Review on Tenergy 7.2V 2000mAh Replacement Battery for iRobot Braava 380 380t 390 390t & Mint 5200 5200B 5200C – Enhanced Power and Durability! by Amber Thompson

The brand new battery when inserted into the Braava 380T robot causes an episode of "My battery is low weak” beeps this will keep bugging you until you unplug the robot from the power source. Of course, without a power supply, the battery will not charge. You can override/reset Braava's beeping by pressing and holding all 3 buttons simultaneously until the beeping stops (about 10 seconds), but after about 5.10 minutes the beeping will resume. You can charge the battery by repeating this process every 5.10 minutes - so not an option in the long run as you have to watch the robot throughout the charging process. Another option is to lock the robot in a place where you won't hear it beeping - the battery will eventually charge. An even better option is to stay away from that junk and buy a battery that actually works.