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Durham, Jessica L.

Publications and source records attributed to Durham, Jessica L..

Stabilized lithium metal oxide electrode material and method of preparation

A stabilized lithium metal oxide cathode material comprises microparticles of lithium metal oxide in which individual particles thereof a core of lithium metal oxide and a coating of a different lithium metal oxide surrounding the core. There is an interface layer between the cores and the coatings in which there are gradients of metal ions in the direction of coating to core. The materials are made by a three stage process involving coprecipitating precursor metal hydroxide core particles at a controlled pH; coprecipitating a different metal hydroxide coating on the particles without controlling the pH; and then calcining the resulting coated precursor particles with lithium hydroxide to form the stabilized lithium metal oxide material.

Lipson, Albert L.↗

Stabilized lithium metal oxide electrode material and method of preparation

A stabilized lithium metal oxide cathode material comprises microparticles of lithium metal oxide in which individual particles thereof a core of lithium metal oxide and a coating of a different lithium metal oxide surrounding the core. There is an interface layer between the cores and the coatings in which there are gradients of metal ions in the direction of coating to core. The materials are made by a three stage process involving coprecipitating precursor metal hydroxide core particles at a controlled pH; coprecipitating a different metal hydroxide coating on the particles without controlling the pH; and then calcining the resulting coated precursor particles with lithium hydroxide to form the stabilized lithium metal oxide material.

Lipson, Albert L.↗

Roadmap for a sustainable circular economy in lithium-ion and future battery technologies

Abstract The market dynamics, and their impact on a future circular economy for lithium-ion batteries (LIB), are presented in this roadmap, with safety as an integral consideration throughout the life cycle. At the point of end-of-life (EOL), there is a range of potential options—remanufacturing, reuse and recycling. Diagnostics play a significant role in evaluating the state-of-health and condition of batteries, and improvements to diagnostic techniques are evaluated. At present, manual disassembly dominates EOL disposal, however, given the volumes of future batteries that are to be anticipated, automated approaches to the dismantling of EOL battery packs will be key. The first stage in recycling after the removal of the cells is the initial cell-breaking or opening step. Approaches to this are reviewed, contrasting shredding and cell disassembly as two alternative approaches. Design for recycling is one approach that could assist in easier disassembly of cells, and new approaches to cell design that could enable the circular economy of LIBs are reviewed. After disassembly, subsequent separation of the black mass is performed before further concentration of components. There are a plethora of alternative approaches for recovering materials; this roadmap sets out the future directions for a range of approaches including pyrometallurgy, hydrometallurgy, short-loop, direct, and the biological recovery of LIB materials. Furthermore, anode, lithium, electrolyte, binder and plastics recovery are considered in order to maximise the proportion of materials recovered, minimise waste and point the way towards zero-waste recycling. The life-cycle implications of a circular economy are discussed considering the overall system of LIB recycling, and also directly investigating the different recycling methods. The legal and regulatory perspectives are also considered. Finally, with a view to the future, approaches for next-generation battery chemistries and recycling are evaluated, identifying gaps for research. This review takes the form of a series of short reviews, with each section written independently by a diverse international authorship of experts on the topic. Collectively, these reviews form a comprehensive picture of the current state of the art in LIB recycling, and how these technologies are expected to develop in the future.

25 ENERGY STORAGE↗

Process for preparing doped lithium lanthanum zirconium oxide

A process for preparing doped-lithium lanthanum zirconium oxide (doped-LLZO) is described herein. The method involves dry doping of a co-precipitated lanthanum zirconium oxide (LZO) precursor. Dry doping is a process in which a dry powdered dopant is ground and mixed with a pre-prepared co-precipitated LZO precursor and a lithium salt to provide a LLZO precursor composition, which is subsequently calcined to form a doped-LLZO. The process described herein comprises calcining a dry, powdered (e.g., micron, sub-micron or nano-powdered) mixture of a co-precipitated LZO precursor, a dopant salt or oxide, and a lithium salt under an oxygen-containing atmosphere at a temperature in the range of about 500 to about 1100° C., and recovering the doped-LLZO after calcining.

Durham, Jessica L.↗

Direct Recycling of Blended Cathode Materials by Froth Flotation

We report that direct Li-ion battery recycling involves separating cathode active materials in the solid phase while preserving their electrochemical performance. To reuse the recycled ones in new batteries, it is necessary to separate individual cathode components, which would typically occur prior to the rejuvenation and any compositional reformulation processes. Herein, a froth flotation process is developed to separate pristine lithium nickel-manganese-cobalt oxide (LiNi 0.333 Mn 0.333 Co 0.333 O 2 , NMC111) and lithium manganese oxide (LMO) materials. The flotation results show that with multiple stages of the separation processes, a satisfactory separation is achieved with 95% grade or above of NMC111 in the froth product and 95% grade of LMO in the tailing product. The electrochemistry results show that the flotation chemicals have negligible impact on the electrochemical performance of recycled active materials, whereas the NMC111 exhibits a minor capacity fade after being in contact with deionized water at 2% solid concentration. An improvement in both the rate and cycling performance is achieved at 10% solid concentration or higher. It is found that there is little compositional and structural change to the aqueous recycled NMC111 powders. An effective and low-cost separation method for direct recycling mixed cathode compositions is demonstrated.

25 ENERGY STORAGE↗

Roles of Mn and Co in Ni-rich layered oxide cathodes synthesized utilizing a Taylor Vortex Reactor

It is reported that layered oxides, composed of nickel, manganese, and cobalt (NMC), are sought after as cathode materials which provide improved energy density, cycle life, and safety in commercial lithium ion batteries (LIBs). Increasing Ni contents higher than 80% can provide even higher practical discharge capacities >200 mAh/g and similar to ~4 V discharge potential vs Li/Li + , making them promising cathodes for next generation LIBs. However, rapid capacity fade during cycling and heat-related safety concerns are delaying their successful transition to industry. We report systematic performance optimization of LiNiO 2 , LiNi 0.9 Mn 0.1 O 2 , and LiNi 0.9 Co 0.1 O 2 high Ni layered oxide cathodes synthesized by utilizing a Taylor Vortex Reactor. Co-free LiNi 0.9 Mn 0.1 O 2 cathode showed 200 mAh/g highest discharge capacity at 0.1 C rate with 84% retention after 103 cycles at 0.3C rate while LiNi 0.9 Co 0.1 O 2 cathode showed higher initial but poor cycle life (225 mAh/g highest discharge capacity at 0.1C rate with only 56% capacity retention after 103 cycles at 0.3 C rate. Synchrotron based X-ray diffraction (SXRD), X-ray absorption spectroscopy (XAS) and focused ion beam (FIB) imaging of pristine and cycled cathodes after 103 cycles provided important information on degradation mechanism. The roles of Mn and Co on layered structure formation, charge balance, cationic mixing, and electrochemical performance were elucidated using the crystallographic information from XRD refinement and electronic state analysis from XAS providing valuable information to design future Ni-rich layered oxide cathodes.

25 ENERGY STORAGE↗

Stabilizing NMC 811 Li-Ion Battery Cathode through a Rapid Coprecipitation Process

Improving the capacity of LiNi x Mn y Co 1-x-y O 2 (NMC) by increasing the Ni content results in materials with poor cycling performance and reduced thermal stability. These problems can be alleviated by creating concentration gradients in the materials, but this requires more expensive batch processing. Herein, a simple process is described that can create a coating that penetrates into the precursor particles, creating unique gradients in the precursor material. The coated material demonstrates improved cycling performance and thermal stability as compared to uncoated materials. Additionally, rapid heating to simulate a thermal runaway event while observing these materials with X-rays gives a deeper understanding of how the coating affects the decomposition process.

25 ENERGY STORAGE↗

Facile and scalable dry surface doping technique to enhance the electrochemical performance of LiNi 0.64 Mn 0.2 Co 0.16 O 2 cathode materials

Lithium nickel manganese cobalt oxide (NMC) is one of the dominant cathode materials in lithium-ion batteries. In this study a simple, efficient and scalable surface doping technique is successfully demonstrated, which can be readily used in mass production of cathode materials. For the first time neodymium oxide (Nd 2 O 3 ) has been employed as the surface doping agent. The Nd-doped NMC shows greatly improved cycling and rate performance, and the enhanced cycling stability has been demonstrated in full pouch cells, with a 17.5% increase in capacity retention after 300 cycles. Fewer cracks have been observed in the doped NMC after cycling, and in situ X-ray diffraction reveals the suppressed lattice collapse by Nd doping. Greatly suppressed surface phase change has been confirmed by HR-TEM and EELS. The result suggests great promise in using this dry doping technique to enhance the electrochemical performance of NMC cathodes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Mitigating the Impact of Thermal Binder Removal for Direct Li-Ion Battery Recycling

Li-ion battery recycling will become critical to the management of end-of-life batteries from electric vehicles. Currently, it is a challenge to create a profitable recycling process, which is made more difficult by the reduction in cathode cobalt content. Maintenance of the cathode structure throughout the recycling process can yield increased revenues that may make recycling profitable. This method will require careful removal of the PVDF binder and carbon black, which can be achieved through thermal processing. Furthermore, it is necessary to mitigate the effects of the fluorine from the PVDF on the cathode material. Herein, we report a process that utilizes excess LiOH•H 2 O to react with this fluorine and thereby prevent lithium removal and doping of the cathode material. In addition, we demonstrate a one-step thermal process that can both remove the binder and relithiate the cathode material.

25 ENERGY STORAGE↗

Improving the Thermal Stability of NMC 622 Li-Ion Battery Cathodes through Doping During Coprecipitation

Increasing the Ni content of LiNi x MnyCo 1-x-y O 2 (NMC) cathodes can increase the capacity, but additional stability is needed to improve safety and longevity characteristics. In order to achieve this improved stability, Mg and Zr were added during the coprecipitation to uniformly dope the final cathode material. These dopants reduced the capacity of the material to some extent, depending on the concentration and calcination temperature. However, these dopants can impart substantial stabilization. It was found that the degree of stabilization is strongly dependent on the calcination temperature of the material. In addition, we used synchrotron X-ray diffraction during thermal breakdown to better understand why the different dopants impact the thermal stability and confirm the stabilization effects of the dopants.

25 ENERGY STORAGE↗