Army scientists have developed a new material that could enable lithium-ion batteries to perform at an unprecedented five volts as part of research to create improved power sources for the military.
Researchers at the US Army Research Laboratory have for years been studying how the components of batteries interact to develop a new material that, when added to a battery’s electrolyte, increases the energy density of batteries 30 percent, according to the Army. The material is one of several additives electrochemical researchers at the lab have discovered.
The breakthrough is part of ongoing work by the Army to reduce the amount of weight soldiers carry by reducing the weight of power sources such as batteries, Dr. Kang Xu, electrochemistry branch, US Army Research Laboratory, told Design News.
Kang Xu, an Army Research Laboratory scientist, is one of the inventors responsible for a 30-percent increase in energy density in lithium batteries. The work is part of ongoing research to increase the energy of batteries while lowering their weight, to reduce the burden soldiers carry in the field. (Source: Army)
Soldiers can carry up to 32lb of batteries in their packs, and the lithium-ion batteries they use now are typically non-rechargeable and contain 4.1 to 4.2 volt cells, Xu said. He and other researchers have discovered an additive that increases the energy of these batteries into the 5-volt range.
The new material, designed and synthesized by researchers, can break down into small F-Alkyl radicals that deactivate the oxidative catalytic centers on cathode surfaces. This process, called passivation, “prevents the bulk electrolyte components (salt, solvents) to be oxidized, and stabilizes the battery operation without these parasitic reactions,” allowing for less weight and more energy from the batteries.
The batteries now operate with two different cathode chemistries -- 4.6V (LiNiMnO4) and 4.8V (LiCoPO4) -- resulting in about a 30 percent energy density increase. However, the actual increase is dependent on a number of factors, including “the weight of packaging, amount of electrolytes used, and other parasitic weights,” Xu said.
"In general, increases in energy density are equivalent to a reduction of weight if the same amount of energy is considered. So the 5V battery can lead to either more energy in the same battery pack or less weight for a pack with the same energy."
So far, Army researchers have come up with eight additives belonging to three different families of compounds and are working on patents for several of them. All told, the work is a great leap forward that represents a “major energy increase,” Xu said. However, “there is still a long way for 5V batteries to make it into soldiers’ packs.”
While this is very good news it's exaggerated a fair amount it seems. Running present Li batts at 4+ volts will destroy their life if charged above that much and left there.
Calling them by their max charge voltage vs actual load voltage isn't fair. Most li load voltages are 3.2-3.7 depending on version.
Plus once the battery is under load the voltage will drop 15-20% or so. I'd like some more data to see just how good it is under load and load/.voltage curves, etc so one can properly evaluate it.
I also don't believe the 30lbs of batteries regular soldiers carry is true. If it is one would be far better off carrying a generator of some type instead.
Here's another example of the military developing technology that also applies to the civilian world. It's also good to see the researchers are working to improve power without adding more weight.
As much as I would like to complain about govt. spending just may be Dr Xu has something.
I was told by an upper level DOE guy at their annual Fuel Cell Seminar a few years ago that the majority of the weight that soldiers carry IS batteries. The next item is food and water. If for example a sniper in Afganistan has to sit on top of a mountain for a few days he needs power for his radios, night vision, etc. A generator is a problem because most technologies make noise when they are operating. Even a fuel cell needs plumbing, fans, etc that are a problem to design to be absolutely silent.
Robat, a sniper left on a hilltop for days isn't a regular load. But you make my point exactly that a generator is nessasary. It's probably the best use of a foolcell as such low level power needs is easily done by a small 10-50 wt fuelcell like are available to power laptops.
Next a solar panel or small wind/rivergen weighing a lb or 2 could supply needed power. And can be made stealth.
If hiking or while sitting, a foot/leg, gravity, etc motion generator is doable.
The best way is reducing power needs by more eff equipment because like on the grid, the power you don't use is the cheapest of all.
And why are soldier carrying such loads degrading their performance? Why not have hip hitched cart/packframe carrying it so the soldier doesn't have to hold up 100lbs they do too often, just pulling it instead. If it's a tent/bed made from kevlar it eliminates those and provides cover even when caught in the open at no extra weight.
If you add the "balance of plant" to the fuel cell i.e. air supply, fuel tank, pumps, valves, converters, inverters, etc. it isn't necessarily the most efficient source of power. The only reason that the shuttles, etc used them was due to the tons of H2 they had to have anyway for other things (like the big burner at the bottom).
The fuel cells only real advantage is that of being a battery that can be recharged instantly (assuming that their is a handy H2 source around your tent.
If you carry methanol the efficiency is a small fraction of that of a pure H2 cell. If you carry hydrogen it has to either be compressed (very low density storage), liquid (cryogenic problems) or hydride (weight problems).
Maybe solid oxide might work because it will run off most anything but operates at pretty high temps.
Army research scientists are working on patents for this? Does this mean that the US government will license the technology for civillian applications, or that non-US military contract manufacturers can just forget it?
I wasn't able to discern if these types of additives are also being tried on rechargeable battery technology too. (I'm sure experimentation is being done in this area also.)
By experimenting with the photovoltaic reaction in solar cells, researchers at MIT have made a breakthrough in energy efficiency that significantly pushes the boundaries of current commercial cells on the market.
In a world that's going green, industrial operations have a problem: Their processes involve materials that are potentially toxic, flammable, corrosive, or reactive. If improperly managed, this can precipitate dangerous health and environmental consequences.
With LEDs dropping in price virtually every year, automakers have begun employing them, not only on luxury vehicles, but on entry-level models, as well.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
3 
