Replacing batteries inside an Symmetra Battery Unit

The battery packs on an APC symmetra have a life span of around 5
years, and replacing all of them at once is an expensive proposition.
In an attempt to cut costs, I decided to replace the individual
batteries that make up each unit.
APCs SYBT4 part number refers to a 4 pack of the individual SYBTU1-PLP
part, which is a long chassis with a handle at one end and a connector
at the other. Each SYBTU1 contains eight individual batteries, and a
small circuit board.

The batteries found in my particular unit were Vision CP1270s, 12V and
7.0 AH rated. You can get these batteries from online vendors such as
osi battery. They are available with the F1 or F2 designator that
indicates the size of the terminal on the battery – for the APC
project, we wanted the f2 batteries with the 1/4 inch lug.

So, once you have gotten your eight batteries, you can get started.

Pop the case by removing 8 screws, and slide back the cover.

You can see the 8 batteries are wired in series.

Pull each white connector off. Remove the black and red wires from the end batteries. Do not short the batteries!!! I have installed some blue plastic tabs to prevent accidents.

Remove that batteries one by one.  Once you get one out each set of four, they come out easy.

Install the new batteries and rewire, reversing the process of
removing the connecting wires.

Reinstall the cover making sure the tabs line up, and then sliding it in. The 8 crews should go in easy when the cover is properly in position.

Finally, you should label the battery unit with the replacement date.