Those dividers are to give strength and protection so the pins do not get bent.
You can continue to use it but more than likely the pins are likely to bend on you when you least expect it and cause you problems.
So I would
use in Emergency Flight Only and Mark it so you dont get it mixed up with the other Batteries as that will be very Frustrating.
Phantiomrain.org
Gear to fly in the Rain. Land on the Water and Protect you Batteries.