I was surprised when that proved to be true. A day later, the charger showed the battery fully charged and ready to go. It kept working through the four day camping trip without trouble.
Unfortunately, circumstances left the camper idle for another year.
Now I have use for the camper again, the battery is showing zero volts again and I'm not sure of I should try to revive it again. It's not a convenient time to have a lithium battery fire.
The manufacturer of this battery is no longer in business. I cannot call them for technical assistance. Does the abuse of idleness render this battery unsafe? My research is inconclusive.