Robot Reviews

Roomba 531 quite sick

Very " new here" Not sure if im in the right spot but I will learn, so no barking or biting please. I have a Roomba 531. The problem started with a red charging error error 5. I checked the charger voltage at it was putting out 21.6 v at plug end going into the machine. Took the battery out and it read 6.2. This Is a replaced battery from meltasta 6400mah.the battery had the smelt burn to it.