Sumitomo Electric accelerating development efforts toward mass production of Aluminum-Celmet; claims calculated 1.5 to 3x boost in battery capacity
29 June 2011
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| Aluminum-Celmet (40x) Click to enlarge. |
Sumitomo Electric Industries, Ltd., having newly developed its porous aluminum Aluminum-Celmet, has set up a small-scale production line at its Osaka Works to accelerate development efforts toward mass production of the new material. Aluminum-Celmet can be used to significantly improve the capacity of lithium-ion secondary batteries and capacitors, Sumitomo says.
Celmet is a porous metal made from nickel or nickel chrome alloy. The porous metal manufacturing process comprises electro-conductive coating to plastic foam, followed by nickel plating and plastic foam removal by heat treatment. Celmet’s features include high porosity (up to 98%), considerably higher than other porous metals, such as nonwoven metal fabric and foam metal; it also features a three-dimensional mesh-like structure that forms interconnected, open and spherical pores. Moreover, it is easy to process the porous metal into various shapes by cutting and stamping.
These features lead to favorable filling, retaining and current-collecting performance, when used with an active material. As such, Celmet has recently been adopted as a positive electrode current collector in hybrid vehicle nickel-hydrogen batteries.
Sumitomo recently developed porous aluminum Aluminum-Celmet materials, using processes similar to those used for producing nickel Celmet.
In addition to sharing the high porosity feature of Celmet, Aluminum-Celmet offers lightness (the specific gravity of aluminum is about one-third that of nickel) and greater electrical conductivity (or low electrical resistivity, less than half that of nickel). Furthermore, Aluminum-Celmet offers excellent corrosion resistance. These features make it suitable for use in lithium-ion and other secondary batteries operating at high charge/discharge voltages, for which Celmet made from nickel is not suitable. Aluminum-Celmet can also be used for current collectors in capacitors.
The positive electrode current collector in a conventional lithium-ion secondary battery is made from aluminum foil, while the negative electrode current collector is made from copper foil. Replacing the aluminum foil with Aluminum-Celmet increases the amount of positive active material per unit area.
Sumitomo Electric’s trial calculations indicate that in the case of automotive onboard battery packs, such replacement will increase battery capacity 1.5 to 3 times. Alternatively, with no change in capacity, battery volume can be reduced to one-third to two-thirds. These changes afford such benefits as reduced footprint of home-use storage batteries for power generated by solar and other natural sources, as well as by fuel cells.
In conventional capacitors, both positive and negative current collectors are made from aluminum foil. Use of Aluminum-Celmet instead improves the capacity and reduces the footprint, as with lithium-ion batteries.
Sumitomo is targeting improving Aluminum-Celmet for commercialization and mass production for lithium-ion battery and capacitor current collector applications.
(A hat-tip to GreenPlease!)
This promising technology should be more actively promoted and pushed as one the possible way to get affordable batteries for highway BEVs.
Posted by: HarveyD | 29 June 2011 at 01:49 PM
"Sumitomo Electric’s trial calculations indicate that in the case of automotive onboard battery packs, such replacement will increase battery capacity 1.5 to 3 times. Alternatively, with no change in capacity, battery volume can be reduced to one-third to two-thirds. These changes afford such benefits as reduced footprint of home-use storage batteries for power generated by solar and other natural sources, as well as by fuel cells." -
Outstanding, if true, economic, scale-able, mass-produce-able, and whatever else keeps these material advances for years from the market and product integration(silicon wire anodes, 10X faster re/charging electrode coatings, 3D batteries, etc, etc).
Meanwhile, truly complex boundaries inside electronic chips fall and Moore's law still doubles performance every two years.
Posted by: kelly | 29 June 2011 at 01:50 PM
Batteries aren't subject to Moore's Law.
Posted by: Mannstein | 29 June 2011 at 02:16 PM
Batteries aren't subject to Moore's law, but they are a long way from optimized or even diminishing returns. Also, since we want to optimize power-to-weight, power-to-volume, life cycles, cost/Kwhr, with acceptable safety and environmental impact...we have many variables to tweak to be anywhere near pareto optimality.
Posted by: HealthyBreeze | 29 June 2011 at 02:24 PM
IMO, volumetric energy/power density isn't all that important among relevant chemistries for automotive batteries. The most encouraging thing to me is the weight reduction and the fact that this appears to be a "drop in" solution for existing li-ion batteries (I have an email in to Sumitomo with a whole list of questions).
Take the Tesla roadster's battery pack: 990lbs and 56kw/hr or roughly 56w/hr/lb. If energy density were increased by 50%, the pack would ~666lbs for a savings of ~330lbs. Considering that fewer cells would be necessary and thus less packaging material and connectors, the cost could be reduced by at least this amount.
Hopefully this is significant as it appears on paper.
Posted by: GreenPlease | 29 June 2011 at 03:53 PM
"Batteries aren't subject to Moore's Law." - nothing is, since it's not a physical law. Yet some disciplines rapidly advance, others don't - kinda like measuring a lawyer's justice efficiency(not fee acceleration.)
Posted by: kelly | 29 June 2011 at 04:07 PM
the Moore law works for micro-processor since it just describe the capacity to just pack more densely transistor on Silicon, but you don't reinvent a new material each time. For batteries to double the energy density you have to invent a new material each time and that's what takes time, the time constant to double the energy density is measured more in decades than in months...
Posted by: Treehugger | 29 June 2011 at 06:32 PM
Tablets (improved e-books etc) are subject to new -Pad Law-. Their number multiply a few times every month or so instead of doubling every 18 months. Their performance has not reached the Star Trek Pad yet but it will sooner or latter.
Limited 3D versions are out and some manufacturers already offer 12-inch very high definition units with built-in SSD to store data, TV programs, films etc. Those powerful ultra thin units will replace many existing units such as TV, Phone, Play Box, Games, Cell Phone, Camera, written books, magazines, news papers, school books, black boards, note books, dictionaries, written records, medical historical data etc. Over ten thousand applications will be reached within a very short time frame.
Pad Law is here to stay but the pace (periodicity) has not been established yet. Will the principal progression factors be: Pad Sales, number of applications developed, number of tasks performed, number of other existing units replaced, number of human hours spent on a PAD, size of data communicated, size of data stored, tons of paper saved, tons of ink saved, number of jobs eliminated, power consumption reduction, etc etc. A multitude of factors will have to be used to measure progression of The PAD.
Posted by: HarveyD | 29 June 2011 at 07:05 PM