High performance asymmetric redox capacitor utilizing all oxidation states of vanadium
Bibliographic record
Abstract
Redox capacitors are promising hybrid energy storage systems able to deliver simultaneously high power and energy densities. Here, we present a novel design of an asymmetric hybrid device utilizing all four oxidation states of vanadium while using a vanadyl sulfate additive electrolyte, and two differently sized high-surface area graphene electrodes. The asymmetric design delivers high gravimetric capacities of 2555 and 1400 mAh g −1 at current densities of 5 and 20 A g −1 , respectively. The performance is significantly higher than that of a similar symmetric hybrid utilizing only three vanadium oxidation states. In terms of cycling stability, the superior performance is maintained for approximately 1100 charge and discharge cycles before capacity decay diminishes the advantages of the asymmetric design. Degradation studies indicate that the cycling performance losses can be attributed to shuttling of V 2+ ions between electrodes, and respective side-reactions which produce inactive vanadium oxides at the electrode. The electrochemistry in our novel asymmetric redox capacitor is similar to an all vanadium-redox flow battery (VRFB). Thus, this study can increase understanding of VRFB degradation mechanisms while proposing an alternative electrolyte with less complexity and maintenance requirements.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".