milerssliu/battery-device-data-qa huggingface dataset:
For the half-cell tests, the electrochemical properties were evaluated using a CR2032 corn-type cell. The cells were prepared in an Ar-filled glove box with H2O and O2 concentrations <0.1 ppm. Si@CTSC, Si@ALGC, Si@PVDFC and Si/PVDF were used as the anodes (diameter: 14 mm), and Li metal foil was used as the counter electrodes (thickness: 300 μm and diameter: 12 mm). A Celgard 2400 polypropylene membrane was used as the separator. The electrolyte was 1 M LiPF6 in a mixture of ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC) (1:1:1 by vol) with 5 wt% fluoroethylene carbonate (FEC). The electrolyte amount was 5 g A h−1. The electrochemical tests were carried out after letting the assembled cells stand for 24 hours to ensure full infiltration of the electrolyte. The GCD measurements were carried on a Land CT2001A system from 0.01 to 2.5 V. CV measurements were performed with sweep rates from 0.2 to 1.2 mV s−1 using a CHI660E work station. The frequency for the EIS measurements ranged from 100 kHz to 10 mHz. GITT tests were carried out using a constant current pulse with a duration of 10 min and a relaxation process over 10 min.

Question: What's the anode?
Answer: Si@CTSC, Si@ALGC, Si@PVDFC and Si/PVDF
For the half-cell tests, the electrochemical properties were evaluated using a CR2032 corn-type cell. The cells were prepared in an Ar-filled glove box with H2O and O2 concentrations <0.1 ppm. Si@CTSC, Si@ALGC, Si@PVDFC and Si/PVDF were used as the anodes (diameter: 14 mm), and Li metal foil was used as the counter electrodes (thickness: 300 μm and diameter: 12 mm). A Celgard 2400 polypropylene membrane was used as the separator. The electrolyte was 1 M LiPF6 in a mixture of ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC) (1:1:1 by vol) with 5 wt% fluoroethylene carbonate (FEC). The electrolyte amount was 5 g A h−1. The electrochemical tests were carried out after letting the assembled cells stand for 24 hours to ensure full infiltration of the electrolyte. The GCD measurements were carried on a Land CT2001A system from 0.01 to 2.5 V. CV measurements were performed with sweep rates from 0.2 to 1.2 mV s−1 using a CHI660E work station. The frequency for the EIS measurements ranged from 100 kHz to 10 mHz. GITT tests were carried out using a constant current pulse with a duration of 10 min and a relaxation process over 10 min.

Question: What's the electrolyte?
Answer: 1 M LiPF6
Ti3C2Tx-based materials have been widely reported as anode materials for supercapacitors and hybrid supercapacitors with the acid electrolyte. Here, the modified Ti3C2Tx MXene (400-KOH-Ti3C2) samples were synthesized based on a previous report. The XRD pattern (Fig. 1a and S1†) reveals that the diffraction peaks of 400-KOH-Ti3C2 shift to a lower 2θ angle compared with those of the original Ti3C2Tx, indicating the increase of interlayer distances after KOH treatment and calcination. In addition, the intensity of partial diffraction peaks for 400-KOH-Ti3C2 is slightly weaker than that of original Ti3C2Tx, suggesting that some feature of the Ti3C2Tx diffraction peaks is shielded by the K+ intercalation into the Ti3C2 MXene layer. Raman spectroscopy (Fig. 1b) and XPS tests (Fig. S2†) were carried out to further manifest the purity and chemical composition of the as-obtained 400-KOH-Ti3C2 samples. To clearly reflect the interlayer spacing for 400-KOH-Ti3C2 samples, the SEM and TEM images are given in Fig. S3† and 1c, respectively. It can be found that 400-KOH-Ti3C2 consisted of stacked MXene nanosheets. The corresponding HRTEM image shows that the interlayer distance of 400-KOH-Ti3C2 is 1.17 nm (Fig. 1d), much larger than that of the original Ti3C2Tx (0.98 nm, Fig. S4†), further confirming the expansion of the interlayer distance after KOH treatment and calcination. In addition, the scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) mapping images of 400-KOH-Ti3C2 clearly indicate that Ti, C, O, F and K elements are homogeneously distributed in all MXene sheets (Fig. S5†).

Question: What's the anode?
Answer: Ti3C2Tx-based materials
The M2+–Fe LDHs (M = Ni, Zn) nanosheets were prepared using a facile electrosynthesis method. Typically, nickel foam (NF, 10 × 30 × 0.05 mm3) was sonicated in 2 M HCl solution for 15 min and subsequently rinsed with water and ethanol to ensure a clean surface. The electrodeposition was carried out in a standard three-electrode system cell containing NF as the working electrode, Pt plate as the counter electrode and Ag/AgCl (3 M KCl) as the reference electrode. The electrolyte for the electrosynthesis of NiFe LDH contained Ni(NO3)2·6H2O (0.03 M) and Fe(NO3)3·9H2O (0.01 M). The total cation concentration in the electrolyte was maintained at 0.04 M. The potentiostatic deposition was then carried out at −1.0 V vs. Ag/AgCl for 300 s at room temperature. The obtained NiFe LDH nanosheets were carefully withdrawn and rinsed thoroughly with water and ethanol and left to dry at 45 °C. The NiZnFe LDHs nanosheets were prepared via a similar method, by replacing Ni(NO3)2·6H2O (0.03 M) with a mixture of Ni(NO3)2·6H2O (0.027 M) and Zn(NO3)2·6H2O (0.003 M).

Question: What's the electrolyte?
Answer: Ni(NO3)2·6H2O (0.03 M) and Fe(NO3)3·9H2O (0.01 M)
EELS spectra are obtained from the thin edge of cycled LLOs as labelled by the orange lines in Fig. 4(a and d) to study oxygen vacancies and TM valence states. Detailed comparisons of O-K, Ni-L, Co-L and Mn-L spectra are presented in Fig. 4(g–j) and S7.† For O-K edges, the intensity of the prepeak (∼530 eV) is sensitive to the valence states of TM ions. The intensity of this prepeak decreases drastically from the interior of the particle to the surface and almost disappears at the surface of the cycled LLOs at the cut-off of 4.8 V (Fig. S7†), indicating a significant decrease of TM valence states. This matches well with the fine changes of Mn-L edges in Fig. 4(h), which show a chemical shift (∼2.5 eV) toward the lower binding energy on the surface (0–10 nm depth), as compared with the cycled bulk (≥30 nm depth). These signatures demonstrate that the majority of Mn ions start to shift to a lower valence at a depth of 20 nm beneath the surface of cycled LLOs at the cut-off of 4.8 V, while for the LLOs cycled at 4.5 V, the reduced valence of dominant Mn ions occurs in the top 10 nm layer beneath the surface (Fig. 4(j)). The valence decrease of Mn ions in LLOs is usually accompanied by Mn dissolution into the electrolyte during cycling, which is measured by ICP-OES as shown in Fig. S8.† The Mn concentration dissolved in the electrolyte at the cut-off of 4.8 V after 100 and 200 cycles reaches 139 and 267 ppm, respectively, which are much higher than the 56 and 97 ppm at 4.5 V. These results confirm the reduced Mn dissolution into the electrolyte for the LLOs cycled at the low cut-off of 4.5 V.

Question: What's the electrolyte?
For the first cycle in LP30 a more apparent “pitting” peak is observed that occurs at an earlier time compared to LP30 + FEC (occurring at ∼78% and ∼92% capacity, respectively for 0.5 mA cm−2). Other studies have suggested that this is due to inhomogeneous dissolution of the lithium whiskers that result in dead Li formation and early peaking behaviour. However, the lower plating efficiency quantified with in situ NMR can also lead to the early peaking behaviour observed when lower amounts of microstructures are present. With 1 and 2 mA cm−2, the peaking in the first cycle (where the stripping current is kept at 1 mA cm−2) occurs at 85% and 89% capacity respectively. This correlates well with the in situ NMR, which indicated higher plating efficiencies for the higher current densities in LP30. The voltage traces are flatter for the LP30 + FEC electrolyte, as compared to those for LP30, consistent with both the higher plating efficiency seen in the in situ NMR and of studies showing minuscule dead lithium formation in LP30 + FEC. The lower overpotential observed for LP30 + FEC is somewhat consistent between cells (Fig. S2–S4†), but the overpotential is affected both by the resistances in the cell (in particular of the SEI) and the surface area (which increases during electrodeposition) accounting for variations between cells.

Question: What's the electrolyte?
Answer: LP30 + FEC
(2) A Ti metal precursor is anodized in an alkali electrolyte (e.g. NaOH and Ba(OH)2 solutions). The alkaline anodization (Fig. 6B) could be considered an electro-assisted hydrothermal-like process with 2 stages where TiO2·2H2O anodized from the titanium anode reacts with the hot alkaline surroundings generated by a continuous electric field. In the first stage, a fast anodic reaction on the titanium surface creates a thin TiO2·2H2O nanosheet layer (eqn (1) and (2)) which would react with alkali to form titanate nanowire bundles on the titanium anode (eqn (3)). In particular, it should be mentioned that the OH− concentration should be above 4 M to ensure the formation of titanate rather than titania. In the second stage, the anodized TiO2·2H2O would also break down and disperse into the electrolyte to form a 3D hierarchical porous structure with a large specific surface area.

Question: What's the anode?
Answer:  titanium
(2) A Ti metal precursor is anodized in an alkali electrolyte (e.g. NaOH and Ba(OH)2 solutions). The alkaline anodization (Fig. 6B) could be considered an electro-assisted hydrothermal-like process with 2 stages where TiO2·2H2O anodized from the titanium anode reacts with the hot alkaline surroundings generated by a continuous electric field. In the first stage, a fast anodic reaction on the titanium surface creates a thin TiO2·2H2O nanosheet layer (eqn (1) and (2)) which would react with alkali to form titanate nanowire bundles on the titanium anode (eqn (3)). In particular, it should be mentioned that the OH− concentration should be above 4 M to ensure the formation of titanate rather than titania. In the second stage, the anodized TiO2·2H2O would also break down and disperse into the electrolyte to form a 3D hierarchical porous structure with a large specific surface area.

Question: What's the electrolyte?
Answer: alkali
(2) A Ti metal precursor is anodized in an alkali electrolyte (e.g. NaOH and Ba(OH)2 solutions). The alkaline anodization (Fig. 6B) could be considered an electro-assisted hydrothermal-like process with 2 stages where TiO2·2H2O anodized from the titanium anode reacts with the hot alkaline surroundings generated by a continuous electric field. In the first stage, a fast anodic reaction on the titanium surface creates a thin TiO2·2H2O nanosheet layer (eqn (1) and (2)) which would react with alkali to form titanate nanowire bundles on the titanium anode (eqn (3)). In particular, it should be mentioned that the OH− concentration should be above 4 M to ensure the formation of titanate rather than titania. In the second stage, the anodized TiO2·2H2O would also break down and disperse into the electrolyte to form a 3D hierarchical porous structure with a large specific surface area.

Question: What's the anode?
Answer: titanium
(2) A Ti metal precursor is anodized in an alkali electrolyte (e.g. NaOH and Ba(OH)2 solutions). The alkaline anodization (Fig. 6B) could be considered an electro-assisted hydrothermal-like process with 2 stages where TiO2·2H2O anodized from the titanium anode reacts with the hot alkaline surroundings generated by a continuous electric field. In the first stage, a fast anodic reaction on the titanium surface creates a thin TiO2·2H2O nanosheet layer (eqn (1) and (2)) which would react with alkali to form titanate nanowire bundles on the titanium anode (eqn (3)). In particular, it should be mentioned that the OH− concentration should be above 4 M to ensure the formation of titanate rather than titania. In the second stage, the anodized TiO2·2H2O would also break down and disperse into the electrolyte to form a 3D hierarchical porous structure with a large specific surface area.

Question: What's the electrolyte?
Answer: (e.g. NaOH and Ba(OH)2 solutions)
According to the simulation, the number of moles per surface area formed in the two electrolytes, NSEI (Fig. S17a†) is also greater for the LP30 + FEC electrolyte, indicating a thicker SEI is being formed. We have estimated the thickness of the SEI by using eqn (13) and assuming it to be pure Li2CO3 so as to provide a qualitative understanding of the extent of SEI formation. Averaging over the whole experiment (74 hours) the SEI formation rate is 6.1 nm h−1 in LP30 and 12 nm h−1 for LP30 + FEC. The values are relatively large and seem to overestimate the thickness of the SEI but are on a similar scale to what was estimated in an earlier isotope exchange study (14 nm h−1 in LP30). One possible reason for this overestimation of thickness is the assumption that all of the reduced electrolyte species are deposited to form the SEI. However, it has been shown experimentally that a wide range of the reduced electrolyte species are soluble and go into the electrolyte. We also note that the comparison of SEI thicknesses needs to be interpreted with caution as the chemical composition and density is expected to differ between the two electrolytes.

Question: What's the electrolyte?
Answer: LP30 + FEC
Next, the annealed WO3−x film was assembled into an electrochromic device to test its functionality. The device structure is shown in Fig. 3a, in which the FTO glass is used as the transparent electrode. The electrolyte with 1.25 M LiClO4 in a mixed solvent was used in the electrochromic device to achieve the insertion and extraction of Li+ ions in the WO3−x film. The device in the bleached state shows a high transmittance in both the visible and infrared wavelength range (Fig. 3b), while in the colored state, the transmittance of the electrochromic device decreases significantly. At the wavelength of 680 nm, the transmittance difference between the two curves is around 70%. In the wavelength range of 700–1000 nm, the transmittance of the colored state is even less than 3%, indicating the excellent near infrared light shielding ability. Hence, in the scorching summer, smart windows made of this electrochromic WO3−x film can keep the room cool by blocking heat radiation. Fig. 3c shows the photographs of the packaged electrochromic device in the coloring and bleaching process. A series of different color states from light to deep blue can be easily obtained by adjusting the applied bias from −3.5 V to 3.5 V, which may have potential applications in the field of electrochromic displays.

Question: What's the electrolyte?
Answer: 1.25 M LiClO4
Intermetallic Mg2Sn alloyed with extra Mg was presented as a new high-performance anode for MIBs. The 3Mg/Mg2Sn was composed of c-Mg, a-Mg, and Mg2Sn, and showed excellent electrochemical performance when cycled in Mg(HMDS)2:MgCl2/THF. During the 1st de-magnesiation, 3Mg/Mg2Sn first dissolved Mg2+ from c-Mg, which was then followed by the complete conversion of Mg2Sn to Sn with a partial release of a-Mg. The irreversible dissolution of c-Mg facilitated the reversible de-magnesiation/magnesiation in Mg2Sn and a-Mg, and allowed 3Mg/Mg2Sn to demonstrate unprecedented electrochemical properties. Thanks to the high surface area and pore volume ascribed to the irreversible dissolution of c-Mg, the 3Mg/Mg2Sn anode delivered reversible capacities of 805 and 430 mA h g−1 at 100 and 1500 mA g−1, respectively, with reasonable cycling stability. De-magnesiated 3Mg/Mg2Sn also showed similar electrochemical performance in other conventional electrolyte systems (Mg(TFSI)2:MgCl2/diglyme and Mg(TFSI)2/acetonitrile). In addition to the beneficial role of c-Mg with respect to the electrochemical properties of 3Mg/Mg2Sn in a half-cell configuration, irreversibly dissolved Mg2+ ions could ideally balance the Mg2+ ions trapped in a Mo6S8 cathode in a full-cell.

Question: What's the cathode?
Answer: Mo6S8
Intermetallic Mg2Sn alloyed with extra Mg was presented as a new high-performance anode for MIBs. The 3Mg/Mg2Sn was composed of c-Mg, a-Mg, and Mg2Sn, and showed excellent electrochemical performance when cycled in Mg(HMDS)2:MgCl2/THF. During the 1st de-magnesiation, 3Mg/Mg2Sn first dissolved Mg2+ from c-Mg, which was then followed by the complete conversion of Mg2Sn to Sn with a partial release of a-Mg. The irreversible dissolution of c-Mg facilitated the reversible de-magnesiation/magnesiation in Mg2Sn and a-Mg, and allowed 3Mg/Mg2Sn to demonstrate unprecedented electrochemical properties. Thanks to the high surface area and pore volume ascribed to the irreversible dissolution of c-Mg, the 3Mg/Mg2Sn anode delivered reversible capacities of 805 and 430 mA h g−1 at 100 and 1500 mA g−1, respectively, with reasonable cycling stability. De-magnesiated 3Mg/Mg2Sn also showed similar electrochemical performance in other conventional electrolyte systems (Mg(TFSI)2:MgCl2/diglyme and Mg(TFSI)2/acetonitrile). In addition to the beneficial role of c-Mg with respect to the electrochemical properties of 3Mg/Mg2Sn in a half-cell configuration, irreversibly dissolved Mg2+ ions could ideally balance the Mg2+ ions trapped in a Mo6S8 cathode in a full-cell.

Question: What's the anode?
Answer: 3Mg/Mg2Sn
Intermetallic Mg2Sn alloyed with extra Mg was presented as a new high-performance anode for MIBs. The 3Mg/Mg2Sn was composed of c-Mg, a-Mg, and Mg2Sn, and showed excellent electrochemical performance when cycled in Mg(HMDS)2:MgCl2/THF. During the 1st de-magnesiation, 3Mg/Mg2Sn first dissolved Mg2+ from c-Mg, which was then followed by the complete conversion of Mg2Sn to Sn with a partial release of a-Mg. The irreversible dissolution of c-Mg facilitated the reversible de-magnesiation/magnesiation in Mg2Sn and a-Mg, and allowed 3Mg/Mg2Sn to demonstrate unprecedented electrochemical properties. Thanks to the high surface area and pore volume ascribed to the irreversible dissolution of c-Mg, the 3Mg/Mg2Sn anode delivered reversible capacities of 805 and 430 mA h g−1 at 100 and 1500 mA g−1, respectively, with reasonable cycling stability. De-magnesiated 3Mg/Mg2Sn also showed similar electrochemical performance in other conventional electrolyte systems (Mg(TFSI)2:MgCl2/diglyme and Mg(TFSI)2/acetonitrile). In addition to the beneficial role of c-Mg with respect to the electrochemical properties of 3Mg/Mg2Sn in a half-cell configuration, irreversibly dissolved Mg2+ ions could ideally balance the Mg2+ ions trapped in a Mo6S8 cathode in a full-cell.

Question: What's the electrolyte?
Answer: Mg(TFSI)2:MgCl2/diglyme and Mg(TFSI)2/acetonitrile
A button-sized hybrid electrolyte cell (Fig. S4†), in which an ionic liquid-infiltrated NCM with a LLZTO electrolyte and a 20 μm–thick Li metal were respectively used as a cathode and a Li metal anode, was fabricated to check out the improvement of the electrochemical performance after laser-annealing treatment. For comparison, two kinds of LLZTO pellets were used: a polished pellet without laser treatment and a laser-treated pellet. In Fig. 6a and b, the Nyquist plots of the AC-impedance spectra from the samples obtained at an open circuit from the cells were compared. As shown in Fig. 6a and b, the ohmic losses calculated from the high-frequency intercept with the real axis were almost the same in the range of 3.2–4.0 Ω cm2 for both the cells. Based on the ohmic resistance, the ionic conductivities were expected to be in the range of 7.5–9.4 10−3 S cm−1 at 60 °C for the LLZTO pellets with and without laser treatment. These conductivity values are consistent with the reported values of Ta-doped LLZO and also with that value (∼8.6 × 10−3 S cm−1 at 60 °C) experimentally obtained from the Au-sputtered symmetric cells (Au/LLZTO/Au), as shown in Fig. S5a.† Thus, it can be inferred that the cathode and ionic liquid catholyte are not contributing significantly to the ohmic losses in these cells. Furthermore, the amorphous layer formed by laser irradiation had no significant effect on the ohmic resistance due to its low thickness of about 400 nm. The AC-impedance spectra of both cells consist of a depressed arc in the high-frequency range, a narrow line inclined at a constant angle to the real axis (Warburg impedance), and a capacitive line (blocking region) in the low-frequency range, which are typical features of a NCM-Li cell. The high-frequency arc could be associated with the charge-transfer reactions at the cathode and anode interface. Because the relaxation times for the cathodic and anodic reactions are generally overlapped over the high-frequency ranges for a NCM-Li full cell, it is difficult to separate the charge-transfer resistance at the Li-LLZTO interface from the resistance at the NCM-ionic liquid. The AC-impedance spectrum for Li/LLZTO/Li cell is also shown in Fig. S5b.† Considering that the electrochemical kinetics at the cathode would be almost the same for both cells, the variation in the high-frequency arc could be attributed to the charge-transfer resistance at the Li metal and LLZTO interface. The values of the overall interfacial resistance, Rct, were quantitatively determined from complex non-linear least-square (CNLS) fitting of the measured impedance spectra based on a typical equivalent circuit of the NCM-Li full cell. The Rct (Rc + Ra) value was reduced from ∼80 Ω cm2 to ∼26 Ω cm2 when the LLZTO surface was treated by a laser beam. In addition, as shown in Fig. S5c,† the electronic conductivity of LLZTO was significantly reduced by the laser treatment, which can originate from the formation of a wide band gap surface layer.

Question: What's the cathode?
Answer: NCM