FirstAlert smoke detector low battery warning continues after opening battery drawer and replacing batteries

Question

Note: I'm creating and immediately answering my own question because I wasn't able to find documentation of this solution online.

My condo is equipped with a FirstAlert 7010BSL smoke detector (technically mine is a 7010BSLA model; it appears identical to the 7010BSL). This model of smoke detector is hardwired (i.e., it uses mains/grid power) but also takes batteries to provide power during an outage.

My detector recently started beeping periodically to indicate that its batteries were low. I took out the old batteries and put new ones in, but the beeping continued. This is apparently a common problem with FirstAlert smoke detectors as the company has a dedicated help page for it.

Following the instructions on that page, I performed the following steps:

1. Turned off the breaker connected to the smoke detector
2. Disconnected it
3. Removed the batteries
4. Held the test button for 30 seconds
5. Inserted new batteries
6. Waited a few minutes
7. Reconnected the detector
8. Turned the breaker back on.

After this process, the detector continued emitting the low battery warning.

What might be the solution to this problem?

Answer 1

The problem was that, when I initially removed the old batteries, I damaged one of the terminals within the battery drawer. All the terminals are thin metal plates that deform easily; there are no spring terminals.

When I repeated the steps described above but bent the terminal back into shape before inserting new batteries (between steps 4 and 5), the detector stopped emitting the low battery warning.

For reference, here's a photo of the damaged terminal:

I damaged the terminal because the batteries fit very snugly within the battery drawer and I wasn't aware that they're supposed to be removed by pushing on plastic tabs on the back of the drawer. After being unable to remove them by hand I pried them out with a screwdriver, which damaged the terminal.

Use of the tabs to remove the batteries is described in the manual (excerpt below), but I didn't have a copy of it until I found it online later.

Hopefully this helps other people who also encounter this problem!