Recent Progress in Multivalent Metal (Mg, Zn, Ca, and Al) and Metal‐Ion Rechargeable Batteries with Organic Materials as Promising Electrodes

Abstract

The emerging demand for electronic and transportation technologies has driven the development of rechargeable batteries with enhanced capacity storage. Especially, multivalent metal (Mg, Zn, Ca, and Al) and metal‐ion batteries have recently attracted considerable interests as promising substitutes for future large‐scale energy storage devices, due to their natural abundance and multielectron redox capability. These metals are compatible with nonflammable aqueous electrolytes and are less reactive when exposed in ambient atmosphere as compared with Li metals, hence enabling potential safer battery systems. Luckily, green and sustainable organic compounds could be designed and tailored as universal host materials to accommodate multivalent metal ions. Considering these advantages, effective approaches toward achieving organic multivalent metal and metal‐ion rechargeable batteries are highlighted in this Review. Moreover, organic structures, cell configurations, and key relevant electrochemical parameters are presented. Hopefully, this Review will provide a fundamental guidance for future development of organic‐based multivalent metal and metal‐ion rechargeable batteries.

Recent progress in graphene‐based electrodes for flexible batteries

“…Flexible multivalent metal‐ion (such as Zn and Al‐ion) batteries are promising due to the abundance and low cost of multivalent metals. In particular, zinc‐ion batteries (ZIBs) have attracted extensive attentions with their advantages of two‐electron redox, high safety, and easiness to scale up . NaV 3 O 8 ∙1.5H 2 O (NVO) is a prevailing cathode material in ZIBs but the reported capacity has been far less than its theoretical capacity (486 mAh g −1 ) owing to the poor conductivity of NVO.…”

Cross‐Conjugated Polycatechol Organic Cathode for Aqueous Zinc‐Ion Storage

“…The versatility of organic materials allows them to play important roles in rechargeable zinc‐ion batteries, such as energy storage and chemical protection . Among organic electrodes, carbonyl compounds are commonly used, in which the C=O bond can coordinate reversibly with the metal ion . However, carbonyl compounds may dissolve in most organic electrolytes more or less during discharge–charge .…”

“…[7] Among organic electrodes, carbonyl compounds are commonly used, in which the C=Ob ond can coordinate reversibly with the metal ion. [8] However,c arbonyl compounds may dissolve in most organic electrolytes more or less during discharge-charge. [9] Although some organice lectrode materials such as p-chloranil,c alyx-4-quinone, and pyrene-4,5,9,10-tetraone have been proposed for aqueous zinc-ion storage, [10] some challenges for these options still remain, for example, the intrinsic low conductivity and the rapid capacity decay.…”

Redox Polymers as Electrode-Active Materials for Batteries

“…4,10,11 Sodium 2,7,12,13 as well as multivalent metals, such as magnesium, zinc and aluminum, have also been used. 14 If the polymer is of p-type, such metal-organic cells operate in a dual-ion mode, where both electrolyte cations and anions are required for charge balancing in the anode and cathode, respectively. 15,16 With an n-type polymer, only metal cations are needed, resulting in a cation rocking-chair battery.…”