Range extender !

I did share this idea within another post, but either it got lost within the other topics or other forum members do not consider it as pertinent.

In short, the biggest drawback of electric cars is their range and the time necessary to recharge the battery.

Thus the idea one can read in several forums about hooking a generator placed in a trailer

My thougt goes along that line but not to be placed in a trailor but on the roof in one of these aerodynamic boxes.

The idea would be to only have a few liters of fuel to run a generator, one day a turbine and hook it directly to the batteries the same way those battery uogrades are done by the website called i think enginner.us.

If such units where availabke, i woul certainly rent them for the cases i need to make very long trips. It would be much cheaper that loading the car on a truck, one could even imagine car rentals renting them with a similar system of conveying them from one town to the other in other to match demand.

Obviously it is too early to even expect a standard high voltage DC plug, but I thought of sharing the idea maybe some people grab it to make a prototype, then it might go further, as it is outside my expertise.

Looking forward to your thoughts.

Charging is a problem. J1772 prevents you from charging while driving.

The other problem is our builtin charger. It wont charge with less than 8 amperes.

So we would have to find a place in DC land where to plug in. We would have to talk canbus to the battery management unit. We might end up with something as complicated as CHAdeMO and add a gas burning engine and tank and all that above our head.

Have a look at third world flea markets and try finding a used RTG

http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator

They fit nicely on our roof and get good cooling while driving. :lol:

This might be a nice gadget for April 1st. A fake one of coarse. I would not like a real RTG close to me.


I have been thinking about adding another battery pack in the trunk. Again, how do I tell the turtle that she has got two batteries now to take care off. First step will be canbus hacking. I have unpacked my arduino yesterday and I am trying to get hold of a machina (ardunio with canbus) because ELM and OBD-2 will not be fast enough to watch what is going on.

Please feel not offended. Some ICE on the roof looks tempting at first sight but it is not that easy. Some ICE in a trailer pushing the i-MiEV might make the turtle thinking she is driving downhill and work without a lot of trouble.

Hi Peter,

The RTG would definitely be unrealistic . I see your reserves for an ICE on the roof but somewhere in the back of my head I was thinking of a small turbine. There is a company in california (I do not remember their name) which actually was started for applications of turbines in cars then went to energy production and I think has made a powerfull prototype with full electric propulsion but instead of hudreds of kilos of batteries like in the Tesla, they have opted for the turbine to extend the range. The performance is stellar and fuel economy is similar to a Polo.

Now if one day such small turbine could fit, only for special occasions outside the living space of the EVs, I think we might actually get ride of range anxiety...

Thanks

Llecentaur said:

Looking forward to your thoughts.

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The car is very well engineered for what it was designed to do - A mostly urban commuter car with a 60 to 80 mile range. If that suits your needs, then buying an iMiEV is an excellent choice, IMO

If you need to go farther or faster, you should look into buying a car which has those capabilities, rather than trying to redesign something that was never intended for such use - A Chevy Volt sounds like the perfect car for what you want to do . . . . or maybe a plug in Prius

The iMiEV requires about 20 amps from it's battery to do a steady 40 mph on level ground - Faster would require even more. You need about twice that (40 amps) to maintain 55 or 60 MPH. 20 amps from a 330 volt battery is 6600 watts, so your 'roof generator' would need to be a 10 to 12 HP unit capable of at least 7500 watts and those all weigh lots more than the roof could support . . . . and they wouldn't fit in your luggage carrier anyway. Any attempt to connect something directly to the batteries would void any warranty and it would also be dangerous. The little 3300 watt charger built into the car has many computerized protections for the battery pack built into it and one of those is to make sure you cannot drive the car while you are charging it - Charging the car in any other manner would be ill advised

My thoughts are . . . . you're looking at the wrong car

Don

Hi Don,

Thank you for those power requirement information. I understand that to provide 5000 to 7000 watts the equipment would be much too heavy, I had in mind more like 2000 W but clearly that is well below the requirements.

Thank you for the feedback.

When Karin and me decided now is the time, our thinking was in 5 years double as much battery for half the price.

Today we read no longer science fiction, silicon is going to replace carbon. Batteries 5 times the capacity have been shown in prototypes, lasting only 30 recharge cycles but promissing. It is realistic to think we can replace our LiPo with something silicon giving us a range of 750 kilometers in a few years only and a range of 2500 kilometers in 10 years.

How about range anxiety? Those poor gas guzzlers are going to fill up their cars about twice per week and we are going to charge only once per month.

In Germany we are facing 35 cents per kilowatt hour and rising. Your own solar panels on your own roof are already cheaper. With our main fuse of 35 amperes those batteries will be the end of the grid. People will either drive to the power plant and get their electricity for 1/3 of the price or they'll make their own power. What looks funny right now gets more serious when you look at petrol prices.

I am running around my county convincing people we need open power sockets. I have seen it is almost impossible to plant an electric socket near a place selling gas. Security regulations. I have had a look under the hood of a Chevy Volt with gas and electricity side by side :shock:

I am sure the i-MiEV is the right choice for most of us. Sometimes needing more range I still think hybrids are a bad choice. I can feel the need sometimes to show we can go everywhere in an electric car - that hits me too and I am willing to do funny things including putting an RTG made of styro foam on the roof :mrgreen:

Hi Peter,

I hope your numbers come through. My aim was to replace the original batteries in 5 to 7 years (5 year warranty on Citroen czero) with about 3000 USD batteries that would have same longevity and 3 times the capacity.

Do you think it would be a matter of drop in the new batteries assuming same size and voltage just a higher capacity or will we have to reprogram or buy a new battery management system ?

We still have time but there should be a thread exclusively for this purpose.

From what I have seen our batteries, lithium iron are the cheapest and most reliable compared to lithium cobalt, the most explosive and most expensive as used in Fisker and Tesla. The lithium manganese are somewhat in the middle. All of these are very much different in charge algorithm and voltage. So we need to replace the battery pack and reprogramme the battery management unit.

If that is not done by Mitsu we still can replace batteries, charger and BMU with something different and most likely at a reasonable price. That is how conversions are done, except the i-MiEV is already electric so very little work is necessary. The i-MiEV has the potential to become a cult car like the Citroen 2CV. I am sure there will come conversion kits as soon as those new batteries arrive.

Llecentaur said:

Do you think it would be a matter of drop in the new batteries assuming same size and voltage just a higher capacity or will we have to reprogram or buy a new battery management system ?

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You'd need to nearly completely redesign the car, I'm afraid. I doubt we'll ever see any conversion kits for it either . . . . they just didn't sell enough of these to justify the necessary engineering. They sold literally millions of 2CV's but maybe only a thousand or two iMiEV's

Your new battery bank will need to have a new BMS system designed specifically for the battery chemistry and capacity matching your new pack - I'm guessing the BMS alone would run you $1500 to $2k US and then it still wouldn't work with the cars onboard diagnostic systems. Programming the new generic BMS into the cars electronics will be very difficult, if not impossible . . . . well, I guess nothing is impossible - Suffice it to say it would be very difficult

Our current battery pack capacity is 50 AH and we recharge that with a built in 10 amp charger. If your capacity was tripled to say 150 AH, your stock charger would take about 20 hours to do a recharge, so you'd probably want another charger . . . . something on the order of 25 or 30 amps I would guess. The charger alone would probably run you $3500

Assuming your new triple capacity batteries could be had for *only* $5K US, then you'd still have to somehow get them installed in the stainless package which bolts to the underside of the car . . . . or build a brand new one from scratch - You would easily have $10K US or more in this project . . . . and even then, it probably wouldn't be trouble-proof

One day, someone with lots of technical expertise will no doubt do a one off modification of one of our cars with something like you propose, but it will likely take them months and $10K or more to do - I really doubt you'll ever see any 'bolt on' modification packages for sale to DIY'ers to do this themselves. The engineering costs would be prohibitive and the package would be so costly they'd have few if any customers

I *hope* that 7 or 8 years from now when my car needs a new battery pack, I can buy something reasonably priced from Mitsu to replace the OEM pack . . . . or maybe they'll be able to just refurbish my current battery so I can get a few more years of use from it - If a new pack has about the same range and I can replace it for only $5K or so, I'd probably be interested . . . . wishing or hoping for any great advancement in battery technology to be able to bolt into an old car probably isn't going to happen . . . . at any price. I suspect for most of us, when the OEM battery is done, we'll just move on to another car

We bought the car understanding very well all of it's limitations. We knew we wouldn't be taking any long trips in it, but then we rarely have the need to go much farther than 50 miles or so in a single day. It works very well for us because of that. If we needed to go farther or if we could only have just one car, we would have bought something else

Don

Hi Don,

Well I hope we will have some choices...

Are you sure about the number of sales, i am quite sure to have read that the imiev sales would have been around 20'000 or so not a few thousand. Most of them in Japan and south east asia.

I am not an expert, so please correct me if My assumption is inaccurate:

Each battery has a type, voltage and capacity. I understand that the BMS controls the charge state through the voltage of the cell and will charge until a certain voltage will be achieved. now, if in 5 years, we have a battery of the same type with same or smaller size which has the exact same voltage but double the capacity, why would our BMS not be able to charge it up to its max voltage, simply he will need twice the time given same charger is used?

Then if Nowdays, I charge for an average of 8 hours (220V) for my daily driving needs, then why, as long as the average say weekly usage is within the same bracket, the user would not be able to use the same charger, he would just be charging during the night and drive off without a fully charged battery which would even partially charged have a higher range than our present batteries.

You see i am assuming that the average usage would be roughly the same, just marginally higher, but the car/battery combination would be able to comply with some of those heavy days where we would exceed the average battery's range/charge capacity (assuming no fast charging station is used durin the trip.)

Thanks

Llecentaur said:

Then if Nowdays, I charge for an average of 8 hours (220V) for my daily driving needs, then why, as long as the average say weekly usage is within the same bracket, the user would not be able to use the same charger, he would just be charging during the night and drive off without a fully charged battery which would even partially charged have a higher range than our present batteries.

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Under this scenario, you would actually have more range than a full charge now because the charger wouldn't ramp down and sit idle for an hour or so before being unplugged. It would keep charging at full speed until you unplug it (or precondition the car). And if you needed even more range, just keep the car plugged in longer and start charging up the other half of the battery. Every hour of charge time at the car's full level 2 would give you 10-13 miles of range. So, after 8 hours of charging, you could have 80-104 miles of range, 100-130 miles after 10 hours of charging (not accounting for charger timeouts and other real-world factors, based on continuous 3.3 kW, energy economy between 3 and 4 miles/kWh).

2X capacity batteries may not be that far off. Even 1.5X capacity batteries can be done in 2-4 years and maintain the same size. Look at NiMH progression over the last few years. Before, the largest AA only held ~1900 mAh, now hold 2,800 mAh. Even laptop batteries over the last 3 years have increased capacity by about 40%. My laptop has an 86 Wh battery in it, made 3 years ago. A week ago, I come across a battery in a similar laptop, smaller, but held 97 Wh.

Don said:

You'd need to nearly completely redesign the car, I'm afraid. I doubt we'll ever see any conversion kits for it either . . . . they just didn't sell enough of these to justify the necessary engineering. They sold literally millions of 2CV's but maybe only a thousand or two iMiEV's

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I think Don's analysis is a bit too pessimistic. For one thing, InsideEV's claimed about 6 months ago that 29,000 i-MiEV's and their Citroen and Peugeot cousins had been manufactured. That's almost twice as many i-MiEV's as original Honda Insights whose intermodule communications have been reverse-engineered sufficiently to allow a talented owner to replace the Insight's NiMH battery pack with a Li ion battery pack. He has designed a BMS that anyone with circuit board building skills could build. He has been running Li ion battery packs in a couple of Insights for 2 or 3 years with no drama. He has now replaced the NiMH battery pack in a Civic Hybrid with an Li ion battery pack along with his custom BMS.

Several talented i-MiEV owners are making progress decoding the i-MiEV's CAN bus protocols, so I would think that by the time a more advanced battery cells are available, i-MiEV owners should have the option of replacing their out-of-warranty OEM battery packs for a relatively reasonable price.

Don is a realist and we do need somebody around to keep our feet on the floor or we'll start to convert airplanes to electric drive.

My worst case scenario is, Mitsu will do nothing and we are on our own. We have got a car, a drivetrain with 3 phase engine and a vehicle control unit.

The vehicle control unit will take care of almost everything but we need to spoof the battery management unit. A machina or arduino with canbus will take care of that. all we have to do get the batteries installed take care of them and get a new charger.

Many conversions are done with most of them a few cars only. So our i-MiEV will be one of the easiest to do.

My preferred one is Mitsu will do all the work, reprogramme battery management unit and charger as they had already to do to build in smaller batteries of different chemistry.

I also tend to think that Mitsu rather than Citroen or Peugeot will make that transition effort. At least that would make sense in the concept that the imiev was and shoukd remain a shiw case of Mitsu's know how.

Lets imagine how much money they have invested in this project versus hiw much is needed to make those updates to show the public that these 5-10 year old imievs where a good choice in 2011 and are still competitive in say 2017. That would then be the time when the iMiev coukd become the cult car we some of us are anticipating.

Regarding CANBus protocol and data collection, I am not qualified to help directly but do have two excellent IT employees whi could very effectively program iphone or android monitoring tools. My comoany is not in a position to ofer their work but I can make them availabke at cost if that is of any help and will participate in any setup. But we need an engineer to run the project, users to run tests, then those mobile APPs coukd be handy.

By the way I did buy a BT ODBII reader that I connect to my Galaxy note to read my Audi's engine data. I guess this is the same norm to connect to the iMiev ?

I'm not at all pessimistic about new battery development - I think every year we'll be reading about new EV's with smaller, higher density, more efficient battery technology which will enable a small-ish EV to go farther and farther . . . . I certainly believe that's coming

What I am a bit pessimistic about is any of that new technology being reverse adaptable to older gen1 and gen 2 EV's like we're all driving. There would be even more EV's on the road now, but the battery technology is what's holding things up and when the new battery technology comes along, they'll be designing new EV's around it and building as many of those as the battery supply will allow . . . . few will be working on a way to adapt the newer technology to installation in older cars

Our battery pack is contained in a very odd shaped metal protective shell which bolts to the underside of the car - They fit the cells into an unusual shape to take advantage of the raised portion of the floor under the seats. I think it's not very likely that the new cells will be the exact same size and shape as the older cells, which means fitting the new ones in the already existing 'container' will be next to impossible - The newer, higher density cells may require different spacing for cooling purposes, etc. The odds that someone will be selling a bolt-in kit for an iMiEV even if it turns out they sell 500,000 of these cars just isn't very great, IMO

Hope I'm wrong and one day we'll have affordable alternatives which will turn our 75 mile cars into 150 mile cars at much less than the cost of buying a newer EV . . . . because I really like this car and would enjoy driving it forever - "What's that weird old car Grandpa is driving? Oh, it an old 2012 something or other!"

Don

Well, we have about five years to prepare for battery replacement/upgrade, and I also hope that Mitsubishi will provide a path.

In the meantime, a range-extending battery concept that Enginer (now defunct?) was implementing seemed quite simple: a 48v pack with a dc-dc converter, with the output of that converter being injected directly into the EV or Hybrid's battery pack. The add-on 48v pack could be any chemistry, with its own self-contained charger and BMS, the BMS also protecting that add-on pack from over-discharge.

Trick would be to ensure the dc-dc output voltage is very carefully regulated and well below the iMiEV's pack upper limit (to allow the existing iMiEV BMS to stay fully functional). As a first cut I'd be inclined to set that voltage somewhere around the iMiEV's 30%SOC voltage.

I was surprised that third-party add-on packs to conventional hybrids don't bother interacting with the existing vehicle BMS, but simply provide another current source, just as the output of a regenerating motor does - recognizing that the motor output is indeed managed to avoid overheating or overcharging an already charged battery.

Hmmm, since I already have a whole bunch of Headway 12AHr cells which I use for both my electric scooter (24v) and electric outboard (48v) with an excellent model-airplane LiFePO4 BMS managing each cell individually, I should get ambitious and prove this concept on one of my other EVs… anyone have any suggestions for a 48v-->330v(adjustable) dc-dc converter whose output stage must be protected to avoid the battery voltage from zapping it (simple diode isolation?)?

Feeding something parallel to the heater e.g. should be possible. That will turn our heater into a regenerative heater.

There is no voltage related to our state of charge. Start feeding at soc 50% on the gauge and keep looking at the gauge, stop when the gauge shows 75%. Feed some 340 volts but limit current to 10A or 20A. That will most likely turn our power meter towards blue. It will reduce power drawn from the batteries but feed little if any into the batteries.

JoeS said:

In the meantime, a range-extending battery concept that Enginer (now defunct?) was implementing seemed quite simple: a 48v pack with a dc-dc converter, with the output of that converter being injected directly into the EV or Hybrid's battery pack. )?

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You called it Joe- Enginer is out of business, though their website is still up. :twisted: I checked with a friend and now-former Enginer dealer. Here's a snippett that's civil...
"Oh, very dead. I wouldn't be surprised if he's still taking money."

I have touched on this subject somewhere else in the forum. I was thinking to tie into the HV feed of the car's DC-DC converter. Maybe also put some flexible solar on the roof of the car to feed the secondary battery pack if it would be worthwhile.

PV1 said:

I was thinking to tie into the HV feed of the car's DC-DC converter. Maybe also put some flexible solar on the roof of the car to feed the secondary battery pack if it would be worthwhile.

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The location that one ties into the car's HVDC bus (charger out, dc-dc input, main pack connector) shouldn't matter as long as the cable and fuse is matched for ampacity and the effect on any bypassed instrumentation is understood.
I'm a fan of solar, but view it as only a hood ornament on daily drivers. The yield compared to cost, along with the added weight and aero challenges make it difficult to justify for any reason other than "I Wanted It!".