A few months ago, my brother replaced the sealed lead-acid-battery
in his IBM brand UPS. The UPS worked for a month or so and then it
quit working. The battery supplied outlets were dead and an LED on
the front panel with a sine wave graphic was blinking.

We opened it up and we could not slide the battery out. I had to
cut the case of the UPS up, with tin snips, to get it out. The case
of the battery has a substantial amount of distortion with bulges
and indentations.

Last Saturday, I went to the TRW swap meet and talked to the vendor
who sold my brother the battery. She said that he must have
connected the battery in reverse. I told her that it had worked for
a while and she said that it would work with a reversed battery
until the charging circuit tries to charge the battery.

I am 99% sure that this is BS. What do you think? Thank you in
advance for all replies.
--
Never ever let your brain explode. It's VERY bad for you and
it leaves a terrible mess for someone to clean up.