Calcium‐Ion Batteries: Current State‐of‐the‐Art and Future Perspectives

Abstract

Recent developments in rechargeable battery technology have seen a shift from the well-established Li-ion technology to new chemistries to achieve the high energy density required for extended range electric vehicles and other portable applications, as well as low-cost alternatives for stationary storage. These chemistries include Li-air, Li-S, and multivalent ion technologies including Mg , Zn , Ca , and Al . While Mg battery systems have been increasingly investigated in the last few years, Ca technology has only recently been recognized as a viable option. In this first comprehensive review of Ca ion technology, the use of Ca metal anodes, alternative alloy anodes, electrolytes suitable for this system, and cathode material development are discussed. The advantages and disadvantages of Ca ion batteries including prospective achievable energy density, cost reduction due to high natural abundance, low ion mobility, the effect of ion size, and the need for elevated temperature operation are reviewed. The use of density functional theory modeling to predict the properties of Ca-ion battery materials is discussed and the extent to which this approach is successful in directing research into areas of promise is evaluated. To conclude, a summary of recent achievements is presented and areas for future research efforts evaluated.

A Calcium‐Ion Hybrid Energy Storage Device with High Capacity and Long Cycling Life under Room Temperature

“…[4] Moreover, the medium discharge voltage remained stable with negligible decay for 1000 cycles and only showed a slight decrease at high current density (Figure 3c). [4] Moreover, the medium discharge voltage remained stable with negligible decay for 1000 cycles and only showed a slight decrease at high current density (Figure 3c).…”

Graphite as a Long‐Life Ca2+‐Intercalation Anode and its Implementation for Rocking‐Chair Type Calcium‐Ion Batteries

“…In the quest for the next generation rechargeable batteries, divalent-ion batteries (Mg 2+ and Ca 2+ ) that could operate under the same principles as the current market leaders, lithium-ion batteries (LIBs), would be advantageous in several aspects. [1] Among them, the utmost merit would be that divalent ions are less prone to a dendritic growth during plating, which increases the chances for the implementation of metallic anodes and the fabrication of high-capacity batteries (2205 and 1337 mAh g −1 for Mg and Ca, respectively). Although there are some report on the dendrite growth in a divalent system, [2] the possible absence of dendrites also can significantly reduce the level of safety concerns, which would simplify both the cell configuration and the ancillary circuits.…”

Discovery of Calcium‐Metal Alloy Anodes for Reversible Ca‐Ion Batteries

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techniques with high energy density and low cost. [7,8] (2) Ca is the fifth most abundant element in the earth's crust with an extensive global resource distribution, in contrast to lithium. Among them, Ca-ion batteries (CIB) have drawn special attention with merits besides the capacity enhancement:

(1) Ca/Ca 2+ has a reduction potential (−2.87 V) only slightly higher than Li/Li + (−3.04 V), yet much lower than Mg/Mg 2+ (−2.36 V) and Al/Al 3+ (−1.68 V), which provides CIB the prospect to function at voltages comparable with Li-ion batteries and much higher than the counterparts of Mg-ion and Al-ion batteries.

…”

“…[7,8] (2) Ca is the fifth most abundant element in the earth's crust with an extensive global resource distribution, in contrast to lithium. [7,8] (2) Ca is the fifth most abundant element in the earth's crust with an extensive global resource distribution, in contrast to lithium.…”