milerssliu/battery-device-data-qa huggingface dataset:
qas: question: What's the electrolyte?
context: Electrolyte additives may modify lithium deposition in several different ways, e.g. by influencing initial SEI formation on the current collector, the nucleation stage of lithium metal deposition, the growth of lithium metal deposits, or some combination thereof. To investigate during which step of lithium metal electrodeposition HF plays an active role, a cell was first galvanostatically brought down to 0 V vs. the counter electrode (CE, Li/Li+) at 0.5 mA cm−2 in LP30 containing 100 ppm added HF to form the initial SEI on copper (Fig. 3a). The electrolyte was then removed, the cell rinsed with as-received LP30, and refilled with as-received LP30 for deposition of lithium metal (Fig. 3b). There is no voltage plateau ∼2 V indicative of HF reduction, but we observe an additional small amount of capacity below 1 V which is consistent with solvent reduction. Lithium metal with a highly monodispersed columnar morphology (Fig. 3c) was still deposited although there was no HF in the electrolyte during electroplating. This demonstrates that it is the initial SEI on copper which directs the microstructure and that HF does not play an active role beyond the initial SEI formation. This experimental evidence is in agreement with studies in the literature that report the formation of a columnar microstructure without additives when a LiF rich layer was deposited ex situ on copper prior to cell assembly.
qas: question: What's the cathode?
answers: answer_id: 81104
question_id: 66158
text:  lithiated manganese oxides
question: What's the cathode?
answers: answer_id: 81105
question_id: 66161
text: LMO
context: The fabrication of the nanomesh-based cathodes is performed in several steps, starting from the formation of the AAO template, growth of the nanomesh, deposition of the active material precursor and finally its activation by reaction with a lithium source (Fig. 1). In our approach, we focused on lithiated manganese oxides (here, generally abbreviated as LMO) as the active cathode material since they can be synthesized at relatively low temperatures and their precursor (MnO2) can be easily conformally electrodeposited onto high aspect ratio structures. This made LMO the natural choice for demonstrating the potential of nanomesh-based electrodes for Li-ion batteries. It is worth noting that LMO also show a relatively high reduction potential vs. Li+/Li (for example, ∼2.9 V for the layered LiMnO2 and 4–3 V for spinel LiMn2O4 ( ), are cheap and not toxic, but suffer from limited stability when cycled in liquid electrolytes.
qas: question: What's the cathode?
context: Acoustic wave velocity is determined by the speed of wave propagation through a medium with defined thickness. While the wave arrival time can be determined from the measured acoustic signal, thickness must be measured independently to verify the wave velocity. The expansion and contraction of a pouch cell during cycling can be imaged with transmission X-ray microscopy (TXM), which has sufficient range and pixel resolution to measure both the total cell thickness and the average layer thicknesses. TXM parameters were optimized with exposure time of 20 seconds, beam voltage of 140 kV, a 0.4× objective lens and 90° projection angle (Table 1). Fig. 1 illustrates the experimental configuration and example radiographs of the mechanical expansion of a pouch cell upon cycling. The commercial pouch cell chosen (LiCoO2/graphite, 210 mA h nominal capacity) has a total thickness of approximately 5.6 mm when fully charged. The measured thickness varies between 5.4 and 5.6 mm (∼4% change) at a rate of 1C. There is less variation (∼0.5%) at a rate of 3C because of less attainable capacity before hitting the 4.5 V voltage cutoff on charge. The thickness changes are dominated by the ∼10% volume expansion and contraction of graphite anodes upon lithiation/delithiation. With 15 double-sided anodes and cathodes, each of the 30 cell layers (one layer is defined as an anode, a cathode, with a separator layer in between each electrode) is approximately 170 μm in thickness as measured by average peak-to-peak spacing (additional information on pixel thresholds for thickness measurements can be found in Fig. S1–S5†).
qas: question: What's the cathode?
context: Then, Na metal was placed on the surface of the UV curing polymer electrolyte, and the product of a cell test in which a Na metal/solid electrolyte/cathode was made was placed in a 2032-coin cell. All steps were processed in a glovebox with less than 10 ppm for both oxygen and moisture. When manufacturing the bipolar stacked cell, a coin cell was prepared by putting Al foil between the two solid electrolyte cells.
qas: question: What's the cathode?
answers: answer_id: 228503
question_id: 66158
text: COG@MnO2
question: What's the anode?
answers: answer_id: 228547
question_id: 66159
text: COG@Zn
question: What's the electrolyte?
answers: answer_id: 228477
question_id: 66160
text: 2 M ZnSO4 and 0.1 M MnSO4
context: In order to evaluate the electrochemical performance of the obtained electrodes, two-electrode Zn–MnO2 batteries were assembled using COG@MnO2 as the cathode and COG@Zn as the anode in an aqueous electrolyte containing 2 M ZnSO4 and 0.1 M MnSO4. The typical cyclic voltammetry (CV) curves of the aqueous COG@MnO2//COG@Zn battery at different scan rates are shown in Fig. 3d. There are two reduction peaks at around 1.2 and 1.4 V, which should be ascribed to the zinc insertion into MnO2 and the subsequent reduction of Mn(IV) to the Mn(III)/Mn(II) states. Similarly, the oxidation peak and shoulder appear at 1.6–1.8 V, corresponding to Zn-extraction from the MnO2 cathode as the Mn(III)/Mn(II) states undergo oxidation to the Mn(IV) state. The overall reaction of the battery can be formulated as follows:
qas: question: What's the cathode?
answers: answer_id: 84152
question_id: 66158
text: CNF
context: The UTCNF//Zn and CNF//Zn batteries were assembled using UTCNF or CNF cathodes (an area of 1 × 1 cm2 and a thickness of 0.15 cm) and a Zn plate anode with 6 M KOH + 0.5 M Zn(Ac)2 as the electrolyte. The total mass of the UTCNF electrode was ∼32.3 mg and the corresponding hydroxide formation rate was ∼18.6%. Galvanostatic charge–discharge (GCD) experiments were performed using a multichannel battery testing system (Land CT 2001A). Cyclic voltammetry (CV) curves and electrochemical impedance spectra (EIS) were collected on an electrochemical workstation (PARSTAT MC).
qas: question: What's the cathode?
answers: answer_id: 84154
question_id: 66158
text: MnO2 
context: In summary, active catholyte has been applied to assemble a high-performance hybrid supercapacitor, which relies on the reversible conversion between soluble Mn2+ and solid MnO2 at the cathode and the redox of Ti–O with the bonding/de-bonding of H3O+ at the 400-KOH-Ti3C2 anode. The well-separated potential window between the cathode and anode leads to a hybrid supercapacitor with a wide voltage window of 1.7 V. This hybrid supercapacitor achieves a high energy density of 43.4 W h kg−1, without using any ion-selective membrane, and super-long cycle life (75% retention after 20000 cycles). Furthermore, the hybrid supercapacitor can operate well even with the frozen electrolyte at −70 °C. These inspiring results provide a new strategy to design high-performance hybrid supercapacitors for low temperature applications.
qas: question: What's the cathode?
answers: answer_id: 228497
question_id: 66158
text: MoP@NiCo-LDH/NF-20
question: What's the anode?
answers: answer_id: 228552
question_id: 66159
text: MoP@NiCo-LDH/NF-20 electrode 
question: What's the electrolyte?
context: In summary, MoP was synthesized on nickel foam, on which NiCo-LDH was electrodeposited to form catalyst electrodes (MoP@NiCo-LDH/NF-x), where x represents the electrodeposition time period, and they were explored as bifunctional catalysts for both the hydrogen evolution reaction (HER) at the cathode and the urea oxidation reaction (UOR) or the oxygen evolution reaction (OER) at the anodes of urea–water or water electrolysis. The morphology and catalytic performance were investigated using a series of physical characterization and electrochemical tests. The results show that at an electrolysis current density of 100 mA cm−2, the anode potential of the MoP@NiCo-LDH/NF-20 electrode is 1.392 V (vs. RHE) for UOR, 233 mV less than that of an IrO2/NF electrode (1.625 V); and the cathode potential of the MoP@NiCo-LDH/NF-20 electrode is 0.255 V (vs. RHE) for HER, closest to that of IrO2/NF (170 mV). For the two-electrode electrolyser (MoP@NiCo-LDH/NF-20‖MoP@NiCo-LDH/NF-20), the cell voltage is as low as 1.405 V for urea–water electrolysis and 1.697 V for water electrolysis at a current density of 100 mA cm−2, even lower than those of a Pt/C/NF‖IrO2/NF cell. Moreover, after 20 hours of continuous electrolysis, the performance and morphology of the catalyst are almost unchanged, indicating that it has both high activity and stability. The results show that the developed MoP@NiCo-LDH/NF-20 is a promising bifunctional catalyst.
qas: question: What's the cathode?
question: What's the anode?
answers: answer_id: 228559
question_id: 66159
text: penta-graphene
question: What's the electrolyte?
context: Recently, the atomic-level thickness and large surface area of 2D materials are beneficial to the generation of carriers on the surface and separation of photogenerated carriers. Typically, in comparison to their 3D counterparts, 2D materials present extremely numerous active sites, high carrier mobility, and controllable interface, which offer a large number of advantages for catalysts, electronics, optoelectronics, etc. Among them, penta-type materials have been developed as a series of novel 2D materials. For instance, Yang et al. reported a novel 2D material, penta-Pt2N4, with a large direct band gap, high carrier mobility and high Young's modulus, suggesting numerous potential applications in nanoelectronics. Xiao et al. found that penta-graphene shows desirable electrochemical performance and it may be a potential candidate for Li/Na-ion battery anodes. However, bulk pyrite-SiAs2 has been synthesized under high pressure and validated as a semiconductor decades ago. Meanwhile, this type of pyrite structure can form a 2D penta structure after cleaving the plane, but 2D penta-SiAs2 has not yet been explored.
qas: question: What's the electrolyte?
context: Flexible supercapacitors are playing an increasingly important role in energy storage due to their viability in flexible intelligent wearable electronic devices, which require irregular power supply at different discharge rates. Two-dimensional (2D) nanomaterials have gradually become potential electrode materials for flexible supercapacitors due to their atomic thickness and electrochemically active surface, especially since they allow the development of binder-free flexible electrodes with improved capacitance. 2D materials can provide slit-shaped ion diffusion channels that enable fast movement of electrolyte ions into the electrode bulk.
qas: question: What's the electrolyte?
context: To study the electrolyte reduction processes resulting in SEI formation, cyclic voltammetry (CV) was performed systematically as a function of added HF concentration (as-received, +10, +100, and +500 ppm) and voltage sweep rate. Fig. 5 shows a series of CV scans measured at 5 mV s−1 in electrolytes with varying concentrations of HF. The peak at ∼2 V, indicated by the dashed line, results from the electrocatalytic reduction of HF to form LiF (reaction (2)). The additional peak at higher potential in the as-received electrolyte may be attributed to either PF6− or POF3 reduction. The slight shift in peak position to higher potentials (from 1.9 to 2 V) with increasing HF concentration is consistent with the report by Strmcnik et al. Solutions with more HF exhibit higher peak currents and increased capacity going into SEI formation. If a uniform film of LiF alone were fully passivating the copper surface, this would be achieved at a specific capacity as further HF reduction would be prevented by the passivation, and increased HF in the electrolyte would not lead to increased SEI capacity. However, this data suggests that LiF alone does not passivate the copper surface at these HF concentrations and scan rates because increased HF concentration in the electrolyte results in a corresponding increase in the capacity of the HF reduction peak. Passivating LiF films can be formed under different conditions, however, namely at slower scan rates and on smoother single-crystalline substrates. We rationalize that HF reduction is limited by the availability of HF at this interface, which in turn determines the amount of LiF that is formed in the initial SEI.
qas: question: What's the electrolyte?
context: We report, for the first time, that DPPT-TT is a lower performance channel material compared to P3HT and PBTTT. For DPPT-TT, the ON current (∼−1.0 μA), VON value (∼0.63 V), and transconductance (0.012 mS), are far below the performance of P3HT and PBTTT. Still, the addition of DBSA to the electrolyte is effective in enhancing its performance and results in a significant increase in the ON current and decrease in the operation voltage. The positive effect of adding DBSA to the electrolyte extends not only to DPPT-TT but also PBTTT, where it appears to have an even stronger effect.
qas: question: What's the electrolyte?
context: Inspired by the remarkably active Mn4CaO5 clusters for water oxidation, Mn3O4 with high-concentration and stable Mn3+ has, therefore, been extensively researched as an efficient electrocatalyst for OER. In the spinel structure Mn2+Mn23+O4, Mn existed as Mn2+ and Mn3+; here, Mn3+ occupied the octahedral site and Mn2+ ion occupied the tetrahedral site. The coexistence of Mn2+ and Mn3+ offers excellent OER activity. Therefore, numerous studies have focused on exploring high-quality Mn3O4 catalysts for efficient electrocatalytic OER. Further, earlier studies have also demonstrated that Mn3O4 electrocatalysts are highly active toward OER in neutral and alkaline media. For example, Nam's group reported the fabrication of 4 and 8 nm Mn3O4 nanoparticles (Fig. 13a and b). Owing to the enlarged surface area and improved electrical conductivity, the as-obtained Mn3O4 nanoparticles showed apparently higher OER activity in comparison with other Mn oxides (Fig. 13c). Remarkably, the optimized 8 nm Mn3O4 nanoparticles that were loaded on the surface of NFs exhibited outstanding OER activity with overpotential of only 395 mV at 10 mA cm−2 under neutral conditions, which was much superior to those of Fe-, Co-, and Ni-based oxides. As demonstrated by Maruthapandian et al., Mn3O4 catalysts also showed excellent electrocatalytic performance for OER in basic solutions (Fig. 13d and e). In particular, they demonstrated the synthesis of Ni-doped Mn3O4 catalysts, which showed significantly enhanced OER electrocatalytic activity in 1 M KOH solution with overpotential of 283 mV at 10 mA cm−2 (Fig. 13f). Further, a mechanistic study revealed that the largely improved OER performance could be ascribed to the enhanced adsorption/desorption of hydroxide and oxygen atoms, boosting the formation of metal oxyhydroxide/hydroperoxo. Moreover, the efficient electron charge between the electrolyte and Mn3O4 and enlarged electrochemical surface active sites facilitated the promotion of electrocatalytic OER performance.
qas: question: What's the electrolyte?
answers: answer_id: 103679
question_id: 66160
text: 1 M potassium sulfate
context: Typically, the working electrodes were fabricated by mixing 10 wt% of the binder polytetrafluoroethylene (PTFE), 10 wt% conductive agent (Super-P-Li) and 80 wt% of active materials (MnO2, K0.296Mn0.926O2 and active carbon). Ethanol was used to make the above materials into a slurry and Ni foam was employed as the current collector to coat the slurry with a mass loading of around 3 mg cm−2. Each electrode was dried for 6 hours in the oven and finally subjected to a pressure of 10 MPa. Electrochemical tests were performed on a three-electrode system with 1 M potassium sulfate as the electrolyte with the HgO/Hg as the reference electrode and Pt foil as the counter electrode. The CHI 660E Electrochemical Workstation was used to test the galvanostatic charge–discharge (GCD) and cyclic voltammetry (CV). The Zahner IM6 Electrochemical Workstation was employed to measure the electrochemical impedance spectroscopy (EIS). The LAND battery system was used to test the cycling life.
qas: question: What's the electrolyte?
answers: answer_id: 103677
question_id: 66160
text: LLZTO 
context: In summary, the mechanism of Li dendrite formation in LLZTO was discussed in terms of energy band structure as well as defect states, and was investigated by REELS, SPEM, and Nano Q-DLTS. The experimental results corroborate that the higher defect densities at the GBs lower the SBH by 0.5 eV and makes metallic Li atoms propagate along the GBs in LLZTO. As a way of preventing Li dendrite formation in LLZTO, bandgap engineering by the laser annealing treatment was proposed. Amorphous LLZTO and Li2O2 layers formed after laser annealing hinder the Li dendrite formation by blocking the electron injection. The hybrid electrolyte cell comprising the laser-treated LLZTO sample exhibits significant improvement in cycling performance and stability. Consequently, the laser annealing treatment on the LLZTO electrolytes can direct the development of materials engineering toward high-performance solid-state batteries. Furthermore, the analytical approach in this study highlights the importance of the electronic band structure of LLZTO for its stability and provides the direction to study various solid electrolyte materials.
qas: question: What's the electrolyte?
answers: answer_id: 103683
question_id: 66160
text: carbonate-based
context: Anthraquinone-1,5-disulfonic acid disodium salt (1,5-AQDS, 1a) was first proposed for potassium batteries by Xu et al. In a carbonate-based electrolyte, the authors achieved the reversible capacity per material mass (Qm) of 95 mA h g−1 at 0.1C (13 mA g−1), and after a hundred cycles the capacity was 78 mA h g−1.
qas: question: What's the electrolyte?
context: The high-rate performance of 3Mg/Mg2Sn was mainly attributed to a low RCT. EIS spectra revealed that the RCT in 3Mg/Mg2Sn is significantly smaller than that in Mg2Sn (Fig. S5†). While the RCT values in 3Mg/Mg2Sn varied between 77 and 140 Ω, those in Mg2Sn varied in the range of 500–2500 Ω. This was not surprising because the apparent RCT is dependent on the surface area that is accessible by electrolytes. The larger BET surface area and micro-to-macroporosity of 3Mg/Mg2Sn, therefore, resulted in a significantly low RCT, which eventually contributed to the high-rate performance.
qas: question: What's the cathode?
question: What's the electrolyte?
answers: answer_id: 103690
question_id: 66160
text: mixed Al/Li-ion
context: For electrochromic applications, the device shows rapid, self-powered color switching and multicolor display (color switching from light yellow to transparent, light red, dark green, dark blue and black, corresponding to the combination of the different states of the two films). As an energy storage device, the as-assembled device provides three different open-circuit potentials with an overall areal capacity of up to 933 mA h m−2. Meanwhile, the utilization of the mixed Al/Li-ion electrolyte and the addition of PEDOT:PSS into the inorganic materials greatly promote the cycle stability of the cathode films. Such a new design of the EES device with multicolor display, large charge capacity and high cycle stability can be promising for future color switching/energy storage applications, which may also provide new insights into the design of multifunctional devices.
qas: question: What's the electrolyte?
context: Polylactic acid (PLA) is a type of bio-based, renewable, and biodegradable material made by starch raw materials from renewable plant resources. The physical properties of small molecules of poly(ethylene glycol) (PEG)–PLA were analyzed with FAMD simulations with the COMPASS forcefield, and the mechanical properties of large-chain PLC were studied using CGMD with the MARTINI force field. Recent research focused on designing PLA composites through MD simulations to improve the inherently weak mechanical properties of PLA. For example, MD simulations of the microstructures of PLA–o-carboxymethyl chitosan (CMC) composites showed that introducing CMC enhanced the stiffness of PLA, and the analysis of the interfacial properties of PLA–graphene composites yielded a scheme to design nanocomposites with high strength and toughness. Other than characterizing the molecular phenomena of polymers, the swelling behavior of cross-linked hydrogels in poor solvents were also studied using a CG model, where counterions were considered explicitly. Similar swelling conformations were found for charged cross-linked hydrogels as single polyelectrolyte chains. Furthermore, the effects of various experimentally-controlled parameters were systematically investigated to provide insight into the rational design of hydrogels with desired conformations and properties.
qas: question: What's the electrolyte?
context: Currently, metal or metal compounds have been widely investigated as electrode materials for SCs owing to their high theoretical specific capacity. Nevertheless, the inferior electronic conductivity, poor ion-diffusion and instability (metal) of such materials still hinder their practical applications. Massive research studies have indicated that coupling with a high electronic conductivity carbon matrix is a fascinating method to address the above problems. Electrospun 1D CNFs possess high mechanical strength, excellent electronic conductivity, and a high surface area, making them a promising substrate/host for metal or metal compounds. Furthermore, CNFs within CNF-based composites offer a number of advantages: (i) the ability to effectively inhibit the agglomeration of active materials, (ii) substantial enhancement of the electrochemically active surface area, (iii) the ability to maintain the integrity of the composite electrode, (iv) more effective electrolyte permeation and ion/electron transport and (v) an enlarged voltage window. As show in Table 2, the metal compounds showed enhanced cycling performance and rate capability when hybridized with highly compatible CNFs as electrode materials in SCs. Herein, based on diverse extensively studied active materials (i.e. metals, metal oxides, metal sulfides, metal nitrides, metal phosphides, metal carbides, other nanocarbons, metal hydroxides, MOFs, and conducting polymers), different types of CNF-based composites are divided and discussed.