Regulating Lithium Ion Transport by a Highly Stretchable Interface for Dendrite-Free Lithium Metal Batteries

Abstract

The lithium metal anode is considered to be the ultimate anode material for high-energy-density rechargeable batteries. However, the application of lithium metal batteries is plagued by Li dendrite growth. Here, we report a flexible polymer (polyacrylic acid–Pluronic, PAF) interface for dendrite-free lithium metal batteries. The lithiophilic groups (ester group) in PAF can coordinate with lithium ions for the uniform distribution of lithium ions at the lithium/electrolyte interface, thus achieving dendrite-free lithium deposition. Moreover, the PAF polymer interface exhibits a high stretchability (278% strain to its initial length) and can tolerate the huge volume change during the plating/stripping processes. Consequently, the symmetric cells with the PAF@Li anode deliver excellent cycling stability over 600 h (1 mA cm–2, 2 mAh cm–2) with a slight overpotential of around 76 mV. Notably, the PAF@Li|LiNi0.8Co0.1Mn0.1O2 full cell exhibits a high capacity retention of 78.5% with a high cathode mass loading (16.5 mg cm–2) even after 190 cycles at 1 C (3.5 mA cm–2).

Advances in functional organic material-based interfacial engineering on metal anodes for rechargeable secondary batteries

“…The electrolyte additives contribute to the in situ formation of an even SEI layer on the metal surface, which will improve the stability of the anode/electrolyte interface and reduce side reactions. [14][15][16] Thirdly, designing an artificial SEI layer. The introduction of artificial SEI layer can effectively avoid the direct contact between the liquid electrolyte and metal anode, reducing the loss of active substances and electrolyte.…”

Silicon Layer on Polymer Electrolyte as a Dendrite Stopper for Stable Lithium Metal Batteries

“…This framework provides balanced ionic and electronic conductivity, acting as a stable Li host and preventing dendrite growth and volume expansion during cycling. 22,24,25 Moreover, the alloying reaction between SiO x and the lithium metal produces Li y Si, which forms a stable interface. 26 Si is oxidized to form SiO x , which can subsequently serve as a core−shell structure with Si@SiO x .…”

“…In previous reports, Si or SiO x has mainly been used as an anode material. , For example, Li y Si particles were evenly distributed to form a porous 3D Li–Si alloy-type interfacial framework, which was utilized by in situ spontaneous prelithiation of Si. This framework provides balanced ionic and electronic conductivity, acting as a stable Li host and preventing dendrite growth and volume expansion during cycling. ,, Moreover, the alloying reaction between SiO x and the lithium metal produces Li y Si, which forms a stable interface . Si is oxidized to form SiO x , which can subsequently serve as a core–shell structure with Si@SiO x .…”