Ni-rich NCM-based positive electrode materials exhibit appealing properties in terms of high energy density and low cost. However, these suffer from different degradation effects, especially at their particle surface. Therefore, this work, tungsten oxide is evaluated as a protective inorganic coating layer on LiNi0.8Co0.1Mn0.1O2 (NCM-811) for lithium-ion battery (LIB) cells investigated regarding rate capability cycling stability under operation conditions. Using electrochemical impedance...

Abstract The increase of specific energy current Li ion batteries via further the cell voltage, for example, to 4.5 V is typically accompanied by a sudden and rapid capacity fade, known as “rollover” failure. This failure result dendrite formation triggered in course electrode cross‐talk, that is, dissolution transition metals (TMs) from cathode deposition on anode. It shown herein, elimination ethylene carbonate (EC) state‐of‐the‐art electrolyte, 1.0 m LiPF 6 3:7 mixture EC ethyl methyl...

Nickel-rich layered oxide materials (LiNixMnyCo1–x–yO2, x ≥ 0.8, LiNMC) attract great interest for application as positive electrode in lithium ion batteries (LIBs) due to high specific discharge capacities at moderate upper cutoff voltages below 4.4 V vs Li/Li+. However, the comparatively poor cycling stability well inferior safety characteristics prevent this material class from commercial so far. Against background, new electrolyte formulations including additives are a major prerequisite...

The decomposition of state-of-the-art lithium ion battery (LIB) electrolytes leads to a highly complex mixture during cell operation. Furthermore, thermal strain by e.g., fast charging can initiate the degradation and generate various compounds. correlation electrolyte products LIB performance fading over life-time is mainly unknown. electrochemical in comprising 1 m LiPF6 dissolved 13 C3 -labeled ethylene carbonate (EC) unlabeled diethyl investigated corresponding reaction pathways are...

Abstract Layered oxides, particularly including Li[Ni x Co y Mn z ]O 2 (NCM xyz ) materials, such as NCM523, are the most promising cathode materials for high‐energy lithium‐ion batteries (LIBs). One major strategy to increase energy density of LIBs is expand cell voltage (>4.3 V). However, high‐voltage NCM graphite full cells typically suffer from drastic capacity fading, often referred “rollover” failure. In this study, underlying degradation mechanisms responsible failure NCM523...

Compared to conventional poly-crystal NCM, single-crystal NCM reveals significantly improved particle stability and less electrode cross-talk, which not only suppresses rollover fading but also improves performance aspects the cycle life up 4.7 V.

Abstract Lithium ion battery cells operating at high‐voltage typically suffer from severe capacity fading, known as ‘rollover’ failure. Here, the beneficial impact of Li 2 CO 3 an electrolyte additive for state‐of‐the‐art carbonate‐based electrolytes, which significantly improves cycling performance NCM523 ∥ graphite full‐cells operated 4.5 V is elucidated. LIB using stored 20 °C (with or without additive) decay due to parasitic transition metal (TM) dissolution/deposition and subsequent...

Further increase in the specific energy/energy density of lithium ion batteries can be achieved via further charge cell voltage. However, an enhanced electrode cross-talk, i.e., transition metal (TM) dissolution from cathode and deposition on anode, drastically limits cycle life, even leading to rollover failure. In this work, commonly used film-forming electrolyte additives vinylene carbonate (VC), fluoroethylene (FEC), difluorophosphate (LiDFP) are thoroughly evaluated regarding their...

Abstract NCM523 || graphite lithium ion cells operated at 4.5 V are prone to an early “rollover” failure, due electrode cross‐talk, that is, transition metal (TM = Mn, Ni, and Co) dissolution from deposition graphite, subsequent formation of Li dendrites, and, in the worst case, generation (micro‐)short‐circuits by dendrites growing cathode. Here, impact different separators on high‐voltage performance is elucidated focusing separators’ structural properties (e.g., membrane vs fiber) their...

Layered oxides, such as Li[Ni0.5Co0.2Mn0.3]O2 (NCM523), are promising cathode materials for operation at a high voltage, i.e., high-energy lithium-ion batteries. The instability-reasoned transition metal dissolution remains major challenge, which initiates electrode cross-talk, alteration of the solid electrolyte interphase, and enhanced Li-metal dendrite formation graphite anode, consequently leading to rollover failure. In this work, relevant impacts on failure mechanism highlighted. For...

Abstract High‐voltage Li ion batteries are compromised by lower cycle life due to enhanced degradation of cathode material, for example LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523). Crucial part is the initiated electrode crosstalk, that transition metal (TM) dissolution from and subsequent deposition on anode, as it forces formation high surface area lithium, capacity losses risk dendrite penetration, finally leading an abrupt end‐of‐life (=rollover failure). Hence, suppression this failure cascade...

The further increase of practically usable specific energies in lithium ion batteries (LIBs) can be realized by minimizing the capacity losses, e.g., via electrolyte additives. However, interpretation research results additive effects on performance is challenging, because even for identical materials and conditions different are observed, rendering validity, evaluation, comparison additives difficult. In this work, we show that such ambiguity significantly influenced quality used benchmark...

The specific energy/energy density of state-of-the-art (SOTA) Li-ion batteries can be increased by raising the upper charge voltage. However, instability SOTA cathodes (i. e., LiNiy Cox Mny O2 ; x+y+z=1; NCM) triggers electrode crosstalk through enhanced transition metal (TM) dissolution and contributes to severe capacity fade; in worst case, a sudden death ("roll-over failure"). Lithium difluorophosphate (LiDFP) as electrolyte additive is able boost high voltage performance scavenging...

In order to further increase the energy density of lithium ion batteries (LIBs), it is utmost importance develop advanced electrode materials in combination with suitable electrolytes, which deliver either higher capacities and/or can be operated at high cell voltage sufficient cycling stability. Here, we introduce (1H-imidazol-1-yl)(morpholino)methanone (MUI) as a cathode electrolyte interphase (CEI) forming additive for LiNi1/3Co1/3Mn1/3O2 (NMC111) || graphite cells up 4.6 V. The addition...

Abstract The decomposition of state‐of‐the‐art lithium ion battery (LIB) electrolytes leads to a highly complex mixture during cell operation. Furthermore, thermal strain by e.g., fast charging can initiate the degradation and generate various compounds. correlation electrolyte products LIB performance fading over life‐time is mainly unknown. electrochemical in comprising 1 m LiPF 6 dissolved 13 C 3 ‐labeled ethylene carbonate (EC) unlabeled diethyl investigated corresponding reaction...

Li/Mn‐rich layered oxide (LMR) cathode active materials offer remarkably high specific discharge capacity (>250 mAh g −1 ) from both cationic and anionic redox. The latter necessitates harsh charging conditions to potentials (>4.5 V vs Li|Li + ), which is accompanied by lattice oxygen release, phase transformation, voltage fade, transition metal ( TM dissolution. In cells with graphite anode, dissolution particularly detrimental as it initiates electrode crosstalk. Lithium...

The high specific capacity of Li-rich layered oxides up to 300 mAh g−1 renders them a promising class positive electrode materials for energy lithium ion batteries (LIBs). However, this material suffers from poor retention, voltage fade and structural degradation. degradation phenomena include phase transformation particle cracking during operation take place in the bulk as well active material's surface. In work, we demonstrate straightforward approach surface modification...

The ultra-short pulse laser has attracted attention as an advanced tool for functionalizing surface topography, since it high accuracy and results in little damage. In a previous study, some innovative patterns were introduced on cemented carbide surfaces, such dimples, which are commonly used oil reservoirs bearings. is not only related to the inherent features of laser, but also machining processes. Within this context, study aims investigate influence parameters (i.e., number study)...

Compaction under oscillatory shear and low normal pressure is an alternative method for mechanical deliquoring of compressible filter cakes. After the proof concept on a laboratory scale, this article deals with application process to existing continuous vacuum belt filter. For purpose, modular device was developed vibration compaction indexing horizontal (HVBF). It shown that industrially relevant material HVBF reduces initial residual moisture 39.9% after cake formation by up 10.5 percent...

Honing mostly describes the last step in production stage and is a machining process that produces precise elements regarding form, geometry surface quality. Process control crucial point order to meet these high-quality demands. A new approach further improve this could be predict quality based on data machine learning algorithms. In paper, method of random forests (RF) employed dimensional characteristics honed bores. was collected during test series.