cruise control – no, you would need the blended brakes to do that and we didn’t want to do that with this car. However, all the standard side blind zones, rear cross traffic alert, ten air bags, all that’s there. What’s new is the optional Rear Camera Mirror. You normally have a 22 degree field of vision with a standard mirror, this takes you to 80. We also have optional Surround Vision, which you know is the 360 degree camera system. We’re still working hard to perfect it, but I’m told it’s the best one camera systems the guys have seen so far.”

Conclusion

Overall, I really got the feeling Tavel was extremely proud of the Bolt. He took particular pride in talking about how different this car is from anything GM has ever produced, and that his team worked relentlessly on every small detail to try to achieve perfection. While they are still actively improving things, they are actually pretty close to a finished product.

In fact, he said GM has executive test drives every week, and after some of the top brass drove the Bolt last week, they told Tavel he could release the car now, and as far as they are concerned it’s finished. He’s not satisfied yet though, and that’s what you’d expect from your chief engineer.

BMW i3 REx One Year Review

Delivery day: May 21st, 2014

Well that went by fast. After waiting patiently for years for BMW to bring the "Megacity" car, their first production electric vehicle to market, my first year of ownership really flew by quickly. On May 21st of last year I was the first i3 REx delivery in the US. My one year review is about a month late, but that has only given me some more time to gather my thoughts about it.

About a month into ownership last year, I authored two posts dedicated to my initial likes and dislikes. Many of those initial thoughts still hold true, but I've also had some changes of opinion as well as discovering new annoyances and new attributes which I appreciate.

One of the few pictures I have of my car in its real color; Laurel Grey. I wrapped it red the first week I had it.

Overall I'm very happy with my i3 and there isn't another car I'd prefer to have. It really suits my needs while offering the perfect balance of performance, utility, comfort and efficiency that I desire. I managed to pile up a little over 25,000 miles by my first year anniversary (I'm up to about 27k now) with 23,700 miles on battery alone and 1,300 miles with the REx engine running. That equates to about 95% all electric miles. I'm sure some will question whether I needed the range extender option at all since I only used it for about 5% of my driving and that's a valid question. I guess I didn't really need it, but I definitely don't regret spending the additional $3,850 for it and I'll explain why.

The REx performed perfectly on my 462 mile road trip from New Jersey to Vermont. Going there and back I drove a total of 111 miles on battery and 351 on the REx, needing a little under 10 gallons of gas for the trip. I'll gladly replace gassing up on long trips with a couple 30 minute quick charge stops once the infrastructure matures, but for now the REx is my best option for the occasional long trip.

First and foremost, the range extender allowed me to take the car every day without even thinking twice about whether I had enough range or whether or not I would have the opportunity to plug in during the day. Back when I did my initial likes and dislikes, the first thing I pointed out was that I think BMW missed an opportunity to separate themselves a bit from the pack of "80 mile EVs" out there. The 81 mile EPA range rating for the BEV i3 was just a little too low for me so I went for the REx. As it turns out, there weren't too many days which I needed the REx, but having it there allowed me to take the car on days I may not have because I wasn't sure how far I might need to drive that day. So in reality, the range extender allowed me to drive more electric miles than if I didn't have it. I'd say I probably only needed the REx about two or three times a month on average, and even then it was usually for less than twenty miles. There were a couple long road trips which accounted for the majority of miles, and a few times I needed it for 30 to 50 additional miles. When I first got the car I took it to get wrapped and the shop was about 130 miles from my house. The drive back was nearly all on the range extender. I took a couple 150 to 200 mile round trips, my wife took the car on a business trip to Pennsylvania and I also made a 462 mile round trip to Vermont. It's true I could have managed without the REx, but having it there increased the utility of the vehicle immensely and if I had it to do all over, I would definitely get the REx again. However, if BMW had optioned it with a 28-29kWh battery pack (33% larger), I would definitely choose that over the REx.

The car is holding up well and there are no squeaks or rattles to report. My interior still looks brand new, even with heavy use and high mileage for one year. I'm pointing that out because I have heard a few i3 owners report their leather seats showed premature wear, and even a couple people say the eucalyptus wood dash panels developing cracks (which BMW replaced under warranty). I have nothing negative or unusual to report on this though. Since I wrapped the car shortly after getting it, I can't really comment on how the exterior painted surfaces are fairing. Since this is the first BMW with all plastic body panels, and since BMW developed an entirely new way of painting the panels which uses 70 percent less water and 50 percent less energy than painting systems employed for their steel body panels, I think it's fair to wonder how well the painted panels will hold up over time. I have had a few people ask me how the wrap is doing and I can say that after a year of driving in New Jersey (including a harsh winter with a lot of snow and ice) the wrap is beginning to show signs of wear and even peeling on some of the corners. You really have to be looking at it hard to find the problem spots, but small issues are surfacing which I'm sure will only get worse. I really only intended to keep it wrapped for a year or so, so I'm not concerned. I figured this would happen after about a year. Just keep this in mind if you are planning to do a vehicle wrap. 

The wrap is bubbling a bit on the side mirrors

Wheel well beginning to peel

The redesigned fuel sensor

Over the year I had a couple of maintenance issues which needed service. The good thing was my dealer, JMK BMW, has i3s in their loaner fleet so I was able to drive an i3 even when my car was in for service, which amounted to a total of 14 days. The first issue was one that all the early i3's had, a blown onboard charger, or as BMW calls it, a KLE (Komfortladeelektronik or Comfort Charging Electronics in English). One good thing about the way BMW engineered the onboard charging is that there are two 3.7kW on board chargers, one in the main EME (Electrical Machine Electronics) and the other, the KLE, is installed separately from the EME. So if you do have a KLE failure, you can still charge the car, albeit at half speed. I can't give BMW a pass on this issue though. They had five years of field testing with the MINI-E and ActiveE, and to come out of the gate with a faulty on board charger is inexcusable in my opinion. To their credit, they quickly resolved the issue by re-engineering the KLE, and installing it in the existing i3 fleet. I've had the new KLE  in my car for 10 months now, and it's been working fine. There was another issue that all i3's with the range extender had, which was a faulty fuel pressure sensor. Almost immediately after the i3 launched, REx owners were getting a Check Engine light, even if they never fired up the REx. It turned out a fuel pressure sensor was getting corroded by the gasoline used in the US. Evidently the mixture is different from the gas used in Europe where the i3 had launched 6 months earlier without this issue, and the additives in the US gas were creating havoc with the sensor. Again BMW quickly made a new fuel pressure sensor, this one actually has gold plated connectors to resist corrosion.

My battery pack dropped from the car. The heating element is inside, below the battery modules

I also had a flaky voltage regulator for the battery heating element which was occasionally sending an error message. I don't think BMW was sure if the sensor was bad or if the regulator was bad so they just replaced both. That required removing my entire pack to replace the regulator. I was surprised that this major service was accomplished by my dealer in less than two days. The only other issues I had were flat tires; four of them to be exact. It's difficult for me to really assess blame on this, since flat tires are usually the fault of the driver for running over debris or adverse road conditions, but four flats in one year is a little troublesome. Could it be related to the rubber compound Bridgestone used to make these unique tires, or related to how tall and thin they are? The two main problems I have with this are the fact that since the i3 doesn't have a spare, you are left stranded unless the mobility kit (an air compressor and tire sealant) can temporarily seal the hole and allow you to drive home or to a repair shop. Secondly, the tall thin tires are unique to the i3, so they aren't always in stock at the dealer. One time I had to wait four days for the dealer to get one. 

With no spare tire onboard, a flat means you're getting towed

At least with a sidewall bubble you can drive to the dealer, but you still need to buy a new tire and hope it's in stock

Three of the four flats I had were caused by sidewall bubbles, which happen when the inner liner of the tire is damaged. Sidewall bubbles typically happen when you hit a pothole, curb or road debris. In all three cases when I had this happen, I hit a good sized pothole and immediately figured I'd have a problem. Pulling over once it was safe confirmed what I had expected. The other flat I had was caused by a large metal screw. In that case I was actually only a couple blocks from a BMW dealer who actually had the tire in stock and I was able to wait there and drive off about an hour later. A few years back I had a Porsche Boxster with low profile Pirelli tires and had sidewall bubble issues with that car also, so I know this is something that is common with low profile tires. The difference was the car had a spare tire and the Pirellis were available everywhere. If I could go back in time I probably wouldn't have gotten the $1,300 optional 20" sport wheels and I certainly would have paid the $1,000 for the tire and wheel insurance. I definitely like the look of the 20" wheels, but they are lower profile than the 19" stock wheels, and that makes them more susceptible to bubbling. 

91 miles on a charge is my personal best to date

As for the range, in warm weather (over 65 degrees) I can usually beat the EPA rated range of 72 miles per charge. In fact, I average about 78 miles per charge in these favorable conditions. The cold weather takes its toll and the worst range I ever got was 48 miles on a full charge before the REx turned on. This happened back in January when the temperature was below zero with ice covered roads and I didn't precondition the cabin or battery. I actually wanted to see just how bad the range could be in those conditions. However most of the winter when temperatures were under 30 degrees I averaged about 58 to 60 miles per charge. The furthest I ever drove before the REx kicked in was 91 miles, which I did shortly after taking delivery.

I'll now list the top ten things I either find annoying, would like to see corrected or added features to future i3s.

1) Configurable regenerative braking. I'd like to select how aggressive or weak the regenerative braking is. Other manufacturers offer this and the owners I've spoken with appreciate having control over their regen. The i3's regen does increase in strength when in Eco Pro and Eco Pro+ modes, but I'd prefer the ability to manually adjust it.

2) The car needs an extension flaps on the sun visors. There is a huge gap between the visors and early morning drives can be difficult when heading East. 

3) The charging connector needs to unlock from the vehicle when the charging session ends. BMW had said this would be part of the March 2015 software update (which I have) but it still doesn't work. 

The large gap between the visors allows the blinding sun to get through. Visor extension flaps would be appreciated.

4) The front storage compartment (frunk) should be waterproof. If that is problematic then install a snap-on or hinged cover to keep dirt and water spray out. 

The current configuration allows leaves, water and dirt to get into the frunk storage compartment. Anything stored up there gets dirty and wet. A cover would solve the issue. 

5) Remove the annoying disclaimers and seat belt gong every time you turn the car on.  The seat belt warning should give you ten or twenty seconds to buckle up before it sounds the alarm. I might code my car just to remove these.

6) Fix the windshield wiper. It currently pulls water back into the drivers view when it changes direction. During heavy rains there is a significant obstruction to the drivers view of the left side of the windshield. 

The wiper leaves a line of water on the windshield, and actually pulls it back into the drivers line of vision when it changes direction.

7) Add a battery temperature readout. BMW can bury it in iDrive if they don't want it on the main display screen, but put it somewhere. Many experienced electric vehicle drivers want to see their battery temperature.

8) Add a heated steering wheel. In my opinion heated seats and steering wheel should be standard on all EVs, especially ones from premium brands. I would have really appreciated it last winter.

9) Include an AM radio. Other EV manufacturers have figured out how to reduce the interference and offer it in their vehicles. I'm sure BMW can figure this out too, even if the reception isn't perfect. 

When the ACC disengages, you get this warning. The problem is by then it's already disengaged and the car is applying the regenerative braking.

10) Fix the Adaptive Cruise Control and Parking Assistant. These are really great features, and this kind of technology is expected in a car like the i3. The problem is the ACC disengages suddenly and doesn't recognize certain vehicles because of their tail light configuration. The car will drive right into the rear of a Dodge Charger for instance, because the Charger's taillights (which extend across the entire rear of the vehicle) for some reason confuse the ACC. Direct sunlight and sometimes overpasses also cause the system to shut off without warning. I dedicated a post to this issue a few months ago. The Parking Assistant is an automated parking feature which does an incredible job of parking the i3 in very tiny parking spots. It only needs an opening which is 22 inches longer than the car to park it. The problem is, I've had numerous people report to me that the car rubbed the curb during the automated parking, scratching the rims. I've had enough people tell me this happened to believe it wasn't just a couple cars malfunctioning. I believe there is an inherent flaw in this feature which needs to be fixed, so for now I recommend not using the Parking Assistant until we get word that the issue had been corrected. 

OK, so by now you must be thinking I must really hate the i3, considering all these things I've pointed out that I don't like. That wouldn't be correct. I actually love the car and wouldn't trade it for anything, but nothing's perfect, and BMW can definitely make adjustments which would improve the i3 in my opinion. Now I'll dive into my top ten i3 likes. 

1) Spacious interior. For a car that is only 13 feel long, it has a lot of interior room. It actually has nearly the same interior volume as a 3-Series which is more than two feet longer than the i3.

Spacious, comfortable and well laid out. The i3's interior is definitely one of its strong points

2) Beautiful interior. In my opinion the i3's interior is stunning and laid out perfectly. The seats are very comfortable and the outward vision is excellent.

3) It's incredibly fun to drive. The instant torque, combined with the light weight make the i3 the most fun to drive electric vehicle this side of a Tesla P85D. The low end acceleration (under 60mph) is fantastic and it's actually the fastest one of the fastest BMWs from 0-30mph. Somehow the tall, thin tires do their job and keep the car under control in hard turns. While it doesn't corner like an M3, it really does just fine when it needs to. I've let dozens of friends and family members drive it and they all walk away with an ear to ear grin. It's really a blast to drive.

4) Futuristic, sustainable construction. I love the fact that I'm driving the only volume production to ever be constructed with a passenger compartment primarily made of carbon fiber reinforced plastic, an all aluminum frame and thermoplastic body panels. There is absolutely nothing else like it on the road today. Plus, every stage of manufacturing and assembly was developed with sustainability in mind.100% of the electricity used in the Leipzig assembly plant is derived from the wind farm BMW installed on the site. It actually generates so much excess electricity that BMW sells the excess to the Volkswagen AG. Even the carbon fiber plant in Moses Lake, Washington where the CF is made is powered 100% by renewable hydro-power. 

BMW's Leipzig plant where the i3 is made. The on site wind turbines produce more energy than the plant uses.

5) The charging rate. I can consistently pull 7.2kW at home (30 amps @ 240v) and now that there are finally some CCS DC fast Chargers being installed I can look forward to fast charging on the go. I'll soon be installing a 24kW CCS DC Fast charger at my restaurant so I'll have access to it every day. One of the advantages of having a relatively small battery is it charges quickly! I can fully recharge in a little under four hours while charging level 2, and I can be at 90% in about three hours. Tesla is the only EV manufacturer in the US making on board charging equipment which can deliver more than 7.2kW from a level 2 (240v) source.

6) The efficiency. According to the EPA, the i3 is currently the most efficient car sold in America. Over the entire year I averaged 3.9 miles per kWh. In the warmer weather I'm usually around 4.5 mi/kWh and in the winter I was averaging about 3.5 mi/kWh. I should note that I don't drive the car softly, and I'm certain many other i3 owners see much better consumption figures. It's way too much fun to drive it like it was a Prius. Averaging 4 mi/kWh the i3 would cost the average American about $400 per year to drive 15,000 electric miles.

I needed to drive over 200 miles on the range extender when I drove it to Vermont last winter. I set the cruise control to 70 mph and the REx was able to sustain the charge level the entire trip without any issue, even with needing to make a few elevation climbs.

7) The range extender. I know above I said I'd prefer a larger battery over the REx, but that just isn't an option at this time. As far as range extenders go, I like how BMW set this one up. It's truly an auxiliary power unit, one that has no physical connection with the wheels and cannot drive the wheels under any condition. It's sole purpose is to maintain the battery state of charge and allow the driver to continue along until they have the opportunity to plug in. You'd never buy an i3 REx and not charge it, simply driving on gas all the time. It's not meant to drive just as well on gas as it is on electric and I like that. It's an electric car with a secondary power source meant for occasional use, and in that vein it works perfectly - well for me at least. In all of my REx-ing, I never had the vehicle go into reduced power mode which can happen if you are using more energy than the 650cc engine can deliver. This can happen under long sustained hill climbing at highway speeds. BMW is currently working on a solution which will allow for more robust range extender use. This feature will be called Hill Climb Assist and will be available in the Fall. All current REx cars will get the update. There is another option which some owners have done, and that's coding the car to allow REx-on-demand. I have not done that to my car because the range extender has been able to do anything I've called for it to do so far, and I've found that as long as I set the cruise control for 70 mph or lower, I can drive indefinitely, provided I keep refueling every 60 miles or so. Probably the best thing I can say about the range  extender is it's allowed me to never even think about my range anymore, I just get in the car everyday and drive. 

Resting at home. You can see the winter tire/wheel combo on the rack above the car. The Bridgestone Blizzak tires were excellent in the snow. I suspect this was an instance where the tall, thin tires actually improved the traction.

8) The attention. Everywhere I go people stop and ask me about the car. I understand many people might not like that, but I do like talking about it and having a discussion about why they should consider driving electric too. I know there are people who think the i3 is ugly, but the response I get from the majority of people is they think it's cool. I don't think the i3 is the best looking car on the road, but I definitely don't see it as ugly and neither do most of the people who stop me to ask about it. When I'm working I can see it through the windows in the parking lot. Every day people walk up to it, look inside and many take pictures of it. Like it or not, it generates a lot of interest.

9) Battery management system & preconditioning. The i3 has a sophisticated thermal management system which works with the preconditioning feature to keep the batteries within the optimum operating temperatures. Which, for the Samsung cells used by BMW is 67 to 104 degrees Fahrenheit. When the batteries are much cooler than 67 degrees, you begin to lose range and when the battery temperature is above 104 degrees the cells degrade and begin to lose capacity. Excessive heat can be one of the biggest enemies for prolonging lithium ion battery life so a good thermal management system will help extend the battery's life. The i3 uses R134a refrigerant which not only works very well, but also is extremely safe in the event of an accident. Liquid based thermal management systems have an elevated risk of fire in the event of a battery module rupture. In many of these systems it's possible for the liquid to act as an accelerant, and intensify the fire. R134a is an inert gas and simply dissipates in the event of a ruptured pack or fire. It's actually the same refrigerant used in most car air conditioning systems. I'm not saying I think liquid thermal management systems aren't safe, because that's not the case. I just believe using an inert gas is better, and the i3 is the only EV to employ this technology so it's worth noting. It's just another aspect of the car which demonstrates how far outside the box BMW went when engineering the i3, and a perfect example of why the i3 has been called "The most advanced vehicle on the planet".

The i3's navigation "spider map" offers a pretty accurate visual display on the cars current range in the different driving modes.

10) A lot of small things add up to really enhance the ownership experience. Besides the usual attributes expected in all electric vehicles like the quiet cabin and the smooth linear acceleration with instant torque, the i3 has some extras that really seem to make the whole car exceed the sum of its parts. I love the hill hold feature which keeps it from rolling like many other EVs do while stopped. The absence of artificial creep is a welcomed "addition" that some other EV manufacturers just don't seem to get. I've done more than one poll on this topic and the vast majority of people say they don't want artificial creep in their electric vehicle and BMW got this right. I love how the aggressive regen really allows "one pedal driving". While I did mention above that I wish the regen was adjustable, the level it's set at now is just about perfect for me in most driving conditions. Adjustable would be better, but as is the regen level is very good, probably the best of any electric vehicle in my opinion. The soft speed limiter helps to coach you to drive more efficiently if you want to, and the three different driving modes (Comfort, Eco Pro & Eco Pro+) gives the driver the ability to extend their range significantly. The "spider map" display in the navigation system shows how far the car can go in each driving mode, and alerts the driver if their selected destination is beyond the range, pointing them to possible charging stations along the desired route. The brake assist will sound an audible alert if it senses the car is rapidly approaching the vehicle in front of it and it will even apply the brakes automatically if you are going under 30 mph and it determines you are about to have a possible collision. I also really appreciate that most BMW dealerships now have i3s as loaner cars so i3 owners can continue to drive electric even if their car is in for service. Finally, the large center display screen is as crisp and clear as any I've seen. It is positioned so there is almost no glare issues and the HD rear view camera is television-quality clear.

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The "Secret Service Menu" shows I have 19.1 kWh available when fully charged

So that pretty much sums up my thoughts after one year of ownership. I listed ten positives and ten negatives and hope the information above helps to paint a picture of what I believe are the i3's strengths and weaknesses. One more topic I'd like to touch on though is battery degradation. There are a lot of people curious about how well the battery is holding up over time and use. I'm going to be doing a more comprehensive post on this soon, but I'd like to at least mention what I've observed after 13 months and 27,000 miles. Fortunately, the i3 has a "secret service menu" in the OBC which allows the battery capacity to be displayed. While BMW officially states the i3 has a usable 18.8 kWh of the 21.6 kWh total battery pack, the service menu indicates we get a little more to access. An entire kWh more in fact. When new, the service menu shows approximately 19.8 kWh available. I've had others report seeing slightly less, but the majority of people who know how to access this info have told me the highest capacity figure they've seen was 19.8 kWh. I have been checking my capacity and watching it slowly decrease. It's currently showing that I have 19.1 kWh available, which would mean I've lost about 3.5% of my capacity in 13 months and 27,000 miles. I've plugged about 700 times during the year and virtually always charge to 100%. I'll be keeping an eye on this and will report back on the capacity loss here from time to time.

I have an 8.8kW solar array on my home in Chester, NJ. It generates most of the electricity I use for the house and charging needs.

I'd like to also point out that during the year, BMW added a numeric state of charge display. This was something I, and many other i3 owners asked for. It might seem like a minor detail, but what's most encouraging is BMW responded to their customer requests and through a software update added the SOC display. Of course there was always a SOC display there, in the form of a bar graph, but many people wanted to see it displayed more precisely, in a numeric value as well and BMW delivered. Now let's see if we can get the battery temperature display in year two...

By toggling through the OBC options, you can see the SOC of 47% in the upper left hand corner of the drivers display screen.

In closing, the i3 pretty much ended up as I expected. It's far from perfect, but so is every other car I've ever driven. I wish it had a larger battery (or a larger battery option), a few monochromatic paint scheme options (like I did with the wrap), offered in a "sport" version with the coilovers that come standard in the Japanese market and a few other sporty upgrades and I think BMW needs to address the issues with the ACC and Parking Assistant features. I don't mind that the moonroof isn't available in the US, and the unconventional exterior styling doesn't bother me. I am much more concerned with the car's interior since that is what I interact with while driving. Speaking of driving, for me it really all comes down to that. The i3 delivers more fun than you should legally be allowed to have at 4 miles per kilowatt-hour.

462 Mile REx Road Trip: New Jersey to Vermont

Perhaps the most discussed topic of the BMW i3 is the implementation of the range extender for the North American market. In an effort to have the vehicle qualify for the California Air Resource Board BMW set restrictions on how and when the range extender can turn on, effectively reducing the utility of the REx. These restrictions are most apparent when attempting to use the car for long journeys which include drastic increases in elevation.

This topic has been covered here and on every other EV site extensively, and recently it was announced that BMW is working on a software update that will allow, under certain conditions,  the range extender to come on much earlier than the 6.5% threshold it currently uses. I am actually beta testing that software for BMW now, having had it installed on my i3 just last week. The new software also includes some other updates that will be standard on 2015 i3s and will be uploaded to current i3 owners sometime early next year.

However this post will detail a New Jersey to Vermont road trip that I took a few weeks ago, just before I had the new software update. My in-laws live in Vermont, and I had been wanting to take this trip with the i3 ever since I got it, but I just haven't had the time. Once I knew I would be getting the new i3 software which would be adjusting how the range extender would work, I knew I needed to make the journey before I had it done, so I could perhaps compare the difference in performance the next time I go.

The Active Cruise Control is awesome. I don't think I'll buy another car that doesn't have it. 

I have taken the car on a few 200+ mile round trips, having the ability to charge up before heading home, but this would be much further, about 250 miles there and about 210 miles back home. The trip there would be longer because we were meeting at a restaurant farther into Vermont before heading back to the house. A couple of years ago I installed a Clipper Creek CS-40 at my in-laws' house, knowing that the day would eventually come when I drove an EV there, but I had never used it until now. My previous EVs (MINI-E and ActiveE) would have just been too much of a hassle to try to make this long of a trip, but the range extender is perfect for an occasional trip like this - or at least I hoped it would be.

Most of the roads in Vermont were covered in ice and snow. My new Blizzak snow tires performed very well and I definitely recommend them for i3 owners who need to drive in the snow.

The truth is, I really didn't know if such a long trip at highway speeds, which would include an overall elevation gain of nearly 1,000 feet would be doable without the car going into the dreaded reduced-power mode, where the vehicle slows down for a while so the REx can replenish the battery a bit. Also, in the final 50 miles of the journey I needed to climb 500 feet before descending 500 feet and then climb about 700 feet to our destination.

My wife and I set out early on a brisk morning with the temperature being only 15 degrees when we left. I didn't precondition the battery or cabin, and the total weight we were carrying was about 450 lbs between me, my wife and the items we were bringing up to her parents'. I topped off the gas tank the night before and left fully charged. The trip is nearly all highway and my plan was to set the cruise control for varying speeds between 70 mph and 75 mph to see how fast we could go with the REx maintaining the state of charge. I would drive the whole way there in Comfort mode and possibly use Eco Pro for the return trip.

A few blocks from our destination we came across some cows.

The combination of the very low temperatures, using the heated seats, cabin heat and  driving 75 mph meant the range extender turned on after only 48 miles. That's the earliest I had ever seen it turn on before. I had barely made it to the New York State border and I was already running on gas. So now I had a little over 200 miles to go and it would be all done on the range extender. I figured I'd need to stop three times so we searched the GPS for gas stations that were directly along the route and at the intervals we needed. I wanted to stop when we had about 10 miles of range left and we were able to pretty much get close to that on all three stops.

I needed to stop three times to fill up on the way there.

We made the first stop right about at the 100 mile mark which was about two hours into the journey. My wife laughed at how quickly the tiny gas tank filled up and we came up with the idea that she would time me on future stops to see how long it took to fill up. She would use the stopwatch app on her phone and we would start it when we exited the highway and stop it when we were back on the highway to see just how long the diversion was. We averaged a little over 2 minutes per stop and the best time was one minute, forty eight seconds. All three stops added a total of about seven minutes to the trip - not exactly much of an inconvenience.

The car looked like I was off-roading all day when we arrived. I finally got to test out the EVSE I installed at my in-laws' house over two years ago. Thankfully it worked.

For most of the trip I had the Active Cruise Control set to 70 mph, but I also spent some time with it set to 73 mph and 75 mph. As I expected, 70 mph seemed to be the sweet spot for holding the SOC. Even with inclines that lasted for a mile or two the car never went into reduced power mode. When I set it to the higher speeds it could maintain the SOC on flat ground, but the inclines had the SOC bar graph getting dangerously close to completely evaporating so I kept it at 70 whenever I was going up any kind of hill. One thing I can say, the Active Cruise Control really rocks for long drives like this. It holds the speed, slows down when the vehicle ahead reduces its speed and maintains a nice safe distance. I used it for virtually the entire trip and it is definitely worth the cost if you do a lot of highway driving.

We arrived after nearly 255 miles. About 207 of those miles was done using the range extender.

So, we made it without ever going into reduced power mode. I guess there is no need to do a comparison trip with the new software since this trip went flawlessly. The only thing I can think of doing is possibly trying the same trip with the ACC set to 75 mph the whole way to see if the new higher REx buffer allows me to maintain the faster speed. As it is now though, 70 mph is definitely the magic number for long distance REx driving. If most of the trip is on relatively flat terrain, the SOC buffer is big enough for sudden bursts of speed for passing and to sustain climbs for a few minutes and a couple of miles. Even though it worked out fine for me, I'm happy that BMW is increasing the battery buffer so longer, sustained mountain climbing will be possible without going into reduced power. I haven't had enough time with the new software to really comment on how well it works yet but I'll do that soon.

The final stats for the trip

The trip home the next day was pretty uneventful. I did precondition this time and drove the first half of the way in Eco Pro mode. It was also about ten degrees warmer. All that combined to allow us to go 15 more miles on battery than we had the day before, giving us a total of 63 miles before the range extender turned on. We arrived home with 462 miles on the trip odometer and an average consumption of 3.4 miles per kWh. I filled up with gas about 1.5 miles from my house so we left and arrived with a full tank. Including the final stop to top off we made seven stops for gas (3 going and 4 returning) and bought a total of 9.87 gallons of gas. We drove 111 miles on battery and 351 miles with the range extender running and averaged 35.5 miles per gallon. That's a little less than what I usually average for the REx, but this was a continuous 70 mph for the vast majority of both legs of the trip so I expected it to be lower than usual. If we had taken our other family car like we usually do for our Vermont trips, we would have needed 19 or 20 gallons of gas or about double what the i3 needed.

Getting ready to leave for the return trip back to NJ

In conclusion, these kinds of journeys are definitely not what the i3 REx was really developed for. The tiny 650cc motorcycle engine isn't really engineered to operate for hundreds of miles at a time and I'm sure if it was subjected to this kind of use every week it would certainly have premature mechanical issues. However using it as I do, for the occasional 10 or 20 miles here and there, or the final 3 miles on some days just to make it home plus a road trip every month or two, it's really a great alternative to spending an additional $20,000 for a battery that's triple the size of the i3's. The range extender model is a good stop-gap measure until there is a decent DC fast charge infrastructure in place, which is really the ultimate goal. BMW has some very good news with regards to DC fast charge infrastructure that they will be announcing very soon, perhaps even at NAIAS in January. They are making a significant investment in this area and I believe the EV faithful will be very happy when the news is announced.