batterydata/battery-device-data-qa huggingface dataset:
The electrochemical test of the Li–CO2 battery was performed by using a 2025 type coin cell with a hole (diameter of 1 cm) on the cathode side. As for the cathode preparation, SiC/RGO and polyvinylidene fluoride (PVDF) were blended in N,N-dimethylformamide with a mass ratio of 9:1 to obtain a slurry. The slurry was uniformly deposited on a circular carbon paper with a diameter of 1 cm, and then dried in a vacuum oven at 80 °C. The loading mass of the active material was about 0.5 mg for each pellet. Li foil was used as the anode, and a glass fiber was employed as the separator. 1 M LiTFSI dissolved in TEGDME was used as the electrolyte. The battery was assembled in an argon-filled glove box, and then installed into a self-made sealed quartz bottle. The chamber was repeatedly flushed with pure CO2 prior to the measurements to ensure that the gas in the bottle was pure CO2. Each measurement was performed after a 2 h open circuit potential step to ensure equilibrium in the cell. The electrochemical measurements were carried out using a LAND cycler (CT2001A) and an electrochemical workstation (CHI660D, Shanghai Chenhua). A 500 W Xe-lamp was used as the light source for the tests involving light assistance.

Question: What's the cathode?
Answer: SiC/RGO and polyvinylidene fluoride (PVDF)

Question: What's the anode?
Answer:  Li foil

Question: What's the electrolyte?
Answer: 1 M LiTFSI dissolved in TEGDME
Inspired by the superior properties of the DBHF fiber cathode, solid-state hybrid batteries were fabricated. As displayed in Fig. 7a and b, a sandwich-type hybrid Zn battery is fabricated based on the DBHF cathode, Zn nanosheets@carbon cloth anode and the gel electrolyte membrane (details in ESI S-4†). Firstly, the stability and flexibility of the fabricated solid state hybrid battery were investigated. As detected in Fig. 7e, good stability in various states, from flat to high degree of bending (Fig. 7g) was achieved during cycling at 2 mA cm−2. The charge/discharge profiles of the last cycle at each bending test (Fig. 7h) indicate the two sets of well-retained voltages corresponding to the redox reaction and ORR/OER processes with negligible shape change at different bending degrees. Therefore, the results demonstrate the good stability and excellent flexibility of the prepared hybrid battery. Next, the high-rate performance of the fabricated hybrid battery was investigated at a series of current densities from 2 to 10 mA cm−2. Good cycling stabilities were achieved at different current densities (Fig. 7f). The charge voltage gradually increases and the discharge voltage decreases with increased current densities. Even at a high current density of 10 mA cm−2, the two sets of charge/discharge voltages are well retained (Fig. 7i), demonstrating its superior high rate capability. Moreover, the flexible hybrid cell exhibits high stability and high efficiency during long-term cycling at the high current density of 6 mA cm−2 (Fig. 7j). After five thousand cycles, the flexible hybrid Zn battery achieves well-defined two-set charge/discharge profiles (Fig. 7k), which demonstrate its high stability and high efficiency. Combining the above results, the solid-state hybrid battery exhibits good stability, superior high rate capability and good flexibility in an air environment, where the Zn-ion battery and Zn–air battery work simultaneously.

Question: What's the cathode?
Answer:  DBHF fiber

Question: What's the anode?
Answer: Zn nanosheets@carbon

Question: What's the electrolyte?

Question: What's the cathode?
Answer: DBHF
Aiming to achieve higher energy batteries, researchers have started to revisit the LiNiO2 chemistry with hopes that knowledge obtained from NMC and NCA studies could be applied to LiNiO2 and resolve the issues that were identified decades ago. Furthermore, eliminating the use of cobalt can circumvent the issues surrounding Co such as high toxicity, high cost, and child labor abuse in mining. At the material level, the most popular strategy is the bulk cationic doping to enhance the electrochemical reversibility. With doping strategies, Co-free Ni-rich layered cathode materials are expected to deliver comparable battery performance to NMCs and NCAs. In addition, many studies have been performed on modulating the electrolyte composition to improve the electrode–electrolyte interphase for stabilizing the battery performance. The surface of LiNiO2-based materials is much more reactive than NMC and NCA materials owing to the extreme Ni3+/Ni4+ redox couple. Thus, revealing the origins of surface changes can better inform the advanced design of promising LiNiO2-based materials. At present, most studies rely on ex situ characterization methods to understand the surface degradation of cathode materials, for example, transition electron microscopy (TEM) based techniques for atomic scale structural and chemical analysis, as well as surface sensitive X-ray spectroscopy for ensemble-averaged measurements to probe surface chemical information. The surface sensitive probing techniques typically have low penetrating depths, which makes it difficult to study surface chemistry under practical battery operating environments. Noticeably, the chemical and structural information on the particle surface may be influenced by a range of experimental conditions, including but not limited to, human exhalation, sample storage, and sample preparation during material surface analysis. This can skew observations found in characterization analysis, surface doping, and electrochemical protocol. Therefore, to characterize the surface of LiNiO2 properly, one must understand how the experimental conditions influence overall surface and interfacial chemistries.

Question: What's the cathode?
Answer: Co-free Ni-rich

Question: What's the electrolyte?
The critical property of anode materials is coulombic efficiency. CE at the first cycle is particularly significant since it usually leads to the highest capacity losses due to SEI formation and other irreversible reduction processes. As shown in Chart 5e, a relatively high 1st cycle CE (>60%) is observed for carboxylates, carbonyls 10 and 21, as well as for P30, P31, and P32. For other materials, as well as for some inorganic benchmarks (carbons with a high surface area, phosphorous, FeS2), the CE is even lower. It should be noted that the CE depends not only on the material but also on the electrolyte composition. The tuning of the electrolyte is rarely reported. Some studies indicate that using ether-based electrolytes, such as KPF6 in DME, improves the CE. More attention should be paid to the electrolyte optimization, particularly for the materials that showed low CE with the carbonate-based solutions.

Question: What's the anode?

Question: What's the electrolyte?
Answer: KPF6 in DME
In this study, three types of electrolytes were prepared for investigation: 1.0 M LiPF6 in ethylene carbonate/diethyl carbonate (EC/DEC, 1:1 v/v, marked as LPE-EC), 1.0 M LiPF6 in propylene carbonate/diethyl carbonate (PC/DEC, 1:1 v/v, marked as LPE-PC), and 1.0 M LiPF6 in PC/DEC (1:1 v/v, with 0.005 M LiBOB, marked as LPE-PC–LiBOB). All the electrolytes were prepared in an argon-filled glove box.

Question: What's the electrolyte?
Answer: 1.0 M LiPF6 in ethylene carbonate/diethyl carbonate

Question: What's the electrolyte?
Answer: 1.0 M LiPF6 in ethylene carbonate/diethyl carbonate (EC/DEC, 1:1 v/v, marked as LPE-EC), 1.0 M LiPF6 in propylene carbonate/diethyl carbonate (PC/DEC, 1:1 v/v, marked as LPE-PC), and 1.0 M LiPF6 in PC/DEC (1:1 v/v, with 0.005 M LiBOB, marked as LPE-PC–LiBOB)
For dual-ion batteries, increasing Qm is also principally possible by, for example, increasing the concentration of redox-active nitrogen atoms in aromatic amines. For such optimized materials, where most of the active units are involved, it is expected that the operation potentials will get higher at least for conjugated structures because polymers with a high positive charge at the backbone are harder to oxidize. It will therefore be important to develop electrolytes for potassium batteries, which are tolerant to high voltages, or to elaborate protective coatings at the cathode surface. Certain progress in the development of high-voltage potassium battery electrolytes has already been achieved.

Question: What's the cathode?

Question: What's the electrolyte?
To address the challenges facing Li–S batteries, considerable efforts have been made to develop sulfur-based cathode composite materials, modify separators, protect Li anodes, and use conductive interlayers and/or novel electrolyte additives (Fig. 1b). These approaches have all yielded certain encouraging results. However, the above strategies often have variable effects on the performance of Li–S batteries, owing to the specificity and interdependency of the S8–Li2Sn–Li2S (solid–liquid–solid) multistage transformation. For example, the conductive interlayer introduced between the separator and cathode suppresses the migration of LiPSs, which also offers additional electron pathways that cover the top surface of the cathode. This performance enhances the use of active materials and reduces random deposition of Li2S on the surface of the Li anode, thereby restraining dendrite formation and improving the anode stability to a certain degree.

Question: What's the cathode?
Answer: sulfur-based

Question: What's the anode?
Answer: Li

Question: What's the electrolyte?

Question: What's the anode?
Answer: Li
In summary, we developed a formation method of a Li protective artificial SEI layer to form a LiF and polymeric composite protection layer directly on lithium metal foil using the electrochemical reaction between the Li and the sacrificial PTFE film by using roll-pressing. The roll-press process is facile, cost-effective, eco-friendly and a mass and large-area scalable process. The composite protection layer composed of a LiF-rich layer and polyene/unsaturated fluoropolymer rich layer could significantly improve the electrochemical properties of LMBs. The LiF@Po protection layer provides a stable interface between the Li metal and the electrolyte, enabling improved Li plating/stripping behavior and ultra-long cycling stability in both the Li‖Li symmetric cell and Li‖LCO/Li‖NCM full cells. In particular, the full cell with the NCM-811 cathode and LiF@Po–Li anode exhibits reasonable electrochemical performance even with transition metal dissolution. The material design strategies presented here could provide important avenues for forming an artificial SEI layer in various applications not only in Li metal systems but also in other metal systems including sodium and potassium.

Question: What's the cathode?
Answer: NCM-811

Question: What's the anode?
Answer: LiF@Po–Li

Question: What's the electrolyte?
To evaluate the performances of 2D GeP nanosheet-based photodetectors at an exact wavelength, selected wavelengths of lights (350, 365, 380, 400, 475, 550 and 650 nm) were employed (Fig. 4) in 0.1, 0.5 and 1 M KOH electrolytes. It is clear to see that the photocurrent density values are greatly smaller than the values under simulated light because of inferior light irradiation. The photocurrent density and photoresponsivity show a similar trend to the results in a simulated light state. Notably, it is also shown that such 2D GeP nanosheet-based photodetectors exhibit a higher sensitivity at a short wavelength range, especially at 350, 365 and 380 nm (Fig. 4c, f and i) and the highest photoresponsivity is 187.5 μA W−1 at 380 nm wavelength, 0.6 V applied bias potential and in 0.5 M KOH electrolyte. The above photo-response results at different wavelengths are in strong agreement with the UV-Vis absorption spectrum in Fig. 1g. Such results demonstrate great potential for high-performance UV-Vis photodetector application.

Question: What's the electrolyte?
Answer: 0.1, 0.5 and 1 M KOH

Question: What's the electrolyte?
Answer: 0.5 M KOH
The detailed preparation processes of positive electrodes can be found in previous work. The mass loading of active material was ∼3.0 mg cm−2 for positive electrodes. In 2032-type half cells, lithium foil was used as the anode. Pre-lithiated MCMB was utilized as the negative electrode in full cells. The electrolyte was 1 M LiPF6 dissolved in mixed solvents of DMC and EC (7:3 by volume). Galvanostatic charge–discharge was conducted using a LAND tester (CT-2001A). All electrochemical testing was performed at room temperature (25 °C).

Question: What's the anode?
Answer: lithium foil

Question: What's the electrolyte?
Answer: 1 M LiPF6
The stretchability was also tested through stretching the developed spring ssZIBs. First, a spring solid-state battery was prepared by sealing the cathode, anode, and CNF–PAM hydrogel electrolyte in a spring-type plastic tube. As shown in Fig. 3i, a digital clock was powered by the developed blue spring solid-state battery. As shown by the figure in Fig. 3j and k and the video provided in ESI III and IV,† the spring solid-state battery still worked well under repeated tension and contraction. This demonstrates the robust stability, high stretchability and flexibility of our ssZIBs.

Question: What's the cathode?

Question: What's the anode?

Question: What's the electrolyte?
Answer: CNF–PAM hydrogel
For the first time, DBHF nanofibers are constructed as flexible cathodes for HZBs. The formation mechanism of the DBHF structure is probed and the relationships between the synthetic conditions and the structures of the products are carefully investigated. Moreover, the HZBs are fabricated based on the DBHF cathode, Zn nanosheet@carbon cloth anode and a polymer electrolyte. Benefitting from the unique structure, the hybrid battery achieves high energy/power density and long-term cycling stability. Moreover, the high flexibility and “air-charging” capability make it a good uninterrupted power source for flexible electronics in different environments (Fig. 1h and i).

Question: What's the cathode?
Answer: DBHF nanofibers

Question: What's the anode?
Answer: Zn nanosheet@carbon

Question: What's the electrolyte?

Question: What's the cathode?
Answer: DBHF
Among ceramic electrolytes, the garnet-structured oxide Li7La3Zr2O12 (LLZO) has attracted attention as a core material of next-generation batteries (post-LIBs) because it exhibits excellent chemical/electrochemical stability against Li metals and has large electrochemical stability window. In particular, LLZO offers significant advantages in inhibiting Li dendrite formation because it is a single-ion conductor (transference number ∼1), has a high shear modulus (∼60 GPa) and stable interface with Li metals. Despite these intrinsic advantages, LLZO still has the problem of short circuit formation caused by Li propagation through LLZO particularly under high current densities. The penetration of Li through the polycrystalline LLZO electrolyte has been recently interpreted in terms of wettability of Li metals on LLZO, mechanical failure induced by stresses during Li plating that caused flaws on the LLZO surface, high electronic conductivity and a high interfacial resistance as well as non-uniform current distribution by lithium carbonate (Li2CO3) formed on the LLZO surface by the reaction between water vapor, carbon dioxide and LLZO in ambient air. Li propagation is known to occur via preferential plating at the grain boundaries (GBs), and the interface property of Li metal and LLZO plays a critical role in Li penetration when a high current density is applied to the interfaces. Because of the impurities or defects that predominantly exist on the GBs, different energy states for reduction at GBs might lead to non-uniform distribution of Li plating and preferential propagation of Li ions through the GBs. However, the mechanism of Li dendrite formation is unclear and remains controversial. Here, we investigated the mechanism of Li dendrite formation for the crystalline Ta-doped LLZO (Li6.5La3Zr1.5Ta0.5O12, LLZTO) by examining their energy band structures and defect states using various analytical techniques including reflection electron energy loss spectroscopy (REELS), scanning photoelectron microscopy (SPEM), and nanoscale charge-based deep level transient spectroscopy (Nano Q-DLTS). The measurement results revealed that the metallic Li plating along the GBs originates from the plentiful defect states in the GBs, implying that the formation of Li dendrites can be avoided if a thin layer with a wide bandgap is coated on LLZTO grains. Based on these analytical measurements, we adopted the laser annealing of LLZTO as a bandgap engineering method to suppress the Li dendrite formation by forming a surface structure of amorphous LLZTO and Li2O2 with wide bandgaps, which can block the electron injection into the grain boundaries. In addition, our electrochemical measurement results for the laser-treated LLZTO demonstrated that the stability and cycling performance were significantly improved. This study sheds light on the importance of electronic structure, in particular, defect states in developing ceramic solid electrolytes for Li metal batteries and the practicality of surface modification by laser treatment.

Question: What's the electrolyte?
Answer:  Li7La3Zr2O12 (LLZO)

Question: What's the electrolyte?
Answer: LLZO
The as-prepared polymer SP, Super P carbon and poly(vinylidene fluoride) (PVDF) binder with a mass ratio of 6/3/1 were added to a flask, and then dispersed in 1-methyl-2-pyrrolidinone (NMP) after being vigorously stirred for 10 h. The obtained slurry was coated on Cu foil, followed by drying at 100 °C in vacuo. The Cu foil was punched with a diameter of 14 mm as the anode electrode and the mass of SP was about 1.8 mg. A CR2032 coin-type cell was assembled in a glove box with SP as the working electrode, Celgard2400 polypropylene as the separator, lithium foil as the counter and reference electrode, and the prepared electrolyte consisted of a mixture of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and ethylene carbonate (EC) (DMC/EMC/EC = 5/2/3 v/v/v). The galvanostatic charge–discharge (GCD) and rate properties were determined by using a LAND battery test system at room temperature. After being pre-cycled at 0.2 C (20 mA h g−1) for three cycles, the battery was then tested at 1 C (100 mA h g−1) for 200 cycles. The cyclic voltammograms (CV) ranging from 0.01 V to 3 V were recorded with a CHI600E electrochemical working station with a scan rate of 0.1 mV s−1.

Question: What's the anode?
Answer: Cu foil

Question: What's the electrolyte?
Answer: a mixture of dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and ethylene carbonate (EC) (DMC/EMC/EC = 5/2/3 v/v/v)
In order to enhance the capacity and rate performance of the electrodes, Fan et al. used 2,6-AQDS 1b in combination with carbon nanotubes (CNTs) and a DME-based electrolyte. Reversible Qm was up to 174 mA h g−1, higher than the theoretical value. It was partially attributed to the contribution from CNTs (23 mA h g−1). The authors assembled a full cell, which had pre-potassiated graphite as an anode. The cell had a Qm of up to 87 mA h g−1 (per mass of AQDS) with an average discharge voltage of 1.1 V. At 500 mA g−1, the capacity retention of the full cell was 33% after 2500 cycles.

Question: What's the anode?
Answer: graphite

Question: What's the electrolyte?
Answer:  DME-based
Herein, a Li/LiV2(PO4)3 primary battery (Fig. 1a) with a long shelf life is proposed, which exhibits impressive electrochemical performances under high power densities and low-temperature conditions. It has been found that the corrosion of the Al current collector triggered by the organic radical cations generated from the electrochemical oxidation of EC at high potentials; and the detrimental reaction between LiV2(PO4)3 and electrolyte lead to the self-discharge of Li/LiV2(PO4)3 primary batteries. When EC was replaced by PC, the corrosion of the Al foil was alleviated. LiBOB was found to be conducive to increase the shelf life of the Li/LiV2(PO4)3 primary batteries as it formed a protective film on the surface of the cathode, which effectively alleviated the side reaction between LiV2(PO4)3 and the electrolyte. Most importantly, the Li/LiV2(PO4)3 primary batteries exhibited excellent performances at high charge/discharge rates (up to 50C) and even at temperatures as low as −40 °C.

Question: What's the cathode?

Question: What's the electrolyte?
The electrocatalytic application of HEA NPs in the selective CO2 reduction reaction (CO2RR) has also been reported recently. For example, Nellaiappan et al. reported quinary fcc-AuPtAgPdCu NPs as an efficient CO2RR electrocatalyst toward CH4 and C2H4 in the low overpotential region. The five elements in the quinary HEA NPs were homogeneously distributed, whose chemical environments adopt metallic characteristics determined by XPS analysis except for Cu; a small amount of Cu2+ content was observed. The quinary fcc-AuPtAgPdCu NPs obtained superior selectivity toward the CO2RR in the low overpotential region, that is, FEmethane = 38.2% and FEethylene = 29.5% at −0.9 VAg/AgCl (−0.3 VRHE) in a CO2-saturated 0.5 M K2SO4 electrolyte (FE: faradaic efficiency). Based on their DFT calculation, the excellent electrocatalytic activity toward the CO2RR has mainly originated from redox-active Cu content in AuPtAgPdCu, while other elements provide an additional synergy in the CO2RR. Also, the long-term stability of the catalyst was verified by a chronoamperometry test for 5 h in a CO2-saturated 0.5 M K2SO4 electrolyte.

Question: What's the electrolyte?
Answer: 0.5 M K2SO4

Question: What's the electrolyte?
Answer: CO2-saturated 0.5 M K2SO4
The Li3V2(PO4)3 (LVP) electrode slurry was prepared by mixing LVP, carbon black (Super P), and polyvinylidene fluoride (PVDF) in a weight ratio of 8:1:1 in N-methyl pyrrolidone (NMP); this slurry was coated on the Al foil followed by drying at 120 °C for 24 h. Then, the electrodes were cut into disks with a diameter of 14.0 mm and used for coin cell assembly. The mass loading of the LVP electrodes was 2.3–2.6 mg cm−2. The primary batteries (CR2016, coin-type cell) were assembled using the Li3V2(PO4)3 cathode, Celgard 2325 separator, electrolytes, and Li metal anode in an argon-filled glove box.

Question: What's the cathode?
Answer: Li3V2(PO4)3

Question: What's the anode?
Answer:  Li metal

Question: What's the electrolyte?
Fig. 4c shows the electrochemical impendence spectra of the full cell in the Na–H2O–urea–DMF electrolyte before cycling, after the first cycle and after 100 cycles. The Rs value of the battery in the Na–H2O–urea–DMF electrolyte, connected to the intercept on the real impedance axis at a high frequency in the EIS spectra, is relatively small and equal for the pristine state and after cycling, which suggests good ion diffusion in the electrolyte and good stability of the electrode materials before and after cycling. The Rct value represented the charge transfer resistance increase after the first cycle and after 100 cycles, indicating that a passivation layer may be formed on the NTP anode, which could be a significant factor in the improvement of the cycling performance of the NVP/NTP full cell. Moreover, the XRD patterns (Fig. S16†) and SEM images (Fig. S17†) of NVP/C and NTP/C before and after 500 cycles were recorded, respectively. The results indicate that the Na–H2O–urea–DMF electrolyte is conducive to achieving excellent stability of the NVP cathode. In addition, a NiHCF//NTP full cell displays 80% capacity retention after 2000 cycles at 2C rate (Fig. 4d).

Question: What's the cathode?
Answer: NVP

Question: What's the anode?
Answer: NTP

Question: What's the electrolyte?
Answer: Na–H2O–urea–DMF

Question: What's the electrolyte?
Answer: Na–H2O–urea–DMF