We are familiar with various technologies from batteries as power storage. The cheapest and therefore most common are lead-based batteries. We are all familiar with lead-acid batteries or lead-gel batteries from car batteries, which is why this technology is also used for storing electricity.
However, many suppliers now rely on lithium-ion technology, which can withstand more charging and discharging cycles than lead-acid batteries. Further advantages are the very low memory effect, if any, and the high energy density, as well as the thermal stability, the constant voltage during the entire discharge process and the very low self-discharge. The disadvantage of this technology are safety measures that increase the costs for these batteries (source: Stromtankstellen.eu). A lot is expected of lithium-ion batteries in the future, both in the storage of renewable energies and in electromobility. But especially falling prices are expected, which are important for a growing market. Lithium-ion battery storage is available in various sizes from 2 kWh to the megawatt range, as the Younicos storage systems show.
Battery alternative salt-nickel
Another alternative are sodium nickel chloride (SoNick) accumulators. These are high-temperature batteries that require temperatures between 300° and 400° Celsius and, according to Wikipedia, consist of a solid electrolyte and a combination of liquid and solid electrodes. Thanks to their modular design, these storage units are scalable for all application sizes and can be supplied from 4 kWh to 1.5 MWh. The SoNick technology solves the recycling problem posed by other technologies, the components of the SoNick batteries are completely recyclable.
The Italian market leader FIAMM, otherwise known for car horns, is now using this technology to address the growing market for energy storage and holistic solutions for intelligently feeding electricity into the respective consumption grid.
“The 100 percent ecological salt batteries from the FIAMM Group are the ideal storage medium for this,” explains Stefano Dolcetta, Managing Director of FIAMM SpA. The high cycle stability ensures a superior service life of 15 years. After that, all components can be easily recycled. In addition, the SoNick batteries are around 70 percent lighter than conventional lead-acid batteries and around 30 percent smaller with the same performance. That’s why they take up less space and fit in two standard 20-foot ISO containers.”
Another advantage of this technology is the constant power output, even at extremely different temperatures of minus 20 and plus 60 degrees Celsius. This means that they are always quickly ready for use, which is not the case with other technologies such as lead-acid batteries, which are sensitive to extreme heat or cold. An air conditioning system is therefore not required with this technology, which significantly reduces costs and energy requirements. Furthermore, the batteries from FIAMM are maintenance-free and can be controlled remotely with the integrated electronic control.
With a discharge of up to 80% of the storage capacity, the battery can be charged up to approx. 4,500 times.
Efficient storage for off-grid use with photovoltaics
The off-grid solution of a five-star hotel complex in the Maldives is an interesting example of battery use. The “Gasfinolhu Island Resort” on the approximately two-hectare small island of Gasfinolhu in the North Male Atoll will in future cover its energy requirements almost entirely with the help of photovoltaic solar cells. The Italian battery specialist FIAMM makes a significant contribution to the storage and needs-based feeding of the green electricity into the microgrid of the island:
The FIAMM “Microgrid Hybrid Energy System ST523” collects the solar power in highly innovative sodium-nickel chloride batteries and supplies up to 1.5 megawatt hours (MWh) of electricity when required, for example at night or at times of heavy cloud cover. The supply is thus always reliably secured. A wealth of other measures further improves energy efficiency and makes the new plant a showcase project worldwide.