Does A BMW i3 Battery Upgrade On An Older Model Make Sense?


Here’s Why an i3 Battery Upgrade Currently Doesn’t Make Sense

BMW i3 With New 94 Ah/33kWh Pack Cutaway

BMW i3 With New 94 Ah/33kWh Pack Cutaway

The concept of upgrading an electric vehicle’s battery pack is certainly not a new one. In fact, it’s something that many EV owners have been vocal about wanting to see offered. So the news that BMW (regionally) would begin a battery upgrade program for their current i3 owners is good indeed, even if it may be something that isn’t really necessary, or practical – yet.

The big news in BMW i’s May 2nd press release was, as expected, that BMW would be upgrading the i3’s battery cells from 60 Ah to 94 Ah. This means the 2017 i3 will have an EPA range of 114 miles, up from the current 81 miles per charge. These new battery cells are physically the same size as the currently used cells, but can hold 50% more energy and are only slightly heavier. About halfway down the press release, this interesting bit was stated:

Retrofit Program: The Battery Can Be Exchanged Optionally

“The Main focus at BMW i is on sustainability. The consumer is given the assurance that his (her) BMW i3 can be adapted to the latest technical developments in a resource-saving way. This is safe-guarded by the flexible LifeDrive vehicle architecture. The BMW i3 is the first automobile in the premium compact segment in the world to have been designed from scratch as a purely electrically powered vehicle. This design also includes retrofitting new battery technologies.

With the introduction of the new 94Ah battery, BMW gives BMW i customers the opportunity of retrofitting their purely electric BMW i3 (60 Ah) with the new 33 kWh battery as part of the a high-voltage retrofit program. This program is available in select markets. The 22 kWh batteries traded-in by customers are used to build stationary storage battery modules thus starting their second life. This effectively proves how sustainable BMW i technology is across its entire production and service life cycle.”

New 2017 BMW i3 In White

New 2017 BMW i3 In White

I highlighted “select markets” because it appears that BMW AG is allowing its regional offices to decide if they want to participate in the retrofit program. BMW of North America and BMW UK have both declined to participate at this time.

It’s believed that is because the cost of the retrofit is high, and since the cars are still relatively new, they believe few customers would elect to upgrade. While there hasn’t been any official cost announced for the upgrade yet, I’ve had people in European countries that will participate contact me, and tell me they were quoted roughly $8,000 US. I’ve also seen people in i3 Facebook groups discuss a number similar to that, so I believe $8,000 is likely accurate.

This is actually pretty close to what I predicted an upgrade would cost, and why I’ve previously said it will be very hard for BMW (or any manufacturer for that matter) to offer a reasonably priced battery upgrade as new, better battery cells become available. There’s a reason why no OEM has offered a battery retrofit program for a currently-available model like this.

Tesla Roadster Battery Swap Will Set You Back Almost $30,000

Tesla Roadster Battery Swap Will Set You Back Almost $30,000

The exception being Tesla, which has offered a battery upgrade option for their Roadster owners to consider, however it costs $29,000 and was offered three years after Tesla sold their last Roadster. Tesla does not offer battery retrofit upgrades to vehicles that are currently in production, namely the Model S and Model X. Roadster owners were generally underwhelmed by the upgrade offer, and while it’s unclear how many took advantage of the program, it’s most certainly a very small number.

The only other upgrade comparison worth noting is that Nissan will allow LEAF owners to replace their pack with the same size 24 kWh battery for $5,499. They won’t however, allow a customer with a 24 kWh to upgrade it to the new LEAF 30 kWh battery. This isn’t a battery upgrade program since Nissan only gave customers the option to replace their battery with the same one, albeit new pack. Offering a battery pack upgrade isn’t an easy thing to do, it’s not just a matter of swapping the modules with the new cells. There’s plenty of reasons why BMW is the first OEM to offer this on a currently available model. In fact, Transport Evolved covered this topic in depth with this post a couple months ago.

Nissan Has A Battery Swap Program For Replacement Packs

Nissan Has A Battery Swap Program For Replacement Packs

So BMW’s retrofit program is indeed something unique, and hopefully something the other OEMs copy. The fact that BMW uses the traded in battery packs to build stationary energy storage modules opens up another question: Who’s going to use them? Will BMW sell them to a third party or will BMW refurbish them in house and sell the battery storage unit themselves, ala Tesla’s Powerwall?  I’d love to upgrade my battery pack in about three more years when I have 130,000 miles on it, and get my old battery back from BMW, refurbished and ready to be used in my home.

BMW hasn’t elaborated on exactly what they plan to do with the “stationary storage battery modules” made from the traded-in packs, but this is an option I believe and may very well end up being what they do.

Personally, I like the idea of getting my car’s old battery back to use in my home. It would really expand the sustainable life-cycle model that I’d like to employ. It would also be a cool conversation piece, especially when someone asks me sarcastically, “Where do you think those EV batteries go when you replace them?” Intimating that they will end up in a landfill, leaking toxic acid which is a common misconception about high voltage lithium ion batteries used in EVs. I would be able to answer, “After powering my car for 130,000 miles, I replaced the battery pack with a new one that now allows me to drive twice as far as the original pack. I then took the original battery pack and put it in my basement where it will be used for about a decade, storing energy generated from my solar array, so now I’m always driving on sunlight, whenever I plug in to charge.”

2017 BMW i3 Battery

2017 BMW i3 Battery

So why doesn’t battery retrofit make sense now?

While this sounds great, the truth is it’s still a little premature to get excited about the retrofit program. The i3 is only about two years old, and even the earliest i3s delivered in Europe aren’t even close to the point where they need a battery replacement yet. Here in the US we just passed the two year anniversary of the first i3 delivery this week. It just doesn’t make sense to replace an EV battery which is only two or even three years old, especially since the vast majority of i3’s are leased. I believe this is why BMW of North America and BMW UK both decided against offering the battery upgrade program at this time. It’s not that they don’t think battery retrofit is a great idea, it’s just not time yet.

I took delivery of the first i3 REx in the US on May 25th, 2014, so I’ve owned my i3 for almost two years now. I have a little under 50,000 miles on the odometer and so far my battery has about 94% of its original capacity. I have one of the highest mileage i3s in the country and still have 94% battery capacity; why would I, or anyone for that matter. want to buy a new battery pack now? As I mentioned above, I definitely plan to upgrade my battery at some point, but I first want to get value out of the pack I already paid for. If I continue driving at the same rate I am now, which is 25,000/yr, then in three more years (2019) I’ll have 125,000 miles and will probably be ready to upgrade.

Coincidentally, in 2019 BMW’s battery supplier Samsung SDI, is scheduled to release their next generation of automotive lithium ion battery cells, which will be 125 Ah. The cells BMW will be using in the 2017 i3 are 94 Ah, replacing the 60 Ah cells I have in my i3. I’ll most likely skip the 94 Ah generation and upgrade directly to the 125 Ah cells once they are available, and that’s exactly what I expect most 1st generation i3 owners will do. Upgrading to the future 125 Ah cells will effectively double the car’s range, as opposed to the 40% increase in range the 94 Ah cells are delivering.

That’s how battery retrofit makes sense. Paying $8,000 to replace a two year old battery just to add 35 miles of range simply doesn’t add up, and it’s why most markets won’t offer the retrofit program just yet. However replacing a battery with 125,000 – 150,000 miles, after it’s been used 5 – 7 years or longer, and doubling the range of the car when it was new does make sense, even at a cost of $8,000 if you plan to keep the vehicle long term. Plus, the cost of the cells will most likely continue to drop, and the replacement pack will probably cost less in three years than it does now, even though you’ll get better batteries.

I really like that BMW AG is starting the program now, even if it’s not likely to get many takers. This will allow them to work out any potential problems, gradually improve the program, and in a couple of years time when the early i3 owners start inquiring about it then BMW will be 100% ready. By 2018 I expect most major i3 markets will be participating in the retrofit program, just as the demand for battery pack replacements begin to rise.

*Editor’s Note: This post appears on Tom’s blog. Check it out here.

Categories: BMW


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48 Comments on "Does A BMW i3 Battery Upgrade On An Older Model Make Sense?"

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I believe a battery upgrade to the upcoming 120 Ah batteries makes a lot of sense to i3 owners. It would give them an EPA range of nearly 160 miles.

An upgrade to the 94Ah batteries makes little sense.


plus it shows BMWs commitment to electrics…

If Nissan, BMW or other car makers gives me $4000 on an older lower capacity battery for an $8000 new higher range battery, I would be there. They can refurbish it then sell it as a wall unit.

As Tom points out often, how much? When that battery is available, price might be more than leasing new i3 (or Bolt or whatever). Currently, i3 lease seem to run about $8K for 2 years (see ev-vin blog)

If the battery had died (10 years later?) and you must replace, that might make sense to upgrade. But by then, would you drive such old car or just upgrade to newer model? Battery upgrade makes little sense unless you have sentimental value attached to current car, and very few do.

it make sense,if i keep the old battery(it is possible by nissan)and use the old battery as solar battery,or use the cells in a boat or other vehicles,or use the old battery to double up the range of a e-nv 200

“Tesla does not offer battery retrofit upgrades to vehicles that are currently in production, namely the Model S and Model X.” Tesla did offer to retrofit larger batteries into the Model S, but I don’t know whether this option is still available. There was some talk in the forums that Tesla also had to upgrade/modify the suspension to handle the additional weight of a larger battery pack. David Nolan from GreenCarReports upgraded from a 60 kWh (10 months old and 11,000 miles) to a new 85 kWh battery in his Model S for a net cost of $18,386, including parts and labor, which works out to $735 per additional kWh. His Model S also received a speed/power boost as well. From GreenCarReports: “The cost breakdown looked like this: Price of the new battery was $44,564. The trade-in value of my old battery was $29,681–a number arrived at by discounting its new list price of $37,102 by a 20-percent ‘restocking’ fee.” “The net cost to me of the new battery was $14,883. Adding five hours of labor ($600), minor parts ($125), the battery shipping cost ($1,520), and sales tax ($1,257) brought the grand total to $18,386.” I don’t see any charges… Read more »

i3 owner here, love the car, but I don’t really care about the upgrade on my i3.

Everyone got excited when there is an upgrade, BMW will eventually announce the cost of the new battery, then everyone will get less excited about it because it doesn’t make any financial sense.

i3 is a great daily car, but not for cross country, the upgrade doesn’t make majority of the owners drive further, we still drive the same distance everyday, and we still can’t drive cross country.

Upgrade is great for new i3, not existing i3.

Tom’s right on economic considerations, but this early move by BMW should raise buyer confidence tremendously, and if my car were to pole-vault over a chunk of debris on the roadway and require a battery replacement, I’d love to have an upgrade option. Knowing that I could upgrade my range after it degrades in 100,000 miles or so could make the difference in which vehicle I purchase (not lease).

Yes, this is the use-case.
If you need a new battery, because of accident, you should be able to upgrade.

They might as well offer the upgrade even though they don’t expect any customers to take advantage of it, simply for the PR boost.

Using car batteries that are depleted to 80 or even just 70% of their new capacity for stationary purposes is complete nonsense, as their useful CYCLE LIFE is over. Why do people think they can keep on cycling them hundreds or even thousands of times more as stationary batteries with any really usefull capacity?!
So NOW would be the perfect time for replacing i3 battery packs with the new bigger ones, as the old packs would still carry some useful CYCLE LIFE in them for stationary purposes.

Car batteries need to be tuned to high power density combined with medium cycle life, whereas stationary batteries need to be tuned to extemely high cycle life at medium power density. Both at the same time cannot be had at this point because cycle life and power density are diametrcial ends of the same set of battery characteristics, i.e. one is always the tradeoff of the other.

Backup batteries don’t.
You’re talking about energy-price arbitrage.

MEroller said: “Using car batteries that are depleted to 80 or even just 70% of their new capacity for stationary purposes is complete nonsense, as their useful CYCLE LIFE is over.” That turns out not to the case. “Why do people think they can keep on cycling them hundreds or even thousands of times more as stationary batteries with any really usefull capacity?!” Perhaps it’s because plenty of people have done exactly that, and have found it works just fine. There’s no “cliff” off which battery capacity suddenly drops after their capacity is reduced to 70-80%. They still do have that 70-80% capacity, so why not continue to use it up until it’s much closer to actually being gone? “Car batteries need to be tuned to high power density combined with medium cycle life, whereas stationary batteries need to be tuned to extemely high cycle life at medium power density.” It’s true that EV batteries need to be optimized for different characteristics than stationary batteries. But you seem to think that the differences are extreme, whereas in reality those differences are just a matter of degree. Sure, using EV batteries for stationary storage isn’t the optimal use. But what other… Read more »

Someone give this man a gold star.

not really, problem is internal resistance that becomes high to be usable in cars which need peak ~3C rates, for storage it is probably about 0,5C

Previous post from another forum– My thoughts on the i3 Rex and sustainability: –33 Kwh is “right-sized” for the i3 Rex. –33 Kwh i3 Rex might be considered “crusher proof”. (and perhaps the greenest car on the road): *Composite body — won’t rust, should last for 50 years. *647cc rex + generator, only runs for a couple thousand miles a year — should last for 50 years *33 kwh battery — at a likely future replacement cost of, say $200/kwh, then the $6,600 [$or 8,000?] pack replacement cost (every 8, 10, 12+ years?) is manageable with the added bonus that a marginal battery pack can be supplemented (limped along) with the Rex until it’s a “good time” to replace the battery. Underbody mount minimizes labor costs. So, .. … the sustainability concerns of the car buying public might be best served burning appox 50 gallons a year or so in a decades lasting i3 Rex vs. sending a fully highway capable BEV to the crusher at year 8,10,12 (?) ————– The concept of “new age personal transportation” evolving into a “too expensive to crush” (i.e replace every 10 years) is not without precedent. General aviation in the United States has… Read more »

Well SpaceX is leading the way with the rocket boosters, it’ll be interesting to see a 30 year old Model S or 3.

Car makers need to think upgradable. I think its a reason why the Nissan LEAF has such poor resale. If it had 30kwh option it would be much more interesting.

A Leaf with a 30 kWh battery pack would still lack any battery active thermal management system (TMS), and would still be subject to premature aging of the batteries.

And I think that, more than anything else, explains the poor resale value of the Leaf.

At some point, Nissan is going to have to start putting a TMS into its BEVs. The only question is how long they’re gonna keep putting that off.

Has anyone seen premature degradation since 2013? I mean it is still early but I have a early 2013. No bars lost – 35k miles. North Carolina climate.

TMS may not be necessary after all.

Obviously 2011 and 2012 had issues that were fixed for 2013. It isn’t just about TMS.

Last comment – I have a 15 Model S. I don’t think the TMS has ever run except perhaps during supercharging. It needs battery at 100+ to run and I don’t think it has ever gotten there. Certainly ambient gets there every once in a while but battery is probably still not there. Nights are rarely above 80 and 100 lasts usually for a couple of hours. Check the specs – the S doesn’t do what a Volt does – that is keep the battery at 70. It lets the battery get to 100+ when stationary

Arizona is a different case.

I had a 2012 in Virginia that didn’t lose its fist bar until the 35th month – so I wouldn’t breathe easy yet.

It is more an upgrade to five seats, normal doors and a full trunk that is badly needed than a battery upgrade. It is an upgrade from i3 to i5 that would make the most sense.

Boy that was a long one. But finally:

“Coincidentally, in 2019 BMW’s battery supplier Samsung SDI, is scheduled to release their next generation of automotive lithium ion battery cells, which will be 125 Ah. The cells BMW will be using in the 2017 i3 are 94 Ah, replacing the 60 Ah cells I have in my i3.”

Those were the words I was after.

I have a suggestion Tom.

Give up on BMW they are as bad as GM. They talk the talk but only Tesla wants to make it happen NOW.

Hopefully you you got your TM3 dep in.

I think the so called need for upgrade by few EV fans are overblown.

Most of the time, it doesn’t make sense for manufacturers. The cost of battery, especially used one goes downs significantly. An upgrade wouldn’t make cost sense. If you charge too much, nobody will take that offer, if you don’t charge enough, then it is a loss/loss business. Plus, from R&D side, the company has to make sure the pack fits and all the FW works. It is just a hassle to support that in the long term for a very small market.

I dunno. How easy is it to drop out the battery and replace it? If it is easy then maybe they can get people to pay a pretty penny for it, take back the old battery, and turn it into a residential battery.

I think if upgrade was cheap enough I would get it. But my biggest question is if you could raise the range of a BMWi3 or a Mitsubishi i-miev by a hundred miles then I would buy a upgrade. But if the upgrades only add 30 miles or 50 miles that really doesn’t equal much.

Another question is how many miles are driving the car a day and how many times do you need to quick charge to go the miles you need a day.

Better than GM/Nissan, worse than a Tesla.

The i3 upgrading to just 114 miles for a 2017 model is unacceptable. i3 needs an upgrade to 200 miles. It’s not like they didn’t see that range becoming the new norm at the $42k price they are asking for the EV.

114 mile range has the i3 competing with the current upgrade Leaf, and not the new Bolt or Model 3.

Also at that short range, an upgrade won’t help the massive depreciation it the i3 will take, when the 200+ mile bolt and especially Model 3 hit the market. It’s going to be a hard sell to move a $42k+ i3 at 114 miles, when a Model 3 is at $35k and over 200+ miles or range.

So any additional investment in the current i3 would be just increasing the current and accelerating loss as new 200 mile models are launched.

Actually with battery and component prices dropping, the new model with 114 miles should actually cost less than the current 81 mile version.

You make some good points. Range per dollar isn’t everything, though. Almost, but not quite. The i3 sells at all because it has luxury and unique features. Some people are OK with 100 mile range and place a high importance on luxury and curb appeal. Not me, but some people. I think the i3 will continue to sell.

“Why would I, or anyone for that matter want to buy a new battery pack now?”

Uhmmm .. Maybe so I can drive 50% further on a single charge?

If car companies cultivated brand loyalty at the start of the expanding EV market they would sell increased kWh replacement packs at the same price as the original kWh battery that is being replaced. They would have the original pack returned as a prerequisite to the upgrade. This loss leader would only affect a total of less than 200 000 total first gen vehicles in Nissans case and only a fraction of those would get upgraded until the standard packs reach over 215 miles. The future sales, brand loyalty built combined with consumer confidence would pay back in the long run. Who wouldn’t buy a second vehicle from a company you know will look after you after you took a risk on their car. But… The odds are good they will ride it out until the first gen disappears.

Thanks, Tom, I appreciate the depth.

Sorry to sound like a broken record, but updates on your wrap? Tried a search on the blog, but am famously challenged in that regard, lol.

Hi Tom,

I’ve been reading some of your articles on the i3 and even saw an article from a few years ago where you had recorded the battery’s capacity over time with many log entries. I was wondering if you knew of anyone or any website that had collected battery capacity (or range) data from many vehicles over time for the i3 (or any other electric vehicles)?

Hi. I3 REX owner here. When trying to get a price from local BMW dealer for upgrading battery, I was told that its not possible to upgrade the battery in the REX version of the I3. Anybody who might know a fix around this ?

Claus, would be interested on any further information you get regarding this – I’m a 2014 i3 REX owner too and would be very interested in a battery upgrade to further extend range before REX is required

I was guestimated $32,000 by BMW San Francisco to replace the 60ah battery on my 2014 i3 with a 120ah battery. The cost associated with the battery included having to replace the computer and sensors. The BMW rep encouraged me not to take this route.

I have a 2014 BMW I3, with about 30000 miles on the clock. The theoretical range would have been 80 miles in the summer when new. At 5 years old, on a typical Glasgow winter’s day it is about 40 miles. If BMW do not offer new battery retrofits soon, then 3rd party suppliers will fill the gap. Get a grip, BMW, it’s a super city runabout, with plenty of presence. Give us the opportunity to use it.

Companies will eventually realise this is a major point to stop estupid depreciation EVs have. You can buy a i3 with less than 3 years for half the original price.