Dear Leonardo,

slurry preparation can be a tricky process and higly depends on the active material used, coating technique and the purpose of the electrode.

For example, PVDF is widely used as a binder for lithium-ion battery electrodes, however, it does not work so well with materials which are changing their volumes during charge/discharge processes, like sillicon (CMC works a lot better with those and it is more eco-friendly since you can prepare the slurry in aqueous media).

When it comes to slurry composition, for laboratory work, most of the works which I stumbled upon had 10% wt. of the binders used, as it provides enough binding to reduce the electrode pulverization during testing. However, for industrial applications the inactive masses in the electrodes (binder and conductive additives) need to be reduced to provide as much active mass in the electrode as possible, hence the optimization is required.

The casting techniques have also big impact on the electrode loadings. Usually, with doctor blade you can not reach more than a few mg/cm2, which is fine for a laboratory purposes (higher loadings can hinder the transport properties of both electrons and ions in the electrode). For the industrial applications however, different coating techniques are used, which provides electrodes with higher loadings (over a dozen mg/cm2), which at the same time produce electrodes capable of good ionic and electronic transport.

So, as an answer to your question, if you want to be thorough, an optimization for the slurry preparation should be done. However, you could easily aim for a composition, for example 80:10:10 wt. active mass : binder : conductive carbon with electrode loading of ca. 2-3 mg/cm2 to obtain reproducable results of your electrochemical experiments.

Best regards,

MK.

Dear Leonardo,

slurry preparation can be a tricky process and higly depends on the active material used, coating technique and the purpose of the electrode.

For example, PVDF is widely used as a binder for lithium-ion battery electrodes, however, it does not work so well with materials which are changing their volumes during charge/discharge processes, like sillicon (CMC works a lot better with those and it is more eco-friendly since you can prepare the slurry in aqueous media).

When it comes to slurry composition, for laboratory work, most of the works which I stumbled upon had 10% wt. of the binders used, as it provides enough binding to reduce the electrode pulverization during testing. However, for industrial applications the inactive masses in the electrodes (binder and conductive additives) need to be reduced to provide as much active mass in the electrode as possible, hence the optimization is required.

The casting techniques have also big impact on the electrode loadings. Usually, with doctor blade you can not reach more than a few mg/cm2, which is fine for a laboratory purposes (higher loadings can hinder the transport properties of both electrons and ions in the electrode). For the industrial applications however, different coating techniques are used, which provides electrodes with higher loadings (over a dozen mg/cm2), which at the same time produce electrodes capable of good ionic and electronic transport.

So, as an answer to your question, if you want to be thorough, an optimization for the slurry preparation should be done. However, you could easily aim for a composition, for example 80:10:10 wt. active mass : binder : conductive carbon with electrode loading of ca. 2-3 mg/cm2 to obtain reproducable results of your electrochemical experiments.

Best regards,

MK.

Michal Krajewski Thank you very much Michal, your answer is very useful and I will try as you said, I'll come back to you when I have something interesting.

Zahilia Caban Huertas

Post slurry preparation treatment(s) are, also, critical, such as the coating conditions[1] and methods[2] for more efficient[3] electrodes' coatings that improve (Lithium-ion battery) electrodes' operation.

1. https://www.researchgate.net/post/which_drying_shows_better_results_in_li-ion_battery

2. Pretreatment compositions and methods for coating a battery electrode https://patents.google.com/patent/WO2014150050A1/en http://www.freepatentsonline.com/9273399.html

3. Treatment for improved conductivity of collector-electrode interface in laminated lithium-ion rechargeable batteries http://www.freepatentsonline.com/5840371.html