Mitsubishi Motors selects Toshiba SCiB for EVs
17 June 2011
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| 20Ah SCiB cell. Click to enlarge. |
Mitsubishi Motors Corporation has selected Toshiba Corporation’s SCiB battery (earlier post) to power two new models of electric vehicles (EV), the i-MiEV and MINICAB-MiEV. In July 2010, the two companies had announced they were working together to bring the SCiB batteries to EVs. (Earlier post.)
With lithium titanate oxide in the anode, the SCiB offers a high level operating safety, long life and rapid charging. The use of lithium titanate oxide also significantly reduces the possibility of a puncture in the separator between the anode and cathode, so minimizing the risk of them coming into contact and short circuiting, and maintains battery performance levels even in severe operating conditions, including very low temperatures, Toshiba says.
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| SCiB module for automotive use. Click to enlarge. |
The SCiB supports 2.5 times more charge/discharge cycles than a typical lithium-ion battery, according to Toshiba. Charged with the highest current available with CHAdeMO, an SCiB reaches about 80% of full capacity in some 15 minutes, about 50% in 10 minutes and about 25% in 5 minutes for a 10 kWh pack—half the times of a typical lithium-ion battery charged under the same conditions. The SCiB also generates little heat while recharging, eliminating the need for power to cool the battery module.
The SCiB also offers a higher effective capacity than a typical lithium-ion battery, in that more of the stored charge can be used safely before recharging the battery. This, combined with highly efficient regenerative charging during braking or coasting downhill, allows the SCiB to deliver 1.7 times the driving distance per level of charge of a typical lithium-ion battery. This will allow for installation of smaller battery modules in vehicles and contribute to lower EV prices. The SCiB also offers high level performance in a wide range of temperatures, and continues to support rapid charging and excellent power output at temperatures as low as -30ºC.
The SCiB for Mitsubishi’s new EV will be manufactured at Toshiba’s Kashiwazaki Operations in Niigata prefecture, northwest Japan, a new facility dedicated to production of SCiB that came on line in February this year. Toshiba will seek to establish a plant operating structure able to respond quickly to market growth as the basis for expanding the SCiB business for EV, including hybrid and plug-in hybrid EVs.
As the automotive industry responds to concerns about global warming by developing a new generation of EVs, Toshiba is promoting advances in essential automotive technologies, from dedicated on-board control systems to batteries and Intelligent Traffic Systems. In automotive-related power electronics technologies, Toshiba is targeting net sales of 800 billion yen (US$10 billion) by fiscal year 2015 from its concentration on motors, inverters and SCiB.
Awesome! Let's hope that Mitsubishi put SCiB in the ASX PHEV hybrid crossover too:
'Mitsubishi is likely to offer a plug-in hybrid version of the compact ASX sports utility vehicle as its second electric vehicle, after the launch in New Zealand next month of the i-MiEV, the battery-powered version of the company's small iCity hatchback.'
http://www.nzherald.co.nz/motoring/news/article.cfm?c_id=9&objectid=10732003
It looks like this will have a 50km electric range.
Posted by: Davemart | 17 June 2011 at 03:05 AM
It is a huge blow to GS Yuasa Corp that supplies the batteries of the current version of the iMiEV as it strongly signals that their battery technology is no longer competitive.
I find it very interesting that they intend to replace the 16 kWh GS battery of the iMiEV with a 10kWh battery from Toshiba and still claim the range is unchanged. Apparently usable energy in the new 10kWh battery is equal to usable energy in the 16 kWh GS battery.
I believe the energy density of the Toshiba battery is less than 90Wh/kg at the cell level so its true benefits are its superior cycle performance, power density, cold weather performance and better usable discharge range. Toshiba’s battery technology will never make it into a long-range BEV but I am certain Japan will get a very dense network of 50kW chargers in a few years (possible before 2016) and that will make it possible to use these kinds of short-range EVs everywhere without much worry about range anxiety.
Posted by: Account Deleted | 17 June 2011 at 03:10 AM
Henrik:
'As for EVs, we will begin to ship samples with the nominal capacity of 20Ah and the energy density of 100Wh/kg this fall. The energy density is sufficient for a small EV, but in order to drive a larger EV, the energy density needs to be raised to around 150Wh/kg. We are already working on this, and we are putting further efforts into research for EV batteries (Fig.6).'
http://e2af.com/interview/091009.shtml
The claim of 2.5 times more charge/discharge cycles also seems very conservative:
'Generally speaking, the capacity of a rechargeable battery declines along with cycles of charge and discharge. Conventional lithium-ion batteries are capable of 1,000 charge-discharge cycles, after which it will probably need replacing. SCiBTM batteries, however, can go through 6,000 charge-discharge cycles, after which they will still have a capacity of above 90%. Giving a high load by repetition of quick charging and discharging, SCiBTM batteries still have a capacity of over 80% after 6,000 charge-discharge cycles. (Fig.2)
For durable goods such as automobiles in use over years, batteries that have long service life bring significant merits in terms of cost of ownership. Assuming that some battery has a service life of 1,000 cycles and is charged every day, this means its replacement will need after around three years or so. In contrast, 6,000 cycles of SCiBTM service life means about 20 years. This is to say that the life of a battery is longer than that of an automobile itself.'
http://e2af.com/interview/091006.shtml
Posted by: Davemart | 17 June 2011 at 03:51 AM
Very informative source Davemart.
Posted by: Account Deleted | 17 June 2011 at 04:12 AM
Great news, all we need now is to get the energy density up a bit and it's goodbye to gasoline.
Any suggestions as to what can we do to bring lithium titanate energy density up to near carbon/cobalt based lithium levels, say, 200 WH/kg? Doping? Manganese? Vanadium?
Posted by: clett | 17 June 2011 at 07:43 AM
Sounds like a great battery for hybrid applications.
Posted by: Nick Lyons | 17 June 2011 at 08:42 AM
Presumably this is also the battery going into the ASX PHEV from Misubishi in 2012.
50 km electric only range
Posted by: Davemart | 17 June 2011 at 09:00 AM
This thread seems to be letting me post again. I was trying to say:
Mitsubishi are using the better performance of the Toshiba's at the moment to reduce battery capacity and hence costs.
Ignoring costs for a moment and looking at the range possible for the same weight as the Yausa pack, which has around the same energy density as the Toshibas then you could increase the range by 1.6 if a 16kwh SCiB were specified.
Ignoring also the hopelessly optimistic range estimates for the iMiEV based on the Japanese cycle and guessing that on the EPA cycle under which the Leaf gets 73 miles of range, the Mitsubishi might at present have a 60 mile range.
So with a 16kwh battery pack it could hit 96 miles.
If Toshiba successfully get to 150Wh/kg, then for the same weight it might hit around 144 miles of genuine range.
Pretty good, I reckon.
They hope to get it down to around $22,000 after subsidy by 2012 for the basic model, presumably.
Since you will never need to change the battery that sounds good to me.
Posted by: Davemart | 17 June 2011 at 09:03 AM
I always wondered why these Batteries where not used for HEV ? as they are more suited for fast and numerous charges and de-charges. Also I never found their energy density anywhere despite being on the market for quite some time
Posted by: Treehugger | 17 June 2011 at 09:34 AM
@Treehugger:
Toshiba have only just started to produce batteries with the right energy density for either HEV or BEV use.
They were previously limited to ~40wh/kg, jsut like the ones that Altairnano make and who use them in hybrid buses such as the Proterra.
Toyota has upped the energy density by increasing the voltage to 20v.
VW are also to use them, and the new energy density can be inferred here:
'Volkswagen in 2009 unveiled its Eup! commuter EV with production model expected in 2013. It has 18 kWh of lithium-ion batteries (mass 240 kg of total 1085 kg) giving an electric range of 130 km. A US version will be bigger and have 200 km range. It can get 80% charge in an hour or full charge in 5 hours from 230-volt system. It uses Toshiba's SCIB (Super Charge Ion Battery) technology which is resistant to short circuits. Solar panels on the roof run ancillary systems.'
http://www.world-nuclear.org/info/electricity_cars_inf120.html
That works out to around 75wh/kg at the battery level, about right for the 100wh/kg at the cell level Toshiba state in the links I have already given.
There will be two versions, one for BEV and one with more power density for HEV
Posted by: Davemart | 17 June 2011 at 09:47 AM
Sorry, my last should have read that Toshiba have increased the energy density by increasing the amperage:
'Now in production are high energy density 4.2 Ah cells. Additionally, Toshiba is aggressively pursuing a product roadmap focused on further increasing SCiB™ capacity, energy density, and power density. 20 Ah cells with the same characteristics will be available in 2011.'
http://www.toshiba.com/ind/data/tag_files/SCiB_Brochure_5383.pdf
Bottom right of the spec sheet.
Posted by: Davemart | 17 June 2011 at 10:03 AM
With low energy density but high power density, this battery would be a good companion to the ZEBRA battery or sodium-sulphur battery or a fuel powered range extender. ..HG..
Posted by: Henry Gibson | 17 June 2011 at 11:01 AM
HG:
I am not sure where you get the low energy density bit from.
The density at 100wh/kg at the cell level is comparable to the manganese spinel batteries used by Nissan, and their projected 150wh/kg is better.
The only batteries having significantly higher density are NMC batteries, but OTOH they cannot safely be discharged down to the same level as lithium titanate.
Posted by: Davemart | 17 June 2011 at 11:08 AM
Sorry but their energy density is crap. The Panasonics going into the Tesla Model S I believe are 240Wh/kg.
Fine if you want crappy range but I'm not impressed.
Posted by: drivin98 | 17 June 2011 at 12:17 PM
drivin98:
I'm not sure which bit of:
'The only batteries having significantly higher density are NMC batteries, but OTOH they cannot safely be discharged down to the same level as lithium titanate.'
you do not understand.
The lithium titanate batteries are certainly not bad for energy density when compared to those in current cars like the Leaf.
In addition the Panasonic batteries you refer to have problems even hitting a 500 cycle life, as against 6,000 for lithium titanate:
http://techon.nikkeibp.co.jp/article/HONSHI/20100223/180545/
Now the easiest way to stretch cycle life is to use less of the battery, as they really do not like deep discharge.
That is why the GS Yuasa ones the Toshiba's are replacing needed 16kwh to do the same job as the 10kwh of the Toshiba.
So reducing the power output by the same factor you come out to 150wh/kg equivalent, better than the current Toshibas but OTOH you still won't have a battery pack which will last the life of the car unlike the Toshibas.
If Toshiba manage 150wh/kg then since they only have to have a 5% reserve they will be on a par with the Panasonics for practical purposes - and last a lot longer with faster recharge.
Posted by: Davemart | 17 June 2011 at 01:03 PM
This is the trade off for quick charge. I like this battery and I think it will have its customers. People have to decide what is important, range, quick charge, battery life, price, weight, size or other factors.
Right now the car makers are deciding for them and hoping they are right. Maybe they have asked a sample group, but the results are not clear because the potential buying public wants it all. Never take something away from your customers, they do not want to prioritize a sacrifice and pay full price for it.
Posted by: SJC | 17 June 2011 at 01:54 PM
SJC:
Exactly what are you basing your claims of a trade off in range for the quick charge on?
I have detailed the figures, and they get as much range from a lower kwh than current batteries.
That is how they are able to swap the 16kwh of GS Yuasa batteries which are similar to those in the Volt or Leaf for 10kwh for the same range.
No sign of a trade off there.
Posted by: Davemart | 17 June 2011 at 02:45 PM
I am not going to debate this, it is obvious. If I want 200 mile range with these batteries they will weigh more and take up more room, at is obvious.
Posted by: SJC | 17 June 2011 at 02:55 PM
If you are not going to debate it, why are you commenting?
It is perfectly plain that if these batteries are getting the same range from 10kwh as the previous ones from 16kwh, they have an effective utilisable capacity of 1.6 times them, not less.
I have already commented on the far lower than is immediately clear disparity in utilisable energy between these and the superficially much more energetic Panasonics.
So do you have any basis at all for your claims,or are you just making random declarations which you are entirely unable to substantiate?
Posted by: Davemart | 17 June 2011 at 03:07 PM
We all comment for our own reasons, I do not have to explain those to you.
Posted by: SJC | 17 June 2011 at 03:09 PM
SJC,
Of course not. You can continue to make random statements which you are unable to back up in any way.
However it somewhat detracts from any use of the forum as a rational debating venue.
I suppose that is what trolls are for.
Posted by: Davemart | 17 June 2011 at 03:15 PM
Whatever, go forth and learn, do not expect others to educate you.
Posted by: SJC | 17 June 2011 at 03:28 PM
Yeah, invective is so much easier for you than trying to construct a rational argument, or confronting your prejudices.
I repeat: you add nothing to any constructive debate, and so consequently your contribution here is completely without value, being a pantomime argument of a child:
'No, it isn't!'
Don't worry, you have made your limitations clear, so I have given up expecting anything adult or logical from you.
Posted by: Davemart | 17 June 2011 at 03:37 PM
Scib is another wonder battery - I wonder where I can buy one and what the price is. Scibs have been in the news for years. Like writing EEstor or Firefly or Prieto or .. in the past, I've gotten no response/price - rather less a actual battery.
All I want is a few scib TB P-1001 24v or P-0501 12v batteries for testing.
Posted by: kelly | 17 June 2011 at 04:54 PM
Hi Kelly. They are concentrating on business customers at the moment. Here is the centre for NA sales:
http://www.incompliancemag.com/index.php?option=com_content&view=article&id=211:toshiba-establishes-north-american-sales-a-support-for-scibtm-battery&catid=23:products&Itemid=150
And here are the specs for their HEV high power and BEV high energy batteries - these are different to their normal 12V and 24V packs which are orientated to electric bikes etc I believe, although I am not sure about that.
http://e2af.com/interview/images/091009/img_06.jpg
Mitsubishi going by the price difference between their 10.5kwh pack version of the MiniCab and their 16wkh version of the same are charging customers $778kwh for them, but of course we don't know how much they are paying Toshiba.
Posted by: Davemart | 17 June 2011 at 05:16 PM