Influence of polymer binder structure on the properties of the graphite anode for lithium-ion batteries

Abstract

This paper discusses the impact of the structure and properties of three different polymer binders: polyvinylidene fluoride, sodium carboxymethyl cellulose and polyvinyl alcohol, on the electrochemical properties of spherical graphite anodes for Li-ion batteries. Electrochemical tests indicate that the nature of polyvinylidene fluoride contributes in decreasing the cycle life of graphite electrodes in contrast to effective water-based binders. This study demonstrates the possibility of manufacturing graphite-based electrode for Li-ion batteries that cycle longer and use water in the processing, instead of hazardous organic solvents like N-methylpyrrolidone, thereby improving performance, reducing cost and protecting the environment.

Functionalized polyvinyl alcohol nanofiber webs containing β–cyclodextrin/Vitamin C inclusion complex

“…Corresponding stretches on pure PVA spectrum were observed as C–O stretching vibration in the region of 1000–1250 cm −1 and CH 2 bonding at around 1400 cm −1 . In addition, the peak at around 2900 cm −1 on PVA spectrum was observed due to CH/CH 2 bonding [48]. When the FT-IR spectrum of β–CD was observed in Figures 3, the broad peak around the wavelength of 3300 cm −1 (OH stretching) and the characteristic peaks of β–CD were observed at around 1000–1200 cm −1 assigned to the coupled C−C/C−O stretching vibrations and the asymmetric stretching vibration of the C−O−C glycosidic bridge [49,50].…”

Functionalized polyvinyl alcohol nanofiber webs containing β–cyclodextrin/Vitamin C inclusion complex

“…Corresponding stretches on pure PVA spectrum were observed as C–O stretching vibration in the region of 1000–1250 cm −1 and CH 2 bonding at around 1400 cm −1 . In addition, the peak at around 2900 cm −1 on PVA spectrum was observed due to CH/CH 2 bonding [48]. When the FT-IR spectrum of β–CD was observed in Figures 3, the broad peak around the wavelength of 3300 cm −1 (OH stretching) and the characteristic peaks of β–CD were observed at around 1000–1200 cm −1 assigned to the coupled C−C/C−O stretching vibrations and the asymmetric stretching vibration of the C−O−C glycosidic bridge [49,50].…”

The Effect of Silicon Grade and Electrode Architecture on the Performance of Advanced Anodes for Next Generation Lithium-Ion Cells

“…It was shown with EDX measurements and SEM imaging that the spatial distribution and size of the components play a role in the successful application of electrodes in Li-ion cells; therefore, the slurry preparation will be revised, and the lateral distribution of the components will be characterized with laser induced breakdown spectroscopy. It was also shown [45][46][47][48] that the use of different binders (Na-CMC, SBR, PVDF) with different molecular weights and degrees of substitution plays a major role; hence, the amount and type of binder will also be amended. An overlithiation of the cathode or prelithiation of the anode may also increase the capacity of cells with silicon/graphite composite electrodes, which was shown in [49,50], and will also be examined in future studies.…”

Understanding inks for porous-electrode formation

“…Poly(vinylidene) fluoride (PVdF), carboxymehtyl cellulose (CMC), and polyvinyl alcohol (PVA) are common polymers used as binders in battery applications 30,31 and a proton conducting polymer (e.g., perfluorosulfonic acid (PFSA)) 32 or hydroxideconducting ionomer is used in catalyst layers. A good polymer for electrochemical applications is characterized by a high adhesion strength in order to avoid delamination and an ability to swell and uptake electrolyte for effective ionic transport 19 .…”

“…There have been significant efforts to optimize and innovate the polymer in terms of properties (conductivity), structure, molecular weight, durability, and cost. 19 In addition, recent research efforts include discerning the effect of the solvent on the structure and functional properties in electrode systems 31 . Specifically, the mobility of the polymer in a solvent, 40 the degree of chain entanglement in the solvent, 41 and the colloidal morphological form of the polymer 42 have all been identified as important properties for creating effective catalyst layers.…”

Functionalized polyvinyl alcohol nanofiber webs containing β–cyclodextrin/Vitamin C inclusion complex

“…Corresponding stretches on pure PVA spectrum were observed as C–O stretching vibration in the region of 1000–1250 cm −1 and CH 2 bonding at around 1400 cm −1 . In addition, the peak at around 2900 cm −1 on PVA spectrum was observed due to CH/CH 2 bonding [48]. When the FT-IR spectrum of β–CD was observed in Figures 3, the broad peak around the wavelength of 3300 cm −1 (OH stretching) and the characteristic peaks of β–CD were observed at around 1000–1200 cm −1 assigned to the coupled C−C/C−O stretching vibrations and the asymmetric stretching vibration of the C−O−C glycosidic bridge [49,50].…”

The Effect of Silicon Grade and Electrode Architecture on the Performance of Advanced Anodes for Next Generation Lithium-Ion Cells

“…It was shown with EDX measurements and SEM imaging that the spatial distribution and size of the components play a role in the successful application of electrodes in Li-ion cells; therefore, the slurry preparation will be revised, and the lateral distribution of the components will be characterized with laser induced breakdown spectroscopy. It was also shown [45][46][47][48] that the use of different binders (Na-CMC, SBR, PVDF) with different molecular weights and degrees of substitution plays a major role; hence, the amount and type of binder will also be amended. An overlithiation of the cathode or prelithiation of the anode may also increase the capacity of cells with silicon/graphite composite electrodes, which was shown in [49,50], and will also be examined in future studies.…”

Understanding inks for porous-electrode formation

“…Poly(vinylidene) fluoride (PVdF), carboxymehtyl cellulose (CMC), and polyvinyl alcohol (PVA) are common polymers used as binders in battery applications 30,31 and a proton conducting polymer (e.g., perfluorosulfonic acid (PFSA)) 32 or hydroxideconducting ionomer is used in catalyst layers. A good polymer for electrochemical applications is characterized by a high adhesion strength in order to avoid delamination and an ability to swell and uptake electrolyte for effective ionic transport 19 .…”

“…There have been significant efforts to optimize and innovate the polymer in terms of properties (conductivity), structure, molecular weight, durability, and cost. 19 In addition, recent research efforts include discerning the effect of the solvent on the structure and functional properties in electrode systems 31 . Specifically, the mobility of the polymer in a solvent, 40 the degree of chain entanglement in the solvent, 41 and the colloidal morphological form of the polymer 42 have all been identified as important properties for creating effective catalyst layers.…”

Functionalized polyvinyl alcohol nanofiber webs containing β–cyclodextrin/Vitamin C inclusion complex

“…Corresponding stretches on pure PVA spectrum were observed as C–O stretching vibration in the region of 1000–1250 cm −1 and CH 2 bonding at around 1400 cm −1 . In addition, the peak at around 2900 cm −1 on PVA spectrum was observed due to CH/CH 2 bonding [48]. When the FT-IR spectrum of β–CD was observed in Figures 3, the broad peak around the wavelength of 3300 cm −1 (OH stretching) and the characteristic peaks of β–CD were observed at around 1000–1200 cm −1 assigned to the coupled C−C/C−O stretching vibrations and the asymmetric stretching vibration of the C−O−C glycosidic bridge [49,50].…”

The Effect of Silicon Grade and Electrode Architecture on the Performance of Advanced Anodes for Next Generation Lithium-Ion Cells

“…It was shown with EDX measurements and SEM imaging that the spatial distribution and size of the components play a role in the successful application of electrodes in Li-ion cells; therefore, the slurry preparation will be revised, and the lateral distribution of the components will be characterized with laser induced breakdown spectroscopy. It was also shown [45][46][47][48] that the use of different binders (Na-CMC, SBR, PVDF) with different molecular weights and degrees of substitution plays a major role; hence, the amount and type of binder will also be amended. An overlithiation of the cathode or prelithiation of the anode may also increase the capacity of cells with silicon/graphite composite electrodes, which was shown in [49,50], and will also be examined in future studies.…”

Understanding inks for porous-electrode formation

“…Poly(vinylidene) fluoride (PVdF), carboxymehtyl cellulose (CMC), and polyvinyl alcohol (PVA) are common polymers used as binders in battery applications 30,31 and a proton conducting polymer (e.g., perfluorosulfonic acid (PFSA)) 32 or hydroxideconducting ionomer is used in catalyst layers. A good polymer for electrochemical applications is characterized by a high adhesion strength in order to avoid delamination and an ability to swell and uptake electrolyte for effective ionic transport 19 .…”

“…There have been significant efforts to optimize and innovate the polymer in terms of properties (conductivity), structure, molecular weight, durability, and cost. 19 In addition, recent research efforts include discerning the effect of the solvent on the structure and functional properties in electrode systems 31 . Specifically, the mobility of the polymer in a solvent, 40 the degree of chain entanglement in the solvent, 41 and the colloidal morphological form of the polymer 42 have all been identified as important properties for creating effective catalyst layers.…”