Good product but bad battery

I love how my vacuum looks like. I can use it in almost any space of my house, it absorbs any kind of dust and is easy to clean, but I got very disappointed in just one fact, it doesn't retain the battery, it doesn't matter how long I let it charge, the most I can use it is 5 minutes, then it turns off by itself. I am not sure if is a problem with battery or that's the real time that is supposed to work.