Quantification of PF5 and POF3 from Side Reactions of LiPF6 in Li-Ion Batteries

Solchenbach, Sophie; Metzger, Michael; Egawa, Masamitsu; Beyer, Hans; Gasteiger, Hubert A.

doi:10.1149/2.0481813jes

Cited by 142 publications

(198 citation statements)

References 46 publications

(126 reference statements)

Supporting

Mentioning

173

Contrasting

Order By: Relevance

“…[ 21 ] also figure out the mechanism of EC reduction which provides the CO 2 and CO gaseous products. This is because, due to its higher electron affinity nature than linear carbonates (DEC and EMC), EC solvent undergoes electrochemical reduction reaction for SEI formation [ 22,23 ] , suggesting that the evolution of gases in batteries with in EC based electrolytes preferentially associated with EC decomposition. Scheme shows the possible electrochemical interfacial reduction pathways of EC solvent on the anode surface, mainly responsible for the evolution of CO 2 , CO and C 2 H 4 reductive gases at the Cu current collector.…”

Section: Resultsmentioning

confidence: 99%

Decoupling Interfacial Reactions at Anode and Cathode by Combining Online Electrochemical Mass Spectroscopy with Anode‐Free Li‐Metal Battery

Shitaw

Yang

Jiang

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

It is essential to decouple the interfacial reactions taking place at the anode and cathode in rechargeable batteries. However, due to the reactive nature of Li, it is challenging to use Li‐metal batteries (LMBs) protocol to decouple the interfacial reactions. The by‐products from the anode or cathode become mixed in Li/NMC111 cells, which make decoupling interfacial reactions difficult. Here, reactions at electrodes are successfully decoupled and demystified using a protocol combining anode‐free LMB (AFLMB) with online electrochemical mass spectroscopy. LiPF6 in ethylene carbonate (EC)/diethyl carbonate (DEC) and EC/ethyl methyl carbonate (1:1 v/v%) electrolytes are used to compare interfacial reactions in Li/NMC111 and Cu/NMC111 cells. In Cu/NMC111, the evolution of CO2, CO, and C2H4 gases at the initial stage of first charging is due to interfacial reactions at Cu surface due to solid–electrolyte‐interphase formation. However, the evolution of CO2 and CO gases at high voltage in the entire cycles is associated with chemical and/or electrochemical electrolyte oxidation at the cathode. This work paves a new concept to decouple interfacial reactions at electrodes for developing electrochemically stable electrolytes to improve the performance with the long‐cycling life of AFLMBs and LMBs.

show abstract

Section: Resultsmentioning

confidence: 99%

Decoupling Interfacial Reactions at Anode and Cathode by Combining Online Electrochemical Mass Spectroscopy with Anode‐Free Li‐Metal Battery

Shitaw

Yang

Jiang

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…22,24 The electrolyte with 1000 ppm water exhibited a more dramatic decrease in water content than that with 100 ppm water (Figure S1). Previous studies have proposed a series of several decomposition reactions for LiPF 6 as follows [Reactions (1)‐(3)]: [25–29]

true LiPF_{6} \vec{\leftarrow} LiF + PF_{5}

true PF_{5} + normalH_{2} normalO \to POF_{3} + 2 HF

true POF_{3} + normalH_{2} normalO \to HPO_{2} normalF_{2} + HF

…”

Section: Resultsmentioning

confidence: 99%

Effects of Film Formation on the Electrodeposition of Lithium

et al. 2020

View full text Add to dashboard Cite

Metallic lithium is the most popular anode material used in next-generation secondary batteries to achieve high energy densities. However, inhomogeneous deposition is a serious issue that must be addressed for large-scale implementation. Previous studies have highlighted that a surface film formed during the early stages of deposition may have an effect on deposition morphology. Lithium fluoride (LiF) is one of the main components in this surface film, and is thought to play an important role in the subsequent metallic lithium deposition. This study investigated the electrodeposition of lithium using 1.0 mol dm À 3 LiPF 6 /propylene carbonate (PC) with and without trace amounts of water. The correlation between the morphology of the deposited metallic lithium and surface film formation during galvanostatic deposition was investigated. The morphology of the deposited lithium metal was dependent on the elapsed time after adding water to the electrolyte. X-ray photoelectron spectroscopy and electrochemical quartz crystal microbalance analyses of the surface film confirmed that the amount of LiF in the film had a large effect on the morphology of the deposited metallic lithium. This study provides a basic understanding of lithium metal deposition and can guide improvements in electrolyte design for battery manufacturing.

show abstract

“…They both lead to the formation of low valence transition metal oxides assisted by the loss of oxygen, leading to cations whose salts are more soluble in liquid electrolytes than those composed of high valence transition metal ions are. The oxygen assisted solvent decomposition [(e.g., C 3 H 4 O 3 (EC) + [O] →CO 2 + CO + 2H 2 O)] results in the formation of H 2 O, which, in turn, hydrolyzes the salt (LiPF 6 ↔ LiF + PF 5 ) in the electrolyte solution with the formation of HF (LiPF 6 + H 2 O → POF 3 + 2HF + LiF; POF 3 + H 2 O → HF + HPO 2 F 2 ) [102]. This, in turn, attacks the metal oxide, which results in the formation of slightly more soluble MF 2 salts and H 2 O.…”

Section: Transition Metal-ion Dissolution and Anode-cathode Dialoguementioning

confidence: 99%

Degradation and Aging Routes of Ni-Rich Cathode Based Li-Ion Batteries

et al. 2020

View full text Add to dashboard Cite

Driven by the increasing plea for greener transportation and efficient integration of renewable energy sources, Ni-rich metal layered oxides, namely NMC, Li [Ni1−x−yCoyMnz] O2 (x + y ≤ 0.4), and NCA, Li [Ni1−x−yCoxAly] O2, cathode materials have garnered huge attention for the development of Next-Generation lithium-ion batteries (LIBs). The impetus behind such huge celebrity includes their higher capacity and cost effectiveness when compared to the-state-of-the-art LiCoO2 (LCO) and other low Ni content NMC versions. However, despite all the beneficial attributes, the large-scale deployment of Ni-rich NMC based LIBs poses a technical challenge due to less stability of the cathode/electrolyte interphase (CEI) and diverse degradation processes that are associated with electrolyte decomposition, transition metal cation dissolution, cation–mixing, oxygen release reaction etc. Here, the potential degradation routes, recent efforts and enabling strategies for mitigating the core challenges of Ni-rich NMC cathode materials are presented and assessed. In the end, the review shed light on the perspectives for the future research directions of Ni-rich cathode materials.

show abstract

Quantification of PF₅ and POF₃ from Side Reactions of LiPF₆ in Li-Ion Batteries

Cited by 142 publications

References 46 publications

Decoupling Interfacial Reactions at Anode and Cathode by Combining Online Electrochemical Mass Spectroscopy with Anode‐Free Li‐Metal Battery

Decoupling Interfacial Reactions at Anode and Cathode by Combining Online Electrochemical Mass Spectroscopy with Anode‐Free Li‐Metal Battery

Effects of Film Formation on the Electrodeposition of Lithium

Degradation and Aging Routes of Ni-Rich Cathode Based Li-Ion Batteries

Contact Info

Product

Resources

About