The electrification of society has been underway for yearsbut in recent times this has accelerated considerably. It is not only that the lighting network uses electricity or that household appliances leave aside other energy sources such as natural gas, but even cars are being transformed. And in the future this will increase, at least in the European Union, which has in renewable energies the ideal tool for improve the environment and reduce the continent’s dependence on petroleum products.
Many of these devices are used connected to the electrical network, such as smart speakers, televisions, refrigerators or washing machines, but many others depend on batteries because their use involves some movement. The best example is mobile phones, but also watches, tablets and cars.
Even some products rely on batteries to offer a different and more versatile experience. We have an example in the range of Xiaomi fans, which have one with battery so that it can be moved to different rooms and does not always have to be near a socket.
Elastic batteries
Current batteries are all based on the same metal basesometimes lithium, sometimes nickel, but they have a rigid structure that severely limits the shape of the devices in which they are used, as well as the possible applications. However, some research suggests that this is not the case. Solid-state batteries are one way forward for devices such as cars and large objects, but many other devices are going in the opposite direction, are small and require other batteries.
Researchers at the University of Cambridge have designed a new flexible and stretchable batteries that seek to be used in roboticsbut also in the design of body devices, both wearable and medical implants. These batteries are created with synthetic materials that resemble gelatin, with a layered structure that allows them to deliver electrical current, as eels do.
Gelatin batteries were made from hydrogelsthrough 3D polymer networks composed of more than 60% water, with off-on interactions that depend on the structure of the material itself. This is important because you can stretches up to 10 times its size without losing its properties, including elasticity and conductivitytwo characteristics that are very difficult to maintain simultaneously.
In this way, the rigidity of current batteries would no longer be an obstacle in the use of certain implanted devices in medical operations, or in other devices that require a rigid part of a certain volume, as is the case of smart watches, which must always house the battery and the more autonomy is sought, the larger they are.
“It is difficult to design a material that is stretchable and highly conductive because these two properties are usually opposite. Normally, conductivity decreases when a material is suffocated. said Stephen O-Neill, study author and member of the Yusuf Hamied Department of Chemistry at Cambridge.
“Hydrogels are made of polymers that have a neutral charge, but if we charge them, they can become conductive.” says co-author Dr Jade McCune, also of the Department of Chemistry.And by modifying the salt component of each gel, we can make them sticky and crush them into multiple layers, in order to accumulate greater energy potential.”
One of the biggest new features of these batteries is that They do not use electrons to transmit electricity
“We can tailor the mechanical properties of hydrogels to resemble human tissues,” said Professor Oren Scherman, director of Melville’s Polymer Synthesis Laboratory, who led the research.“Because they do not contain rigid components such as metal, a hydrogel implant would be much less likely to be rejected by the body.”
These hydrogels are soft and not at all rigid, but they are also very resistantsomething that may seem contradictory but is real. They exhibit high resistance to deformation without losing the function of returning to their original shape without damage. Medical applications are the first expected uses of this type of battery but, as is the case for military developments, It is likely that if it comes to fruition, it will eventually enter the private sector. and we end up seeing a multitude of devices, especially small ones, with this type of battery.