Electrode coatings in batteries facilitate the electrochemical reactions that are necessary to deliver electrical energy. The binders used in these coatings are typically only a small percentage of the overall weight of a battery, but they are essential to battery cell construction and delivering a range of benefits, from safety enhancements and energy density to capacity and more.
- a metal oxide-based positive electrode (cathode) that is coated onto an aluminum current collector
- a negative electrode (anode) made from carbon/graphite coated onto a copper current collector
- a polyolefin membrane separator that is also sometimes coated
- electrolytes made of lithium salt in organic solvents
- Aids in film formation
- Helps form a good particle dispersion in solvent or water. The binder must help the coating disperse to deliver a uniform slurry and discrete particles in the cathode and anode
- Remain stable inside the harsh environment of a battery, where multiple reactions happen. The binder can’t break apart or be destroyed in this difficult environment.
When choosing a binder, there are several factors to consider. As mentioned, a binder must perform a number of tasks and do them well—disperse, adhere, bind particles, survive in a harsh environment… plus, it must facilitate the performance of the battery as it is charged and discharged. A battery can slowly lose capacity over cycling and charging/discharging hundreds or thousands of times. A binder plays an important role in maintaining capacity. With a cell phone, a reduction of battery capacity over time could be a nuisance, but with an electric car, it’s more than a nuisance. The binder can influence the capacity and stability of a battery, and ultimately battery life.
Smaller, Lighter, More Powerful
As battery manufacturers continue to develop more powerful, more stable and smaller/lighter batteries, Lubrizol is committed to assist. Through our expertise and capabilities, we're focused on enabling enhancements to battery life and the ultimate cost of the battery through advancements in binders/dispersants for anodes, cathodes and separators. This is evident in mobile phones and laptop computers as they continue to get thinner and lighter thanks to battery technology. They are also evident in electric vehicles, where battery weight and size are shrinking while the drivable range on a single charge continues increasing.
Contact us to collaborate on meeting the needs of the next generation of batteries using the form below, or visit Electro-Rite® Technologies for Batteries to learn more.