I had the same issue one time with a brand new agm battery which one of the cells was bad. I got a replacement autocraft lithium battery and have been please with it. It has a longer warranty compared to the other two types of batteries (agm/ lead acid) that are advance auto brand. I have had people recommend trickle chargers, but I don’t feel you really need one with a lithium battery unless you are storing it in the cold for a long period of time.