New Battery Technology

[Panzer1]

New discoveries could help hikers by increasing battery life and reducing weight. Flashlights, cell phones, MP3 players, radios, ect could all last longer on the trail. See article from "Scientific American" below:

Panzer

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Carbon Nanotubes Boost Power of Lithium Battery

A new battery demonstrated a power output 10 times higher, for its size, than what is expected of a conventional rechargeable lithium battery

By Darius Dixon and Climatewire




BETTER BATTERIES: Scientists have used carbon nanotubes to increase the capacity and power output of conventional rechargeable lithium batteries.
ISTOCKPHOTO


Imagine that the same rechargeable battery in your cell phone could power a device that requires 10 times the energy. That possibility may be closer than you think.
A battery created by researchers at Massachusetts Institute of Technology demonstrated an increased capacity for charge by roughly a third and a power output 10 times higher, for its size, than what is expected of a conventional rechargeable lithium battery. The results were published yesterday in Nature Nanotechnology.
The research team, led by Yang Shao-Horn, an associate professor of materials science and mechanical engineering, and Paula Hammond, professor of chemical engineering at MIT, achieved this by creating an entirely new kind of electrode -- in this case, by modifying the positive end of the conventional battery, which is called the cathode.
The collaboration began through graduate student Seung Woo Lee, studying fuel cells, who was advised by both Shao-Horn and Hammond. Lee defended his doctoral dissertation this spring.
Using commercially available carbon nanotubes -- hollow cylinders 50,000 times thinner than a human hair but composed of carbon atoms -- the team fabricated the cathode entirely out of the nanotubes put down in layers.
The large surface area of a nanotube allows it to store more charge than other types of carbon, such as graphite, but previous battery fabrication methods tended to obscure these surfaces.
Using the exposed surfaces allows more charge to be stored -- increasing capacity -- while also letting those charges migrate more easily -- increasing power.
The findings of this research challenge the conventional wisdom about what materials could be used in the cathode of a battery. It also stimulates discussion about what such powerful batteries could be used for.
Small scale experiments so far
Increased power output makes for a great capacitor as well, by efficiently storing charge and delivering that energy precisely when it is needed. Their work, Shao-Horn said, could "lead to a device with performance that bridges batteries and electrochemical capacitors."
So far, the thickest cathode the group has made for these experiments is only 3 micrometers -- 3 one-thousandths of a millimeter. This is tiny when compared to conventional lithium-ion batteries that have electrodes roughly 100 to 200 micrometers thick.
In their present form, Shao-Horn said, their cathode "could be ideal for microelectronic devices."
But these battery-capacitors are also useful in a number of other applications such as emergency power, "energy capture and power assist in cars, trucks and machinery requiring many start-stop cycles," said Shao-Horn. Successfully scaling up this design could dramatically reduce the inefficiencies in future lithium-ion batteries.
However, Shao-Horn preferred to err on the side of caution when peering into the future of this new technology, saying they are only just beginning to understand the underlying chemistry involved.
"Further work is required," said Shao-Horn, "to demonstrate that power and energy performance is maintained with thicker electrodes." A crucial next step of this research is to demonstrate an electrode with a thickness of 50 micrometers -- more than 10 times the size of what they made for their experiments.
The next phase is scaling it up
Doing so would allow the researchers to test whether the electrical properties of the carbon nanotubes can be successfully scaled up to greater and greater thicknesses. Potentially, Shao-Horn said, there is "no limit" on thickness. But in order to do this, Hammond's expertise in biomaterials will be essential.

[DapperD]

I know some of these headlamps, cameras, etc...cannot use Lithium batteries. They can burn them out. One needs to be sure the manufacturer states that this is OK, as they are all different.

[Arden]

Also, the charging circuitry in each device is designed for a specific battery/type. Using the wrong battery can cause it to either overcharge and possibly explode, or undercharge and fail to provide the service it was designed for.

The devices that will eventually use these new batteries will be designed specifically for them. I doubt we will be seeing any of these anytime soon though.

Arden

[Panzer1]

I doubt we will be seeing any of these anytime soon though.

I think your right. But someday it might be possible to do an entire thru-hike without needing changing the batteries in your flashlight.

Panzer

[Arden]

I think your right. But someday it might be possible to do an entire thru-hike without needing changing the batteries in your flashlight.

Panzer

Or just do the hike without a light

[couscous]

I switched to carrying a 9v pak-lite 5-6 years ago that provides 1200 hours on low with a lithium battery. Depends how much you use your light, but that could easily do an entire thru-hike without changing batteries. http://www.9voltlight.com/inc/sdetail/61