Fast Charging All Solid‐State Lithium Batteries Enabled by Rational Design of Dual Vertically‐Aligned Electrodes

Abstract

The slow charging limitations of all-solid-state lithium batteries (ASSLBs) have significantly limited their practical application. Thus, significant improvement of the rate performance and development of fast charging ASSLBs is crucial for the commercialization of these systems. However, poor Li + transport kinetics and Li dendrite formation under high charging current densities have inhibited their capabilities. To tackle these issues, the design of dual vertically-aligned electrodes (DVAEs) is proposed to accelerate Li + transport and suppress Li dendrite formation. At the anode side, the vertically-aligned Li (VA-Li) anode with lithiophilic micro-walls enables lateral growth of Li deposits rather than perpendicular to the electrode surface, thus preventing dendrite penetration through the separator. In addition, the 3D vertically-aligned structure in both VA-Li and vertically-aligned-LiFePO 4 (VA-LFP) enables enhanced Li + transport due to lower tortuosity and faster Li + transport kinetics. Benefitting from the rational design, VA-Li symmetric cells can operate for 300 h at a current density/capacity of 3 mA cm −2 /3 mAh cm −2 , while short-circuiting is observed after 87 h for bare Li cycled at only 0.5 mA cm −2 (capacity: 0.5 mAh cm −2). Moreover, a fast-charging ASSLBs assembled with DVAEs demonstrates a high capacity of 89.4 mAh g −1 after 2000 cycles at 4C.

From Fundamental Understanding to Engineering Design of High‐Performance Thick Electrodes for Scalable Energy‐Storage Systems

“…The lowest tortuosity (τ = 1) can be obtained when the ion transport pathway is composed of aligned channels parallel to the diffusion direction. [ 38 ] Vertically aligned porous electrodes can be prepared by approaches including ice templating, [ 39–42 ] magnetic alignment, [ 43,44 ] wood templating, [ 13,45 ] solvent evaporation, [ 10 ] phase inversion, [ 46–48 ] etc.…”

Fast Ion Transport in Li‐Rich Alloy Anode for High‐Energy‐Density All Solid‐State Lithium Metal Batteries

“…As shown in Figure S2, Supporting Information, there is a strong affinity to the template, and the LiRLIA electrode is completely infused with molten Li‐rich metal alloy after about 40 s. This infusion process is similar to our previous work for the design of the VA‐Li electrodes. [ 17 ] The morphology of the LiRLIA electrode at the micro‐level is characterized by SEM, as shown in Figure S3, Supporting Information. From the top view, the microstructure is different from the vertically aligned template, suggesting a successful Li‐rich metal alloy infusion process.…”

Direct Ink Writing of Moldable Electrochemical Energy Storage Devices: Ongoing Progress, Challenges, and Prospects

“…With the vertically aligned architecture fabricated by 3D printing, an assembled Li//Li symmetric cells displayed a long lifespan over 3000 h at a current of 1 mA·cm −2 , and stable cycling life of 1500 h and sustained it for 400 h, even at ultrahigh currents of 10 and 20 mA·cm −2 , respectively. When coupled with the similar vertically aligned LFP cathode to fabricate a solid‐state battery, [ 54 ] SPE‐based Li‐LFP full cells delivered high capacities of 147, 129, and 112 mAh·g −1 at C rates of 2, 3, and 4 C, which are higher than that of the LFP/VA‐Li cells (116, 97, and 88 mAh·g −1 ). When the C rate returned to 0.5 C, a high capacity of 165 mAh·g −1 was recovered, indicating good stability while cycling at high current densities (Figure 7g).…”