Hello, for my thesis I'm designing a batterypack for a diesel generator as ESS (energy storage system). I'm wondering if stack pressure is needed in a batterypack made of pouch cells. This is not clear for me. This is what I found on the internet:

1) Battery University ( https://batteryuniversity.com/learn/article/types_of_battery_cells):

"The pouch cell offers a simple, flexible and lightweight solution to battery design. Some stack pressure is recommended but allowance for swelling must be made. The pouch cells can deliver high load currents but it performs best under light loading conditions and with moderate charging. Although easily stackable, provision must be made for swelling. While smaller pouch packs can grow 8–10 percent over 500 cycles, large cells may expand to that size in 5,000 cycles. "

2) Battery University (https://batteryuniversity.com/learn/article/what_causes_lithium_ion_to_die#:~:text=During%20charge%2C%20lithium%20gravitates%20to,not%20reset%20the%20battery%20fully.&text=Dahn%20stresses%20that%20a%20voltage,be%20more%20harmful%20than%20cycling.)

The four suspected renegades that are responsible for capacity loss and the eventual end-of-life of the Li-ion battery are:

How can we apply stack pressure and make allowance for swelling at the same time? I'm asking this because my current design looks like the image in the attachment. There is no stack pressure in my model.

Thank you.