HIGH-THROUGHPUT ELECTROCHEMICAL CHARACTERIZATION APPARATUS AND SYSTEM AND METHODS FOR USING THE SAME (iEdison No. 0685901-23-0011)
The invention relates to a design of a high-throughput (HPT) electrochemical characterization system (can be used as electrochemical screening platforms or multi-channel reactors) and its applications in redox flow batteries or other energy storage and conversion systems. The HTP electrochemical characterization system includes an array of holes for holding liquid samples (a), a bottom electrode part for counter electrode function (b), a top electrode part for working electrode and reference electrode function (c), a top electrode holder part for grouping the electrodes and integrating with robotic arm (d), and a bottom electrode holder part for size matching with deck layouts of the commercial available robotic platforms (such as the size of microtiter plates) and heating or cooling function (e).
Hybrid Energy Storage System Utilizing Redox Active Organic Compounds
Redox flow batteries (RFB) have attracted considerable interest due to their ability to store large amounts of power and energy. Non-aqueous energy storage systems that utilize at least some aspects of RFB systems are attractive because they can offer an expansion of the operating potential window, which can improve on the system energy and power densities. One example of such systems has a separator separating first and second electrodes. The first electrode includes a first current collector and volume containing a first active material. The second electrode includes a second current collector and volume containing a second active material. During operation, the first source provides a flow of first active material to the first volume. The first active material includes a redox active organic compound dissolved in a non-aqueous, liquid electrolyte and the second active material includes a redox active metal.
ELECTRIC POWER SYSTEMS, CONTROL SYSTEMS AND ASSOCIATED OPERATIONAL METHODS (iEdison No. 0685901-22-0033)
Distributed control architecture to engage end-use loads (GFAs) as a flexible operating resource in primary frequency resource(Grid connected and islanded) This disclosure contains multiple parts: 1) The use of GFA devices to improve primary frequency response. This is essentially load shedding during transients to prevent system collapse. A paper was published in 2018 using this concept to support networked microgrid operations, but it used static setpoints. 2) The use of a distributed control architecture, e.g. OpenFMB, to enable the updating of GFA setpoints to better align with current system conditions. Specifically, the setpoints that are appropriate for grid connected operations are not ideal for an islanded microgrids and may be again different for networked microgrid operations. This update would be on the pub/sub system and would only need to be updated when there are significant changes in system conditions. 3) Determining the appropriate setpoints for each GFA based on current system conditions. The current work is examining the determination of set point values based on the resources available to support primary frequency support, i.e., spinning reserve and fast frequency regulation from grid-forming inverters. Combining these three concepts is the entire idea. GFA devices are deployed on the system as part of normal installation. During normal grid connected system transients the GFAs can respond as was envisioned in the original GFA work. When parts of the system are islanded as one or more microgrids, the OpenFMB system collects information to determine the status of how DERs available to support primary frequency response. For systems with a lower level of resource, "more aggressive" GFA set points are selected. For stronger systems the set points are "less aggressive". The goal is to engage GFAs when needed to stabilize microgrid operations, but not to shed excessive load when necessary. A example of this would be the transition from a system with a large amount of solar PV and grid-following inverters to one with more batteries and grid-forming inverters, i.e. a microgrid going from day to night. When there is a high penetration of grid-following inverters the system will be 'weaker" and it will be desirable for the GFA to operate sooner during a transient. But when there are more grid-forming batteries such aggressive load shedding is not necessary and should be avoided. This concept adaptively changes them to reflect current system conditions.
CARBON BASED SURFACE TREATMENT ON SUBSTRATES TO IMPROVE WETTABILITY (iEdison No. 0685901-23-0141)
The invention disclosed herein is a carbon-based surface treatment and method of application that, when applied and heat-treated properly, confers excellent sodium wetting properties to a substrate. Examples of substrates include metals, glass, or ceramics, with a focus on sodium-ion conducting ceramics such as the sodium beta-alumina solid electrolyte (BASE) that is commonly used for various types of sodium batteries. Other examples could include other sodium ion conductors such as NaSICON. The surface treatment is in the form of a slurry or suspension of carbon-black, dispersed in a solvent, which may include an organic solvent, water, or a mixture of these. Additionally, co-solvents may be appropriate to optimize various properties of the suspension, such as dispersion of carbon-black, rheological properties, evaporation rate, wetting on the substrate of choice, etc. Further, a surfactant or detergent may also be added, with the goal of maintaining dispersion of the carbon-black and wetting on the substrate of choice. Finally, a binder may be added, which is intended to modify rheology, facilitate stiction of the wetting layer to the substrate after application, and provide mechanical adhesion and strength to the carbon-black layer.
Jarosite for Lithium Extraction
Jarosite is used to extract lithium from aqueous solutions. Given the inherent magnetic properties of Jarosite coupled with Li adsorption capacity, we envision a simpler and economical way to extract Li from aqueous environments. Jarosite is a generic term for an isostructural family of compounds of form AM3(OH)6(SO4)2, (where A+= Na, K, Rb, NH4, H3O, Ag, T and M3+= Fe, Cr, V), in particular has demonstrated reasonable properties for Li-ion batteries and unique lithium inclusion behaviors. Often the product of acid mine drainage and acid sulfate soil environments, jarosite is mostly restricted to surficial, acidified environment. The crystal structure consists of octahedral sheets decorated by sulfate tetrahedra with the cations residing between the octahedral - tetrahedral layers. Bridging hydroxyls connect adjacent metal octahedra. Interestingly, in the octahedral sheets the M3+ions occupy nodes of a triangular lattice with specific magnetic properties. We synthesized and characterized ammonia jarosite with a chemical formula of (NH4)Fe3(SO4)2(OH)6.Based on the ICP-OES data, the Jarosite material adsorbs ~30 mg of Li per gram of Jarosite after magnetic isolation in an aqueous environment at pH 10.
Juvenile Eel and Lamprey Acoustic Transmitter
ALUMINUM-ETHER-BASED COMPOSITION FOR BATTERIES AND AMBIENT TEMPERATURE ALUMINUM DEPOSITION (iEdison No. 0685901-22-0051)
We invented and demonstrated a novel electrolyte formulation comprised of dialkyl ethers (R1-O-R2, R: hydrocarbon functional groups) and aluminum chloride (AlCl3) that enables efficient, room-temperature electrochemical reduction of Al3+ to metallic aluminum (i.e., electrodeposition) and highly reversible oxidative stripping of metal to Al3+ ions (i.e., galvanic dissolution). The chemical formula of our electrolyte solution can be represented by nAlCl3 : mR1-O-R2 (0.1 ≤ m/n ≤ 5). The dialkyl ether (R1-O-R2) systems include widely available industrial solvents such as dipropyl ether (DPE) and dibutyl ether (DBE). At room temperature (~20 ºC) mixing of DPE or DBE (Lewis base) with AlCl3 (Lewis acid) forms yellowish solutions with high concentrations of Al3+ (up to 7.3 M). This unique electrolyte formulation enables highly efficient and reversible electrochemical processes (both electrodeposition and dissolution) and hence can be considered as a potential candidate for (i) high temperature Al coating in industrial processes, (ii) rechargeable aluminum-based batteries. Our novel electrolyte formulation is based on improving the rates of desolvation and resolvation steps during electrochemical processes by suppressing electrostatic interactions of multivalent Al3+ ions via weakly coordinating ethereal based solvents. The DPE/AlCl3 and DBE/AlCl3 electrolyte solutions demonstrate highly reversible Al plating/stripping at room temperature with low overpotential of - 0.2 V vs. Al/Al3+(Figure 1). The electrochemical performance of dialkyl ether-based electrolytes is more efficient and reversible compared to widely used electrolyte systems, such as ionic liquid based solvents reported in literature. Figure 1. Cyclic voltammograms of Pt electrode with the electrolyte solution of (A) AlCl3:DPE and (B) AlCl3:DBE at 1:1.2 (molar ratio) at 0.25 mV s-1 between - 0.8 - 1.5 V vs Al/Al3+. Highly efficient Al plating and stripping behavior is observed.
SUBSTRATE MODIFICATION WITH CROSSLINKED BRANCHED POLYMER FOR USE IN BATTERIES (iEdison No. (iEdison No. 0685901-19-0015))
A new modification of graphitic carbon felt (GCF) as an electrode for all-vanadium redox flow batteries (VRBs) was developed with cross-linked polymer film which helps to improve long-term cycling ability of the cells. The polymer modification which causes the vanadium coordination effect with tertiary amine groups of the main chains avoids the severe oxidation and preserves the concentration of vanadium species during long-term redox cycling. Besides the ability of polymer films keeps the membrane surface clean without precipitation of vanadium compounds [e.g. vanadium (V) sulfate, V2(SO4)5 or vanadium (IV) oxide sulfate, VOSO4] arising at high SOC which causes increasing temperature due to the electrostatic attraction between the ionized amine groups and SO42- ions. This is a good way to keep the internal resistance stable. The schematic illustrations of typical VRB system and with polyethyleneimine cross-linked with glutaraldehyde (PG) modified GCF electrodes are shown in Fig. 1. The PG modified GCF electrode was fabricated via stamping method with PEI (5 Wt.%, branched) and GA (1Wt.%) solutions. One-fifth of pristine GCF electrode (5*6 cm2) is immersed in each solution one by one two times. Then it is dried at 70ºC in vacuum for 5 hours and washed with de-ionized (DI) water several times. The PEIGA modified GCF (PGGCF) electrode dried overnight are used as positive and negative electrodes. This modification method has been proposed or demonstrated as proof of concepts for the new interphase between membrane and carbon electrode. Fig. 2 shows SEM images of (a, b and c) pristine GCF and (d, e and f) PGGCF electrodes with different magnifications. After PG coating, the string surface of PGGCF electrode became smooth with very thin polymer films like a spider web formed between carbon strings. Thus, the coating method is efficient way to get thin PG films on each string and between them. Based on SEM-EDX analysis, the polymer films are consisting of carbon, oxygen and nitrogen, as shown in Fig. 3. FT-IR spectrum of PGGCF electrode shows typical N-H and C-N stretching vibrations corresponding to PEI while the pristine GCF does not show them meaning that PEI was successfully coated on GCF electrode, as shown in Fig.4. The chemical reaction to form the PEIGA is shown in Fig. 5. The electrochemical performance of PGGCF and pristine GCF electrodes was evaluated in vanadium 3+ and 4+ solutions as negative and positive electrolytes (1.5M VOSO4 with 3.5M H2SO4), respectively with N115 membrane. The flow rate of electrolytes was 30ml/min and current was 50mA/cm2 operated in cut-off voltage range of 0.8-1.6V. As shown in Fig. 6, cycling stability of PGGCF cell with high cycling Coulombic efficiency (CE) is much better than GCF baseline cell for 100 cycles although the energy efficiency (EE) of PGGCF cell is lower than baseline cell due to their lower electrical conductivity and smaller surface area caused by polymer coating than pristine electrode. Fig. 7 shows the charge-discharge curves of the GCF baseline and PGGCF cells at 1st, 50th and 100th. The capacity decrease of baseline cell is observed in Fig. 6a with increasing overpotential and decreasing charge-discharge time as cycling proceeded, as shown in Fig. 7a while cycling ability of PGGCF cell is much more stable without severe increasing cell polarization. The poor cycling stability of baseline cell could be attributed to the concentration polarization of active species as cycling proceeded. Basically the concentration polarization results from vanadium crossover over prolonged cycling, but we found out different reason in this study. Based on ICP analysis for the electrolytes after 100 cycles, the oxidation of vanadium 4+ especially in positive electrolyte is considered as the main reason why the baseline has the concentration polarization. As a result, the amount of redox-active species (V4+) in positive side was significantly reduced and it becomes irreversible, as shown in Fig. 1a. Another reason we found is the precipitation of vanadium compounds on the membrane which may cause the decreasing proton conductivity and further increasing cell polarization. On the other hand, the concentration of V4+ in positive electrolyte of PGGCF cell after 100 cycles is almost same as the beginning of cell test meaning that PG modification helped to stabilize the oxidation state of V4+ for 100 cycles due to the vanadium coordination effect of PEI, as shown in Fig. 1b. To verify it, the cycled electrodes were analyzed by SEM-EDX showing that vanadium and sulfur atoms were detected in the polymer phase coated on the strings. A lot of tertiary amine groups on PEI backbone and their branches and ionized amine groups in the acidic electrolytes can coordinate vanadium and sulfur ions during the prolonged cycling. The effect of PG modification on membrane is shown in Fig. 9 showing digital photographs and SEM images of Nafion 115 membranes in the GCF baseline and PGGCF cells after 100 cycles. Theoretically the vanadium compounds are formed in vanadium electrolytes with different oxidation states [(a) 3+, (b) 4+ and (c) 5+] at high temperature (50ºC, stored for 2 weeks), as shown in Fig. 10. Therefore it is likely that vanadium compounds form at high SOC which causes increasing temperature in the cell especially during long-term cycling. In case of GCF baseline cell, the cycled membrane has lots of precipitates on the membrane surface while that of PGGCF cell has a clean surface without precipitates meaning that PG modification helps to avoid the precipitation which causes loosing redox-active species and increasing cell polarization as cycling proceeded.