Electric car kit approved ?. Yes, in Spain and Europe.

In recent years, electric cars have become more and more common, and the question,often is: which electric car to buy?.

With the new European directives, regulations to reduce CO2 emissions, the inflation of raw materials (copper, aluminum, lithium, etc.) and the problems in the supply chain, it becomes increasingly obvious that the way forward is to retrofit, that is to convert a car into electric.

The most obvious advantage is the price, and that is that converting a small city vehicle with a car conversion kit to electric can have the same or less price than buying an electric car without a license.

And without looking at the price, the fact of giving our planet earth less work and making real use of the circular economy is the most important reason.

By buying an electric car, we will have promoted the manufacture of a car from scratch, with the resulting waste of energy and resources, while converting it with a conversion kit, we will be recycling and reusing a car that would otherwise go to scrap.

Well, we are ready to offer our first “approved car kit in Spain” (and in Europe), in this case for the fabulous classic Mini. And more approved kits will follow the Mini: VW Beetle, Seat 600, Seat Ibiza, Renault Kangoo,…

The kit will be tested, approved and ready for distribution in 2023.

And what does this approved kit consist of?

The kit has a three-phase induction electric motor of 18Kw of sustained power and 35Kw of maximum power. Air-cooled and weighing about 50Kg, it will be capable of developing a maximum torque of 150Nm.

The brain of this kit will be a 108V controller with a sustained output current of about 250A, air-cooled, which makes it easier to maintain, and with a power capacity of up to 55Kw and an energy efficiency of 98%.

The batteries for the prototype will be a 10Kw lithium battery pack with its corresponding charger (the final battery pack is yet to be determined), more than enough for urban use for the Mini.

It also has a 12V dc-dc converter so that the auxiliary battery continues to power the car lights.

Also, the kit will have all the other extras such as signal wiring, high-voltage cable (so that the conversion is very simple without the need to add anything else) and a console with all the information on the Mini (led aesthetics or Mini aesthetics)

The entire drive assembly is installed on the Mini’s sub-frame, so mechanical installation is a simple step from replacing the old sub-frame with the new one from the kit. Something that the car workshops will appreciate because of how easy and fast this operation is.

How will the kit approval process be?

Well, as simple as there is nothing to do. The kit will be distributed with the approved conformity reports (including the batteries approved with the R100V2), which will suffice with the workshop certificate that assembles it to go to the Technical inspection service (MOT in the UK) and update the Mini’s technical sheet.

The Mini will be a similar vehicle, weighing exactly the same (about 650 kg), with its four seats and running on electricity, it will be possible to obtain the ZERO label without any difficulty. Of course, a silent, more fluid drive, with regenerative braking and ready to continue being driven for many more years.

The electric classic Mini is in labor.

It would be misleading if we say that this delivery has come easy, but we hope that it comes with a bread under our arms ( as we say in Spain) for the planet and especially for our cities. The new classic Mini is about to be born.

At the beginning of the pregnancy, the complications came with the aproval, where the labs insisted for each test of our prototype (in this case with the Renault Twingo) that we rest a lot, that we had to have patience, that we had to rest and let time pass. Then, after a lot of effort and expense, we managed to pass the aproval.

Then came the ITV (MOT in the UK), which had never seen a delivery like this, and they began to panic about the unknown, so not to assist us in the delivery, they used excuses such as, the documentation is not printed in the colour of ink that we are used to, and similar… but after much more effort, we managed to reach an agreement and use the ink and the type of paper that was required (They would not understand this sarcasm either).

Later, more complications came in the following weeks of pregnancy with the batteries, where the European Union long ago released a new R100 regulation, to warn us that batteries could no longer be installed without new R100 approval in electric vehicles throughout Europe. And all the manufacturers in the EU, queuing to approve their batteries, so once again we needed to be patient, they can’t serve everyone. The collapsed primary health of unapproved batteries. But we finally got approved batteries.

Well, the delivery is about to arrive, and with everything we need, we are ready to give birth to a beautiful classic Mini powered by an electric motor.

As we have been doing in recent times, we continue to group ourselves by car models that we want to convert to electric. The Mini is the largest group, with 112 interested at the time of publishing this article. So we begin.

We are in the design phase, so the requirments are still up for grabs, but it will surely have a 90V system, with an electric motor of around 25Kw, a battery pack of around 20Kw and with all the essence of the Mini, ready to go with a zero emissions sticker.

Technicall aspects will still change, but in general it will be like described.

And when will it cost? Well, let’s hope it’s the most affordable for lovers of the classic Mini, and let’s also hope that by the time the kit is approved and available, the government has taken out more aid for the conversion of vehicles to electric than what has already been published. Let’s see if it is possible for them to help with €7,000, just as they do with new electric vehicles, with the difference that our converted and recycled vehicles have used much less energy to give birth.

And when will it be ready? Well, we estimated a quick delivery but with great pain. Between 3 and 6 months for the prototype to be designed and working, plus another 3 to 6 months to aprove the kit. With what, we hope that within no more than a year the kits will be available to enjoy, or throughout Spain or throughout Europe.

Telemetry confirmed good news.

We went to the speed track, in Cartagena, where we could use the track for some time. We thank you very much for their help.



We decided to drive a non-stopping run at a constant current, to see how other aspects of the prototype (our electric Twingo), as range, temperatures, rpms..etc. . were affected.


Due to the amount of corners the track had, we couldn’t get a stable current consumption, but at least we could monitor it, and that was the result for 20 min drive.



We can see an average of 120 Amp out of the battery pack most of the time. And also, around 210 Amp out of the controller.


All this time we have consume around 3,3 Kw, which is a stoning 46% of the total capacity.



But, ¿how this test affected to the rest of the components?. Well, we could see the controller a bit too hot, so that led us to think about an additional cool system for the controller. We saw a peak of 72ºC, which is the limit of a healthy temperature, so we are working in some system to dissipate faster the temperature of the heat sink controller.



The motor also was a bit warm, but we could see a very healthy average between 40ºC and 50ºC, so no drama about it, for now.



We can also see that we tried to get the motor at the stable revolution rate of 2500 rpm, which is the manufacturer  recommended rpm rate to get the maximum torque. Seeing that we did drive a maximum rpm efficiency it is also good news. So, Telemetry came ok at Cartagena´s speed track.




So, a little video with a summary of the whole test can be enjoyed here. If you need a professional video recording work for your project, please contact:


Testing, testing, .. out road.

60_testingThe conversion of a petrol or diesel vehicle is the most sustainable and economical way of driving a perfect electric car. The main idea behind this, is to re-use all the vehicle´s components that have no impact in the internal combustion engine, and to substitute it with a full electric motor. Engine, radiator, petrol tank, exhaust tubes, alternator, etc will be removed, reducing the car´s weight. By having a chassis with all the necessary parts for driving, as interior, brakes, tyres, shock absorbers, etc, all effort is reduced to install and design an electric system with a motor and batteries.

61_testingIt is very important to choose a good design for the electric system, electric motor, battery pack and motor controller should have the same specifications in power and speed to the ones the car when it was originally designed. Too much power could damage the traction components or may not respond as well to breaking, and too little could cause the gears no to acquire the adequate speed.

Elektrun is a project that was born two years ago to probe the concept of transforming a city car to electric, ideal for short trips within the city.  We have chosen a Renault Twingo to build a prototype,  it is a vehicle with little weight and a reduced size, and after two years of design, test and experiments we have made it work.

62_testingThe main issue for this kind of transformation is the range the batteries will achieve. Now days there are cars that can drive 700kms in one single charge, in order to achieve that, it needs at least between 70Kw and 80Kw. Our prototype comes with a 7,4Kw.



63_testingThis prototype has an 15KW AC induction motor with a maximum torque of 80Nm, a battery pack of 72V and 100Ah, it has an 80V and 350Amp controller. This can speed the car to 90km/h in 5th gear.

The first tests shown the total weight didn’t affect at all in corners, the shock absorbers responded well as expected, and by removing the engine noise the driving was much more comfortable.

64_testingAn additional vacuum pump was installed to help the braking system. The braking was also performing very well as, it responded to hard braking and kept the car stopped in steep ramps.


65_testingA small display was installed in the interior to monitor, at any time, battery usage, current, motor temperature, state of charge, etc.


66_testingLights and interior accessories as electric windows, radio, air flow, window cleaner, etc were kept in the car.

This car takes 8 hours to fully charge the battery pack, although there are chargers that could reduce this time from 6 to 4 hours.



You can see a video about the first tests here:

Batteries, The big deal.

The batteries world is in constant change nowadays with the electric vehicles take off , the new and improved power storage, super capacitors, and the new kid on the block, graphene.

Lead batteries and AGM or gel are a thing of the past. We are now having the Li-ion present going to the new Li-air future.

The necessity of longer trips, fast charging times a better performance are a must in electric vehicles, and more and more, those demands are the big deal in EV.

Fresh air, still to come.

Till now, the obvious technology in the batteries department has been lithium-ion. But since some time ago, a new technology based in air is the real interest for manufacturers and EV developers. The new Li-air promises up to 10 times the energy density of their cousins li-ion. IBM´s project 500 has the aim of driving 500 miles in one single charge  in a family car using those new batteries. Although this has been achieved already by the Metron Institute (Slovenia) with LiFePo4 technology.

Li-air cells

The way it works is, a Li-air cell uses cheap carbon as a cathode (instead of cobalt), a molecule of a oxygen pivots through the cathode and gives the battery its name. But it has remained theoretical because of its big challenges. Among them: the other electrode in such batteries—the anode—is pure lithium metal, which provides a lot of energy but also ignites when exposed to water, carbon dioxide, or other contaminants.

Such is the challenge, that IBM and JCESR (Joint Center for Energy Storage Research) have decided to step back from the LI-air project, and IBM has turned his favour to a Lithium Sodium technology.

Li-Na cells

But with all these changes, a new development continues, and metal chemistries are also under development, in particular Aluminium-Air. An Israeli company (Phinergy), has claimed to solved corrosion, and recharging issues with a silver based catalyst. A prototype EV claimed to have 1600km range with Al-air batteries. However those cells cannot be electrically re-charged having to re-load them mechanically and topped up with water.

It smells sulphur.

Lithium Sulphur cells are another energy dense technology that could solve the needs for the EV in a near future. This new chemistry tends to solve issues like life cycle and stability. Based around a carbon based electrode, those cells are said they could go ahead Li-air technology.

Li-S cells

Many studies and research from Imperial College (London)  to German company BASF are putting their efforts into Li-S. They said this could be the 4th generation of batteries, expecting ranges of 400Kms in the next decade. Scientists at Lawrence Berkeley Labs (California) have introduced graphene oxide into Li-S cells that are said to deliver 1,500 charge cycles without deterioration.

Other researchers from ETH Zurich are working with Sodium-ion cells, stating that are much cheaper than Li-ion. But they have two major problems; they are three times heavier than lithium and tend to lose capacity when not in use.

Lithium Ion are here to stay.

Despite all the development in the power storage field, one thing is clear, most of EV at the moment go for Li-ion, and the fact that manufacturer are offering cheaper prices and even Tesla is building a new Lithium batteries plant, makes you think that in the long term this technology is here to stay.

Li-ion cells

Li-Ion developers, Bosch, GS Yuasa and Mitsubishi, claim that the could reduce the prices to half in the Li-ion filed, and double the capacity, that would make EV much more approachable to normal consumers.

There are also many new promising developments with carbon, but the gap between the lab and the factories is too big to stop producing Li-ion for EVs.

graphene cells

The magazine “Electric & Hybrid Vehicle Technology International” writes in their July 2014 issue about the carbon:

“The real deal?. A new type of dual-carbon battery technology that could potentially be a game changer for EVs has been launched by a Japanese R&D company. Called Ryden, the new battery is said to offer energy density that’s comparable to Li-ion products, but over a much longer functional lifetime with far improved safety and cradle-tocradle sustainability, says Power Japan Plus, which will begin production of the cells later this year at its manufacturing facility in Okinawa, Japan. The Ryden battery makes use of a completely unique chemistry, with both the anode and the cathode made of carbon. “Power Japan Plus is a materials engineer for a new class of carbon material that balances economics, performance and sustainability in a world of constrained resources,” says CEO Dou Kani. “The Ryden dual-carbon battery is the energy storage breakthrough needed to bring green technology such as electric vehicles to mass market.” Kani says that the Ryden battery balances a breadth of consumer demands previously unattainable by a single battery chemistry. In terms of performance, the new battery is not only energy dense and operates at above four volts, but also offers a charge time that’s 20 times faster than that of current Li-ion designs.

dual carbon cellsThe Ryden technology has been created so that it can slot directly into existing manufacturing processes, requiring no change to existing manufacturing lines. Furthermore, the battery enables consolidation of the supply chain, with carbon being the only active material used. As a result, manufacture of the Ryden battery is under no threat of supply disruption or price spikes from rare earth materials, rare metals or heavy metals. According to Power Japan Plus, its technology is the first high-performance battery that meets consumer cycle-life demands, being rated for more than 3,000 charge/discharge cycles. The breakthrough also eliminates the unstable active material used in other high-performance batteries, thus greatly reducing fire and explosion hazard. Furthermore, the new battery experiences minimal thermal change during operation, eliminating the threat of a thermal runaway. Finally, it can be 100% charged and discharged with no damage. Adding to the sense that the Ryden battery could be a key moment for EVs is that it is 100% recyclable, vastly improving the cradle-to-cradle sustainability of battery technology. As an add-on to this, Power Japan Plus is testing the battery with its organic carbon complex material, working toward the goal of producing the battery with all-organic carbon in the future. Made of naturally grown organic cotton, the carbon complex exhibits properties not seen in other carbon materials. By controlling the size of the carbon crystals during production, Power Japan Plus can engineer the carbon complex for a variety of applications.”

How to convert your car to electric?

quien mato el coche electricoWhen I had the idea of converting my own car to electric, I had two goals in mind. To be able to drive a novel car, that wouldn´t make any noise and the cost for the fuel be little or nothing.  The other goal was to stop once for all contributing to dirt our environment and be able to tell the rest of the people “Yes, we can”, now days you also can have an electric vehicle exactly as it was at the beginning of the 20th century in New York (See the documentary “Who killed the electric car?” ).

Little by little, this idea was more and more real, asking other people, researching on the net and other countries where this was already a reality, I started the project of building an electric car.

Choosing a donor car.

The first step, once everything is clear, was to choose a cheap car and appropriate for the project The best cars are old vehicles o classic cars. The reason for this is because they are not complex in their design and electronics are not playing an important role in the car functions.  There is no need to be afraid at this point, nothing anyone can overcome reading a bit about the chosen car.

01_renault_twingo_elelectricAnother important requirement is the car to be light in weight, less than 1000 Kg is more than adequate, and 800Kg is ideal.  The reason behind this is the resistance the car has because of the friction in the roads, the more resistance, the more electric energy it will need to drive.

There is also other elements that a high speed affects the performance as the Aerodynamic coefficient, but this will leave it for the time being.

The old Renault Twingo is a car that weights very little, it doesn’t depends much on electronics (it doesn’t come with power steering or automatic gearbox). So I decided to get a cheap second hand Twingo and I spent 500€.



And now, the motor.

The motor is something you need to spend some time researching on it to take the correct decision. By choosing a small car, the motor doesn’t have to be very powerful, so a 7 to 15 Kw motor can be just perfect. There are two kinds of motors:  DC motors (direct current) and AC motors (alternating current). The first ones are cheaper, more accessible in second hand markets or scrap yards, but they are less efficient. The second ones are more expensive; they weigh less and are more efficient. Then according to other technical aspects are synchronous motor and asynchronous, also other with permanent magnets, which supposed to be top of the list. As examples, there are 7 Kw motors from China that cost less that 1000€, while in Europe or USA you can have 15 to 25Kw motor between 2000 and 4000€. I decided to go for an Slovenian 14 Kw motor, branded Letrika. I knew this provider at the electric car fair EVS27 in 2013.

Motor electrico

Motor electrico

Lets go to the motor controller.

This is one of the main components, it is also one of the most expensive and it goes paired with the motor for two reasons: One, it is the one in charge to convert the batteries electric power to the correct voltage necessary for the motor, and the second, to regulate the speed of the motor, so the controller needs to be designed for it. As with the motor, there are DC controllers and AC controllers. The good news is that most of the motor manufacturer they also do the controllers, and if the don’t, normally the motor can be configured for generic configurable controllers.

Controllers are also classified according to the maximum current they can feed, the more current and voltage, the more powerful l the motor will be. There are several brands as Brusa, Curtis, Sagem, ..


03_curtis_controllerI got a Curtis controller, medium range for AC motor, the Curtis controller 1236. Most of the controllers are programmable, so you can adapt it to your own motor. You will have to study a bit about variety and features of the controller best suits you.



And we get to the batteries, the queens.

Batteries are the most important element in a electric vehicle, as they will define how much power and how much range the electric car will have. I hope one day this element will be the less important, but for the time being, this technology is more complex than we may think. The appropriate batteries bank is conditioned by the maximum distance the car will drive in one single char and also the charger and the BMS (Battery Management  System).  Not all kind of batteries can be charged or discharged in the same way, if you don’t follow the manufacturer requirements and limits, batteries can be affected and their life span be reduced.

There are several technologies in the market right now, but in practical terms we can talk about 3 or 4 types. Lets start by the cheap ones.

04_lead_batteryLead Batteries. They are the cheapest ones, but the least suitable  ones because its design, as they are not design to provide a constant current all the time, but to provide a very strong one in one go, and this is not what a controller for a electric motor needs. The good news for a budget car, is that even dead, you can re-acconditionate them or de-sulphate them. This is a delicate process as the content inside the batteries is sulphuric acid, so if you are a bit un-sure of what you are doing, better not to try. I have done it being very careful, and following all the security precautions and using protecting gloves, glasses and mask (in an open environment), at the end you need to neutralize the acid with sodium bicarbonate before wasting it to the sink. You can also buy them to avoid all this hassle. They are very heavy, but can be charged with any standard charger.


05_72V_agm_batteriesAGM or gel batteries.  Those are deep cycle batteries, they are lead batteries with more efficient electrolyte gel. They are a bit more expensive but they are designed for electric cars. They are very heavy too, and there are manufacturer that assure up to 1000 cycles before losing charge capacity. The charger has to be specially design for gel batteries to follow a correct charge parameters for gel or AGM. They are not very expensive, I bought 6 of them, 12V at 100Ah for about 900€.


06_lithium_battery Lithium batteries. This already more expensive, but they weight about half and they have double capacity. Those are the standard option for electric cars. They use to come in 3.7 cells, so you have to get many of them to achieve the desire voltage. Another VERY IMPORTANT issue is that lithium batteries need to be managed (charged and discharged) by a BMS (Battery Management System). The reason is that these batteries cannot be charged or discharged outside the recommended limits by the manufacturer. As an example, 18650 lithium cells can only be charged at a maximum of 4.1V and discharged at a minimum of 2.5V.
–    Pyrophosphate batteries (LiFePO4). They are the most expensive of all but also they have the more energy capacity.


Enough batteries for now..


07_dc_dc_converter_72vAnother very important component is a current converter for high voltage to 12V.
When we remove the IC engine (Internal combustion), one of the components that also disappears is the alternator, the one in charge of keep the battery always at the proper voltage (in this case we could call it the auxiliary battery) for lights, electric windows, radio, etc. So, as the alternator is missing, we need a system have it always charged, for example, a DC converter  72V to 12V.




Well, that´s it, isn’t ?. No, still something important, the brakes.

For the brakes, you need to supply the vacuum that the IC engine use to make for the brake booster. So we need to install a vacuum pump in order to replace the missing one in the IC engine.


Then you need other small components, but equally important as a pedal accelerator, a contactor, some relays, fuses, etc.


Those small components are as relevant as the big ones, because even with the motor and controller, with no cables, there is no use. Also, you need to see the high voltage requirements that the motor manufacturer recommends. Also the signal cables are also important in following no just the diameter but the isolation.

Now the adventure starts… just install everything in the car.



If you are interested in converting your car to electric and need more information, support, documentation or just someone who share your hobby, you can contact with us by clicking here.