[X4U] MacBook Battery issue

[Richard Gilmore]

A friend of mine bought a display model black Macbook from a computer store
and because it was sitting out for a year continually plugged in the battery
was shot. So he bought a brand new battery from the same store and
everything worked fine for awhile now a scant 6 months later and after only
40 charge cycles this battery is shot too and won¹t hold any charge
whatsoever and needs to be plugged in to work. He put another battery in
from a friend's Macbook and it worked. He will try getting a new battery
from the store but in the meantime...

Would there be a problem with Macbook not charging properly or did he just
get a dud battery?

Are there any battery utilities people recommend? Coconut battery
continually crashes on his machine and won't give any useful information.
Any other suggestions?

Thank you

Richard