Many people owning APC UPS, eventually they will seek for battery replacement.
RBC6 by APC Anatomy I did take apart today my SMC1500I, mostly for cleaning (internal dust removal) and battery inspection.
By inspecting the battery pack, there was a large air bubble under the APC label, and this helped me or motivated me, for label removal.
All the secrets they are appear at the pictures bellow.
What makes me wonder, this is the selection of the protection fuse, 80A ? This seems as extreme choice of APC, to me.