HP 20 MODULAR SMART ARRAY User Manual page 32

Replacing Enclosure Components
3. Slide the battery unit toward the rear of the controller module and lift it out.
4. On the back of the battery unit, push the two plastic retainer tabs upward through
the slots in the battery case (1).
5. Tilt the battery pack slightly away from the battery case (2).
6. Press down on the battery pack to expel it from the battery case (3).
To install the replacement upper battery pack, reverse the previous steps.
HP StorageWorks Modular Smart Array 20 User Guide 5-5