Lithium-ion batteries are used in all the gadgets that surround us, and in the forthcoming electric cars. New versions of them are on their way, and one month after another brings news about new emerging technologies.
For example, Seeo, Inc, from California, is ready to manufacture a new type of lithium ion battery. Classic batteries are made from lithium cobalt oxide electrodes and a liquid electrolyte, usually lithium salts dissolved in an organic solvent. They are sealed hermetically and have the bad property of catching fire and exploding if overcharged, because the charged electrodes are very reactive with the liquid electrolyte, fact that also reduces their power and life cycle.
Seeo’s batteries don’t use liquid a electrolyte, but instead, a solid polymer. Mohit Singh, the co-founder of Seeo, says “Lifetime data suggests that conventional lithium-ion systems lose about 40 percent capacity in 500 cycles. We get a much better cycle life. We can go through 1,000 cycles with less than 5 percent capacity loss.”
That’s pretty cool. Keep into account that these batteries aren’t in the risk of explosion, and can be stored inside heat-sealed pouches. They also have a great energy density, of about 300 watt-hours per kilogram, which is 50% more than current Li-Ions can store.
Seeo’s technology “has become very attractive” because of its claim of a high-conductivity polymer, Khalil Amine, manager of the advanced battery technology group at Argonne National Laboratory, says. However, “the lithium anode could be a show-stopper.” Lithium has a tendency to get roughened at the surface and grow crystal dendrites that can reach the cathode and short the battery. The company will need to do long-term tests to show that its polymer is hard enough to block the dendrites.
The bad news is that these batteries miss something important: they don’t charge as fast as liquid-based li-ions, so their usage would be limited to inexpensive electric cars and laptops. Skipping that, the energy density would make them perfect candidates for some electric car, since they can store more in the same space, so you wouldn’t have to charge your car two times if you’re on a 500 miles trip, for example.
