5268ac internal battery light blinking

I just purchased and installed a Pace internal battery for my 5268ac gateway.  (Disappointed that it did not come with one.)  When first installing it, the 'battery' light on the gateway stayed on continuously.  Now, after several hours, the battery light is blinking rapidly.  Does that signal trouble with the new internal battery or is a rapid blinking the 'normal' status of a fully-charged battery?