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Lv et al. Energy Mater 2024;4:400018 https://dx.doi.org/10.20517/energymater.2023.90 Page 3 of 11

EXPERIMENTAL
Materials
Gallium ingot (99.99% purity), Indium and Tin pellets (99.995% purity), and tungsten powder (99.9%
purity, φ 50 nm) were purchased from Zhongnuo Advanced Material (Beijing) Technology Co., Ltd. The Cu
foil (CF) was purchased through Shanghai Hesen Electrical Co., Ltd. All chemicals were used without
further purification.

Preparation of materials and electrodes
The synthesis of LM (GaInSn) was carried out in an Ar-filled glove box (H O, O < 0.1 ppm). The
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proportion of LM was Ga:ln:Sn = 7:2:1 (wt.%), placed in a nickel crucible, heated at 200 °C for 1 h, and
constantly agitated to ensure that all components were distributed equally. The composite was collected
after natural cooling. The LM and W (φ 50 nm) powders were weighed according to the mass ratio of 95:5,
90:10, 85:15, named LM-W5, LM-W10, and LM-W15, respectively, constant clockwise grinding using an
agate mortar and pestle in the air until the LM form a paste-like consistency. The theoretical gravimetric
capacity of the LM-W10 is 756 mAh/g (10 wt.% inactive W does not provide capacity). The commercial CF
was cut into round pieces with a diameter of 14 mm, and the LM/CF, LM-W5/CF, LM-W10/CF and
LM-W15/CF were fabricated to spread evenly onto the CF surface with a scraper, respectively (mass loading
approximately 5 mg/cm ). In long-life symmetric cells, the Li/LM-W10/CF and Li/LM/CF were prestored
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with 1 or 2 mAh/cm of Li, respectively. The pre-store process is to assemble the LM-W10/CF or LM/CF
and the LM sheet into a half cell through an electrochemical deposition method; the current density is
0.5 mA/cm , and the voltage range is set to -0.01-3 V. The pre-store process of LM-W10/CF involved first
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conducting charge/discharge for five cycles in the half cells before depositing the amount of lithium
required; however, due to the poor cycle stability of LM/CF, it can only deposit lithium directly. In full cells,
the Li/LM-W10/CF and Li/LM/CF anodes were activated for one cycle at 0.1 C before long-life cycling.

Characterizations
The contact angle was tested by dropping materials on a glass slide at room temperature by a measurement
instrument (JC2000D1, China). The morphology was observed by using an optical microscope (Keyence-
VHX-950F) and scanning electron microscopy (SEM, Verios 460L, FEI). The surface elemental information
was analyzed by an X-ray photoelectron spectrometer (XPS, ESCALAB 250Xi, ThermoFisher Scientific) and
C1s (284.60 eV) as the reference line. X-ray diffraction (XRD) measurements were obtained from a Rigaku
(MiniFlex 600) apparatus equipped with a Cu Kα radiation source. Cyclic voltammetry (CV) and
electrochemical impedance spectroscopy (EIS) were tested by an electrochemical workstation (CHI 760E).
EIS was performed at 10 Hz with an amplitude of 1 mV.
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Battery assembly and electrochemical measurements
The electrochemical performance was carried out on CR2032. Celgard2400 was used as a separator.
Symmetric cells with two identical electrodes were built; the electrolyte was 1 M lithium
bis(trifluoromethanesulfonyl)imide (LiTFSI) solution in 1,3-dioxolane (DOL) and dimethoxymethane
(DME) (1:1 by volume) with 1 wt.% LiNO additive. In full cells, all anodes (Li/LM-W10/CF, Li/LM/CF,
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Li/CF) were prestored 0.5 mAh/cm of Li and then assembled into full cells with LiFePO (LFP) cathodes.
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The pre-store process refers to the previous section. The electrolyte was 1 M LiPF in Ethylene carbonate/
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Diethyl carbonate (1:1 v/v); the cathode composition was LFP, acetylene black and Polyvinylidene fluoride
at a weight ratio of 7:2:1 (mass loading 3-4 mg/cm ). The test voltage range was from 2 to 3.8 V.
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