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Discussion Starter #1 (Edited)
https://www.reuters.com/article/us-...r-battery-to-power-cars-idUSKCN0SN2NH20151029

Researchers at the University of Cambridge on Thursday announced the creation of a laboratory demonstration model of a lithium-oxygen battery that overcomes many of the barriers that have held back the development of this technology.


They said the battery boasts very high energy density, is about 93 percent efficient - better than previous efforts - and can be recharged more than 2,000 times.

Clare Grey, a Cambridge professor of materials chemistry who led the research, called it “a step towards a practical battery, albeit with many hurdles ahead.” The researchers said it could be more than a decade before a practical lithium-oxygen battery is ready, in part because the battery’s ability to charge and discharge is too low.

In cars, the range for a compact, fully charged battery has been unable to reach that of a full tank of gasoline in a regular engine because current lithium-ion batteries do not pack that kind of power punch.

The lithium-ion rechargeable battery, first introduced in 1991, helped power the portable electronics revolution including laptops and smartphones as well as powering some vehicles.

Lithium-oxygen batteries, also called lithium-air batteries, have the potential to deliver the desired power thanks to a high energy density - a measure of energy stored for a given weight - that could be 10 times that of lithium-ion batteries and approach that of gasoline. They also could be a fifth the cost and a fifth the weight of lithium-ion batteries.

But problems have beset lithium-oxygen batteries that affect their capacity and lifetime, including troublesome efficiency, performance, chemical reaction and potential safety issues and the limitation of needing pure oxygen rather than plain old air.

The Cambridge demonstrator battery employs different chemistry than previous work on lithium-air batteries, for example using lithium hydroxide rather than lithium peroxide. It also uses an electrode made of graphene, a form of carbon. The result was a more stable and efficient battery.

Grey said it is too early to gauge lithium-oxygen battery range limits in vehicles.

Intellectual property from the research is owned by Cambridge Enterprises, the university’s commercialization arm, and has been patented, Grey said.

The research was published in the journal Science.
 

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A battery does not need to reach the power density of Gas as the electric motor battery package is about 90% over all.
An IC engine on gas is about 20 to 25% over all. So the batteries only needs to be 3.0kw per kilo to match with gas.
This is a about quarter of the max theoretical max of Lithium Air so it does not need to match the density of gas and I believe an achievable goal.
So when batteries hit this level and fast charging gas is dead.
 

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Metal air batteries would theoretically be the best batteries. Sill a long ways off. The next improvements would seem to be the solid state cells which replace the liquid electrolytes with a solid material. That would be a huge advance for many reasons, not just energy density, and it seem likely we'll see them in the next several years.
 

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Dang, I wonder what would happen if we could get all these people in the same lab?

I really hate too poo-poo real scientists at work but...... 2000 cycles? Isn't that a bit underwhelming?
 

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Dang, I wonder what would happen if we could get all these people in the same lab?

I really hate too poo-poo real scientists at work but...... 2000 cycles? Isn't that a bit underwhelming?
Depends on application. The chemistry in the Volt makes batteries that "rate" to 500-1200 cycles and exceptional cartakeing makes them last 4000+. Doubling the starting point may well mean similar caretaking gets 8000 cycles out. But even then, that's more than the rest of the car is going to last. 2000 cycles of 250 miles is 500,000 miles. How long will it take you to drive that far?
 

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Depends on application. The chemistry in the Volt makes batteries that "rate" to 500-1200 cycles and exceptional cartakeing makes them last 4000+. Doubling the starting point may well mean similar caretaking gets 8000 cycles out. But even then, that's more than the rest of the car is going to last. 2000 cycles of 250 miles is 500,000 miles. How long will it take you to drive that far?
Hmm, good points there. I wonder if the same babying of the battery would help this type.
 
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