In order to reduce costs in the cell manufacturing process the electrodes are coated in widths far greater than any battery cell would use. Hence, after coating, drying and calendering it is necessary to cut the electrodes length wise into a usable width.
It is really important that the resultant edges are cut cleanly, without damaging the electrode edge or surface and without leaving debris behind.
Slitter Burrs, Waviness and Delamination
Burrs and wavy edges on cell electrodes can have serious consequences up to and including an internal short-circuit and thermal runaway. Hence it is important to understand the slitting process and under what conditions burrs and waviness occurs.
Image: birds eye inspection of a cut electrode edge
There are two basic slitting options:
- Gang Type
- Goebel Type
- upper flat knife reduces face deflection and reduces burrs
- initial reproducibility is poor
- upper knife position setting by spring results in degradation of quality during operation
- unstable cutting quality
- elastic upper knife
- wide gap between lower knife and spacer
Hence we see that traditionally a lot of manual setup and maintenance is required to achieve the highest quality in the slitting of electrodes.
Maysun Corporation was established based on a Paper-making company in 1967. So we see from perspective of Paper-making manufacturers and have developed technology which they require truly. We are pioneers in the introduction of numerical control to Paper-making machine, and rated highly by our customers.
And other than paper-making, orders of NC Slitters and Non-contact thickness gauges for optical films for Flat Panel Display and electrode materials of lithium-ion battery are increasing in number. Our products rated highly by trendsetter material manufacturers.
Contact Hiroshi Yamada (h.yamada@maytech-corp.jp) for more information (LinkedIn)