"the shop said it was probably the connector on the back of the computer
He took it back to the shop and tried their universal charger and several others that they had and none of them worked."
Any job work carried out should be guaranteed or at least work for a reasonable time.
Get the shop to do the job properly, he paid for it and it will still not charge, tell them to fix it or refund the money, else you will be seeking solicitors advice.
Laptop Battery not showing Charging
1. Turn off the computer,
2. Take the battery out
3. Take out the power supply
4. Push the power button down for 30 seconds.
5. Reconnect power supply
6. Then the battery.
Should now show 100% charged. This is because sometimes the mother board gets static and this clears it and the reason it showed not charging was because it was fully charged.
Could also be a defective battery.