Lithium Polymer Batteries: A Review
by EcoGeek.org on 12.11.06
It's an information age we're living in, and thus, portable electronic devices are a luxury most of us either choose to live with, or have a hard time living without. Thus, we have become a race of people that have large amounts of energy stored in our pockets and on our laps. That luxury has environmental, financial and since they started exploding, personal risks involved. So we at TreeHugger thought it would be good to discuss the next step in power storage technology, the Lithium Polymer battery.
Lithium-ion batteries have taken over the portable electronics industry in the last few years. For every unit of energy they contain, they are lighter, cheaper, and smaller than other kinds of batteries. They don't suffer from the 'memory' effect that gave nickel batteries a bad name, they contain relatively few toxic metals and are fairly simple to recycle.
But, in the last year, several battery makers pushed the limits of energy density in Li-ion batteries too far. Li-ion batteries use organic solvents to suspend the lithium ions. In situations where the structure of the battery is compromised, that solvent can ignite and vent from the pressurized battery. The result is a dangerous and toxic fireworks display you can see in a video at the end of this article.
In response to the dangers of packing more power into a Li-ion battery pack, portable electronics makers are turning to lithium polymer batteries. You might see it abbreviated as Li-Po (yes, like the Chinese poet) or Li-poly, or you might see it in it's complete and extended form "lithium ion polymer batteries," they all mean the same thing.
The main advantage of Li-poly batteries that has been discussed in the press recently is their reluctance to explode under duress. They will explode if over-charged, like any other battery, but they can be banged around, punctured, dropped or run over with a car and still not explode.
This desirable ability springs from the 'polymer' in Li-poly. Instead of storing the lithium ions in organic solvents, the ions are held in a non-flammable polymer matrix. But there are more advantages than just the lack of explosions. Li-poly batteries do not require a metal
casing to squeeze the battery's electrodes together so they can be up to 20% lighter than Li-ion batteries. Also, the form-factor of Li-poly batteries is much more flexible than the necessarily boxy or cylindrical Li-ion cells, and they can be as thin as a credit card.
Of course, they come with their disadvantages too. Most important to the consumer market, they are more expensive and they lose capacity faster than Li-ion batteries. But in our eyes, potential environmental concerns are significant as well. Most Li-poly batteries on the market today require some fluoropolymers in the matrix. Fluoropolymers are expensive and difficult to create, requiring a lot of energy and chemicals. And, most troubling, there are currently no good programs in place to recycle lithium-polymer batteries.
As the technology is adopted, we can hope that less resource-intensive materials can be incorporated, that the technology will become cheaper, and that low-risk, inexpensive methods of recycling will be produced. Hopefully, these technological advances will occur quickly, because their increased safety, decreased weight and flexible form factor make them absolutely perfect for use in electric cars.
But, in the meantime, I don't suggest TreeHuggers become early adopters of this technology. They need to be disposed of more rapidly than Li-ion batteries, they can't be recycled, and they contain some truly dangerous and energy intensive chemicals. The new and safer (though lower energy-density) Li-ion batteries should suit the short-term needs of the techno-treehugger.
::Lithium Polymer at Wikipedia. See also: New Battery Design Charges in One Minute
Really, really important note here. They may not explode when punctured, but you definitely do NOT want to charge a damaged battery. The model aviation community discovered that aspect of the technology early on:
Crashed Plane + Damaged LiPoly Battery + Charging = Really Bad Fires
Fluoropolymers are expensive and difficult to create, requiring a lot of energy and chemicals.
Aren't Fluoropolymers used in some solar cell production also?
Li-ion batteries do much better at very cold temperatures than other batteries. So I got some for my bike light since I ride all winter.
we didn’t have the capability inside the company to get the products to market on time, much less designed correctly
“We went to each customer affected by the notebook situation and made it right.” page 53 Ibid docket 80 Addendum 5 “Here’s why you shouldn’t be nervous about doing business with us.” page 53 Ibid. docket 80 Addendum 5 “You’re not a customer for just one transaction. You’re a customer for life.” page 53 Ibid. docket 80 Addendum 5 “There’s no question about who’s accountable if there’s a product problem, and no question about who’s responsible for fixing it. Because of a direct model, we were able to contact our customers quickly and directly, and as a result, recover from the problem fast.” page 53 Ibid. docket 80 Addendum 5
“The notebook problem also illustrated how we utilize the direct model within the company.” page 53 Ibid. docket 80 Addendum 5 “One of the keys to dazzling and delivering on the Latitude was the lithium ion battery.” page 53 Ibid. docket 80 Addendum 5 “In January 1993, soon after we launched Dell in Japan, I met with the folks at Sony.” Page 53 Ibid. docket 80 Addendum 5
“… toward the end of the meeting, a young Japanese man ran up to me and said, “Mr. Dell, please wait one minute. I’m from the energy power systems group and I need to talk to you.” “Energy power systems?” I thought. “Is this guy going to try to sell me a power plant?” page 54 Ibid. docket 80 Addendum 5
“Still, I was intrigued, so I stayed and listened to what he had to say. He started showing me chart after chart describing the performance of a new battery technology called lithium ion. Suddenly I realized his goal: to sell lithium ion batteries to Dell for our notebooks.” page 54 Ibid. docket 80 Addendum 5 “If this was true, I wanted to put lithium ion batteries in every notebook computer we made.’ page 54 Ibid. docket 80 Addendum 5 “They had never built a battery with the cell size we wanted and the number of cells in a battery pack that we needed, and they saw notebooks as a tremendous opportunity to move into a new market.” page 54 Ibid. docket 80 Addendum 5 “Lithium ion became a breakthrough technology.” page 54, Ibid. docket 80 Addendum 5
“As easy a decision as this might seem, in retrospect, lithium ion was a brand new technology, and therefore a risk.” pages 54-55 Ibid (emphasis added) docket 80 Addendum 5
“And even though the people at Sony kept coming back with the right answers to our questions, no one really knew how lithium would hold up.“ page 55 Ibid. (emphasis added) docket 80 Addendum 5 “The Latitude with the lithium ion battery was introduced in August 1994.” page 55 Ibid. docket 80 Addendum 5
The book Direct from Dell Strategies That Revolutionized an Industry was provided to Defendants. Michael Dell was a listed expert The book Direct from Dell Strategies That Revolutionized an Industry docket 80 Addendum 5 , by Michael Dell Chairman and CEO, Dell Computer Corporation with Catherine Fredman, Copyright 1999 was provided to Defendants. Satisfying plaintiffs requirements regarding Michael Dell’s expert opinions as quoted above per Fed. R. Civ. P. 26(a)(2)(B). The book reviewed his qualifications and the gist of his opinion.
"but they can be banged around, punctured, "
I'd just like to say that they CAN NOT be punctured, as it will cause a fire. Do a search on youtube of people puncturing lipo batteries to see what I mean.