Ah or Amp-hours for a lead acid battery are calculated at a current that discharges a battery in around 20 hours, so a 7Ah battery would have to discharge at 7/20th of an amp or 350mA to get an accurate Ah figure. It can drop to 4Ah if drawn down at 4A, due to losses in the battery as heat. In any case your test is near enough and shows the battery is on its last legs. For safety's sake I'd suggest a top brand replacement, Panasonic was always a good brand.
Bookmarks