Electrode for energy storage devices and method of making same
The present invention is directed to an electrode for energy storage devices and a method for making the electrode for energy storage devices is disclosed, where a flexible binder in the electrode formulation is activated by certain additives and is uniformly deposited on to the active and conductive particles by high speed mixing. The particles deposited with activated binder particles are then pressed together to form free standing electrode film. High performance and cost effective products, such as free standing electrode films, laminated electrodes, ultracapacitors, lithium ion capacitors, batteries, fuel cells and hybrid cells which are the combination of the above devices, and the energy storage system or the system blocks, such as modules, can be manufactured using this process.
1. A method for making an electrode for an energy storage device without extrusion, the method comprising:
forming a powder mixture by mixing powder materials comprising active material particles in a working range of about 70-97 weight percent, conductive material particles in a working range of about 0-10 weight percent, and binder material in a working range of about 4-8 weight percent;
activating the binder material by:
(i) adding and mixing solvent to the powder mixture, including a working solids range of about 83-96 weight percent; and
(ii) mixing by high speed mixer all of the mixed materials from (i);
forming a film without extruding the mixed materials by pressing the mixed materials into a free standing film without performing a drying operation on the mixed materials before a next operation; and
laminating the free standing film on to a non-treated current collector to form the electrode.
2. The method for making an electrode for an energy storage device according to claim 1 , wherein said mixing all of the powder materials together includes mixing said active material particles in a working range of about 88-96 weight percent.
3. The method for making an electrode for an energy storage device according to claim 1 , wherein said mixing all of the powder materials together includes mixing said conductive material particles in a working range of about 0-2 weight percent.
4. The method for making an electrode for an energy storage device according to claim 1 , wherein said mixing all of the powder materials together includes mixing said binder material in a working range of about 4-6 weight percent.
5. The method for making an electrode for an energy storage device according to claim 1 , wherein said laminating the free standing film includes laminating the free standing film on to a previously treated current collector to form the electrode.
6. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in an ultracapacitor.
7. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in a lithium-ion capacitor.
8. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in a battery.
9. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in a fuel cell.
10. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in a hybrid cell.
11. The method for making an electrode for an energy storage device according to claim 1 , wherein said electrode is used in an energy storage system comprising system blocks and modules,
wherein at least one of said energy storage system blocks and modules includes said electrode.