Ternary bulk heterojunction (BHJ) blends have been demonstrated as a promising approach to increase the power conversion efficiencies (PCEs) of organic solar cells. Currently, most studies of ternary organic solar cells are based on blends of two donors and one acceptor, because of the limitation in acceptor materials. Here, we report that high-performance ternary solar cells have been fabricated with a wide-bandgap polymer donor (PDBT-T1) and two acceptor materials, phenyl-C70-butyric acid methyl ester (PC 70 BM), and nonfullerene acceptor (ITIC-Th). The addition of ITIC-Th into the BHJ blends dramatically increases the light absorption. Consequently, the champion ternary solar cell shows a high PCE of ∼10.5%, with an open-circuit voltage (V oc ) of 0.95 V, a short-circuit current (J sc ) of 15.60 mA/cm 2 , and a fill factor (FF) of 71.1%, which largely outperforms their binary counterparts. Detailed studies reveal that the ternary solar cells work in a parallel-like device model (ITIC-Th and PC 70 BM form their own independent transport network) when ITIC-Th loading is >30% in the ternary blends. The results indicate that the combination of fullerene derivative and appropriate nonfullerene acceptor in a ternary blend can be a new strategy to fabricate high-performance ternary organic solar cells.

The advancements in wearable electronic devices make it urgent to develop highperformance flexible lithium-ion batteries (LIBs) with excellent mechanical and electrochemical properties. Herein, we design a new 3D hierarchical hybrid sandwich flexible structure by anchoring SnO 2 nanosheets (SnO 2-NSs) on flexible carbon cloth and coating with thin amorphous carbon (AC) layer (CF@SnO 2-NS@AC). The carbon cloth substrate works as the backbone and the current collector, while the thin AC layer provides extra support during the electrode expansion. The new architecture can be utilised as a binder-free electrode and presents extraordinary mechanical flexibility and outstanding electrical stability under external stresses. The new electrode can deliver a specific capacity as high as 968.6 mAh g-1 after 100 cycles at 85 mA g-1 , which also shows remarkable rate capability and an excellent high current cycling stability. The outstanding electrochemical performance combined with the high mechanical flexibility and invariable electrical conductivity during/after different bending cycles make the new structure a promising oxide anode for flexible batteries. With the possibility of using a similar approach to design flexible cathode, the present work opens the door to empower the next-generation wearable devices and smart clothes with a robust and reliable battery.

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The lithium metal anode (LMA) instability at deep cycle with high utilization is a crucial barrier for developing lithium (Li) metal batteries, resulting in excessive Li inventory and electrolyte demand. This issue becomes more severe in capacity‐type lithium–sulfur (Li–S) batteries. High‐concentration or localized high‐concentration electrolytes are noted as effective strategies to stabilize Li metal but usually lead to a high electrolyte density (>1.4 g mL−1). Here we propose a bifunctional fluorinated silane‐based electrolyte with a low density of 1.0 g mL−1 that not only is much lighter than conventional electrolytes (≈1.2 g mL−1) but also form a robust solid electrolyte interface to minimize Li depletion. Therefore, the Li loss rate is reduced over 4.5‐fold with the proposed electrolyte relative to its conventional counterpart. When paired with onefold excess LMA at the electrolyte weight/cell capacity (E/C) ratio of 4.5 g Ah−1, the Li–S pouch cell using our electrolyte can survive for 103 cycles, much longer than with the conventional electrolyte (38 cycles). This demonstrates that our electrolyte not only reduces the E/C ratio but also enhances the cyclic stability of Li–S batteries under limited Li amounts.