Elon Musk is the man who wants to conquer space, travel from Los Angeles to San Francisco in 35 minutes thanks to a transport system of vacuum tubes, and fill the roads only with electric self-driving cars. In addition, the founder of PayPal, Tesla and SpaceX has another great obsession: batteries. He has recently bought a power plant that can, thanks to the combination of rechargeable lithium ion batteries with solar energy, provide energy to 15,000 homes for four hours. Tesla, because of the interest it has for its electric cars, leads the shift towards this new type of battery, but this is not the only company focused on the same search. In a permanently connected world, batteries have become the great obsession of the technology firms, all of them seeking the battery of the future, one that is more powerful, more durable and safer.
In September 2016, in Florida, a Samsung Galaxy Note 7 exploded and burned the car in which it was being charged. Less than a month later, a flight from Louisville to Baltimore had to be diverted because a mobile phone of the same model began to emit smoke. By then there were already dozens of cases of these phones catching fire and the South Korean company had stopped production. Samsung had to remove it from the market and return the money or provide another phone to more than two million people. Today we know that these explosions were caused by faulty battery design.
Samsung’s nightmare illustrates the shared challenge—continuously reducing battery size, while at the same time giving them more capacity, creates great risks. For this reason there are already companies that have demonstrated the concept of “thinking outside the box” when facing this problem, and have changed the direction of their efforts. Nowadays, the near future of batteries is not that they last longer, but that they can be charged much faster. The objective is to achieve hours of use with just a few minutes of charging.
Companies and universities in search of the golden battery
Qualcomm, the company that manufactures the ‘brains’ of a large number of devices, is betting on this idea. Its Quick Charge 4.0 charging system is theoretically 20% faster and 30% more efficient, so that in just 15 minutes it can charge 50% of a 2,750mAh (milliampere hours) battery, the capacity of a normal mobile. At the same time, Samsung and Huawei have developed ‘Fast Charge’ and ‘Supercharge’, respectively, for the same purpose.
Scientists from numerous universities have also begun to participate in this search for the golden battery. Researchers at the University of Bath in the United Kingdom and the University of Illinois at Chicago have discovered that adding positively charged metal ions, such as potassium, makes the lithium (of which the vast majority of current batteries are made) move faster within the battery structure. This causes the batteries to charge much faster, as they have published in the scientific journal Nature Communications.
Meanwhile, a group of researchers from the University of Central Florida have developed flexible supercapacitors that can be recharged more than 30,000 times without degrading and that charge in just seconds. “If you were to replace the batteries with these supercapacitors, you could charge your mobile phone in a few seconds and you wouldn’t need to charge it again for over a week,” said Nitin Choudhary, the postdoctoral associate leading the research. Although this is a technological advance, it does have one main drawback: size. Thus, the new objective of the project managers is to try to reduce the size of the supercapacitors in order to be able to integrate them into small devices such as mobile phones.
The fight against degradation
Another major problem with today’s lithium-ion batteries is that our repeated charging of them, especially in mobile phones, causes them to degrade very quickly and begin to lose some of their effectiveness after about a year of use. The life of these batteries is approximately 1000 complete cycles of charging and recharging, and at the moment no possibility of extending this has been found.
Until now, that is. Harvard scientists have created a new type, called a flow battery, which could last for more than a decade without degrading. Their new method is to store the energy in liquid solutions. The trick is to modify the molecules of the electrolytes (ferrocene and viologen) so that they become stable, water soluble and resistant to degradation. The researchers say that by dissolving these molecules in neutral pH water, the batteries will only lose 1% of their capacity for every 1,000 cycles. In addition, they are “considerably safer” since this solution does not contain corrosive or toxic elements. However, at the moment they cannot be used in mobile phones, as these cannot contain water, so it is not known when they can be considered to be a real option. It seems that the super battery of the future is still in the laboratory.