Sodium-Based Batteries: In Search of the Best Compromise Between Sustainability and Maximization of Electric Performance

Abstract

Till 2020 the predominant key success factors of battery development have been overwhelmingly energy density, power density, lifetime, safety, and costs per kWh. That is why there is a high expectation on energy storage systems such as lithium-air (Li-O2) and lithium-sulfur (Li-S) systems, especially for mobile applications. These systems have high theoretical specific energy densities compared to conventional Li-ion systems. If the challenges such as practical implementation, low energy efficiency, and cycle life are handled, these systems could provide an interesting energy source for EVs. However, various raw materials are increasingly under critical discussion. Though only 3 wt% of metallic lithium is present in a modern Li-ion cell, absolute high amounts of lithium demand will rise due to the fast-growing market for traction and stationary batteries. Moreover, many lithium sources are not available without compromising environmental aspects. Therefore, there is a growing focus on alternative technologies such as Na-ion and Zn-ion batteries. On a view of Na-ion batteries, especially the combination with carbons derived from food waste as negative electrodes may generate a promising overall cost structure, though energy densities are not as favorable as for Li-ion batteries. Within the scope of this work, the future potential of sodium-based batteries will be discussed in view of sustainability and abundance vs. maximization of electric performance. The major directions of cathode materials development are reviewed and the tendency towards designing high-performance systems is discussed. This paper provides an outlook on the potential of sodium-based batteries in the future battery market of mobile and stationary applications.

Ionic and Thermal Transport in Na-Ion-Conducting Ceramic Electrolytes

“…Furthermore, due to the expected increasing number of Li-ion cells for the growing market of electrical vehicles and stationary storage for intermittent renewable energy sources, limited Lithium resources and higher costs may call for alternative elements in future decades. A promising alternative at least for stationary storage could be Sodium [6,7], which is cost effective without the limitation in the Li resources and exhibits comparable physicochemical and electrochemical properties.…”

Reviewing the Safe Shipping of Lithium-Ion and Sodium-Ion Cells: A Materials Chemistry Perspective

“…(2) In conducting the above studies, particular emphasis should be put on the effect of the electrolyte as it is known that there is an intimate relationship between the safety of a Li-ion cell and the electrolyte it contains [6,12]. Some recent results on large-scale Na-ion cells indicate that Na-ion electrolytes utilising high weight fractions of thermally stable solvents such as PC or Tetraglyme can indeed result in lower rates of heat generation or higher thresholds for onset of exothermic self-heating reactions [65][66][67][68] (3) Recently, some articles have analysed the economic potential of Na-ion batteries from a materials perspective [19][20][21]. Detailed life-cycle cost estimations for Na-ion batteries, focussing on not just material costs or resource availability, but other factors such as costs of shipping/storing Na-ion cells at 0 V, relative to Li-ion cells at 30% SOC, and also their recycling, would certainly be timely and illuminating for the alkali-ion battery community…”

“…, as Al is not only much lighter than Cu but also cheaper[14,[19][20][21]. Unfortunately, Li alloys with Al to form Li x Al at low potentials vs. Li/Li + , thus requiring the need for Cu on the anode, as Li does not diffuse into Cu in appreciable quantities during normal operation of a rechargeable Liion cell…”

The Unusual Conductivity of Na+ in PEO‐Based Statistical Copolymer Solid Electrolytes: When Less Means More

“…The development of solid‐state sodium batteries (SSNaB) is driven by the need to address the ineluctable depletion of lithium resources that will follow the massive deployment of Li batteries for renewable energy storage [1–3] . Both Li + and Na + are isoelectronic, and have similar properties, [4, 5] but Na + is remarkably more abundant, making sodium much cheaper than lithium [6, 7] …”

“…[1][2][3] Both Li + and Na + are isoelectronic,and have similar properties, [4,5] but Na + is remarkably more abundant, making sodium much cheaper than lithium. [6,7] Solid polymer electrolytes (SPE) are polymers that can dissolve ionic species and allow ionic conductivity.P oly(ethylene oxide) (PEO) is the archetypal SPE for Li + .T he coordination of the Li + cation by the oxygen atoms of the polymer imparts solubility and separation from the counter anion. However,too strong acoordination leads to adecrease in cation mobility and transference number, both of which are detrimental to the stable operation of abattery.…”