Toshiba Partnering with Mitsubishi To Develop Li-ion SCiB Battery Systems for EVs
02 July 2010
Toshiba Corporation announced that it is working with Mitsubishi Motors Corporation to bring its SCiB battery (earlier post) to electric vehicles (EVs). The SCiB is Toshiba’s rechargeable lithium-ion battery that combines high levels of safety with a long life and rapid recharging.
The use of new oxide-based materials in the current SCiB cells results in capacity loss after 3000 charge-discharge cycles of less than 10%; SCiB cells achieve more than 6000 charge-discharge cycles. More than 90% of the SCiB cell capacity can be charged in just 5 minutes using a large charging current (max. 50A).
A SCiB module now under development that houses the SCiB cells optimizes usage of individual cells and this, along with the long life cycle of the SCiB, adds to the overall durability of the battery over different cruising distances.
In bringing the SCiB to EV, Toshiba has developed a new original anode material and a new electrolyte that enhances both safety and rapid recharging.
Toshiba positions the SCiB as a new business with promising long term growth potential—and one that is already showing its versatility, as the SCiB has already been selected for an electric bicycle, an electric motorcycle, and as part of the power storage in a microgrid system.
Toshiba will produce SCiB for industrial applications, including EV and power storage, at Kashiwazaki Operations, a new facility in Niigata prefecture that is slated to start production in 2011. In the EV sector, Toshiba will move ahead by establishing an operating structure for promoting sales and marketing activities that will secure orders and allow it to respond quickly to market growth.
Mitsubishi has also earlier formed a joint venture with GS Yuasa—Lithium Energy Japan—to manufacture large-capacity and high-performance lithium-ion batteries. (Earlier post.)
Wonderful news! Toshiba's SCiB technology is streets ahead.
For anyone in a clod climate this battery has excellent performance down to -30C, and if you usually do not fast charge you should get 12,000 cycles out of the battery.
Toshiba rte it as having a 20 year life in an EV - more than the car.
Posted by: Davemart | 02 July 2010 at 03:25 AM
Meh. Many have some good performance numbers but it lacks the one thing next-gen batteries need – energy density.
Mitsubishi continues to disappoint.
Posted by: drivin98 | 02 July 2010 at 05:33 AM
driving98,
Perhaps you can do much better than Mitsubishi, but personally I think they have done a fine job in bringing the first purpose built electric car by a big manufacturer to the point where they are actually for sale now.
I have no idea of what you base your remarks on energy density on, but the Toshiba batteries now reach a respectable 100wh/kg, and are well in train to develop 150wh/kg:
http://e2af.com/interview/091009.shtml
As it says in this interview, the very high SOC of the chemistry with perhaps 95% of nominal capacity usable as against around 50-80% for most other chemistries also increases the effective usable energy content per kg.
Posted by: Davemart | 02 July 2010 at 05:55 AM
Thanks Davemart, there is an excellent article on the same site as to where the Japanese feel battery technology is going for the next 20 years:
http://e2af.com/review/090930.shtml
Posted by: clett | 02 July 2010 at 06:26 AM
The only problem with this battery seems to be very LOW energy density. However, it could be an excellent candidate for heavy vehicles (buses, trucks, locomotives, boats etc) where excess size and weight is a lesser problem.
Posted by: HarveyD | 02 July 2010 at 08:04 AM
Harvey D
Did you read the links I provided? If so on what basis do you claim a low energy density, and compared to what in terms of the actual usable energy per kilogram?
It is rather lower than the new Panasonic, admittedly, but as Toshiba remark in the very extensive links given, they feel that they are on a path to improve more rapidly in this respect than other chemistries.
The 100wh/kg they can do already together with the very good SOC would already enable as good or better performance kilo for kilo as the Leaf or iMiEV
Posted by: Davemart | 02 July 2010 at 08:10 AM
Davemart the high power battery is only 51 wh/kg The other batteries are much lower charge discharge rate.
Posted by: wintermane2000 | 02 July 2010 at 08:25 AM
DM:
Toshiba's battery energy density is still running about 50% of other top producers but their durability, quick charge/discharge and cold weather operation may be one of the best.
When Toshiba doubles the energy density (from 100/150+ to 200/300+ Wh/Kg range) it could be a winner. However, by that time, others will also double the energy density of their battery (form 200/300 to 400/600 Wh/Kg range)
Interesting technical competition ahead. Toshiba will no doubt become a major supplier.
Posted by: HarveyD | 02 July 2010 at 08:52 AM
wintermane:
Please provide the sources for your claim that the high power battery only provides 51 wh/kg, as this flatly contradicts the linked sources to the manufacturer that I have given.
Perhaps you are thinking of the 4.2ah battery, thge 20ah one is the one that is in question.
Harvey D
On what grounds do you expect other chemistries to further double their density to 400/600 Wh/kg?
AFAIK you start running into physical limits before then, and you need to switch to LiS or Li-O2 to get there.
150wh/kg should be enough for Toshiba to do a 200 mile nominal range car, given the very good SOC.
Posted by: Davemart | 02 July 2010 at 11:03 AM
12V Battery Pack SCiBTM TBP-0501
Nominal Voltage 12V
Nominal Capacity 4.0Ah
Max. Charging Current 8.4A
Max. Discharging Current 8.0A (continuous)
25A (within0.3s)
Size Approx. 145 x 109 x 48mm
Weight Approx. 1.0kg
http://www.scib.jp/en/product/spec.htm
It has good power, but not such great energy density.
Posted by: SJC | 02 July 2010 at 12:38 PM
SJC:
'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
this is the battery for EV use - the one you are looking at is for electric bikes etc.
Posted by: Davemart | 02 July 2010 at 01:10 PM
Dave:
If Toshiba can double the energy density, so can others in the same time frame. However, many others are there already and Toshiba is promising higher energy density for 2011.
Posted by: HarveyD | 02 July 2010 at 02:38 PM
Harvey D,
It seems tough here to get folks either to read links or reference their comments!
I accepted that the Panasonic battery has a higher density, but queried your claim that they could as readily double that again as Toshiba can catch up:
'On what grounds do you expect other chemistries to further double their density to 400/600 Wh/kg?
AFAIK you start running into physical limits before then, and you need to switch to LiS or Li-O2 to get there.'
So you have sources or back-ups of any sort for your claim?
I have referenced Toshiba's achieved 100wh/kg ready for production, with 150wh/kg as their next target.
Posted by: Davemart | 02 July 2010 at 02:50 PM
Dave:
You can rest assured that others will not stand still while Toshiba tries to double the energy density of its excellent batteries. Electrovaya is already over 300 Wh/Kg.
Posted by: HarveyD | 02 July 2010 at 06:04 PM
Davemart here is the important bit you missed...
http://e2af.com/interview/images/091009/img_06.jpg
Notice how the 3900 w/kg battery and the 100 wh/kg battery are two VERY different batteries?
Notice how the future 150 wh/kg battery is vastly lower power density then the 20 ah model?
Also note the 7000 cycle lifespan was only on the high power battery they never talk about the lifespan of the high energy models.
Posted by: wintermane2000 | 02 July 2010 at 06:42 PM
Wintermane,
I have no idea how you manage to interpret the figure in the way you do!
There are two battery types under consideration, the PHEV high power low density one, which is the one with 3900w/kg, and the lower power, higher energy density one for EV's.
They state:
'Future development will be focused on the high energy type'
If you look at the diagram. that clearly shows the 20ah battery is of this type, as are both the 100kw/kg model and the projected 150wh/kg.
Since the battery is much bigger in an EV, there is no need to go for really high power output per kilogram, the EV model is plenty powerful enough.
The longevity figures I gave apply to the high energy density variant - have another look at the links provided
The 4.2Ah variant is part of the high energy density family as is the 20Ah.
The 3.0Ah is part of the high-power family.
Since you seem to somehow miss it ;-) here is yet another link confirming that the high energy variant looses just 10% of capacity after 3,000 cycles, which a cross-reference to the graphs I have already linked to shows is on the depletion curve to 82% capacity after 6,000 cycles:
'At September's Ceatec show in Japan Toshiba demonstrated a laptop running on an SCIB. The battery will keep its performance through up to 6,000 recharges -- more than ten times that of typical Lithium Ion batteries -- meaning a laptop should be able to run its lifetime on the SCIB without need to replace the battery. Due to its design it is also much less likely to catch fire or short circuit if crushed or damaged.'
http://www.pcworld.com/article/156011/toshiba_plans_big_production_jump_for_fast_charging_battery.html
And here they give they are clearly referring to car use:
'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
Have you a source for your contention that this only applies to the high power variant?
Posted by: Davemart | 03 July 2010 at 03:02 AM
Market leader A123's 20Ah (prismatic nLFP) cell is 50% greater than that of the old 26650 cylindrical cell or about 164Wh/kg.
All this competition in battery chemistry is excellent for growing jobs and returning manufacturing to domestic sources. One of the best effects of electrification of transport will be de-centralization of manufacturing away from low-cost regions. And patent infringement issues will make low-cost products less attractive and far more expensive in the long term.
Posted by: Reel$$ | 03 July 2010 at 06:25 AM
Sorry Davemart, didn't mean to hurt your fanboy feelings (excuse the dig) but the fact remains that 100wh/kg just isn't that impressive when others, Panasonic, Boston Power and others have 80% to 100+% more. SCib might be good for some applications (if they are cheaper than A123)but what the Mitsubishi needs (in their i MiEV, at least)is increased range that comes from more energy dense cells.
Sorry for being down on Mitsubishi, and I understand the reasons behind their lack of market aggressiveness, but I'm just calling it as I see it.
Your mileage may vary.
Posted by: drivin98 | 03 July 2010 at 07:33 AM
The different lithium chemistries have trade offs. Some charge and discharge quickly, some have great capacity for their weight and size. It is the goal of the market to find the right battery for the application. Saying that one is "better" than another is meaningless until we all define what better is.
Posted by: SJC | 03 July 2010 at 08:44 AM
Davemart I see now an article I was reading had the 3.0 and 4.2 variants switched around.
Still I think the 150 wh/kg pack isnt designed for the kinds of ev you like I think its for much larger evs mid sized and larger.
Posted by: wintermane2000 | 03 July 2010 at 10:31 AM
I find it is difficult to nail down the theoretical limits of different battery chemistries, but the none-too informative links I found seemed to indicate that there may be some sort of energy density barrier for lithium titanate at around 175wh/kg.
Other chemistries are around 300wh/kg, although the idea that they can be pushed much further to, say, 600wh/kg seems fanciful - you need totally different chemistries like LiS to do that.
I should also make it clear that 150 Wh/kg is a target for Toshiba, not an achievement.
So at the moment a performance which compares to that of the Leaf is on the cards, especially in view of the very good SOC.
You get the additional benefit of very long life, super fast charge capability etc.
This sounds good for many commercial vehicles, but unless Toshiba can greatly increase energy density the 300wh/kg of other chemistries seem likely to win out for personal vehicles, particularly since the auto makers may be less than enthralled by the prospect of putting a battery in cars which lasts more or less forever.
Personally, a Leaf like car which can do 100-150 miles and where you don't have to change the battery before the car falls apart would appeal, but it is perhaps doubtful if we will get it.
Posted by: Davemart | 03 July 2010 at 01:07 PM
Dave:
I almost agree with you, specially about the relative energy density from different lithium batteries. In principle, lithium batteries energy density should increase at about 8%/year or double every 10 years or so until it cannot be pushed any further. No real breakthrough is required. Normal evolution (improved electrodes, refined manufacturing etc etc) should get lithium batteries from 300 Wh/Kg to about 600 Wh/Kg by 2020 or shortly thereafter. The next evolution step, from 600 Wh/Kg to 1200 Wh/Kg may take a bit longer or may require minor breakthroughs but it will come by 2030 or shortly thereafter. To go from 1100/1200 Wh/Kg to 2400 Wh/Kg will require a major breakthrough and many years of aggressive R & D but it is not impossible. That's what is required to replace most if not all ICE cars and light trucks.
Posted by: HarveyD | 03 July 2010 at 07:55 PM
I think what is missing here is a true apples to apples comparison. We should really be talking "usable energy density".
It's more impressive to say a certain battery chemistry has 300Wh/kg than it is to realize it can only have 150Wh/kg of "USABLE" energy if it can only cycle between 90% and 50% SOC without damaging the battery.
I'm as guilty as everyone else, but you have to admit that we have a habit of only looking at the raw numbers that everyone publishes to promote their latest battery...without asking the hard questions:
1) What range can it support without shortening battery life (ie can it only go to 40% and back up to 90% with no damage on a regular basis)
2) How many kWh can does it supply between that low end and high end SOC (which is the actual usable portion)
3) How many cycles can it do in that SOC range
4) What is it's cost per kWh
5) How quickly can it handle rapid recharge with no damage
Truthfully, there is also the rest of a matrix that should be filled out if you want to compare:
6) What is the kW/kg (power)
7) What is the shelf life
8) What is the operating temperature range
Those numbers are all related and we shouldn't be comparing them to each other across batteries, one number at a time, because they are meaningless without a context. And even which ones are important changes with an EV vs. HEV
Posted by: DaveD | 03 July 2010 at 09:22 PM
DaveD,
Good points, that is one of the reasons GM has carefully picked its batteries suppliers for the Volt over the years. There are lots of claims, but when the corporate future rests on the quality of the components, you choose wisely or you do not get to choose again.
Posted by: SJC | 03 July 2010 at 09:50 PM
Worse still many batteries only count the PEAK power output not the constant. Back a few months someone was talking about using a battery for evs and I pointed out.. the battery only managed 2 amps constant discharge rate.... That ment the entioe pack they had envisioned had as much power as a weed wacker....
Posted by: wintermane2000 | 04 July 2010 at 03:12 AM