When these fail we use the AC power so it's not a total loss.
Your post doesn't tell any history. Since batteries are a short affair of about 300 cycles or "folk can use that up in a year" you may want to ask how much they used it on battery power.
Netbook reports 0% battery life and will not charge. Have checked all connections. Have not yet switched in alternative battery supply, unavailable. Is it a goner?