Evaluation of Litdi Vs. LiPF<sub>6</sub> As Electrolytes in Contact with Several Cathodes and Anodes Materials
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Introduction Lithium-ion batteries supplying energy for electric cars and other devices are mostly based on electrolytes using LiPF 6 . The popularity of this salt is mostly due to the formation of a passivation layer with aluminum which made possible the utilization of this low cost material as current collector. In counter part, the thermal instability of LiPF 6 and it’s reactivity with moisture or protic species release a toxic, highly aggressive and undesirable gaz, HF. These major drawbacks have prompt researchers to replace LiPF 6 by salts with improved thermal, chemical and electrochemical properties. Unfortunately, most attempts to replace LiPF 6 with hydrolytically-stable salts have been unsuccessful because of Al corrosion [1] . Niedzicki et al. [2] showed that lithium 4,5-dicyano-2-(trifluoromethyl) imidazolide, commonly known as LiTDI could be an interesting substitute to LiPF 6 . They showed LiTDI didn’t corrode Al, which are consistent with our results, and have a thermal stability up to 250°C. It has a satisfactory conductivity thereby showing good performances with LiMn 2 O 4 at operational voltage range of 3 - 4.3 V. In the present study, we are interested to compare LiPF 6 and LiTDI. This research is in collaboration between Arkema [3] , which has developed an industrial process to synthesize battery grade LiTDI, and Hydro-Québec. Electrochemical performances of LiTDI in EC-DEC (3-7 v-v) was evaluated in coin cells (vs. Li) with four different cathodes materials: LiNi 1/3 Mn 1/3 Co 1/3 O 2 [3-4.2V], LiMn 2 O 4 [3–4.4V], LiFePO 4 [2-4V], LiCoO 2 [3- 4.2V] and also with two type of anodes materials: graphite [0-2.5V], and Li 4 Ti 5 O 12 [1.2-2.5V]. Results The results obtained in this study with LiTDI are very promising. For all materials tested, the LiTDI has showed good compatibilities and results are comparable with those of LiPF 6 . During the formation, we found that: - for positive electrodes, results with and without FEC gave similar discharged and irreversible capacities compared to LiPF 6 . - for graphite, results showed that it’s necessary to use FEC to form a thin and stable SEI (validated by SEM analysis). - for Li 4 Ti 5 O 12 , the use of additive increases the irreversible capacity. For all materials, the ragone analysis showed competitive results between LiTDI and LiPF 6 , as it can be seen in the Figure 1, for LiNi 1/3 Mn 1/3 Co 1/3 O 2 and LiMn 2 O 4 . Moreover, thanks to its high chemical stability, LiTDI has showed better performances than LiPF 6 in term of safety. Indeed, burning experiments have been realized and clearly showed a decrease of generated dangerous gas. Pouch cells batteries with LiNi 1/3 Mn 1/3 Co 1/3 O 2 /Li 4 Ti 5 O 12 [1.5-2.8V] were also assembled for long-term cycling (C/4-D/4) at 25°C and 40°C. At the moment at 130 cycles, the lost capacity is only 2% for each temperature, which demonstrate the good stability of LiTDI. References 1. K. Krause et al , J. Power Sources, 68 ( 1997 ), 320-325 2. Niedzicki et al. , J . Power Sources , 196 ( 2011 ), 8696-8700 3. G. Schmidt et al ., FR2982610.
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.
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 | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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 it