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Urfer, A.; Lawrance, G. A.; Swinkels, D. A. J.

doi:10.1023/a:1017512721635

Cited by 13 publications

(15 citation statements)

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“…In both instances we assume that the reference electrode potential, E ref , is constant throughout discharge. This assumption is supported by the data of Wruck 10 for the Zn electrode and Urfer et al 24 for the Hg/HgO electrode. In addition, in arriving at Eq.…”

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confidence: 58%

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Primary Alkaline Battery Cathodes A Three-Scale Model

Farrell

Please

McElwain

et al. 2000

J. Electrochem. Soc.

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A mathematical model for the galvanostatic discharge and recovery of porous, electrolytic manganese dioxide cathodes, similar to those found within primary alkaline batteries is presented. The phenomena associated with discharge are modeled over three distinct size scales, a cathodic (or macroscopic) scale, a porous manganese oxide particle (or microscopic) scale, and a manganese oxide crystal (or submicroscopic) scale. The physical and chemical coupling between these size scales is included in the model. In addition, the model explicitly accounts for the graphite phase within the cathode. The effects that manganese oxide particle size and proton diffusion have on cathodic discharge and the effects of intraparticle voids and microporous electrode structure are predicted using the model.

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confidence: 58%

“…In the solid phase of each particle, the movement of electrons is governed by Ohm's law, namely i EMD ϭ Ϫ EMD ٌ EMD [24] where EMD (V) is the potential in the manganese oxide and EMD (S/cm) is the effective conductivity of the oxide phase. This conductivity is a function of the Mn 4ϩ concentration and in the present work is taken to be of the form…”

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confidence: 99%

Primary Alkaline Battery Cathodes A Three-Scale Model

Farrell

Please

McElwain

et al. 2000

J. Electrochem. Soc.

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“…Carbon black is noted to improve overall performance in MnO2 cathodes undergoing deep discharge by reducing the size of the product phase particles and enhancing overall electrode conductivity, at the cost of open circuit potential. (30,31) As predicted, cells assembled with carbon black instead of graphite exhibited ∼200 mV lower open circuit potential, due to the interaction of the surface groups on the carbon black with the MnO2. However, the higher surface area of the amorphous carbon significantly enhances interdigitation of the conductive additives and active material, leading to a substantial improvement of the overall capacity of the full cell, increasing capacity from ∼280 to ∼360 mAh/g.…”

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confidence: 61%

Effect of Multiple Cation Electrolyte Mixtures on Rechargeable Zn–MnO₂ Alkaline Battery

et al. 2016

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A Bi2O3 in β-MnO2 composite cathode material has been synthesized using a simple hydrothermal method and cycled in a mixed KOH-LiOH electrolyte with a range of concentrations. We show that, at a KOH:LiOH molar ratio of 1:3, both proton insertion and lithium insertion occur, allowing access to a higher fraction of the theoretical capacity of the MnO2 while preventing the formation of ZnMn2O4. This enables a capacity of 360 mAh/g for over 60 cycles, with cycling limited more by anode properties than traditional cathodic failure mechanisms. The structural changes occurring during cycling are characterized using electron microscopy and in situ synchrotron energy-dispersive X-ray diffraction (EDXRD) techniques. This mixed electrolyte shows exceptional cyclability and capacity and can be used as a drop-in replacement for current alkaline batteries, potentially drastically improving their cycle life and creating a wide range of new applications for this energy storage technology.

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“…Additionally, we recognize that the Timrex KS-6 graphite (BET = 20 m 2 /g) used in this study has an order of magnitude larger surface area compared to ConocoPhillips G8 graphite (BET = 1.5-2 m 2 /g), which is optimized for Li-ion battery use and has a smooth surface coating. 22,23 Therefore, it is expected that SEI formation is enhanced on the anode in this study as there are more reaction sites for formation compared to commercial anodes. This also explains the significantly larger irreversible capacity loss measured within the first few cycles, ∼25% loss based on theoretical capacity.…”

Section: Resultsmentioning

confidence: 88%

Measuring Li⁺Inventory Losses in LiCoO₂/Graphite Cells Using Raman Microscopy

Snyder

Apblett

Grillet

et al. 2016

J. Electrochem. Soc.

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The contribution from loss of Li + inventory to capacity fade is described for slow rates (C/10) and long-term cycling (up to 80 cycles). It was found through electrochemical testing and ex-situ Raman analysis that at these slow rates, the entirety of capacity loss up to 80 cycles can be explained by loss of Li + inventory in the cell. The Raman spectrum of LiCoO 2 is sensitive to the state of lithiation and can therefore be leveraged to quantify the state of lithiation for individual particles. With these Raman derived estimates, the lithiation state of the cathode in the discharged state is compared to electrochemical data as a function of cycle number. High correlation is found between Raman quantifications of cycleable lithium and the capacity fade. Additionally, the linear relationship between discharge capacity and cell overpotential suggests that the loss of capacity stems from an impedance rise of the electrodes, which based on Li inventory losses, is caused by SEI formation and repair. Lithium ion batteries (LIB) provide the highest energy densities compared to other rechargeable battery types.1 For this reason, they are being pursued for usage in advanced applications such as electric vehicles and storage of intermittent renewable energies (solar, wind, etc.). Despite their promise, degradation caused by both chemical and physical mechanisms diminishes LIB performance. Chemically, formation of a solid electrolyte interphase (SEI) on the surface of both the graphite anode and the LiCoO 2 cathode accompanied by other side reactions between the electrolyte and the electrode surface 2 results in the loss of cycleable Li + and thus capacity. These surface films also increase electrode impedance, which can shorten the time for the cell to reach cutoff voltages and affect rate capability of the cell. 3,4 Capacity loss can also originate due to physical mechanisms. For example, stress may accumulate in electrode materials during lithiation and delithiation owing to the large volumetric alterations induced by these processes. 4,5 Volumetric expansion can be up to 10% in graphite and ∼1.6% in LiCoO 2 .6,7 Such expansion and the induced stress can, in turn, lead to fracturing of active particles, cracking and reforming of the SEI, and loss of contact among electrode components (i.e., active material, polymeric binder, and current collectors). 4 Taken together, these chemical and physical degradation mechanisms induce capacity fade with repeated cycling that curtail the lifetime of the battery.Beyond identification, it is necessary to assess the relative influence of individual mechanisms to the totality of capacity fade. 3,8,9 Specifically, comparisons between the relative impact of several mechanisms-primary active material loss (Li + inventory), secondary active material loss (LiCoO 2 and/or graphite), and increased internal cell resistance (caused by surface films)-remain the topic of continued investigation.3 Such effort is complicated by the dependence of these mechanisms to several parameters as it has been...

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Cited by 13 publications

References 1 publication

Primary Alkaline Battery Cathodes A Three-Scale Model

Primary Alkaline Battery Cathodes A Three-Scale Model

Effect of Multiple Cation Electrolyte Mixtures on Rechargeable Zn–MnO₂ Alkaline Battery

Measuring Li⁺Inventory Losses in LiCoO₂/Graphite Cells Using Raman Microscopy

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Untitled

Cited by 13 publications

References 1 publication

Primary Alkaline Battery Cathodes A Three-Scale Model

Primary Alkaline Battery Cathodes A Three-Scale Model

Effect of Multiple Cation Electrolyte Mixtures on Rechargeable Zn–MnO2 Alkaline Battery

Measuring Li+Inventory Losses in LiCoO2/Graphite Cells Using Raman Microscopy

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Product

Resources

About

Effect of Multiple Cation Electrolyte Mixtures on Rechargeable Zn–MnO₂ Alkaline Battery

Measuring Li⁺Inventory Losses in LiCoO₂/Graphite Cells Using Raman Microscopy