If the "lightning bolt" appears, the Moto 360 is good. Wait a while after it begins charging, then touch the screen while it is on the charger. A light ring around the border should appear with a percentage of the charge. As the percentage increases, the ring will be growing, until it reaches 100% and shows a complete ring.
If the ring or the percentage doesn't appear or never increases, then the battery isn't hlding the charge.