Elastic Binder for High-Performance Sulfide-Based All-Solid-State Batteries

Abstract

Sulfide-based all-solid-state batteries (ASSBs) offer enhanced safety and potentially high energy density. Particularly, an “anode-less” electrode containing metallic seeds that form a solid-solution with lithium was recently introduced to improve the cycle life of sulfide-based ASSB cells. However, this anode-less electrode is gradually destabilized because the metal particles undergo severe volume expansion during repeated cycling. Furthermore, the irreversibility of the electrode in early cycles impairs the energy density of the cell significantly. Herein, we introduce an elastic polymer known as “Spandex” as a binder for the silver–carbon composite. The soft and hard segments of this binder act synergistically in that the former engages in strong hydrogen bonding with the active material and the latter promotes elastic adjustment of the binder network. This binder design significantly improves the charge–discharge reversibility and long-term cyclability of the anode-less ASSB cell and provides insights into elastic binder systems for high-capacity ASSB anodes that undergo a large volume expansion.

In Situ Interweaved High Sulfur Loading Li–S Cathode by Catalytically Active Metalloporphyrin Based Organic Polymer Binders

“…This might be attributed to the strong adhesion and mechanical strength of Mn‐COP that enable to tolerate the volume expansion/contraction during the charge–discharge processes, whereas PVDF chains gradually become scattered and unable to bind the electrode together. [ 50 ] Besides, the obvious cracks on the surface of PVDF/CNT/S electrode suggest that it would be hard for the cathode with PVDF binder to operate under higher sulfur loading conditions. SEM cross‐section images show that the volume expansion of Mn‐COP/CNT/S electrode after cycling is obviously buffered compared with PVDF/CNT/S electrode (Figure S26, Supporting Information).…”

Anode-less all-solid-state batteries: recent advances and future outlook

“…One notable feature that needs to be taken into account when designing the protective layer is that the formation of the Li-metal alloy is accompanied by an immense volumetric change. With this issue in mind, Oh et al attempted to use a highly elastic binder, namely 'Spandex' (figure 2(f)) [36], to replace the conventional poly(vinylidene fluoride) (PVDF) binder. PVDF does not alleviate the volume change Ag undergoes during the alloying reaction with Li, thereby leading to the formation of additional empty space underneath the protective layer and, eventually, the accumulation of dead Li.…”

Prospects for managing end‐of‐life lithium‐ion batteries: Present and future

“…Develop other sustainable batteries: For the moment, the landscape of LIBs is dominated by the NCM series and LiFePO 4 , with slow uptake of all-solid-state batteries and aqueous LIBs. [109,110] The academia and enterprises have joined forces to prosper other secondary alkaline ion batteries, such as sodium-ion batteries (CATL, HiNa Battery, Sunwoda) and potassium-ion batteries. [111][112][113][114][115] The aim is to take the load off the overburdened LIBs in certain cases, while advancing green, safe, and diversified alternatives for energy supply, also as a driver for sustainable development.…”