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Discussion Starter #1
There always seems to be lots of new stories about exciting new battery technology. But just like media attention regarding 'cures' for cancer, they are as much about PR and gaining investment rather than something just round the corner.

Lead acid batteries have been the primary means of industrial motive power for over a century...but the improvements over that time were incremental.

Lithium ion is now the pinnacle for CURRENT domestic EVs....so what is all this talk of doubling the range in a few years? There are physical limitations. Yes, the Tesla gets huge range by modern standards, but that's because it's a huge vehicle with a huge battery.

So when people say that in 3 years our current EVs will be out dated, I don't buy it. Will our current ev ranges of 30 to 90 miles be doubled or tripled in a few years for the same battery size and cost? I doubt it.

I'd welcome the views however of more informed individuals.
 
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I read something about being able to refill your battery with charged electrolytes in a couple of years. I've no idea if that's even possible, but it sounded brilliant... (If a bit dangerous?)
 

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Discussion Starter #3
I read something about being able to refill your battery with charged electrolytes in a couple of years. I've no idea if that's even possible, but it sounded brilliant... (If a bit dangerous?)
Errrr...I think not! Access, safety, storage etc.
 

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There can easily be a relatively small increase in battery capacity of current technology batteries. Improvements in quality and cell packaging are allowing greater energy denisity, but with increased density, also comes the issues of increased failure rates. What works on a starionary laptop battery may not work in an EV cell subject to constant vibration and shocks. Thats not a problem for TESLA etc where individual cells can be replaced, but in vehicles that use packs like the A123, one duff cell = a replacement pack. With a lot of vehicles now using relatively high voltage you have a pack with 100 + (Could be 200 could be 500) cells . WIth the increase in cell numbers comes increased probability of cell failure. So adding smaller packaged cells to increase the number used hence the range, also carries additional risks.
I recently looked at some used ZEBRA packs, great energy density and high voltage , but all had at least one failed cell. WIth a ZEBRA, the case is actually welded and fully sealed, repair is not an option. Perhaps thats why ZEBRA battery packs are not in favor anymore.
The question is what range do people need, most people on this forum probably do less than 40miles per day, perhaps the time is here to revist the way we use our cars. Own and EV, hire an ICE vehicle when you need it. Work with people in the locality, own and EV and share and ICE between you.
Too many people are expecting EVs to be a replacement for their ICE vehicle,but storing 40 to 50KWh in a hatchback is challenging. Also pointless for most days usage, and carrying a huge pack about would mean a higher energy consumption for most of the users journeys.
Its all about compromise, we own a number of vehicles, I work on EVs for a living, I have them available so we can use two EVs for most of our daily journeys, but we also have a diesel vehicle about for longer journeys, parts collection etc etc.
 

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Great post Grumpy-b. The Ampera works perfectly for me because my daily commute is 37 miles....but if I need to go further, I can without blinking an eye. Yes, it's not perfect from an environmental POV, but for my current needs/budget it's perfect. Of course, the BMW i3 Rex would also have fitted the bill but it was an extra £5k and I would have had lots of surplus battery range each (working) day.

I was initially looking at an i3 BEV and hiring an ICE for journeys >80 miles...but changes in personal circumstances put paid to that idea.

I don't think my Ampera will be consigned to the scrap heap in 3 years...and by then a used i3 Rex or Golf GTE may be my car of choice.
 
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most people on this forum probably do less than 40miles per day
I imagine that if you get up to 70 at night, with a headwind and rain, a full load, and needing heating and demisting, that most BEVs would be pushed to do more than 50 miles, or even less on a single charge. I feel that we need much more range in BEVs for them to become useful vehicles. Part of the problem seems to be the regs which think that vehicle range can be computed down to a single figure. It would be better to see charts or tables of range at various speeds under various conditions.
 

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8pc per annum seems to be a number than comes up a lot: cheaper, lighter, more power density etc.

I get the same impression, that the next big thing is always around the corner. Some academics of my acquaintance in this area do hold out some hope, but hedge by saying "a decade away". Metal-air seems to be the closest...
 

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A decade ago I bought my nickel cadmium battery driven Citroen Berlingo Electrique. It managed 60 miles per charge at best. At that time people would say on the Yahoo email discussion list "if only we had batteries that could drive 100 miles per charge".

So forgive me if from where I sit in my Nissan Leaf the promised land has come! 114 miles from a single charge at best, over 90 miles in horrendous rain against a headwind in January in Norfolk to get to the next rapid charger, using demisters. Yes it was driving frugally and in a way many people would not choose to drive. But for me it HAS been possible.

Do not want to be too Pollyanna about this. I remember the promised Aluminium batteries promising 800 miles range from the Finnish inventor who won the Frost and Sullivan prize that came to nothing. And I remember the promised Compressed Air car from Formula 1 linked Guy Negre. What I have learnt from this is that if it looks too good to be true....particularly if it is linked to vested interests or the petro chemical industry....it probably is

But I also know the importance of realistic hopes and dreams in making change even possible.

For myself, I hope for the advances in the anode design promised. This would release existing unusable capacity....quite a lot of miles.....that is not used currently in Lithium to protect the life of the battery. I also hope that the promise of self healing materials leads to battery anodes you don't have to replace, can fully charge to 100%.

I also hope for graphene which in trials is exceeding the theorised possible qualities....no one is sure why yet. But could lead to a paradigm shift.

Remember, Nissan have said publicly the next Leaf will have a range of 200 miles. Tesla promise their model 3 at Leaf prices with a range of 200 miles by 2016. They have a habit of delivering on their promises.

Be (realistically) hopefully! As the Maori proverb says....and quantum physics may support...."We think our future into being".
 

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Sorry, Steve - you said it.

"ATTACH THE EXIDE-12V-BATTERY-FROM-A-1975-VAUXHALL-VIVA OF SHAME!"

You can only take it off and pass it on when someone uses the phrase "Supercharger" :cool:
 

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Have worked too long on myself in my training as a psychologist to succumb to labels of shame Mark....:)
I would expect nothing less. As it goes I do hold out some hope for Graphene, because it comes up *everywhere* in R&D conversations outside the office. But I'm almost hedging against myself because it can't possibly be a panacea, can it? But imagine it is...

What's your hourly rate again?
 

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Too little for a senior utility exec to notice....;)

Yes I know what you mean it does seem to solve "everything" along with 3d printing. And some are even putting the two in the same sentence which would take us way over the event horizon into as yet unimagined science fiction....

I would refine what I said to anode developments being the hope and graphene being the not quite impossible dream.....
 

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I read something about being able to refill your battery with charged electrolytes in a couple of years. I've no idea if that's even possible, but it sounded brilliant... (If a bit dangerous?)
It is perfectly possible, just Google for flow batteries. The problem though is that the Wh/kg for a flow battery is much lower than for a lithium battery so they are most practical in situations where weight doesn't matter such to provide backup in renewable power generation.
 

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Flow batteries are seductive, but unless there is agreement about the electrolyte there is going to be an unresolvable issue of supply. We have had innumerable wonder battery announcements and yet we remain in a metal hydride generation with extensive & enthusiastic refinement which will still produce benefits for some time yet.
 

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im not vastly gifted when it comes to electronic and electrical science, but taking note of other bits of technology, could there be ways of making components of the car more energy efficient? with less drain on the batteries, the range could be extended and in combination with battery development should see gradual range increases.

I do also wonder about tesla opening up its battery patents. does anyone else think they have something much bigger in the pipeline?
The biggest draw on power at motorway speeds is how much energy is needed to push air out of the way. Very roughly a Leaf at 70mph is using about 10,000 watts to push air, a few (~3,000) to roll along the ground, and a further 2,000 or so is getting lost in heat, noise, and accessories. With numbers like that, swapping 50 watts of halogen lights for 20 watts of led is just a drop in the ocean. The best way to improve range on a vehicle like the Leaf is to improve it's aerodynamics. Matching the Prius or Model S would get motorway range close to 100 miles, and matching the EV1 would get us into the 120s.
 

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Maybe there is a breakthrough out there waiting to be discovered like the equivalent of super cavitation but in air, achieving laminar flow or having an inflatable tail sock for motorway cruising. Halving drag would make an amazing difference.

Wonder what the efficiency of the model E would be if it had the same drag coefficient as an S but the drag area of a ford focus and a 50% lighter battery. Tesla will already have these calculations in play.

Super cavitation
http://en.m.wikipedia.org/wiki/Supercavitation

Laminar Flow
http://www.nasa.gov/connect/chat/laminar_flow_chat.html#.U-UwG9q9KK0

Tail sock
http://www.aolcdn.com/ch_autos/20100105_boat-tailed-car_614mz.jpg
Edit: better looking pic
http://www.speedace.info/automotive_directory/car_images/honda_fc_sport_car_concept_design_aerodynamic_tail.jpg

I also read some where that with rear wheel steering it would be possible to slightly point a Prius into any sidewinds it increases efficiency further, problem is it would mess with both the drivers head and other road users.
 

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Remember, Nissan have said publicly the next Leaf will have a range of 200 miles.
Did they. I know they have said they're working towards that kind of range, but I'm not sure I've seen them explicitly state that is for the next car? Do you have a reference?

Tesla promise their model 3 at Leaf prices with a range of 200 miles by 2016. They have a habit of delivering on their promises.
Though deliveries in 2017 realistically. And no doubt that will be US, so I wonder when in UK. mid 2017? I do hope they deliver on this
 

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The man I spoke to by chance from Nissan head office confirmed it....previously in the press a senior exec from Nissan anmoumced the 200 range planned, reported in Transport Evolved
 

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The man I spoke to by chance from Nissan head office confirmed it....previously in the press a senior exec from Nissan anmoumced the 200 range planned, reported in Transport Evolved
Bear in mind that 200miles will compare to the current range of 124miles...
 
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