The future of batteries
Moore’s Law tell us to expect that the ability of a microprocessor to double every 18 months has even been applied similarly to the storage capacity and even the bandwidth every time we have electronic products faster, smaller and more memory. But Batteries that use these products are based on a technology with over 20 years old and improvements have come at a glacial pace. But there are hopeful signs that this is soon to change.
For starters, the battery problem is more of an edge. First we have the capacity problem. The batteries capable of storing more energy in the same space and hopefully in increasingly smaller sizes, in other words, we want more watt-hours per kilogram (Wh/kg). We also want to reach their maximum load in the shortest time possible. Then we want the batteries becomes cheaper to make, for example, electric cars or hybrids can cost the same or less than gasoline cars. Additionally, all batteries have a limited life because with each cycle of loading / unloading it loses capacity. And finally we have the thermal problems where the batteries heat up after use, to even create safety problems with batteries entering into combustion. What we need today are cheap batteries, secure and loaded to capacity within minutes, to endure thousands of cycles of charge and with a density required to build a lot of energy in the smallest space possible.
The batteries of today
The most popular and advanced batteries that are today in our artifacts are the batteries of Lithium-Ion Polymer – something that is very happy to Argentina , Bolivia and Chile , as these three countries account for its salt mines in the 90% of the world’s Lithium . These we can find today in our electronic devices, electric cars and even the power supply system. However, the Li-Ion batteries began shipping in 1991, so we have been using almost the same technology for over two decades and on which we can all agree that an update is needed urgently.
These batteries we use today have a lifespan of 400 to 1200 charge cycles, and a capacity of 100 to 250 Wh/kg. Finally, we have the problem of loading speed where, for example, to an iPod in the first 2 hours, 80% load capacity, then it takes 2 hours to load the remaining 20%.
Accentuated problem especially when applied in electric automobiles. Last year I was driving for a couple of weeks a Mitsubishi iMiEV and though the path I walk every day is not more than 15 km, but I had to charge the Li-Ion battery every 3 days. At the point of recharge it could recharge to 50% capacity in 15 minutes and then had to pass to a charging cycle much slower than 8 hours and lasted until “significantly degrade” the capacity of the battery, shortening its life quickly, if it is continued with fast charging. It will be difficult to convince the world to switch to electric cars while the batteries charge so slow, they are so expensive and must be replaced over a few years.
The batteries of tomorrow
The disadvantages of current technology are clear, and we begin to see that there is hope in the future. There are four technologies that look promising: Silicon Lithium-Ion, Lithium-Ion 3D, Lithium-Zinc-air and air.
Several researchers, including the team of Dr. Yi Cui at Stanford University have announced progress in replacing the anode in a Li-Ion covered by a silicon nanowires instead of graphite (carbon) used today. The result is Li-Ion battery with a specific capacity 10 times greater than current batteries. Traditionally the problem of silicon anodes during charging was that these could increase up to 4 times its size, and then returns to its original dimensions during unloading. This means that after a few cycles of loading, the anode was destroyed resulting in a very short lifespan for the battery. But recent advances in silicon nanotubes are dual layer, hope that finally this obstacle has been overcomed with laboratory demonstrations on the 6000 charge cycles, considerably exceeding the lifetime of current batteries. This would provide batteries with a capacity of 10 times using the same space, and a life 6 to 12 times higher than today.
The company Prieto Battery and its founder Dr. Amy Prieto (no relation), are working on another way to replace the graphite anode in a Li-Ion battery with something more efficient. In his case the anodes are replaced with copper nanowire. The results are batteries work in “3 dimensions”, allowing movement of ions much faster, with one benefit being able to charge the battery at 100% of an iPhone in 5 minutes with a power source of 240 volts. To this we must add the benefit of safer batteries and a theoretical lifetime of over 5,000 charge cycles.
Both IBM and PolyPlus , among others, are investigating the Lithium-air where atmospheric oxygen used to change the traditional structure of the cathode. This results in a specific capacity battery with 10 times the current (which would be similar to the energy density of gasoline in a car), considerably cheaper and additionally with reduced weight. Targeting primarily the automotive sector, promising a range over 800 km with a configuration similar to the current electric cars. However there is still the challenge of increasing battery life and solve the problems of contamination and moisture present in atmospheric oxygen, for which there are already several theoretical solutions with which they are experimenting.
Similar to lithium-air batteries rechargeable Zinc-air have long been only a promise. But eventually companies like EOS Energy Storage in the U.S. and ReVolt in Switzerland have exceeded promise, at least in the laboratory, its main deficiencies includes recharging efficiently. The batteries promises much cheaper, safer and with a lifespan of over 10,000 cycles of loading (at least in the case of EOS). It’s intention is to solve problems of energy storage in the electricity supply system, allowing you to capture the intermittent power obtained from wind turbines and solar panels, eliminating the main problems, these critics claim from renewable energy. Although ReVolt promises to have discovered how to use these batteries also in cars and electronic devices.
No matter which of these four technologies eventually leave the lab to actual use, the advances are promising. Experts agree that the ultimate challenge to overcome is the massive scale manufacturing of these technologies. At least governments and private investors are contributing large amounts to finally give a big leap in the evolution of the batteries. Best of all is that several of these companies plan to have these solutions in the market over a period ranging between 2013 and 2015. Cross your fingers!Tags: Amy Prieto, Argentina, Batteries, battery, Bolivia, Chile, IBM, Lithium, Lithium ion, Lithium-air, Lithium-ion 3d, Lithium-ion silicon, NanobaterÃas, PolyPlus, Prieto Battery, ReVolt, Stanford University, Yi Cui, Zinc air