Direct coating of electrodes in silicon-dominant anode cells
Systems and methods are provided for high volume roll-to-roll direct coating of electrodes for silicon-dominant anode cells and may include applying a slurry to a current collector film, the slurry comprising silicon particles and a binder material; drying the slurry to form a precursor composite film; rolling the current collector film into a precursor composite roll; and applying a heat treatment to the precursor composite film and the current collector film in a nitrogen gas environment, wherein the heat treatment is configured for converting the precursor composite film to a pyrolyzed composite film. The heat treatment may include one or both of: applying the heat treatment to a roll comprising the precursor composite roll in whole; and applying the heat treatment to the current collector film as it is continuously fed from the precursor composite roll.
1. A method for electrode processing, the method comprising:
applying a slurry to a current collector film, the slurry comprising silicon particles and a binder material;
drying the slurry to form a precursor composite film;
rolling the current collector film into a precursor composite roll;
applying a heat treatment to the precursor composite film and the current collector film in an environment comprising nitrogen gas, wherein the heat treatment is configured for converting the precursor composite film to a pyrolyzed composite film; and
moving the precursor composite roll in whole through a heat treat oven during the heat treatment;
wherein the heat treatment comprises one or both of:
applying the heat treatment to a roll comprising the precursor composite roll in whole; and
applying the heat treatment to the current collector film as it is continuously fed from the precursor composite roll.
2. The method of claim 1 , comprising applying the heat treatment in a reducing atmosphere.
3. The method of claim 1 , comprising creating reducing atmosphere related conditions during the heat treatment, the reducing atmosphere related conditions comprising one or more of inert atmosphere, a vacuum, and a flowing of one or more reducing gases.
4. The method of claim 1 , comprising feeding the current collector with the coated precursor composite film, from the precursor composite roll, into a heat treat oven during the heat treatment.
5. The method of claim 1 , comprising rolling the current collector with the coated pyrolyzed composite film into a composite electrode roll.
6. The method of claim 1 , comprising applying the heat treatment separately in each of a plurality of temperature zones.
7. The method of claim 6 , comprising applying the heat treatment differently in at least two different ones of the plurality of temperature zones.
8. The method of claim 1 , wherein the heat treatment comprises passive cooling following pyrolysis.
9. The method of claim 1 , wherein the heat treatment comprises forced cooling following pyrolysis.
10. The method of claim 1 , wherein the current collector film comprises copper.
11. The method of claim 1 , wherein the pyrolyzed composite film comprises 50% by weight or more of silicon particles.
12. The method of claim 1 , wherein the binder material comprises one or more of: CMC, SBR, Sodium Alginate, polyamide-imide (PAI), polyacrylic acid (PAA), and polyimide (PI).