Rimac Automobili invents the Croatian auto industry

Detroit is gradually losing its position as the epicenter of the auto industry. Nowadays, news of cutting-edge developments is more likely to come from Silicon Valley, Europe or China. The Eastern European nation of Croatia is pretty far from the centers of automotive power, but it’s here that a highly innovative firm called Rimac Automobili is building electric supercars.

The company was literally born in a garage in 2009, in the small town of Sveta Nedelja, just outside Zagreb, and named for founder Mate Rimac. It began attracting attention within a year, as a test mule based on a BMW M3 started winning races against legacy gas-powered cars (the e-M3 went on to set five Guinness and FIA world records for EVs). In 2011, the company showed its Concept_One electric supercar at the Frankfurt Motor Show. In 2014, the Concept_One achieved worldwide visibility as the official Race Director Car for the Formula E racing series.

Let’s get the inevitable comparison with Tesla out of the way. Like the young Elon Musk, Mate Rimac has big dreams and a clear vision, and he has accomplished things in a short time that establishment figures would have said were impossible. In a country that had no existing auto industry, Rimac has built a company that’s selling cars and components around the world, and has been recognized as a great national asset.

“We are a true engineering company, with about 50% of our 190-person team devoted to engineering and design,” founder and CEO Mate Rimac told Charged. “A major challenge was to build that team in a country that never had a car industry and has only a few high-technology companies. That meant we had to go through a lot of trial-and-error iterations and learn from our own mistakes. That process bonded our team and created a family.”

Rimac EV 1

Rimac has been voted the best employer in Croatia, and is one of only a few high-tech manufacturing companies in the country, so it attracts the best talent in the industry. “What the local workforce lacks in industry experience is made up by their enthusiasm and drive,” says Mate Rimac.

Rimac is following the time-tested strategy of developing technology for a high-priced, low-volume product, then using the lessons learned to build a higher-volume model. However, unlike the Californians, the Croatians have no plans (yet) to expand to the mass market.

The company revealed a production version of the Concept_One at the 2016 Geneva Auto Salon. Production will be limited to 8 units, but the company is working on a new, higher-volume model, to be unveiled in 2017. “We are a supercar manufacturer, so don’t hold your breath for a high-volume family car, but we do plan to go in the hundreds of units territory,” Mate Rimac told us. No details of the next-gen model are on offer at the moment. “We have decided to unveil new models only when they are ready for production and not as concept cars.”

concept_one_04_dynamic_151242

If you want something done right…

Rimac does not follow the usual auto industry practice of contracting with outside suppliers to design and manufacture components. Almost everything that goes into the Concept_One is developed in-house, and built right in Sveta Nedelja. Perhaps this policy was partly born of necessity (automotive suppliers are few in Croatia).

Rimac’s web site explains its philosophy thus: “Painstaking attention to every detail requires high quality, which can best be maintained and controlled if the engineering and manufacturing teams are under the same roof. Thousands of metal, electric and carbon fiber parts have to be manufactured, assembled and tested for each Concept_One. Even the tools, jigs and molds are designed and produced by Rimac Automobili.”

“At our core, we are a technology company,” says Mate Rimac. “Most technologies and components that you can find in our car are developed and manufactured on-site in our facilities. Other than the obvious electric vehicle components such as battery systems, we are also manufacturing all composite and metal parts, electronics, infotainment, chassis, suspension components, etc. in-house. We are one of the few places in the world where you can start with a blank sheet of paper and raw material and design and produce a whole car in one facility.”

Spreading the gospel

Rimac also licenses its technology and engineering services to other manufacturers. “We provide a wide range of products and services to our customers,” says Mr. Rimac. “We are supplying components such as batteries, ECUs, and infotainment systems for some projects, while for others we handle the full vehicle development program, including small batch production runs for a range of applications and industries – from supercars to vessels to wheelchairs.”

Many of these collaborative projects are top secret, but at least two are anything but.

The Koenigsegg Regera, the brainchild of Swedish supercar designer Christian von Koenigsegg, is billed as the world’s most powerful car. With a V8 engine and two electric motors cranking out 1,500 hp of total power, and 2,000 Nm of torque, few would argue. Rimac supplied several components for this work of automotive art, including a 9.27 kWh battery pack that can deliver 500 kW of power and absorb 150 kW during regenerative braking, and weighs only 115 kg.

Rimac also collaborated with Monster Sport to build a custom car for the Pikes Peak International Hill Climb. Legendary driver Nobuhiro “Monster” Tajima drove the E-Runner Concept_One to win second place overall (EVs and ICEs) in 2015 and fifth overall this year.

Rimac

Multiple motors, one team

Designing things in-house enables Rimac to maximize the advantages of a native-built EV. The Concept_One’s powertrain and chassis were developed in parallel by engineers working within the same team. The resulting automobile boasts a high degree of integration among components, near-perfect weight distribution and an extremely low center of gravity.

EV designers are discovering the advantages of using multiple motors – after all, electric motors are compact and inexpensive compared to those noisy, belching things called ICEs. Whereas Tesla’s premium models use two motors, the Rimac supercar has no less than four permanent-magnet oil-cooled motors (designed and built in-house, of course). There are two 500 kW (peak) motors in front, and two 600 kW units in the rear. All four deliver 12,000 RPM at up to 97% efficiency.

Rimac

“The Concept_One’s powertrain is divided into four sub-systems, each consisting of one motor, inverter, and a reduction gearbox,” Mate Rimac explained to us. “Each of the systems drives one wheel, completely independent one from the other. Sophisticated ECUs control each of those systems using the input of many precise sensors placed all over the car. This architecture allows a new approach to vehicle dynamics, which is called Rimac All Wheel Torque Vectoring (RAWTV). We can control the torque on each motor, and thus on each wheel, 100 times a second. The result is incredible control and adaptability of vehicle behavior, a high level of safety and usability in every condition for all kinds of skills, maximized regenerative braking and fine-tuned traction control.”

The RAWTV system calculates the optimum torque for each wheel, functioning as both traction control and stability control. It also controls the 4-wheel regenerative braking of up to 400 kW, and the carbon-ceramic brakes. Rimac says that RAWTV can distribute the brake force faster, more smoothly and with greater precision than conventional ABS systems, ensuring maximum vehicle stability.

Rimac

The settings of the RAWTV system can be adjusted to change the handling of the car. Driving modes include Comfort, Control, Track and Drift mode, and drivers can also create their own custom settings.

What are the pros and cons of Rimac’s 4-motor design compared to an in-wheel hub motor? “In-wheel hub motors add unsprung mass that results in higher stress to suspension components,” says Mr. Rimac. “Our motors sit low and inboard, close to the center of the car, which we consider to be better for vehicle dynamics. In-wheel motors have to run at the same speed as the tires, which is a limiting factor. High-speed motors tend to be lighter, so gearing the motors up to high RPMs gives weight advantages. While there are many advantages to a four-motor setup, it brings a high level of complexity in the development process and requires a talented vehicle dynamics and control software engineering team to get the most out of the system.”

Shifting gears

Most EVs use a single-speed transmission, but Rimac points out that this forces designers to compromise between acceleration and top speed.

Each of the Concept_One’s four motors is coupled to a proprietary gearbox system. While the front motors feature single-speed gearboxes, each of the rear motors has a two-speed double-clutch gearbox. A proprietary carbon fiber double-clutch system with Formula 1 clutch disks enables either extremely fast or smooth and comfortable shifts that are supported by synchronizing motor speed for uninterrupted shifting.

Rimac assures us that the Concept_One can also be driven in one gear all the time, as it still has enough torque to smoke almost any sports car.

The Concept_One’s proprietary battery pack consists of 8,450 battery cells, each individually controlled by the Rimac Battery Management System (also developed in-house). Rimac also developed a unique liquid thermal management and low-resistance conducting system for the pack. The pack is designed to deliver 1,000 kW of power, and can absorb 400 kW during braking.

All functions of the Concept_One are controlled by a single unified computer system, which gathers information from over 500 sensors and can send telemetry data to the cloud, and thence to a smartphone or other viewer. Vehicle dynamics and powertrain functions are controlled by high-grade aluminum buttons (yes, even these are made in-house), while secondary functions are controlled through the central touchscreen.

Rimac

Rimac’s roots are in racing

“Racing affects technology like war,” says Mate Rimac. “You are encouraged to develop things quickly. You break stuff, improve and try again. It is a fast-track development process. If something works well on a racetrack, it should perform great on the road. The challenge is to bring the cost down for a non-racing application.”

“The Tesla Model S has great performance for a couple of 0-60 mph acceleration runs [but] many powertrain components face thermal challenges on the track. We want to make sure that our customers can have fun with their cars on tracks and perform well over a longer period of time. Our industrial customers often have the same requirement – the Koenigsegg Regera 9 kWh battery has to be able to deliver 500 kW of power for a long time, as the car carries basically a 1 mW power station in the form of an 8-cylinder bi-turbo combustion engine which constantly recharges the battery at high rates.”

Rimac

Lessons learned on the track are valuable not only for building supercars, but also for more mundane vehicles. “We are using our experience to incorporate many of the design features of our high-performance battery systems for applications that require affordable systems, like our nautical, bike and wheelchair projects.”

“The torque vectoring is a perfect example of a technology transfer from road cars to racing and back – we took the Concept_One torque vectoring system and adapted it for the Pikes Peak Hill Climb. There we learned so much, and improved the system on so many levels that we have implemented the racing system back into the road car.”

Speaking of racing, Rimac has also built an even more powerful car that it calls the Concept_One’s Evil Twin. The Concept_S boasts a screaming 1,384 hp and 1,800 Nm of torque. It’s 50 kg lighter than the Concept_One, and features special aerodynamic elements – a front splitter, air deflectors, side skirts and a large rear spoiler – that enhance downforce by 34 percent. The interior has been stripped of sound insulation and equipped with racing seats with four-point racing harnesses.

Battery balance

When we asked Mate Rimac what he thought about new types of battery technology such as solid-state electrolytes, silicon anodes, lithium-sulfur, etc., his answer was reminiscent of comments that Elon Musk and JB Straubel have made – so far, there’s nothing that beats Li-ion cells on all the parameters that are required in an automotive battery.

“Since I started to get involved with electric vehicles, new technologies have been announced, but not much has happened since then. Lab-level tests demonstrate good results in some aspects such as the recharge time, but a good battery needs to offer excellence in power density, energy density, cycle and calendar life, safety, operating temperatures, cost, etc. People always focus on one thing at which new promising technologies are really good at, but we can’t know their true suitability for a vehicle application until we can get our hands on them and test them. We are leveraging the best technologies available and use different chemistries and cell suppliers depending on project requirements.”

This article originally appeared in Charged Issue 26 – July/August 2016. – Subscribe now.

  • Jim Fox

    Yawn… just another Supercar, with an ICE. Just what the world doesn’t need; the best we can expect is that SOME of the technology finds a use in real-world personal transport.
    Hub motors are the future, no matter what these high-end monsters say; buses use them now, Protean has developed a bolt-on one that will convert an ICE bus to electric at feasible cost.
    Unsprung weight is a much-hyped ‘drawback’ that the average car can ignore completely and which anyway can be mitigated with new suspension design.
    All that complexity of V8 turbo ICE with its ancillary systems, plus inboard motors with driveshafts, diffs and gearboxes- they’re reinventing a ‘better’ dinosaur!!

    • dogphlap dogphlap

      What ? This article is about Rimac, they provided some tech for the Koenigsegg Regera but they don’t make hybrids with or without a plug. They make pure EVs.

      Tesla and Rimac both use inboard motors, most EV manufacturers do, that is their decision, you prefer in-wheel, you are free to buy a vehicle that employs those or maybe start your own car company. For me the Rimac solution of an inboard motor, inverter and reduction gear per driven wheel is the obvious way to go.

      In wheel motors have more going against them than just higher unsprung weight i.e. high current power cables have to go to each motor that moves with the suspension and steering so they have to be very flexible or they will break soon enough, somehow a brake has to be incorporated into each wheel and the brake creates heat which will try and cook the in-wheel motor (which also creates heat of its own). The motor is out in the worst of the weather so has to have really good sealing against water and dirt, then there is the problem of keeping the motor cool which if water cooling is chosen means two more hoses to add to the brake hose and power cables. Without an in-wheel reduction gear in-wheel motors have low starting torque so need high motor current at take off which means thicker motor cables again raising the unsprung weight. Sure it can be done, it has been done but the case for in-wheel motors is far from a no-brainer.

      • Jim Fox

        True, Rimac is to be admired for its courage but it is far from innovative- and supplying their motor[s] to a V8 supercar is no real advance. Using 4 motors, drive shafts, gearboxes et al is NOT an advance, IMO. Speaking of cooling requirements, Rimac has a great deal of problems there, since you mention it.
        The Concept_One has seven independent cooling systems and several smaller sub-systems.
        Tesla and Rimac have different objectives- Tesla being an everyday road car and Rimac a pure track vehicle. There are others making similar claims-
        TOROIDION may well outperform Rimac but my point was the world needs everyday EV’s, not these daft monsters which will sell at most a hundred or so, if that.
        http://www.bbc.com/autos/story/20150430-from-finland-the-1341-horsepower-electric-supercar
        Please do the research! HERE– PROTEAN DRIVE has solved ALL the objections you raise, and more. You surely don’t believe you know more than the engineers who’ve been developing these for a decade or more??
        https://en.wikipedia.org/wiki/BYD_K9 in China has sold thousands of EV buses ALL using hub motors and is building factories all over- including the USA.
        Low starting torque? Rubbish! The Hub motor can develop the highest torque due to the large rotor diameter, for a given magnetic field density. Thick power cables-SO WHAT- easily done with modern dielectrics.

        It will be some years before Hub Motors become mainstream, but they will, mark my words. Nissan has committed to them in the longer term, to replace ALL their EV motors. Porsche, too I believe.

        • Dalibor Gmaz

          I think you are going little off.
          1st Rimac was doing these things in 2009. His primary business is not making cars but selling tech and for that he is doing magnificent job. One of best world startups in that field.
          2nd Regera is real pinnacle of hybrid tech which really inspires all these new guys who understand that Tesla is complete rubbish under any serious load (look at Ring times or videos from Autobahn). Not everyone is looking for grandma transportation and to be honest world needs to find “passion” in otherwise really soulless EV cars.

          You need people like Rimac, like Koenigsegg to push those boundaries for people who will need inspiration to build better Zoes or Leafs. Maybe Concept One is 6 years late, indeed, but for small company out of country which is literally not existent as car manufacturer (even thou we are producing high tech parts for most prominent manufacturers), to have EV car outperform LaFerrari is marvelous achievement. Now you will get people even more eager to jump on EV bandwagon and further explore possibility.

          Leave people like Rimac to develop cars for us who live for performance and not just for vehicle to commute.

          • http://www.businessrun.si lukc1234

            I think these guys are doing awesome things, especially considering the environment in which they started and what they achieved in the short time they’ve been in the industry. So I agree with Dalibor Gmaz here.

            With technology development and new concepts being introduced, usually there are many approaches that exist and each has its benefits and drawbacks, and finally, a compromise. Just consider the reign of the ICE for the last 100 years with it’s lousy thermal efficiency, etc. But it got the job done. Now we have other options. Electric cars were contenders until about WWI, but then dropped off the map for a while.

            High-speed electric motors obviously require reduction gears and being mounted on the chassis means that the mechanical energy must be transferred to the wheels. Both these things introduce inefficiencies in the system. Although, they also provide advantages with regards to dynamic behavior of the car and wheels (which is likely noticeable only in “supercars” and not for 95% of the vehicles on the road). So it’s a game of give and take. On the other hand, there’s also new technologies, new concepts of vehicles which will be made possible by the use of in-wheel tech (in steering, in control, in complexity and servicing, in mass distribution, in braking, etc.). I think the future holds something for everyone. Not a single technology but many types and combinations, depending on your needs. I.e., in-wheel motors dominate Asian scooter market and can now be increasingly found in many vehicles. I think we can expect a lot more new stuff around EVs (with powertrains, with battery tech, with battery pack cooling, with software…) and to me, that’s exciting.

            There’s a few companies making nice headway with hub motors, like the one mentioned by Jim but also others in Europe (some actually near Croatia – http://www.in-wheel.com). I think all of these guys have been working on the tech, similarly as Tesla, for the good part of the 2000’s and have made awesome headway in the last decade or so. And they have different approaches to the powertrain architecture, so I guess we’re getting a nuanced market in a very short time. For me, that’s just more choice and freedom. Basically, I like the fact that all of us get to choose the soulfulness of our cars!

          • Jim Fox

            I repeat- admirable as their work may be it does NOTHING for Joe Average.
            You seem to be a Rimac Fanboy- which is OK but you don’t want to compare with TOROIDION, which to my mind is years ahead of Rimac.
            They have intentions of running in the next Le Mans 24 race- will Rimac be there???

          • Dalibor Gmaz

            I am little Rimac-bios. He is my homie :), but I am not against Toroidon. Quite opposite. Only thing which I find Rimac is better is that he actually sells his cars, even if its in one digit number, while Toroidon is yet to prove itself. Secondly we have test coming up on Rimac from EVO magazine and few YTers so again, slight advantage.
            In your post you answered your own question about Average Joe. If you could have 1MW EV race car doing Le Mans (my favorite race in whole wide world) then imagine if they scale down that technology down to consumer. Either by them selves or selling tech. Then you would not have overheated Tesla after 10min hard run, or 50 mile range of EV half-product.
            For me, that would be marvelous achievement because then we might have one day self driving cars doing some serious speeds and not having granny’s wagons. I feel that self driving tech might finally utilize good roads, performance of the cars which are way ahead of 30-50yr old gasoline cars, and drive you somewhere fast.
            Now imagine on top Rimac, Koenigsegg, Toroidon, and maybe Drive eO pushing those boundaries in future. Average Joe will benefit that much sooner than Tata producing some EV Nano car.

          • Jim Fox

            Look, I’m sick of your Tesla hate-filled nonsense about overheating. Without Musk, there would be NO Rimac, No Toroidion, and certainly NO Porsche/Audi?/Bmw EV’s. SO give it up- there is NO feasible dribble-down of high tech and never will be. Take your ridiculous Bugatti replacement to the track and kill yourself, do us all a favour!

          • Dalibor Gmaz

            I am not hater. Quite opposite. Critique does not mean hate. You need to be idiot to hate guy who gave us P100D. Furthermore you are not correct. There would be Rimac/Toroidion. Tesla just made investment in such projects more appealing. What is even worse you are comparing billionaire with insane government funding (and shady history with Fisker) with guy who built in 2007. FIA world record breaking converted BMW in his shack. Elons role in building Roadster or model S is CEO, not innovation like Rimac needed to be in first place. Btw. Rimac is using LiFePO4 batteries and had 92kWh for 600km range in 2011 offering 1k HP. So maybe he is not groundbreaking anymore, but he is still good mile ahead of various unproven competition (not comparing to Tesla). And he makes high quality infotainment, insane Greyp e-bikes, has partnership with Koegnigsegg, Qoros etc. All that in country sized as one US bigger city. What in hell did you did in your low 30s?!

          • Jim Fox

            “Tesla is complete rubbish under any serious load”
            “Then you would not have overheated Tesla after 10min hard run”

            These are claims without substance in support of some revhead agenda.

            No,of course you’re not a hater!!

            We think differently and I don’t want to continue a futile discussion.

          • Dalibor Gmaz

            Jim, you are really accusing me for everything wrong in the world. I am not against EV, but I am not nuthugger to Tesla or Rimac, or gasoline cars. You would not believe, but Tesla cars are not perfect. And one of biggest problem they have is overheating. I am not saying it is bad car. It is great car, but it has faults. Just like Rimac has, BMW etc.
            Did you ever look at any lap run with Tesla? No. Isnt it strange that none of major review channels did not perform any other performance test other than drag race?!
            Did you see amateur try at Ring?
            https://www.youtube.com/watch?v=YJT4OtufDss&t=0s or https://www.youtube.com/watch?v=CuPtPnK1cZY
            130+k$ car which says performance, throws 700+HP figures and then it cannot make proper lap due overheating. And Musk itself is promoting Teslas performance so yeah I would say it is obvious problem for them. Isn’t Ludicrous mode against public safety?! P100D is made just to emphasize it even more. Even if you are not 100% charged you will never see those figures they are reporting. So dont accuse Rimac for creating EV performance cars and it does not mean it will fall under hands of some “revhead” who will kill everyone on the road.
            And your WHO stats you can see that countries like Singapore have almost 3x less casualties vs US (weighted) and that is not because of EV cars. You implying that EV cars would make world safer is idiotic. Hell, you have even US people died in “autonomous” car. So think were root cause lies, and you would not believe it is not within gasoline cars.
            Toroidion still needs to produce/sell the car to prove its better than Rimac, until then Rimac has fastest EV car in production. Regardless what you think. That is the fact. And all that with few raised millions in small, automotive insignificant country. So Tesla is great, but Rimac is pushing boundaries last couple of years. Both of them will create EV “world” we will both enjoy one day.

          • Jim Fox

            nordlyst— says it better than me—

            The Rimac is interesting only to those interested in hypercars. It is
            utterly irrelevant in the bigger scheme of things. Unlike Tesla, whose
            cars are expensive without being in hypercar territory, it is no longer
            about changing perceptions and showing EVs don’t have to be dangerous,
            cramped toy cars. Tesla has already done that (in fact, it was the job
            of the Roadster, though Model S/X has made it much more widely known).

            Why
            not write about the soon to be revealed facelifted LEAF and the new ZOE
            R400 instead? With 40 kWh of useable capacity and better efficiency
            than the Bolt, and a lower price, it’s not clear at all who’s going to
            be the top dog in 2017 (tho my money would be on Nissan, if only because
            the ZOE isn’t sold everywhere – the ZOE is the better car). What is
            already clear, and quite interesting, is that BMW and VW both look
            uncompetitive despite their previously sort of impressive 50% capacity
            bump! Already the rumors are swirling that BMW will start using the
            120Ah cells (that are ready and thus could have been chosen instead of
            the 94 Ah ones) from mid-2017.

            With so much important stuff on the
            near horizon one would think you had something more relevant to write
            about than million-dollar fantasy cars.

          • Dalibor Gmaz

            And to say no feasible dribble-down of high tech is just ridiculous. Were these current cars would be if tech was not first introduced in expensive S-class, 7 series, F1, Indycar, Moto GP?! You mean VANOS/V-TEC, turbo, KERS, active aero, double clutch (available in Renault Clio!) gearboxes, adjustable suspension… how ignorant you need to be?!

  • nordlyst

    You lost me at

    > Detroit is gradually losing its position as the epicenter of the auto industry. Nowadays, news of cutting-edge developments is more likely to come from Silicon Valley, Europe or China.

    Seriously. Detroit hasn’t been the epicenter in anything but the US auto industry for many decades, if EVER. In my lifetime – and I’m 40 – Detroit has been far behind European as well as Japaese manufacturers. For the past fifteen years or so the Koreans have been ahead as well.

    There are good reasons why Detroit never got a good foothold in Europe. Some of it has to do with the fact that Europe has expensive fuel and twice as efficient a car park. Some of it has to do with different roads emphasizing different ride qualities. Some of it comes down to taste. But however you look at it, Detroit has made relatively unsophisticated products from a technical point of view. Anything from wishbones to injection, turbos or intercookers tell the same story – it is used first in Europe and eventually in America.

    I’m sorry, but to pretend Detroit has been the epicenter of the global car industry until now is totally, completely ridiculous.

  • nordlyst

    The Rimac is interesting only to those interested in hypercars. It is utterly irrelevant in the bigger scheme of things. Unlike Tesla, whose cars are expensive without being in hypercar territory, it is no longer about changing perceptions and showing EVs don’t have to be dangerous, cramped toy cars. Tesla has already done that (in fact, it was the job of the Roadster, though Model S/X has made it much more widely known).

    Why not write about the soon to be revealed facelifted LEAF and the new ZOE R400 instead? With 40 kWh of useable capacity and better efficiency than the Bolt, and a lower price, it’s not clear at all who’s going to be the top dog in 2017 (tho my money would be on Nissan, if only because the ZOE isn’t sold everywhere – the ZOE is the better car). What is already clear, and quite interesting, is that BMW and VW both look uncompetitive despite their previously sort of impressive 50% capacity bump! Already the rumors are swirling that BMW will start using the 120Ah cells (that are ready and thus could have been chosen instead of the 94 Ah ones) from mid-2017.

    With so much important stuff on the near horizon one would think you had something more relevant to write about than million-dollar fantasy cars.