In a scenario where advances in the electrification of the automobile industry and the use of renewable energies, lithium has become the main protagonist, receiving most of the attention of R&D programs. However, it is a technology that, although it still has a way to go, especially for improve thermal performance and mitigate its degradation, is already in its final phase to extract potential from it. In addition to lithium, range of materials and systems used to store and supply energy as needed is much broader than one might suspect: a sample is in the 10 examples that we expose below.
In this list appear batteries that can function as a source of energy for an electric vehicle, and also those that can power small electronic devices or electrical networks the size of a city. The solutions being developed are broad: they include batteries based on sand, carbon dioxide, heat and water and others that may be even more surprising.
A Finnish startup called Polar Night Energy is heating buildings in the city of Kankaanpää with a battery that it developed from sand. The battery is in the form of a tower containing 100 tons of sand. The sand is superheated to around 500°C using renewable energy. Wind power is used in general, and solar power is particularly used in summer. The sand retains its heat for about three months for use in the long, cold winter.
A team of researchers at the Rensselaer Polytechnic Institute in Troy, New York, proposes the calcium ions as a greener, more efficient and less expensive energy storage alternative to lithium ions. “We are working on an inexpensive, abundant, safe, and sustainable battery chemistry that uses calcium ions in a water-based, aqueous electrolyte,” explains Rensselaer engineering professor Nikhil Koratkar in a press release.
Although the larger size and higher charge density of calcium ions relative to lithium impair diffusion kinetics and cyclic stability, Koratkar and his team offer oxide structures that contain large open spaces (heptagonal and hexagonal channels). ) as a possible solution.
Being the divalent calcium ion, it will deliver two electrons per ion during battery operation. This allows a high efficiency with low mass and volume of calcium ions. However, its higher ionic charge and larger size relative to lithium make it very difficult to insert calcium ions into battery electrodes. To overcome that problem, Koratkar explains the development of a special class of materials called molybdenum and vanadium oxides that contain large hexagonal and heptagonal channels or tunnels running through the material.
carbon dioxide batteries
A company called Energy Dome has completed a pilot test installation on the Italian island of Sardinia. Its carbon dioxide battery can store the energy needed to service an electrical grid for 10 hours at less than half the cost of a lithium-ion battery system.
The COtwo it has the property of condensing and being stored as a liquid under pressure and at room temperature. The ‘loading’ process consists of taking the COtwo stored in a large vault at atmospheric temperature and pressure, and compressed into a liquid using renewable energy sources such as wind and solar. The result generates heat that warms the COtwo liquid to be converted into gas which passes through a turbine and generates electricity in the ‘unloading’ process. The COtwo it returns to the dome where it remains for the next charge cycle.
The Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have developed a thermophotovoltaic (TPV) cell that converts heat into electricity by passively capturing high-energy photons from a heat source. With an efficiency greater than 40%, its performance is better than that of traditional steam engines, according to MIT.
According to the MIT News Bureau, the plan is to incorporate the TPV cell into a grid-scale thermal battery, such that the system would absorb excess energy from renewable sources like the sun and store that energy in banks of hot, strongly heated graphite. isolated. When power is needed, such as on cloudy days, the TPV cells would convert the heat into electricity and send the power to a power grid.
Alsym Energy is working on a battery that does not use nickel, cobalt, or lithium in the cathode, but instead uses manganese oxide, while the anode is an oxide of a metal other than lithium. As the company explains, by eliminating them, it avoids the problems associated with the supply and costs of each of these materials. The electrolyte consists mainly of water and does not require the use of organic solvents. Non-flammable and non-toxic materials make this battery more environmentally friendly and safer as there is no risk of ignition and burning.
Batteries are being developed for electric vehicles and other applications. Alsym has convinced Singapore-based ship management service provider Synergy Marine to work together developing specific applications for the shipping industry. Alsym will provide Synergy and Nissen Kaiun with “one gigawatt of batteries per year for three years. Battery systems must meet key performance levels and specific regulatory requirements for cargo ships and oil tankers.”
Another “water battery”
The largest example of a water battery we have to date is the “Nant de Drance battery” in Valais, Switzerland. Its components are the Vieux Emosson reservoir, which contains 25 million cubic meters of water (more than 6,500 Olympic swimming pools), and the Emosson reservoir downstream of the first, the second largest reservoir in Switzerland, a cavern 600 meters deep .
Between the two reservoirs there are six water turbines, each capable of generating 150 MW of electricity. Renewable energy, when plentiful, drives turbines to pump water from the lower to the upper reservoir; when necessary, the water is returned to the lower reservoir through the turbines to generate electricity. According to Nant de Drance, the energy storage capacity of this giant battery is 20 million kWh, equivalent to that of 400,000 electric car batteries.
Dutch heavy-duty equipment developer Huisman Manufacturing is working with Graviticity, a start-up based in Edenburgh, Scotland, to make gravity battery systems. The concept consists of a tower or a mine shaft on which a heavy weight is suspended. As with the sand and water based examples mentioned above, renewable energy is used to power winches to lift the weight; when power is needed, the weight is allowed to gradually descend, generating electricity in the process.
Stora Ensoa manufacturer of paper and renewable construction and packaging products, is working with northvolt to develop wood-based batteries equipped with an anode produced with hard carbon based on lignin, a component produced and extracted from the wood of trees.
Stora Enso owns the patent and the different methods of using lignin, which they commercially call Lignode. The company has the key components and the experience with which they aspire to make this project possible. This company obtains the necessary material through the exploitation of its own forests managed in a sustainable way. From Northvolt they will be in charge of promoting the design of the cells, the development of the production process and the possible expansion of this technology.
Paper and water battery
Materials science and technology developer Empa has developed a water-activated disposable paper battery. The researchers suggest it could be used to power a wide range of low-power, single-use disposable electronic devices, such as smart tags for tracking objects, environmental sensors, and medical diagnostic devices.
the startup Group1based in Austin, Texas, claims to be the first company in the world to commercialize cathode materials for new potassium ion batteries (KIB). In a press release, the company stated that it uses a “machine learning-driven process to optimize its production of fast-charging, high-efficiency, and safer KIB potassium Prussian white (KPW) cathode materials, which can be An alternative to lithium ion batteries.
The company argues that industry adoption of Group1’s KPW cathode materials “will accelerate due to the alignment of its existing graphite anode materials, electrolytes, cell design and battery manufacturing processes.” lithium ions. This means manufacturers do not need to change existing infrastructure.”
The potassium used in Group1’s KPW cathode materials is 1,000 times more abundant on earth than lithium and 20 times more affordable, according to Group1.