Advanced High Energy Density Secondary Batteries with Multi‐Electron Reaction Materials

Abstract

Secondary batteries have become important for smart grid and electric vehicle applications, and massive effort has been dedicated to optimizing the current generation and improving their energy density. Multi‐electron chemistry has paved a new path for the breaking of the barriers that exist in traditional battery research and applications, and provided new ideas for developing new battery systems that meet energy density requirements. An in‐depth understanding of multi‐electron chemistries in terms of the charge transfer mechanisms occuring during their electrochemical processes is necessary and urgent for the modification of secondary battery materials and development of secondary battery systems. In this Review, multi‐electron chemistry for high energy density electrode materials and the corresponding secondary battery systems are discussed. Specifically, four battery systems based on multi‐electron reactions are classified in this review: lithium‐ and sodium‐ion batteries based on monovalent cations; rechargeable batteries based on the insertion of polyvalent cations beyond those of alkali metals; metal–air batteries, and Li–S batteries. It is noted that challenges still exist in the development of multi‐electron chemistries that must be overcome to meet the energy density requirements of different battery systems, and much effort has more effort to be devoted to this.

Recent Progress in Iron‐Based Electrode Materials for Grid‐Scale Sodium‐Ion Batteries

“…The conductivity of the electrode materials, conversion energy gap, and drastic volume expansion show large effects on the performance of the electrodes. Thus, strategies such as structural modification, nanoscaling, and conductive materials decoration have been proposed as ways to facilitate the reverse extraction of Na + from the NaX n , to mitigate the pulverization and to enhance the performance of these electrodes …”

Fabrication of ultrafine Gd2O3nanoparticles/carbon aerogel composite as immobilization host for cathode for lithium‐sulfur batteries

“…Currently, lithium intercalation electrochemistry‐based rechargeable lithium‐ion batteries nearly reach their theoretical capacity . But they still cannot satisfy the urgent requirements for emerging technology, such as large‐scale energy storage and electric vehicles (EVs) . Because of the ultrahigh theoretical capacity (1675 mAh g −1 ) and theoretical energy density (2600 Wh kg −1 ) of sulfur cathode materials, lithium‐sulfur (Li‐S) batteries have drawn considerable attention with the assistance of abundance in nature and environment‐friendliness of S …”

“…2 But they still cannot satisfy the urgent requirements for emerging technology, such as largescale energy storage and electric vehicles (EVs). 3 Because of the ultrahigh theoretical capacity (1675 mAh g −1 ) and theoretical energy density (2600 Wh kg −1 ) of sulfur cathode materials, lithium-sulfur (Li-S) batteries have drawn considerable attention with the assistance of abundance in nature and environment-friendliness of S. 4,5 Despite these advantages of S cathodes, some drawbacks still hinder the practical application of Li-S batteries, such as (a) the poor electrical insulation of S (5 × 10 −30 S cm −1 at 25°C) and corresponding sulfides during cycling 6,7 ; (b) the noticeable volume changes (80%) of S cathode during the cycling 8 ; and (c) the dissolution of intermediates, as known, polysulfide (Li 2 S x , 4 ≤ x ≤ 8), 9 which would shuttle between two electrodes, leading to severe capacity fading and the deterioration of electrochemical performance. 10,11 Many research work have been made to solve these aforementioned problems.…”

A review of rechargeable batteries for portable electronic devices

“…[83][84][85][86][87][88][89] Along this line, new battery systems have been intensively pursued in recent years, including Li metal batteries, [90][91][92][93][94][95][96] metal-sulfur batteries, 97-104 metal-air (or metal-oxygen) batteries, [105][106][107][108][109] and batteries involving monovalent (eg, Na and K) [110][111][112][113][114][115] or multivalent (eg, Mg, Ca, Zn, and Al) elements/cations. 116 Among various new battery systems, Li-sulfur, Li metal, and Li-oxygen batteries have gained great attraction due to their exceptionally high energy density (Figure 11). In particular, Li-sulfur and Li-oxygen batteries have the theoretical gravimetric energy density of 2600 Wh kg −1 and 3500 Wh kg −1 , respectively.…”