What's the over/under?
The write up sounds like they are focusing on a big (UPS) batter to charge smaller batteries. That's fine for those who don't want what a good UPS can provide. As Nate Amsden points out, a good UPS cleans the power it outputs. The other thing a good UPS does is regulates the power it outputs to eliminate high and low (brownouts) voltages. To do this, input power needs to go into the battery while output power is taken from the battery.