Anode-less seawater batteries with a Na-ion conducting solid-polymer electrolyte for power to metal and metal to power energy storage

Abstract

Seawater batteries (SWBs) have been mostly researched for large scale energy storage and (sub-) marine applications. In a SWB, the aqueous catholyte (seawater) and a non-aqueous anolyte (aprotic solvent solution)...

Hydroxide ion-conducting viologen–bakelite organic frameworks for flexible solid-state zinc–air battery applications

“…The overall bandgap will be much larger, and typically in the semiconducting regime. 31 However, the redox active localized regions are sufficient to set-up a push–pull effect, which would govern the movement of the hydroxide ions.…”

“…30 Polymers have been intensely probed for their stability advantage. 31 Recently, amide polymers constructed from simple monomers (acyl chloride + melamine) were shown to possess strengths comparable to steel. 32 This inspired us to explore the potential of simple systems such as Bakelite and viologen for this task-specific application.…”

Solvent‐free Ternary Polymer Electrolytes with High Ionic Conductivity for Stable Sodium‐based Batteries at Room Temperature

“…Our group recently demonstrated the applicability of a ternary SPE comprising cross-linked PEO, NaFSI and the N-butyl-N-methylpyrrolidinium IL Pyr 14 FSI (63 wt.%) combined with a NASICON (Na 3 Zr 2 Si 2 PO 12 ) ISE in a layered composite in anode-less sodium seawater batteries at 20 °C for power to metal/metal to power energy storage. [22] In this work, solvent-free ternary polymer electrolytes based on PEO, sodium salts (NaFSI or NaTFSI) and N-butyl-N-methylpyrrolidinium ILs (Pyr 14 FSI or Pyr 14 TFSI) were investigated to replace the conventional non-aqueous liquid electrolyte in sodium-based batteries. A high IL plasticizer content is expected to achieve a good RT ionic conductivity while crosslinking of the polymer chains is utilized to maintain mechanical stability.…”

Sacrificial Catalyst of Carbothermal-Shock-Synthesized 1T-MoS2 Layers for Ultralong-Lifespan Seawater Battery

“…Na-based secondary batteries have been proposed as a potential alternative to LIBs and have shown promising electrochemical results. − ,− Additionally, the abundance of Na (∼2.3% of the Earth’s crust) not only provides cost-effectiveness and a sustainable supply for the fabrication of secondary batteries but also realizes a theoretical specific capacity of 1160 mAh g –1 . − ,− The advantages of using Na in secondary batteries can be maximized using a combination of seawater electrolytes because the nonflammable and semi-infinite seawaterwhich has a salinity of 3.5%provides sufficient Na-ion concentrations during battery operation, thereby eliminating the requirement of conventional Na-containing salts for fabricating electrolyte. ,,, However, the high reactivity of Na metal against aqueous solvents hinders its use as an anode, which is a major obstacle in the development of Na-metal-based batteries. , To solve this fatal issue, a seawater battery comprising Na metal, Na superionic conductor (NASICON)-type solid electrolytes which prevent the physical contact between a seawater and Na metal, and a seawater catholyte has been shown to exhibit decent electrochemical characteristics based on the following overall cell reaction: 4Na + O 2 + 2H 2 O ↔ 4NaOH ( E cell = 3.48 V versus Na/Na + ). ,,,− …”

“…8,9,19,20 However, the high reactivity of Na metal against aqueous solvents hinders its use as an anode, which is a major obstacle in the development of Na-metal-based batteries. 21,22 To solve this fatal issue, a seawater battery comprising Na metal, Na superionic conductor (NASICON)-type solid electrolytes which prevent the physical contact between a seawater and Na metal, and a seawater catholyte has been shown to exhibit decent electrochemical characteristics based on the following overall cell reaction: 4Na + O 2 + 2H 2 O ↔ 4NaOH (E cell = 3.48 V versus Na/Na + ). 8,9,19,23−25 One of the urgent issues of seawater batteries so far is the high overpotential of seawater batteries during the charging process (>4.0 V; versus Na/Na + ), which ultimately erodes the cell performance via the corrosion of conventional carbonbased current collectors.…”