Say It Ain’t So – BMW Omits State of Charge Indicator on US i3


One of the advantages of not being first to market in any industry is the fact that you get the opportunity to study the competition’s product and see what worked and what didn’t so you don’t make the same mistakes. One example in the EV industry would be to look at how Nissan is having difficulty with early battery degradation in the LEAF, especially in hot weather climates.

It seems clear a sophisticated active thermal management system greatly reduces these issues by keeping the cells from overheating and from remaining at very high temperatures for prolonged periods of time. Besides watching the competition, BMW also gained a lot of useful data and feedback from the MINI-E and ActiveE programs. This, in my opinion, should have greatly reduced the chance that BMW would make a major mistake with the i3.

MiniE SOC Was Front and Center

MiniE SOC Was Front and Center

*Editor’s Note: This post originally appeared on Tom’s “The Electric BMW i3” blog.  We urge you to check it out by clicking here.

After driving the i3 four separate times now, I am pretty convinced it provides the driving experience I was hoping for. It’s very quick and instantly responsive, has very precise steering and extremely short braking distances. The regenerative braking is nice and strong, although it’s slightly weaker than it was on the ActiveE. It’s definitely is the “hot hatch” I was hoping it would be.

That being said, it’s not perfect – and I didn’t expect it would be, but I didn’t expect BMW to make an obvious critical error that could have easily been avoided, which I believe they did by omitting the state of charge display.

Both the MINI-E and ActiveE had a numeric SOC display and honestly that is all I ever use when I’m driving. I don’t care what the estimated range indicator says. No matter how precise it is, it doesn’t know how fast I’ll be driving, if I am carrying three passengers with cargo or driving alone, if I’m going to be driving up a mountain or on flat ground. All these factors will influence how far the car will take you on any particular trip.

The state of charge indicator is crucial for me and I believe I’ll feel lost for a while driving an electric car without it. Sure, I’ll get used to the bar graph on the drivers display screen, and I can kind of figure out the approximate state of charge, but that’s unacceptable as far as I”m concerned. Let me see my state of charge and I know how far I can go. I’m not saying BMW should eliminate the other information they what to show, like the bar graph and estimated range. Go ahead and display that on the main drivers screen if you like, but give me the SOC somewhere so I can look at it if I want to. The car has the information available, why not include it on a screen somewhere, I don’t mind if I have to look in the iDrive to find it.

ActiveE SOC

ActiveE SOC

BMW had a special event private at the LA Auto Show for ActiveE drivers only. I believe most people felt as enthusiastic about the i3 driving experience as I did, yet a lot of the conversations were about the lack of a state of charge gauge and how baffled many of us were about this.

When the time came for a Q&A session it didn’t take long for it to be asked and BMW tried their best to explain that the i3’s range predictor will be so accurate that a proper SOC gauge isn’t needed. That didn’t sit well with the ActiveE drivers and the protest continued until the managers said they hear our displeasure and promise to revisit this, opening the possibility to adding the state of charge display before the US launch – or possibly just to quiet us down a bit and move on the the next topic!

BMW i3 - Where's the SOC? What's the state of charge? 54%? 56%? I guess it's somewhere around there but I want to know precisely. Every percentage point counts some days in an EV when you are stretching the range.

BMW i3 – Where’s the SOC? What’s the state of charge? 54%? 56%? I guess it’s somewhere around there but I want to know precisely. Every percentage point counts some days in an EV when you are stretching the range.

One thing I found interesting is that on the European i3’s, at least the one’s with the range extender option, there is a state of charge display. A BMW i3 forum member sent me the picture to your right as proof. However, here in the US that screen isn’t available since unlike in Europe, US customers will not have the ability to manually turn on the range extender once the state of charge dips below 75%. The inability to do so does make the range extender less useful, however how much less useful is a story for another day once I’ve had the opportunity to properly test drive an i3 REx with a depleted battery in range extender mode.

The point is, the car knows its state of charge and can display it for European REx customers, so why not just make the display standard on all i3’s and make everybody happy?

There it is! 85.5% state of charge - only US customers don't get to see it!

There it is! 85.5% state of charge – only US customers don’t get to see it!

Will this prevent me from buying an i3? No. Will it make the driving experience much worse? Probably not. What bothers me more than anything else is this is something the MINI-E and ActiveE were overwhelmingly in favor of and I don’t know how BMW missed it. The point of the MINI-E and ActiveE trials were to find out things like this so the i3 and future BMW electrics would be the best they could be. I hate to really harp on this so much but I’m really disappointed this was somehow overlooked. It’s not a little oversight, it’s a major omission to me.

When the Nissan LEAF launched back in 2010 it didn’t have a state of charge gauge and the LEAF owners were very disappointed. So much so that they complained continuously until Nissan added the state of charge gauge two years later.

How did BMW overlook this? It’s really baffling.

Categories: BMW


Leave a Reply

50 Comments on "Say It Ain’t So – BMW Omits State of Charge Indicator on US i3"

newest oldest most voted

So Tom,
You know I have asked before and GeorgeS and I want/need to know whether you are buying with or without the Rex? Do you know yet and has this influenced you? If you have the Rex this is really not a show stopper. If you do not then certainly it changes the issue. Want BMW consider burying it on another screen somewhere like the Volt does?

I agree that it’s a weird omission but don’t see this as big a deal as he does. Even an average efficiency remaining range indicator gives you a reasonable approximation of the SOC. Better yet is a remaining range estimate based on actual driving. The bar graph is pretty laughable. I didn’t expect BMW drivers to want dumbed down indicators like that.

Needless to say, I think Tesla got it right.

I saw that some BMW reps referred to the accurate miles remaing meter and the navigation knowing elevation and speeds on your planned route as being sufficient gauges.
They clearly have not thought this out…. Smarter nav is useless because most drives are not planned exactly . I rarely use nav , I mostly know where I’m going, and a SOC % is the most useful info I need.
I’d say 1 in 500 times I use the car I program the nav. You don’t need nav to get home from work, but you do need an accurate and precise SOC %!

I agree. I loved it when Apple finally gave our iPhones a SOC numeric readout and my 2013 LEAF’s SOC indicator is my default display.

Couldn’t you just use a bluetooth OBD2 reader and an ap on your phone or tablet, to access the SOC value?

That is like using a dip stick to see how much diesel is left in the tank… while driving! 🙂

The answer is no! The car has orders of magnitude more processing power than the whole Apollo program combined and not one but two high-resolution, high-color LCD screens.

Just display the freakin’ SoC in kWh and the instantaneous (1 second sample) and average efficiencies in Wh/mile.

Welllllll —- it’s first gen…. There will be some freakin’ sacrifices. I don’t see anything wrong with purchasing a scan guage even if you forego the Bluetooth and the app. You are, however, paying a boatload of money for a pretty small car that seats four and has a good number of limitations. This is why I don’t see i3 as anything near a value. To me, it’s more of a statement vehicle for folks who opt to buy them over – say, a Volt. Optimists who’ve driven the car use words like, “zippy” or, “sportier than I anticipated”, which leaves a whole lot still to the imagination. I’ve not seen anyone canyon carve with the thing or even hit the skidpad and toss it hard into any kind of a corner. If you bought a LEAF and a discounted Volt, you’d have more of a usability range IMO. It’s not nonsensical either, as $53,000 for both isn’t much different than what folks will see on the window sticker of an i3 with heat pump and ReX. The majority of buyers will still use i3 as a 2nd or 3rd city/commuter anyway. Sure, there are arguments, like 2 insurance bills… Read more »

I do this in my Volt w/my Droid and my Nexus. It’s not hard. And you can mount your phone/tablet so its visible just like a screen. In fact there’s all kinds of data that can be displayed.

But for the most part I just use the range predictor and battery indicator to see how much juice I have. The range predictor in the Volt seems to be very accurate.

Why is there 5 battery bars on one image and then 4 large bars under the other image?


Two different cars. 5 bars on the ActiveE and 4 on the i3.

The European i3 sounds really nice. The US version, not so much. The CARB rules are killing innovation.

weird, a government organisation sucking the life out of something…., if the government left more things alone(not all but thing more like energy subsidies), we would have been driving smaller and, there would have been a lot more EVs. stupid oil subsidies

Well Tom, if its any consolation there is also no SOC indicator on the chevy volt. Not a reliable one anyway. I can pull up supposedly the soc on my computer, but I can’t do it just driving along in the car. Its amazing how little info is told to you in the volt.

I do have one worse for you though. Ford’s Transit Connect EV conversion, a friend of mine bought. While driving it has a ‘gas’ gauge. But while charging, there is no indicator to find out how full the batttery is. Plus its good and slow at 3.3 kw. You’d think they’d put 6.6 kw in such a huge truck, especially for a fully BEV.

An SOC indicator is nothing more than an electronic analog holdover of an ICE fuel gauge. I would much rather have my ICE tell me how many miles I have left in the tank than how many gallons of gas I have left. Or, more accurately, what fraction of a full tank of gas I have left. I have to convert that information in my head, via estimated fuel economy, into applicable data that actually has meaning. The thing I want to know is can I make it to my next destination before having to refuel. I definitely do not care what fraction of a full tank it takes to get there. An SOC is the same kind of useless information if I have a vehicle that tells how many miles I can go. Even more so if I have a Driving Range Assistant with dynamic range map, which takes account of all relevant factors to determine the most efficient route: battery charge level, driving style, traffic conditions, and topographic features of the route. Let those remnants of ICE driving go and fully embrace the convenience that is possible with an EV and technology.

I disagree.

SOC indicators are like a common gas guage.
What good would a simple % guage do me for my current trip if I am making
several planned and unplanned trip. Knowledge is power and you want to know
how much “fuel” you have left in the tank at any given time.

Exactly, a gas gauge and an SOC are percent gauges. Useless data.

Why is that “useless” information?

If you don’t like it, then don’t use it. There is no need to remove a feature, which many find useful.

Tom, in light of Car and Driver’s report that a German BMW dealer source
indicated that North American i3’s with ReX won’t be here until July — would
this force your hand in going straight EV? That’s a lot of coin for an 80 mile
BEV any way you slice it.

If you waited for the ReX, perhaps the SOC indicator glitch will be solved
since those car’s delivery dates just may be pushed back. Some are
speculating that BMW is tweaking the performance parameters for our
market since that low-end SOC ReX mode seems wimpy for our roads.

Is the i3 starting to look like less of a genius move than they first
perceived to ANYONE out there yet? You still want to dish out THAT
kind of money and still have to mess with those funky rear doors?!

I just spent two days at the LA auto show systematically reviewing EVERY EV on display and there is nothing remotely close to the value the i3 delivers in terms of performance, safety and convenience features and technology. Way more safety features than the much pricier Tesla. For a while I got caught up by the Chevy Spark EV because it is insanely cheap. But when it comes to putting my family in it, the i3 wins hands down.

Fuel gauges were invented 100 years ago when there was no other technology available. They provide indirect information that tells you almost nothing you really want to know. Same with SOC. We now have GPS, google earth, cellular internet access, dozens of sensors and massive computing power on modern automobiles. Let all of that technology work for you. Dump your SOC and use the Range Assistant, it will do a much better job at telling you what you need to know.

Range assistant has no idea what you plan to do in the future. Climb mountains, run the heat or defrost, get on the freeway and do 80 mph; or maybe get off the freeway, coast down a mountain or turn off the heat.

An SOC readout is mandatory on an EV. I don’t know of a single modern car that doesn’t have a gas gauge. There are reasons for that.


All you have to do is tell it where you want to go and it will not only tell you the most efficient route to get there but it will account for all of the ups and downs and stops and gos and everything else including traffic conditions and it will be way more accurate than you estimating and guessing and calculating all of that stuff in your head.

I’m totally with you, Tom–an SOC indicator is an absolute necessity. I’m constantly wishing I had one on my Tesla Model S.

Isn’t it weird that the two most sophisticated electric cars–the i3 and the Model S–both lack an SOC gauge? Even the cheapest electric car out there, the Smart ED, has a nice little SOC dial. Admittedly the Volt and Leaf SOC 10-bar indicators are fairly crude, but they’re better than nothing.

Hopefully BMW will respond to your pressure, and maybe that will enlighten the folks at Tesla. Amazing that both BMW and Tesla can do so many things right, yet get the SOC thing so totally wrong.

Have you seen the BMW range assistant? It is better than anything the Tesla or any other EV has. Don’t get me wrong I am very envious of you owning a Tesla I wanted one myself for a long time and have been test driving them for a while. But an SOC is a hold over from 100-year-old ICE technology. We have much better technology now and the BMW range assistant is the best of the best.

I’m sorry, but there is absolutely no reason not to provide a simple percentage SOC meter at least as a display option. Certainly, it’s not perfect and is indeed quite simplistic. That said, at least two generation of EV drivers have demonstrated its usefulness, and have chosen to use this feature. Every auto manufacturer on the planet claims to have invented a better guessometer. While I personally appreciate these effects, and range prediction is certainly improving, an SOC meter is still a necessity. I’m not convinced by your argument that the meter is an anachronism and needs to be left out. That’s akin to saying that the windshield is a holdover from the gas car age, and should therefore be removed, and we should drive by what the computer tells us. Perhaps one day that will be true, but we are not there yet. The SOC meter is useful to many. BMW, please find a way to put it back in as a display option. Those that don’t like it, won’t have to look at it. What we did in the LEAF community was design a third-party meter, which plugs into the diagnostic port. I’m a big proponent of displaying… Read more »
What do you do with the SOC data? You take it and somehow, in an algorithm in your head, based on what you believe you know about the trip ahead such as distance, topography, road type (freeway or surface street) etc., you estimate each variable and then estimate charge per mile based on your experience and mash it all together into a decision about whether you will make it to your destination. Range Assist is more accurate on every one of the above variables than a human ever will be. If I want to know the distance to a location, I use google maps and I get an accurate distance within a tenth of a mile (528 feet). No human can do that. Range assist has that accuracy for every variable and it includes variables you don’t like actual traffic conditions. So Range Assist does everything you are doing in your head with more accurate data, more data and more accurate calculations. Just like google maps became the standard because it is better, Range Assist will become the standard. As an early adopter, you will want to integrate it into you driving lifestyle sooner than later. By the way, if… Read more »
Well, that’s exactly the point, the range prediction algorithm is not always better than mental math or personal observation. Especially not when running critically low on charge. Most DTE gauges will show you zero, some dashes or an exclamation mark when you have about 1 or 2% left. Good luck trying to figure out if and how you will be able to make it to charging station, which is 1.8 miles away. Without an instantaneous energy consumption meter and a state of charge meter, you won’t stand a chance to figure out how much you need to slow down to make it to that destination, and you will be squinting your eyes to see if there were any pixels left in the last remaining bar of the four segment charge display. That said, I am not an opponent of better navigation methods, and have described above how we worked hard to complement the DTE gauge Nissan offers in in the LEAF. I’m quite familiar with most of the DTE algorithms, and most of them are far from perfect. Additional information is both useful and welcome, and that’s what this discussion is all about. I believe that I have offered enough… Read more »

Wow you are working awfully hard just to drive a car. I am not going to squint my eyes or do anything like that, I am just going to glance over at the range assistant which graphically displays the radius of travel range and also displays the location of charging stations and drive to the one that is within that radius of travel range. Easy.

Well, I certainly hope that the distance to empty gauge, of what you call the range assistant, will tell you exactly what you need to know. Becasuse chances are that it won’t. That is the crux of the argument. Every car maker on this planet is ready to proclaim that they have reinvented the wheel. While I hope that it will come to pass one day, in the meantime, I have learned not go take such promises at their face value. Besides, what is harder, learning from observation and experience that a certain percentage of SOC will go a certain distance or slavishly entering every single destination into the navigation system? Without that step, the range estimate wildly inaccurate. And even when knowing where you are headed, the algorithm will not be able to take into account different driving styles. I can go 75 mph or 55 mph, depending on my range needs. That’s a difference of 85% in energy expenditure over the same distance. Good luck figuring that out automatically based on a short integration interval. And if you tell me that it’s easier to just charge up whenever the computer asks you, we’ll sure, if you can do… Read more »

Maybe you haven’t seen the BMW range assistant. It is a graphical display that shows your radius of range in all three driving modes, see it here:

“A realistic range estimate using navigation, battery, route topography and traffic data. This information can be shown on the car’s”dynamic range display” which provides an overview of all possible destinations. If a destination is out of reach, the car will suggest going into ECO PRO or ECO PRO+ mode to maximize the vehicle’s range by limiting the top speed and switching the heating / ventilation system into an energy-saving mode. If that still isn’t enough, the car can display public charging stations which can be reserved from the display.”

I certainly respect your “many EV miled” opinion and I learned a few things from the discussion with you. Let’s just say agree to disagree.

By the way my local dealer in Long Beach has i3s for test driving this weekend. I can’t resist the desire to go drive one again, for the third time.


I certainly respect your “many EV miled” opinion Tom, and I learned a few things from the discussion with you. Let’s just say agree to disagree.

By the way my local dealer in Long Beach has i3s for test driving this weekend. I can’t resist the desire to go drive one again, for the third time.


I never use my SoC meter. I use the non-granular battery meter. Why? Because I know my vehicle’s range and I know I don’t even come close.

Do many/most EV owners use 99% of their battery capacity on a regular basis? I can go as many as 4 days of driving without recharging my i-MiEV.