Lithium-ion batteries have become a widespread energy storage technology, and research continues towards improving battery properties. One route to increase electrode areal active material loading and decrease relative volume fractions of inactive components is to increase electrode thickness, but increasing thickness can impact mechanical stability for conventional composite electrodes. All active material (AAM) electrodes, including those in this work, can mitigate mechanical and transport limitations for very thick lithium-ion electrodes. Such electrodes are free of polymer binders and conductive additives, and processed by pressing electroactive material powder into a porous pellet followed by mild sintering to improve mechanical properties. This study investigated the processing of a more recent material processed into AAM electrodes, TiNb2O7, which has relatively high volumetric capacity among reported materials processed into AAM electrodes. The anode material was characterized in AAM electrodes where different processing temperatures were used, resulting in different titanium and niobium containing phases being present. This manuscript provides insights and electrochemical consequences for fabricating AAM electrodes with multicomponent oxide phases.
Thick sintered porous tellurium pellets are fabricated and evaluated as cathodes in lithium–tellurium batteries. These electrodes lack inactive binders and conductive additives and have very high areal capacity, which are important attributes for increasing cell energy density. More commonly tellurium in lithium–tellurium batteries is processed via melt impregnation into a conductive host. In contrast, herein, porous sintered electrodes comprising only tellurium material dramatically increase the areal active material loading to 150 mg cm−2compared to the typically reported <5 mg cm−2. A processing route is used on the tellurium powder to reduce the particle size and increase the electroactive area by a factor of 13. With the increased surface area, gravimetric capacity increased for the same current density and retention of capacity at increasing rates has even greater improvement. Thick all active material–sintered tellurium electrodes provide a route toward high volumetric energy density batteries, where the relatively high electronic conductivity of tellurium is expected to be beneficial due to the lack of conductive additives in the electrode system.
- NSF-PAR ID:
- 10402871
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Technology
- Volume:
- 11
- Issue:
- 6
- ISSN:
- 2194-4288
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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