Battery Options for the 2017 BMW i3?

A Samsung employee shows of one of the new 94Ah battery cells which I predict the 2017 i3 will boast

Ever since last October when BMW CEO Harold Krueger stated that the 2017 i3 would have an increased electric range, there's been speculation on how they would accomplish it. While BMW hasn't made any official announcements yet, it's widely believed that BMW will be using the new Samsung 94Ah battery cells for the 2017 i3, which I first speculated here, back in November. 

The current i3 uses 96 Samsung 60Ah battery cells which are 3.75v ea. This adds up to a total of 21.6kWh (96 x 60 x 3.75= 21.6). The new 94Ah cells are the same physical size and voltage so an upgrade to these cells would mean BMW could use the same modules and battery tray, greatly reducing the cost as compared to engineering all new packaging for the new cells. Therefore, the new pack should increase from 21.6kWh to 33.8kWh (96 x 94 x 3.75 = 33.8). If the weight of the cells is the same, that should increase the BEV i3's range from the existing 81 miles per charge to approximately 125 miles per charge and the i3 REx's range from 72 miles per charge to about 112 MPC.

The battery pack of my i3 REx. It was removed to replace a faulty battery heating element. 

So we know for sure that the 2017 i3 which begins production this summer will have increased range from improved battery cells, and we believe we've figured out which cells BMW will be using. The next logical question then is:  Will that be the only battery available for the 2017 i3, or will BMW also continue to offer the current 60Ah cells as a lower cost battery pack option? We say the latter.

As a comparison Tesla has always offered different battery pack options for the Model S. That, along with direct sales and the Supercharger network been part of the fabric which has made the Model S so appealing to so many people. But there is another example of an OEM offering battery size options which is an even better comparison, and that's Nissan. Ever since the Nissan LEAF launched in late 2010, it had been fitted with a 24 kWh battery pack. Just past Fall Nissan added a 30kWh battery pack as an option. The entry level "S" model still has the 24kWh battery pack, but if you want the higher level SV or SL trims, you also get the new 30kWh battery pack. 

BMW could do something like what Nissan did and continue to offer the 21.6kWh battery pack, but only on a base i3, to offer a lower cost option. Or they could do like Tesla does and simply allow the customer to choose the battery size they want like any other option. This will however drive dealers nuts because they'll now have to stock four different i3's. Some dealers are already having difficulty deciding how many of each of the current two versions to stock, so four different versions of the i3 definitely won't make their life any easier.  I am however, going to predict this is indeed what BMW does, and if I am correct, here's the 2017 i3 options that will be available as early as this September:

BEV with 21.6kWh battery and 81mi electric range

REx with 21.6kWh battery, 72 mi electric range & 74 mi additional gas range (39mpg x 1.9gal)

BEV with 33.8kWh battery and ~125 mi electric range
REx with 33.8kWh battery, ~112 mi electric range & 93 mi additional gas range (39mpg x 2.4gal)

Note the gasoline range on the 33.8kWh i3 REx increased from 74 miles to 93 miles. That's because in the US, BMW reduced the amount of gasoline available on the car to 1.9 gallons, even though the  fuel tank is actually 2.4 gallons. European customers have had access to the full 2.4 gallons all along, and will continue to do so. The reduced gas availability in the US was so the car would be classified as a CARB (California Air Resource Board) BEVx vehicle, giving BMW the maximum amount of the valuable ZEV credits, and qualifying the i3 for additional state rebates and tax exemptions. However, with the larger battery and longer all electric range, the i3 REx can now utilize the entire 2.4 gallons and still have BEVx designation, so I see no reason why BMW wouldn't remove the gas tank restriction and give access to the full 2.4 gallons. That would increase the overall combined range of the i3 REx from its current 142 mi to 205 mi. 

With the battery tray cover removed, you can see the eight distinct modules that make up the i3's battery pack.
Each module contains twelve 60Ah Samsung battery cells. 

Of course we're still just speculating here, and as we draw closer to the beginning of production for the 2017 model year i3 BMW has been as tight lipped as always on new or improved models. Perhaps the announcement will happen next week at NYIAS, or BMW may wait until closer to the 2017 launch as to not really kill sales of the remaining 2016 i3 inventory. In any event, the improved range will be a welcomed improvement for the i3, if not a necessary one. The new 30kWh battery pack of the Nissan LEAF is only a temporary improvement, as it's been strongly rumored that the 2018 LEAF may have a 60kWh battery. That, coincidently matches the 2017 Chevy Bolt's 60kWH battery pack, and that EV will boast a 200 mile all electric range. Then, in 2018 the Tesla Model 3 will launch, and offer a 200 mile range for about $35,000. So I'm guessing the next i3 range boost will have to happen in 2018 as a 2019 model, perhaps when the 2nd generation i3 is released. 

I'm sure BMW realizes they need to continuously improve the battery in their EV's if they want to be competitive in this space, and this LCI refresh for the i3 proves that BMW isn't going to sit idle and let the competition eat their electrons for lunch. 

bmw ceo harald krueger

BMW CEO Krueger revealed plans to increase the i3's range in 2016

It's no secret that if BMW wants the i3 to continue to remain relevant they will eventually have to increase its all electric range. In fact, in about a year there will be no less than two electric vehicles available in North America that have double the i3's all electric range and also cost less. Nissan will be launching the second generation LEAF, and Chevrolet will bring the Bolt EV to market by the end of 2016 and they are both rumored to have approximately 200 miles of electric range.

I think it's fair to say most people expected BMW to up the i3's range to stay competitive, but when they would do so was not known. Until now. BMW CEO Harold Krueger in an interview with Die Zeit recently said this about the topic:

“Battery cell technology continues to evolve. The range of the i3 will be increased in 2016. A further technological improvement is to be expected in three or four years: Then you’ll be able to go twice as far on a single charge without any further increase in the weight of the battery."

This is the first time anyone from BMW has offered a clear statement about increasing the range of the current i3. Personally, I didn't expect this yet, but welcome the news. I had always maintained that the i3's range would be linked to the progress made by BMW's battery partner, Samsung SDI. So the news that the MY2017 i3 will have increased range is interesting as well as exciting. It's interesting because Samsung has maintained that they wouldn't be bringing the next generation of large format, automotive grade batteries with increased energy density to market before 2018 - 2019. See timeline produced by Samsung SDI below:

Samsung SDI Battery Technology Roadmap

So the question is: How is BMW increasing the i3 range? Here are some possible explanations:

1) They are sourcing higher energy density batteries from other suppliers. This could very likely be the answer. The i3's 130 kW/Kg battery cells are not nearly as energy dense as the cells Tesla uses for instance. BMW could have a partner to supply them with cells which have considerably higher energy density and accomplished the increased range using the same battery tray as the current i3.

2) Samsung SDI provided BMW with a battery which is incrementally better than the existing cells they provide BWM with, but not quite as energy dense as the cells they plan to have in three or four years, according to their technology roadmap. Again, this would allow BMW to use the current battery tray and not need any major structural re-engineering. 

3) BMW redesigned the battery tray to accommodate more battery modules, or used the area where the range extender goes to add a second, smaller battery pack. Either of these options would have required a lot of engineering, testing and validation. I just don't see BMW doing either of these for a mid-cycle refresh. Certainly when the next generation i3 comes out in 2018 or 2019 there will likely be new redesign of the battery tray area, but not for a refresh, it's just too expensive to do that only two years after the initial launch.

Another benefit of the increased electric range will be increased gas range for the REx i3s in the US. Unlike in Europe, the US i3 must have a shorter range when driving on gasoline than it does on battery alone. This is a complicated issue which is tied to the amount of ZEV credits BMW gets for every i3 they sell, but in short by increasing the i3's all electric range, they can then allow the gas range to increase and still qualify for the maximum ZEV credits they get. The current i3 REx is EPA rated at 72 miles per charge and the range extender's gas tank is software limited to 1.9 US gallons which provides another 70 miles of range. If BMW were to increase the i3's REx's electric range from 72mpc to 92mpc. They could then allow US customers full use of the 2.4 gallon gas tank, and the combined range would go from about 142 miles to roughly 182 miles.

BMW employee working on an i3 battery pack assembly

Krueger was also asked if current i3 owners would have the ability to upgrade their cars with the new batteries and his answer was: "We are currently looking into that." Personally I believe that will be possible, but not economically viable, for now at least. I know current i3 owners will be asking about an upgrade but it just doesn't make sense to replace a battery pack that is two years old for just a little more range. I think it's more likely that in four or five more years when some of the original wave of i3 owners have 120,000 to 150,000 miles on their car they will be looking at the next generation of battery cells which will be available and these "new" battery cells will already be obsolete. I would be surprised if BMW didn't engineer those new cells to fit in the same modules the current i3 uses, so a complete replacement with the upgraded battery cells would then be possible.

What effect this will have on i3 sales from now until this new longer range i3 is available is unknown, but there is at least some comparable data to use. Both the Chevy Volt and the Nissan LEAF launched in late 2010 and are just now releasing upgraded range models. The Volt is a complete redesign and the LEAF is doing more of what BMW is now by keeping basically the same vehicle and offering it with an incremental longer range. The 2nd generation LEAF which will be completely redesigned and offer much more range won't be available for about another year. In both cases these cars experienced greatly reduced monthly sales in their final months as customers waited for the new model with longer range. Like Nissan and Chevrolet, BMW will likely have to offer some favorable financial incentives to clear the remaining 2016 stock once the new battery i3 is nearing availability meaning this should be a good time to pick up an i3 for a great deal.

In any event, this is all great news. It further proves BMW's commitment to electric cars and their willingness to upgrade the i3 as battery technology improves.