In my old boyscout days we used steel wool and a 6 volt lantern battery
with some of the most flamable papers and grasses etc to attempt to start a
fire. It took forever and many never got them to ignite. I agree that what
happened to you was not a fire hazard. You'd have a better chance to win the
lottery than to have that ignite on it's own, or maybe getting struck by
lightning, twice.

Wayne

The worst case is if the battery box happens to get hot enough to
melt low-temperature plastic trim, which can be expensive and costly
to replace.

The fabrics used in the interior of the aircraft had durned well better
withstand a much higher temperature without igniting, or someone
installed the wrong stuff. Likewise, it should not get hot enough to
ignite paper.