Method for Producing Composite Powder for Dry Process Electrode for Electrochemical Devices
This novel technology is directed to a low cost and high performance electrode for an energy storage device or an energy storage system and the method for making that device. The types of energy storage devices that can incorporate such electrode include ultracapacitors, lithium ion capacitors, batteries, fuel cells and hybrid cells which are the combination of the above devices. The types of energy storage systems that can incorporate such a low cost and high performance electrode are the energy storage system that uses at least one of the above devices.
This technology comprises a binder composition and a method of making a composite powder for a dry process electrode and a method of producing an electrode. Both of these methods can be used for electro-chemical devices. The binder composition includes bulk polymer, polymer solution, and polymer suspension. The method comprises: 1) making electrode composites including an active material, a carbonaceous conductor and binder wherein the working ranges for each include, by weight, about 70-97% for the active materials, about 0-10% for the conductive material additives, and about 2-20% binder material through solvent-free or solvent assistant process; 2) making uniformly mixed, ready-for-press electrode composite powders comprising of an active material, a carbonaceous conductor and binder using a high speed mixer; 3) form a free-standing continuous electrode film by pressing the uniform mixed powder together through the gap between two roller of a roll-mill, and 4) calendering the electrode film onto a substrate, such as a collector.