Electrochemical Performance of Na2FeP2O7 for Aqueous Sodium-ion Batteries
Creators: name: Nestrova, Inara
name: Kucinkis, Gints
name: Erts, Donats
Publisher: name: Zenodo
Year: 2024
Subjects: subject: Electric energy
subject: Renewable energy
subject: energy harvesting
subject: sustainable materials
subject: waste heat
subject: h2020
subject: EU Funded
subject: Heat engineering
subject: waste heat recovery
subject: waste heat to electricity
subject: batteries
subject: Electrochemistry
subject: electrochemistry
subject: Na-ion
subject: energy density
subject: energy storage
subject: sodium insertion material
subject: electrolytes
subject: non-aqueous electrolyte
subject: aqueous electrolyte
subject: Cells technologies
subject: half cells
subject: symmetrical cells
subject: gravimetric capacity
subject: battery cell architecture
subject: electrochemical performance
subject: Nano-materials
subject: Combined heat and power
subject: Energy conversion
subject: Energy and fuels
subject: Bulk nanostructured materials
subject: Materials engineering
subject: FOS: Materials engineering
subject: cathode materials

description: Abstract:

Sodium-ion batteries are already widely researched and developed as a more environmentally friendly and cheaper alternative to lithium-ion batteries. In parallel, opportunities are being sought to improve and optimize the performance of the overall battery, developing more environmentally friendly electrolytes. As a promising alternative, sodium-ion batteries are being studied with a water-based electrolyte. Aqueous electrolytes are much safer, with a lower cost and non-flammable compared to commonly used toxic organic compounds.

Na2FeP2O7 is one of the most stable cathode materials for sodium-ion batteries. In the organic electrochemical cell, it shows high cyclability and good rate capability, charge capacity can be obtained close to the theoretical (97 mAh/g).  Moreover, it is very stable in water thus making it an attractive cathode for aqueous sodium-ion batteries. 

In this work Na2FeP2O7 was tested in aqueous electrolyte in half-cells and symmetrical configuration. X-ray diffractometry shows no significant changes after treating the raw material (powder) with water. Cyclic voltammetry shows characteristic Na2FeP2O7 peaks. Although the obtained charge capacity using aqueous electrolyte is lower than using organic electrolyte, stable cyclability is obtained in a symmetrical cell. Na2FeP2O7 reaches up to 60 mAh/g (62% of theoretical specific capacity 97 mAh/g). 

In summary, electrochemical properties of Na2FeP2O7 in an aqueous electrolyte were investigated and characterized for the further use of the material for aqueous sodium-ion batteries. 

The financial support of Horizon 2020 FETOpen project TRANSLATE (ID 964251) is greatly acknowledged.
description: This presentation was delivered by PhD student Inara Nestrova at the 37th Topical Meeting of the International Society of Electrochemistry. This was held in Stresa, Italy, between June 9-12, 2024.

TRANSLATE is a €3.4 million EU-funded research project that aims to develop a new nanofluidic platform technology to effectively convert waste heat to electricity. This technology has the potential to improve the energy efficiency of many devices and systems, and provide a radically new zero-emission power source. The TRANSLATE project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 964251, for the action of 'The Recycling of waste heat through the Application of Nanofluidic ChannelS: Advances in the Conversion of Thermal to Electrical energy'. More information can be be found on the TRANSLATE project website: https://translate-energy.eu/