Industrial light source solutions provider Heraeus Noblelight has confirmed that field testing of its carbon infrared (CIR) technology shows significant quality and production improvement for drying electrode slurry, an important processing step during the production of lithium-ion batteries (LiBs) such as those being used in electric vehicles (EVs). Field trials at customer facilities showed electrode slurry drying is up to 80% faster with CIR emitters compared to convection oven drying. Additionally, both electrode conductivity and durability improved, significantly enhancing battery quality.
The battery electrode manufacturing process is complex with multiple stages affecting the electrode characteristics and final LiB performance. These electrodes are metal foils, mostly made of copper or aluminum, coated with a paste called slurry. Typically, a convection oven dries the electrode slurry at line speeds of 50 m/min. Tests showed that adding Heraeus Noblelight’s CIR emitters enabled line speeds to increase to 90 m/min, 80% faster than current production rates.
Drying electrode slurry with CIR emitters resulted in better crosslinking and less residual moisture improving electrode conductivity and durability. The subsequent electrode baking and calendaring process can also benefit from CIR emitters by eliminating creasing and foil deformation. These higher quality electrodes mean the batteries should last longer.
As the pace of LiB manufacturing increases in North America, with many recent announcements for building production in the U.S., battery producers have the opportunity to choose faster production rates or smaller footprint ovens.
Tom Marrero, Heraeus Noblelight’s manager, battery solutions explained, “With so many new battery production plants being announced for North America, battery producers should consider their options. If production rates are the priority, then they can choose to run 80% faster using CIR emitters. However, if the priority is facility cost reduction, then the battery producer can use the CIR emitters to reduce the oven size and resulting floor space and run production at current rates.”
LiB oven manufacturers and those who integrate entire LiB production lines for battery original equipment manufacturers can now differentiate their solution by offering their customers several options. For example, in addition to the typical convection oven for electrode slurry drying, now they can offer an oven with CIR emitters, or an option for a CIR booster oven prior to the convection oven.