Porous Metal Current Collectors for Alkali Metal Batteries

Abstract

Alkali metals (i.e., Li, Na, and K) are promising anode materials for next-generation high-energy-density batteries due to their superior theoretical specific capacities and low electrochemical potentials. However, the uneven current and ion distribution on the anode surface probably induces undesirable dendrite growth, which leads to significant safety hazards and severely hinders the commercialization of alkali metal anodes. A smart and versatile strategy that can accommodate alkali metals into porous metal current collectors (PMCCs) has been well established to resolve the issues as well as to promote the practical applications of alkali metal anodes. Moreover, the proposal of PMCCs can meet the requirement of the dendrite-free battery fabrication industry, while the electrode material loading exactly needs the metal current collector component as well. Here, a systematic survey on advanced PMCCs for Li, Na, and K alkali metal anodes is presented, including their development timeline, categories, fabrication methods, and working mechanism. On this basis, some significant methodology advances to control pore structure, surface area, surface wettability, and mechanical properties are systematically summarized. Further, the existing issues and the development prospects of PMCCs to improve anode performance in alkali metal batteries are discussed.

Electronical Conductivity Improvement of Carbon-Based Slurry Electrodes Using Carbon Foams for Enhanced Performance in Advanced Electrochemical Energy Storage Systems

“…Moreover, in accordance with the space-charge theory for defining current distribution in a porous CC with a dilute electrolyte, a local space-charge region and electric field develops between the electrolyte and porous CCs . In that region, current density ( J ) is directly impacted by CC spacing (or the shorter length to transport ions and charges) during the rapid charging–discharging process J = 2 italiceCD ( μ a + μ c ) / μ normala L In eq , e and D are the electronic charge and diffusion constants, respectively, C refers to the ion concentration at the initial state, μ a and μ c are the mobilities of anions and cations, respectively, and L is the distance between CCs.…”

“… 98 In that region, current density ( J ) is directly impacted by CC spacing (or the shorter length to transport ions and charges) during the rapid charging–discharging process. 99 In eq 4 , e and D are the electronic charge and diffusion constants, respectively, C refers to the ion concentration at the initial state, μ a and μ c are the mobilities of anions and cations, respectively, and L is the distance between CCs. All of these advantages offered by CF contribute to the enhancement of electronic conductivity.…”

Nucleophilic deposition behavior of metal anodes

“…66 Compared with the stable deposition process and initial sedimentation reaction, the energy required increases.Thus, for the same current density, the inducer plays an important role in the overpotential. Cu substrates, 67–69 which possess poor contact affinity with the Li metal, need the nucleation energy Δ E nuc. and are predicted to have the maximum initial deposition overpotential.…”

Lithiophilic Interface Layer Induced Uniform Deposition for Dendrite-free Lithium Metal Anodes in a 3D Polyethersulfone Frame

“…(III) Anode engineering. , Anode engineering includes lithium metal anode reconstruction, porous current collection, and current collector modification. − Liang’s team designed a mechanical interlocking network as an interfacial layer, combined with a unique energy dissipation capability, to protect the lithium anode and help the Li anode to withstand repeated volume changes during long-term cycling, and the reconstituted Li anode exhibited excellent cycle performance . Ma and Wang’s group constructed a dynamically intelligent Cu (DI Cu) current collector with a tunable pore structure.…”