Unexpected Contribution of Current Collector to the Cost of Rechargeable Al‐Ion Batteries

Abstract

Rechargeable aluminum‐ion batteries (AIBs) are emerging as a promising energy storage technology. However, a series of issues will need to be addressed for the commercialization of AIBs. Anodic dissolution of cheap materials commonly used as cathode current collectors is a great challenge. At laboratory scale, this issue is solved by using expensive/scarce current collectors. The aim of our work is twofold. 1) To quantify the impact of the current collector in the battery cost by performing a cost analysis, which reveals that the current collector is currently the most expensive element in AIBs. 2) To propose the use of carbon‐based current collectors, such as gas diffusion layers (GDLs), which are shown to be an excellent option for AIBs. From an electrochemical perspective, the GDL does not corrode and does not catalyze electrolyte decomposition. Moreover, performances of AIBs using GDLs as current collectors are comparable to those using more expensive state‐of‐the‐art materials, while its use contributes to reducing battery costs.

Aluminum Metal–Organic Batteries with Integrated 3D Thin Film Anodes

“…Here, the use of planar current collector foil, in combination with the use of non‐conductive glass fiber network support, give rise to preferential deposition close to the current collector and, hence, limit long‐term stability. Solutions could be to use gas diffusion layers as conductive 3D network support for Al thin film anodes, which are then integrated with the current collector, [ 31 ] or to sputter a metal seed‐layer on the separator and electrodeposit Al. The latter with possibilities to obtain a more thick and uniform Al thin film throughout the network, and, thus increase the surface area further.…”

A Gel Polymer Electrolyte for Aluminum Batteries

“…[ 1,2 ] One of the main drawbacks of secondary Al batteries is the extremely high corrosivity of the chloroaluminate electrolyte conventionally used for this system. [ 3–8 ] Most of the polymers used as binders or separators and cell cases are not stable in the chloroaluminate melt electrolyte. [ 9–11 ] Furthermore, the metal current collector's corrosion limits the choice to molybdenum or tungsten, unsuitable in practical application for their elevated cost.…”

“…[ 9–11 ] Furthermore, the metal current collector's corrosion limits the choice to molybdenum or tungsten, unsuitable in practical application for their elevated cost. [ 7 ] The identification of chlorine‐free electrolytes, characterized by higher stability against cell components, can overcome these issues. Several efforts have been dedicated to realizing an electrolyte composition with the ability to efficiently strip and deposit aluminum metal and be noncorrosive.…”

AlCl3‐Saturated Ionic Liquid Anolyte with an Excess of AlCl3 for Al–Graphite Dual‐Ion Batteries

“…In a search for inexpensive, large‐scale stationary storage of electricity, non‐aqueous Al‐graphite dual‐ion batteries (AGDIBs) have attracted recently much attention due to the high natural abundances of their primary constituents, the long cycle life of up to a quarter of a million cycles, the high energy efficiency of 80–90 % and facile manufacturing [1–8] . While recent research efforts on AGDIBs have been mainly focused on the judicious selection of carbonaceous cathode materials, leading to the most notable advances in the performance of AGDIBs, [9–27] the major challenge with such batteries is that they lag behind Li‐ion batteries in theoretical cell‐level energy density. As described below in detail, we estimate the energy density limit for widely used chloroaluminate ionic liquid (IL) anolyte–cathode combinations to be ca .…”