Review on EGO Power Lithium Ion Standard Equipment by William Rothstein

I bought this battery last year and it has died in almost exactly a year. My charger is flashing red, indicating the battery is low. I used it literally from April to September last year and now after sitting in my closet (not attached to the trimmer) over the winter it won't charge. Rip off. I'll have to see if there's a guarantee, but I doubt there's anything I can do in a year. I won't buy any other. Why do my Dewalt batteries seem reliable and long lasting but some of these other companies can't make anything that will last for a reasonable amount of time.