I’m the proud owner of several Blue Robotics batteries, due to the pandemic they have all been in storage with the rest of the ROV gear for about 10 months. I’ve always made sure to follow the product guidelines on long term storage with regard to voltage and temperature.
I am currently charging some batteries to head our to the field, using the now retired Blue Robotics charger. When charging is complete I decided to put it on monitor mode for a little while just to see, I did notice about a 1 volt drop from max charge voltage of 16.8 over a period of about a minute with the voltage still dropping a little bit at a time.
Should I be concerned about this? Is the internal resistance of the charger enough to drop the battery voltage that much immediately after charging? What signs should I be looking for before going through the effort of operating my ROV that my batteries are in good health?