Thermal Stability and Outgassing Behaviors of High‐nickel Cathodes in Lithium‐ion Batteries

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(43)

Опубликована: Июнь 9, 2023

Abstract LiNiO 2 ‐based high‐nickel layered oxide cathodes are regarded as promising cathode materials for high‐energy‐density automotive lithium batteries. Most of the attention thus far has been paid towards addressing their surface and structural instability issues brought by increase Ni content (>90 %) with an aim to enhance cycle stability. However, poor safety performance remains intractable problem commercialization in market, yet it not received appropriate attention. In this review, we focus on gas generation thermal degradation behaviors high‐Ni cathodes, which critical factors determining overall performance. A comprehensive overview mechanisms outgassing runaway reactions is presented analyzed from a chemistry perspective. Finally, discuss challenges insights into developing robust, safe cathodes.

Язык: Английский

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The predicted persistence of cobalt in lithium-ion batteries

Nature Energy, Год журнала: 2022, Номер 7(12), С. 1132 - 1143

Опубликована: Окт. 20, 2022

Язык: Английский

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Toward a Mechanistic Model of Solid–Electrolyte Interphase Formation and Evolution in Lithium-Ion Batteries

ACS Energy Letters, Год журнала: 2022, Номер 7(4), С. 1446 - 1453

Опубликована: Март 22, 2022

The formation of passivation films by interfacial reactions, though critical for applications ranging from advanced alloys to electrochemical energy storage, is often poorly understood. In this work, we explore the an exemplar film, solid–electrolyte interphase (SEI), which responsible stabilizing lithium-ion batteries. Using stochastic simulations based on quantum chemical calculations and data-driven reaction networks, directly model competition between SEI products at a mechanistic level first time. Our results recover Peled-like separation into inorganic organic domains resulting rich reactive without fitting parameters experimental inputs. By conducting accelerated elevated temperature, track evolution, confirming postulated reduction lithium ethylene monocarbonate dilithium H2. These findings furnish fundamental insights dynamics illustrate path forward toward predictive understanding passivation.

Язык: Английский

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Elementary Decomposition Mechanisms of Lithium Hexafluorophosphate in Battery Electrolytes and Interphases

ACS Energy Letters, Год журнала: 2022, Номер 8(1), С. 347 - 355

Опубликована: Дек. 5, 2022

Electrolyte decomposition constitutes an outstanding challenge to long-life Li-ion batteries (LIBs) as well emergent energy storage technologies, contributing protection via solid electrolyte interphase (SEI) formation and irreversible capacity loss over a battery’s life. Major strides have been made understand the breakdown of common LIB solvents; however, salt mechanisms remain elusive. In this work, we use density functional theory explain lithium hexafluorophosphate (LiPF6) under SEI conditions. Our results suggest that LiPF6 forms POF3 primarily through rapid chemical reactions with Li2CO3, while hydrolysis should be kinetically limited at moderate temperatures. We further identify selectivity in proposed autocatalysis POF3, finding preferentially reacts highly anionic oxygens. These provide means design LIBs, indicating reactivity may controlled by varying abundance or distribution inorganic carbonate species limiting transport PF6– SEI.

Язык: Английский

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Face to Face at the Cathode Electrolyte Interphase: From Interface Features to Interphase Formation and Dynamics

Advanced Materials Interfaces, Год журнала: 2022, Номер 9(8)

Опубликована: Янв. 2, 2022

Abstract Development of high‐performing lithium‐based batteries inevitably calls for a profound understanding and elucidation the reactivity at electrode–liquid electrolyte interface its impact on overall performance safety. The formation, composition, properties, mechanisms cathode interphase (CEI) formation function are still to large extent unknown most battery materials, whereas same is well considered solid negative electrodes in literature. In particular, high voltage regions > 4.3 V, oxidative stability limit liquid electrolytes reached new mechanisms, involving surface active material beside decomposition, contribute interfacial nature CEI. Focusing cell chemistries, this review aims highlight less understood decomposition chemistry, dictated by components, as in‐depth research physicochemical electrochemical properties CEI evolution positive electrode sub‐surfaces.

Язык: Английский

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Onset Potential for Electrolyte Oxidation and Ni-Rich Cathode Degradation in Lithium-Ion Batteries

ACS Energy Letters, Год журнала: 2022, Номер 7(10), С. 3524 - 3530

Опубликована: Сен. 22, 2022

High-capacity Ni-rich layered metal oxide cathodes are highly desirable to increase the energy density of lithium-ion batteries. However, these materials suffer from poor cycling performance, which is exacerbated by increased cell voltage. We demonstrate here detrimental effect ethylene carbonate (EC), a core component in conventional electrolytes, when NMC811 (LiNi0.8Mn0.1Co0.1O2) charged above 4.4 V vs Li/Li+-the onset potential for lattice oxygen release. Oxygen loss enhanced EC-containing electrolytes-compared EC-free-and correlates with more electrolyte oxidation/breakdown and cathode surface degradation, concurrently V. In contrast, NMC111 (LiNi0.33Mn0.33Co0.33O2), does not release up 4.6 V, shows similar extent degradation irrespective electrolyte. This work highlights incompatibility between EC-based electrolytes (more generally, that such as Li-/Mn-rich disordered rocksalt cathodes) motivates further on wider classes additives.

Язык: Английский

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Advancing to 4.6 V Review and Prospect in Developing High‐Energy‐Density LiCoO₂ Cathode for Lithium‐Ion Batteries

Small Methods, Год журнала: 2022, Номер 6(5)

Опубликована: Март 24, 2022

Abstract Layered LiCoO 2 (LCO) is one of the most important cathodes for portable electronic products at present and in foreseeable future. It becomes a continuous push to increase cutoff voltage LCO so that higher capacity can be achieved, example, 220 mAh g –1 4.6 V compared 175 4.45 V, which unfortunately accompanied by severe degradation due much‐aggravated side reactions irreversible phase transitions. Accordingly, strict control on essential combat inherent instability related high challenge their future applications. This review begins with discussion relationship between crystal structures electrochemical properties as well failure mechanisms V. Then, recent advances strategies are summarized focus both bulk structure surface properties. One closes this presenting outlook efforts LCO‐based lithium ion batteries (LIBs). hoped work draw clear map research status LCO, also shed light directions materials design energy LIBs.

Язык: Английский

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Oxygen hole formation controls stability in LiNiO2 cathodes

Joule, Год журнала: 2023, Номер 7(7), С. 1623 - 1640

Опубликована: Июль 1, 2023

Ni-rich lithium-ion cathode materials achieve both high voltages and capacities but are prone to structural instabilities oxygen loss. The origin of the instability lies in pronounced oxidation O during delithiation: for LiNiO2, NiO2, rock salt NiO, density functional theory dynamical mean-field calculations based on maximally localized Wannier functions yield a Ni charge state ca. +2, with varying between −2 (NiO), −1.5 (LiNiO2), −1 (NiO2). Calculated X-ray spectroscopy K K-edge spectra agree well experimental spectra. Using ab initio molecular dynamics simulations, we observe loss from (012) surface delithiated two O⋅− radicals combining form peroxide ion, ion being oxidized O2, leaving behind vacancies O2− ions. Preferential release 1O2 is dictated via singlet ground spin conservation.

Язык: Английский

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Assessing the Intrinsic Roles of Key Dopant Elements in High‐Nickel Layered Oxide Cathodes in Lithium‐Based Batteries

Advanced Energy Materials, Год журнала: 2023, Номер 13(12)

Опубликована: Фев. 13, 2023

Abstract A rational compositional design is critical for utilizing LiNiO 2 ‐based cathodes with Ni contents > 90% as promising next‐generation cathode materials. Unfortunately, the lack of a fundamental understanding intrinsic roles key elements, such cobalt, manganese, and aluminum, makes high‐Ni limited range dopants (<10%) particularly challenging. Here, 5% single‐element doped cathodes, viz., LiNi 0.95 Co 0.05 O , Mn Al along undoped (LNO), influences are systematically examined through control cutoff charge energy density common practice voltage. Comprehensive investigations into electrochemical properties, combined in‐depth analyses structural interfasial stabilities electrolyte decomposition pathways advanced characterizations, unveil following: i) role regulates or state‐of‐charge and, more critically, occurrence H2–H3 phase transition, which essentially dictates cyclability; ii) LNO can be stabilized well avoidance transition; iii) provides merits overall an optimized operating condition. This work guidance high‐energy‐density sheds light on challenges removing Co.

Язык: Английский

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Lithium‐based batteries, history, current status, challenges, and future perspectives

Battery energy, Год журнала: 2023, Номер 2(6)

Опубликована: Окт. 7, 2023

Abstract Currently, the main drivers for developing Li‐ion batteries efficient energy applications include density, cost, calendar life, and safety. The high energy/capacity anodes cathodes needed these are hindered by challenges like: (1) aging degradation; (2) improved safety; (3) material costs, (4) recyclability. present review begins summarising progress made from early Li‐metal anode‐based to current commercial batteries. Then discusses recent in studying various types of novel materials both anode cathode electrodes, as well electrolytes separator developed specifically battery operation. Battery management, handling, safety also discussed at length. Also, a consequence exponential growth production over last 10 years, identifies challenge dealing with ever‐increasing quantities spent further economic value metals like Co Ni contained within extremely large numbers produced date volumes that expected be manufactured next years. Thus, highlighting need develop effective recycling strategies reduce levels mining raw prevention harmful products entering environment through landfill disposal.

Язык: Английский

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